Qatar Foundation Annual Research Forum Volume 2010 Issue 1

This work presents a new fully-unstructured meshing scheme for generating simulation meshes, coupled with a novel simulation method for fluid flow models in porous media.

We use unstructured tetrahedral meshing algorithms to generate meshes that rigorously adhere to structural and depositional heterogeneity in geological reservoir models at multiple scales. Geological heterogeneity is represented using numerous surfaces, in contrast with traditional pixel- or grid-based methods. This approach allows the generation of meshes which capture heterogeneity more efficiently and accurately than structured or partially-structured grids.

The flow simulations are performed using a new hybrid discontinuous Galerkin/control volume based method which combines continuous pressure and discontinuous velocities. Our approach rigorously enforces material balance equations while ensuring crucial scalar fields such as pressure and saturation remain positive and bounded.

This research has direct application to aquifer flow systems. We report the results of single-phase flow simulations on unstructured meshes for complex geological systems. These simulations accurately model the spread of groundwater contaminants such as methyl tertiary butyl ether (MTBE) ormetals such as arsenic that behave as tracers in aquifers.

Initially, simulations are run on simple anisotropic geological systems for two-dimensional flow to benchmark against analytical solutions and validate the accuracy of the simulator for simple flow problems. Next, simulations for tracer flow are performed on 3D channelized and fractured reservoir systems to demonstrate the robustness and accuracy of the new grids and simulator in complex reservoir geology.

We present numerical simulations of single-phase flow for a variety of geological systems of increasing complexity, culminating in systems which would be impossible to mesh and solve with structured meshes. This is also a first step towards a more complex multi-phase and multi-component implementation of the novel methods for flow through porous media.

Liquefied natural gas (LNG) carriers have played, and will continue to play, a key role in ocean gas transportation with the increasing demand for energy. Safe operation of LNG carriers requires knowledge of global and local pressures imposed by the sloshing liquid. As LNG carriers are required to operate in different environmental condition, safety is the primary consideration in such operations. LNG carriers are subjected to often significant sloshing loads during their operational life. As it moves across the ocean, the motion of the LNG carriers causes the liquid in the containers to slosh. Liquid sloshing may cause large internal stresses and deformation in the walls of containers, particularly when the external forcing frequencies of the ship are close to the natural sloshing frequencies. This effect is sometimes critical in ship design. A three-dimensional (3D) sloshing problem is analyzed by the linear wave velocity potential theory based on the boundary element method (BEM). When the rectangular tank is undergoing one-dimensional motion, the calculated results are found to be in very good agreement with other published data that assess the accuracy and applicability of the method. Extensive calculation has been made for the tank in two-dimensional (2D) motion. Then random sloshing problem, sloshing in a 3D rectangular container, is further simulated and discussed. In this case, the container filled with liquid is subjected to specified random horizontal oscillations. Both wave elevation and hydrodynamic force are obtained. The spectra of random waves and forces have also been investigated and results are compared between the analytical solutions.

Stony corals are composed of limestone structures formed by the deposits of living organisms. These are tiny animals (polyps) that live in a symbiotic relation with algae. The algae produce the food energy needed by the polyps by photosynthesis. The coral is as such a colony. Numerous colonies on shallow waters where sunrays can reach them form a coral reef. Coral reefs can be extensive, such as the Great Barrier Reef, or can form localized reefs as in Qatar. Coral reefs harbor numerous organisms including sponges, crabs, sea urchins, brittle stars and fish, and exist where environmental conditions are optimal for their flourishing, such as Southeast Asia. Malaysia is reputed as one of the best areas, where 350 coral species are known to occur.

Sea urchins and some fish are ferocious feeders on coral. Extensive feeding may cause the death and bleaching of stony corals. Climate change, in particular high sea temperature, can destroy the coral reef and excessive rains with fresh water seeping to intertidal coral reefs will also cause coral bleaching. Qatar has less than 20 species of stony coral and these are localized in only a few areas. Coastline development, including construction in the sea, is one major cause of loss of natural reefs. Aggressive fishing whether by harpoons or metal traps that are later left behind, destroy the reef. However, the recent bleaching of corals during the last decade and at present, is attributed to two factors: climate change with a rise in sea temperature (1989, 2002, 2010) and oil spills (from the Second Gulf War). Optimum growth temperature for corals is between 20^oC to 23^oC. In June 2010, the sea temperature recorded was 37.8^oC and due to this coral bleaching was observed in local reefs and as well as the death of some fish living in the reef. Bleaching was recorded in 2010 at Halul Island, Ras Rakan, Khereis, Um Alushran and Sherahou.

The results of a cockroach survey in the 14 sub-municipalities of Jeddah province revealed that a total of 3551 cockroaches were caught by 491 of 1433 traps (36.5%), from 128 of 168 houses (76.2%).

Overall, relative density ranged from 8.1 (in Obhour sub-municipality) to 43.2 (in Alaziziah sub-municipality) with an average of 21.1 cockroaches per house. It has been noticed that the population density of the cockroaches is high in the central and southern parts of the province where the sanitation and standard of living are poor.

76.4% of the cockroaches were caught in the kitchens (2712), 15.1% in rooms (537) and 8.5% in the bathrooms (302). Amongst those caught in the kitchens, the stove was found to be the most attractive habitat for the cockroaches (38.2%) followed by the fridge (16.5%), then under the sink (10.2%), in the area of the trash bin (8.1%) and finally under cabinets (3.4%). For those cockroaches caught in the bathrooms, 5.2 % (185) of them were caught under or near washing machines and 3.3 % (117) were under or near the toilet.

Surveys conducted in eight property types in the Jeddah province revealed that 1052 cockroaches were caught by 98 of 120 traps (81.7%). Overall, relative density ranged from 2.9 (in hotels) to 28.1 (in restaurants) with an average of 8.8 cockroaches per property.

All the restaurants (100%) and cafeterias (100%) were found infested by cockroaches, while 93.3% of the hospitals, 86.7% of the hotels, 80% of the groceries 73.3% of the butcheries, 66.7% of the vegetable and fruit shops and 53.3% of the bakeries were found to be infested by cockroaches.

Restaurants had the highest infestation level (40% of the total number of cockroaches trapped in all properties), while hotels had the lowest infestation level (4.1% of the total number of cockroaches trapped in all properties).

Four species of cockroaches were identified from the 14 sub-municipalities, as well as from the eight property types in Jeddah province, namely: the German cockroach (Blattella germanica L.), the American cockroach (Periplaneta americana L.), the brown-banded cockroach (Supella longipalpa F.) and the Oriental cockroach (Blatta orientalis L.) belonging to 4 genera. The German cockroach Blattella germanica was found to be the most predominant species with 98.8% occurrence in dwellings, and 97.7% in properties.

There are two widely used process control techniques for the reduction of process output variability. The first technique is automatic process control (APC) that adjusts the process using information about its current level or deviation from a desired target. The APC actions for process adjustments are achieved by the minimum mean square estimate (MMSE) controller or proportional, integral and derivative (PID) controller which minimize the output deviations from the quality target. The MMSE controller is optimal in terms of minimizing mean squared residual errors when the model and its parameters are exactly known. Whereas the PID controller is very efficient and also robust against non-stationarity due to the fact that it can continuously adjust the process whenever the data is auto-correlated. The second technique is statistical process control (SPC) which utilizes control charts. The goal of SPC for improving quality is to monitor and detect process variability, so that the special causes of the process shifting are investigated. While SPC has been successfully used in industry for identifying and eliminating the assignable cause of variations, APC techniques are widely employed in the continuous process industry to reduce common cause variations. For an improved performance of the process for the industry practitioner, both the monitoring and the adjustments of process are needed to receive the full benefit of each approach. Recently, integration of APC and SPC successfully resulted in the reduction of process output variability and improved process efficiency. In this paper, we integrate SPC and APC for various types of industries including liquefied natural gas (LNG) processes. By applying both the statistical process control and the advanced process control to a process we can dramatically improve the quality of process output. Both statistical process control and automatic process control techniques have been widely applied in industry to detect causes of variability by monitoring the key variables in the process. We investigate both techniques, their integration and methods for shift detection in the process for the monitoring of a process.

Facies tracts, sediment types, stacking patterns, and diagenetic histories of Holocene sabkhas of Qatar provide compelling analogues for the interpretation of ancient, carbonate-evaporite sequences of the Arabian Plate. The use of modern analogues to aid in the interpretation of geological and engineering data is well established in the petroleum industry. Comparison of sabkhas from different physiographic regions of Qatar that formed during the latest Holocene cycle of sea level rises reveals new insights into the characterization of ancient rocks. These observations provide the basis for a revision of the definition of facies tracts described in the geological literature as sabkhas.

This study reports on a country-wide study of the sedimentation history of coastal areas, based on extensive field mapping, geotechnical studies, age dating and geochemistry. Data is integrated in ArcGIS, a relational database. The results are equally valuable in conservation, environmental and geotechnical studies and archaeological research and teaching.

Coastal areas of Qatar are marked by extremely low relief, with the result that high-frequency oscillations in sea level create offsets in facies tracts. Age dating reveals that inland sabkhas are relicts of a high stand in sea level approximately 4000-6000 years ago. These areas are presently subaerially exposed and eroding. Extensive pedogenic modification of marine sediments (burrowing, infiltration, micrite precipitation) creates characteristic textures. Groundwater modification includes extensive precipitation of CaSO4, halite,lime micrite, and dolomite.

The variability observed in Qatar sabkhas alters the way in which a common modern analogue is applied to the interpretation of subsurface data. These observations warrant revision of the definition of a sabkha. We propose that sabkhas are normal, coastal sediments, modified by near-surface groundwater saturated in CaSO4. A sabkha is a diagenetic overprint, not a depositional system. This proposed model helps aid in recognition of ancient sabkhas.

Biodiversity conservation attracts much attention all over the world, highlighted in 2010, the United Nation's International Year of Biodiversity. Effective biodiversity conservation needs basic biological and environmental information, including the behavior and ecology of organisms. The Ethiopian hedgehog (Paraechinus aethiopicus), which is well adapted to the desert environment, is a common species in Qatar and yet little is known concerning their behavior and ecology. We are conducting the first ever research in the Gulf Cooperation Council (GCC) countries on the ecology and behavior of the Ethiopian hedgehog using radio-tracking, supported by the Undergraduate Research Experience Programme (UREP) awarded by the Qatar National Research Fund. The project is still ongoing and we have captured 48 different hedgehogs between April and June 2010, and put radio-tags on 13 (six females and seven males) animals so far. We followed them to collect data for investigating their spatial patterns and habitat preferences during the breeding season (spring and summer) where we found that males’ ranges are larger than those of females. We are currently conducting our fieldwork to investigate these ranges during the non-breeding season (autumn and winter). One of our hypotheses is that males’ ranges during the non-breeding season would be smaller than those during the breeding season whilst there would be no clear difference in females range. We expect that we would be able to collect enough data by December to present the results at the Qatar Foundation Annual Research Forum.

Carbon monoxide (CO) and volatile organic compounds (VOC), such as butadiene and isoprene, are air pollutants emitted by many industrial sources, such as burning of wood and fuel with poor ventilation, and by natural sources including forest fires or volcanic eruptions. It was found that these compounds are also significantly abundant in many industrial processes. Therefore, low-temperature catalytic oxidation of CO and combustion of VOC is one of the most important problems in catalysis, since even small exposures to CO or VOC (ppm) can be lethal. Catalytic oxidation is one effective method of removing CO.

Nanoparticle catalysts are characterized by a large surface area, high dispersion and strong metal-support interaction. It is therefore expected that nanoparticle catalysts would show high catalytic activity for the low temperature oxidation of CO.

Our results demonstrate the application of the vapor phase synthesis to synthesize supported and unsupported nanoparticle catalysts for CO oxidation. The method is based on the laser vaporization/controlled condensation (LVCC) technique of gold (Au) and copper (Cu) nanoparticles supported on a variety of oxide supports such as CeO2, TiO2, CuO and MgO. Our results indicate that Au nanoparticles supported on CeO2 exhibit higher catalytic activity than Au supported on other oxides. This high activity is attributed to the strong interaction of Au with CeO2. The results also indicate that 5 % Au loading on CeO2 has higher activity than 2% Au or 10% Au.

The effect of preparation method on the catalytic activity is investigated. It was found that the catalytic activity for 5%Au/CeO2 prepared by the chemical (deposition-precipitation) method is higher than the catalytic activity of Au/CeO2 prepared by physical (LVCC).

In any combustion system, there are significant amounts of other toxic gases,besides CO, such as nitric oxide, butadiene, and isoprene. We investigated the catalytic activity of the Au/CeO2 nanoparticle catalyst in the presence of 1000 ppm of butadiene and in the presence of 1000 ppm of isoprene. Our results indicate the combustion of butadiene and isoprene to CO2 and H2O, as supported by the mass spectrum and the CO conversion curve.

Finally, the Au/CeO2 nanoparticle catalyst can be an active catalyst for selective CO oxidation at temperatures below 300^oC even in the presence of VOC. Furthermore, this catalyst shows great promise for the low temperature combustion of VOC such as butadiene and isoprene.

Date palms are generally propagated by separating the offshoots produced by individual trees. This method maintains the genetic integrity of date palm cultivars. However, well known date palm cultivars that are grown in different environments show little differences in fruit morphology and quality such as color and sweetness. The objective of the present research project is to analyze the genetic diversity among most common cultivars of Qatari date palms as well as the genetic variation within each cultivar grown in different environments in Qatar. Samples of the five most common date palm cultivars in Qatar; Khalas, Sheshy, Rezezy, Barhee and Khanezy were collected at three locations with different environments Al-Shamal, Al-Khour and Al-Rayan, Qatar. For each cultivar, samples were collected from three trees that showed little variation in their fruit morphology and quality. Genetic similarity or diversity among and within these cultivars was then analyzed using Inter Simple Sequence Repeat (ISSR) markers. A total of 18 ISSR single primers were used to amplify DNA bands using genomic DNA from the date palm samples. All of the primers used have amplified polymorphic bands in the studied cultivars either among the cultivars or within each cultivar in different cultivated environments. The results indicate the existence of genetic variations among the studied cultivars. Moreover, trees of the same cultivar that are grown in different environments show different DNA banding patterns explaining the variation in morphological and quality characters within each cultivar.

Qatar's soil and environment are sources of beneficial bacterial strains and bacterial resources that should be first of all, identified, isolated, studied, used and valorized. In fact, the Qatari environment should be elective for many microbial genetic resources tolerant to high temperature, drought, salinity and hydrocarbon rich soil. Isolating microbial strains having biotechnological applications would be very beneficial not only for Qatar, but also for the Gulf region and other countries in the world. B. thuringiensis is a Gram-positive bacterium which produces, during sporulation, crystalline inclusions containing one or more deltaendotoxins, that are considered as the best biological insecticides as they are harmless for man and animal and act specifically against a wide variety of pathogenic insects, including pests and disease vectors. In this research project, we studied 31 crystal producing Qatari B. thuringiensis isolates, by the investigation of their plasmid patterns, crystal morphology, deltaendotoxin identification by SDS-PAGE, prediction of gene nature by PCR and insecticidal activities. The crystal morphology comparison showed that 22.5 % were spherical, 32.2 % were amorphous, 38.7 % were pyramidal and 6.4 % were bipyramidal. Based on the isolates plasmid patterns, 11 representative strains of the different classes were deeply studied. We used their molecular ribotyping and bioinformatic tools of sequence and BLAST alignment, to confirm that the studied isolates are B. thuringiensis strains. By SDS-PAGE, we showed that the deltaendotoxins produced by the different strains have different molecular weights. The PCR screening of these strains, using oligonucleotides specific for the genes cry1 and cry4, showed the presence of genes cry1A in two strains and allowed us to predict their potential insecticidal activities against lepidopteran larvae. Moreover, we used a B. thuringiensis israelensis in bioassay experiments against local mosquito Culex pipiens larveae and demonstrated the efficacy of such biological bioinsecticides on Qatari mosquitoes. These results are very encouraging and favour the use of B. thuringiensis local strain bioinsecticides for environmentally safe integrated pest management in this region.