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Evaluation of rainwater harvesting and shrub establishment methods for sustainable watershed management in northern Afghanistan

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Journal of Mountain Science 2022年第8期19卷 2346-2359页

作者： LOUHAICHI Mounir HASSAN Sawsan GAMOUN Mouldi SAFI Navin abdallah mohamed a.b. ATES Serkan International Center for Agricultural Research in the Dry Areas(ICARDA) Tunis 1004Tunisia Department of Animal and Rangeland Sciences Oregon State UniversityCorvallisOR 97331USA International Center for Agricultural Research in the Dry Areas(ICARDA) Amman 11185Jordan Consultant-Field Assistant Mazar Sharif 1703Afghanistan

Watershed rangelands in Northern Afghanistan provide various ecosystem services that support the local people's livelihoods,but they are now highly degraded essentially due to the continuous high grazing pressure and recurrent *** of shrub establishment method enhanced by water harvesting techniques to rehabilitate degraded rangelands have not been well *** main goal of this study was to evaluate the impact of direct seeding and transplanting of seedlings in combination with semi-circular bunds on growth,yield,and survival rate of four shrub species(Atriplex halimus,Atriplex nummularia,Atriplex lentiformis,andMaireana.b.evifolia)under semi-arid conditions of Sayyad village,Khulm *** rate(%),plant height,width,and plant length(cm)and plant cover(%)were measured for each plant over five occasions.A non-destructive reference unit was used to estimate biomass *** results showed that growth attributes and biomass production of shrubs were consistently greater in the transplanting compared to direct *** average,the plant length,width,height,volume,cover,and biomass production of transplanted shrubs were greater than direct-seeded shrubs by 24.3%,8.6%,8.7%,121.5%,13.8% and 34.1%,*** production of transplanted seedlings was the highest for ***(1313.5 g DM/plant)and ***(800 g DM/plant).There was a strong correlation between plant biomass production and plant volume(R^(2)_(Plant volume)=0.88)for the shrub ***,indicating that plant volume is a key variable for assessing biomass production for this ***,the survival rate of *** was 100% in both planting methods,suggesting that based on better survival this halophytic plant has great potential when restoring degraded ***,on the basis of better growth rates,yield,and survival,transplanting *** *** may enhance shrub establishment and contribute to the rehabilitation of slop

关键词： biomass production Land degradation Rangeland rehabilitation Seed germination Shrub survival Vegetation cover Water harvesting

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Seismic performance of high-rise buildings in selected regions in Saudi Arabia according to different seismic codes

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Earthquake Engineering and Engineering Vibration 2021年第1期20卷 179-191页

作者： Sayed Mahmoud mohamed Alsearheed Waleed abdallah Department of Civil and Construction Engineering College of EngineeringImam Abdulrahman Bin Faisal UniversitySaudi Arabia Department of building Engineering College of ArchitectureImam Abdulrahman Bin Faisal UniversitySaudi Arabia Department of Civil Engineering College of Engineering at MatariaHelwan UniversityCairoEgypt

The design code for each country is revised and updated based on an expected zone’s seismic intensities,geotechnical site classifications,structural systems,construction materials and methods of construction in order to provide more realistic considerations of seismic demand,seismic response,and seismic *** on the aforementioned provisions,structures designed according to different seismic codes may yield different performances for the same level of *** study aims to investigate and compare the induced responses related to the earthquake-resistant design of reinforced concrete(RC)buildings according to the Saudi building code(SbC-301),American code(ASCE-7),uniform building code(UbC-97),and European code(EC-8).In order to account for the provision regarding the hazard specification and its effect on the induced seismic responses,four regions in the Kingdom of Saudi Arabia with different seismic levels are *** code provisions related to the specification of site classification and its effect on the induced design base shear are investigated as *** differences are observed in the induced responses with the variation in seismic design codes for the considered seismic hazards and site classifications.

关键词： high-rise building SbC-301 international seismic codes seismic zones site classifications

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Geochemical Stream Sediment Survey in the Wadi Umm Rilan Area,South Eastern Desert,Egypt:A New Occurrence for Gold Mineralization

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Acta Geologica Sinica(English Edition) 2017年第3期91卷 1041-1062页

作者： mohamed abdallah Gad DARWISH Geology Department Faculty of ScienceAswan University

The present paper investigates the stream sediment geochemistry, behavior of gold and associated elements, delineates Au-anomalous sites and defines related sources in the Wadi Umm Rilan area. Fifty three major and trace elements were analyzed using ICP-MS and treated applying various statistical and mapping techniques. The results showed a significant difference of mean and median Au and most chemical elements in the three portions of the area, and higher values were recorded in the western portion. Furthermore, Au-anomalous sites appeared in upper and lower parts of the Wadi Umm Rilan, along the tributaries of metavolcanic unit and near granitoid contacts. This indicates the main source of Au mineralization is related to emplacement of granitoid plutons and accompanying hydrothermal solutions. There are significant indications for the presence of more than one mineralization event forming a probable single major episode of mineralization in the area, involving Au, Pb and U mineralizations. Geology, geomorphologic aspects and weathering processes could control stream sediment geochemistry, anomalies of Au and associated elements, elemental association and their dispersion patterns. Therefore, the area is fruitful and regarded as a promising target for Au exploration, using Ag, As, Sb, Cd, Cs, and TI as pathfinder elements.

关键词： geochemical survey stream sediments Au mineralization Wadi Umm Rilan area southEastern Desert Egypt

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Microchemical Characterization of Natural Gold and Copper Alloys from the Ancient Um Shashoba Gold Mine, South Egypt

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Acta Geologica Sinica(English Edition) 2014年第1期88卷 196-212页

作者： mohamed abdallah Gad DARWISH Geology Department Faculty of Science Aswan University

The SEM-EDX technique was applied to investigate Au, and Cu＋Sn alloyed grains in the mineralization of the Um Shashoba mine for achieving further understanding of occurrences, internal structures and microchemistry of Au and Cu alloys and associated minerals, and mineralization type. This study is aiming at the genetic history of ore-bearing fluid events, geochemical evaluation and exploration significance. The results showed that the mineralization could be considered as a single major episode generated by metamorphic mesothermal solution rich in sulfides and unsaturated respect to Au. It was differentiated into many stages; started with formation of auriferous pyrite that was pseudomorphed by secondary hematite, limonite and goethite. Three phases of Au alloy were precipitated, and Cu＋Sn and Ag-rich alloys were produced respectively and followed by deposition of two generations of barren pyrite. Calcite and ankerite were crystalized, surrounded and partially replaced some of early formed minerals. Finally, barren muscovite recrystallized around and inside both later formed ca.b.nate minerals that were free of any sign of Au in their structures. The processes of deformation, recrystallization, annealing, dissolution, remobilization and re-precipitation played the most important roles in the genetic history of the mineralization.

关键词： SEM–EDX analyses Au and Cu alloy grains Um Shashoba gold mine Egypt

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Geochemical and Environmental Evaluation of Um Shashoba Gold Mine Area,Southeastern Desert,Egypt

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Acta Geologica Sinica(English Edition) 2011年第4期85卷 881-898页

作者： mohamed abdallah Gad DARWISH Geology Department Aswan Faculty of ScienceSouth Valley UniversityPost No.81528 AswanEgypt

A suite of elements（Ag,Au,ba.b.,Cd,Co,Cr,Cu,Ga,Hf,Hg,Mn,Mo,Ni,Pb,Rb,Sb,Se, Sr,Te and Zn）,total organic ca.b.n（TOC）and pH were analyzed in stream sediment and tailing samples from Um Shashoba area,in order to evaluate Au placer and the sediments being impacted by old mining *** results were examined using statistical,graphical and mapping *** spite of the results revealing that Au and most of the elements in sediments were in general significantly lower than those in tailing,Au was concentrated in the NE and SW parts forming Au *** is remarkably a close association of Au with Hg and Sb;both are useful as pathfinder elements for Au *** of pH could not control a fate of analyzed elements,whereas TOC and Mn oxides and hydroxides could uptake some elements Au,ba,Co,Cr,Hg,Ni,and *** results also indicated that the sediments were contaminated by anthropogenic factors causing moderate,strong to very strong pollution with respect to bi,Se and Te,***,geogenic factors could also contribute elemental enrichment to the drainage system and cause significant toxicity level.

关键词： geochemical exploration environmental evaluation Um Shashoba gold mine Egypt

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Geochemistry of the High Dam Lake sediments,south Egypt:implications for environmental significance

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International Journal of Sediment Research 2013年第4期28卷 544-559页

作者： mohamed abdallah Gad DARWISH Geology department Faculty of ScienceAswan University

The goal of the present work is to perform a geochemical assessment of High Dam Lake bottom sediments for determining the fate,dispersion and levels of trace elements causing environmental pollution,and provided an access to their probable *** sediment samples were analyzed using ICP-MS for 20 elements;Ag,ba,Cr,Cu,Ga,Hf,Mn,Pb,Rb,Sc,Sc,Sn,Sr,Ta Th Ti,T1,U,V and Zr,and their obtained data were treated using statistical,graphical and mapping *** results showed the data set of all analyzed elements affected by outliers and extreme values that caused deviation away from *** Wallis test revealed that median of some trace clement levels in Lake sediments,was not significantly different and other elements rejected the Null *** analyzed elements had high values of median and mean in sediments of Lake Nubia rather than Lake Nasser and their normalization gave the same results of calculated environment ***,Lake Nubia sediments possessed high combined EF levels of Th,Sc,Sn,Ag,Zr,Hf,Ta,Sr,U,Ti,V,Cr,and Mn,causing significant contamination,which was great potentially related to industrial,agricultural,urbanization and mining ***,combined EF of Se,Cu,Ga,Pb,ba,Rb,and Tl,which are highly elevated in southern Lake Nasser sediments owing to their source are great possibly derived from Lake Nubia and geogenic *** decreasing distance towards the High Dam body,the contaminant elements were diminished due to reduction in the environmental factors and Sudanese pollution sources leading to the northern Lake Nasser considered to be less ***,the present study is an environmental alert for contaminated sediments that carried contaminants and considered the secondary source of pollution impact on ecosystem,and subsequently,their environmental risk on Human health.

关键词： Geochemistry High Dam Lake sediments Environmental significance South Egypt

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Ecological risk assessment of surficial sediment by heavy metals from a submerged archaeology ha.b.r,South Mediterranean Sea,Egypt

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Acta Geochimica 2020年第2期39卷 226-235页

作者： Maha Ahmed mohamed abdallah Ahmed mohamed badr-ElDin Marine Pollution Lab National Institute of Oceanography and FisheriesAlexandriaEgypt Oceanography Department Faculty of ScienceAlexandria UniversityAlexandriaEgypt

A protected semi-enclosed embayment,the Eastern Ha.b.r(EH),is situated in the central sector of the Mediterranean coast of Alexandria,*** is a famous fishing dock and water-sport center and its importance arose after the discovery of the Ptolemaic royal quarter of ancient *** protect this national treasure and improve its environmental health,the untreated anthropogenic effluents,which continued for decades into the EH since 1992,must be totally ***,it is an important issue to continually monitor and asses the environmental status of the *** sediment texture,total organic ca.b.n,and the accumulation,distribution,and ecological risks of Cd,Cr,Pb,As,Hg and A1 were determined with a total of 14 surficial sediments samples collected in the EH during *** contents were compared to the literature data to assess the pollution status of *** factors,Degree of contamination(mCd)and potential ecological risk were calculated as a criterion of possible *** mCd calculation produces an overall average value for a range of pollutants,in the present study the contamination factor that provides a measure of the degree of overall contamination in the surface layers in a particular sampling site may provide a.b.tter indication of the state of pollution in the EH sediments than other indicators.

关键词： Heavy metals Eastern ha.b.r Enrichment factors Degree of contamination Potential ecological risk

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DECAY ESTIMATES FOR ISENTROPIC COMPRESSIbLE MAGNETOHYDRODYNAMIC EQUATIONS IN bOUNDED DOMAIN

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Acta Mathematica Scientia 2012年第6期32卷 2211-2220页

作者： mohamed Ahmed abdallah 江飞谭忠 School of Mathematical Sciences Xiamen University College of Mathematics and Computer Science Fuzhou University Institute of Applied Physics and Computational Mathematics

In this paper, under the hypothesis that y is upper bounded, we construct a Lyapunov functional for the multidimensional isentropic compressible magnetohydrodynamic equations and show that the weak solutions decay exponentially to the equilibrium state in L2 norm. Our result verifies that the method of Daoyuan Fang, Ruizhao Zi and Ting Zhang I1] can be adapted to magnetohydrodynamic equations.

关键词： Navier-Stokes equations weak solution decay estimates magnetohydrody-namic

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Mitochondrial dysfunction and alcohol-associated liver disease:a novel pathway and therapeutic target

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Signal Transduction and Targeted Therapy 2020年第1期5卷 2292-2293页

作者： mohamed A.abdallah Ashwani K.Singal Department of Medicine University of South DakotaSanford School of MedicineSioux fallsSDUSA Division of Gastroenterology and Hepatology University of South DakotaSanford School of MedicineSioux fallsSDUSA Avera University Hospital Transplant Institute&Chief Clinical Research Affairs Transplant HepatologyInstitute of Human Genetics ResearchSioux FallsSD 57105USA

In a recent study in signal transduction and targeted therapy,Zhou et *** novel experimental data on the role of DNAdependent protein kinase catalytic subunit(DNA-PKcs)in causing abnormalities in the structure and fun... 详细信息

关键词： al liver alcohol

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Geochemistry of an Alaskan-type mafic-ultramafic complex in Eastern Desert, Egypt:New insights and constraints on the Neoproterozoic island arc magmatism

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Geoscience Frontiers 2019年第3期10卷 941-955页

作者： Shehta E.abdallah Shehata Ali mohamed A.Obeid Geology Department Faculty of Science Zagazig University Geology Department Faculty of Science Minia University Geology Department Faculty of Science Fayoum University Faculty of Petroleum and Mining Sciences Alexandria University (Matrouh Branch)

Mikbi intrusion(MI) is a part of the Neoproterozoic Nubian Shield located along the NE-SW trending major fracture zones prevailing southern Eastern Desert of Egypt. In this study, we present for the first time detailed mineralogical and bulk-rock geochemical data to infer some constraints on the parental magma genesis and to understand the tectonic processes contributed to MI formation. Lithologically, it is composed of fresh peridotite, clinopyroxenite, hornblendite, anorthosite, ga.b.onorite, pyroxene amphibole ga.b.o, amphibole ga.b.o and diorite. All rocks have low Th/La ratios(mostly b, Ta, Zr and Hf together with sub-chondritic ratios of Nb/Ta(2-15) and Zr/Hf(19-35),suggesting that their mantle source was depleted by earlier melting extraction event. The oxygen fugacity(logfO_2) estimated from diorite biotite is around the nickel-nickel oxide buffer(NNO) indicating crystallization from a relatively oxidized magma. Amphiboles in the studied mafic-ultramafic rocks indicate relative oxygen fugacity(i.e. ΔNNO; nickel-nickel oxide) of 0.28-3 and were in equilibrium mostly with 3.77-8.24 wt.% H_2 O_(melt)(i.e. water content in the melt), consistent with the typical values of subduction-related magmas. Moreover, pressure estimates(0.53-6.79 kbar) indicate polybaric crystallization and suggest that the magma cha.b.r(s) was located at relatively shallow crustal levels. The enrichment in LILE(e.g., Cs, ba, K and Sr) and the depletion in HFSE(e.g., Th and Nb) relative to primitive mantle are consistent with island arc signature. The olivine, pyroxene and amphibole compositions also reflect arc affinity. These inferences suggest that their primary magma was derived from partial melting of a mantle source that formerly metasomatized in a subduction zone setting. Clinopyroxene and bulkrock data are consistent with orogenic tholeiitic affinity. Conse

关键词： Alaskan-type complex Neoproterozoic Arc magmatism Eastern desert Egypt

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