Qatar Foundation Annual Research Conference Proceedings Volume 2018 Issue 1

Concentrated photovoltaics (CPV) is advantageous as compared to a conventional non-concentrated photovoltaic (PV) system due to its ability to increase PV cell efficiency and replacing expensive PV material with an abundant and inexpensive reflective or refractive concentrator material. In this work, an overall solar to electrical and thermal conversion efficiencies between a concentrated photovoltaic system thermally regulated by a phase change material (CPVPCM) and a PV system is compared for Qatar climatic conditions. The electrical and thermal behavior of both, CPVPCM and PV, systems are simulated using an already developed and validated coupled electrical-thermal and optical model. A crystalline silicon PV cell is selected which has an electrical conversion efficiency of 14% and temperature dependent maximum power loss coefficient of -0.45% K-1 at standard test conditions. The width of the PV cell is 0.015 m for the CPVPCM system while a 6” ×  6” PV cell is considered for the conventional PV system. The same footprint of 1 m2 is selected as a physical equivalency criterion for both systems to compare their electrical and thermal output. Therefore, 36 PV cells, connected in series, represents footprint of 1 m2 for conventional PV system while the length and configuration of the PV cell for a CPVPCM system depend on the concentration ratio and type of concentrator to achieve equal footprint of 1 m2. The CPVPCM system uses a parabolic trough concentrator to focus sunlight onto a PV cell. The concentration ratios of 10 × , 15 ×  and 20 ×  are considered in this work, which results in lengths of 5.34 m, 3.56 m and 2.67 m to achieve 1 m2 footprint. An increase in incident irradiance density due to concentration instantaneously generates more power from a PV cell in any CPV system. However, it also increases the PV cell temperature and reduces power output because of the temperature dependent negative power coefficient of PV cells. The electrical power output loss due to temperature diminishes the gain in the electrical output due to the concentration of the irradiance. Furthermore, the elevated PV temperature also results in associated degradation mechanisms such as thermal aging, delamination, and mechanical damages. Therefore, cooling of a PV cell in a CPV system is essential to prevent the net power loss and gain the advantages of increased incident irradiance density. Four different commercially available solid-liquid phase change materials (PCM) are investigated for passive cooling of the CPVPCM system. The PCMs absorb and store excess heat during solid to liquid phase change and thereby, regulate the temperature of the PV cell. The heat storage by PCMs also leads to a potential utilization of thermal energy trapped within the PCM. The selection of a PCM depends on its several thermophysical properties such as melting temperature, latent heat of fusion, density, congruency, and stability. In this work, the selected PCMs are Lauric acid, RT42, S-series salt, and ClimSelTM C48 which are reported to have congruency and cyclic thermal stability as per manufacturers' data sheet. The PCMs have melting temperatures ranging from 41 oC to 54 oC and latent heat of fusion in the range of 178 kJkg-1 – 220 kJkg-1. The PCMs are encapsulated inside an aluminum container behind the PV cell. The aluminum container is made of 3 mm thick aluminum sheet having outer dimensions of 0.105 m ×  0.042 m and inner dimensions, to contain PCM, of 0.099 m ×  0.036 m. The lengths of the aluminum container are 2.67 m, 3.56 m and 5.34 m for concentration ratio of 20 × , 15 ×  and 10 ×  respectively. Two consecutive days of each month of a year are selected to simulate the optical, thermal and electrical behavior of both systems. The direct beam irradiance is obtained using the clear sky Bird's model while weather conditions such as ambient temperature and wind conditions are obtained from experimentally measured data from Qatar meteorological department. Since single axis tracking is a pre-requisite for parabolic trough concentrator; therefore, single axis tracking for PV system is considered as well to achieve equivalency regarding input conditions as well. The temperatures of the PV cells, IV curves to calculate maximum power point, the instantaneous power produced over a day using maximum power point tracking, total power produced over a day, and thermal energy storage in the PCMs are predicted by performing simulations of the electrical, thermal and optical behavior of both systems. It is found that the salt performs better than all other selected PCMs due to its high-energy storage density. The electrical output of the CPVPCM for concentration ratio of 10 ×  and 15 ×  is greater than the PV system and comparable at a concentration ratio of 20 × . However, the CPVPCM also store thermal energy, therefore, achieves higher overall solar to the electrical and thermal conversion efficiency as compared to the conventional PV system. Further studies are required, using experimentally measured irradiances instead of using a clear sky model, to investigate and compare the overall conversion efficiencies of the CPVPCM and conventional PV systems.

Redox Flow Batteries (RFBs), among other options, is uniquely suited for large-scale Electrical Energy Storage (EES) due to many advantages over the conventional sealed batteries (e.g., lead-acid and Li-ion batteries). Owing to its design flexibility, flow batteries can meet a wide range of commercial-scale EES applications with varying power-to-energy ratios. In addition, flow batteries have excellent energy efficiency and competitive life-cycle cost and are considered to be inherently safer compared to conventional sealed batteries. Despite its attractiveness and demonstrated performances, flow battery technology still suffers from high system capital cost (which limits its potential deployment into grid storage applications) and low energy density of the reactant fluids (which leads to large footprint and makes it impractical for EES applications with confined spaces). These challenges can be addressed if higher energy density and cheaper battery materials are developed. An attractive approach has been recently proposed, where the active materials are mixed with carbon to create a flowable electrode (otherwise known as slurry electrode). This system helps to operate flow battery with increased concentration of redox species and as a result the energy density is significantly improved.Slurry electrode (shown in Fig. 1) has been defined as “a suspension of particles with large double-layer capacity, such as activated carbon, in an electrolyte solution” [1]. These particles transfer charge from an electrochemical cell to an external reactor, where a substance is oxidized or reduced, and are recharged in the cell [1]. Unlike conventional RFB system, the semi-solid technique uses fluid electrodes that are electronically conductive [2]. Slurry electrodes are characteristically dynamic, particles continuously move and continuously make and break contact with one another. Percolation theory defines a critical loading, fc, above which there are enough particles in the slurry that, at any point in time, a constant network of particles is formed that spans the distance from one boundary to another [3]. It is due to these networks of percolated particles that slurries (with sudden increase in conductivity and viscosity at percolation) are able to conduct electrons out into the electrode and away from the current collector to utilize the high surface area of the particles for electrochemical processes [4, 5]. Other advantages of slurries involve their ability to have high surface areas, simple assembly and ease of maintenance through filtering (for example the carbon materials can be recycled without necessarily opening up the cell). The performance of slurry-electrode-based flow batteries highly depends on the features of the interaction between the particles and current collectors. Parameters such as storage duration or maximum power can be tuned by adjusting the properties of the slurry, being extremely important are the ionic and electrical conductivities of the slurries. Figure 1 In this presentation, the performance of slurry electrodes, based on carbon and redox systems (Vanadium/CNTs and Vanadium/Graphene), focusing in particular on electrochemical performance, conductivity, corrosion, and cell performance will be presented. We achieved high electrochemical activities in the case of Vanadium/CNTs as compared with Vanadium/Graphene as shown in Fig. 2. According to the structural features of the CNTs; the oxygen functional groups improve the hydrophilicity of the electrode. The O = C-OH groups on the CNTs probably behave as active sites, and facilitate the reactions of VO2+/VO2+ redox couple. Figure 2 References [1] B. Kastening, et al., «Design of a slurry electrode reactor system,» Journal of applied electrochemistry, vol. 27, pp. 147-152, 1997. [2] Z. Li, et al., «Aqueous semi-solid flow cell: demonstration and analysis,» Physical Chemistry Chemical Physics, vol. 15, pp. 15833-15839, 2013. [3] L. Gao, et al., «Effective thermal and electrical conductivity of carbon nanotube composites,» Chemical Physics Letters, vol. 434, pp. 297-300, 2007. [4] T. J. Petek, et al., «Characterizing Slurry Electrodes Using Electrochemical Impedance Spectroscopy,» Journal of The Electrochemical Society, vol. 163, pp. A5001-A5009, 2016. [5] H. Parant, et al., «Flowing suspensions of carbon black with high electronic conductivity for flow applications: Comparison between carbons black and exhibition of specific aggregation of carbon particles,» Carbon, vol. 119, pp. 10-20, 2017/08/01/ 2017. [6] H. Yoon, et al., «Pseudocapacitive slurry electrodes using redox-active quinone for high-performance flow capacitors: an atomic-level understanding of pore texture and capacitance enhancement,» Journal of Materials Chemistry A, vol. 3, pp. 23323-23332, 2015.

Urban air pollution is an inevitable consequence of the urbanization representing a growing concern to scientists, policymakers and an increasing fraction of the population. Air pollution is an acute problem especially in the developing countries, where the growing population, developing industry and improving life standards are generating environmental challenges. The State of Qatar has witnessed unprecedented rapid economic growth, and fast development and urbanization during the last few decades, accompanied as usual, by heavy construction and mega scale projects, resulted in adverse environmental effects. Air pollution represent one of these major effects and challenges. Direct exposure to volatile organic compounds VOCs implies public health concern. Even low concentrations of VOCs have been associated with damage to the central nervous system (CNS). The CNS is the primary target organ for toluene toxicity in both humans and animals for acute (short-term) and chronic (long-term) exposures (HMDB, 2014). Benzene is a known human carcinogen and is linked to an increased risk of developing lymphatic and hematopoietic cancers, acute myelogenous leukemia, as well as chronic lymphocytic leukemia (EPA, 2004). Information regarding ambient VOCs exposure is limited in Qatar and in the whole Gulf region in terms of values and types of compounds; however, it can be expected that the concentration values are elevated as they are regarding the other combustion related components such as CO, NOX, SO2 and black carbon (Qatar Environment Statistics Annual Report, 2014). The ozone concentration is also often exceeding the limit value due to the intensive photochemical processes induced by the strong sun radiation and the presence of ozone precursors. The main sources of the critical VOC pollutants in the atmosphere- Benzene, Toluene, Ethylbenzene, and Xylenes- referred to as BTEX, are the motor vehicle exhausts, emissions from the use of solvents, and emissions from the chemical and petroleum industries. This study was an attempt to assess and evaluate the impact of traffic and nearby industry on the air quality of Doha by studying the most important combustion related volatile organic compounds such as BTEX, and atmospheric trace gases (NO, NO2, O3 and NH3). The research aims have been accomplished by conducting two sampling campaigns across the area of Greater Doha with 14 different locations at the main access roads and remote areas during two weeks sample collection period; from February 29, 2016 to March 15, 2016; and from March 16, 2016 to March 31 2016, to quantify the ambient air levels of these pollutants. Passive absorption (diffusion) tubes were used in this campaign because of their mobility, applicability and affordability for outdoor air sampling, as they are easy to handle and require cheap and user-friendly equipment (Buczynska, 2009). Concentrations from most components indicated hot spots roads at the south more than the north of Doha in which BTEX ranged from 7.68-40.5 μg/m3, NO from 7.97-170.4 μg/m3, NO2 from 41.5-105.5 μg/m3 and NH3 was ranged from 8.87-30.4 μg/m3. On the other hand, ground level ozone (O3) depleted at the air pollution hotspots showing higher concentrations at the northern part of the city with a range from 12.1-70.9 μg/m3. Among the samples, the maximum NO2 level was lower than Qatari environmental executive law of 150 μg/m3 on average period of 24-hours. Also, the maximum benzene concentration was 3.15 μg/m3 less than the standard of 5 μg/m3 established by European Community (EC). Visualization of the results has been performed using demonstration hotspot multilayers maps, overlaid in Google-Earth, showing the geographical distribution of the concentration of each individual component. The anticipated continuation of this research will be accomplished by increasing the sampling points and conductive more extensive survey in order to get more representative data with higher spatial resolution. The resulted air quality maps will be essential tools in the hands of policy and decision makers, as a contribution to the current efforts to improve air quality in urban areas. The authors would like to thank Qatar National Research Fund (QNRF) for funding and supporting this project under the National Priorities Research Program (NPRP) award number NPRP 8-202-3-043. Refreneces: Buczynska, A. J. (2009). Atmospheric BTEX-concentrations in an area with intensive street traffic. Atmospheric Environment, 311–318. Committee on Tropospheric Ozone, N. R. (1991). Rethinking the Ozone Problem in Urban and Regional Air Pollution. Washington, D.C.: NATIONAL ACADEMY PRESS. EPA. (2004). EPA Air Toxics. Retrieved from https://www.epa.gov/sites/production/files/2016-09/documents/toluene.pdf HMDB. (2014). Human Metabolome Database. Retrieved from http://www.hmdb.ca/metabolites/HMDB0001505

The World Health Organization (WHO) attributes air pollution to 1 in 8 deaths worldwide, where exposure to indoor air pollutants is a significant contributor to incidences of heart disease, respiratory problems, and cancer (WHO, 2014). Since people spend the major part of the day indoors - especially in Qatar -, indoor air quality (IAQ) is a significant factor affecting their overall pollutant exposure via the respiratory-inhalation pathway. IAQ is mainly determined by the geographical location of a building, its proximity to outdoor pollutant sources such as industry, construction activities, traffic or natural pollutant sources (e.g. desert sand particulates), as well as the building characteristics itself (building envelope, air tightness, ventilation/air conditioning system). Indoor sources like decoration and furniture, as well as indoor activities like cleaning and cooking also affect IAQ. Recently, the WHO ranked Qatar second position worldwide of countries with the highest ambient PM2.5 exposure (WHO, 2014). The issue can therefore be regarded as of great significance to public health for the citizens of Qatar, and therefore warrants scientific study and potential mitigation of excessive PM2.5 exposure. In particular, the young citizens of Qatar are especially susceptible to the impacts of PM2.5 inhalation due to their early stage of physiological development. A building can function as a protective shelter for poor outdoor air quality, but without a dedicated IAQ enhancement strategy, buildings may not automatically lead to a reduced indoor exposure to air pollutants, including PM2.5, as well as other potentially harmful pollutants including: oxides of nitrogen and sulphur (NO2, SO2); ozone (O3), natural radiation (radon, Rn); microorganisms (bacteria and fungal spores); a range of volatile organic compounds, and hydrocarbons. This study aimed to characterise IAQ of Qatar's indoor environments, with a particular focus on schools and residences with consideration of outdoor air quality (OAQ) conditions. Simultaneous IAQ/OAQ measurements have been conducted using established reference methods and sampling techniques specifically developed for IAQ studies. PM10, PM2.5 and ultrafine particle concentrations, aerosol size distribution and particle elemental composition have been measured. Volatile organic compounds, aldehydes, NO2, SO2 and O3 were monitored. CO2, temperature and relative humidity were also monitored, and the air exchange rate between indoor and outdoor environments has been assessed. Semi-volatile organic compounds, such as polycyclic aromatic hydrocarbons, phthalates and flame retardants have been quantified in order to identify specific sources of contamination as derived from combustion and/or building material emission sources. Three school classrooms and associated school-pupil homes were selected for conducting IAQ assessments in order to determine pupil exposure levels to air pollutants over a 24-hour period. Volunteers were equipped with personal exposure monitors for determining their location and activity-dependent air pollutant exposure levels. The first measurement campaign of the research project was conducted in May, 2017. Three classrooms were monitored and five residences, as well as the outdoor location in the school's garden. The results indicate that the indoor concentrations of VOCs, aldehydes and PAHs exceeded the outdoor levels, and that pollutants concentration in residences were consistently higher than in the school classrooms. In terms of particulate matter (PM2.5) the opposite trend was observed. The indoor PM2.5 levels were far lower than the reference outdoor concentration. Regarding the comparison of school class rooms and homes, the same trend as in the case of VOCs was observed. Namely, the PM2.5 levels in homes were consistently higher than in the school classrooms. Overall, the results show that indoor environments represent a protective shelter against the outdoor particulate air pollution ion Qatar. The indoor air quality is determined mainly by pollution sources indoors – particularly in residences due to the presence of more intensive and versatile emission sources – including furniture, decorations, use of air refreshers; as well as activity generated emissions by the inhabitants like cooking, cleaning, or smoking. The second measurement campaign will be conducted in December 2017, when new data will be collected under different seasonal conditions i.e. mild temperatures, where buildings typically have more ventilation with the outdoor environment, and where higher ingress of outdoor air pollution may be expected. The authors would like to thank Qatar National Research Fund (QNRF) for funding and supporting this project under the National Priorities Research Program (NPRP) award number NPRP 8-202-3-043.

The worldwide continuous increasing of population provokes an increasing awareness about the food security. Qatar is one of the first countries establishing a Food Security Strategy Program to satisfy the demand of food and feed. Microalgae is considered as one of the most promising solution based on its ability to produce the essential elements needed for food and feed such as lipids, carbohydrates, proteins... In Qatar University, a diverse collection of Microalgae and Cyanobacteria strains isolated from different environments was established (QUCCCM). Microalgae, These photosynthetic microorganisms are capable of converting solar energy into useful compounds. Microalgae accumulate several kinds of metabolites such as proteins (6-52%), lipids (7-23%), carbohydrates (5-23%). In addition, microalgae produce have the ability to produce high-value metabolites. The aim of our work was to screen the QUCCCM and identify potential strains with high nutritional value for use as feed for poultry and livestock. In this study, Microalgal isolates belonging to 12 different species were investigated for their eligibility to be used as a feed. All strains were cultivated over a period of 10 to15 days depending on species. Optical Density and Dry weights were recorded every three days to follow the algal Growth. The results showed the presence of three categories of isolates (fast, medium and slow growing). Among them, the species Chlamydomonas sp. presented the highest growth rate (μ) with 0.89day − 1 ± 0.27 and a doubling time of 1.28/ day. Based on this result, the fast-growing strains were subjected to metabolite investigations in terms of lipids, proteins, carbohydrates, amino acids and Fatty acids to select the ideal strain(s) presenting high growth rate along with metabolites valuable for algae-based feed supplement. The highest protein and Lipid content was observed in the case of a freshwater strain belonging to the Mychonastes sp.with ∼ 50% w/w and 40.7% ± 0.015 respectively. Carbohydrates were seen highest in Chlorococcum sp.with a value of 30% ± 0.009%. Considering the marine strains, the isolates had a similar range of protein, Lipids and Carbohydrates content of (22%-34%), (32%-39%) and (8%-20%) respectively. Based on this study, one marine strain (Pichochloris sp.) having 33% ± 0.021 content of protein and 32.7% ± 0.036 as lipid, and one freshwater (Mychonastes sp.) holding the highest amount of metabolites were selected for deeply investigations in terms of FAME and Amino acid profiling which are crucial parameters that determine the feed quality. The results showed the presence of different essential Amino acids in the total protein fraction. Fatty acid profiling comprised saturated and unsaturated fats for all strains; most of them being rich with C18:0; C16:0 and C16:3. For the selected strains, the metabolite content during the growth period was followed by sampling every 3 days in order to identify the stage having high productivity and rich metabolite content. The analysis of the isolates showed an increase in the production of each metabolite during the growth, wherein lipids and protein amounts are relatively high while carbohydrates were comparatively low. These two selected strains will be improved in terms of lipid and protein production using media and salinity stress in order to enhance the production of essential nutrients such as omegas, amino acids and used for animal bioassay. In Conclusion, this study showed the existence of a diverse and rich collection of valuable strains with important metabolites that can support the country's food security program, by providing microalgae to supplement animal feed. Additionally, the potential candidates can be used for commercial applications.

Membrane Filtration technique is being accepted worldwide as an environment friendly and energy efficient technique in Desalination Industry as compared to Thermal Desalination techniques. However, the performance of membranes which include permeate flux and rejection is affected by the membrane fouling. The properties of membrane and surface features such as porous structure, hydrophilicity/hydrophobicity charge, polymer characteristics, surface roughness determine the fouling potential of the membrane. The hydrophilic and smooth membrane surface is usually considered desirable in tackling membrane fouling issues. Therefore, many studies have focused on to enhance surface characteristics of membranes by surface coating with polymers and nanomaterials. Since, membrane coating is not done during fabrication of the most commercially available membranes, therefore, it is also important to determine the surface features of the commercially available membranes to investigate their membrane fouling potential. Thus, the objectives of this study were (1) to perform membrane surface characterization of commercial Reverse Osmosis (RO) and Nanofiltration (NF) membranes using techniques such as SEM, AFM, FTIR and XPS; (2) to measure hydrophilicity/hydrophobicity of commercial RO and NF membranes through water contact angle measurement using sessile drop method and (3) to measure the flux and percentage rejection of NF and RO membranes using Dead end filtration technique. Here, the characterization of membrane surface in terms of surface roughness, using SEM and AFM, showed that the commercial RO membrane had more ridge and valley structures and higher average surface roughness i.e. 71.24 nm as compared to NF membranes (6.63 nm). In addition, water contact angle measurements showed that the NF membrane was more hydrophilic as compared to RO membrane. The average contact angle found for RO membrane was 59.94°. On the other hand, it was observed that NF membrane is extremely hydrophilic in nature. Due to which, contact angle value was not obtained for most of the runs. The droplet could diffuse in less than 5 seconds. In addition, the dead-end filtration experiments showed that the RO membrane had much lower flux as compared to NF membrane. This can be associated with the pore structure of these membranes. Since, the NF membrane has porous structure, in oppose to RO membrane, the flux of the NF membrane is usually higher than the RO membranes. As the membrane surface roughness and hydrophobicity makes it more susceptible to the fouling leading to reduction in membrane flux and performance, it can be concluded from this study that there is a need for surface coating of RO membrane with suitable nanomaterials such as graphene oxide to improve its hydrophilicity and surface smoothness. This will eventually make the membrane more resistant to membrane fouling and will establish the use of membrane filtration technique in desalination industry in Qatar in the future. Microorganisms have been isolated from Gulf sea water, identified and differentiated and are being used to study the biofouling of RO and NF membranes, that would be coated to limit the fouling problems. Acknowledgement: This research was made possible by NPRP grant # [9-318-1-064] from the Qatar National Research Fund (a member of Qatar Foundation). The findings achieved herein are solely the responsibility of the author[s].

Qatar focused on economic development since independence in 1971. The government has over the time established many developments oriented institutions and authorities, including the Supreme Planning Council, General Secretariat for Development Planning and Ministry of Development Planning and Statistics. Since the launch of QNV 2030 in 2008 with its four pillars (human development, social development, economic development and environmental development), this vision aimed to change the face of life in Qatar. Qatar is upgrading its speculation and development systems with indications of recuperation in worldwide markets in 2017. New patterns keep on emerging crosswise over esteem chain influencing supply, request and speculation situations in the nation. Both conventional players and new participants are reevaluating their arranged undertakings with updated estimates. As Qatar and worldwide markets move towards rebalancing, this article gives definite bits of knowledge into basic short and long haul factors set to shape the eventual fate of Qatar oil and gas markets. This work as a necessary manual for organizations wanting to extend and put resources into Qatar oil and gas advertises in close to medium term future. Openings and difficulties of growing new undertakings, evolving supply-request situations, development in developing markets, approach bolsters, new supplies and request sections, venture benchmarking are talked about in the exploration. For Qatar, gas costs are considerably more imperative than oil costs in light of the fact that the estimation of gas sends out surpass that of oil trades. The estimation of LNG sends out surpassed the estimation of all other hydrocarbon items in 2015, speaking to roughly 46% of aggregate ware trades. Around a fourth of Qatar»s fares of LNG is sold at spot conveyance costs, and the rest is sold as per contracts identified with oil costs (with a deferral of a half year). Concerning the dissemination of LNG sends out, in 2015, 66% were sent out to Asia, where higher costs win. Global LNG costs dropped amid the most recent a half year because of creation surplus in the area. Qatar has kept up its creation limit since 2011, however new fares from Australia and the Assembled States have started to develop. Since the vast majority of Australia»s fares goes to Asia and as Japan resumes operation of certain atomic plants, costs in Japan saw the best decay however are as yet the most noteworthy in the locale. Unrefined petroleum costs incorporating traditions charges in Japan diminished by 40.1% between November 1, 2015 and May 1, 2016. Costs related to the American Henry Center just diminished by 8.5% in a similar period. For the most part, in the US, where most gas is sold at spot costs, bring down costs win, while Japan has the most astounding costs since gas is sold by method for long haul fates related to rough costs including custom expenses. Given the abundance in delivery limit and the expected wealth in LNG supplies, Qatar is creating and restoring its showcasing strategy with a specific end goal to ensure it offers in the market, particularly supporting long haul supply assentions for LNG trades. Because of the lower allure of LNG costs and its foreseen opulence, the World Monetary Standpoint report issued by the IMF in April, 2016, tempered its desires at gaseous petrol normal costs in 2016 (the weighted normal cost in the Japanese, American and European markets), by 10.8% against a similar report»s estimate in October 2015. It is additionally conjectured value steadiness on an extensive scale in 2017 and 2018. Economy in Qatar is relied upon to stay versatile in 2017, regardless of a frustrating Gross domestic product development of 2.7% in the primary quarter (QoQ), after a 4.1% development in the last quarter of 2016. Swelling should level off in 2017. Be that as it may, costs are diminishing for lodging, amusement and eateries, which could cultivate utilization. In any case, the presentation of a uniform 5% VAT rate over all GCC nations, endorsed on May, third 2017, is relied upon to build costs subsequent to being actualized in 2018. The oil and gas segments, experiencing the fall in vitality costs, were working in the red in 2016, however they should help bolster development in 2017 with the begin of creation at the Barzan office (increment fluid gas generation by 21%). The non-oil and gas parts were dynamic in 2016, and they will keep on being, driven by development (+11.7% QoQ in the main quarter of 2017) and the administrations divisions. Development segment stays one of the main recipients of the Qatari government»s speculation arrangement for the FIFA World Container 2022. In spite of the fact that a ban has been forced on new undertakings, officially planned speculations are significant and assessed at what might as well be called nearly USD 180 billion. The administrations area (money related administrations, property and broadcast communications) should see solid development in 2017. Qatar is right now experiencing gigantic change under the rubric of the 2030 National Vision, which intends to build up a propelled, learning based, and enhanced economy, no longer dependent on the hydrocarbon area. The administration is intensely associated with Qatar»s economy, in spite of the fact that it firmly energizes private interest in numerous areas. Interests in different parts including medicinal services, instruction, tourism and money related administrations, among others,. The principle monetary boosts in Qatar are oil, gas, and related enterprises, specifically the advancement of the North Field, the biggest non-related gaseous petrol field on the planet. Qatar»s condensed flammable gas (LNG) industry has pulled in several billions of dollars in remote speculation and made Qatar the world»s biggest exporter of LNG are relied upon to offer more prominent open doors for outside venture. Qatar»s LNG conveyance cost is about $5.20/mBtu, which is near the Russian pipeline gas breakeven cost, yet $2 to $3 underneath full-cycle cost for US LNG at the present Henry Center point costs of about $3/mBtu. This implies at current costs, US LNG makers could take care of their peripheral expenses yet not long haul breakeven costs. «With its great reputation of LNG venture execution and the co-creation of condensate and LPG from the North Field, Qatar is the most minimal cost LNG maker on the planet. As of now, the seven parts concentrating on those are anticipated to have a general positive effect on the social and financial way of life in Qatar. These areas are horticulture, training, medicinal services, mechanical improvement, domesticated animals, fishery, and tourism.

Degrading effect of energy generation from fossil fuel are extensively discussed and debated leading to paradigm shift to renewable energy generation. Energy generation from PV panels is the best alternative for state of Qatar which gets abundant sunlight throughout the year. Development of energy generation from PV panels helps in achieving the notion of “Energy Security”. Energy security refers to availability of reliable, cheap and quality power for consumption from customer point of view. Development in power electronics helps in achieving this idea by developing and operating converters circuits with good efficiency, efficacy, reliable, robust and free from maintenance. Encouraging the nurture and development of local energy suppliers will help in minimizing the cost of installation and maintenance. Including these economic constraints in the design of converters has become a crucial factor in developing industry oriented products through academic research. Suitability of several power converters for synchronizing the power generated from PV panels to utility grid. Recently developed Impedance source based converters are highly suitable for synchronizing the power generated from renewable energy to the utility grid. They eliminate the need for extra dc-dc converter by boosting the input voltage supplied from PV panels. Impedance source based converters are categorized as: Z Source Inverter and quasi Z Source Inverter (qZSI). qZSI is preferred due to its higher performance and continuous input current. Several methods are discussed in the literature to achieve boosting of input voltage. Inverter control requires modification in conventional Sine-Triangle compared based PWM. Operation of qZSI at different MPPT algorithms is also discussed. Cascaded qZSI operation to achieve higher power rating are also discussed. Implementation of advanced control techniques such as Model predictive control is also presented. Energy efficient qZSI achieved through different methods are also discussed. This paper presents novel control algorithm for control of qZSI as Front-End Converter (FEC) during non-sunshine hours. During sunshine hours, qZSI is controlled to inject active and reactive power into the grid. In absence of sunlight, qZSI can be operated as FEC to control reactive power management with the utility grid. To validate the proposed control algorithm, simulation results are presented for grid-connected qZSI powered from solar panel as shown in Fig. 1. Simulation results are formulated into following three sections: (a) Control of qZSI for active and reactive power management, (b) Transient response for qZSI to FEC transition and (c) Control of FEC for reactive power management.Control Algorithm: Control algorithm must satisfy the following requirements: a) When controlled as qZSI, i) Boosting of input voltage must be controlled to achieve the desired output rms voltage ii) Current injected into the grid can be at any power factor – unity, lagging or leading. b) Smooth transition from qZSI to FEC. c) When operated as FEC, i) DC Bus Voltage must be maintained constant and ii) Controlled reactive power management must be achieved. Proposed control algorithm is as shown in Fig. 2. It consists of two types of control blocks. Control blocks which are specific to a type of control algorithm and other which are common for both. Converter reference voltage generation and conventional Sine – Triangle comparison is common to control algorithms of both the inverters. For control of the inverter as qZSI, condition of Vin>Vth must be satisfied which means voltage generated from PV panels is sufficient for grid synchronization. During this mode, S1 and S3 are closed and S2 is opened. qZSI control consists of grid current control and dc bus voltage (Vdc) control. Active and reactive power demand is converted to current proportional and passed through PI controller to generate the converter voltage reference. DC Bus voltage controller gives the shoot-through duty cycle (D). Based on the value of D, shoot-through pulses are ORed with conventional pulses generated by sine-triangle comparison. When Vin>Vth is not satisfied, then the position of relays is changed. S1 and S3 are opened and S2 is closed. Due to this, the solar panel is disconnected from the inverter. The dc bus formed due to series connection of C1 and C2 must be controlled from the grid voltage. The dedicated control block shown in Fig. 2 for FEC generates the active current reference and add it up with required reactive current reference to give the grid current reference. This is passed through PI Controller to give the converter voltage reference. Conventional Sine-triangle comparison is performed to generate switching pulses.SIMULATION RESULTS To verify the control algorithm, the simulation results are shown in Fig. 3. Up to t = 2 sec, the inverter is operated as qZSI injecting controlled active power into the grid. At t = 2 sec, the relays are operated disconnecting the solar panel at the input and now inverter is controlled as FEC. Due to this, the dc bus voltage shoots up which is controlled with the control algorithm. To maintain the dc bus voltage, active current is drawn from the grid. Active current drawn is negligible compared to reactive power managed with the utility grid. Figure 3(a) shows the response of dc bus tracking during the operation. In qZSI mode, active power injection is controlled as shown in Fig. 3(b) and Fig. 3(c). When the inverter is controlled as FEC, reactive power absorbed and supplied are shown in Fig. 3(d) and Fig. 3(e) respectively.

Sustainability is one of the major challenges faced by the industrial sector as it is driven by both environmental and economic factors. Energy demands are increasing and, to date, most of the supply is generated via fossil-fuel combustion, such as coal, gas or oil. However, these processes release greenhouse gases, mainly CO2, that contribute to global warming and other environmental issues. Of the three fossil fuels, for a given amount of energy released, natural gas produces the least amount of CO2, making it the most vital energy source. The most practical way of transporting this natural gas over long distances is via liquefaction. However liquefied natural gas (LNG) plants consume substantial amounts of energy; thus, releasing significant amount of CO2. Therefore, enhancing the efficiencies of LNG plants is essential especially for large producer such as Qatar. As of today, Qatar is the largest producer of LNG in the world, with a capacity of near 78 Million tons per annual (MTA). Since the LNG industry in Qatar is a major contributor to the country's economy and development, there is a continuous need to improve and optimize existing LNG systems to extract more value out of them. Optimization of such complex system is; however, not a straight forward technique requiring different expertise ranging from engineering/process oriented insights to mathematical and thermodynamics techniques. Thus, it is deemed essential to identify plant sections that must be given priorities for optimization. This requires quantifying losses and efficiencies and one of the effective tools is exergy analysis. Identifying the areas of exergy losses within LNG plants emphasizes the areas where optimization is necessary. This project aims to foster the transition to cleaner LNG plants that operate more efficiently, in terms of energy consumption, towards an active contribution to the protection of the environment. The primary focus of the study is to identify exergy losses across a baseload LNG plant producing more than 3 MTA of LNG. In this research, a rigorous and detailed exergy analysis was performed on an entire actual LNG process that was simulated using ProMax® and Aspen Plus® simulation software. In order to carry out the thermodynamic analysis, exergy loss across each component of the entire plant was determined. Exergy analysis was not limited to process units, as it was extended to quantify exergy loss across the utility section. Results revealed that the main contributors to the exergy loss are the utility section, accounting for 49% of the total exergy loss. Within the LNG process, significant amounts of losses were found to occur in the liquefaction, sweetening and sulfur recovery units; corresponding for 37%, 30% and 21% of the total exergy loss, respectively. Components responsible for the highest exergy consumption were also highlighted, with the main consumers being the compressors and their drivers, stream generators, LNG flashing and storage, columns (absorbers, distillations) and heat exchangers. The contribution to the total exergy loss provided some insight on locations where improvements are needed to translate into more environmental and energy benefits. For example, most of the losses within the liquefaction section was attributed to compressors and the drivers responsible for the generation of the required shaft work; almost 19 MW exergy loss in the gas turbine corresponds to 1 MW exergy loss in the associated compressor. Thus, significant energy savings can be achieved via minimizing the compression energy. *Corresponding author. +974 44034148 Eamil address: [email protected] (E. Al-musleh) References [1] «2016 World LNG Report - International Gas Union,» Chevron, USA2016, Available: www.igu.org/download/file/fid/2123.

Direct methanol fuel cell has attracted worldwide attention as a promising alternative clean energy source due to growing environmental problems. A number of scientific groups are working to develop the fuel cells and make it a viable clean energy option. For fuel cells to be a feasible and economic viable innovation in the materials development, such as new electrocatalyst and polymer electrolyte membranes are required. Significant advancements in materials developments are required for fuel cells to be feasible for a wide range of portable, automotive and stationary applications. For DMFC, there are some challenges that need to be addressed before this technology become competitive, for example- slow kinetics of methanol oxidation, high methanol permeation resulting drop in fuel cell performance and the high cost of the catalyst. In the present work we focus on the electrocatalyst materials development for methanol electro-oxidation on the anode surface of DMFC. Platinum (Pt) and/or copper (Cu) based multi composition low cost electro-catalyst have been synthesized and characterized by impregnating onto the carbon nano-tubes (CNT) composites. These nanocomposite electrocatalyst materials have been characterized for their morphology by scanning electron microscopy (SEM), structure by X-Ray Diffraction (XRD), element mapping and other chemical and thermal properties by Fourier Transform Infrared Spectroscopy (FTIR), thermogravimetric analysis (TGA), and X-ray Photoelectron Spectroscopy (XPS). The results of the characterization confirmed successful formation of the desired electrocatalyst material. The electrochemical activity of these electro-catalysts for methanol electro-oxidation have been studied by cyclic voltametry (CV) and chronoamperometery (CA) at various concentrations of methanol and current density. The characterization and electrochemical activity tests showed good performance for the electro-oxidation of methanol for DMFCs. The present study opened up new avenues for developing lower cost Pt-based catalysts with better performance. These nanomaterials have potential to be used as electrocatalyst for DMFC applications. Keywords: Electrocatalyst, nanocomposite;direct methanol fuel cells, electro-oxidation. Acknowledgements: This publication was supported by Qatar university Internal Grant No. QUUG-CAM-15\16-2. The findings achieved herein are solely the responsibility of the author[s].

The constant increase in energy demand necessitates exploration of new oil fields at challenging reservoir environments. A proper selection of the drilling fluid, or a drilling mud, is crucial in minimizing the cost and time required for the drilling process. The circulating drilling fluid aids in cooling, lubricating the drilling bit and in removing the rock cuttings from the drilling well. Water-based muds are widely used as a drilling fluid in oil and gas industry while exploring the hydrocarbon. During deep-sea drilling activities at extreme depths, high-temperature and high-pressure (HTHP) conditions are encountered. These results in overheating of drilling equipment and malfunction due to lost circulation posing a severe limitation to the drilling fluid used. Several studies have been conducted to enhance the rheological and thermal properties of water-based drilling muds. Owing to the enhanced thermo-physical properties and stable nature, suspensions of nanoparticles have been suggested to be used along with drilling fluids for such conditions. Colloidal suspensions containing nano-sized particles (1-100nm) in a basefluid are generally termed nanofluids. Rheological characteristics of various nanofluids prepared from different types of nanoparticles have been thoroughly studied in the past. However, the effect of nanoparticles on drilling fluids at high temperature and pressure conditions are not investigated in detail. In the present work, the rheological study of nanomud suspensions prepared by adding multi-walled carbon nanotubes (MWCNT) into the drilling fluid is conducted. A Nanofluid suspension based on CNT is deemed advantageous due to its high thermal conductivity, and efficient mechanical properties. High-pressure and high-temperature rheology of a nanomud suspension is reported here. The CNT-drilling mud nanofluids (nanomuds) are prepared using a top-down approach. Initially, the water-based drilling mud (base fluid/basemud) is prepared. The Water Based Mud (WBM) used in this study contain Bentonite (1%) and Barite (7%) which makes up the total percentage of solids by volume of the whole mud with a 12.5 ppg (pounds per gallon) as the final weight. The Bentonite was initially mixed with the water and seated for approximately 16 hours of hydration to form Prehydrated Bentonite or PHB. A high-pressure high-temperature (HPHT) viscometer (Chandler Viscometer 7600) is used for the rheological analysis. The viscometer is designed for rheological studies of drilling fluids while subjected to varying drilling well conditions in accordance with ISO 10414-1, 10414-2 and API 13 recommended practices. As the variation of the pressure and temperature would influence the measured viscosity values of the suspension, two independent experimental schedules are performed. Automated measurements are recorded once the pressure and temperature values of the sample have reached the set values. Viscosity values are measured at a maximum pressure of 170 MPa with temperatures ranging from ambient to 180°C. The effect of MWCNT nanoparticle concentration and variation in shear rate are also investigated. A shear thinning non-Newtonian behavior is observed for the basemud and the nanomud samples at all pressures and temperatures. The basemud showed an increase in viscosity with an increase in pressure. However, with MWCNT particle addition, this trend is observed to have reversed.

Modeling the diffusion of residential solar photovoltaic (PV) systems in their social, political and economic context is crucial to help policymakers assess which policies may best support adoption. Current models of renewable energy adoption [1, 2, 3, 4] assume regulatory and incentive frameworks that do not apply to Gulf Cooperation Council (GCC) states, where energy tariffs are strongly subsidized, tax credits are not viable due to the lack of personal income tax, and support for distributed generation through grid access policies such as the Feed-in Tariff and Net Metering is not available. The goal of this study is to address this gap by analyzing the impact of home ownership, the falling cost of PV, the reduction of electricity subsidies, the introduction of a carbon tax, and the diffusion of innovation on the residential adoption of solar PV technologies in Qatar. Our objective is to develop a social simulation platform that helps policymakers and other stakeholders assess the optimal regulatory framework to promote the adoption of building-integrated PV systems in Qatar and other countries which share a similar geographical, political, economic and social context. We present an agent-based model for residential adoption of solar photovoltaic (PV) systems in the state of Qatar as a case study for the Arabian Gulf Region. Agents in the model are defined as households. Each household corresponds to a dwelling in the Al Rayyan municipality of Qatar that is either owned (by citizens) or rented (by expatriates). The objective of the model is to evaluate PV adoption in terms of these two household cohorts under diverse regulatory and incentive scenarios. In the present state of affairs, only Qatari citizens can own property in Al Rayyan and Qatari households are exempt from electricity charges. Therefore, home owners are Qataris who have free electricity, while renters tend to be expatriates who pay for electricity. The more competitive the cost of electricity from residential PV systems is as compared to the electricity tariff, the more likely are household agents to adopt solar PV. Several factors can contribute to make the cost of electricity from residential PV more competitive, including: the falling cost of PV due to increasing technology maturity the reduction of subsidies for electricity and the gas used for electricity production the introduction of a carbon tax the extension of the electricity tariff to Qatari households the neighborhood effect, which implements peer effects on the diffusion of PV innovation as a percent discount on residential PV cost. We compute solar PV adoption as resource limited exponential growth. Households adopt solar PV with a probability established by the logistic function in (1), where L is a scaling constant, e is the natural logarithm, x is the cost of electricity from residential PV systems and k is a parameter which determines the slope of the adoption curve. We set L = 1 to normalize the output of the logistic function as a probability. For the k parameter, we select a value (k = 0.59) that in the null-hypothesis scenario yields a PV market share that is equivalent to the innovator cohort of adopters in Rogers' adoption/innovation curve (2.5%) [5]. According to Rogers, “innovators are active information seekers about new ideas”, who are close to the scientific community and other innovators, have financial liquidity, and are willing to take high risks to pursue their vision. The rationale for restricting adopters to innovators in the null hypothesis scenario is that only eco-warriors with financial means and high technology awareness would adopt in the absence of incentives, with high PV costs.(1) f (x) = L / 1 + e^(-k*x) At each simulation tick, each household agent that has not adopted yet, is presented with the opportunity of doing so. Adoption is determined randomly according to the output of the logistic function in (2): a random probability p is generated, and if the probability of adoption as calculated by (1) is greater or equal to p, adoption occurs. We analyze three alternative simulation scenarios: Scenario 1 – Business as usual: no measures are introduced to incentivize PV, the neighborhood effect is active, and the price of PV falls due to increasing technology maturity Scenario 2 – 40% of gas and electricity subsidies are curtailed, the neighborhood effect is active, a carbon tax of $8/tCO2e is introduced, the price of PV falls due to increasing technology maturity, and citizens continue to have free electricity Scenario 3 – same as scenario 2, with the variant that citizens to pay for electricity. As baseline, we establish a null hypothesis scenario, which is the same as scenario 1, except that the price of PV does not fall due to increasing technology maturity. Details of the simulation results are provided in the attached file to this submission. Our study suggests that Qatar's residential PV adoption is strongly promoted by the falling cost of PV and can be further facilitated through the reduction of electricity subsidies and the extension of the electricity tariff to Qatari households, which are currently exempt. The introduction of a carbon tax can also play a role in accelerating residential PV adoption, if above $8 per metric ton of carbon dioxide equivalent. The ensuing PV adoption rates would help facilitate the national targets of 2% electricity production from solar energy by 2020 and 20% by 2030.

References

[1] Zhao, J., E. Mazhari, N. Celik, Y.-J. Son. “Hybrid agent-based simulation for policy evaluation of solar power generation systems”. Simulation Modeling Practice and Theory 19, (2011): 2189‒2205.

[2] Paidipati, J., L. Frantzis, H. Sawyer, A. Kurrasch. “Rooftop photovoltaics market penetration scenarios”. Navigant Consulting, Inc., for NREL: February, (2008).

[3] Drury, E., P. Denholm, R. Margolis. “Modeling the US rooftop photo- voltaics market”. In National Solar Conference 2010, 17‒22 May 2010, Phoenix, USA, (2010).

[4] Graziano, M. and K. Gillingham. “Spatial patterns of solar photovoltaic system adoption: the influence of neighbors and the built environment”. Journal of Economic Geography 15, (2015): 815‒839.

[5] Rogers, E. M. Diffusion of innovations. New York, Free Press of Glencoe, RS(N), (2010).

Soluble conjugated polymers have nowadays attracted broad academic and industrial spotlight as innovative materials of easy tuneable optical and electronic properties.1 These properties translate into various optoelectronic applications such as organic solar cells, light-emitting diodes (LEDs), and thin film transistors. The pivotal parameters that define characteristics of conjugated polymer based devices are of chemical (structure, solubility, mass) and mechanical (macroscopic) nature.2 Although the physical properties CPs is determined by designed chemical structure, critical alterations result from variations of the nanostructure of the polymer in its solid state.3 Therefore the complete optoelectronic potential of CP based device can be fully assessed only with the optimal conjugated chains alignment. We envisioned thermal and UV induced post processing of conjugated polymers predesigned to dramatically change their properties in given conditions by removal of nonconductive side chains and reducing interlayer distance.

About one third of the oil and gas extracted worldwide comes from offshore sources. There is currently thousands of large-scale oil and gas platforms spread across the seas and coastal oceans, from the North Sea to the seas of South Asia. Although their primary purpose is not related to enrichment of biodiversity, gas and oil platforms can act as large and complex artificial marine habitats for a wide range of marine organisms, including sessile invertebrates and fishes. These structures have shown to enhance ecosystem function, especially secondary fish production, relative to adjacent natural reefs, besides being among the most productive marine fish habitats globally. Indeed oil platforms constitute important fish aggregating devices, especially in areas subjected to a range of environmental perturbations. Hard substratum availability combined with exclusion zones around these structures allows for the development of diverse fish assemblages. We carried out the first assessment of vertical distribution, diel migration, taxonomic and functional diversity of fishes at offshore platforms in the Arabian Gulf. Video footages were recorded at the Al Shaheen Oil Field, between 2007 and 2014 using a Remotely Operated Vehicle (ROV). Indeed diving and snorkeling are strictly forbidden in the exclusion zone around offshore platforms, precluding conventional monitoring techniques such as underwater visual census, collection of sessile organisms, etc. Routine inspection and maintenance surveys, however, are conducted to monitor the state of underwater structures using ROVs. A total of 4,510 video files, containing 120 hours of underwater video recordings, were provided by Maersk Oil Qatar A/S. These videos were recorded over six years (2007, 2009, 2010, 2011, 2012 and 2014), during day and night, at the 9 platform locations (A-I) within the Al Shaheen Oil Field using a ROV of the model SAAB Seaeye Surveyor Plus 229. To assess the local fish community, a total of 242 videos amounting to twenty-one hours of observation were selected randomly, however, if no fish appear in a selected video a new video was randomly selected from the list. This work represents the first assessment of reef fish communities inhabiting oil and gas platforms in the Arabian Gulf. A total of 12,822 fish, belonging to 83 taxonomic groups were recorded around the platforms. Among them, two species are first recorded for Qatari waters: Cyclichthys orbicularis and Lutjanus indicus. In addition two chondrichthyes, one endangered (Stegostoma fasciatum) and a vulnerable species (Taeniurops meyeni), were also observed across the platforms. Several trends were found in the vertical distribution of the fish community, most species were observed between 20 and 50 m depth and higher fish abundance recorded in the upper layers, down to 40 m depth and decreasing with depth. Vertical variation, however, in fish diversity was generally not accompanied by differences in vertical movements. The vertical variation, however, in fish diversity was not accompanied by differences in vertical movements of the fish. These results suggest that the vertical zonation pattern does not change, or only changes slightly, on a daily basis. The mean centers of mass of the most abundant fish species did not overlap, likely due to potential competition or niche differences. The dominant trophic groups were carnivores and invertivores, being well represented at each depth range (each spanning 10 m) from surface to seabed. Diel vertical movement was observed only for Acanthopagrus bifasciatus, which was concentrated at shallow depths during the daytime but migrated to deeper layers at night. The functional indices showed no significant differences between water depths or diel cycles (day / night). Besides the temperature variation, the reduced light penetration due to platform structures makes difficult the algal growth necessary for browsing herbivorous fish. Thereby, the effect of sunlight penetration may be reflected in the vertical distribution of herbivorous fish, which are rare in deeper layers. Planktivores are densely grouped within and just below the thermocline, which is located around 18 m during summertime. The study demonstrates that oil platforms represent a hotspot of fish diversity and interesting sites for studying fish communities, abundance and behaviour.

Designing Photo Absorbing Materials by Cation Substitutions for Photovoltaics Merid Legesse1, Heesoo Park1, Fedwa El Mellouhi1, Sergey N Rashkeev1, Sabre Kais1, 2, 3, Fahhad H Alharbi1, 3 1Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, Doha, Qatar. 2Department of Chemistry and Physics, Purdue University, West Lafayette, Indiana 46323, USA. 3College of Science and Engineering, Hamad Bin Khalifa University, Doha, Qatar. Email: [email protected]. Recently, significant research efforts have focused on some emerging solar cell technologies such as dye-sensitized solar cells, perovskite photovoltaics, etc. However, these technologies face many challenges. In this talk, we will present a new family of light absorbing materials so-called pyroxene silicates. These materials are abundantly present in the earth crust however, bandgaps of naturally formed pyroxene silicates such as NaAlSi2O6 are quite high (∼5 eV). Therefore, it is important to find a way to reduce bandgaps below 3 eV to make them usable for optoelectronic applications [1, 2, 3]. Using first-principles calculations we investigated the possibility of band structure engineering of pyroxene silicates with chemical formula A+1B+3Si2O6 by proper cation substitution (A+ =  Na, NH4+, PH4+, SH3+, CH3NH3+, CH3PH3+, CH3SH2+ and B3+ =  Al3+ Ga3+, In3+, Tl3+). We found that appropriate substitutions of both A+ and B3+ cations can reduce the bandgaps of these materials to as low as 1.31 eV. In this talk, we will also discuss in details how the bandgap in this class of materials is affected and thermodynamic stabilities. We would like to thank Qatar National Research Foundation (QNRF) for the support (Grant No. NPRP 7-317-1-055. References (1) A.A.B. Baloch, S.P. Aly, M.I. Hossain, F. El-Mellouhi, N. Tabet, and F.H. Alharbi, Sci. Rep. 7, 11984 (2017). (2) F. El Mellouhi, A. Akande, C. Motta, S.N. Rashkeev, G. Berdiyorov, M.E.A. Madjet, A. Marzouk, E.T. Bentria, S. Sanvito, S. Kais, and F.H. Alharbi, ChemSusChem 10 1931 (2017). (3) F.H. Alharbi, S.N. Rashkeev, F. El-Mellouhi, H. P. Lüthi, N. Tabet, S. Kais, npj Comput. Mater 1, 15003 (2015).

Drilling phase is one of the most important parts of developing a field. The durability of the well and its performance is greatly related to the quality of the drilling. A good drilling will also have an effect on how fast the project can start make profits as the drilling phase become shorter and more efficient. There are number of different factors that can hinder the quality of the drilling job and in some cases stop it or damage the wellbore and cause catastrophic disasters. Barite sagging is a one of the main causes of damage in the wellbore during the drilling stage. Any drilling job needs a drilling fluid that can provide the engineers with: enough hydrostatic pressure to prevent the well from collapsing in, removing the drilling cuts to the surface, cools down and lubricates the drill bit during the drilling job, suspend the drilling cuts within itself during the drilling and when drilling is stopped,seal the permeable zones in the wellbore to prevent lost circulation, control the corrosion caused by corrosive gasses such as H2S, provide hydraulic energy to the bit to fasten and improve the drilling and finally help the engineer to the cementing and completion after the drilling was done. Barite Sag is a common phenomenon that occurs while drilling for oil and gas. Barite, BaSO4 is a weighing agent used to increase the density of drilling fluids to a desired level. It has a high density of 4.2 g/cm3. The problem that occurs in this phenomenon is that as the mud is circulated through the borehole, the barite that was dissolved in the mud starts separating from the liquid phase and settles down. This separation of barite from the aqueous phase creates an undesired density gradient and causes a lot of further problems. Barite sag can occur in both conventional and deviated wells. In vertical wells, higher density drilling fluids or barite-rich phase settles on the bottom of the well bore while the lower density fluid form layers on the upper part of the column. This usually occurs during static conditions i.e. when drilling is stopped or very low shear rate (rpm). Additionally, a very low shear-rate viscosity can also result in barite sag. However, deviated wells are more susceptible to barite sag as in deviated wells, gravity induces an additional settling effect which results in sediment beds of barite at the bottom of the borehole. In deviated wells, Boycott effect is the reason for barite sagging. In an inclined tubing, the vertical distance of the settling particles is greatly reduced as compared to that in vertical columns. Hence the process of sedimentation is accelerated. Barite sagging can cause some serious problems during drilling operations. These problems are: loss of mud circulation, well bore instability, and uneven mechanical friction which can cause pipes and tools to get stuck downhole. Barite sagging, if not controlled properly, can lead to a complete shutdown and well abandonment. Hence, this study is being conducted to look in detail at the various chemical and physical factors, that affect barite sag, so that more viable and optimal solutions can be derived to control the extent of barite sag. Barite sagging is just a general term used to describe the phenomenon of which the weighting material detaches itself from its own liquid phase and slowly settles down the wellbore. But many more specific examples of barite sagging have been looked into and researched to further expand our understanding of this phenomenon. From dynamic to static sagging, in wells that are vertical, horizontal or deviated, all of these scenarios have been heavily examined and studied. The extent of the research that has been done in regards to barite sagging is surely well deserved as barite sagging can cause major problems while drilling in the field such as loss circulation, sudden changes of density in the drilling fluid which could further escalate into a blowout. Problems with cementation, well control issues and stuck pipe, all have been encountered mainly due to barite sagging. The research papers available look into a wide range of aspects related to barite sagging, but I will mainly look at the research conducted that studies adding different substances into the drilling fluids and comparing the effects that the new substances can cause to the sagging affect. Another major topic that I will try to cover is the different methods that have been used through the years to measure barite sagging in the laboratory environments.

Alessandro Sinopoli, a Michael Wasielewski, b Muhammad Sohail. a aQatar Environment & Energy Research Institute, Hamad Bin Khalifa University, PO Box 5825, Doha, Qatar; bDepartment of Chemistry and Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, USA. The use of fossil fuels, especially natural gas, which has a lower carbon burden than oil or coal, will continue to dominate the energy market for the next several decades. In order to mitigate the large amounts of CO2 released into the atmosphere, it is essential to have clean ways of converting the CO2 back into a high energy density liquid fuel. Benchmark catalysts for CO2 reduction typically employ second and third row transition metals like palladium, iridium, and rhenium. The rarity, cost, and environmental ramifications of mining large quantities of such precious metals deter scaling up the usage of such catalysts. Developing a CO2 catalytic system that uses earth abundant first row transition metals like manganese, will push the field away from rare earth metal catalysts. While still an emerging field, transition metal-based catalysts can be successfully integrated in electrochemical and photoelectrochemical devices for CO2 reduction. Inside this class of compounds, developing manganese-based systems remains an extremely promising strategy for the advent of low cost but at the same time efficient molecular systems for CO2 reduction. We will therefore investigate Mn(bpy)(CO)3Br and its related derivatives that have recently been shown to efficiently reduce CO2 to CO. More importantly, none of these Mn-bipyridine complexes have yet been integrated with a covalent photo-driven source of electrons and this will be the main synthetic and experimental challenge within this project. Aromatic organic anions (radical anions or closed shell dianions) are reactive species involved in various chemical transformations. The photochemistry and photophysics of these species have been the subject of extensive study since they have been implicated in many photo-induced electron transfer processes, and are suggested to be powerful reducing agents. Such properties were substantiated by the observation of rapid electron ejection to give solvated electrons, electron-cation pairs, or reduced electron acceptors upon photolysis of aromatic anions (e.g. sodium pyrenide or biphenylide). We envision that the high reducing power (up to − 3 V vs. SCE) of excited monoanions or dianions of aromatic diimides can be exploited for CO2 reduction catalysis. In particular, the anions of PDI perylene-3,4:9,10-bis(dicarboximide) and its homolog naphthalene-1,8:4,5-bis(dicarboximide) (NDI) will be used as the primary photosensitizers in this study. These planar, chemically robust, redox-active compounds are widely used as industrial pigments, supramolecular building blocks, photooxidants, and n-type semiconducting materials. In the effort of integrating NDI and PDI units in the design and development of manganese based photocatalysts, experiments will be carried out in two stages. In the first stage, we will synthesise photosensitizer systems designed specifically to act as catalysts, so that their structures and properties can be determined. Figure 1. Examples of Mn-based catalysts designed for this project. The structures depicted in Figure 1 are examples of PDI and NDI photosensitizer systems designed for this project. For example, in the molecule on the left (Figure 1), two easily reducible PDI molecules are covalently attached to the bpy ligand. One-electron reduction of PDI will produce the stable PDI-• radical anion. The structure of the designed manganese complexes, the dynamics of CO2 binding, and subsequent protonation of the bound Mn carboxylate will be studied using femtosecond transient absorption spectroscopies with both UV-Vis and mid-IR probing as well as and femtosecond stimulated Raman spectroscopy (FSRS). The second stage of the experiments will study the laser-generated Mn(0)(bpy)-1(CO)3-based catalyst followed by CO2 binding and protonation. For this we will perform steady-state photolysis experiments on the systems in DMF with varying amounts of HBF4 and CO2 up to the limit of a saturated solution of CO2 in DMF at 25 °C and 1 atm, which is about 0.14 M. These studies will look for products generated following one-electron reduction of the Mn catalysts. We will quantitate the yield of CO produced by the overall photoreaction using a 16-sample parallel system in which the samples are illuminated using filtered LEDs and a parallel, continuous gas sampling system connected to a gas chromatograph. The system will be calibrated with appropriate standard gas mixtures, and a full range of conditions and appropriate control experiments will be performed by varying the concentrations of catalyst, CO2, HBF4, and sodium ascorbate in the solution. Solar energy, an abundant resource in Qatar, can drive CO2 reduction to produce both liquid solar fuels and potentially high value chemicals. In this regard, our study will represent the birth of a new generation of efficient photocatalytic systems for CO2 reduction by coupling robust light harvesting molecules with earth abundant transition metals like manganese.

The development of nanoscience and technology has devoted significant attention to conducting studies on hollow particles. Among the available materials, mesoporous silica nanoparticles have recently gained attention as potential nanocontainers due to their high stability, large surface area, controllable pore diameter and easy surface functionalization as they can store and release organic or inorganic molecules of different sizes and functionalities. The aim of this work is to study the use of mesoporous silica as a potential reservoir for corrosion inhibitor for active corrosion protection of carbon steel and using epoxy encapsulated halloysite nanotubes for the self healing process of the epoxy based coatings. The synthesized mesoporous silica particles were characterized by using XRD, FTIR and SEM. Mesoporous silica particles loaded with diethylenetriamine (DETA) were embedded into the epoxy polymer along with the halloysite nanotubes (HNTs) encapsulated with epoxy monomer and amine immobilized in mesoporous silica with a weight ratio of 5 wt% of mesoporous silica. Kinetics of release of corrosion inhibitor was evaluated by electrochemical impedance (EIS) measurements in 3.5 wt% NaCl solution. The EIS analysis confirms that the release of inhibitor during the corrosion process has significantly improved the anticorrosion properties when compared to the epoxy coated sample without any corrosion inhibitor. The self healing phenomenon in the scratched epoxy coated sample was monitored by SEM during different time intervals. The SEM results showed that that the epoxy pre-polymer was slowly released into the crack.Upon release, the epoxy pre-polymer came into contact with the amine immobilized in mesoporous silica and cross-linked to heal the scratch over the sample surface. This study suggests that these novel coatings may have some potential applications in the oil and gas industry.

Thermal Hysteresis of Palladium encaged inside Mesoporous Silica catalyst for Low Temperature CO oxidation Rola Al Soubaihi 1,2, Joydeep Dutta2 Liberal Arts and Science Program, Virginia Commonwealth University-Qatar, Doha, Qatar Department of Applied Physics, KTH Royal Institute of Technology, Stockholm, Sweden Carbon Monoxide (CO) is colorless, odorless gas produced from incomplete combustion of carbon fuel under conditions with a limited supply of oxygen. Catalytic oxidation is one of the effective methods of removing CO and convert it to CO2. [1] Catalyzed CO oxidation reaction finds applications in many fields such as environmental protection, air purification for buildings or cars, orbiting, closed-cycle CO2 lasers, gas masks for mining applications, CO detectors[2-3]. Depending on their size, shape, and preparation conditions, Nanocatalysts can exhibit unique properties (electrical, optical, magnetic, and catalytic) which are different from their bulk material properties [4-6]. The surface of nanomaterials contains large number of high energy defects such as surface and edge atoms that can provide active sites for catalyzing surface reactions by lowering the activation energy [7-8]. Supported Palladium catalysts are known for their high activity, recyclability, and their cheap cost when compared to platinum catalysts. Support plays a crucial role in the synthesis of such catalysts. In this regard support can reduce the amounts of the metal and ensure a good dispersion, and increase their thermal stability. Mesoporous materials with large internal surface areas (>1000 m2/g) and narrow pore size distributions can be an ideal support for Palladium based catalysts [9-10]. Silica are well known for structural and thermal properties and allow anchoring of catalytically palladium active species onto their surfaces. Silica can provide enormous beneficial features to enhance the catalytic activity such as high surface area, high porous, high thermal insulation, and local heating and heat retention [11-13]. Here, we report for the first time exceptional catalytic CO oxidation on Pd supported on mesoporous SiO2 with good stability and recycling behavior under heating and cooling conditions with wide CO Thermal hysteresis (close to 200 °C). We attribute our results to the phase transformation of Palladium to palladium oxide intermediate at different temperatures during the heating and cooling cycles and the structure and the local environment of the palladium since Pd clusters are small and highly dispersed on the silica surfaces and encaged inside the pores. References [1] S. Biswas, K. Mullick, S. Y. Chen, A. Gudz, D. M. Carr, C. Mendoza, et al., «Facile access to versatile functional groups from alcohol by single multifunctional reusable catalyst,» Applied Catalysis B-Environmental, vol. 203, pp. 607–614, Apr 2017. [2] X. Zhang, Zhenping Qu, Xinyong Li, Meng Wen, Xie Quan, Ding Ma, and Jingjing Wu., «Studies of silver species for low-temperature CO oxidation on Ag/SiO 2 catalysts.,» Separation and Purification Technology, vol. 3, pp. 395–400., 2010. [3] P. A. Wright, Srinivasan Natarajan, John M. Thomas, and Pratibha L. Gai-Boyes, «Mixed-metal amorphous and spinel phase oxidation catalysts: characterization by x-ray diffraction, x-ray absorption, electron microscopy, and catalytic studies of systems containing copper, cobalt, and manganese,» Chemistry of materials vol. 5 pp. 1053–1065., 1992. [4] A. Cubo, J. Iglesias, G. Morales, J. A. Melero, J. Moreno, and R. Sanchez-Vazquez, «Dehydration of sorbitol to isosorbide in melted phase with propyl-sulfonic functionalized SBA-15: Influence of catalyst hydrophobization,» Applied Catalysis a-General, vol. 531, pp. 151–160, Feb 2017. [5] W. Fang, Y. C. Deng, L. Tang, G. M. Zeng, Y. Y. Zhou, X. Xie, et al., «Synthesis of Pd/Au bimetallic nanoparticle-loaded ultrathin graphitic carbon nitride nanosheets for highly efficient catalytic reduction of p-nitrophenol,» Journal of Colloid and Interface Science, vol. 490, pp. 834–843, Mar 2017. [6] M. V. D. Fernandes and L. R. D. da Silva, «Structural analysis of mesoporous vermiculite modified with lanthanum,» Materials Letters, vol. 189, pp. 225–228, Feb 2017. [7] A. K. Herrmann, P. Formanek, L. Borchardt, M. Klose, L. Giebeler, J. Eckert, et al., «Multimetallic Aerogels by Template-Free Self-Assembly of Au, Ag, Pt, and Pd Nanoparticles,» Chemistry of Materials, vol. 26, pp. 1074–1083, Jan 2014. [8] R. Muller, S. H. Zhang, B. Neumann, M. Baumer, and S. Vasenkov, «Study of Carbon Dioxide Transport in a Samaria Aerogel Catalyst by High Field Diffusion NMR,» Chemie Ingenieur Technik, vol. 85, pp. 1749–1754, Nov 2013. [9] Al-Oweini, S. Aghyarian, and H. El-Rassy, «Immobilized polyoxometalates onto mesoporous organically-modified silica aerogels as selective heterogeneous catalysts of anthracene oxidation,» Journal of Sol-Gel Science and Technology, vol. 61, pp. 541–550, Mar 2012. [10] B. N. Bhadra, P. W. Seo, J. W. Jun, J. H. Jeong, T. W. Kim, C. U. Kim, et al., «Syntheses of SSZ-39 and mordenite zeolites with N,N-dialkyl-2,6-dimethyl-piperidinium hydroxide/iodides: Phase-selective syntheses with anions,» Microporous and Mesoporous Materials, vol. 235, pp. 135–142, Nov 2016. [11] S. Dilger, C. Hintze, M. Krumm, C. Lizandara-Pueyo, S. Deeb, S. Proch, et al., «Gas phase synthesis of titania with aerogel character and its application as a support in oxidation catalysis,» Journal of Materials Chemistry, vol. 20, pp. 10032–10040, 2010. [12] A. K. Herrmann, P. Formanek, L. Borchardt, M. Klose, L. Giebeler, J. Eckert, et al., «Multimetallic Aerogels by Template-Free Self-Assembly of Au, Ag, Pt, and Pd Nanoparticles,» Chemistry of Materials, vol. 26, pp. 1074–1083, Jan 2014. [13] R. Muller, S. H. Zhang, B. Neumann, M. Baumer, and S. Vasenkov, «Study of Carbon Dioxide Transport in a Samaria Aerogel Catalyst by High Field Diffusion NMR,» Chemie Ingenieur Technik, vol. 85, pp. 1749–1754, Nov 2013.

Food handling practices (FHP) is one of the most important stage where microbes can be introduced into produce through the infected food handlers or by cross-contamination. The fresh produce market in Doha, Qatar is the major market from which most of the food businesses, restaurants, super markets, and consumers obtain their fresh produce. Produce is handled by workers with no or minimum knowledge on safe produce handling practices. This study was carried out to assess the food safety knowledge and self-reported handling practices applied by produce handlers working at this major produce market in Qatar. About 120 produce handlers were surveyed using a systematic questionnaire (No. QU-IRB 509-E/15) to determine their food safety knowledge and attitudes during handling of fresh produce in January 2016. In addition, hand-swab samples and work uniform photos were collected. A standard microbial count were applied on the collected swabs to determine the hands' hygiene levels of the workers. The identification of microorganisms isolated from their hand swabs was carried out using MALDI-TOFF. The survey results revealed that the hygiene practices and food safety knowledge among produce handlers working at this produce market are insufficient. It was determined that none of the handlers received any food safety training on safe produce handling practices before joining the work at the market. Most of the workers' age was below 50 yrs (82.5%), about 37% of them was between 31 and 40 years old. Regarding educational level; 57.5% of them had middle school degree or below. More than 60 % of them claimed to wash their hands 4–5 times per duty time. The microbial hand-swabbing analyses demonstrated the presence of Enterococcus faecium, Klebsiella pneumoniae, Staphylococcus spp., and Bacillus circulans. Overall, these results are significant because they highlight the need to promote additional efforts that might assist in developing necessary intervention strategies to improve the conditions at this major market and prevent future foodborne illness outbreaks linked to produce sold in Qatar.

Study of polyaniline-silver nanocomposite as humidity sensor J. Bhadra, A. Popelka, N. J. Al-Thani, A. Abdulkareem Center for Advanced Materials, Qatar University, Qatar Abstract In this piece of work focus on fabrication of resistive type humidity sensor using polyaniline-silver nanocomposite (PPVA-Ag). Four different nanocomposites using four concentrations of silver (0.5,1.0, 1.5 and 2.0 M) and polyaniline (PANI) dispersed in polyvinyl alcohol matrix (PVA). PANI, and PVA concentrations are kept constant. Thin PPVA-Ag film on interdigited gold electrode fingers gives excellent sensitivity towards humidity at room temperature. 1. Introduction Since last few decades the information of nanoscience and nanotechnology has been explored extensively to obtain functionalized nanomaterials. One such category of nanomaterial is the polymer- metal nanocomposite, with enhanced mechanical, elastic, optical, electrical and dielectric properties [1]. Polymer nanocomposites are materials with nanosized one dimensional inorganic filler particles (around 10–100 ˚A), dispersed in an organic polymer matrix. An important parameter which has significant importance in many industries such as food, agricultural, clinical equipment and electronics is humidity, it is considered to be one of the most frequently measured physical parameters [2-3]. With the advancement in moisture sensitive technologies, research to achieve high efficient, low cost, reliable and miniature size of material sensitive to humidity change has gained acceleration. As among metal nanoparticles, Ag has high electrical and thermal conductivities, so the composite of Ag dispersed in PANI-PVA matrix gives rise to a functional materials, with improved antimicrobial activity and sensitivity towards humidity. This paper we focus on surface analysis of the thin film obtained using scanning electron microscopy and study on the humidity sensitivity. 2. Methods 2.1 Synthesis of Ag nanoparticles Four different concentrations of silver nitrate (AgNO3) is dispersed in aqueous PVA solution under constant stirring and heating at 60°C followed by photo reduction using UV-lamp having wavelength 390 nm for 24 hours. After exposing the above solutions with UV light for 24 hours, finally, yellowish-red colloid of Ag nanoparticles with average diameters of ∼30 nm and ∼70 nm uniformly dispersed in PVA are obtained. 2.2. Synthesis of PANI-Ag nanocomposite and pure PANI: The PANI-Ag nanocomposite blend is synthesized by in-situ chemical polymerization (Figure-1) of aniline monomer in the colloid solution obtained from section 2.1. During this process, aniline-DBSA is added to the Ag-PVA colloidal solution, followed by addition of the aqueous APS solution dropwise. The resulting blend mixture is left to react for 24 h under constant stirring at 5–10 °C. The colloidal solution obtained are used to prepare thin film on glass slide and interdigitated gold electrode washed with DI water and acetone and dried. Keeping the other concentrations and methods constant four different PPVA-Ag nanocomposites are prepared with 0.5, 1.0,1.5 and 2.0 M of AgNO3.

Figure 1: Steps followed to prepare PANI-Ag nanocomposites 2.3. Study of Effect of humidity on the PPVA-Ag nanocomposites A homemade setup is used to study of effect of humidity on the PPVA-Ag nanocomposites coated on the interdigited gold electrode fingers using dropcast method. The humidity chamber consists of transparent polymer with three holes for nitrogen gas inlet, humidity inlet and electrical wires for conductivity measurement. The schematic diagram of the setup is shown in the Figure 2. Humidity meter and the polymer coated electrodes are placed inside the chamber. The control of humidity inside the chamber has been done using humidifier and N2 gas during the experiment. And keithley sourcemeter 2400 has been used to measure the resistivity.

Figure 2: Schematic diagram of humidity measurement setup 3.1 Scanning Electron Microscopy studies The results of surface morphology analysis using SEM are shown in Figure 3. From the images it is seen that Ag nanoparticles are well dispersed in PANI-PVA matrix. Such results are observed because chemical method of preparation has been adopted. With the increase of Ag concentration there are not much changes in the particle size, however the degree of agglomeration increase, that causes the increase in surface roughness.

Figure 3: SEM images of (a) PPVA-Ag-0.5, (b) PPVA-Ag-1.0, (c) PPVA-Ag-1.5 and (d) PPVA-Ag-2.0. 3.2 Effect of Humidity We have used all the four types of composites for this measurement. For this measure at first the humidity chamber is blown with N2 gas for few minutes to reduce the humidity to RH 20 % at room temperature. Once the reading in the humidity meter is stable, resistance of the thin film has been measured. Each time for resistance measurement voltage reading for 10 mA current has been repeated for 10 times with time sweep of 500 ms. In order to reduce the error we repeated the whole measurement for 15 times at each RH measured, shown in Figure 4 for PPVA-Ag 1.0M sample. During the experimental process each step is maintained at constant parameters till the electrical signals reading reached a steady value. All the four plots describing resistance change as a function of humidity for each composite measured has been shown in inset of Figure 4. It is has been observed that, there is not much difference between the resistance curves as a function humidity for all the four composites. As the humidity increases water vapour contributes to the reducing the conductivity in two ways, firstly water molecules donate electrons to the valence band of PANI molecules, therefore decreasing the number of holes and increasing the bandgap and secondly as PVA is hydrophilic, so it absorbs water molecules and get expanded, this leads to increase the interparticular distances between the conducting fillers of the composites, and reducing the conductivity. Because of these two reasons higher the RH level lower the electrical conductivity.

Figure 4: The effect of Relative humidity on the resistance of PPVA-Ag-1.0M, Inset The effect of Relative humidity on the resistance of four PPVA-Ag samples.4. Reference: [1] M. Joulazadeh, A. H. Navarchian, Advances in Polymer Technology, 33, 2014, 21461. [2] A. T. Ramaprasad, V. Rao, Sens. Actuat. B, 148, 2010, 117–125. [3] J. Wang, X. Wang, X. Wang, Sens. Actuat. B, 108, 2005, 445–449

Energy policy and security of a country heavily depends on its resources, geography, demographics and economic structure. While most active strategies include the discovery, extraction and utilization (through new infrastructure) of energy resources, a more subtle approach to reduce energy demand and increase energy security is to use the resources more efficiently and conserve them to increase the life span in which they can be used. This understated approach is the implementation of energy efficiency policy. Energy efficiency taken holistically includes the improvements in technology as well as changes in human behavior to do a task with less amount of energy. While different studies have shown the impact of efficiency policies and programs on individual economic sectors (i.e. industrial, commercial, residential, agriculture and transport), a complete overview of the impact of efficiency on economy has received little attention. This approach overlooks the interdependence of each economic sector and their influence on each other. Similarly, the rebound effect, a consequence and a major element of efficiency is avoided in these studies as well. Rebound effect is the increase in energy consumption because of lower prices of energy commodities due to increase in efficiency. The rebound effect not only has a direct impact on the individual sector, like driving more miles because of a more efficient vehicle, it has also indirect consequences, such as going to a vacation because of the money being saved through efficiency. Thus, the study of efficiency, its dynamic influence and calculating a realistic magnitude are required to ideally approach the costs and benefits of implementing an efficiency program or policy. This research looks into the economy wide impacts of energy efficiency and the dynamic interaction and impacts of each sector on the other. First, a hierarchal list of variables, which influence the energy supply and demand of any economy, is created. Second, a list of indicators which measure the health of an economy is formed. Using data for the top 10, oil and gas producing countries (these countries give a good mix of economies which heavily rely on oil and gas rents such as Qatar, UAE, Saudi Arabia as well as economies, which produce some of the highest energy resources, while relying very little on its influence on their economies, such as US, Norway), the magnitude and impact of each variable to the economy is calculated. These variables are then used to create a system dynamics model which includes the production, conversion and transportation of energy from different sources to consumption in different sectors. Estimated energy efficiency measures and impacts are then incorporated into the systems model to see the effect of efficiency as well as the rebound effect on the economy. A major goal of this study is to find the future impacts of energy efficiency policies and the consequences of these policies, if they are not implemented because of financial constraints or present gains (such as more revenues from greater resource production). The cost benefits as well as the effective implementation of efficiency measures are calculated and compared using the economic indicators obtained in the second step. Finally, these indicators can be used to determine as to why some countries are more efficient with their energy resources as compared to others.

Energy consumption for air conditioning purposes accounts for 60-80% of electricity used in Qatar. As District Cooling Plants (DCPs) has a potential to reduce energy consumption and CO2 emissions, Qatar and GCC are continuously shifting paradigm towards adoption of DC plants to satisfy the rapidly growing demand in all sectors. However, DC plants usually rely on wet cooling towers for disposing the excess heat to the ambient. Hence the efficiency of DCPs is significantly influenced by the cooling tower effectiveness in heat disposal, which is dominated by latent heat or evaporation of water in a counter atmospheric current air stream. Operation district cooling plants (DCPs) under extremely high humidity in summer represents one of the major thermodynamic limitations in terms of maintain the outlet water temperature of cooling towers (i.e. chiller's condenser cooling water) as low as possible to guarantee higher efficiency of DCPs. The cooling tower efficiency degrades considerably at higher relative humidity of air, which approaches saturation limits in summer, where the cooling demand is high. The ambient wet-bulb (WB) temperature is a limiting factor for the capacity of cooling towers (CT), which determines the inlet cooling water temperature to the chiller's condenser (outlet water temperature from the CT). Due to prevailing weather conditions in Qatar and GCC, this temperature is designed based on 31 °C WB temperature in summer, which result in a 34 °C inlet condenser cooling water temperature. This represents a thermodynamic limitation to reduce the energy consumption of chillers, which lies under the focus of this study. Desiccant cooling is an environmentally attractive alternative to conventional mechanical air-conditioning, especially for air dehumidification purposes. It does not require ozone depleting refrigerants and it can be run off low temperature solar heat or waste heat. The electrical coefficient of performance of desiccant cooling can be above 20, making it over 6 times more efficient than conventional air cooled vapor compression system. This project seeks to develop new processes to reduce air humidity and WB temperature by around 6 °C prior to entering the CT to break the above mentioned thermodynamic limitation. Air dehumidification takes place using liquid to air membrane (3-fluid LAMEEs) for further dehumidification of air. A hybrid solar PV-Thermal system is used for regeneration of both desiccant systems. Lumped and numerical analysis has been conducted using COMSOL Multiphysics software to predict the outlet air temperature and humidity for 3-fluid LAMEEs when used for air cooling and dehumidifying. Results of the numerical and lumped analysis showed that the 3-fluid LAMEE alone can effectively decrease the humidity content of ambient air by up to 40%, while the outlet air temperature can be reduced by 6 °C. Accordingly, the inlet cooling water temperature to the chiller's condenser (outlet water temperature from the CT) can be reduced to 27-28 C, which provides a potential saving of around 25% in energy consumption of the Chiller in district cooling plants.

The consumption of electricity in residential buildings exceeds 20% in Qatar and can go up to 50% in other hot countries like Kuwait. The air-conditioning systems in hot countries like Qatar consumes around 60–80% of the total energy demand in buildings. This triggers researchers and industry experts in the built environment to explore new avenues towards reducing the cooling load on a building and study influential factors to enhance energy efficiency in buildings in such extreme climatic conditions. The carbon foot print of buildings can be reduced by reducing the cooling load through passive building design, using high efficiency equipment and incorporating renewable energy technologies such as solar systems, air source heat pumps, wind generators and ground source heat pumps are few to name that are widely used among many other available renewable technologies. The focus of this research work is on the Passivehouse building design incorporating solar hybrid Photovoltaic Thermal collectors (PV/T) as a source of renewable electricity and solar hot water for domestic use. Two different designs of a residential building for Modern Agro-Industrial Communities in Qatar were considered i.e. Pyramidal Shaped Building and Square Shaped Building. 3D energy models were created for both type of buildings using the IES software (Integrated Environmental Solutions) in virtual environment and thermal analysis was carried out. For the same building type, orientation and structure, two different criteria were applied to the model i.e. Passivehouse design vs. Conventional design. Pyramid shaped buildings are more stable but tend to cost more to construct when compared to traditional buildings. The sloping external walls tend to gain more solar energy and daylight through windows installed on the external walls. This provides an opportunity for solar panels installation on the external walls. The solar gain through external windows can be reduced to a minimum by effective solar shading and the daylight harvesting system can further reduce the artificial lighting gain inside the building. The results show that the passive house design of a building can save more than 70% of the cooling plant load, the as installed plant size and associated infrastructure. This will also considerably reduce the annual operational and maintenance cost of the building with just an extra 15% in construction cost. The cost analysis of passive house in comparison with a conventional house was carried out by QGBC (Qatar Green Building Council). In a nutshell this research work demonstrates how buildings' cooling load and carbon foot print can be reduced by effective solar shading, lower infiltration rates (air tight building design), highly insulated building fabric, natural ventilation, daylight harvesting system (that can help reduce artificial lighting gain inside the building) and heat recovery system.

The paper studies the effectiveness of applying value engineering to concrete mixtures. It was conducted in the State of Qatar on a number of strategic construction projects for the 2022 World Cup projects, in order to generally improve the quality and productivity of ready-mixed concrete used in construction and hydraulic projects. The application of value engineering to such concrete mixtures resulted in the following: Improving the quality of concrete mixtures and increasing the durability of buildings; Optimizing the use of resources, and enhancing sustainability; Reducing the use of cement, thus reducing CO2 emissions which ensure the protection of environment and public health; And Increasing the market share and competitiveness of concrete producers The research shows that applying of value engineering to concrete is an effective way to save around 5% of the total costs of concrete mixtures and, in turn, reducing the costs of construction projects.