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Acta Geologica Sinica(English Edition) 2021年第5期95卷 1568-1582页

作者： mohamed a.ali Ahmed E.ABDEL GAWAD mohamed M.GHONEIM Nuclear Materials Authority 530 El-MaadiCairoEgypt

The garnet muscovite granitic pegmatite of Um Solimate,in southern Egypt,represents a promising asset for strategic and economic metals,especially Bi-Ni-Ag-Nb-Ta as well as U and *** ore bodies occur as large masses,pockets and/or veins of very coarse-grained pegmatites,which consist mainly of K-feldspar,quartz and albite with subordinate muscovite,garnet,and *** data revealed that e U-and e Th-contents of the pegmatites reach up to 39 ppm and 82 ppm,*** studied pegmatites are enriched in primary U and Th minerals(uraninite,coffinite,thorianite and uranothorite)as well as Hf-rich zircon and monazite,which give rise to anomalous radioactive ***-tantalium-bearing minerals(***,microlite and uranopyrochlore),xenotime,barite,galena,fluorite,and apatite are ubiquitous,and,consequently,the studied pegmatites belong tothe Niobium-Yttrium-Fluorine-type(NYF)*** noble metal mineralization includes argentite(Ag_(2)S),native Ni and Bi as well as bismite and *** addition,beryl and tourmaline are observed in pegmatites near the contact with metasediments and ultramafic *** observed compositional variations of Ta/(Ta+Nb)and Mn/(Mn+Fe)ratios in columbite(0.08-0.45 and 0.11-0.57,respectively)and Hf contents in zircon(3.54-6.46 wt%)may reflectan extreme degree of magmatic fractionation leading to formation of the pegmatite orebody.

关键词： radioactivity rare-metal mineralization pegmatites U/Th-bearing minerals Um Solimate Egypt

Mineralogy and radioactivity of pegmatites from South Wadi Khuda area,Eastern Desert,Egypt

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Chinese Journal Of Geochemistry 2010年第4期29卷 343-354页

作者： mohamed F.Raslan mohamed a.ali mohamed G.El-Feky Nuclear Materials Authority P.O.Box 530El MaadiCairoEgypt

Radioactive minerals in pegmatites associated with granitic rocks are commonly encountered in the south of the Wadi Khuda area and found as dyke-like and small *** are observed within garnet-muscovite granites near the contact with older *** surveys indicated that the studied pegmatites vary in dimensions ranging from 2 to 10 m in width and from 10 to 500 m in *** are composed mainly of intergrowth of milky quartz,reddish-pink K-feldspar and plagioclase together with small pockets of *** radiometric measurements indicated that radioactivity in pegmatites is more than twice that of their enclosing country *** measurements revealed that the average contents of U and Th increase gradually from rocks of dioritic to granodioritic composition(1.5×10-6 U and 4.3×10-6 Th) and increase significantly in biotite granites(5.8×10-6 U and 15.2×10-6 Th) but drastically decrease in muscovite granites(2.2×10-6 U and 5.6×10-6 Th).The average contents of U and Th of anomalous pegmatites are 95.3×10-6 and 116.9×10-6,respectively,indicating their uraniferous *** the south of the Wadi Khuda area,pegmatites are low in average Th/U(1.4) and high in average U/K(35.6),which suggests that uranium concentrating processes did not affect the pegmatites,indicating poor *** investigations of the studied pegmatites revealed the presence of secondary uranium minerals(kasolite and autunite),in addition to zircon,thorite,apatite,garnet and *** and secondary radioactive mineralizations indicated that the mineralization is not only magmatic,but also *** microprobe analyses showed distinct cryptic chemical zoning within thorite where UO2 decreases from core to *** feature in thorite is sporadic,suggesting non-uniform redistributions of UO2 within thorite during magmatic processes.

关键词：放射性核素伟晶岩矿物学黑云母花岗岩平均含量沙漠埃及电子探针分析

Enhancing Renewable Energy Integration:A Gaussian-Bare-Bones Levy Cheetah Optimization Approach to Optimal Power Flow in Electrical Networks

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1339-1370页

作者： ali S.Alghamdi mohamed A.Zohdy Saad Aldoihi Department of Electrical Engineering College of EngineeringMajmaah UniversityAl-Majmaah11952Saudi Arabia Electrical and Computer Engineering Department Oakland UniversityRochesterMI48309USA Institute of Earth and Space Science King Abdulaziz City for Science and Technology(KACST)Riyadh11442Saudi Arabia Computer Science and Systems Engineering Institute Polytechnique de ParisPalaiseau CedexFrance

In the contemporary era,the global expansion of electrical grids is propelled by various renewable energy sources(RESs).Efficient integration of stochastic RESs and optimal power flow(OPF)management are critical for network *** study introduces an innovative solution,the Gaussian Bare-Bones Levy Cheetah Optimizer(GBBLCO),addressing OPF challenges in power generation systems with stochastic *** primary objective is to minimize the total operating costs of RESs,considering four functions:overall operating costs,voltage deviation management,emissions reduction,voltage stability index(VSI)and power loss ***,a carbon tax is included in the objective function to reduce carbon *** scrutiny,using modified IEEE 30-bus and IEEE 118-bus systems,validates GBBLCO’s superior performance in achieving optimal *** results demonstrate GBBLCO’s efficacy in six optimization scenarios:total cost with valve point effects,total cost with emission and carbon tax,total cost with prohibited operating zones,active power loss optimization,voltage deviation optimization and enhancing voltage stability index(VSI).GBBLCO outperforms conventional techniques in each scenario,showcasing rapid convergence and superior solution ***,GBBLCO navigates complexities introduced by valve point effects,adapts to environmental constraints,optimizes costs while considering prohibited operating zones,minimizes active power losses,and optimizes voltage deviation by enhancing the voltage stability index(VSI)*** research significantly contributes to advancing OPF,emphasizing GBBLCO’s improved global search capabilities and ability to address challenges related to local *** emerges as a versatile and robust optimization tool for diverse challenges in power systems,offering a promising solution for the evolving needs of renewable energy-integrated power grids.

关键词： Renewable energy integration optimal power flow stochastic renewable energy sources gaussian-bare-bones levy cheetah optimizer electrical network optimization carbon tax optimization

Model Predictive Current Control for Low-Cost Shunt Active Power Filter

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1589-1598页

作者： ali A.Abdel-Aziz mohamed A.Elgenedy Barry W.Williams the Electronic and Electrical Engineering Department Strathclyde UniversityGlasgowG11XQUK School of Computing Engineering and the Built Environment(SCEBE)Glasgow Caledonian UniversityGlasgowG40BAUK

Performance of a three-phase shunt active power filter(SAPF)relies on the capability of the controller to track the reference ***,designing an accurate current controller is crucial to guarantee satisfactory SAPF *** paper presents a model predictive current controller(MPCC)for a low-cost,four-switch,shunt active power filter for power quality improvement.A four-switch,B4,converter topology is adopted as an SAPF,hence offering a simple,robust,and low-cost *** addition,to further reduce overall cost,only two interfacing filter inductors,instead of three,are used to eliminate switching current *** proposed SAPF model MPCC is detailed for implementation,where simulation and experimental results validate effectiveness of the proposed control algorithm showing a 20%improvement in total harmonic distortion compared with a conventional hysteresis band current controller.

关键词： Four-switch converter harmonic distortion model predictive current control power quality shunt active power filter

Effect of reaction and post-treatment conditions on physico-chemical properties of magnetic iron oxide nano-particles Author links open overlay panel

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Particuology 2024年第8期91卷 155-167页

作者： Masome Moeni mohamed Edokali Matthew Rogers Oscar Cespedes Louey Tliba Tamseela Habib Robert Menzel ali Hassanpour School of Chemical and Process Engineering Faculty of Engineering and Physical ScienceUniversity of LeedsLeedsLS29JTUK School of Physics and Astronomy Faculty of Engineering and Physical ScienceUniversity of LeedsLeedsLS29JTUK Mechanical Engineering Department University of Engineering&TechnologyLahorePakistan School of Chemistry Faculty of Engineering and Physical ScienceUniversity of LeedsLeedsLS29JTUK

Poor stability and dispersibility,as well as aggregation are considered as major challenges in clinical application of iron oxide nanoparticles(IONPs).Several studies have shown that the synthesis parameters and post-synthesis treatments e.g.,drying methods,have the capability to improve the particles'***,we investigate the combined effect of synthesis and post-treatment parameters on the particle size,stability and magnetism of ***(Fe_(3)O_(4))NPs were prepared via co-precipitation and post-treated using different methods,i.e.(i)freeze dried at-53℃,0.133 mbar for 48 h(liquid nitrogen frozen(LFD)and freezer frozen(FFD)),(ii)vacuum oven dried(VOD)at 60℃for 24 h,and(iii)kept wet colloidal(WET),dispersed in deionized *** Fe_(3)O_(4)NPs’chemical functional groups,size,shape,crystallinity,stability,aggregation,porosity,and magnetic properties were further analysed using different characterisation *** results showed that,while the WET sample had the best stability and significantly less aggregation at different temperatures,amongst post-treated Fe_(3)O_(4)NPs,LFD sample exhibited the best stability(up to 37℃),dispersion and smallest polydispersity ***,all dried NPs had superparamagnetic characteristics,while,LFD Fe_(3)O_(4)NPs had better magnetic properties and stability than other drying methods.

关键词： Iron oxide nanoparticles Co-precipitation Stability Aggregation Magnetic properties

Primary gastroduodenal tuberculosis presenting as gastric outlet obstruction:A case report and review of literature

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World Journal of Clinical Cases 2024年第8期12卷 1536-1543页

作者： Abdihamid mohamed ali Yahye Garad mohamed Abdirahman Ahmed Mohamud Abdulkadir Nor mohamed mohamed Rage Ahmed Ismail Mohamud Abdullahi Tuba Saydam Department of General Surgery Mogadishu Somali Turkey Recep Tayyip Erdogan Training and Research HospitalMogadishu 2526Somalia Department of Radiology Mogadishu Somali TurkeyTraining and Research HospitalMogadishu 2526Somalia Department of Pathology Mogadishu Somali Turkey Recep Tayyip Erdogan Training and Research HospitalMogadishu 2526Somalia

BACKGROUND Mycobacterium tuberculosis(TB)is the causative agent of TB,a chronic granulo-matous *** disease is prevalent in low-income countries,posing a significant global health *** TB is one of the three *** disease can mimic other intra-abdominal conditions,leading to delayed diagnosis owing to the absence of specific *** gastric outlet obs-truction(GOO)remains a frequent complication,its incidence has declined with the advent of proton pump inhibitors and Helicobacter pylori eradication *** TB can cause upper gastrointestinal hemorrhage,obstruction,and malignancy-like *** SUMMARY A 23-year-old male presented with recurrent epigastric pain,distension,nausea,vomiting,and weight loss,prompting a referral to a gastroenterologist *** examination revealed distorted gastric mucosa and signs of chronic ***,treatment was interrupted,possibly owing to vomiting or comorbidities such as human immunodeficiency virus infection or *** surgical intervention revealed a dilated stomach and diffuse thickening of the duodenal *** revealed gastric wall effacement with *** Primary gastric TB is rare,frequently leading to *** its rarity,suspicions should be promptly raised when encountering relevant symptoms,often requiring surgical intervention for diagnosis and treatment.

关键词： Tuberculosis Gastrointestinal tuberculosis Gastric outlet obstruction Gastroduodenal tuberculosis Case report

Designing single atom catalysts for exceptional electrochemical CO_(2) reduction

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Chinese Journal of Structural Chemistry 2024年第1期43卷 3-5页

作者： Muhammad Humayun mohamed Bououdina Abbas Khan Sajjad ali Chundong Wang Energy Water and Environment LabCollege of Humanities and SciencesPrince Sultan UniversityRiyadh11586Saudi Arabia School of Integrated Circuits Wuhan National Laboratory for OptoelectronicsHuazhong University of Science and TechnologyWuhan430074PR China Department of Chemistry Abdul Wali Khan University MardanMardan23200Pakistan

The release of anthropogenic CO_(2)emissions into the atmosphere has significantly accelerated global warming within the past few *** to the latest data,it is predicted that the concentration of CO_(2)will rise to 800 ppm over this century,and could reach 2000 ppm by *** high level of CO_(2)is expected to result in significant increase in global temperature as well as ocean acidification[1].

关键词： exceptional global release

Chemical-assisted MMP reduction on methane-oil systems:Implications for natural gas injection to enhanced oil recovery

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Petroleum 2024年第1期10卷 101-108页

作者： mohamed Almobarak Matthew B.Myers Colin D.Wood Yongbing Liu ali Saeedi Quan Xie Discipline of Petroleum Engineering WA School of Mines: Minerals Energy and Chemical Engineering Curtin University Commonwealth Scientific and Industrial Research Organization Curtin University Oil and Gas Innovation Centre Management State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation

Miscible natural gas injection is widely considered as a practical and efficient enhanced oil recovery technique. However, the main challenge in this process is the high minimum miscibility pressure（MMP）between natural gas and crude oil, which limits its application and recovery factor, especially in hightemperature reservoirs. Therefore, we present a novel investigation to quantify the effect of chemicalassisted MMP reduction on the oil recovery factor. Firstly, we measured the interfacial tension（IFT） of the methane-oil system in the presence of chemical or CO2to calculate the MMP reduction at a constant temperature（373K） using the vanishing interfacial tension（VIT） method. Afterwards, we performed three coreflooding experiments to quantify the effect of MMP reduction on the oil recovery factor under different injection *** interfacial tension measurements show that adding a small fraction（1.5 wt%） of the tested surfactant（SOLOTERRA ME-6） achieved 9% of MMP reduction, while adding 20 wt% of CO2to the methane yields 13% of MMP reduction. Then, the coreflooding results highlight the significance of achieving miscibility during gas injection, as the ultimate recovery factor increased from 65.5% under immiscible conditions to 77.2% using chemical-assisted methane, and to 79% using gas mixture after achieving near miscible condition. The results demonstrate the promising potential of the MMP reduction to significantly increase the oil recovery factor during gas injection. Furthermore, these results will likely expand the application envelop of the miscible gas injection, in addition to the environmental benefits of utilizing the produced gas by re-injection/recycling instead of flaring which contributes to reducing the greenhouse gas emissions.

关键词： Gas injection Enhanced oil recovery Miscibility Coreflooding

Investigating and predicting the role of photovoltaic, wind, and hydrogen energies in sustainable global energy evolution

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Global Energy Interconnection 2024年第4期7卷 429-445页

作者： Mahmood Swadi Dheyaa Jasim Kadhim mohamed Salem Firas Mohammed Tuaimah Ammar Sabri Majeed ali Jawad Alrubaie Department of Electrical Engineering College of EngineeringUniversity of BaghdadBaghdad 10001Iraq Libyan Authority for Scientific Research Tripoli 80045Libya School of Electrical and Electronic Engineering Universiti Sains Malaysia(USM)Nibong Tebal 14300PenangMalaysia Continuing Education Center University of BaghdadBaghdad 10001Iraq Al-Furat Al-Awsat Technical University AL-Mussaib Technical CollegeBabylonIraq

The global shift toward next-generation energy systems is propelled by the urgent need to combat climate change and the dwindling supply of fossil *** review explores the intricate challenges and opportunities for transitioning to sustainable renewable energy sources such as solar,wind,and *** transition economically challenges traditional energy sectors while fostering new industries,promoting job growth,and sustainable economic *** transition to renewable energy demands social equity,ensuring universal access to affordable energy,and considering community *** environmental benefits include a significant reduction in greenhouse gas emissions and a lesser ecological *** study highlights the rapid growth of the global wind power market,which is projected to increase from$112.23 billion in 2022 to$278.43 billion by 2030,with a compound annual growth rate of 13.67%.In addition,the demand for hydrogen is expected to increase,significantly impacting the market with potential cost reductions and making it a critical renewable energy source owing to its affordability and zero *** 2028,renewables are predicted to account for 42%of global electricity generation,with significant contributions from wind and solar photovoltaic(PV)technology,particularly in China,the European Union,the United States,and *** developments signify a global commitment to diversifying energy sources,reducing emissions,and moving toward cleaner and more sustainable energy *** review offers stakeholders the insights required to smoothly transition to sustainable energy,setting the stage for a resilient future.

关键词： Next energy Renewable energy Sustainability Environmental benefits Economic opportunities

Estimation of monthly global solar radiation over twelve major cities of Libya

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Energy and Built Environment 2024年第1期5卷 46-57页

作者： Alhassan ali Teyabeen Najeya B.Elhatmi Akram A.Essnid F.mohamed Libyan Center for Solar Energy Research and Studies TripoliLibya Libyan Authority of Scientific Research TripoliLibya

This study aims to estimate monthly averaged daily horizontal global solar *** climatological data collected at twelve major cities located across Libya’s map were used to establish 7 different empirical *** empirical coefficients of the models were calculated using the least square *** accuracy of the models was evaluated using different statistical criteria such as Taylor diagram,mean absolute percentage error,MAPE,and root mean square error,*** results indicated that the sunshine duration-based models are more accurate than air temperature-based models,and the best performance was obtained by the quadratic regression model for all twelve Libyan ***,this regression model can be used for the prediction of monthly mean horizontal global solar radiation at a specific site across Libya’s regions with minimum ***,the results of the global solar irradiance produced by this method can be used for designing solar systems applications.

关键词： Monthly global solar radiation Clearness index Empirical models Performance evaluation Taylor diagram Libya