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A Novel Approach in Hydrogeochemical exploration for Uranium Mineralization:an example from West Central Sinai,egypt

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Acta Geologica Sinica(english edition) 2015年第6期89卷 1895-1913页

作者： Ahmed e.el-RAYeS Mohamed O.ARNOUS Suez Canal University Faculty of SciencesGeology Department

Groundwater in contact with ore deposits may acquire a chemical composition that could be used as a guide for exploration. eight well-water samples are collected from a known uraniummineralized area near Abu Zenima, west central Sinai to examine the applicability of using the hydrogeochemical technique in the search for uranium mineralization in similar arid areas. The analytical chemical data of the ground water is compared with ground radiometric measurements. The obtained results indicate that groundwater affected by uranium mineralization has a specific relativity of major anions expressed essentially as SO_4〉Cl〉HCO_3 and to a lesser extent as Cl〉SO_4〉HCO_3, associated as a rule with low magnesium content. This association constitutes a signature of uranium mineralization on the composition of groundwater in west central Sinai and could be used as an important exploration guide in the search for uranium deposits in similar areas. Anomalies in Ni, Fe, Zn and Cr and other pathfinder elements in groundwater can furnish geochemical guides to uranium ores. The immobile trace.element anomalies, including Zn, Ni and Fe are strongly distributed near the orebody; whereas the relatively mobile trace.elements, including Co, U, V and Cr, constitute the dispersion haloes away from the orebody. A new hydrogeochemical discrimination diagram is constructed to be used as a quick and cost effective exploration tool in the search for uranium occurrences in environmentally similar arid areas. Based on the obtained results, a new site for uranium occurrence, west of W. Baba, is delineated and recommended for future detailed geological and geochemical surveying.

关键词： Hydrogeochemical exploration Uranium ores geospatial mapping graphical explorationtool remote sensing Sinai

Hydrothermal Characteristics of Blended Cement Pastes Containing Silica Sand Using Cement Kiln Dust as an Activator

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Journal of Materials Science & Technology 2002年第5期18卷 474-478页

作者： S.A.Abo-el-enein F.I.el-Hosiny e.el-Shimy T.A.Osman Faculty of Sci. Ain Shams Univ. Abbassia-Cairo Egypt Building Res. Cent. Cairo P. O. Box 1770 Egypt

The hydrothermal reactivity of silica sand was studied using cement kiln dust (CKD) as an activator in addition to the Portland cement fraction of el-Karnak cement (a blend of ordinary Portland cement and ground sand). Autoclaved eI-Karnak cement pastes were studied at pressures of 0.507, 1.013 and 1.520 MPa of saturated steam with respect to their compressive strength, kinetics of hydrothermal reaction and the phase composition of the formed hydrates. The role of CKD in affecting the physicochemical and mechanical properties of eI-Karnak cement pastes was studied by autoclaving of several pastes containing 5, 7.5, 10 and 20% CKD at a pressure of 1.013 MPa of saturated steam. CKD was added either as a raw CKD (unwashed) or after washing with water (washed CKD). The results of these physicochemical studies obtained could be related as much as possible to the role of CKD (raw or washed) in affecting the hydrothermal reactivity of silica sand in eI-Karnak cement pastes.

关键词： Blended cement Silica Cement kiln dust Hydrothermal characteristics

extraordinary piezoelectric effect induced in two-dimensional rare earth monochalcogenides via reducing system dimensionality

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Journal of Materiomics 2023年第1期9卷 72-81页

作者： Neveen I.Atallah Maged el-Kemary Fabien Pascale Khaled e.el-Kelany Institute of Nanoscience and Nanotechnology Kafrelsheikh University33516Kafr el-skiekhEgypt Universite de Lorraine-Nancy CNRSLaboratoire de Physique et Chimie TheoriquesUMR 7019Vandoeuvre-les-NancyFrance

Piezoelectricity is pivotal for applications in micro/nanoelectromechanical systems(MeMS/NeMS).Inducing such a property in 2D systems via the reduction of the dimensionality of their corresponding 3D bulk is here *** on DFT theory and Gaussian-type-localized basis sets,the structural,electronic,mechanical,and piezoelectric properties of both 3D and 2D rare earth monochalcogenides RmX(Rm=Tm,Yb,Lu,and X=S,Se,Te)are investigated using the CRYSTAL *** intriguingly,the 2D LuX compounds display a buckled structure,where the Lu and X atoms protrude from the monolayer surface leading to an additional out-of-plane piezoelectric effect;(e_(31)=2104.84,1770.28,1689.79 pC/m,and d31=56.37,49.76,and 147.90 pm/V for LuS,LuSe,and LuTe,respectively).Such piezoelectric response is two orders of magnitude larger than the one of recently reported 2D ferroelectric MXenes,and is nearly thirty times larger than the commonly used AlN and GaN bulk ***,the reduced elastic constants obtained,when compared to other 2D materials,confirm the flexibility and softness of the considered 2D systems.

关键词： 2D materials Rare earth monochalcogenides DFT Gaussian basis CRYSTAL code Piezoelectric effect MeMS/NeMS

Problems of drinking water treatment along Ismailia Canal Province, egypt

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第3期9卷 232-242页

作者： Mohamed H.GeRIeSH Klaus-Dieter BALKe Ahmed e.el-RAYeS Geology Department Faculty of ScienceSuez Canal UniversityP.C.41522IsmailiaEgypt Institute of Geosciences Teubingen University72076 TeubingenGermany

The present drinking water purification system in egypt uses surface water as a raw water supply without a preliminary filtration *** the other hand,chlorine gas is added as a disinfectant agent in two steps,pre-and *** to these reasons most of water treatment plants suffer low filtering effectiveness and produce the trihalomethane(THM) species as a chlorination *** Ismailia Canal represents the most distal downstream of the main Nile *** its water contains all the proceeded pollutants discharged into the *** addition,the downstream reaches of the canal act as an agricultural drain during the closing period of the High Dam gates in January and February every ***,the wide industrial zone along the upstream course of the canal enriches the canal water with high concentrations of heavy *** obtained results indicate that the canal gains up to 24.06×106 m3 of water from the surrounding shallow aquifer during the closing period of the High Dam gates,while during the rest of the year,the canal acts as an influent stream losing about 99.6×106 m3 of its water *** reduction of total organic carbon(TOC) and suspended particulate matters(SPMs) should be one of the central goals of any treatment plan to avoid the disinfectants *** combination of sedimentation basins,gravel pre-filtration and slow sand filtration,and underground passage with microbiological oxidation-reduction and adsorption criteria showed good removal of parasites and bacteria and complete.elimination of TOC,SPM and heavy ***,it reduces the use of disinfectants chemicals and lowers the treatment ***,this purification system under the arid climate prevailing in egypt should be tested and modified prior to application.

关键词： Drinking water treatment Hazardous by-products Natural attenuation Ismailia Canal egypt

GIS-based flash flooding susceptibility analysis and water management in arid mountain ranges:Safaga Region,Red Sea Mountains,egypt

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Journal of Mountain Science 2023年第12期20卷 3665-3686页

作者： Ahmed e.el-RAYeS Mohamed O.ARNOUS Ahmed M.HelMY Geology Department Faculty of ScienceSuez Canal UniversityIsmailia 41522Egypt Geology Department Faculty of ScienceArish UniversityArish 45511 North SinaiEgypt

The Safaga Region(SR)is part of the Red Sea mountain range in *** flash flooding is now an inescapable event,wreaking havoc and causing massive loss of life and *** majority of the floodwater,however,has been wasted as runoff to the Red Sea,which,if used wisely,could meet a fraction of the water demands for a variety of applications in this *** current work aims to use GIS techniques to integrate remote sensing data for evaluating,mitigating,and managing flash floods in *** data set comprised Tropical Rainfall Measuring Mission(TRMM)thematic rainfall data,1:50,000 scale topographical map sheets,geological maps,the ASTeR Digital elevation Model(ASTeR GDeM),Landsat 7 enhanced Thematic Mapper"(eTM7+),and Landsat 8 Operational Land *** flash flood risk model of SR is de.eloped using ArcGIS-10.3 geoprocessing tools integrating all the causal factors thematic *** final flood risk model for the SR suggests that 57%of the total basins in the SR are at high risk of *** 38%of all basins are at moderate flood *** remaining 5%of basins are less prone to ***-prone zones were identified,suitable dam-building sites were located,and extre.ely probable areas for water recharge were *** the basis of reliable scientific data,structural and non-structural mitigation strategies that might reduce the damage susceptibility,alleviate the sensitivity of the flash flood,and best utilize its water supply were recommended.

关键词： Flash floods GIS Susceptibility Water management Arid mountains egypt

Structural and electronic characteristics of pure and doped ZnO varistors

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Chinese Physics B 2012年第11期21卷 352-360页

作者： A.Sedky e.el-Suheel Physics Department Faculty of ScienceKing Faisal University Physics Department Faculty of ScienceAssiut University

We report here the structural, surface morphology, mechanical, and current voltage characteristics of Zn1-xMxO ceramic samples with various x and M （0.00≤〈 x ≤ 0.20, M = Ni, Cu）. It is found that the considered dopants do not influence the well-known peaks related to the wurtzite structure of ZnO ceramics, while the shapes and the sizes of grains are clearly affected. The average crystalline diameters deduced from the SeM micrographs are between 2.06 μm and 4.8 μm for all samples. The oxygen element ratio is increased by both dopants. Interestingly, the potential barrier can be formed by adding Cu up to 0.20, while it is comple.ely deformed by 0.025 Ni addition. The breakdown field can be enhanced up to 4138 V/cm by 0.025 Cu addition, followed by a decrease with further increase of Cu up to 0.20. On the other hand, a gradual decrease in Vickers microhardness is reported for both dopants, and the values in the Ni samples are higher compared to those in the Cu samples. The.electricul conductivity is generally improved by Ni, while the addition of Cu improves it only in the over doped region （≥ 0.10）. These results are discussed in terms of the differences of valency and ferromagnetic ordering.

关键词： semiconductors chemical synthesis impurity electronic transport

An Improved DeepNN with Feature Ranking for Covid-19 Detection

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Computers, Materials & Continua 2022年第5期71卷 2249-2269页

作者： Noha e.el-Attar Sahar F.Sabbeh Heba Fasihuddin Wael A.Awad Faculty of Computers and Artificial Intelligence Benha UniversityBenha13518Egypt University of Jeddah College of Computer Science and EngineeringJeddah21493Kingdom of Saudi Arabia Faculty of Computers and Information Damietta UniversityDamietta34711Egypt

The outbreak of Covid-19 has taken the lives of many patients so *** symptoms of COVID-19 include muscle pains,loss of taste and smell,coughs,fever,and sore throat,which can lead to severe cases of breathing difficulties,organ failure,and ***,the early detection of the virus is very ***-19 can be detected using clinical tests,making us need to know the most important symptoms/features that can enhance the decision *** this work,we propose a modified multilayer perceptron(MLP)with feature selection(MLPFS)to predict the positive COVID-19 cases based on symptoms and features from patients’electronic medical records(eMR).MLPFS model includes a layer that identifies the most informative symptoms to minimize the number of symptoms base on their relative *** the model with only the highest informative symptoms can fasten the learning process and increase *** were conducted using three different COVID-19 datasets and eight different models,including the proposed *** show that MLPFS achieves the best feature reduction across all datasets compared to all other experimented ***,it outperforms the other models in classification results as well as time.

关键词： Covid-19 feature selection deep learning