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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

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 carbonate 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

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

The effect of hydrogel particle size on water retention properties and availability under water stress

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international Soil and Water Conservation Research 2019年第3期7卷 275-285页

作者： Ahmad M.abdallah Department of Natural Resources and Agricultural Engineering Faculty of AgricultureDamanhour University59 DamanhourEgypt

The use of superabsorbent polymers or hydrogels could increase the water holding capacity (WHC) of sandy soil and reduce water loss by deep ***,hydrogels' retained water availability to plants might be overestimated without taking into consideration the hydrogel particles ***,the ultimate objective of this study was to address the impacts of hydrogel particles size on hydrogel's retained water availability (plant available water,PAW),daily water consumption (DWC) and survival of Guava seedlings subjected to ***,some soil physical properties,i.e.,WHC,water retention properties,and hydraulic conductivity (Ksat) were *** (WaterSorb,'WS') application,particularly the WS of small particles,significantly reduced Ksat,and increased WHC and ***,seedlings grown in soil amended with WS fine (0.8-1.0 mm),WS medium (1.0-2.0 mm) and WS large (2-4 mm) survived for 27.0 ± 1.3,24.0 ± 1.1 and 17.0 ± 0.7 days,respectively,compared to 13.0 ± 1.0 days for the *** water stored in the WS of large particles was less readily available for plant ***,hydrogels,had no effect on the DWC of the *** hydrogels as a soil amendment increases WHC PAW,growth and survival of Guava seedlings,while the effect was less pronounced for the large hydrogel particles which had lower specific surface area and swelling rate.

关键词： Water holding capacity Swelling rate Water consumption Available water capacity Seedlings survival

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,Bi,Cd,Co,Cr,Cu,Ga,Hf,Hg,Mn,Mo,Ni,Pb,Rb,Sb,Se, Sr,Te and Zn）,total organic carbon（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

Edge Computing Platform with Efficient Migration Scheme for 5G/6G Networks

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Computer Systems Science & Engineering 2023年第5期45卷 1775-1787页

作者： Abdelhamied A.Ateya Amel Ali Alhussan Hanaa A.abdallah Mona A.Al duailij Abdukodir Khakimov Ammar Muthanna Department of Electronics and Communications Engineering Zagazig UniversityZagazigSharqia44519Egypt Department of Computer Sciences College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of information Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh84428Saudi Arabia Department of Applied Probability and informatics Peoples’Friendship University of Russia(RUDN University)Moscow117198Russia Center for Telecommunication Research School of Postgraduate Studies&ResearchSri Lanka Technological CampusPadukka10500Sri Lanka

Next-generation cellular networks are expected to provide users with innovative gigabits and terabits per second speeds and achieve ultra-high reliability,availability,and ultra-low *** requirements of such networks are the main challenges that can be handled using a range of recent technologies,including multi-access edge computing(MEC),artificial intelligence(Ai),millimeterwave communications(mmWave),and software-defined *** aspects and design challenges associated with the MEC-based 5G/6G networks should be solved to ensure the required quality of service(QoS).This article considers developing a complex MEC structure for fifth and sixth-generation(5G/6G)cellular ***,we propose a seamless migration technique for complex edge computing *** developed migration scheme enables services to adapt to the required load on the radio *** proposed algorithm is analyzed for various use cases,and a test bench has been developed to emulate the operator’s *** obtained results are introduced and discussed.

关键词： 5G 6G mobile edge computing migration offloading quality of service

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油基钻井液体系轻烃组分分配系数计算及应用

石油勘探与开发 2022年第4期49卷 787-797页

作者： abdallah Bacem Rabie Ben AHMADi Riadh LYNEN Frederic REKHiSS Farhat 突尼斯斯法克斯国家工程学院LR3E实验室斯法克斯3000突尼斯比利时根特大学有机与高分子化学系根特9000比利时

采用一种基于静态顶空气相色谱技术的热力学方法研究了油基钻井液、地层流体和钻井液气体之间的关系,计算了两种油基钻井液-空气体系nC_(5)—nC_(8)范围内47种轻烃组分的分配系数,在热力学平衡条件下开展原始地层流体组分重构。研究表明... 详细信息

采用一种基于静态顶空气相色谱技术的热力学方法研究了油基钻井液、地层流体和钻井液气体之间的关系,计算了两种油基钻井液-空气体系nC_(5)—nC_(8)范围内47种轻烃组分的分配系数,在热力学平衡条件下开展原始地层流体组分重构。研究表明,油基钻井液对钻井液气体中nC_(5)—nC_(8)范围内的地层流体组分的影响很小,对于低毒性合成油基钻井液,影响小于1%,对于柴油基钻井液,影响小于10%。对于多数轻烃组分,采用气相校准法和直接定量法确定的分配系数的误差小于10%,直接定量法计算的分配系数更准确。两种原油样品重构组分与真实组分之间的匹配度分别为91%和89%,证明利用nC_(5)—nC_(8)范围内轻烃组分分配系数通过静态顶空分析重构原始地层流体组分的可行性和准确性较高。

关键词：油基钻井液钻井液气体轻烃组分分配系数地层流体

Apatite phosphate doped by cobalt as hight efficient catalyst of multi-component synthesis of therapeutic spiropyrimidine compound

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Natural Products and Bioprospecting 2022年第1期12卷 567-572页

作者： abdallah Rhihil Youness Aichi Mohamed Zahouily Saïd Sebti Mohamed El Guendouzi Laboratory of Chemistry Physics Materials and Catalysis(LCPMC) Faculty of Sciences Ben M’sik of CasablancaHassan II University of CasablancaCasablancaMorocco Financial Engineering Governance and Development LaboratoryNational School of Business and Management of CasablancaHassan II University of CasablancaCasablancaMorocco Laboratory of Materials Catalysis and Valorization of Natural ResourcesFaculty of Sciences and Technology of MohammediaHassan II University of CasablancaCasablancaMorocco

Spiropyrimidines vanquish a significant situation in the field of heterocyclic chemistry, they are broadly utilized as an antibacterial, an inhibitor of multidrug opposition, or an antiplatelet and antithrombotic drug. Phosphate, the principal Moroccan mineral wealth occupies a vital spot in the economic sector and its valuation is a goal continually looked for. Among the conceivable outcomes of valorization, its utilization in heterogeneous catalysis which thought about an exceptionally encouraging new way. in this context, the focus on the reaction of the synthesis of spiropy-rimidine, catalyzed by natural phosphate (NP) and by fluoroapatite (Fap), are used alone or doped by cobalt. These phosphate catalysts were characterized by XRD, iR and SEM, while the synthesized spiropyrimidine was identified by iR, GC-MS and NMR. The obtained yield with fluorapatite doped by cobalt (Co/Fap), at room temperature in ethanol is very high and shows a high impact performance induced by a synergistic effect compared to that of NP alone.

关键词： Spiropyrimidine Natural phosphate Co/Fap Heterogeneous catalysis Multicomponent reaction

Prevalence of iron Deficiency Anemia among Moroccan Pregnant Women

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Open Journal of Obstetrics and Gynecology 2022年第12期12卷 1258-1266页

作者： abdallah El Farouqi Meryem Rabbani abdallah Moukal Mohamed Aghrouch Farida Ajdi Department of Obstetric and Gynecology UHC Agadir Agadir Faculty of Medicine and Pharmacy Agadir Morocco Dietitian-Nutritionist Health Universe Agadir Morocco Medical Analysis Laboratory Regional Hospital Center Agadir Morocco Endocrinology Department UHC Agadir Agadir Faculty of Medicine and Pharmacy Agadir Morocco

Background: iron deficiency anemia in pregnant women is a serious public health problem, especially in developing countries. Aim: The objective of this study is to determine the prevalence of iron deficiency anemia and its associated factors during pregnancy in the south of Morocco. Methods: A cross-sectional study was carried in the regional Hospital Center Hassan ii (RHC) from April to august 2021 in all the pregnant women coming for consultation in the maternity service. 500 pregnant women were randomly recruited for the study. A complete blood count and serum ferritin was performed in every case. They have been the subjects of a questionnaire containing their background and health data. The analysis of our data was done by the iBM SPSS Statistics 25 software. Results: The prevalence of iron deficiency anemia was 20% with a Ci of (44.7% - 53.5%). The most affected age group was 25 to 35 years with a rate of 42.86%. The majority of women had mild anemia (84.61%) followed by moderate anemia (11.54%) and severe anemia (3.85%). 57.14% of the anemic pregnant women were primigravida. The results of serum ferritin made it possible to identify 70% of women deficient, with a dominance of normocytic normochromic anemia. The influence of geographic origin and place of birth was not significant. Conclusion: The prevalence of iron deficiency anemia is more or less low in our study. However, there is a high prevalence of iron deficiency and anemia during pregnancy. Statistically, there was no significant association between iron deficiency anemia and the various parameters studied, such as age, parity, origin and place of birth.

关键词： iron Deficiency Anemia Pregnancy Prevalence