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Design and Economic Evaluation of Grid-Connected PV Water Pumping systems for Various Head Locations

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Energy Engineering 2025年第2期122卷 561-576页

作者： moien A.omar Electrical Engineering Department An-Najah National UniversityNablusP400Palestine

This research investigates the design and optimization of a photovoltaic(PV)water pumping system to address seasonal water demands across five locations with varying elevation *** systemdraws water froma deep well with a static water level of 30mand a dynamic level of 50m.s.rving agricultural and livestock *** objective of this study is to accurately size a PV system that balances energy generation and demand while minimizing grid ***,the study presents a comprehensivemethodology to calculate flowrates,pumping power,daily energy consumption,and system ***,the PV system rating,energy output,and economic performance were evaluated using metrics such as discounted payback period(DPP),net present value(NPV),and sensitivity *** results show that a 2.74 kWp PV system is optimal,producing 4767 kWh/year to meet the system.s.annual energy demand of 4686 *** summer,energy demand peaks at 1532.7 kWh,while in winter,it drops to 692.1 ***,flow rates range from 11.71 m3/h at 57 m head to 10.49 m^(3)/h at 70 m head,demonstrating the system.s.adaptability to diverse hydraulic *** analysis reveals that at a 5%interest rate and an electricity price of$0.15/kWh,the NPV is$6981.82 with a DPP of 3.76 ***,a 30%increase in electricity prices improves the NPV to$10,005.18 and shortens the DPP to 2.76 years,whereas a 20%interest rate reduces the NPV to$1038.79 and extends the DPP to 6.08 ***,the annual PV energy generation exceeds total energy demand by 81 kWh,reducing grid dependency and lowering electricity ***,the PV system avoids approximately 3956.6 kg of CO_(2) em.s.ions annually,underscoring its environmental benefits over traditional pumping *** a result,this study highlights the economic and environmental viability of PV-powered water pumping systems,offering actionable insights for sustainable energy solutions in agriculture.

关键词： PV pumping various head grid dependency net present value payback period

Genotypic Profiling and Clinical Impact of Helicobacter pylori Virulence Genes (GLm, HPU, VacA, CagA, and IceA) in Gastroduodenal Diseases among Libyan Patients

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American Journal of molecular Biology 2025年第1期15卷 53-74页

作者： Aya m. Al-Farjany madiha W. El-Awamie Nariman A. Elsharif omar s. Alqabbasi Wail A. Alhawari Fatema I. E. Najem Tarek s. Bader Farag A. Bleiblo Department of Life sciences/microbiology Programme School of Basic Sciences Libyan Academy of Postgraduate Studies Benghazi Libya Department of microbiology Faculty of Science University of Benghazi Benghazi Libya Department of molecular Diagnosis Faculty of Biomedical Sciences University of Benghazi Benghazi Libya Libyan International medical University Benghazi Libya Benghazi Center for Infectious Diseases and Immunology Benghazi Libya Navco Pharmaceuticals Limited Burlington Ontario Canada

Helicobacter pylori infection represents a widespread chronic condition with varying prevalence influenced by race, ethnicity, and geography. The severity of H. pylori-associated diseases is determined by an array of virulence factors. Although extensive studies have been conducted globally, data on the distribution of Helicobacter pylori virulence genes in Libya remain limited, constraining insights into the pathogenicity of local strains and hindering the development of targeted interventions. This study aimed to evaluate the prevalence of H. pylori infection, characterize essential virulence genes [vacA variants (s1/s2, m1/m2), cagA, and iceA1], and examine their association with gastroduodenal diseases among Libyan patients. Gastric biopsies from 144 participants were analyzed using polymerase chain reaction (PCR) assays, and risk factor data were collected via questionnaires. H. pylori was detected in 63.2% of samples by PCR. The vacA gene was present in 84.6% of cases, cagA in 58.2%, and iceA1 in 29.7%. Among vacA variants, s1 allele was m.s. common (53.2%), followed by m1 (42.9%), m2 (37.7%), and s2 (13%) alleles. significant associations were identified between specific virulence genes and the development of gastroduodenal diseases, highlighting their role in pathogenicity. This investigation is one of Libya’s first comprehensive assessments of H. pylori virulence factors, addressing a critical epidemiological gap. The high prevalence of virulence genes suggests their potential as disease biomarkers. These findings contribute to a deeper understanding of H. pylori pathogenicity within the Libyan population and establish a basis for future clinical interventions and public health strategies to manage and prevent H. pylori-associated diseases in Libya and comparable regions.

关键词： H. pylori Virulence Genes Gastroduodenal Diseases Gastric Biopsy PCR

Effect of CuO Addition on the sintering Behavior and Electrical Conductivity of 3Y-TZP

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Journal of materials science & Technology 2007年第1期23卷 131-134页

作者： Ahmed A.Hassan omar Abdelal A. s.m.EL-Hout Dept. of metallurgy Nuclear Research CenterAtomic Energy AuthorityCairoEgypt

Yttria stabilized tetragonal zirconia polycrystals （3Y-TZP） doped with CuO was prepared, to get two compositions, 0.3 and 1 mole fraction CuO, respectively. The dilatometric study of the samples showed sintering to be improved for the samples doped with 0.3 mole fraction CuO, and to be deteriorated for the samples doped with 1 mole fraction CuO. The 1 mole fraction CuO doped 3Y-TZP showed higher tetragonal/monoclinic phase transformation which was accompanied by grain growth. The electrical conductivity decreased with the addition of CuO.

关键词： Y2O3 sintering aids Electrical conductivity Fuel cells

Critical assessment of R410A alternatives for mini-split air conditioners in the Egyptian market

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Energy and Built Environment 2024年第3期5卷 426-445页

作者： omar m.Zaki omar Abdelaziz mechanical Power Engineering Department Faculty of EngineeringCairo UniversityGiza 12613Egypt Department of mechanical Engineering The American University in CairoAUC AvenueNew Cairo 11835Egypt

In this study,the potential implementation of three different low-GWP refrigerants(R32,R452B,and R454B)as replacements for R410A was *** study was performed using a simulation tool developed by the authors called RACHP-Lab,which is a vapor compression system.s.mulation tool developed based on physics-based simulation for typical mini-split air *** simulation study was carried out and validated using experimental performance data of 10 different air conditioning units available in the Egyptian *** units included fixed-speed or variable-speed compressors and operated in cooling or heating ***-in replace-ment with the new refrigerants was carried *** R32,the capacity increased between 4.9%and 13%for cooling cases,and 6.3%and 12.4%for heating ***,COP did not improve in all *** R452B and R454B with direct replacement,the capacity nearly remained the same,with an increase of COP between 1.6%and 8.0%.soft optimization was also conducted on cooling cases where compressor suction superheat,condenser subcooling,and compressor volumetric speed were optimized to maximize COP while maintaining the original capacity of R410A.R32 showed an improvement of COP over R410A between 4.6%and 15.5%,while for R452B and R454B between 2.2%and 13.2%.

关键词： Air conditioner Heat pump Alternative refrigerants Vapor compression cycle modeling

Applications of synchrophasor technologies in power systems

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Journal of modern Power systems and Clean Energy 2019年第2期7卷 211-226页

作者： muhammad Usama UsmAN m. omar FARUQUE Department of Electrical and Computer Engineering Center for Advanced Power Systems Florida State University

synchrophasors are time-synchronized electrical measurements that represent both the magnitude and phase angle of the electrical sinusoids. synchrophasors are measured by fast time-stamped devices called phasor measurement units(Pm.s. to constitute the basis of realtime monitoring and control actions in the electric *** to its enhanced situational awareness capabilities,many applications of Pm.s.are presented in the literature in the past decades. This paper presents a comprehensive summary of synchrophasor technology, its architecture,optimal placement techniques and its applications in electric power transm.s.ion and distribution systems. These applications include wide-area situational awareness and monitoring, state estimation, fault location and protective relaying, islanding detection etc. This review also covers some of the existing challenges in its implementation and its potential applications.

关键词： Phasor measurement unit(PmU) supervisory control and data acquisition(sCADA) synchrophasor technology(sT) Power system

microstructural evolution,dislocation density and tensile properties of Al–6.5si–2.1Cu–0.35mg alloy produced by different casting processes

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Journal of materials science & Technology 2021年第36期95卷 145-157页

作者： s.samat m.Z.omar A.H.Baghdadi I.F.mohamed A.Rajabi A.m.Aziz Department of mechanical and manufacturing Engineering Faculty of Engineering and Built EnvironmentUniversiti Kebangsaan MalaysiaBangiUKM 43600Malaysia

Al–si–Cu–mg foundry alloys are used in casting process ***,their strength properties remain low due to their microstructural characteristics and *** this work,the microstructural characteristics,dislocation densities,and mechanical properties of Al–si–Cu–mg cast alloys prepared through different casting methods were studied *** casting processes,namely,gravity casting(GC),rheocasting(RC),thixoforming(Thixo),and Thixo with heat treatment,were *** GC and RC samples had mainly dendriticα-Al phase microstructures and exhibited coarse si particles and intermetallic compounds in their interdendritic *** contrast,the Thixo and heat-treated Thixo(HT-Thixo)samples exhibited microstructural refinement with uniformly distributedα-Al globules,fine fibrous si particles,and fragmented intermetallic compounds amongα-Al *** accumulation of dislocation densities increased in the Thixo sample as the strain was increased due to plastic ***,the ultimate tensile strength and yield strength of the HT-Thixo sample increased by 87%and 63%,respectively,relative to those of the GC *** cleavage fracture displayed by the GC and RC samples led to brittle ***,the Thixo and HT-Thixo samples presented dimple-based ductile fracture.

关键词： Al–si–Cu–mg alloy Thixoforming microstructure mechanical property Dislocation density

Biochemical studies on malathion resistance, inheritance and association of carboxylesterase activity in brown planthopper, Nilaparvata lugens complex in Peninsular malaysia

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Insect science 2010年第6期17卷 517-526页

作者： m. A. Latif mohd Yosuh omar soon Guan Tan s.s. siraj Abdul Rahim Ismail Department of Crop science Faculty of Agriculture Department of Biology Faculty of Science Department of Cell and molecular Biology Faculty of Biotechnology and Molecular Science Department of Aquaculture Faculty of Agriculture Universiti Putra Malaysia Serdang Selangor Malaysia

Two sympatric populations of brown planthopper （BPH）, one from rice and the other from Leersia hexandra were collected from each of five locations in malaysia. All the tested malathion-resistant individuals of the rice BPH population and F1 generation （cross between malathion-resistant [usually caught on rice] and malathion- susceptible [usually caught on Leersia]） showed high esterase activity, while all malathion- susceptible individuals on L. hexandra showed low esterase activity. In the F2 generation, all the individuals tested against malathion were approximately 75% resistant and 25% susceptible and the inheritance pattern of esterase activity （high and low esterase activity） segregated in the same manner to a 3：1 ratio. This confirms that resistance to malathion is mono-factorial and inheritance pattern ofesterase activity is also linked to malathion resistance. Carboxylesterase or total esterase activity in BPH is inherited in a simple mendelian fashion that is encoded by a single dominant gene. For the total esterase assay, average esterase activity levels in the rice-infesting population ranged from 17.64 to 19.37 nmoles 1-napthol/mg protein while that in the Leersia-infesting population ranged from 5.29 to 6.11 nmoles 1-napthol/mg protein. In terms of esterase activity, the two sympatric Nilaparvata lugens populations separated into two distinct groups. Results based on the tube color intensity test showed 96% and 98% resistant and susceptible individuals were present in the rice- and Leersia-infesting populations, respectively. In a filter paper test, the rice-infesting population had 94% with high esterase activity while the Leersia-infesting population had 96% with low esterase activity.

关键词： brown planthopper carboxylesterase assay inheritance study insecticide resistance rice

Influence of Cu content on microstructure and mechanical properties of thixoformed Al-si-Cu-mg alloys

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Transactions of Nonferrous metals society of China 2015年第11期25卷 3523-3538页

作者： m.s.sALLEH m.Z.omar Department of mechanical and materials Engineering Faculty of Engineering and Built Environment Universiti Kebangsaan Malaysia Department of manufacturing Process Faculty of Manufacturing Engineering Universiti Teknikal Malaysia Melaka

The effects of Cu content on the microstructure and mechanical properties of thixoformed Al-6si-xCu-0.3mg(x= 3,4,5and 6,m.s. fraction,%) alloys were *** samples were thixoformed at 50%liquid content and several of the samples were treated with the T6 heat *** samples were then examined by optical microscopy(Om),scanning electron microscopy(sEm),energy dispersive X-ray(EDX) spectroscopy and X-ray diffraction(XRD) analysis,as well as hardness and tensile *** results show that the cooling slope casting and thixoforming process promote the formation of very fine and well distributed intermetallic compounds in the aluminium matrix and the mechanical properties of the alloys increase considerably compared with the permanent mould *** results also reveal that as the Cu content in the alloy increases,the hardness and tensile strength of the thixoformed alloys also *** ultimate tensile strength,yield strength and elongation to fracture of the thixoformed heat-treated Al-6si-3Cu-0.3mg alloy are 298 mPa,201 mPa and 4.5%,respectively,whereas the values of the thixoformed heat-treated alloy with high Cu content(6%) are 361 mPa,274 mPa and 1.1%,*** fracture of the thixoformed Al-6si-3Cu-0.3mg alloy shows a dimple rupture,whereas in the alloy that contains the highest Cu content(6%),a cleavage fracture is observed.

关键词： Al-si-Cu-mg alloy Cu content thixoforming T6 heat treatment mechanical properties

Geochem.s.ry, mineralogy, and radioactivity of the Abu Furad Area, Central Eastern Desert, Egypt

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Acta Geochimica 2019年第2期38卷 307-326页

作者： A.m.El mezayen E.K.Abu Zeid W.s.Hosny m.G.El-Feky s.m.omar s.A.Taalab Geology Department Faculty of Science Al Azhar University Nuclear material Authority Cairo Egypt

Abu Furad is in the Central Eastern Desert,Egypt. It comprises metasediments, metavolcanics,metagabbros, syn-to late-orogenic granites, and post-orogenic granites, in addition to numerous dykes and veins of different shapes and composition invading all the older rocks cropping out in the study area. Field, petrographic,mineralogical, and chemical investigations led to the classification of Abu Furad granites as quartz diorite, tonalite,granodiorite, and *** oxide and trace element data revealed that the syn-to late-orogenic granites and post-orogenic granites are peraluminous. syn-to lateorogenic granites originated from calc-alkaline volcanic arc–related magma; while the post-orogenic granites(syenogranite) are highly fractionated, calc-alkaline granite from a within plate regime. Radiometrically, the studied quartz diorite, tonalite, and granodiorite had lower uranium and thorium contents and higher eU/eTh ratios than the syenogranites. This may indicate that the syn-to late-orogenic rocks originated from.s.urces depleted in these elements. The average e Th/eU ratio of syenogranites was higher than that of average continental crust, suggesting that the syenogranites are relatively depleted in U. The studied altered syenogranites were strongly enriched in U and Th compared to the Earth's crust. On the other hand, the average of e U in pegmatites is lower than the global average for uraniferous pegmatites. The m.s. recorded accessory minerals in the altered syenogranites were thorite, fergusonite, samarskite, columbite, zircon, monazite, xenotime,apatite, fluorite, sphene, atacamite, and malachite, in addition to chromium and nickel inclusions.

关键词： Hydrothermal alterations major oxide and trace elements Radiometry mineralogy Geochem.s.ry Altered syenogranites Egypt