Mature oil reservoirs surrounded with strong edge and bottom water drive aquifers experience pressure depletion and water coning/cresting. This laboratory research investigated the effects of bottom water drive and gas breakthrough on immiscible CO2-Assisted Gravity Drainage (CO2-AGD), focusing on substantial bottom water drive. The CO2-AGD method vertically separates the injected CO2 to formulate a gas cap and Oil. Visual experimental evaluation of CO2-AGD process performance was performed using a Hele-Shaw model. Water-wet sand was used for the experiments. The gas used for injection was pure CO2, and the “oleic” phase was n-decane with a negative spreading coefficient. The aqueous phase was deionized water. To evaluate the feasibility of the CO2-AGD process without any bottom water drives, it was first used. The experimental results demonstrated that existence of bottom water drive affected oil recoveries due to pressure support. Oil recovery before gas breakthrough increases proportionally with bottom water drive intensity. The gas breakthrough time recoveries for CO2-AGD1, CO2-AGD2, and CO2-AGD3 runs were 38.68%, 50.70%, and 60.85% of OOIP. The pressure gradient along the physical model decreases as bottom water drive intensity increases. The CO2-AGD approach delayed gas breakout by 72 min. As aquifer strength increases, gas breakthrough is delayed. In the three CO2-AGD runs and after breakthrough occurrence, the injector-producer pressure difference decreased due to the residual heads of oil and water columns above the horizontal well. As long as oil and water exist in the model, the pressure differential will not be zero, and the relative permeability and capillary trapping also control this phenomenon. Finally, it was demonstrated that there is a direct correlation between the strength of the aquifer and the oil recovery factor. The strength of the aquifer positively affects the oil recovery at breakthrough and the ultimate oil recovery.
The gypseous soil may be one of the problems that face the engineers especially when it used as a foundation for hydraulic structures, roads, and other structures. Gypseous soil is strong soil and has good properties when it is dry, but the problem arises when building hydraulic installations or heavy buildings on this soil after wetting the water to the soil by raising the water table level from any source or from rainfall which leads to dissolve the gypsum content. Cement-stabilized soil has been successfully used as a facing or lining for earth channel, highway embankments and drainage ditches to reduce the risk of erosion and collapsibility of soil. This study is deliberate the treatment of gypseous soil by using a mixture
... Show MoreThe objective of this study was to evaluate a natural bio-insecticide manufacturing from Eucalyptus sp. volatile oil. The use of Eucalyptus sp. against the Backswimmer insect Anisops sardea Herrich-Schaeffer, 1849 predatory of larvae of common carp fish, Cyprinus carpio L., in artificial closed ponds in Babylon province represented a new idea in Iraq. The volatile oil of the Eucalyptus sp. was extracted by hot water method using the Clevenger, three concentrations of 250000, 450000 and 650000 ppm with benzyl benzoate as a stabilizer were used, which has a boiling point of 324OC (slow evaporation) at field experiment.The results of field and laboratory experiments of the extracted volatile oil in different concentrations, showed that
... Show MoreBackground: The stethoscope is a tool that doctors use daily in the examination of patients and it can take part in the transmission of health care-associated infections. In a single day it may come in direct contact with multiple patients and the intra hospital environment may be contaminated by various type of bacteria and possibly transmit to others.
Objective:- The study was to know the attitude and knowledge about the stethoscope hygiene behavior among physicians and to determine the types of bacterial agents that can contaminate stethoscopes.
Type of the study: The study was a cross-sectional study
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... Show MoreKE Sharquie, AA Noaimi, EA Al-Janabi, Our Dermatology Online, 2014 - Cited by 11
Increasing the power conversion efficiency (PCE) of silicon solar cells by improving their junction properties or minimizing light reflection losses remains a major challenge. Extensive studies were carried out in order to develop an effective antireflection coating for monocrystalline solar cells. Here we report on the preparation of a nanostructured cerium oxide thin film by pulsed laser deposition (PLD) as an antireflection coating for silicon solar cell. The structural, optical, and electrical properties of a cerium oxide nanostructure film are investigated as a function of the number of laser pulses. The X-ray diffraction results reveal that the deposited cerium oxide films are crystalline in nature and have a cubic fluorite. The field
... Show MoreFabrication of porous clay refractory insulating specimens from Iraqi kaolin with different percentage of Expanded Polystyrene (EPS) waste crumbs additions were investigated. After mixing and forming by hand molding, the specimens was dried and fired at 1300 oC. The structural, physical, mechanical and thermal properties of the refractory insulating products were measured. Maximum addition of EPS (1.25 wt%) lead to reduce the linear shrinkage to less than 1.7% and increased apparent porosity up to 50 %. As well as, the density, Modulus of rupture and thermal conductivity were reduced to 1.39 g/cm3, 4.1 MPa and 0.21 W/m.K, respectively. The final outcome, addition of EPS showed good results in the formation of pores without distorting the
... Show MoreFlexure members such as reinforced concrete (RC) simply supported beams subjected to two-point loading were analyzed numerically. The Extended Finite Element Method (XFEM) was employed for the treatment the non-smooth h behaviour such as discontinuities and singularities. This method is a powerful technique used for the analysis of the fracture process and crack propagation in concrete. Concrete is a heterogeneous material that consists of coarse aggregate, cement mortar and air voids distributed in the cement paste. Numerical modeling of concrete comprises a two-scale model, using mesoscale and macroscale numerical models. The effectiveness and validity of the Meso-Scale Approach (MSA) in modeling of the reinforced concrete beams w
... Show MoreData-driven models perform poorly on part-of-speech tagging problems with the square Hmong language, a low-resource corpus. This paper designs a weight evaluation function to reduce the influence of unknown words. It proposes an improved harmony search algorithm utilizing the roulette and local evaluation strategies for handling the square Hmong part-of-speech tagging problem. The experiment shows that the average accuracy of the proposed model is 6%, 8% more than HMM and BiLSTM-CRF models, respectively. Meanwhile, the average F1 of the proposed model is also 6%, 3% more than HMM and BiLSTM-CRF models, respectively.