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Seismic response of skewed RC box-girder bridges

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Earthquake Engineering and Engineering Vibration 2008年第4期7卷 415-426页

作者： Ahmed abdel-Mohti Gokhan Pekcan Civil and Environmental Engineering Department University of Nevada Reno

It is critical to ensure the functionality of highway bridges after earthquakes to provide access to important facilities. Since the 1971 San Fernando earthquake, there has been a better understanding of the seismic performance of bridges. Nonetheless, there are no detailed guidelines addressing the performance of skewed highway bridges. Several parameters affect the response of skewed highway bridges under both service and seismic loads which makes their behavior complex. Therefore, there is a need for more research to study the effect of skew angle and other related factors on the performance of highway bridges. This paper examines the seismic performance of a three-span continuous concrete box girder bridge with skew angles from 0 to 60 degrees, analytically. Finite element （FE） and simplified beam-stick （BS） models of the bridge were developed using SAP2000. Different types of analysis were considered on both models such as： nonlinear static pushover, and linear and nonlinear time history analyses. A comparison was conducted between FE and BS, different skew angles, abutment support conditions, and time history and pushover analysis. It is shown that the BS model has the capability to capture the coupling due to skew and the significant modes for moderate skew angles. Boundary conditions and pushover load profile are determined to have a major effect on pushover analysis. Pushover analysis may be used to predict the maximum deformation and hinge formation adequately.

关键词： skew bridge seismic response pushover analysis time history analysis modeling

A poroelastic numerical model for simulation of hydraulic fracture propagation:Application to Upper Safa formation-Western Desert-Egypt

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Petroleum Research 2020年第1期5卷 39-51页

作者： Reda abdel Azim Petroleum Engineering Department American University of KurdistanDohoukIraq

The hydraulic fracturing in tight sand formations has a significant importance in improving its production *** this study,a poroelastic numerical model is presented in order to study the reservoirs and rock mechanical properties that affect the propagation of the hydraulic *** poroelastic model simulate fully coupled fluid flow,pressures and stress changes by using finite element *** results show that the formation permeability and fracture toughness are key parameters in the design of hydraulic fracture treatment.A case study applied in Upper Safa formation in a well-located western desert *** formation is very tight with permeability of 0.1md and the objective here is to optimize the design procedures for hydraulic fracture *** results show that the formation needs to be pumped for about 5min to produce hydraulic fracture length of 182 *** addition,the total pumping time(30 min)is vital to produce the desired total fracture length of 1000 ft.

关键词： Fracture propagation Finite element Upper Safa formation Poroelastic Leak off model

Particle size effect on ammonium perchlorate decomposition kinetics

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航空动力学报 2012年第5期27卷 1179-1184页

作者： abdel-Wareth W XU Xu School of Astronautics Beijing University of Aeronautics and AstonauticeBeijing 100191China

The decomposition kinetic parameters of ammonium perchlorate(AP) having different grain size(10-390 μ m) were investigated through simultaneous DSC / TGA(differential scanning calorimetry / thermal gravimetric analysis) analyzer in a dynamic nitrogen atmosphere under heating rate of 40K / *** kinetic parameters such as activation energy and pre-exponential factor were determined by the modified isoconversional *** Brurzauer-Emmett-Teller(BET)-method was applied to measure AP specific surface *** results show that the higher the AP particle size the lower the determined kinetic parameters and are matched with some important literatures.

关键词： ammonium perchlorate particle size specific surface area thermal decomposition thermogravimetry

Impact of wastewater reuse on cobalt status in Egyptian environment

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Journal of Environmental Sciences 2003年第3期15卷 388-395页

作者： M.F. abdel-Sabour Soil and Water Research Department Nuclear Research Center Atomic Energy Authority

Cobalt is used in the manufacture of alloys, catalysts in the petroleum industry, catalytic converters, and paint pigments. Thus the potential for Co releases into the environment is highly increased. Use of waste sludges and sewage effluent to fertilize and irrigate soils has also increased soil Co concentrations. Total cobalt contents of alluvial delta soil of Egypt show considerable variation ranging from 13.1 to 64.7 ppm. The impact of either wastewater irrigation or industrial activities on soil total Co was obvious due to accumulation of organic matter and solid waste in the surface soil samples. Food crops and vegetables should not be grown on soil highly contaminated by Co. It is noteworthy that the delayed neutron activation analysis(DNAA) technique could be used successfully for total Co determination due to its high sensitivity. It is quit clearly that dust samples of Cairo City contains higher Co level, as compared to Suez Canal Region(Ismailia, Port Said and El-Suez cities). The high values in Cairo City may be due to the existence of industries around the city and the intensive traffic. To minimize Co environmental hazards, waste effluents should be treated on site. Thus, levels of potentially toxic Co needs to be continuously monitored and should be removed during several treatment processes before the disposal of these wastes.

关键词： cobalt environment Egypt

A hybrid simulation approach to evaluate stimulation micro-seismic events and production potential of fractured geothermal reservoirs

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Petroleum Research 2020年第2期5卷 131-143页

作者： Reda abdel Azim Petroleum Engineering Department American University of Kurdistan Zakho Rd.99641DohoukIraq

This study presents an integrated approach to simulate fluid flow and to predict the micro seismic eventsduring stimulation and circulation of cold water over a longer term in geothermal reservoirs. The integrated approach based on new three dimensional fully coupled thermo-poroelastic numerical model forevaluation of energy recoverable. In the presented approach, the fracture aperture due to fractureslippage is calculated by shear and dilation. The shear slippage is controlled by the concept of shearfailure using linear Mohr-Coulomb criterion. The numerical model is validated against an analytical Oda’smodel for permeability tensor calculation and against an analytical solution for thermo-poroelasticmodel. The heat transfer between the rock and fluid is modelled by using the conductive heat transferwithin the reservoir rock and convective heat transfer in discrete fractures. The thermal stress changesare included in the model to be studied by using roughness induced shear displacement principle in aporo-thermo-elastic environment. The fracture aperture changes are estimated by using an analyticalmodel based on the distributed dislocation technique. The roughness of fracture surfaces is used in thecalculation of residual fracture aperture. The presented approach is used to study the potential ofpermeability enhancement for Habanero geothermal reservoir at a depth of 3600 m. The result show thatthe increasing in tensile effective stress tend to increase the fracture aperture within the zone of *** increasing in fracture aperture led to significant changes in pressure distribution (decrease inimpedance) and hence, increase in the flow rate.

关键词： Fractured reservoirs Finite element Permeability tensor Fracture aperture Tensile stress Fractal density and dimension

Omphalocele Diagnosis Problem in Rural Environment

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Surgical Science 2024年第8期15卷 501-506页

作者： Kanté Sékou Diallo Siaka Touré Cheick Amed Sékou Ousmane I. Touré Coulibaly Ibrahim Traoré Drissa Bengaly Brehima Sanogo Soulemane Togola Birama Ouattara Drissa Saye Jack Ongoïba Nouhoum Koumaré abdel Karim Service de Chirurgie B CHU Point G Bamako Mali Facult de Mdecine de lUSTTB Bamako Mali

Introduction: An omphalocele is a congenital malformation due to a failure of closure of the umbilical ring with exteriorization of the abdominal viscera covered by the translucent and avascular amniotic membrane. We report a case of giant omphalocele unrecognized at birth followed by a review of the literature. Observation: This was a 4-year-old girl admitted to the department for umbilical swelling that had been present since birth. Clinical and paraclinical examinations made it possible to objectivize a post-omphalocele hernia with hepatic content plus ectopic accession of the left ureter, the surgical procedure consisted of reintroducing the liver associated with a cure of the hernia + ureterovesical reimplantation. Conclusion: Omphalocele is a congenital malformation, antenatal diagnosis is possible during morphological ultrasound from the 12th week.

关键词： Omphalocele Ectopic Left Ureter

Blood exosomes as a tool for monitoring treatment efficacy and progression of neurodegenerative diseases

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Neural Regeneration Research 2019年第1期14卷 72-74页

作者： Hanin abdel-Haq National Center for Drug Research and Evaluation Istituto Superiore di Sanità

Alzheimer’s disease,Parkinson’s disease,Huntington’s disease,amyotrophic lateral sclerosis,and prion disease are representative neurodegenerative diseases that share common sub-cellular features,the most obvious of which is a strong association with the accumulation of misfolded,aggregated,and insoluble forms of proteins in the brain,as evidenced in post-mortem brain tissues of *** of neurodegenerative diseases is often

关键词：疾病治疗功效 cellular 工具 prion 蛋白质大脑

Theoretical Approach to Change Blast Furnace Regime With Natural Gas Injection

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Journal of Iron and Steel Research International 2013年第9期20卷 40-46页

作者： K S abdel Halim Central Metallurgical Research and Development Institute(CMRDI)

The operation of blast furnace using natural gas and oxygen enriched blast （composite blast technology） is considered in many countries to be standard operation for a modern blast furnace particularly in certain countries with cheap and stable supply of natural gas. The theoretical flame temperature （TFT） of combustion and the degree of di-rect reduction of iron oxides （rd） are considered as the main controlling parameters of composite blast technology. The calculated values of these parameters are mainly dependent on the amount of air blast consumption. This amount of air blast is measured before entering into blast stoves, Actually, some of air blast is lost through valves of air stoves. Consequently, the real volume of air blast in the furnace is less than the recorded value by amounts of 5%-15% which is not considered in the estimation of rd and TFT. The purpose is to analyze the different methods for es-timation of air blast inside the blast furnaces and develop a theoretical model to calculate air blast eonsumption with high accuracy. Based on the calculation of air blast consumption, a complete roadmap is demonstrated to change the operation regime parameters of blast furnaces working on composite blast technology.

关键词： composite blast technique natural gas blast consumption theoretical flame temperature direct reduc-tion degree iron oxide

Practical approach to linear endoscopic ultrasound examination of the gallbladder

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World Journal of Radiology 2024年第6期16卷 184-195页

作者： Hussein Hassan Okasha Eyad Gadour Hassan Atalla Omar AbdAllah abdel-Hameed Reem Ezzat Ahmed Elsayed Alzamzamy Elsayed Ghoneem Rasha Ahmad Matar Zeinab Hassan Bogdan Miutescu Ayman Qawasmi Katarzyna M Pawlak Ahmed Elmeligui Department of Internal Medicine Division of Gastroenterology and HepatologyKasr Al-Aini School of MedicineCairo UniversityCairo 11562Egypt Department of Gastroenterology and Hepatology King Abdulaziz Hospital-National GuardAhsa 31982Saudi Arabia Department of Medicine School of MedicineZamzam University CollegeKhartoum 11113Sudan Department of Internal Medicine Hepatology and Gastroenterology UnitFaculty of MedicineMansoura UniversityMansoura 35516Egypt Department of Internal Medicine Faculty of MedicineAssiut UniversityAssiut 71511Egypt Department of Gastroenterology and Heptology Maadi Armed Forces Medical ComplexMilitary Medical AcademyCairo 11728Egypt Department of Gastroenterology and Advance Endoscopy Sultant Qaboos Comprehensive Cancer Care and Research CentreMuscat 0961Oman Department of Internal Medicine Stockport Hospitals NHS Foundation TrustManchester SK27JEUnited Kingdom Department of Gastroenterology and Hepatology Victor Babes University of Medicine and PharmacyTimisoara 300041Romania Advanced Regional Research Centre in Gastroenterology and Hepatology Victor Babes University of Medicine and PharmacyTimisoara 30041Romania Department of Gastroenterology Al-Makassed Islamic Charitable Society HospitalCairo 11124Egypt Division of Gastroenterology St.Michael’s HospitalUniversity of TorontoToronto M5B 1W8Canada Department of Gastroenterology Southend University HospitalEssex SS26XTUnited Kingdom

The gallbladder(GB)is a susceptible organ,prone to various pathologies that can be identified using different imaging *** ultrasound(TUS)is typically the initial diagnostic method due to its numerous well-established ***,in cases of uncertainty or when a definitive diagnosis cannot be established,computed tomography(CT)or magnetic resonance imaging may be employed to provide more detailed ***,CT scans may sometimes offer inadequate spatial resolution,which can limit the differentiation of GB lesions,particularly when smaller yet clinically relevant abnormalities are ***,endoscopic ultrasound(EUS)provides higher frequency compared to TUS,superior spatial resolution,and the option for contrast-enhanced harmonic imaging,enabling a more comprehensive ***,EUS can serve as a supplementary tool when conventional imaging methods are *** review will describe the standard EUS examination of the GB,focusing on its endosonographic characteristics in various GB path-ologies.

关键词： Endoscopic ultrasound Linear endoscopic ultrasound Gallbladder anatomy Gallbladder pathologies Therapeutic endoscopic ultrasound