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Qatar Foundation Annual Research Conference Proceedings Volume 2018 Issue 1
- Conference date: 19-20 Mar 2018
- Location: Qatar National Convention Center (QNCC), Doha, Qatar
- Volume number: 2018
- Published: 12 March 2018
51 - 100 of 142 results
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Heterojunction Solar Cells Exceeding 20% Efficiency Using Gettered Monolike Silicon Wafers
Silicon heterojunction (SHJ) solar modules are an attractive and suitable option for application in high temperature environment such as in the state of Qatar. This is mainly related to their high open-circuit voltage (Voc) [1], which is essential for achieving better performance at high temperatures. High efficiency SHJ solar cells are usually made from high-quality n-type monocrystalline silicon wafers, which increases the cost of the device. If lower-cost materials such as high performance multicrystalline and mono-like silicon wafers could be used, significant reduction in the cost of PV electricity can be achieved. In this work, electrical properties of industrial-scale n-type and p-type mono-like silicon wafers have been investigated for use in high efficiency SHJ solar cells. The wafer's electrical resistivity were measured by four-point probe as 1–3 Ω-cm for n-type and ∼1 Ω-cm for p-type wafers. Since minority carrier lifetimes in as-grown (un-gettered) cast silicon, including mono-like silicon is usually low (i.e. inadequate for application in high efficiency solar cells), phosphorus diffusion gettering in a POCl3 furnace and/or bulk passivation by SiNx:H were used for enhancement of electrical properties. SHJ solar cells were then fabricated using the gettered wafers and as-grown sister wafers to assess the effectiveness of the gettering treatments. Figure 1. Injection dependent minority carrier lifetime for as-grown wafers and for gettered sister-wafers, after passivation with i/n and i/p amorphous silicon layers Figures. 1 shows minority carrier lifetimes measured by Quasi Stead-State Photoconductivity (QSSPC), on wafers as-grown, gettered and gettered with SiNx:H bulk passivation. As-grown lifetimes are low, being < 170 μs for p-type wafers and < 370 μs for n-type wafers, at 1 × 1015 cm-3 injection level. After passivation, significant improvement (up to 520 μs for p-type and 1900 μs for n-type) was achieved at 1 × 1015 cm-3 injection level. Despite the significant enhancement in overall lifetime, lifetimes at low-injection level is still limited, particularly for the p-type silicon. Nevertheless, very high carrier lifetime (up to 2400 μs) was recorded at 1 × 1015 cm-3 injection level (Figure 1(a)), and a SHJ cell with VOC of 720 mV and a photo-conversion efficiency of 20.3 % were successfully achieved, by gettering and bulk passivation. In conclusion, we demonstrated that electrical properties of industrial-scale mono-like silicon wafers can be efficiently optimized by gettering and bulk passivation treatments for application in high efficiency solar cells. A silicon heterojunction solar cell with efficiency exceeding 20% was produced. References [1] S. De Wolf, A. Descoeudres, Z. C. Holman, and C. Ballif, «High-efficiency silicon heterojunction solar cells: A review,» Green, vol. 2, pp. 7–24, 2012.
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A Noval Self Healing Control System for Next Generation Electric Grid with Big Data Platform
Authors: Shady Khalil, Mostafa Shahin, amira Mohamed and Haitham Abu-RubNowadays, many electrical utilities are moving towards self-healing distribution grid. This is realized by adding to distribution system various sensors, intelligent electronic devices (IEDs), phasor measurement units (PMU), sequence of event recorders (SERs), reclosers, detectors, measurement units, automated controllers, and other automation equipment. Those elements provide a continuous stream of data to support grid performance and improve its reliability. Huge amount of data obtained from different smart grid sources satisfy all the Big Data (BD) characteristics. The success of future electric grid depends mainly on the effective utilization of the huge amount of the data flow. This mass of information is essential to make next generation electric grid more efficient, reliable, secure, independent, and supportive during normal conditions and contingencies. The self-healing grid requires a robust real-time computation system that monitors, processes, provides predictive analytics, performs data mining and statistics, and makes faster decisions of the diverse and complex data collected within the traditional and nextgeneration electric grid. This helps to detect, locate, and isolate various faults, reconfigure and reroute power of the distribution network to minimize service disruptions and outages.Implementation of self-healing control system is associated with big data utilization which is a persisting challenge. Computational complexity challenges is associated with processing huge amounts of data during operation of the electric power system. Therefore, this paper presents acomprehensive studies of the impact of implementing a smart real-time dynamic self-healing control strategy using BD process platform with deep learning technique on the distribution system for current grid and future smart grid. The deep learning technique is a subfield of machine learning. The deep learning is shown to be highly efficient solution for the analysis of massive amounts of data which is performed by discovering and utilizing available regularities in the inputs to help self-healing control system to network reconfiguration, and coordination of various distributed energy resourcesin the smart grid. The deep learning system complexity does notdepend on the number of grid buses, this is because the power flow solving time is approximately linear with respect to the number of system buses. However, the complexity of the system depends on the number of the system inputs. The Long Short Term Memory (LSTM) recurrent neural network will be used in modeling sequential data such as time series data. Such network has the ability to learn contextual information over the history of the input sequence. The BD analyticswill be used as a key to deal with the uncertainties and different sizes of structured and unstructured data. The advanced analytics techniques such as predictive analytics, in addition to data mining, statistics, and faster decisions making will be utilized for data coming from sensors within the traditional and next-generation electric grid. The studies performed are based on real-time monitoring and control of the network topology and operating conditions taking into account different power sources and hybrid renewable energy sources which usually have different characteristics on the electric power grid. Finally, the real-time implementations of the proposed system will achieve dynamic resources optimization, network reconfiguration, and optimum operation of power grid using LSTM with big data platform.
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Synthesis and Properties of Novel NiBAlN Nanocomposite Coatings
Degradation of materails due to corrosion has now emerged as an international challenge which is compelling the community to trace out some smart solutions on priority basis. Corrosion mitigation is not only important as it results in wastage of our natural resources, time, money and efforts, but more importantly its inadequate handling may lead to the safety threats. Some, such sad incidents have been reported in the past. That is why many countries of the world are paying special attention to address this challenge by investing a lot of money. Although, we can notice corrosion everywhere around us, however, mining, mineral processing, oil & gas and many other processing industries are facing severe corrosion challenges. In many applications, it is only the surface of the material that is directly exposed to the corrosive medium, hence modifying the surface properties may lead to control the corrosion phenomenon. Towards this goal, the development of various types of nanocomposite coatings has proven to be a an economic and viable option. The present research work addresses the synthesis and characterization of novel Ni-B-AlN nanocomposite coatings. The Ni-B and Ni-B-AlN nanocomposite coatings were electrodeposited on the mild substrate. A comparison of structural, surface, mechanical and electrochemical properties are presented to elucidate the beneficial role of the incorporation of AlN nanoparticles into the Ni-B matrix. We have noticed that the addition of AlN nanoparticles to Ni-B matrix has a remarkable effect on its properties. Ni-B-AlN nanocomposite coatings demonstrate superior structural, mechanical and anticorrosion properties when compared to Ni-B coatings which make them attractive for many industrial applications.
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GridConnected CapacitorTapped MultiModule Voltage Source Converter
Authors: Ahmed Abbas Elserougi, Shehab Ahmed and Ahmed MassoudIn this work, a new dc-ac converter is proposed for grid integration purposes, namely, capacitor-tapped multi-module dc-ac voltage source converter. The main advantages of the proposed converter when compared with the conventional dc-ac modular multilevel converter (assuming the same voltage rating of semiconductor devices) are: (i) employment of a lower number of semiconductor devices, but with a higher current rating hence it provides operation with a lower number of gate driver circuits, and (ii) employment of a lower number of dc capacitors which reduces the number of measured variables, which affects positively the cost and reduces the computational burden of the employed controller.
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Solar Thermal System for Heating and Cooling Requirements of Commercial Building in Doha: A Case Study
Authors: shoukat alim Khan, Majid Aziz and Muammer KocThe demand for cooling in Gulf region is the direct effect of its high atmospheric temperature. Around 60% of the electricity demand in GCC is for cooling purpose. The main source of cooling and air-conditioning in these countries are conventional electric compression cycle, which leads to the increase in the GHG emission, directly in the form of leaked gases from these systems and indirectly in the form of fossil fuel used for the production of the used electricity for these systems. Solar energy in general and solar thermal energy specifically can be a promising and sustainable solution to the cooling and air-conditioning requirement for the buildings in Qatar and GCC. Absorption cooling and air-conditioning is a mature and promising technology with respect to its efficiency and results on the industrial scale. However, the use of technology with solar thermal energy is new in the market. In this paper, the feasibility analysis of solar thermal technology has been done for the cooling, heating and hot water requirement of a commercial building in Doha, Qatar. Heating and hot water requirement for winter and cooling requirement for summer season were calculated and used as a load. Solar thermal collectors (STC) were used as the main source of thermal energy collection form sunlight. Along with STC, thermally driven adsorption chiller was designed to fulfill the cooling requirement in the summer season. The design and selection of the different components and parameters such as Solar thermal collector area, storage tank size, adsorption chiller etc. have been done in detail. The result, obtained for building's energy demand and its supply from the designed solar thermal system, gives a clear sign for the successful implementation of this technology.
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Counting the Carbon: Assessing Qatar's Carbon Dioxide Emissions
Authors: Mona Al-Asmakh and Nadya Al-AwainatiClimate change is the most pressing global environmental issue today, with a potentially devastating impact on human development. According to the Intergovernmental Panel on Climate Change (IPCC) reports, Qatar is ranked as the highest CO2 per capita emitter globally. Qatar is contributing to the reductions of anthropogenic carbon dioxide (CO2) by supplying the world with Liquid Natural Gas (LNG), yet Qatar is being negatively imaged as highest CO2 per capita emitter. The reading of the highest CO2per capita has affected Qatar's ability to attract green investments and to improve the country's attraction in the tourism market. Qatar's position as the leader CO2 per capita has made it unattractive for investors both internally and externally because of the perception that the investment would not be ‘green’. The per capita emissions are a result of two main factors: the total absolute emissions and the total population. Two major and significant factors, consumption and population, should be taken into consideration when discussing the total absolute emissions for Qatar: The assumption for this equation is that the population uses all the produced energy, which is the denominator. This assumption is a disadvantage to Qatar due both to its low population and the fact that it is an energy producer. CO2emission would be much lower for Qatar if a consumption-based accounting system was used for the calculation of the per capita value. The use of emissions accounting measure is of vital importance to individual countries. There are two feasible carbon emissions accounting units: production-based accounting and consumption-based accounting systems. Production-based accounting is linked to economic system boundaries (greenhouse gas emissions from resident institutional units, analogous to gross domestic product). It involves measuring the emissions occurring within a country's boarder and does not take into account production chains extended across boundaries. An illustration of a production-based system examines the emissions generated from fuel purchases and allocates them the country producing the fuel, not the country consuming the fuel (OECD, 2016). While the Consumption based accounting system is related to how much this country emit for its domestic uses. Data are more difficult to obtain for the consumption-based approach because the computations are more complicated to compile as it relies on input-output tables, which includes all steps in production from raw material extraction through the final assembly and ultimately the final sale of the product (General Secretariat for Development Planning, 2009).The controversy comes in determining responsibility: is it the player initiating the polluting process (consumer) or the player producing the pollution (producer)? Consumption-based measures are preferred by developing countries while production-based measures are preferred by developed countries. Qatar is unfairly portrayed as the highest carbon dioxide emitter in the world in terms of per capita measures. Qatar's carbon footprint takes into account Qatar's energy production rather than the country's domestic consumption. The main argument of the paper is to discuss Qatar's CO2 emissions per capita compared to other reporting measures, and to examine the difference between using a consumption based CO2 emissions accounting system versus a production-based one for Qatar. The paper discusses the complications of using a production-based accounting versus a consumption-based accounting system for Qatar carbon dioxide emissions calculations. The research applies both of Quantitative and Qualitative Analysis. The Quantitative analysis is related to roughly re-estimate Qatar's CO2 Per Capita emissions figure based on Consumption based accounting system. The qualitative analysis focuses on creating different comparisons to compare Qatar's CO2 emissions in terms of different reporting measures to three different categories. First category is comparing Qatar's emissions against GCC countries; these countries have the major common attribute that they are mainly dependent on oil and gas revenues, similar demographic location, weather and lifestyle. The analysis outcomes of this category illustrates that KSA has the highest emissions for CO2 intensity and for the absolute emissions. The second comparison category is comparing Qatar's CO2 emissions against major Liquified Natural Gas (LNG) producers which are Australia and Malaysia. These comparisons showed that Australia has the highest emissions of Absolute CO2, CO2 intensity as well as the emissions per GDP. The third category was to compare Qatar's position related to the major global emitters, such as China, India, Russia, and USA. This comparison resulted in China having the highest absolute emissions, CO2Intensity as well as emissions per GDP. The Analysis outcome of the comparisons highlights that Qatar is not the highest CO2emitter in terms of absolute CO2 emissions, emissions intensity, and emissions per GDP compared to the GCC countries, major LNG producers and the world largest emitters. Qatar has the highest CO2 emissions per Capita due to two main factors: Qatar is the largest LNG producer and Qatar has a relatively small population when compared to other countries. Qatar is a developing country, it is the largest LNG exporter and it has third highest natural gas reserves in the world. Qatar makes an indirect contribution to mitigating the impact of climate change, which is done though exporting a clean form of energy, i.e., Liquefied Natural Gas. Even though Qatar is a major contributor for the supplying the world with clean energy, Qatar has taken other initiatives to minimize its carbon emissions. Continuous research and development will be a key element to Qatar overcoming the climate change challenges through Research and Development Centres. In summary, the research paper has four main sections. The first section of the paper includes a background on climate change, its impact and mitigations. The second section discusses Qatar's global position using different CO2 emission reporting measures, including Absolute CO2emissions (kt), CO2emissions per GDP (kg per PPP$ of GDP), CO2intensity (kg per kg of oil equivalent energy use), CO2emissions per capita (metric tons per capita). The third part explores Qatar's CO2 per capita calculation incorporating the consumption-based accounting system and assessing the complications of using a production-based accounting versus a consumption-based accounting system for Qatar carbon dioxide emissions calculations. The last section covers Qatar's clean initiatives and offers recommendation towards net zero emissions and improving Qatar sustainability figures.
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Production of hazardous gas sensors using spinel ferrite nanoparticles
Authors: Jocelyn Ayesh and Mohammad Abu HaijaThis work reports on sensitive and selective gas sensors based on copper ferrite (CuFe2O4) nanoparticles. The nanoparticles were produced different methods including: colloid microwave assisted hydrothermal method, and co-precipitation method. Those methods enable a precise control of nanoparticle size, The produced nanoparticles were annealed at different temperatures. Structural analysis were carried out using x-ray diffraction (XRD) and transmission electron microscopy (TEM), and they revealed that the asprepared nanoparticle exhibit cubic structure. The nanoparticles undergo crystal structure transformation to tetragonal structure upon annealing. Furthermore, the nanoparticle were found to grow in size upon annealing. The tetrahedral and octahedral absorption bands which are characteristic of the spinel ferrite were determined using Fourier Transform Infra-Red Spectroscopy (FTIR) measurements. Gas sensors were fabricate by pressing the produced nanoparticle powder into disks. The sensor device was produced utilizing capacitor structure, with the top electrode stainless steel of grid structure. The produced sensors were characterized to be sensitive to both H2S and H2 gases, with greater sensitivity to H2S at low temperatures, where these sensors could detect H2S concentrations of 10 ppm at 80°C. The low optimal operation temperature reveals the low power requirements for sensor operation. Thus, those sensors exhibit the potential to be used for industrial applications, especially for the petrochemical industry the Petroleum Institute under a grant number RIFP-14312 and Qatar University.
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A new ELLAM implementation for modeling solute transport in fractured porous media
Authors: Fanilo Heninkaja Ramasomanana, Marwan Fahs, Husam Baalousha, Nicolas Barth and Said AhziThe fluid flow and solute transport through fractures in rocks are processes that have importance for many areas of the geosciences, ranging from groundwater hydrology to petroleum engineering. It is well known that fractures play an important role in flow and transport processes through geologic formation and number of environmentally relevant problems require the analysis of mass transport in subsurface systems. As Qatar»s aquifer is Karstic, the development of an appropriate numerical model is necessary to take account the high contrast between the fractures and the porous matrix. Fractures are the set of rock discontinuities that can occur in geological formations at different scales. They intensively affect the transport processes because they represent the preferential flow and mass migration paths. In this study, we introduce an adaptation of the Eulerian Lagrangian Localized Adjoint Method (ELLAM) [1] for the simulation of mass transport in fractured porous media. The fractures are represented explicitly using the discrete fracture model (DFM) which handles explicitly the fractures and matrix. It involves describing each fracture individually and discretizing fractures as well as matrix [2]. Specific physical and geometrical properties are imposed for the fractures and matrix domains. This model can be used in the domains where a relatively small number of fractures exist. DFM is the most accurate model because fractures are considered without any simplification. However, this model requires enormous computational time and memory due to the dense meshes resulting from the explicit discretization of the fractures. As a consequence, its use requires highly efficient numerical methods for solving the flow and mass transport. The flow problem is solved using the Mixed Hybrid Finite Element Method (MHFEM) [3] which is well known to be accurate and efficient for complex geometries. It provides consistent and accurate velocity even in highly heterogeneous domain, which is a relevant property for flow in FPM. The obtained velocity field is then used to solve the mass transport problem with ELLAM. ELLAM combines an Eulerian and Lagrangian treatments without any splitting procedure by considering trial functions that depend on time and space. The results obtained by Celia et al. [1] demonstrated the mass conservation of the ELLAM in its formulation and its high computational efficiency compared to classical numerical method. In this work, a new ELLAM implementation is developed to address numerical artifacts (spurious oscillations and numerical dispersion) arising from the high contrast of velocities between fractures and porous matrix. Moreover, the efficiency of the developed ELLAM implementation was improved, taking advantage of the parallel computing on shared memory architecture for the tasks related to particles tracking and linear system resolving. The performance of ELLAM was tested by comparison against the Eulerian discontinuous Galerkin method based on several benchmarks dealing with different fracture configurations. The results highlight the robustness and accuracy of ELLAM, as it allows the use of large time steps, and overcomes the Courant-Friedrichs-Lewy (CFL) restriction. This work contribute to the Aquifer Storage and Recovery (ASR) project of Qatar which aims at artificially storing water in the aquifer for future use by developing an efficient and accurate model for mass transport in fractured porous media. References [1] Celia, M.A., Russell, T.F., Herrera, I., Ewing, R.E.: An Eulerian-Lagrangian localized adjoint method for the advection-diffusion equation. Advances in Water Resources. 13, 187–206 (1990). doi:10.1016/0309-1708(90)90041-2 [2] Karimi-Fard, M., Durlofsky, L.J., Aziz, K.: An Efficient Discrete-Fracture Model Applicable for General-Purpose Reservoir Simulators. SPE Journal. 9, 227–236 (2004). doi:10.2118/88812-PA [3] Younes, A., Ackerer, P., Delay, F.: Mixed finite elements for solving 2-D diffusion-type equations. Reviews of Geophysics. 48, (2010). doi:10.1029/2008RG000277
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Hydrodynamic Modelling of a complex marine system: Application for the Inland Sea Khor AlAdaid Qatar
More LessPhysical Oceanography is the study of the conditions and processes that govern the movement of ocean water, and its interaction with coastal, seafloor, and atmospheric boundaries. Understanding these processes helps to provide deeper insight into various ecological and physical phenomena that affect the earth's near-surface systems. Furthermore, consideration of physical oceanography is critical for sustainable development and effective urban planning, as most human settlements are along coastlines and thus they experience the combined effects of marine weather, waves, tides, and coastal currents. To help understand the response of marine systems to physical forcing, such as changes in temperature, wind, and humidity, computational eco-hydrological models are created. These models seek to mimic the real environment by using both general and site-specific data related to the hydrodynamics and ecological / physical phenomena, which are then combined with mathematical principles to describe a functional ecosystem.
Most modeling software are designed to simulate flow in “normal marine” systems, i.e. relatively deep systems with near-normal seawater salinities. Khor Al-Adaid (including the Inland Sea), Qatar, however, presents a globally unique marine system, as it is aerially extensive, very shallow (mostly less than 5 m), and hyper-saline. It is surrounded by Eocene rock outcrops, sandy sabkhas, and large mobile dunes which migrate into the Inland Sea water. This marine embayment can be divided into three main areas including: (i) an inner lagoon less than 2 m in depth but 53.5 km2 in extent, with salinity reaching 90 ppt in the summer season, (ii) a 74 km2 outer lagoon up to 18 m in depth with typical salinities of 60 ppt in the summer season, and (iii) a linear channel that is about 10 km long, less saline (∼45 ppt), and it is connected to the Arabian Gulf. The varying range in average salinity, depth, and temperature between these three areas, makes the Inland Sea an intricate system, and thus the hydrodynamics of this system cannot be characterized using existing commercial modeling software, which typically handle more homogenous systems.
This work presents a proposed workflow that will be developed through iteration and testing of existing software, which will account for the modeling challenges faced with a complex heterogeneous system like the Inland Sea. As a starting point, GEMSS (Generalized Environmental Modeling System for Surface waters) will be used, as it provides a set of hydrodynamic, sediment transport and water quality modules, and has been used and calibrated previously in various locations around the Qatari coast to date. Comprehensive field data will be collected and processed to help understand the flow dynamics of the system. Measurements will be made using current meters, ADCPs (Acoustic Doppler Current Profiler), tidal gauges as well as temperature and salinity meters deployed throughout the study area. The data will then be used to build and calibrate the model to assess whether the system can be handled as a whole using GEMSS, or if the areas should be subdivided and treated separately.
The findings of this work will act as a stepping stone to help understand current flow dynamics in the system and how these flows shape the salinity profiles and physical structures. In turn, this will offer insight into the important habitat features currently observed in the system, and add better understanding as to how these may be altered naturally and potentially by anthropogenic means.
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Ecogenotoxicological Impact of Marine Pollutants on Qatari Bivalves: An Experimental Approach
Authors: Zenaba Khatir, Radhouane Ben Hamadou, Pedro Range, Hajer Alnaimi and Alexandra LeitãoThe geographical and hydrological characteristics and industrial activities of the Arabian/Persian Gulf contribute to its classification as a stressed marine environment. The persistency of some contaminants released by human activity is putting additional pressure on this already fragile system. Several studies have assessed the chemical contamination levels in Qatari coastal sediments but this is one of a few studies that assessed their eco-genotoxicological impacts, by using cytogenetic endpoints in a local model bivalve species. Bivalves were specifically selected for this study due to their role as filter feeders, high tolerance for harsh environmental conditions, and availability around Qatar. In this project, determination of Polycyclic Aromatic Hydrocarbons (PAHs), Total Petroleum Hydrocarbons (TPHs) and trace metals in surface sediments and pearl oyster -Pinctada radiata- was conducted in samples collected from 3 coastal locations in Qatar: Umm Bab, Dukhan and Al-Wakra. The selected sites were expected to be dissimilar in regard to the chemical pollutant level and contaminants distribution due to the different anthropogenic activities. Initial aneuploidy levels –numerical abnormality in chromosomes- in oysters were examined between December 2015 to February 2016 through randomly selecting 140 well spread metaphases. Metaphases with 26 chromosomes were recorded as diploid or normal and the ones with less or more number of chromosomes considered aneuploidy (Ebied, 1999). The ability of the oysters to adapt in terms of chemical contaminants accumulation and aneuploidy level when moved between sites with different levels of chemical pollution was assessed in the second sampling in April 2016, and using experimental approach with three treatments (control, transplanted, and translocated). The control treatments were collected from the original site and kept there, the transplanted treatments consisted of individuals composed from the other two sites and moved to Al-Wakra and the opposite, while the translocated treatment were the ones moved from Dukhan to Umm Bab and versa vise. Statistical analysis showed significant difference between sediment in the three sites; TPHs concentrated in Umm Bab, higher concentrations of metals found in Dukhan, while PAHs concentrated the most in AL-Wakra. Hydrocarbons and metals were detected in higher doses in oyster tissues collected in first sampling comparing to those analyzed in the second sampling with consistency of accumulating same contaminants. Predation by gastropod whelks caused high mortality of oyster during the second stage of the study especially in Dukhan control while transplanted animals from Al-Wakra were the least selected by gastropods. Mortality rates in Dukhan were generally higher than in other sites, except for oysters transplanted from Al-Wakra to Dukhan. Positive correlation was found between the high levels of contaminants and aneuploidy during the first phase. Unexpectedly, to the usually observed in bivalves, there was a bigger percentage of abnormal cells with chromosomal gain (hyperdiploids) than with chromosomal loss (hypodiploids) in all treatments. Among all the treatments, transplanted oysters showed the lowest level of aneuploidy followed by translocated, then control. In other words: oysters moved from site to another, regardless of the contamination levels at origin and destination, showed some recovery from initial aneuploidy levels. Further research is needed to determine the underlying mechanisms for this pattern.
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Immobilized Nanosize ZrMetal Organic Frameworks ZrMOFs: Highly Active Reusable Catalysts for Cross Coupling Reactions
More LessFunctionalized Zr-based metal-organic frameworks (UiO-66-fun) have emerged as promising class of porous functional materials with very large specific surface area, ultrahigh porosity and chemical tunability as well as high stability in water and humid environments, which results in desirable properties for several catalytic applications.1–3 These high stable materials were selected as supporting molecular MOF catalysts. We have applied a simple and highly efficient method for synthetic post-functionalization of new and readily recoverable molecular catalysts that combines the catalytic active transition-metal complexes with the architecture of nano-size MOF and their application for cross coupling reactions. In the catalytic process, substituted aryl halides and arylboronic acids converted into corresponding biaryls through C-C bond forming process in a milder condition (Chart 1). In the tested catalysis reactions, functionalized nano-size UiO-66-fun catalysts can be recovered by simple filtration/centrifugation in air and reusable without significant loss of catalytic activity and while framework structures are maintained stable. The detailed post-functionalization and catalysis results will be presented. References: Kim, M.; Cahill, J. F.; Fei, H.; Prather, K. A.; Cohen, S. M. J. Am. Chem. Soc. 2012, 134, 18082.Bosch, M.; Yuan, S.; Rutledge, W. Zhou, H.-C. Acc. Chem. Res. 2017, ASAP, DOI: 10.1021/acs.accounts.6b00457. Pascanu, V.; Yao, Q.; Bermejo Gomez, A.; Gustafsson, M.; Yun, Y.; Wan, W.; Samain, L.; Zou, X.; Martin-Matute, B. Chem. - Eur. J. 2013, 19, 17483. Acknowledgment: Support of this research by the NPRP award (NPRP 9-377-1-080) from the Qatar National Research Fund.
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Environmental Assessment of RO Intakes Applicable for Qatar and the GCC Region
Authors: Hamish R Mackey, Abdulrahman Al-Kaabi and Sami G. AlGhamdiThe State of Qatar and the Gulf Cooperation Council (GCC) region are located in a hyper-arid area with no rivers, over-abstracted groundwater supply and limited rainfall. Consequently, with the discovery of oil and gas and the associated economic prosperity, the State of Qatar and the GCC region have relied on desalination of seawater from the Arabian Gulf. As of 2013, the GCC region held a 70% share of total global desalination capacity.Multi-Stage Flash (MSF) desalination technology has been the source of water supply in the State of Qatar and the GCC region for the past few decades due to the low cost of energy in these countries and the problems historically faced by Reverse Osmosis (RO) membrane processes in dealing wih the high salinity of the Arabian Gulf. MSF is a thermal process that distills water through stages based on high temperature and changing pressures. The systems suffer from high energy requirements and low recovery rates resulting in significant discharge of brine with elevated temperature to the ambient receiving water. RO on the other hand relies on applying a positive pressure to pass permeate through a fine polymer filter material against the osmotic pressure gradient. RO is widely adopted worldwide due to its lower energy consumption and increased product recovery. With recent developments the technology can cover the high salinity of the Arabian Gulf (40,000 mg/L to 55,000 mg/L total dissolved solids). Nevertheless, RO systems require extensive pretreatment to ensure the integrity of the membrane and to prevent blocking of the fine pores. This makes the process susceptible to surface water quality fluctuations such as during algal blooms and therefore its application in Qatar is still challenging due to the shallow and enclosed nature of the Arabian Gulf.Subsurface intake processes for RO have the potential to reduce the effects of fluctuations in source water quality and reduce the energy intensity of the process, since they provide natural filtration of the source water and simplify the extensive pretreatment requirements necessary to protect the RO membranes. However, significant tradeoffs occur by using subsurface intakes. For instance, intake pumping may be increased to overcome the additional headloss through the intake media while the construction phase also involves increased civil works. This research investigates the environmental impacts associated with the operation phase of RO systems using both open intake and beach well intake systems theoretically located in the State of Qatar, since operational phase impacts typically comprise most of the environmental loads in cradle-to-grave assessments.The study utilizes Life Cycle Assessment (LCA) methodology to assess a wide range of effects from the systems. The ReCiPe lifecycle impact indicator approach is utilized with mid-point impact indicators including climate change, marine eutrophication, terrestial acidification, photochemical oxidant formation, particulate matter formation, marine ecotoxicity, water depletion, mineral resource depletion and fossil fuel depletion. The RO system, its pretreatment and intake will be sized and modelled for a desalinated water output of 100,000 m3/d using a combination of fundamental process equations and commercially available software. The results will show a clear direction from an environmental perspective on which type of intake system Qatar should consider if implementing seawater RO as a preferred desalination technique.
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Coral bleaching in extreme environments: speciesspecific thermal tolerance limits
Increasing seawater temperatures are being measured worldwide, causing coral bleaching events during which the symbiosis between the coral host and its symbiotic zooxanthellae is disrupted, and a global decline in reef corals. In the Arabian Gulf where water temperatures are naturally extreme with summer maxima at 35°C and above and winter minima at 18°C and below, seawater temperature anomalies are repeatedly recorded in the summer. While Arabian Gulf corals have naturally evolved to survive at temperatures that would cause bleaching and mortality to most corals elsewhere, an increasing number of mortality events have been recorded in the Gulf (Qatar, Saudi Arabia, and the UAE) in the last decades, resulting in a substantial loss of biodiversity and coral cover, mostly in inshore environments. Efforts are being deployed locally to conserve remaining habitats and attempt the restoration of lost habitats, but to be successful, efforts need to incorporate regional species-specific traits such as the susceptibility and resistance to future bleaching. We here assess the tolerance and sensitivity of three ecologically important species from the Arabian Gulf, Acropora downingi, Porites lutea, and Dipsastraea pallida, sampled in Qatari offshore reefs in the mid-winter, by exposing them to heat stress in enclosed aquaria. Colonies were assigned to control aquaria maintained at 25°C, aquaria to be raised to 30°C, or aquaria to be raised to 36°C. After an acclimatization period, the 30°C and the 35°C aquaria were raised to their target temperature at a maximum rate of 1°C per day. During the warming period and for another three weeks, we monitored the photosynthetic activity of their symbiotic zooxanthellae twice a week with a diving-PAM fluorometer while checking for signs of bleaching. We found that the photosynthetic activity was not affected in any of the three species when the temperature was raised from 25°C to 30°C. At 34°C, the photosynthetic activity in A. downingi started declining. Once the temperature reached the 35°C target, all A. downingi colonies bleached, expelling their zooxanthellae, and died three days later. The photosynthetic activity in P. lutea and D. pallida started declining once the temperature reached 35°C and continued declining for an additional three weeks, after which P. lutea died and D. pallida recovered. The high tolerance of P. lutea and especially of D. pallida is promising for the survival of the two reef-builders in coming years, despite increasing seawater temperatures caused by climate change. However, the branching Acropora coral is not expected to respond well to any further increase of temperature, as reflected in its major regional decline in the past decades. Due to its high sensitivity, Acropora might also not be a good candidate in coral restoration projects, as it showed a high sensitivity to bleaching and the inability to survive bleaching events. However, aquarium conditions not being able to fully reflect natural conditions on the reef, further work would need to be conducted directly on the reef to determine whether other factors might be involved in assisting resistance to bleaching, survival under bleaching conditions, or recovery following bleaching. In any case, P. lutea and D. pallida would be excellent candidates in coral restoration projects, having showed a lower sensitivity to bleaching and the ability to survive for several weeks under thermal stress, therefore showing potential for a long-term survival even under warming conditions.
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Developing an ecofriendly approach to reduce the use of biocides for preventing Microbial Induced Corrosion
By Saad RasoolSulfate Reducing Bacteria (SRB) cause significant damage to marine oil pipelines necessitating the use of biocides for reducing the Microbial Induced Corrosion (MIC) and potential for great environmental harm. Currently, oil companies pump frequent batches of biocides to these under water pipelines without proper quantification of the bacterial population. This is primarily because the existing method for quantifying the bacterial population in a sample is not very effecient, as it can take up to 2 weeks to obtain the results. Our team has focused on developing an eco-friendly approach to limit the use of these biocides, which are used for targeting the SRB. SRB require high salt and low oxygen so first we genetically engineered a strain of bacteria that would report the osmolarity in oil pipelines, thus act as a biosensor for salt concentrations. The ratio of salinity in the seawater flowing in versus the seawater flowing out of the well will be used to estimate SRB populations in the pipelines, thus limiting the amount of biocides added in times of high Microbial counts.
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CFD Analysis of Falling Film Wettability in MED Desalination plants
Authors: Furqan Tahir, Abdelnasser Mabrouk and Muammer KocIn Gulf Cooperation Council (GCC) countries, 56% of the market is captured by thermal based desalination (both MED and MSF), while in Qatar 91% is based on thermal desalination. Among the thermal desalination technologies, Multi Effect Desalination (MED) operates at lower specific power consumption and is considered more energy-efficient than the Multistage Flash (MSF) distillation. The lower energy consumption of MED plants is due to high overall heat transfer coefficient and low pumping power. The most common problem in MED evaporators is fouling of tubes, which reduces heat transfer and performance. Horizontal falling film evaporators are the most common evaporator type used in MED; in which liquid film is maintained outside the tube and part of it evaporates producing vapors. Improperly maintained liquid film leads to fouling i.e. formation of salts on the surface of tubes, which affects heat transfer properties of the surface. So in order to minimize fouling, tubes should be completely wet; especially column based on second row in triangular pitch configuration and bottom row tubes, which receive lesser mass flux. Wettability study of falling film evaporator in 3-D domain is carried out using commercial CFD tool i.e. Ansys fluent v18.0. A column of three tubes having OD 19.05 mm, vertical pitch of 24.7 mm and 20 mm section is considered in this study. Brine inlet has an opening of 1 mm × 1 mm and mass flux (Wetting rate Γ) is varied from 0.03 kg/m-s to 0.2 kg/m-s. This mass flux variation include all flow regimes namely droplet, column and sheet modes. For multiphase flow, volume of fluid (VOF) model is selected, as this model is used where two phases are separated in the flow regime. Wall adhesion model is incorporated for film and tube contact. Conservation of mass, momentum and energy equations were solved in a transient manner via SIMPLE algorithm for pressure-velocity coupling. All equations were discretized in 2nd order and residual for convergence criteria was set to 10-6 for better accuracy. The time step was taken 5 × 10-6 s, to ensure that the global courant number is below 0.25 and iterations for each time step were 40. Initially mesh dependency check was carried out and then the model was validated against available data in the literature. CFD results show that at lower mass flux i.e. 0.03 kg/m-s, tubes are not completely wet and there are dry patches, which are more susceptible to fouling. As the mass flux is increased flow regime changes from droplet to column and then to sheet mode. Increasing mass flux diminishes dry patches problem but also at higher mass flux, film is detached from tube surface causing lower portion of tube to remain dry. There is no fixed critical value for flow regime transformation as it depends on many factors like tube Outer Diameter (O.D.), tube pitch, nozzle type, nozzle diameter and solution properties etc. Moreover, the effect of surface roughness was also taken into consideration and it was concluded that more roughness results in better film stability and enhanced wettability.
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Shallow Aquifer upper ∼120 m Rocks of Qatar: Depositional and Diagenetic Controls on Water Storage Capacity and Hydraulic Conductivity
More LessCarbonates and evaporites of Paleogene-age form the shallow-aquifer rocks that mantle most of Qatar, including the Paleocene and Lower Eocene Umm er Radhuma, and the Middle Eocene Rus and Dammam Formations. Nearly complete 10-cm-diameter rock cores have been recovered from boreholes in central and northern Qatar to depths of greater than 120 m. A 40-m section of exposed Rus and Dammam Formation from a cave in central Qatar (Misfer Cave) was also described. Assessment of aquifer quality in these rocks was undertaken through core and thin-section description, quantitative mineralogical determination (X-ray diffraction), as well as core-plug porosity, permeability, and pore-throat (mercury-injection capillary pressure) measurements.
Our work shows that the rocks from central Qatar can be separated into four depositional intervals: 1) m-scale fining-upward cycles of fossiliferous open-marine deposits with clay-rich caps (Umm er Radhuma), 2) fine-grained stromatolite-bearing, restricted shallow-marine deposits (uppermost Umm er Radhuma), 3) m-scale bedded marginal-marine gypsum deposits intercalated with thin shallow marine carbonate and clay deposits and capped by rooted and microcodium-bearing surfaces (Rus Formation), and 4) open-marine carbonates overprinted by karst processes (Dammam). Aquifer storage capacity and hydraulic conductivity are mostly a function of diagenetic features, and in spite of the lack of any evidence of significant burial, the diagenesis of these rocks is complex. The Umm er Radhuma and the Rus carbonates are almost completely dolomitized, whereas the Dammam is only partially dolomitized, with the amount of dolomitization varying both laterally and vertically. Best aquifer quality in central Qatar, based both on core plug data and well spinner tests, can be found in coarsely-dolomitized intervals that lack clay (lower Umm er Radhuma). Finer and clay-bearing dolomitized rocks have storage but lower hydraulic conductivity (upper Umm er Radhuma). Both gypsum-rich rocks and depositional limestones (which are generally mud-bearing) have lower porosity and permeability (Rus and Dammam). In central Qatar the effect of karst overprinting is variable, generally leading to lower matrix porosity and permeability due to clay translocation from above, but large vugs are also observed at exposure surfaces.
The borehole in northern Qatar was located within a karst collapse feature (doline) that is characterized by internal drainage. Based on satellite images, the collapse feature, likely reflecting the presence of deeper karst is approximately 1 km in width. Sediment tentatively interpreted as a cave deposit, and composed mainly of dolomite silt, has been observed in this core at depths of greater than 60 m below the surface. This fine-grained material intercalates with courser breccias that are interpreted as collapsed country rock. The impact of karstification on country rock matrix properties (porosity and permeability) is still to be determined. Whereas the rocks from northern Qatar are still under investigation, they are distinct from the central Qatar equivalents in that they lack any bedded evaporites. This leads to the prediction that the shallow aquifer in northern Qatar will be less compartmentalized than in central Qatar. The elemental makeup of waters from different stratigraphic intervals in both boreholes are being compared to help understand how the central and north shallow Qatar aquifers contrast.
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Developing a Framework for a Dynamic Modeling Tool to Support RiskBased Decision Making in the Petrochemical Industry
Authors: Rym Kanes, Clementina Ramirez-Marengo, Ali Sheharyar, Othmane Bouhali, Luc Vechot and Emilio AlvarezProcess Safety in the oil and gas industry is managed through a robust process safety management system that involves the assessment of the risks associated with a facility, throughout its lifecycle. Typical approaches for risk assessment of an accident scenario includes: the identification of hazards, the estimation of the frequency, the analysis of possible consequences, and the evaluation of the risk against a company's tolerance criteria. While current quantitative risk assessment methods (e.g.: Layer of protection analysis (LOPA), Bow Tie analysis (BT), etc.) have brought significant improvements in the management of major hazards, they tend to provide static values of risk at a given time (snapshot at the time of the assessment). In reality however, risk levels tend to fluctuate throughout the lifecycle of a process, due to several time-variant risk factors, which include: equipment aging (which impacts their reliability), variations in the integrity and vulnerability of safety barriers, plant activities (e.g.: maintenance, shut-down), health and efficiency of the process safety management system, process safety incidents or near misses, etc. Thus, to that effect, risk is dynamic in nature and risk assessment approaches should allow for continuous updating of risk values over time. Over the last decade, the petrochemical industry has put significant efforts in developing process safety indicators (PSIs) to continuously measure the health and efficiency of process safety management systems. This has increased the sources of information that are used to assess risks in real-time. Hence, there is an opportunity to leverage PSIs along with equipment/safety barrier performance data to estimate the quantitative measure of risk levels in a process facility on a time-variant basis. ExxonMobil Research Qatar (EMRQ) partnered with the Mary Kay O'Connor Process Safety Center – Qatar (MKOPSC-Q) to attempt development of a tool that uses Bayesian Belief Networks (BN) to capture any potential increase of risk levels in real-time as a result of pre-identified risk factors and reliability data of equipment and safety barriers. The tool is referred to as PULSE, which stands for Process Unit Life Safety Evaluation, and is intended to be used to support existing decision making practices. The work involves a phased approach that first included the development of a methodology to establish the framework for the tool. Then, implementation and testing of the framework was attempted using BN algorithms. The most recent phase involves application of the tool to maintenance and inspection planning. In this context, the work presented here demonstrates the feasibility of using PULSE to quantify changes in risk level for a process unit based on a case study from literature. Furthermore, the different aspects of PULSE development are described. These aspects include: translation of the Bow Tie into a BN, modification of the BN to include reliability data, and insertion of equipment failure incidents into the BN to perform dynamic modeling. The outcomes of the dynamic modeling with real time insertion of equipment failure evidence are discussed. Also, the application of dynamic modeling to support risk-based decision making with regards to inspection and maintenance planning is included.
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NASICON based Na4MnV PO4 3/MWCNTs Cathode Materials for Naion Batteries with Improved Electrochemical Performance
Lithium ion batteries (LIBs) have completely captured the portable electronics and electric vehicle market due to their tempting performance. However, due to limited reserves of lithium, the price for lithium is constantly increasing which necessitates to trace out some decent alternative to lithium ion batteries. In this regard, sodium ion batteries are considered one of the best substitutes for lithium ion batteries due to inherited properties of sodium metal like abundance of resources across the globe, ease of availability, economy and environmentally friendly nature. Moreover, sodium ion batteries follow the similar electrochemical principles as the lithium ion batteries which indicates that knowledge and understanding of principles of lithium ion batteries can be utilized for the development of smart sodium ion batteries. In this work NASICON (Na+ super ionic conductor) based Na4MnV (PO4) 3 was synthesized using the sol - gel technique. As prepared Na4MnV (PO4)3 demonstrates an active redox couple at around 3.6 V and 3.2 V during oxidation and reduction process respectively. The pristine Na4MnV(PO4)3 shows good initial discharge capacity ∼ 138 mAh g-1 at 0.05C. However, it shows rapid discharge capacity fading with increasing discharge rate (138 mAh/g at 0.05C and 15 mAh/g at 2C) and poor cycling performance (68.0% of the initial capacity was retained after 40 cycles) with increasing discharge rate. To improve the electrochemical performance of the developed material, Na4MnV (PO4)3/MWCNTS (MWCNTs = 1 & 3wt. %) were synthesized. The initial discharge capacity of these materials at 0.05C was found to be similar to pristine Na4MnV(PO4)3, however, the addition of MWCNTs has resulted in significant improvement in the discharge capacity at high c-rate which can be mainly attributed to the enhanced electronic conductivity of the pristine material. Apart from higher capacity at high c-rates, the addition of MWCNTs has also improved the cyclability of the pristine Na4MnV(PO4)3. A capacity retention of 99.0 % and 98.00% of the initial discharge capacity after 40 cycles is noticed for Na4MnV(PO4)3/1wt.%MWCNTs and Na4MnV(PO4)3/3wt.%MWCNTs respectively. The improved performance of Na4MnV (PO4) 3/MWCNTs cathode materails make them attractive for energystorage applications.
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Gas Driven Fracture during Gas Production using HeleShaw Cell
Authors: Riyadh Al-Raoush, Zaher Jarrar, Khalid Alshibli and Jongwon JungMethane hydrate is considered a potential energy source, with worldwide reserves on the order of 500–10,000 Gt of carbon. The production of Methane from hydratebearing sediments requires hydrate dissociation for releasing mobile methane gas in sediments prior to gas production operation. Existence of even a small fraction of fines can greatly decrease the permeability of sandy sediments, which will affect the gas recovery process. Fines can migrate through or clog the pores of sandy sediments depending on geometric constraints such as the ratio of the size of the pore throat to the size of the fine particle. In multiphase flow, clogging of fines at the pores causes a change in pressure gradient which affects the flow of gas through the pores and might induce gas driven fracture. In the literature, there is a major knowledge gap that needs to be resolved to develop technical and economically viable methane production strategies from gas hydrate reservoirs. A comprehensive understanding of the underlying physical processes such as fines migration, clogging, and gas-driven fracture during gas production in hydrate bearing sediments is needed. Effects of fines migration and clogging on gas flow path and gas driven fracture were studied for Carbon Dioxide (CO2). This was achieved by conducting multiphase flow experiments on brine saturated sand-kaolinite mixtures using 2D Hele-Shaw cell; a common analogous model that has been used to investigate particle displacement process in sediments and has the unique advantage in allowing real-time visualization. The cell consists of two transparent acrylic sheets that are separated by a small gap. The gap between the two sheets is maintained using filter sheets that have a thickness of 1/16 in. (1.6 mm) at the boundaries. Fluids flow radially between the sheets through a port in the middle of the bottom sheet. Multiphase flow experiments are conducted on samples of brine saturated uniform F75 sand mixed with kaolinite at different percentages by weight (0% to 20%). Pressure volume actuator (flow pump) is used to inject brine into the sample for saturation. Following saturation, CO2 is applied to the cell at a constant pressure (2 kPa, 5 kPa, and 10 kPa). Variation of gas pressure is monitored using a pressure sensor that is attached near the port of the cell. The injection processes are recorder using a high resolution digital camera mounted above the cell. Gas pressure was found to increase with increasing fines content, which indicates the clogging of pores by kaolinite particles. Particle image velocimetry (PIV) analysis was conducted using PIVLAB code on MatLab. Velocity vector field and density plots of velocity field were generated to track particles displacements. Particles near the fracture tip were moving at the highest velocity. The results showed three different regimes of gas flow through sediments. For low concentration of fines, the gas percolates through the pores with no major host particles displacement. For a high concentration of fines, major particle displacement occurs and gas driven fractures are created. Gas solely flows through those generated cracks with no observed percolation. Finally, a combination of the two regimes takes place for intermediate fines content.
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Groundwater pollution by petroleumderived contaminants in coastal semiarid environment
More LessA common source of contamination of soil and groundwater in arid and (semi)-arid coastal regions are accidental spills of petroleum products, such as crude oil, gasoline, and diesel fuel. Groundwater pollution by petroleum hydrocarbons is a serious pollution problem that poses hazards to water resources and living organisms including humans. After release to the sub surface, hydrocarbons move downward through the aerobic vadose zone under the force of gravity. Eventually, they reach the groundwater table, where oil overlay promotes the development of anaerobic conditions. The oil phase that occurs as floating product on the water table and as residuum on soil grains provides a continued source supplying hydrocarbons to the groundwater. Accumulations of residual hydrocarbons at or near the water table may undergo smearing due to variations in water table elevation driven by, for example, seasonal changes in recharge and discharge or by tidal forcing in coastal environments. In subsurface environments contaminated by petroleum products, the geochemical conditions near the water table, in particular, the oxygen availability, moisture content, salinity, pH, nutrient concentrations and temperature, are important determinants of biogeochemical processes. Among these variables, the interplay of moisture content, oxygen availability and temperature are critical for understanding the biodegradation of petroleum hydrocarbons in arid and (semi)-arid coastal soil environments. In addition, the fate and transport of hydrocarbons in groundwater also depend on the redox conditions, soil mineralogy and microbial community structure, as well as the availability of suitable electron acceptors and nutrients. We hypothesize that the transition zone between the vadose zone and the groundwater system represents a hot spot for the degradation of petroleum hydrocarbons. This transition zone, however, is a dynamic biogeochemical environment, whose functioning is closely linked to the amplitude and frequency of water table fluctuations. We propose to determine the role of water table fluctuations on the coupled hydrological and biogeochemical processes that affect the degradation and partitioning of petroleum hydrocarbons, under conditions relevant to aquifers. Coastal areas in this regard can function as zones of contaminant mass transfers between aquifers and surface water bodies, but also as excellent spots of in situ bioremediation of contaminated soil and groundwater thanks to coupled hydrological and biogeochemical processes. The main objectives of this project are to: 1) quantify the level of sorption and biodegradation of multi-component hydrocarbons in soil and groundwater; 2) quantify the rates of hydrocarbon biodegradation under oscillating aerobic and sulfate reducing conditions in groundwater contaminated with petroleum hydrocarbons; 3) determine the oxygen dynamics in the vadose zone and groundwater affected by hydrocarbon dispersion under variable water table fluctuation regimes; 4) assess the rates and mechanisms of biogeochemical reactions regulating groundwater nutrient turnover during hydrocarbon spill and its movement under conditions of groundwater table fluctuations; and 5) develop a reactive transport model for groundwater pollution by petroleum hydrocarbons. In this project, we combine the acquisition of integrated physical, chemical and microbial data using uniquely designed process-oriented experimental approaches. The results of this project will significantly add to the quantitative knowledge on the effects of water table fluctuations on the release and degradation of petroleum-derived hydrocarbon contaminants in soil environments that experience both arid conditions and tidally-driven water table fluctuations. The expected results of the research will inform groundwater management and protection in arid and (semi)-arid coastal environments. To quantify the level of sorption and biodegradation of petroleum hydrocarbons in subsurface soils and groundwater (Objective 1), we conducted a series of controlled-laboratory batch experiments under variable salinity, temperature and water chemistry conditions. The soil samples were collected from the eastern coast of Qatar which is close to the North Gas and Al-Shaheen Oil Fields. The initial physical characterization of soil samples showed sand classification with the texture class of sabkhas soil. The results of soil-phase chemical characterization suggested that the dominant minerals of the soil are calcite, dolomite and gypsum and the concentrations of chloride and sodium were found to be high with a chloride-to-sodium ratio of ∼1.6.We used volatile benzene and naphthalene hydrocarbons to determine the sorption and biodegradation rates. The results of sorption experiments showed that naphthalene was adsorbed to the soil more than benzene where the initial aqueous concentrations of benzene and naphthalene were reduced at equilibrium due to sorption by approximately 10% and 75%, respectively. This difference was attributed to the organic carbon-water partitioning coefficient which is higher for naphthalene. We developed a sorption kinetics model to define the sorption isotherm of benzene and naphthalene hydrocarbons for the specific coastal soil collected from Qatar site. The model assumes the two sites sorption to the soil, one site in local equilibrium and the other site on first-order kinetic sorption, and the best fits were found for the Langmuir sorption isotherm type for the used hydrocarbons and soil in this project. In this presentation, we present the results of sorption and biodegradation batch experiments as well as the design of a unique dynamic soil column experiment to understand the dynamic responses of the fate, transport and degradation of hydrocarbons and the soil biogeochemical processes to the relatively abrupt changes in hydrogeochemical and climatic conditions.
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Fines migration and clogging behavior in methane hydratebearing sediments
Authors: Jongwon Jung, Shuang Cao, Riyadh Al-Raoush and Khalid AlshibliThe structure of natural hydrate-bearing sediments that exist offshore or onshore is a combination of coarse-grained sediments and fine-grained particles. During gas production from hydrate-bearing sediments, fine particles may migrate with the flowing fluids within pore space and cause clogging of the pore space of the porous media. Therefore, fine particles play a significant role during methane production from hydrate-bearing sediments as it impact the overall sediment formation performance and production efficiency. The migration of fine particles and its impact on clogging have been investigated in a single-phase flow, but it has not been clearly understood in a multi-phase flow. This research focuses on the study of fines migration and clogging behavior during single and multi-phase flow which can be implicated in gas production from hydrates bearing sediments. Microfluidic pore models that mimic porous media with different pore throat sizes were fabricated and utilized to study fines migration and clogging behavior in porous media. Artificial particles and natural fine particles were selected to represent fine particles. The impact of flow rate, pore-fluid types, particle concentration, and pore-throat to fine particle size ratio was investigated. Fine particles used in this research include polystyrene latex particles, silica, and kaolinite. Pore-fluids used in this study include deionized (DI) water, and sodium chloride (NaCl) brine (2M concentration). The particle concentrations covered from 0.1% to 10%. And the pore-throat widths were fabricated from 40 μm to 100 μm. Single-phase flow experiments were conducted to show that the concentration of fine particles required to form clogging in pores increased as flow rate decreased. The results obtained using polystyrene latex particles provide the insight at a relatively higher flow rate (50 μl/min) than literature studies that fine particles with 2% concentration can migrate in the pore throat without bridge or clogging at the various pore throat and fine particle size ratios (o/d = 2.6∼36.4). Furthermore, silica presents higher critical clogging concentration (0.5% in brine) compared with kaolinite (0.2% in brine) when the pore-throat width equal to 60 μm due to the larger pore throat and fine particle size ratio. On the other hand, the findings show that clogging easily occurred at a lower pore-throat to fine particle size ratio even with a few number of fine particles. In addition, pore-fluid type directly influences the tendency of fine's to form clusters which in turn impacts the clogging behavior. For instance, silica fines clogging easier occurs in brine solution compare within deionized water due to larger cluster size in brine, while kaolinite shows an opposite result which means the kaolinite has higher clogging possibility in deionized water compared within brine solution. On the other hand, findings of multi-phase flow experiments show that fine particles accumulate along the liquid-gas interface and migrate together, which in turn cause bridging or clogging to occur easily in pores. These observations imply that a multi-phase flow during gas production could easily form clogging in pores, in which the flow permeability of porous media decreases even though clogging has not occurred in the same conditions with a single-phase flow. Thus, the permeability of porous media in engineering applications should be estimated by considering relatively easy clogging in pores in a multiphase flow compared to a single-phase flow. Findings of this research show the vital impact of pore-fluids and fluid-fluid interphase on fine particles migration and clogging in porous media. It provides a better understanding of the fines migration and clogging mechanisms. In addition, the results indicate the need to understand the types of fines and fluids in reservoir before evaluating if there will be a clogging potential during gas production from hydrates bearing sediments.
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Invitro conservation of some rare and threatened desert plants in Qatar
Authors: Talaat Ahmed and Mohammed AlsafranBackground A range of natural factors, invasive animals and human activity have been severely affecting stability of the ecosystem, resulting in the annihilation of plants habitats and so plant endangerment or even extinction. In Qatar, urgent action needs to be taken to stop decline of desert plant species as well as an effective strategy should be applied to reverse and save these wild endangered plants. Otherwise, they will be faced with the danger of their extinction in near future. Therefore, it is very important to have knowledge of protection measures, such as replanting and propagating through tissue culture technology, to protect the biodiversity in Qatar. Plant in-vitro culture systems have been used as an alternative approach to propagate and conserve a large number of rare and endangered plant species that show difficulties to be propagated using conventional methods of propagation. It was reported that standard culture environment could be effectively employed for short-term in-vitro conservation of different plant germplasm, through increasing intervals between subcultures especially in slow growing plant species. Objectives In the current study, conservation of rare and endangered desert plants using in-vitro culture were developed. Generally, these plants are not easy to be propagated by classical horticultural methods. Different techniques including micro-propagation, in vitro seed germination, and regeneration from callus were applied to propagate and conserve three endangered plant species in Qatar; Leptadenia pyrotechnica, Glossonema varians and Prosopis cineraria. Methods Collection of endangered plant species Location of the endangered plant species were identified and the plant parts- seeds, stem, shoots, roots, nodal cuttings or whole plant- depending on its type and availability, were collected. Surface sterilization of the collected material The plant materials were washed with tap water to remove dust and debris, then were soaked in 70% ethanol for 1–2 min, then were treated with sodium hypochlorite or Clorox for 10–20 min followed by rinsing 3–5 times with sterilized distilled water under aseptic conditions. In-vitro plants formation Organ culture using nodal sections of the plants were cultured on hormone-free MS medium (0.5X) for in vitro plants formation. For seeds were cultured on medium containing gibberellic acid (GA3) for efficient seeds germination. In this way, in vitro plants were established and multiplied to produce large number of healthy clones. In case seeds or nodal cuttings are not available, other plant parts like leaf or root were used as explants to initiate callus tissues. Results Seeds of Leptadenia pyrotechnica were collected, surface sterilized and germinated under aseptic condition using 0.5X MS media. In-vitro employing tissue culture via callus and shoot induction using different growth regulators was explored. Seedlings from in-vitro germination of the seed were used as explants. The results revealed that the highest callus production was obtained using 2.0 mg/L BAP. In addition, 0.5 mg/L and 2.0 mg/L NAA were good for callus initiation, compared to other hormones. Seedlings of Glossonema varians were collected were used as an explant for callus induction. Several plant growth regulator were used to initiate callus including 2, 4, D, NAA and BAP and their combinations. The results showed that the best plant growth regulators to induce callus were 1.5 mg/l IBA and 2 mg/l BAP. Prosopis cineraria, is a famous tree in Qatar. It is not easy to be propagated by classical horticultural methods. Seed dormancy was broken by scratching via sand paper. Several plant growth regulator were used to initiate callus including 2, 4, D, NAA and BAP and their combinations. The results showed that the best plant growth regulators to induce callus were both 2.0 mg/l 2, 4, D and 1.5 mg/l IBA. The obtained callus will be treated to regenerate new plantlets. Adventitious shoots and roots formation will be induced and a large number of in vitro plants will be produced. The in-vitro grown clones will be hardened (acclimatized) for greenhouse and later field conditions. The in-vitro plants will be removed from the cultures; medium will be removed by washing with running water and sown in pots. The pots will be covered with plastic sheets to keep high humidity and gradual removal of the plastic will harden the plants for greenhouse.Conclusions Recently, in-vitro culture technique of desert plants has received importance because it can be used for the fast propagation and ex situ conservation of endangered plants. The success of micro-propagation and in vitro conservation of the selected endangered plants depends on the best choice of the explants, the efficiency of the sterilization method and correct plant growth regulator. The best in-vitro conservation of the selected plant species is in MS media with the following plant hormones 2, 4, D, NAA. IBA and BAP.
Acknowledgements «This study was made possible by UREP grant # UREP19-209-1-037 from the Qatar national research fund (a member of Qatar foundation). The statements made herein are solely the responsibility of the author(s).»
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CuI and CuSCN as Hole Transport Materials for Perovskite Solar Cells
CuI and CuSCN as Hole Transport Materials for Perovskite Solar Cells Vinod E. Madhavan1*, Ahmer Ali Bozdar Baloch1, Afsal Manekkathodi1, Dhanasekaran Thirunvukkaarasu1, I. Zimmermann2, C. Roldán- Carmona2, G. Grancini2, M. Buffiere1, Mohammad Khaja Nazeeruddin2, A. Belaidi1 and Nouar Tabet1 1 Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, Qatar Foundation, P. O. Box 5825, Doha, Qatar 2 Group for Molecular Engineering of Functional Materials, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, CH-1951 Sion, Switzerland *[email protected]. ABSTRACT: Perovskite based solar cell is an important area of research for solar energy harvesting and for green energy revolution. The materials used for a thin film solar cell are considerably less with respect to the prevailing silicon based solar cells. There is an interest in copper based inorganic materials, especially copper iodide (CuI) and copper thiocyanate (CuSCN) as hole transport materials (HTMs) in perovskite solar cells (PSCs) for efficient, inexpensive and stable energy harvesting. Copper based films exhibit higher conductivity and wider-band-gap. The existing organic HTMs are expensive and have low hole mobility. The reported high power conversion efficiency (PCE) of CuI and CuSCN based perovskite solar cells are 6% and 20.3% respectively [Christians et al. J. Am. Chem. Soc., 2014, N Arora et al. Science 2017]. The perovskite solar cells based on inorganic CuI and CuSCN can be more stable and cost-effective with respect to spiro-OMeTAD HTM. We present our work on mixed perovskite in the form of (FAPbI3)0.85(MAPbBr3)0.15 in combination with CuI and CuSCN HTMs that lead to efficiencies 5.16% and 15.43% respectively in an n-i-p architecture under full sun illumination. The CuI based device displayed a short-circuit current density (Jsc) of 8.98 mA/cm2, Voc of 898.57 mV and fill factor (FF) of 0.64. Under similar conditions, the device with CuSCN, showed a significant increase in the Jsc (8.95 mA/cm2 to 20.86 mA/cm2) and Voc (from 898.57 mV to 1060 mV) (Figure1). A reference cell with standard spiro-OMeTAD HTM showed a PCE of 19.65% (with Voc of 1180 mV and Jsc of 22.70 mA/cm2). The high Jsc when using CuSCN with respect to CuI is mainly due to the effective charge extraction between the perovskite and CuSCN. However there is a strong quenching in the photoluminescence measurements in both CuI and CuSCN cases, which suggests that excellent hole injection is taking place from the perovskite active layer into the CuI and CuSCN hole transport materials (Figure 2). It is worth noting that CuI based perovskite devices showed a PCE of 6% with excellent photocurrent stability and 2 orders higher electrical conductivity that lead to higher fill factors [Christians et al. J. Am. Chem. Soc., 2014]. Impedance spectroscopy measurements revealed high recombination rate in CuI devices [Huangfu et al, Applied Surface Science 2015]. This could explain the low Voc and Jsc despite the quenching of the photoluminescence spectrum in the presence of CuI and CuSCN. Further studies are in progress in-order to find out the origin of the recombination and how to remediate them. Various device structure models (p-i-n and n-i-p geometry) with copper based HTMs are simulated with SCAPS software to find out the efficient structures with minimum losses. The results shows that the CuSCN based cells are more promising and can be used to prepare high efficiency perovskite solar cells. References J.A. Christians, R.CM. Fung, P.V. Kamat, J. Am. Chem. Soc. 2014, 136, 2, 758–764 pp. N. Arora, M. I. Dar, A. Hinderhofer, N. Pellet, F. Schreiber, S.M. Zakeeruddin, M. Grätzel, Science 2017,10.1126/science.aam5655. M. Huangfu, Y. Shen, G. Zhu, K. Xu and M. Cao*,F. Gu and L. Wang, Appl. Surf. Sci. 2015, 357-B, 2234–2240pp.
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Distribution Identification Isolation and Culturing of Cyanobacteria Found in Qatari Microbial Mats and its Applicability for Treatment of Industrial Wastewater
More LessA significant global environmental opportunity of today is finding beneficial reuse for industrial and domestic wastewater through appropriate treatment, redistribution and application. Although industrial wastewater may present various challenges in terms of exotic or hard to treat constituents, finding effective and efficient treatment options and subsequent reuse opportunities will be beneficial for many facets of the environment, especially in regions of the world where water scarcity is an issue. Numerous remediation methods have been developed to purify wastewater. Most of these are physiochemical in nature, which are often not effective to implement on a large scale and can be expensive. This research explores an environmentally natural approach using biological processes (microbial activity) to achieve the degradation of petroleum hydrocarbons. The objective of this study was to study microbes native to Qatar, in particular those found within microbial mats that are found in various areas around the country. The steps taken were to first estimate the area of microbial mats using GIS, identify the microbial species within these regionally specific mats, isolate and culture cyanobacteria from these mats and explore the applicability of using these organisms for treatment of industrial wastewater.
Microbial mat samples were collected from three geographical areas around Qatar, namely Ras Abrouq, Al Zubara and Khor Al Adaid. The collected microbial mats were firstly enriched in cultured medium. Different strains of cyanobacteria were isolated from these enriched mats and were cultured using solid media ASN-III and MN. Single strains of cyanobacteria were then sub cultured in BG-II liquid medium and were used to test the biodegradability of a test set of hydrocarbons (benzene, toluene and hexadecane). The optical densities of the cyanobacteria were measured using a spectrophotometer and the rate of biodegradation of the hydrocarbons were found using a Gas Chromatography Mass Spectrophotometer (GCMS).
Results show that most of the microbial mats identified in Qatar are found on the Dukhan coastline area. Another important area of mats is found at Khor Al Adaid (Inland Sea) located in the southeastern portion of the state. Different species of cyanobacteria were identified from these mats. The most common species identified from mats at Al Zubara were Oscillatoria, Phormidium, Microcolous, Lyngbya, and Spirulina. Those from Khor Al Adaid were Plectonema, Synechococcus, Phormeduim, Lyugbya, Oscillatoria, and Trichodesmium. Those from Ras Abrouq consisted mostly of Microcolous, Lyngbya, Pseudanabena, Oscillatoria, Phormidium, Spirulina, Gloeocapsa, and Aphanothecechroococcus.
Two species of the cyanobacteria, Oscillatoria and unicellular Cyanococcus, were successfully cultured and sub cultured in BG-II medium and used for biodegradation studies with hydrocarbons. Initial results suggest these species are capable of degrading hydrocarbons, but further studies are required to determine to what extent.
For future research, the duration of incubation of microbes with the chemicals of interest for degradation could be increased to help confirm capability. Furthermore, mixtures of different species of cyanobacteria could be used to understand if populations play a role in achieving effective biodegradation of hydrocarbons. This work is also being expanded to explore other microbes found around Qatar and testing their applicability to be effective “biodegraders”. All this research may be beneficial with our larger goal of finding more effective, efficient and environmentally natural approaches to treating industrial wastewater.
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Yeast Volatile Organic Compounds Inhibit Ochratoxin Biosynthesis By Aspergillus Carbonarius and a Ochraceus
Authors: Zahoor Ul Hassan, Maria Farbo, Pietro Urgeghe, Angela Marcello, Samir Jaoua and Quirico MigheliOchratoxin A (OTA) has hepatotoxic, teratogenic, nephrotoxic and carcinogenic effect in mammals and it is classified as a group 2B carcinogen by the World Health Organization. The European Union has set the maximum OTA level at 2 mg/kg in wine, grape juice, and other grape products, and at 3 mg/kg for all products derived from cereal, including cereal products and cereal grains for human consumption. Some species of Aspergillus are the main source of OTA in warm and tropical regions, and in particular Aspergillus carbonarius (Bainier) Thom is considered one of the most relevant OTA producers in food and feed. Inhibiting the growth of OTA-producing fungi on sensitive commodities is by far the most reliable method to prevent OTA contamination of food and feed. Aim of this study was to evaluate the biocontrol ability of selected yeast strains against OTA producing Aspergillus carbonarius and Aspergillus ochraceus. In a previous report, two non-fermenting (Cyberlindnera jadinii 273 and Candida friedrichii 778) and two low-fermenting (Candida intermedia 235 and Lachancea thermotolerans 751) yeast strains have shown a significant antagonistic behaviour against a virulent strain of A. carbonarius on grape berries as well as in in vitro experiments, while the filtrated and autoclaved culture broth of the yeast strains had no significant effect on pathogen growth.This biological effect was at least partly due to the release of volatile organic compounds (VOCs), since growth inhibition was observed without contact between yeast and Aspergillus spp.. Aspergillus colonies exposed to yeast VOCs did not sporulate, and were characterized by a white mycelium; the colony border was undefined, with elongated and scattered hyphae compared to unexposed control. Single hyphal tips and mycelium fragments were then transferred on PDA and after 5 days of growth at 25°C, typical dark sporulating colonies were evident, suggesting that the anti-sporulating effect is reversible. Aiming to further characterise the effect of VOCs produced by biocontrol yeast strains, we observed that, beside vegetative growth and sporulation, the volatile compounds significantly reduced the production of OTA by both A. carbonarius and A. ochraceus isolates. Exposure to yeast VOCs also affected gene expression in A. carbonarius, as confirmed by downregulation of polyketide synthase, non-ribosomal peptide synthase, and the regulatory genes laeA and veA. The main compound of yeast VOCs was 2-phenylethanol, as detected by Headspace-Solid Phase Microextraction-Gas Chromatography-Tandem Mass Spectrometry (HS-SPME-GC-MS) analysis. Yeast VOCs represent a promising tool for the containment of growth and development of mycotoxigenic fungi, and a valuable aid to guarantee food safety and quality. Further studies will aim at testing single purified VOCs in order to identify the most effective compounds responsible for the inhibition of fungal growth and OTA production by Aspergillus spp. in preventive food safety strategies.
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Evaluating the potential of using truck appointment systems to decrease reefer energy consumption at container terminals
More LessIn the recent decades there has been an unprecedented globalization of trade. One of the most important factors that made this possible is the containerization of the supply chain. As a consequence container terminals have become essential for todays globalized economy. The trend of containerization has further extended to the cold supply chain through the use of reefers (refrigerated containers), resulting in a tremendous increase in the trade of food and other perishable goods. In case of import dependent countries like Qatar the cold supply chain has become essential for food security. The number of reefers at container terminals has substantially grown and as a consequence their energy use. In average ports, the largest part of energy is consumed by crane operations and cooling of reefers. In case of ports that are dedicated to export/import of foods the cooling of reefers becomes the largest component of terminal energy consumption. This is especially the case in countries with extreme temperatures like Qatar. Although there has been a substantial amount of research dedicated to optimizing operational procedures of cranes at container terminals with a focus on minimizing energy use, similar approaches have not been explored in case of reefers and the related cold supply chain. In this work we focused on the potential of exploiting a terminal truck appointment system (TAS) to this goal. The main objective of the TAS is to minimize the waiting times at the port gates and to maximize the utilization of container yard equipment. It is important to note that previous research has shown that the information from the TAS can be used to optimize the crane operations. The majority of the existing research on TAS systems has been dedicated to evaluating the potential benefits that such systems can bring to a port in the sense of truck turn times. The concept of including reefer related information into a TAS adds a new dimension to the problem. This is due to the fact that the energy use of a reefer container is directly related to its dwelling time. The idea is to minimize the stay of reefers at the port. To be more precise the objective is to minimize the time since a reefer is unloaded to the port until a truck takes it out of the port. In practice this means that we wish to get the trucks that import the reefers to come to the port as soon as possible. This type of work adds a new type of objective where there is a higher priority related to trucks importing reefers. It is possible to develop a mixed integer program to assist in designing optimal methods for TAS related issues it is often not the best choice. The problem is that due to the high level of unpredictability in the movement of trucks inside and outside of the port the evaluation of a TAS system in this way is often not adequate. Due to this fact, the evaluation of such systems is frequently done using discrete event simulations (DES). In the existing literature the schedule for trucks is fixed, and further analysis is done to evaluate the effect of missed appointments and the percentage of «walk-in» trucks. The DES is only used for the truck arrivals to the port and related use of resources (Entrance Gate, Yard, Exit Gate, etc.). In the proposed research we extend the DES to also include dynamic appointment scheduling. To be more precise, we analyze how requests arrive and how appointments are given. This is important in the context of reefers since we want to give then higher priority, in the sense of leaving appointment slots open for truckers that transport them out of the port, which would otherwise be booked. The proposed DES is used to evaluate several strategies for appointments systems for both minimizing turn times of trucks and the dwelling times of containers. We show that some strategies can notably decrease the energy used for reefer cooling while maintaining short truck turn times.
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Performance of Antisoiling Coatings for Enhancement of PV Panel Performance in Doha
Authors: Maulid Mohamed Kivambe, Benjamin Figgis and Nouar TabetSevere temperature, humidity and dust characteristic of the desert region are major challenges in power generation efficiency of photovoltaic (PV) systems in the gulf region. Soiling can lead to daily average energy loss of up to 4% [1], necessitating frequent cleaning which adds to the cost. One of the solutions to the problem is to use anti-soil coatings, where hydrophilic or hydrophobic coatings with spectral characteristics suitable for PV applications are added to the outer layer of PV glass. However, it has been shown that the effectiveness of the coatings in reducing accumulation of dust in PV panels is dependent on climatic conditions [2-4]. Since coatings add to the cost of solar panels, it is imperative that the coatings are tested for suitability at the intended location or similar weather conditions prior to large scale application. In this work, anti-soil coatings on PV glass were tested outdoor in order to assess the effectiveness of the coatings as remedy for PV performance degradation upon exposure to environmental conditions of the Gulf region. Industrial anti-dust coatings on solar glass and uncoated solar glass; sample size ∼2.5 cm × 2.5 cm, were tested outdoor at Qatar Foundation's solar test facility (STF) in Doha. The coatings were hydrophobic (contact angle pre-exposure 83-90 degrees), while uncoated samples were hydrophilic (contact angle pre-exposure 34 -47 degrees). Measurements were taken pre-exposure (as received) and periodically upon exposure. The measurements were repeated after cleaning, which includes 3 day rain (Rain Clean), wash with free-running deionized (DI) water (DI-Clean), and wash with DI water with scrubbing (DI+S). The main test parameter of interest was radiant energy transmission properties. The impact of wind and humidity on energy transmission and the morphology and composition of the dust particles on samples were also analyzed. The following is a summary of the findings. Performance degradation due to dust is very high. Energy transmission loss of up to 37% was recorded during 13 weeks (week 8-week 20) of exposure, without dust storms (Fig. 1, 2).The advantage of coatings (over uncoated samples) is only marginal. Example, the average periodic energy transmission during week 8 –week 20 is < 1.5% higher for coated samples. Therefore, the tested anti-soil coatings seem not to offer significant remedy to performance degradation due to dust in Qatar. Patterned glass has better transmittance than plain glass, irrespective of coating type. Example, the average periodic energy transmission during week 8 –week 20 of exposure is ∼6% higher for patterned glass. The highest impact of dust in energy transmission is in the wave length range below 500 nm. This appears to be due to the high concentration of small (submicron) dust particles (see SEM images in Fig. 3).Cleaning recovers transmission to pre-exposure levels, except for shorter wavelengths (below 500 nm). This may suggest that smaller dust particles are difficult to remove. In-addition, presence of surface contaminants (non-dust-related) may require aggressive cleaning to remove.Dry wind appears to give a cleaning effect. Example, during W10 –W11, (Fig. 1) a period of fast winds (>2.5 m/s) and low humidity ( < 27%), energy transmission improved (instead of decreasing or remaining un-changed) for most of the samples. The morphology (Fig. 3) and compositions of dust on samples (Fig. 4) appear to be the constituents of the desert dust [5, 6]. However, dust particles exceptionally rich in Carbon (>30%), Iron (2%), Aluminium (>;4%) and Sulfur (>5%) have been observed. These may suggest existence of contribution from environmental activities such as transport and construction [7]. Dust particles with elevated amounts of Chlorine (3%) and Sodium (4%) have also been observed. These may indicate a contribution of salts from the sea [6, 7]. References [1] S. Semaoui, A. H. Arab, E. K. Boudjelthia, S. Bacha, and H. Zeraia, «Dust Effect on Optical Transmittance of Photovoltaic Module Glazing in a Desert Region,» Energy Procedia, vol. 74, pp. 1347-1357, 8// 2015. [2] Z. Abrams, P. Gonsalves, B. Brophy, and J. Posbic, «Field and Lab Verification of Hydrophobic Anti-Reflective and Anti-Soiling Coatings on Photovoltaic Glass,» Proceedings of the 29th EUPVSEC, pp. 2759-2764, 2014. [3] E. Klimm, T. Lorenz, and K. Weiss, «Can anti-soiling coating on solar glass influence the degree of performance loss over time of PV modules drastically?,» the 28th EUPVSEC, 2011. [4] E. Klimm, L. Ost, B. Spiegelhalter, and K. A. Weiss, «Tests of functional coatings on glass adapted to extreme - arid and maritime - climatic conditions for solar energy systems,» in Photovoltaic Specialist Conference (PVSC), 2015 IEEE 42nd, 2015, pp. 1-5. [5] T. Sarver, A. Al-Qaraghuli, and L. L. Kazmerski, «A comprehensive review of the impact of dust on the use of solar energy: History, investigations, results, literature, and mitigation approaches,» Renewable and Sustainable Energy Reviews, vol. 22, pp. 698-733, 6// 2013. [6] B. S. Yilbas, H. Ali, M. M. Khaled, N. Al-Aqeeli, N. Abu-Dheir, and K. K. Varanasi, «Influence of dust and mud on the optical, chemical, and mechanical properties of a pv protective glass,» Scientific Reports, vol. 5, p. 15833, 10/30/online 2015. [7] H. K. Elminir, A. E. Ghitas, R. H. Hamid, F. El-Hussainy, M. M. Beheary, and K. M. Abdel-Moneim, «Effect of dust on the transparent cover of solar collectors,» Energy Conversion and Management, vol. 47, pp. 3192-3203, 11// 2006.
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Experiment supported 2D COMSOL modeling of Fischer Tropsch Synthesis using Nonconventional media and Nonconventional catalyst
More LessFischer Tropsch Synthesis (FTS) is an exothermic chemical reaction in which synthesis gas (or ‘syngas’- a mixture of H2 and CO) is converted into hydrocarbons or value-added chemicals. In this process, a catalyst (typically cobalt based or Iron based) is used in a Fixed Bed (FB) or Slurry Bed (SB) reactor for the conversion process. Qatar hosts both the technologies in its world's largest Gas to Liquid (GTL) facilities (Shell Pearl GTL and Sasol Oryx GTL). Although both the technologies have been commercially implemented in a large scale, further process intensification by radial scale-up has been a challenging task due to certain process limitation associated with transport characteristics of both the beds. In particular, the FB technology has issues related to hotspot formation owing to exothermicity of the FTS process which is significantly better in its SB counterpart. Our efforts in the current study are invested to understand the FB performance when it is radially scaled-up to a higher reactor geometry, and to possibly mitigate the effect of hotspot formation. In particular, the objective of this work is to utilize the merits of nonconventional Supercritical Fluids FTS (SCF-FTS) to consolidate the benefits of both the beds (FB and SB) to address the challenges related to hotspot formation. For this, we have developed a multi-dimensional computational fluid dynamics (CFD) model in COMSOL® to facilitate a high-resolution understanding of both the SCF-FTS and conventional Gas Phase (GP)-FTS from the perspective of bed thermal management. As an extension to our previous modeling efforts in development of 1-D and 2-D FB-FTS model [1-2], we are currently involved in development of a multiscale 2D model to investigate the pore characteristics using both the modes of operation. Comprehensive experimental investigations were carried out at different operating conditions to support the modeling efforts. A conventional cobalt catalyst with inferior thermal conductivity was investigated in both GP-FTS and SCF-FTS. Later, a novel Micro-fibrous Entrapped Cobalt Catalyst (MFECC) with superior thermal conductivity was investigated in both GP-FTS and SCF-FTS. Conventional catalyst operated SCF-FTS conditions gave a very high value (0.90) than its GP-FTS. The MFECC catalytic bed on the other hand when operated in SCF-FTS conditions gave a slightly lower value (0.86), but six-fold % CO conversion than in GP-FTS. MFECC catalytic bed also exhibited higher C5+ selectivity & higher catalyst activity in SCF-FTS. In order to closely understand the intricate difference in thermal performance shown by the MFECC bed compared to conventional FB, we have performed a detailed CFD calculation. Results of the MFECC bed have shown to provide orders of magnitude improvement in bed thermal conductivity and proved its capability to control hotspot formation. In particular, the results of conventional FB at 20 bar and at a gas hourly space velocity of 5000 1/h in a reactor tube of 0.59 inch ID shows hotspot formation of about at the centerline. On the other hand, the temperature rise in MFECC bed for same operating condition was only. Further, a very recent outcome of this work enabled us to investigate the potential of scaling-up the radial geometry of the MFECC reactor to a 4” ID reactor to improve its throughput while maintaining temperature homogeneity in the reactor bed [2]. The proposed study is a part of a broader project involving both experimental and modeling studies, and is performed at multiple stages to enable mitigation of challenges related to reactor scale up, and runaway hotspot formation in a fixed bed FT reaction. References [1] M.M. Ghouri et al., Computers & Chemical Eng. 2016, 91, 38-48 [2] M.S. Challiwala et al., AIChE Journal, (Under Review)
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Density functional theory study of dry reforming of methane on nickel and nickel based bimetallic catalysts
More LessDry reforming of methane (DRM) reaction utilizes CO2, a major greenhouse gas to convert natural gas (mainly composed of methane) to synthesis gas, an important feedstock which could further be converted into valuable chemicals and cleaner fuel. This reaction presents a clear incentive in terms of its positive impact on the global environment and thus it has gained increasing attention in the last couple of decades. The superior catalytic activity of Nickel based catalysts and also their relatively lower costs make them the most promising catalyst for this reaction. However, these catalysts also deactivate rapidly owing to their high susceptibility to coke formation and filamentous carbon deposition. This severe catalyst deactivation is one of the major drawbacks that is obstructing the widespread commercialization of DRM. Several alternative catalysts have been explored for this reaction, including noble metals such as Rh and Ru. Even though these metals are found to be more reactive, as well as more resistant to carbon deposition, their high cost generally hinders their use [1]. One of the techniques that has been proposed to suppress the coke formation on the nickel surface is the substitution of single foreign transition metal atom which could modify the electronic structure [2]. In the current work, we present our exhaustive work on the solid state density functional theory (DFT) model results to study the wide network of elementary reactions comprising the DRM reaction on various facets of pure nickel catalyst, such as Ni(111) and Ni(100) surfaces. Calculations were performed using rev-PBE as exchange-correlation functional within the generalized gradient approximation (GGA) as implemented in the software VASP. Adsorption energies were calculated for all the DRM reaction intermediate species and then subsequently the activation barriers were calculated for all the elementary reactions in the DRM cycle. The catalytic activity of these pure nickel surfaces in terms of DRM reaction rate are then compared to the rates obtained on the single overlayer deposited nickel (X/Ni) surfaces where X is a transition metal such as Cu, Rh and Pd. Electronic structure analysis of various pure as well as overlayer modified surfaces is performed in terms of the d-band theory of catalysis. Our results indicate that the catalyst stability is greatly improved by a transition metal overlayer deposition on nickel surface. The carbon adsorption energy on a catalyst surface could be a good thermodynamic descriptor for estimating the coking tendency of this particular surface. One of the ways proposed in the literature to improve the coking resistance of a catalyst is to weaken the carbon adsorption energy. From a thermodynamic point of view, the decrease in the carbon adsorption energy on a catalyst surface would lower the surface coverage of carbon. This leads to a lower affinity for carbon deposition and an improvement of the coke reasistance of the catalyst. Our initial results indicate that the most stable adsorption energies of carbon on pure nickel surfaces are of the order of − 7.5 and − 8.96 eV respectively for the (111) AND (100) surfaces. Whereas, for the copper modified (111) and (100), the similar adsorption energies are of the order of − 5.62 and − 7.12 eV. This clearly shows that the copper modified nickel surface show an improved resistance for coking tendency and have lower affinity for carbon deposition.
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Polyelectrolyte membrane PEM and fuelcell catalyst studies using a miniaturized PEM fuel cell test fixture
Authors: Stephen Creager, Saheed Bukola and Rhett SmithAdvances in catalyst and electrolyte materials for hydrogen fuel cells are driving performance gains and cost reductions that are helping to bring hydrogen fuel-cell technology to market. Research on new materials is always a combination of synthesis and characterization, where characterization must eventually include incorporation of materials into an operating fuel cell. It is at this stage that research on leading-edge new materials often stalls, because conventional fuel-cell tests require relatively large amounts of material, e.g. several grams of a new catalyst and tens to hundreds of grams of ionomer, corresponding to many tens of square centimeters of membrane area, are required to run a comprehensive set of tests as is necessary to assure reproducibility and examine behavioral trends. These amounts of material are often not available in early-stage synthetic work, which means that characterization uses other approximate approaches, e.g. rotating disk electrode (RDE) voltammetry to study catalyst activity, with true fuel-cell testing often being delayed until syntheses may be scaled up. This situation is unfortunate because approximate tests often do not adequately screen materials. It would be desirable to run preliminary fuel-cell tests at an early stage to gain a better idea of materials properties before making decisions regarding which materials to scale up. This contribution will present our recent work building and using a miniature PEM fuel-cell test fixture that uses only very small amounts of material to conduct a true solvent-free fuel-cell test. The cell is fabricated from a conventional compression-style fitting and uses 5/8 inch diameter graphite or metal rods for gas delivery and for making electric contact with the electrodes. Membrane-electrode assemblies (MEAs) are made from 3/4-inch diameter PEM disks, typically cut from Nafion ionomer membrane, onto which carbon-cloth-based electrodes are bonded by hot pressing. Electrode diameters range from 1/8 to 3/8 inch. The presentation will include recent published work demonstrating reproducibility and select MEA characterization data, including in-situ voltammetry to assess electrochemically active surface area (ECSA) of catalysts and polarization curve measurements that are easily obtained using conventional linear sweep voltammetry with a conventional laboratory potentiostat. This situation is in contrast to conventional fuel-cell testing that requires specialized instrumentation with passage of very large currents, e.g. tens of amperes. Very recent work using the cells in hydrogen pump configuration will also be presented. This configuration is particularly useful for measuring resistances to proton transport through ionomers in the direction through the membrane plane, in contrast to most measurements which focus on in-plane resistance, because it is easier to measure. Very recent work on the synthesis and properties of new tetra-aryl-phosphonium (TAP) alkaline ionomers which are expected have high alkaline stability and to be good hydroxide-ion conductors, and on the effect of single graphene layers embedded in Nafion membranes on proton and other ion conduction through the Nafion membranes, will also be presented.
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Impacts of DFIG Reactive Power/Voltage Control on Power System Oscillations through Mode Coupling
Authors: Wenzong Wang and Garng HuangIntegration of converter-control based renewable generators (CCBGs) into power systems introduces new dynamics and influences system stability. One particular concern is its impact on power system oscillations. Among different types of CCBGs, doubly-fed induction generators (DFIGs) have attracted the most attention. Reference [1]–[3] use the DFIG model with detailed control loops developed by General Electric (GE) and study its impact on power system small signal oscillations. It is observed that the DFIG reactive power/voltage control loop introduces an oscillation mode whose frequency is in the range of electromechanical oscillations (0.1 Hz to 2 Hz) [1]. DFIG's influence on the electromechanical oscillations is found to be highly dependent on parameters of this control loop [1, 2]. In [3], eigenvalue analysis is conducted for the Western Electricity Coordinating Council (WECC) system with projected high CCBG penetration conditions. An oscillation mode involving both wind turbine and synchronous generator (SG) state variables is observed. It is found that the wind turbine reactive power/voltage control variables have the highest participation in this mode. The observations in [1]–[3] indicate interactions between the DFIG reactive power/voltage control mode (referred to as VAR controller mode hereafter) and the SG electromechanical mode. However, the mechanism of the interaction and the conditions for strong interaction is not explored. Moreover, how this interaction affects the mode shapes of the two modes is not studied. Since the CCBG mechanical dynamics are separated from the grid by the converter interface, coupling between the CCBG converter control modes and the electromechanical modes becomes a critical way by which the CCBG dynamics can influence the electromechanical oscillations and it deserves through study. Based on the mode coupling theory, this paper reveals the interaction mechanism between the VAR controller mode and the SG electromechanical mode. Impacts of this interaction on power system oscillations are demonstrated and discussed. First, the VAR controller mode is investigated using damping torque analysis. Impact of operating condition change on its damping and frequency is shown analytically. The coupling between this mode and an electromechanical inter-area mode is then explored in a two-area test system. It is demonstrated that when frequency of the VAR controller mode approaches the inter-area mode, mutual participation increases and the influence of DFIG dynamics on the inter-area mode is increased. Additionally, it is shown that both positive and negative effect on the inter-area mode damping can be imposed depending on the VAR controller parameters. Moreover, the influence of mode coupling on mode shape of the two modes is investigated and it is demonstrated that the VAR controller mode, if becomes unstable, can couple with a well damped inter-area mode and cause unstable inter-area oscillations. In other words, in this situation, the unstable local voltage oscillation at the DFIG wind farm will propagate to other areas of the system and cause detrimental effect to the system. This study has practical merits. Challenge of wind generator voltage control on weak grids has been identified in the Electric Reliability Council of Texas (ERCOT) system [4]. Voltage and power oscillations close to a wind power plant were observed in ERCOT, following the outage of a nearby transmission line [4] or update of its controller settings [5]. Voltage controller is identified as the source of oscillations [4, 5]. The study in this paper offers insights into the VAR controller mode and demonstrates that not only local oscillations, but also inter-area oscillations can be caused by improper setting of the DFIG VAR controller or change in system operating conditions close to the DFIG plant. The key findings and conclusions of this study are summarized as follows: The DFIG VAR controller mode is sensitive to the system operating condition close to the wind generator. The voltage control scheme of DFIG is more prone to instability than the reactive power control scheme and the damping of the VAR controller mode decreases when the system becomes weaker at the DFIG interconnection point.When frequency of the VAR controller mode approaches an inter-area mode, the followings are observed: 1) mutual participation of the two modes increases; 2) the influence of DFIG dynamics on the inter-area mode damping increases; 3) mode shape of the VAR controller mode changes to involve inter-area oscillation of the SGs. When mode coupling is strong between the two modes, unstable inter-area oscillations can be caused by two mechanisms: 1) a stable VAR controller mode contributes negative damping to the inter-area mode 2) the VAR controller mode becomes unstable and couples with a sufficiently damped inter-area mode (change in VAR controller mode shape) and cause inter-area oscillations. Both situations can be severely detrimental to the system and should be carefully studied to avoid them.Proper settings of the VAR controller can also increase the inter-area mode damping. Results of this study can be generalized to other types of CCBGs since they have the same VAR controller structure (based on models in PSS/E). Thus the potential coupling between the VAR controller mode and the inter-area mode is generic for CCBGs. [1] G. Tsourakis, B. Nomikos, and C. Vournas, “Effect of wind parks with doubly fed asynchronous generators on small-signal stability,” in Electr. Power Syst. Res., vol. 79, no. 1, pp. 190–200, 2009. [2] L. Fan, Z. Miao, and D. Osborn, “Impact of doubly fed wind turbine generation on inter-area oscillation damping,” in Proc. IEEE Power Eng. Soc. Gen. Meeting, 2008, pp. 1–8. [3] J. Quintero, V. Vittal, G. T. Heydt and H. Zhang, «The Impact of Increased Penetration of Converter Control-Based Generators on Power System Modes of Oscillation,» in IEEE Transactions on Power Systems, vol. 29, no. 5, pp. 2248-2256, Sept. 2014. [4] S-H. Huang et al. “Voltage Control Challenges on Weak Grids with High Penetration of Wind Generation: ERCOT Experience,” in Proc. IEEE PES General Meeting, San Diego, CA, July 2012, pp. 1–7. [5] Technology solutions for wind integration in ERCOT, [Online]. www.electrictechnologycenter.com/pdf/TPR2Rev0Chg0043014.pdf
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Improve the production of two Qatari date palm cultivars ShiShy and Lulu for food security
More LessThe response of plant tissue to standard growth media varies widely due to the genetic diversity of the plant cultivars studied. The objective of this research was to determine the effects of micronutrients on date palm growth and which of these micronutrients are critical for improving growth combined with Paclobutrazol or without on in vitro of elongation stage. In vitro growth of two cultivars was determined by varying five treatments that included minor salts (EDTA-chelated iron, Cuso4,) alone or combined with Paclobutrazol. The effects of these five treatments of plantlet length, trunk thickness, rooting number and Chlorophyll A, B were investigated. The results obtained after three months showed that, increase copper sulphate on MS elongation media combined with Paclobutrazol was more effective for increasing strongly of trunk thickness as well as rooting number compared with normal MS level. While poor response was found when increase of Fe in the chelated form of Fe-EDTA on MS elongation media. For cultivars, shishy gave the highest plantlets length as well as root number, while the increase of trunk thickness was achieved with cultivar LuLu. The greatest formation of chlorophylls A, B was observed when increase copper sulphate on MS elongation media with cultivar LuLu. The survival rate after 3 months was related to the medium used during the elongation phase, the survival of plantlets reached to 98.66% with cultivar lulu at the acclimatization stage.
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Initial Results from a Study on Greywater Reuse in Qatar: Economic Benefits and Public Opinions
Authors: Jordan M. Lee and Dr. Laurent A. LambertDue to low annual rainfall and depleted groundwater resources, Qatar relies on expensive and energy-intensive desalination and retreatment plants to meet its growing water demand. With a high consumption rate of 557 liters/day/inhabitant, the cost of desalinating, transporting, and retreating water represents an unnecessarily large financial burden for the state. The Tarsheed national awareness campaign and tariff increases in Qatar are helping temper the rise of these costs, but additional tools are required to counter growing water demand. This study explains how recycling greywater can mitigate the growth of Qatar's water expenditure by slowing the increase in demand for desalinated seawater and retreated wastewater. Greywater is gently used water from showers, washing machines, swimming pools, air conditioning units, and lavatory sinks. Greywater is distinct from more heavily polluted blackwater, which comes from toilets, kitchen sinks, and dishwashers. Recycling greywater can generate savings because, with little or no treatment, greywater can replace more expensive water resources for several purposes, especially garden irrigation and landscaping. For example, using greywater instead of desalinated water for landscaping can slow the growth of demand for desalinated water in Qatar, thereby tempering the increasing cost of desalination subsidies. Capturing and reusing greywater will also slow the growth of the quantity of wastewater that is transported to retreatment plants and purified, which will generate further savings for the state. While there is a small cost to install a greywater capture and treatment system on a building, it pales in comparison to the cost of the desalinated and retreated water that would otherwise be used. This study provides quantitative information on the annual savings that can result from recycling different percentages of Qatar's greywater resource. Savings were calculated by assuming a quantity of greywater to be recycled (ranging from 5% to 30% of total greywater in Qatar), and then determining the cost of desalination, transport, and retreatment for that quantity of water. The savings from recycling the selected quantity of greywater equal the sum of the desalination, transport, and retreatment costs. Using this process, this study finds annual savings ranging from QAR 50 million to QAR 755 million. The large range in savings estimates is due to differences in the amount of greywater recycled, and differences in cost estimates for desalination and wastewater transport and treatment. Cost data were collected through interviews with water provision stakeholders, from executives to workers in the field, as well as a review of literature on the industry. In addition to this economic analysis, this study uses SESRI survey data to show that Qatar's population is highly accepting of greywater use, with 82% of Qatari citizens and 91% of white-collar expatriates saying that they are wiling to use greywater for landscaping. The survey was conducted by telephone and includes data from a nationally representative sample of 746 Qatari citizens and 740 white-collar expatriates. The findings of this research align well with those of greywater research projects in Oman, which have concluded that recycling greywater will generate notable savings, and that there is strong public support for use of the resource. By recycling greywater, Qatar can slow the growth of its water provision costs, improve its water security, and advance its goal of sustainable development.
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An Integrated Approach for Enhancing Food Safety in Qatar
This study was carried out to assess hygiene conditions, food handling practices, food safety knowledge of food service providers (FSPs), and the microbial quality of food served in different food service establishments in Doha. Fifty-three FSPs were randomly selected among 200 FSPs. Face-to-face interviews with the food safety managers at each participating FSP were conducted using a survey consisting of 40-questions (demographic data on workers, HACCP training, knowledge on personal hygiene, and safe-food handling practices) in October-December 2015. In addition to survey questionnaire, a checklist was used to determine the implementation of international food safety standards by observing actual practices applied at each FSP. All FSPs who took part in the initial survey were also invited to participate in one of three one-day educational workshops focused mainly on important components of food safety management system and held in 2016. At the time of workshops, each participant was also encouraged to take part in the microbial quality assessment study. Out of 53 establishments, only 10 FSPs (2 fine-dine-in, 2 casual sit-in, 2 catering, 2 fast-food, and 2 takeaway) accepted to provide food and swab samples from their entities. At the time of each visit to select FSPs, various menu items (food cooked in a short time, ready-to-eat foods, vegetables, dairy-based deserts, sandwiches, and raw seafood, e.g. oysters) were sampled in duplicate (based on the daily menu prepared at the time of sampling) at different food preparation stages (receiving, food storage, food preparation, holding/cooking, and serving). The microbial quality of food samples (n = 105) served and swabs collected from food preparation surfaces (n = 58) were also assessed using select media (APC, MCA, XLT4, and LSA). The identification of positive samples was carried out using VITEK-2 system. After the microbial assessment, a follow-up survey consisting of 24 questions was developed to determine the impact of the educational trainings on food service providers' daily operational practices. The FSP managers who participated in the initial survey were invited by phone or email or in person to take part in the follow-up survey. Out of 53 FSPs, only 16 were available to answer the questions due to reasons beyond the control of the research team. The major reasons for a low participation were 1) several managers moved back to their country without any contact information, 2) many of them changed their jobs and there was a no way of communicating with them since they did not provide an alternative email or a phone number. The survey results indicated that average service years of FSPs was 11, the average age of food safety managers interviewed was 33, most managers (66%) had college degree, and 68% of them were trained on HACCP. It was demonstrated that casual-sit-in and fine-dine-in restaurants are the only FSP types which consistently kept records (100%), followed by fast-food (36%), and catering (14%) FSPs. The microbial analysis indicated that the average APC in food samples collected from all FSPs met the international standards, while the APC counts of swab samples were considered unsatisfactory since the levels were above 106 Log10 CFU/cm2. The highest bacterial count was reported in swab samples (7.26 Log10 CFU/cm2) collected from preparation area in takeaway restaurants. Concerning the target organisms (Escherichia coli, Salmonella spp., and Listeria monocytogenes), among 105 food samples and 58 swab samples collected, 13 samples (8%) exhibited positive results for possible target pathogens. Positive samples were identified as Klebsiella pneumoniae, Klebsiella oxytoca, Pseudomonas aeruginosa, and Pantoea spp. Overall, the participants were highly satisfied (average score: 4.39/5 ± 0.20) with the information presented in the training workshops held in 2016, indicating that the workshops helped improve their knowledge on food safety; change their attitudes towards safe handling foods, and inform them about the changes on food safety laws and regulations in Qatar. These results provided insight information on the aspects of behavioural changes that confirm the value of intervention studies. One important note which is important to mention that the participating managers indicated that they need open communication between the policymakers and the FSPs to be able to make sure that they will not be left behind if there is any changes/updates on food safety rules and regulations applied in the country. This issue is going to be addressed by posting constant updates on GSO (food safety standards applied in Qatar) on the website recently developed and hosted under the Ministry of Public Health website. Results obtained in this study might help food safety managers in these select FSPs to better understand the need for implementing effective control measures in order to prevent contamination and eventually protect the public health.
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A Behavioral Approach to Food Waste Issue in Qatar
Introduction: Food and Agricultural Organization (FAO) defines food security as stable access to sufficient, safe, and nutritious food. Food waste is a global and complex problem that affects each of three pillars of sustainable development: environment, economic, and social (FAO, 2013). Food loss is defined as the decrease in quantity or quality of food, whereas food waste is the removal from the food supply chain of food which is fit for consumption, or which has spoiled or expired mainly due to economic behavior, poor stock management, or neglect (FAO, 2014). Food loss occurs upstream of the supply chain, particularly post-harvest losses have drawn attention. On the other hand, food waste is observed more frequently downstream the supply chain, specifically at the retail and consumption stages. The FAO estimates that around one-third of edible parts of the food produced for human consumption in the world get lost or wasted globally, which correspond to about 1.3 billion tons of food per year. Food waste is closely associated with food security as being able to reduce food waste will help feed more people and reduce the pressure on natural resources whilst alleviating the negative impact on environment due to greenhouse gas emissions from food chain operations and loss of biodiversity due to agricultural activities. Especially in developed countries consumers are considered to be one of the main sources of food waste and therefore in the past few years an increasing number of studies has examined food waste and consumer behavior. The food waste cannot be explained by a single behavior, but rather a combination of multiple behaviors that can increase or decrease the likelihood of food being wasted. The aim of this research is to synthesize the existing work on consumers' food waste behavior and to develop a comprehensive conceptual framework and to empirically test this framework with data from a country that is dependent on foreign food imports, leading to growing concerns about food security: Qatar. With an increasing population and the food provision depending on imports that comprise more than 90% of the food consumed in Qatar, food security is a top priority. This paper is a research outcome of the SAFE-Q Project, which aims to contribute to food security efforts in Qatar with a holistic approach to understanding food distribution, food consumption, and food waste.
Research Approach: Our synthesis of previous work explaining the food waste behavior suggests that the Theory of Planned Behavior (TPB) sets a strong basis for explaining it. The TPB provides a theoretical framework that is commonly used for systematically explaining behavior (Ajzen, 1991). We build a conceptual framework extending the TPB (personal attitudes, subjective norms, perceived behavioral control, intentions, behavior) with six additional constructs identified through our extensive literature review and empirical work in Qatar: motives, financial attitudes, planning routines, social relationships, food surplus, and Ramadan (Aktas et al., 2017). We developed an online questionnaire and collected data from Qatar in English and Arabic. We then used partial least squares structural equation modelling to explain the food waste behavior. Results and Discussion In line with the TPB, we find a negative relationship between perceived behavioral control and intentions, where the perceived behavioral control construct has indicators measuring the “difficulty to control food waste”. The relationship between intentions to reduce waste and the amount of food waste is negative, where we conclude the intentions to reduce waste help reduce the behavior leading to food waste. The positive relationship between personal attitudes and intentions suggest that attitudes towards food waste positively affect the intentions to reduce food waste. We find a strong negative relationship between perceived behavioral control and intentions to reduce waste. When it is difficult to control the food waste, the intentions to reduce it are low. Both food choice motives and financial attitudes positively affect the planning routines. While planning routines help reduce the food surplus, the social relationships construct that reflect hospitality and eating with others result in higher food surplus. A unique finding of our research is that the contextual construct Ramadan is found to be positively associated with food waste behavior. Understanding the contextual variables which affect consumers' food waste behavior could help developing strategies for food waste reduction. The findings reveal the strong impact of changing eating habits during certain periods of the year (Ramadan) and food surplus on food waste behavior. The food surplus as a contributor to food waste is explained by planning routines and social relationships (hospitality, risk averseness towards not having enough, cultural habits around how food is served). Impact and Conclusion Food has a significant role in economic, social, political, and cultural lives. By adopting or avoiding certain behavior patterns regarding food, individuals can contribute significantly to environmental, social, economic, and political sustainability. Therefore, it is important to understand the motivational and structural factors and processes that facilitate or are barriers to reducing food waste behavior. Our research helps increase the awareness around food waste and maybe used as a lever to change consumer behavior towards reducing surplus food at households, which is wasted if not consumed in time. Minimizing the surplus food wasted at the end of the value chain is the most impactful objective since it minimizes the loss of the highest value added after food is grown, harvested, processed, packaged, stored, transported, and distributed.
References
Ajzen, I. (1991). The theory of planned behavior. Organizational Behavior and Human Decision Processes, 50(2), 179‒211.
Aktas, E., Topaloglu, Z., Oledinma, A., Sharif, A., Huda, A. K. S., Sahin, H., and Irani, Z. (2017). Contextual Factors Affecting Food Security: A Behavioural Framework. In: The 22nd Logistics Re- search Network Annual Conference and PhD Workshop. 6–8 September, Southampton, UK.
FAO (2013). Food wastage footprint. Impacts on natural resources. Summary Report. http://www.fao.org/ docrep/018/i3347e/i3347e.pdf. Date accessed: 31 October 2017.
FAO (2014). Definitional Framework of Food Loss. Working Paper. http://www.fao.org/3/a-at144e.pdf. Date accessed: 31 October 2017.
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Isolation of Qatari bacterial bioagents that have unique characters from date palm environment
Authors: ALI El Kharbotly, Noha El Badawy, Marwa Saadaoui, Mohammed Hassanein and Masoud Al-MarriIdentification of biological agents which is thermo- tolerance is a key success for biological control in the arid regions such as Arabian Peninsula. Date palm is one of the indigenous plants in this region. It can tolerate high temperature and survive the drought. It is expected that microbial communities associated with date palms would have similar characters. It would be reasonable to search for bio-agents from such microbial communities. This study is a apart of a project to identify microbial communities living in the phyllosphere and rhizosphere of date palms. Bacterial colonies were isolated from date palm leaflets and soil samples containing date palm roots. Samples were collected from the date palm experimental field at the Agricultural Research Farm, Rwdet Al-Faras, Qatar. Isolation of bacteria were conducted on nutrient agar media using the standard techniques. Hundred eighty five bacterial isolates were obtained. They were evaluated for their antagonism potentiality against Alternaria alternate as a causal agent for leaf spot diseases in date palm and Fusarium solani and Macrophomina phaseolina as causal agents for root rot in Phaseolus vulgaris crops. Suppression of mycelial growth of the pathogens were recorded as the result of the interaction between the pathogen and different bacteria. Two modes of action were observed. Eleven isolates grew on the area of inoculation but they suppressed the pathogen by their extracellular antifungal metabolites while the growth of 18 isolates spread all over the plate and prevented pathogens from growing either by their growth or by both the growth and the extracellular antifungal metabolites. Screening for thermos-tolerance were carried out by picking up a single colony from each bacterial isolate, inoculating it in 1 ml of LB liquid media and incubating the culture at 90 °C for 24 hours. Then they were cultured on nutrient agar media plates, incubated at 30 °C for 24 hours. The two separate evaluations of antagonism and thermos-tolerance of the bacterial isolates showed that only 18 isolates had both characters. These 18 isolates were exposed to high temperature then evaluated for their antagonism. Only 7 isolates kept their potential to suppress the growth of pathogens. This test demonstrated the possibility of losing the antagonism effect as a result of high temperature. In this test 90 °C/24 hours was used. Molecular identification was carried out to on the seven bacterial isolates. They were identified based on 16s rDNA sequencing using universal primers and standard procedures. They were Pseudomonas putida (3 isolates), Bacillus subtilis (2 isolates) and Bacillus megaterium (2 isolates). These species were reported to have a potential as a bioagents and some of their isolates were developed and being used commercially as biopesticide. We do not recommend using Pseudomonas putida as biopesticide because they might have a potential risk for human. They can cause infections in cases of immunocompromised patients It can be concluded that both thermos-tolerance and antagonism are important to have a successful bio pesticide in the arid region. Losing the antagonism after exposing to high temperature showed the importance of evaluating each bio-agent for this character. So far we did not elucidate the mechanism of losing the antagonism. In this experiment, a very high temperature for long time was used however using lower temperatures for shorter periods can reveal different results.
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Establishment of an Efficient in Vitro Regeneration Protocol for Mass Propagation via organogenesis of Endangered Plant Rhanterium epapposum in Qatar
Authors: Fatima hassan Ibrahim, Maha Talib Alhenzab and amira Omer ElbadawiWild plants make an important contribution to the life of localcommunities. Endangered plant species like Rhanterium epapposum olive (Arfaj) were micropropogated through tissue culture technique in order toprotect them from extinction and conserving Biodiversity in Qatar. Agriculture Research Department (ARD) has developed anefficient protocol for rapid and large scale in vitro propagation of the nativeannual plants Rhanterium epapposum that cannot be propagated on alarge-scale by means of seeds and cuttings. Apical bud and nods were collectedfrom wild habitat and cultured on modified Murashige and Skoog (MS) mediumsupplemented with 1.5 mg l-1 BA (initiation stage) and containing 1 mg l-1 BAP+0.2 mg l-1 Kinetin for multiplication stage, reculture three times withregular transferring to fresh medium containing the same composition medium.For rooting stage, elongated shoots were cultured on differentstrength of Murashige and Skoog (MS) media(full and ½) supplemented with different auxin. ½ MS nutrient medium containing1 mg l-1 IBA increased significantly the number of roots and root length compared with othertreatments. The plantlets were adapted to greenhouse conditions successfully
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Directload control experiments and case studies in Qatar Foundation Community Housing
More LessEnergy security is one of the main national concerns, with population's growth and energy demand increase it becomes critical for countries to address the issue. Increasing energy production is extremely costly and could require investments to modify the power network infrastructure that is also expensive. Demand Side Management is a collection of methods and strategies that helps modifying the demand of consumers in order to cope with the limited energy production, avoiding tremendous expenses. DSM is often associated with the residential load profile in order to determine two aspects. Firstly the residential energy load profile is the main component that is required in order to understand how to apply DSM effectively. The load profile is often too complex, it exhibits unique patterns and characteristics as it is influenced by a number of social and economic factors, climate and the local policies also impacts the profile. Secondly the residential load profile has a useful role that helps us identify the viability of using solar photovoltaic and storage systems in households. The residential energy consumption represents a large portion of Qatar's total energy consumption and it is growing larger. By monitoring the energy profiles of 10 households chosen from different accommodation types, we can log and plot actual load profiles that can represent the domestic household energy profile of a province. The monitoring of the loads has to cover a yearlong period in order to demonstrate the climate impact on the load profiles. The energy consumption is represented by household appliances and mostly by HVAC or heating depending on the country's location. The loads are split into two categories, an elastic load that can be fixable for the user to operate at various times. The other type of loads is inelastic loads that have priority that impacts the comfort level of the user and cannot be shifted. These loads play a role in determining the shape of profile and the extent of degree to which it can be changed. The best way of monitoring the loads is through nonintrusive appliance load monitors in order to keep occupants disturbance at minimum. Smappee is a nonintrusive appliance load smart monitor that offers precision in energy reading as well as a remarkable user interface. These monitors measure the total energy consumption using current transformers. It logs power readings with a five minutes interval and uploads it to the cloud. The data can then be downloaded to a local server in order to be plotted into the load profiles. Ten Smappee monitors were installed in ten different houses and apartments in Doha during June and July 2017 and are expected to run for a year. The data will be used to plot a representation of Qatar's typical domestic load profile and to investigate the two aspects of DSM and the viability of PV and storage systems. A simple case study is carried out to assess the potential of DLC in the Education City Community Housing (ECCH). The ECHH accommodates the QF employees in a high-quality villas and apartments that ensure a high living standard. The ECHH consists of two lots that made of totally 639 housing units classified into five different dwelling types. Furthermore, the AC units installed have three different capacities (18, 11, 8 kW) and the capacity of the AC unit depends on the type of the housing unit. Table 1 EC Community Housing units by type of unit, area, and AC unit capacity Housing Type Area (m2) No. of Units AC Load (kW) Total Load Standalone V. Type 1 408 52 18 936 Standalone V. Type 2 389 17 18 306 3 Bedroom Attached V. 315 118 11 1,298 2 Bedroom Attached V. 219 108 11 1,188 3 Bedroom Apt. 256 72 11 792 2 Bedroom Apt. 161 200 8 1,600 1 Bedroom Apt. 109 72 8 576 Figure 1 Peak demand reduction achieved by the three different scenarios in the total electricity demand in Qatar.The case study comprises three scenarios; the first scenario is assuming 15-minute cycling for all buildings is performed. The second scenario is assuming 50% of the residents went on summer vacation, and their AC is cycled for 1 hour and 50% stayed here and their AC is cycled for 15 minutes in 4 groups such that the first group is cycled in the first 15 minutes of the hour, then the second group in the second 15 minutes of the hour and so on. It is believed that more than 50% of the residents leave the country for summer vacation, so the third scenario is similar to the second however, it is assuming 80% of the residents went to summer vacation and 20% stayed in Qatar. The results of these three scenarios are presented in Figure 1. Around 1.674 MW demand reduction could be achieved in the first scenario, while it could be increased if the long summer vacations are taken into consideration as seen in the 2nd and the 3rd scenarios where 3.557 MW and 5.44 MW demand reduction is achieved respectively. Such results provide critical insights in assessing demand reduction potential of Qatar and determining associated economic savings.
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Reinforcement of copolyamide membranes for water treatment applications
Authors: Patrik Sobolciak, Aisha Tanvir, Anton Popelka, Mohamed Hassan, Khaled Mahmoud and Igor KrupaClean water is the key element for all living organisms to sustain life. However, due to the rapid industrialization and large increase in the population, the contamination of water resources is important issue occurred globally as well as locally here in Middle East region [[1]]. From past few decades, various techniques for treating the wastewater have been developed. Among others, filtration techniques are a commonly used to eliminate contamination of water caused by various materials such as heavy metals, dyes, oil, bacteria etc. Robust, capable membranes are crucial for effective filtration process and various polymeric materials have been studied in last decades. Among others, polyamides membranes have been used as membranes due to their favourable properties such as good thermal and mechanical stability [[2]], which make them suitable for the designing of fibres, mats and membranes. Compared to many commercially available filtering membranes that are produced by conventional fabrication techniques such as phase inversion technique, the pore size distribution of electrospun fibrous membranes can be conveniently tailored in the range of sub-microns up to a few micrometers via simply adjusting the material and process parameters of electrospinning and related post-processes. In addition, electrospun filtering media are also capable of maintaining a high porosity, which guarantees the high-flux liquid filtration.One of the approach to further improved efficiency, mechanical performance and lifetime of membranes is using various fillers.Nanocelluloses are particularly interesting because of their environmental friendliness, high mechanical performance, flexibility, low-cost, versatility, and tailorable surface functionalities. The size, structure, and functional groups of nanocelluloses are dependent on the source of cellulosic fibres and preparation method [[3]].Other nanofillers, very recently discovered with large potential in water treatment applications are MXenes. MXenes are a new class of 2D metal carbides and carbonitrides, which are both conductive as well as hydrophilic [[4]]. MXenes have general formula Mn+1Xn, derived from MAX phases, where M is an early transition metal, A is an A-group element, mostly IIIA and IVA, or groups 13 and 14, and X is either carbon and/or nitrogen, by chemical etching in HF or NH4HF2 solutions, where n = 1, 2 or 3. The unique structure of MXenes offers combination of excellent mechanical properties, hydrophilic surface, transparency and metallic conductivity. Herein, we used electrospinning to prepared novel membranes based on copolyamide 6,10 reinforced by nanocellulose prepared from Qatari date palm waste and MXene 2D nanofillers which dramatically improved mechanical performance and separation efficiency of the membranes compared to neat copolyamide membranes. Prepared membranes were able to separate oil (vegetable and diesel) from water with efficiency over 96 % regarding of membrane composition and separation conditions. Additionally membranes exhibited good lifetime with maintaining high efficiency of separation. Acknowledgements This work was made possible by NPRP grant No.: 7-1724-3–438 from the Qatar National Research Fund (A Member of Qatar Foundation). The statements made herein are solely the responsibility of the authors. References [[1]] A.D.N. Nemerow, Industrial and Hazardous Waste Treatment, Van Nostrand Reinhold, New York, 1991. [[2]] G.-R. Xu, J.-N. Wang, C.-J. Li, Strategies for improving the performance of the polyamide thin film composite (PA-TFC) reverse osmosis (RO) membranes: Surface modifications and nanoparticles incorporations, Desalination 328 (2013) 83–100. [[3]] A.C.W. Leung, S. Hrapovic, E. Lam, Y. Liu, K.B Male, K.A. Mahmoud. Characteristics and Properties of Carboxylated Cellulose Nanocrystals Prepared from a Novel One-Step Procedure. Small 7(3) (2011) 302-5. [[4]] M. Naguib, M.W. Barsoum, Y. Gogotsi. 25th Anniversary Article: MXenes: A New Family of Two-Dimensional Materials. Advance Materials 26(7) (2014) 992 - 1005.Acknowledgements This work was made possible by NPRP grant No.: 7-1724-3–438 from the Qatar National Research Fund (A Member of Qatar Foundation). The statements made herein are solely the responsibility of the authors. References
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Effects of Drill Mud and Drive Torque Sinusoidal Excitation on Drillstrings Lateral and Torsional StickSlip Vibrations
More LessOil and gas drilling companies spend around 20$ billion annually from which 15% is attributed to material and productive time losses. The most prevalent drilling problems are caused by the Bottom-Hole-Assembly failure which includes drill string and drill bit damage or fatigue failure. During normal operation, to achieve penetration that cannot be met by the drilling motor power section, the bit torque generates an increased reactive torque that acts in the opposite direction of the driving rotation. This sudden increase in reactive torque is transmitted through the drill string as torsional ‘stick-slip’ vibration, which is often regarded as one of the most damaging modes of vibration. Due to cyclical rotation acceleration and deceleration of the bit, Bottom-Hole-Assembly, or drill string, this phenomenon produces accumulation and release of energy stored as several turns of twist in the rotor. While downhole vibrations are difficult to prevent and cannot be totally eradicated, implementing of corrective methods may be highly efficient for drilling optimization. In the present work, the effect of drill mud on drilling dynamics is studied, then, a sinusoidal excitation is added to the drive torque and resulting impact on downhole equipment is presented. A laboratory scale arrangement consisting of a flexible rotor and a stator is used, and attention is paid to whirling and stick-slip motions of the drill string. The results are provided in the form of responses in the time and frequency domains. A non-linear coupled dynamic model of a rotor enclosed within a stator and subjected to non- linear mud film force is developed. Comparisons with simulations data are also included. The work is one of the first studies carried out on the influence of adding a sinusoidal excitation to the driving torque with the use of drill mud on drill-string whirling motions in a laboratory environment.
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Efficient and fast separation of emulsified oil/water mixtures with a novel micro/nanofiber network membrane
By Zhaoyang LiuProduced water is one of the largest waste streams emanating from oil and gas industries. If inadequately treated, emulsified oil droplets contained in produced water will contaminate the environment and subsequently pose severe threat to human health. Removal of tiny emulsified oil droplets in produced water is very challenging. In this study, we demonstrated a new concept for constructing oil/water separating membranes with ultra-long titanate nanofibers (over 30 μm in length) / cellulose microfibers. An integrated network membrane was achieved with these ultra-long micro/nanofibers. This new membrane demonstrates good mechanical flexibility, which are critical for practical applications. This membrane shows high separation efficiency (99.9%) for oil/water emulsions with oil droplet size down to 3 μm, and at the same time has high water permeation flux (6.8 × 104 L m-2 h-1 bar-1) at low operation pressure. The high water flux is attributed to the interconnected porous structure throughout the whole membrane, while the nanoporous selective layer contributes to high oil separation. In addition, the low-cost materials and fabrication process for this membrane suggests its great potential for industrial scale-up.
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Edgefunctionalized graphene nanoplatelet towards energy storage application
Authors: Lagnamayee Mohapatra, Ahmed Sodiq, Fathima Fasmin, Belabbes A Merzougui and Rachid ZaffouWith the increased demand in energy resources, great efforts have been keen to develop advanced energy storage systems. A redox flow battery is a type of rechargeable battery where rechargablity provided by two chemical components dissolved in liquids and separated by a membrane. Energy is stored in the liquid electrolyte in external tanks, rather than in the battery cell. Flow batteries are technically similar to fuel cells are targeted at large-scale energy storage solutions. [1] Graphene based materials have attracted great attention for used as an alternative electrode materials for electrochemical energy storage system due to its unique properties of large surface area, chemical stability, super mechanical flexibility, high electric and thermal conductivities and an atomic thick two-dimensional sp2 hybridized carbon network. [2]To realize commercial use of graphene-based energy devices, it is highly desired to produce high-quality graphene at a low cost and large scale. Functionalization of graphene can further enhance its properties for efficient energy conversion and storage. Several innovative methods have been reported recently for functionalization of graphene, including mechanical exfoliation, surface polymerization vapor deposition (CVD), chemical exfoliation of graphite, sonication/intercalation,but these suffer from high manufacturing costs and technical difficulties.[3] Chemical doping of graphene with heteroatoms (e.g. Nitrogen) is one of the most feasible approaches to modulate its electronic properties. Traditionally, these methods often requires complicated processes and/or chemical reagents containing additional undesirable components in their structures. On the particular interest, mechanochemical ball milling process is a simple but efficient approach for producing edge-functionalized graphene nanoplatelets in large quantity and low cost. Previously, N-doped graphene materials generated by ball milling of graphite with N-containing gases like N2 and NH3 have been showed good electro catalytic activities for oxygen reduction reaction (ORR). [4,5,6] But,the amount of Nirogen doping is not sufficient in the above case. Therefore, we prepared N-doped graphene (N-GNP) by ball milling of graphene nanoplatelet (GNP) with melamine, which is nitrogen-rich solid organic compound and followed by pyrolysis. Both the temperature as well as the mass ratio between GNP and melamine affect the nitrogen content. In the ball milling process, the strong shear forces generated between high-speed rotating balls caused the mechanochemical cracking of the graphitic C– C bonds and spontaneous incorporation of Nitrogen from melamine at the broken edges of graphitic frameworks as well as the consequent exfoliation of graphene nanoplatelet. From the XRD, the (N-GNP) has peak broadening, indicates the occurrence of the ball-milling-induced edge doping of GNP. The XPS plot reveals the presence of three different nitrogen species in the (N-GNP), namely pyridinic, pyrolic and quaternary Nitrogen. The as fabricated materials used as a slurry electrode and their performances were investigated for VO2+/VO2+ redox couple for vanadium redox flow battery (VRB). The cyclic voltammetry (CV) results revealed that the Nitrogen functionalization of Graphene noplatelet allowed remarkable improvements in terms of both the reversibility and the current density than as received GNP. Electrical impedance spectroscopy (EIS) was used to further investigate that N-GNP is showing highest conductivity than GNP. Enhanced performance of N-GNP in terms of electrochemical activity and kinetic reversibility is owing to its electrical conductivity, surface area, graphitized surface and chemical stability of the electrodes affects the overall battery efficiency. References 1. P. Leung a, A.A. Shah, L. Sanz, C. Flox, J.R. Morante, Q. Xu, M.R. Mohamed,C. Ponce de Leon, F.C. Walsh, Journal of Power Sources, 360,2017, 243-283.2. H.-M. Tsai, S.-Y Yang, C.-C. M. Ma, X.F. Xie, Electro analysis, 2011, 23, 9, 2139 – 2143.3. RoshniYadav, C.K.Dixit, Journal of Science: Advanced Materials and Devices,2017, 2141-149.4. H. Wang, T. Maiyalagan, X.Wang, ACS Catal. 2012, 2, 781 − 794.5. W. Shi, K.-Hsu Wu, J. Xu, Q. Zhang, B.Zhang,D. S. Su, Chemistry of Materials, 2017, 29, 8670-8678.6. L. Dai, Y. Xue, L.Qu, H.-J. Cho, J.-B. Baek, Chem. Rev., 2015, 115, pp 4823–4892.
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Epibenthic assemblages on vertical artificial substrates: recruitment and succession patterns in offshore Qatari waters
Artificial structures get introduced into the marine environment by accident (e.g., shipwrecks) or intentionally, for logistical (i.e., coastal protection), industrial (i.e., oil exploitation) or biological habitat enhancement (i.e., artificial reefs). Similarly to other types of man-made submerged structures, offshore oil and gas platforms provide adequate hard substratum for the development of sessile marine invertebrates and to increase habitat and food availability for fishes and other motile marine organisms (Svane and Petersen, 2001). Furthermore, offshore platforms generally face minimum external interference and are usually located in waters with strong currents, which facilitate larval dispersal and settlement. Despite the fact that there are currently more than 800 offshore oil and gas platforms in the Arabian Gulf (Sheppard et al., 2012), scarce information exists about the biological assemblages associated to these structures (Burt et al., 2012; Stachowitsch et al., 2002). In fact, oil and gas platforms are high-security areas with an exclusion zone of at least 500 m around the structures (Kashubsky and Morrison, 2013), which prevents fishing and other human impacts, but also restricts sampling for scientific purposes. Considering the substantial habitat and diversity losses of natural reefs in recent years, the perceived ecological role of these offshore structures is gaining increasing recognition. Several research and industrial programs have tried to promote the transition of decommissioned platforms into artificial reefs (e.g., Rigs to Reefs, Reggio Jr, 1987). It is vital, therefore, to study the community structure in such isolated marine habitats, to assess their structural and functional similarity and connectivity to natural marine ecosystems (Zintzen et al., 2008), in order to provide the scientific underpinning to the planning and decommissioning stage of the platforms. These issues are currently being addressed in the framework of the project “Connectivity, diversity and genetic flow between offshore natural coral reefs and oil platforms - NPRP No.: 7-1129-1-201”. In this specific study we aim to understand the recruitment and succession patterns of fouling communities offshore in Qatari waters, using stainless steel plates as artificial substrates, in order to mimic the stainless steel jackets, which generally support offshore oil platform in the Gulf. In October 2016, six vertical structures were deployed in the northeast of the Qatari Exclusive Economic Zone, in an area between the Al Shaheen oil field and natural offshore reefs, to investigate the source of the epibenthic species that colonize these artificial substrates. Each structure supports 30 stainless steel fouling plates (20 × 20 cm), spaced by 1 m, at depths ranging between 10 m and 45 m. Temperature data loggers (Onset TidbiT) were attached to the plate structures, at max and min depth, to investigate how the temperature and depth variations affect recruitment and development of fouling assemblages. All the structures were successfully retrieved during the first assessment, done 15 weeks after deployment, in February 2017. After all the plates were photographed and data downloaded from the temperature loggers, the structures were re-deployed in the same location. This imagery is currently being analyzed using the online platform CoralNet, to assess the percentage cover, abundance and diversity of the fouling assemblages. Preliminary results of this first assessment indicate strong invertebrate recruitment, with almost 100% cover of the plates, at all depths and locations. A clear vertical gradient was, however, apparent, with diversity and cover generally increasing with depth. Barnacles, bivalves, anemones and fenestrate bryozoans were dominant at shallow depths, while other types of macroinvertebrates, such as encrusting sponges, foliaceous bryozoans and hydrozoans, became more dominant as depth increased. As expected, important seasonal variations of seawater temperature (e.g summer-winter) were registered in shallow (< 10 m) and deep (> 40 m) layers. Variations observed in deep water (>40 m) during autumn and early winter were, however, larger than expected. High variability was found in all locations, with sea temperatures ranging 3-4°C during one single day. The semi-diurnal and lunar periodicity of these variations strongly suggests they are associated with tidal cycles. The full seasonal time series (one year), which will be available in November 2017, will allow the precise delimitation of the periodicity and magnitude of these temperature variations. The final data analyses will integrate data on temperature with depth and distance among structures to infer on recruitment and succession of sessile and mobile epifauna. References Burt, J.A., Bartholomew, A., Feary, D.A., 2012. Man-Made Structures as Artificial Reefs in the Gulf, in: Riegl, B.M., Purkis, S.J. (Eds.), Coral Reefs of the Gulf, Coral Reefs of the World. Springer Netherlands, pp. 171–186.Kashubsky, M., Morrison, A., 2013. Security of offshore oil and gas facilities: exclusion zones and ships’ routeing. Aust. J. Marit. Ocean Aff. 5, 1–10. doi:10.1080/18366503.2013.10815725Reggio Jr, V.C., 1987. Rigs-to-reefs. Fisheries 12, 2–7.Sheppard, C., Al-Husiani, M., Al-Jamali, F., Al-Yamani, F., Baldwin, R., Bishop, J., Benzoni, F., Dutrieux, E., Dulvy, N.K., Durvasula, S.R.V., Jones, D.A., Loughland, R., Medio, D., Nithyanandan, M., Pilling, G.M., Polikarpov, I., Price, A.R.G., Purkis, S.J., Riegl, B.M., Saburova, M., Samimi-Namin, K., Taylor, O., Wilson, S., Zainal, K., 2012. Environmental Concerns for the Future of Gulf Coral Reefs, in: Riegl, B.M., Purkis, S.J. (Eds.), Coral Reefs of the Gulf, Coral Reefs of the World. Springer Netherlands, pp. 349–373.Stachowitsch, M., Kikinger, R., Herler, J., Zolda, P., Geutebrück, E., 2002. Offshore oil platforms and fouling communities in the southern Arabian Gulf (Abu Dhabi). Mar. Pollut. Bull. 44, 853–860. doi:10.1016/S0025-326X(02)00085-1Svane, I., Petersen, J.K., 2001. On the Problems of Epibioses, Fouling and Artificial Reefs, a Review. Mar. Ecol. 22, 169–188. doi:10.1046/j.1439-0485.2001.01729.xZintzen, V., Norro, A., Massin, C., Mallefet, J., 2008. Spatial variability of epifaunal communities from artificial habitat: Shipwrecks in the Southern Bight of the North Sea. Estuar. Coast. Shelf Sci. 76, 327–344. doi:10.1016/j.ecss.2007.07.012
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A Systematic Approach for Designing Sustainable Industrial WaterEnergy Integration Network
Authors: Jamileh Fouladi and Patrick LinkeNatural resources face growing demands and constraints in many regions as a result of economic, population growth and climate change. Due to those changes, it is extremely essential to invest towards water and energy nexus integration technologies since integrated thinking and actions can led to achieving a sustainable development and global supply of water and energy. The water-energy nexus and integration has been recently proposed to minimize water-energy footprint of an industrial park. It is required to develop a systematic approach for water-energy nexus network and interconnections among the processes. Previous research works mainly have presented the general superstructure and approach to develop economically optimal water networks that achieve a specified footprint target. In this work, one of the previous approach for water network has been extended with cooling systems options in order to capture the linkages between water and energy within industrial cities. The objective of this paper is to develop a framework for optimizing energy and water resources from processes that have a surplus of energy at various qualities. A systematic procedure is developed for optimizing and maximizing the benefits of these nexuses, considering power generation from a net surplus of waste heat energy from each plant by accounting for different sustainability metrics. The developed approach includes the use of composite curve analysis to first identify the potential for excess heat and then used to develop the combined water-energy network. A superstructure is generated to embed various configurations and related optimization formulation is solved to obtain an optimal process that economically satisfies the demand for water and energy considering some environmental metrics. Special emphasis is placed on capturing the synergy potentials from utilizing excess process heat and synergies across cooling and desalination systems, as well as synergies with the surroundings in terms of power and water exports from the industrial cluster. The work considers multiple objectives to explore trade-offs between minimum total annual cost and environmental sustainability metrics. A case study of an industrial cluster of typical processes operating in Qatar is presented to highlight the benefits of integration. It is shown how economically very attractive solutions across the nexus are identified by the proposed optimization-based approach. The results indicate that by water-energy integration the footprint reduction can be significant while economically is attractive too. Therefore, there is a great potential for savings water-energy resources by water-energy integrations. The work is contributed to sustainable development such as less pollution and resource minimization.
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Determination of the levels of Particulate Matter 25 and 10 and their elemental Composition in Qatar
Authors: Ahmad Ali Ahmadi, Perumal Balakrishnan, Konstantinos Kakosimos and Ipek GoktepeParticulate matter (PM) pollution is one of the major environmental pollution issues severely affecting human health and air quality all over the world. Based on the recent World Health Organization (WHO) report, PM levels were considered relatively high in Qatar. This might mainly be attributed to arid climate, but also due to rapid industrialization and urbanization as well as traffic. The literature on PM pollution and its source is limited in Qatar and the region. Therefore, this study was carried out to assess the air quality at different locations in Qatar, identify the levels of PM2.5 and PM10, and determine the elemental composition of PM2.5 and PM10 to trace their sources. A total of 100 samples (60 for PM2.5 and 40 for PM10) were collected using SKC Deployable Particulate Sampler (DPS) System for 24-hr during the months of September 2016 to December 2016. The sampling was conducted at five different locations, namely, Qatar University (QU), Education City (EC), Al Waab street area (AD), Whole Sale Market area (WM), and Al-Wakrah City (AW). The elemental composition of PM samples was determined using an inductively coupled plasma optical emission spectrometry (ICP-OES). The relationship between the environmental conditions and PM levels were also established. The health risks associated with different PM levels was calculated using the US EPA Air Quality Index (AQI) tool. The overall mean concentrations of 24-hr PM2.5 ranged from 49.88 μg/m3 to 64.28 μg/m3, while PM10 levels were between 126.69 μg/m3 and 184.55 μg/m3. The four months mean concentrations of PM2.5 were determined to be 49.88, 64.28, 55.47, 58.84, and 56.52 μg/m3 at Qatar University, Education City, Al Waab, WSM, Al Wakrah city, respectively. The average 24-hr PM10 levels were 138.24 μg/m3 at QU, 156.44 μg/m3 at EC, 126.69 μg/m3 at AWb, 184.55 μg/m3 at WM, and 160.24 μg/m3 at AW. The concentrations of PM2.5 detected at each station exceeded the WHO guideline (20 μg/m3) by 2.5 to 3 fold during the study period. The presence of high concentrations of Ca, Fe, Al, Fe, Sr, Mn, Na, and Mg indicated the major sources of PM to be soil/crustal. The identification of Ni, Co, Cr, Cd, Ba, Pb, V, and Zn were directly related to anthropogenic sources, specifically due to fossil fuel combustion and vehicular emission and these levels were reported at the highest levels at the wholesale market station. The AQI levels reported at all stations indicated that overall air quality at Qatar University and Al Waab street area was considered to be Moderate for PM10 and Unhealthy for sensitive group for PM2.5 levels. While in Education City, Whole Sale Market, and Al-Wakrah city areas had unhealthy and unhealthy for sensitive group ratings for PM2.5 and PM10 levels, respectively. The statistical analysis on determining the effect of meteorological factors (temperature, humidity, and wind speed) on the concentrations of PM2.5 and PM10 showed that there is a significant relationship (P?0.05) between wind speed and temperature and PM levels at all stations. These findings highlight the need for more research on PM pollution 1) to determine seasonal levels since this study only covered four months (September-December), 2) to better understand the source of PM pollution (in addition to elements, the levels of Poly Aromatic Hydrocarbons should also be determined), and 3) to establish more effective control measures to protect public health and preserve the environment in Qatar.
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Distribution of the Endangered Haloxylon persicum Bunge ex Boiss &Buhse Ghada and conservation for food security In Qatar
More LessHaloxylon persicum Bunge ex Boiss &Buhse native and rare plant in the state of Qatar known as Ghada, Qadha, Rimth, it's endangered, high palatable species, a favored plant to stabilize sand dunes, conserve water and soil, prevent soil desertification, and improve environmental conditions. It's small tree or shrub to 3 m, trunk 10- 25 cm in girth; stem richly branched, glabrous; young branches slender, green; leaves 0.5 – 1.25 mm, scale-like, acute, connate into a cup, with a tuft of short hairs in the axil; flowers on short spicate branchlets. It's evergreen plant blooms at the end of August and during September. The freshly harvest seeds recorded high germination percentage but it's rapidly lost viability The species distribution in the Middle East, the species is distributed mainly in the Sinai Peninsula, Egypt, and central and northwestern Saudi Arabia on the Arabian Peninsula, the plant distributed in deep, often drifting sand. Previous studded recorded it east of Salwa at sand dunes (the area now known as Al Mashbiya), near the Saudi Arabian border. Haloxylon persicum used for grazed by camels; highly valued as firewood by Bedouin and desert villagers. Through years 2012 to 2017, the Genetic Resources Department, Department of Agricultural Research, Ministry of Municipality and Environment in Qatar collected, surveyed and has some inventory activities for flora in Qatar. but they did not record any distribution of Haloxylon persicum only recorded in Al Mashbiya at Lareeq the state of Qatar is home to some unique and important habitats, Qatar has very limited number of trees and shrubs but due to changes in land use, including increased development, camel overgrazing, human activities, habitat reduction has emerged as a significant threat to the biodiversity of this country. In the last decade, there has been increasing effort to protect and conserve global biological diversity. Significant importance has been placed on new development being undertaken in a sustainable way and the restoration of landscapes damaged by past actions. These genetic relatives of crops also still remain largely uncollected and therefore they are largely unevaluated and unavailable for future breeding programs in agriculture and farming. The conservation of these genetic resources preserves the invaluable raw material needed to develop new varieties of crops in response to changing environments and climate. Qatar is firmly committed to conserving its biodiversity and is party to the Convention on Biological Diversity (CBD) and within this the Global Strategy for Plant Conservation (GSPC) and has developed its own National Biodiversity Strategy and Action Plan (NBSAP). Based on an assessment of the status of biodiversity in the country, Qatar's NBSAP identified a total of 11 strategic goals that identify the most pressing biodiversity issues in Qatar such as protected areas, agrobiodiversity and desertification, scientific research, education and public awareness, invasive alien species etc. To enable Qatar to address both the NBSAP and GSPC targets in relation to plant conservation effectively, fundamental baseline data needs to be obtained. Regional Red Lists following the IUCN Categories and Criteria are an invaluable tool to assess the risk of extinction to species within a country, informing national and regional conservation planning and directly addresses key objectives of both the GSPC and NBSAP. Many reports suggested the Haloxylon persicum Extinct in Qatar but the current study record the excellent site for distribution of Haloxylon persicum there are more than 50 individuals plant recorded using GPS points and satellites map. The distributions maps were prepared. The current research collected seeds, herbarium samples, and DNA samples and their conserved in Qatar gene bank and herbarium.
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Analysis of steam reforming of methane integrated with solar central receiver system
Authors: Haider Ali, Furqan Tahir, Maimoon Atif and Ahmer AB BalochSteam reforming is used for the production of hydrogen or other useful products from hydrocarbon fuels such as natural gas. Reforming is the process in which steam at high temperature reacts with the fossil fuel to form Syngas (CO+H2). The steam methane reformer is widely used in industry for the production of hydrogen. It has the advantage that the energy released from the combustion of hydrogen is almost four times as the energy released from the combustion of methane. In the present study, modeling and analysis of the steam methane reformer is carried out while utilizing the energy via solar tower. In the conventional modeling systems, solar based steam reforming is studied only for a single point in time and the dynamic fluctuations in the solar energy is not taken into account. Therefore, the performance metrics calculated are not necessarily representative of the actual performance of the solar reforming cycle since the performance will obviously be effected by the amount of solar input. In the work, herein, a solar steam reformer is modeled by considering the real-time data for Direct Normal Incident (DNI) irradiation for the city of Doha. As very high temperature is required for reforming, a solar central receiver tower is incorporated which can achieve high temperatures as much as 1300°C. The solar steam reformer is integrated into a solar receiver tower, surrounded by a field of heliostats, such that the solar is directly irradiating the solar reformer. The steam reformer and solar receiver tower is modeled and in-house code on Engineering Equation Solver (EES) software is written for performing the simulations. The system is analyze based on an annual performance so that the fluctuation of solar supply is taken into account with the cycle performance. The performance of steam methane reformer is studied for three representative days of the year that is 29th April, 15th May and 11th August. The performance characteristics of the steam methane reformer is analyzed in terms of methane conversion (Methane Conversion = (xCO+ xCO2)/(xCO+ xCO2+xCH4), where x is the molar concentration) and molar concentration, while incorporating the solar energy data. For 29th April, the peak incident energy is observed at around 1300 hours and the maximum methane conversion (Methane Conversion = 1) takes place at same time due to high solar irradiation. As for the molar concentration of different species, a maximum hydrogen presence in the peak solar irradiance, and the minimum amount of steam and methane is observed. CO presence tends to increase as well, at solar peak hours whereas the CO2 presence does not vary much and almost remains constant most of the time. Similar trends is observed for 15th May while as for 11th August due to no overcasting and continuous solar irradiance, a smooth trend of solar irradiance and consequently a smooth trend of methane conversion and molar concentrations is observed. The steam methane reformer with the solar receiver tower is effectively converting the methane during the solar hours of day. The study provides information about the performance characteristics of the steam methane reformer.
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Electrocatalytic properties of Pt nanoparticles grown on MXene surface
By Peter KasakElectrocatalytic properties of Pt nanoparticles grown on MXene surface Sifani Zavahira, Jaroslav Filipb, Khaled A. Mahmoudc, Jan Tkacd Peter Kasaka,* a Center for Advanced Materials, Qatar University, P.O. Box 2713 Doha, Qatar bDepartment of Environmental Protection Engineering, Faculty of Technology, Tomas Bata University in Zlin, Vavreckova 275, 76001 Zlín, Czech Republic c Qatar Environment and Energy Research Institute (QEERI), Hamad Bin Khalifa University (HBKU), P.O. Box 5825, Doha, Qatar d Slovak Academy of Sciences, Institute of Chemistry, Department of Glycobiotechnology, Dubravska cesta 9, Bratislava, SK-84538; It is well known that modification of nanoparticles (NPs) allow precise tailoring of their physical and/or chemical properties. MXenes (Ti3C2TX) are 2D nanomaterials with a unique layered structure, hence are frequently studied in energy transformation and storage applications, especially for supercapacitor development. Metal (Au, Ag, Pd, Pt, Co..) and metal oxide (Mn3O4) modified MXenes, have shown significant increase in their catalytic properties compared to the pristine material, while MXene specifically contributing to the stability of the overall material. In this regard, we hypothesised that using MXene as the support material for Pt NPs will enhance the electrocatalytic water splitting efficiency of Pt catalyst, and this will allow us to use a low weight percentage of the otherwise expensive Pt. Hydrogen generation from water splitting produces clean energy, but the high overpotential hinder the rate of hydrogen evolution reaction (HER). Pt being the most efficient catalyst studied to date that can lower the overpotential of this demanding reaction, it is important to find avenues to minimize the amount of Pt used. In this study two Pt NP on MXene were prepared according to two different synthetic protocols. In the first approach (in-situ) Pt NPs were reduced from a Pt salt solution, and this resulted in partial oxidation of MXene layer in the vicinity of Pt4+ ions. Secondly, two catalysts were synthesised with the aid of NaBH4, external reducing agent for structure and activity comparison reasons. Different times of reaction in combination with loading of 5 % and 25 % of Pt in feed were chosen to further investigate the influence of the preparation conditions on the final NPs. Characterization by XRD, SEM, EDX and XPS revealed substantial differences in structure and composition of Pt/MXene nanohybrids synthesised in-situ and with reducing agent. Pt NPs prepared by reducing agent stacked into clusters and the initial Ti3C2TX MXene remained relatively unchanged after the Pt NP synthesis. Whereas, without NaBH4 the Pt precursor was more intensely reduced by the initial MXene particles, this in turn changed MXene NP structure. It was found that this method provided a nanohybrid with a higher overall concentration of Pt and the observed Pt NPs were assembled into larger clusters. HER was tested using cyclic voltammetry performed in a deaerated 100 mM H2SO4 acid solution. Significant boost in the HER rate was observed after modification of MXene with Pt NPs compared to that of pristine MXene (about 1 mA cm-2) irrespective of the synthetic protocol. Maximum current densities up to 61.4 ± 1.7 and 61.9 ± 9.9 mA cm-2 was achieved. This significant increase in current generation was accompanied with a shift of reaction onset potential. Catalytic performance of Pt NPs was tremendously enhanced in the Pt/MXene nanohybrids, thus these nanohybrides become attractive as HER electrocatalyst. Acknowledgements This contribution was supported by Qatar University Grant QUUG-CAM-2017-1. This work was made possible by NPRP grant No.: 6 - 381 - 1 – 078 and 9 - 219 - 2 - 105 from the Qatar National Research Fund (A Member of The Qatar Foundation).The statements made herein are solely the responsibility of the authors.
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Production of biolubricant from renewable feedstocks from Qatar
Due to increase in environmental pollution and decline in petroleum reserves, there is an increase in the demands of developing alternative renewable bio-based products. Petroleum and lubricant manufacturing companies are searching for alternative renewable bio-based products since environmental protecting agencies, all over the world, are putting stringent environmental regulation in practice. Especially, there is a lot of ongoing research to find an alternative and renewable fuels and lubricants. One such alternative for mineral oil based lubricants are biolubricants as they have minimal impact on the environment and human health; furthermore, they have lesser toxicity, excellent lubricating properties, and a higher biodegradability index. Recent research is primarily focused on the synthesis of biolubricants from vegetable oils or animal fats either by chemically modifying the structure of oil or by blending of additives. The aim of this study was to develop biolubricants from renewable feedstocks, found in Qatar, by blending a viscosity modifier additive to meet the existing lubricant standard specifications. We selected 3 renewable feedstocks from Qatar: (i) Waste cooking oil, (ii) Jojoba seeds, and (iii) Waste date seeds. Unlike waste cooking oil and date seeds, jojoba oilseeds need to be collected from the plant. Jojoba plants can be irrigated with brackish water and can be grown in arid region. Oil-rich jojoba seed, therefore, can be considered as the base oil for biolubricants. Waste cooking oil was procured from a local restaurant in Doha, Qatar. Both the Jojoba seeds and the waste date seeds were collected from the Qatar University Biology farm in Zubarah. Initially, the seeds were sun-dried and grounded using a kitchen grinder. Next, oil from jojoba seeds and waste date seeds was extracted using a soxhlet extractor; hexane was used as extraction solvent. Soxhlet extractor was operated for 8 hrs to extract oil from jojoba seeds and waste date seeds. Oil yields from jojoba seeds and waste date seeds were found to be 55% and 10.2% (wt/wt basis) respectively. Waste cooking oil (WCO), jojoba oil (JO) and waste date seed oil (WDSO) were further blended with a viscosity modifier additive, i.e., ethylene vinyl acetate (EVA) in concentrations of 2%, 3% and 4% to formulate biolubricants from all three vegetable oil feedstocks. Addition of viscosity modifier-Ethylene vinyl acetate to WCO, jojoba oil and waste date seed oil increased the kinematic viscosities to maximum values for WCO from 70 mm2/s to 197 mm2/s at 30°C; similarly for jojoba oil it increased 27 mm2/s to 154 mm2/s at 30°C for Waste date seed oil it increased from 29 mm2/s to 160 mm2/s at 30°C. Viscosity for commercial oil (Mobil 20W40 Engine oil) was 190 mm2/s at 30°C. Viscosity index for all biolubricant formulations was calculated and it was found to be above 180. Thermogravimetric analysis of biolubricants revealed that formulated biolubricants were thermally more stable in order of WCO>DSO>JO>CO (Commercial oil). Biodegradability index was calculated BOD/COD ratio it was found to greater than 0.5. In this study, we found that biolubricants formulated from waste cooking oil, jojoba oil, waste date seed oil using viscosity modifier additive and all these biolubricants exhibited increased viscosity, higher viscosity index, better thermal stability and high biodegradability when compared with conventional mineral oil-based lubricant.
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تحسين كفاءة الطاقة للاجهزة المنزلية كثيفة الاستهلاك
More Lessنظرا لزيادة الاستثمارات و التطور الصناعي والتكنولوجي في عصرنا الحديث فقد ازداد الطلب على الطاقة الكهربائية لذا تقوم دول العالم سنويا بإنشاء العديد من محطات إنتاج الطاقة الكهربائية مما يؤدي بدوره الى زيادة الطلب على الوقود المستخدم لتشغيل محطات إنتاج الطاقة الكهربائية وهو ما يؤثر سلبا على صحة الأنسان والحيوان نتيجة انبعاث غاز ثاني اكسيد الكربون و الغازات الضارة الأخرى الملوثة البيئة والتي تعد أحد أكبر أسباب التغيرات المناخية والاحتباس الحراري. وتعتبر كفاءة الطاقة من أهم التحديات التقنية في عصرنا الحديث نظرًا لارتفاع تكاليف إنشاء محطات الطاقة الكهربية وانتاج الطاقة حتى تصل للمستهلك والذي يتحمل تكلفة انتاج الطاقة على عاتقه، لذا فقد اتجه العالم بأثره في البداية إلى استخدام مصادر الطاقة المتجددة و لكنها لم تلبي كمية الطلب المتنامي على الطاقة بالإضافة إلى ارتفاع تكاليف انتاج الطاقة من بعض المصادر المتجددة للطاقة مثل الطاقة الشمسية وطاقة الرياح وندرة أوعدم وجود مصادر الطاقة المتجددة في بعض البلا بالإضافة إلى أن مصادر الطاقة المتجددة لا تلبي إلا قدر بسيط من إحتياج الطاقة الكهربائية. وحديثا تم التوجه وبقوة إلى تحسين كفاءة الطاقة للأجهزة الكهربائية المنزلية كثيفة الاستهلاك والتي تستهلك قدر كبير من الطاقة يذهب جزء كبير منها هدرا بسبب عدم كفاءة هذه الأجهزة و عدم توفيرها للطاقة حيث تفقد حوالي ٩٠ % من الطاقة المستهلكة بواسطة لمبات التنجستين في صورة حرارة ولا يستفاد منها كضوء (الوظيفة الرئيسية للمبة) بل يتم المعاناة بعد ذلك من التخلص من تلك الحرارة عن طريق استهلاك قدر اكبر من الطاقة عن طريق المكيفات مما يتسبب في مضاعفة الاستهلاك. ومع التطور الكبير في أجهزة قياس الطاقة الكهربائية و ما مكنته من القدرة على جمع البيانات من الشبكة الكهربائية و قيمة الاستهلاك في جميع القطاعات سواء التجارية و الصناعية و المنزلية بل و تسجيل جميع العناصر المتعلقة بالاستهلاك للطاقة الكهربائية كالقيمة الفعلية للاستهلاك و معامل القدرة الكهربائية و الطاقة الغير فعالة و الحمال القصوى و فترات الذروة و القدرة على تحليل تلك البيانات بصورة سهلة جعلت من اليسير تحديد كيفية خفض الاستهلاك دون الحاجة انشاء محطات طاقة كهربائية جديدة أو صرف مبالغ كبيرة على صيانة المحطات الموجودة بالفعل. لذا فان البحث في تحسين كفاءة الطاقة للأجهزة المنزلية الكهربائية كثيفة الاستهلاك و انتاج أجهزة كهربائية منزلية و غير منزلية ذات كفاءة طاقة عالية قد يكون محور ارتكاز للعديد من العلماء و الباحثين و دعمت ذلك العديد من حكومات الدول المتقدمة لما له من مردود اقتصادي و بيئي حيث يوفر ملايين الدولارات سواء عن طريق خفض الانتاج و عدم الحاجة لبناء المزيد من محطات توليد الطاقة الكهربائية أو في علاج تأثيرات انبعاثات الغازات مثل غاز ثاني أكسيد الكربون وغيرها من الغازات الضارة و التي لها العديد من الأثار السلبية على البيئة وصحة الإنسان. يساهم الاستثمار في تحسين كفاءة الطاقة للأجهزة المنزلية في تحسين الأقتصاد عن طريق تشجيع الابتكار وخلق فرص عمل للبحث في مجال تحسين كفاءة الطاقة و الحفاظ على موارد الدول من الوقود كما تساهم في تعزيز استقلالية الدول, مما يسهم في الحفاظ على الطاقة إلى جانب تحقيق رضا المستهلكين من خلال توفير منتجات عالية الجودة و موفرة للطاقة و حماية البيئة من أضرار الانبعاثات الكربونية الضارة و تجنيب الحكومات إنشاء المزيد من محطات انتاج الطاقة الكهربائية التي تكلف مبالغ باهظة.
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