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The possible source of uranium mineralization in felsic volcanic rocks,Eastern Desert,Egypt of the Arabian-Nubian Shield:Constraints from whole-rock geochemistry and spectrometric prospection

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Acta Geochimica 2021年第5期40卷 819-845页

作者： Gehad.m.Saleh bahaa.m.emad Ibrahim.B.Abdel Kader Rania.m.Sakr Nuclear materials Authority El MaadiP.O.Box 530CairoEgypt

The present work deals with the detailed geology,mineralogy,geochemistry,and spectrometric prospection of the felsic volcanic rocks at the Eastern Desert,Egypt of the Arabian-Nubian *** volcanic rocks are an essential source for rare earth elements(REEs)and uranium occurrences in this *** are compositionally uniform with tholeiitic to calc-alkaline affinities,peraluminous and belong to the series of rhyolite with high-K *** exhibit more enrichment in high field strength elements(HFSE,***,Ta,Nd,Th,and U)and large-ion lithophile elements(LILE,*** and Rb)compared to the country rocks of the studied area,with REE ranging from 188.20 to 442.70 ppm and strong depletion in Ti,Sr,P with deep negative Eu *** felsic volcanic rocks were mostly generated from the partial melting of quartz-amphibolite facies accreted during the *** oddities of Zr-U-Th for the felsic volcanic rocks determine the involvement of crustal *** volcanic rocks are found in A-type suites of magma and represent highly fractionated rocks derived from rhyolitic magma,with insignificant interaction with continental crust in the low-pressure environment and during fractional *** volcanic rocks have higher values of radioactivity in which eU range from 0.5 to 121 ppm and eTh from 1.0 to 415.10 *** high values of eU and eTh can be ascribed to the mineralization of uranium and the presence of accessory minerals of radiogenic nature such as uranophane,uranothorite,zircon,and *** is considered as the mineral with most enriched uranium contents in the studied felsic volcanic rocks in which(UO2=87.30 wt%).Also,they are enriched with REE-bearing accessory minerals comprising allanite,titanite,and *** geological investigations of the felsic volcanic rocks in the studied areas are inappropriate to clear the feasible economic potentialities of rare earth elements and U occurrences;itemized and invaluable

关键词： Felsic volcanic rocks Geochemistry REE Uranium mineralization Egypt Arabian-Nubian Shield

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Geochemistry and spectrometric prospection of younger granites and granitic pegmatites bearing uranium mineralization at *** El Rakeb area, Central Eastern Desert, Egypt

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Acta Geochimica 2021年第4期40卷 575-601页

作者： Gehad m.Saleh bahaa.m.emad Ibrahim B.Abdel Kader Nuclear materials Authority El MaadiP.O.Box 530CairoEgypt

The present study deals with the detailed field geology,mineralogy,geochemistry,and spectrometric prospection of rare metals and radioactive minerals associated with granitic pegmatites in the Gabal Um LassafAbu Dob-Um Atelia-Kadabora-Kab El Rakeb area(LDAKK),which are situated in the central Eastern Desert of *** study area is composed of granodiorites and *** latter is dissected by granitic pegmatites with a discriminatory distribution of economically important mineralization(rare-metals and U-Th minerals).The granitic pegmatites display a zoning structure composed of feldspar-rich zones enveloping pockets of mica(mostly muscovite) and all zoning internal quartz ***,the monzogranite and granitic pegmatites are composed of potash-feldspar,albite,and quartz with a small amount of biotite and *** mineralogical investigation of the highly radioactive zones in the granitic pegmatite shows enrichment in kasolite,uranothorite,thorite,xenotime,columbite,zircon,bismuth,and ***,the granitic pegmatites are enriched with high field strength elements(HFSE;Zr,Nb,Th,and U) and ion lithophilic elements(LILE;Rb,and Pb) and depleted in Ba,Sr,and *** are strongly peralkaline to metalumainous except for two samples,which are *** are formed by partial melting of metagreywackes at *** studied granitic pegmatites could belong to the NYF family(Niobium-Yttrium-Fluorine family) according to the geochemistry of the trace *** studied granitic pegmatites show deep negative Eu anomaly and display a strong m-type tetrad effect of rare earth *** field spectroscopy measurements showed the localization of the radiometric anomalous associated with the granitic pegmatites,which are intruded in the granitic host *** eU and eTh contents reached up to 316 and 1367 ppm,*** and thorium occurrences in the investigated granitic pegmatites are related to magmatic(syngenetic)ori

关键词： Geochemistry Gabal Um Lassaf-Abu Dob-Um Atelia-Kadabora-Kab El Rakeb area(LDAKK) Uranium REE Egypt

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Genesis of nanocrystalline Ho_2O_3 via thermal decomposition of holmium acetate: Structure evolution and electrical conductivity properties

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Journal of Rare Earths 2019年第2期37卷 185-192页

作者： bahaa m.Abu-Zied Abdullah m.Asiri Center of Excellence for Advanced materials Research (CEAmR) King Abdulaziz University Chemistry Department Faculty of Science King Abdulaziz University Chemistry Department Faculty of Science Assiut University

This study focuses on the preparation of nanostructured holmium oxide via the decomposition of holmium acetate precursor utilizing the non-isothermal strategy. Thermogravimetric analysis(TGA) was used to follow up the various thermal events involved in the decomposition process. Dehydration completes approximately at 150℃, which is followed by the decomposition of the anhydrous acetate leading to the formation of holmium oxide. Based on the TGA results the acetate precursor was heated non-isothermally at the temperature range of 150 e700℃. The obtained solids were characterized using powder X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS), Fourier transform infrared spectroscopy(FT-IR), field-emission scanning electron microscopy(FE-SEm) and transmission electron microscopy(TEm). It is found that nanocrystalline Ho_2 O_3 starts to form at 500℃ and presents the only phase detected at the 500 e700℃ range. The electrical conductivity of the solids that form at the temperature range of 300 e700℃ was investigated. The obtained values were correlated with the observed structural modifications accompanying the heat treatment. The electrical conductivity of the Ho_2 O_3 samples prepared at 500, 600 and 700℃ reaches the values of 1.92 × 10^(-7), 1.61 × 10^(-7) and 8.33 × 10^(-8) Ω^(-1)cm^(-1) at a measuring temperature of 500℃, respectively. These values are potentially advantageous for high-resistivity devices.

关键词： Nanocrystalline Ho2O3 Thermal decomposition Ho2O3 Holmium oxide Rare earth oxides Nanomaterials

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Synthesis of Dy_2O_3 nanoparticles via hydroxide precipitation: effect of calcination temperature

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Journal of Rare Earths 2014年第3期32卷 259-264页

作者： bahaa m.Abu-Zied Abdullah m.Asiri Chemistry Department Faculty of Science King Abdulaziz University Center of Excellence for Advanced materials Research (CEAmR) King Abdulaziz University Chemistry Department Faculty of Science Assiut University

This work described the preparation of dysprosium oxide, Dy203, nanoparticles using the homogeneous precipitation method. Dy3＋ ions were precipitated using NaOH solution. The obtained product was filtered, dried, and then calcined for 1 h at the temperature range of 300-700 ℃ in static air. The calcination temperature of the Dy-precttrsor was chosen based on its decomposi- tion as indicated by the TGA analysis. The crystalline structure and surface morphology of the calcined solids were studied by X-ray diffraction （XRD）, field emission scanning electron microscopy （FE-SEm）, transmission electron microscopy （TEm） and X-ray pho- toelectron spectroscopy （XPS）. The obtained results revealed that Dy203 with crystallites size of 11-21 nm was formed at 500 ℃. Such value increased to 25-37 nm for the sample calcined at 700 ℃.

关键词： nanocrystalline dysprosium oxide Dy203 precipitation method Dy203 nanoparticles rare earths

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Nonlinear dynamical wave structures of Zoomeron equation for population models

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Chinese Physics B 2022年第6期31卷 235-240页

作者： Ahmet Bekir emad H m Zahran Neighbourhood of Akcaglan Imarli StreetNumber:28/426030EskisehirTurkey Departments of mathematical and Physical Engineering Benha UniversityFaculty of EngineeringShubraEgypt

The nonlinear dynamical exact wave solutions to the non-fractional order and the time-fractional order of the biological population models are achieved for the first time in the framwork of the Paul-Painlevéapproach method(PPAm).When the variables appearing in the exact solutions take specific values,the solitary wave solutions will be easily *** realized results prove the efficiency of this technique.

关键词： (2+1)-dimensional non-fractional Zoomeron equation time-fractional biological population model Paul-Painlevéapproach method traveling wave solutions

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Fabrication,characterization,and electrical conductivity properties of Pr_6O_(11) nanoparticles

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Journal of Rare Earths 2013年第7期31卷 701-708页

作者： bahaa m.Abu-Zied Youssef A.mohamed Abdullah m.Asiri Chemistry Department Faculty of ScienceKing Abdulaziz UniversityP.O.Box 80203Jeddah 21589Saudi Arabia Chemistry Department Faculty of ScienceAssiut University71516 AssiutEgypt Center of Excellence for Advanced materials Research(CEAmR) King Abdulaziz UniversityP.O.Box 80203Jeddah 21589Saudi Arabia

PrrOll nanoparticles were obtained by subsequent thermal decomposition of the as-prepared precipitate formed under ambient temperature and pressure using NaOH as precipitant. The calcination process was affected, for 1 h in static air atmosphere, at 400-700 ℃ temperature range. The different samples were characterized using X-ray diffraction （XRD）, transmission electron microscopy （TEm）, field emission scanning electron microscopy （FE-SEm）, thermogravimetric analysis （TGA）, in situ electrical conductivity, and N2 adsorption/desorption. The obtained results demonstrated that nano-crystalline Pr6O11, with crystallites size of 6-12 nm, started to form at 500 ℃. Such value increased to 20-33 nm for the sample calcined at 700℃. The as-synthesized PrrOll nanoparticles presented high electrical conductivity due to electron hopping between Pr（III）-Pr（IV） pairs.

关键词： nanocrystalline praseodymium oxide Pr6O11 nano structured materials electrical conductivity rare earths

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Robust malicious Executable Detection Using Host-Based machine Learning Classifier

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Computers, materials & Continua 2024年第4期79卷 1419-1439页

作者： Khaled Soliman mohamed Sobh Ayman m.bahaa-Eldin Department of Computer and Systems Engineering Ain Shams UniversityCairo11517Egypt Department of Computer Engineering Technology ElSewedy University of TechnologyCairo44629Egypt

The continuous development of cyberattacks is threatening digital transformation endeavors worldwide and leadsto wide losses for various organizations. These dangers have proven that signature-based approaches are insufficientto prevent emerging and polymorphic attacks. Therefore, this paper is proposing a Robust malicious ExecutableDetection (RmED) using Host-based machine Learning Classifier to discover malicious Portable Executable (PE)files in hosts using Windows operating systems through collecting PE headers and applying machine learningmechanisms to detect unknown infected files. The authors have collected a novel reliable dataset containing 116,031benign files and 179,071 malware samples from diverse sources to ensure the efficiency of RmED *** most effective PE headers that can highly differentiate between benign and malware files were selected totrain the model on 15 PE features to speed up the classification process and achieve real-time detection formalicious executables. The evaluation results showed that RmED succeeded in shrinking the classification timeto 91 milliseconds for each file while reaching an accuracy of 98.42% with a false positive rate equal to 1.58. Inconclusion, this paper contributes to the field of cybersecurity by presenting a comprehensive framework thatleverages Artificial Intelligence (AI) methods to proactively detect and prevent cyber-attacks.

关键词： Portable executable malware intrusion detection cybersecurity zero-day threats Host IntrusionDetection System(HIDS) machine learning Anomaly-based Intrusion Detection System(AIDS) deep learning

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Predicting the impacts of climate change on the distribution of moringa peregrina(Forssk.)Fiori-A conservation approach

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Journal of mountain Science 2021年第5期18卷 1235-1245页

作者： emad A.FARAHAT Aliaa m.REFAAT Botany and microbiology Department Faculty of ScienceHelwan UniversityCairo 11795Egypt Botany Department Faculty of ScienceAin Shams UniversityCairo 11566Egypt

Climate change will affect the geographic distribution and richness of species at different spatial and temporal *** applied maximum entropy(maxEnt)modeling to predict the potential influence of climatic change on the current and future distribution of the important mountainous tree species moringa peregrina(Forssk.)*** maxent model performed better than random models for the species with the training and test AUC(Area Under the receiver-operating characteristic Curve)values of 0.96 and 0.90,*** test and response curves showed that the distribution of the species negatively correlates with higher altitudes and precipitation in October and ***,it positively correlates with the total annual precipitation and precipitation in *** current and future climatic conditions,our model predicted habitat gains for *** towards the coastal northern and southern limits of its *** potentially suitable habitats,under future climate projections,are currently characterized by elevations ofm *** total annual precipitation of 80-225 mm/*** and high potential habitat suitability will increase by 5.6%-6%and 2.1%-2.3%,under RCP2.6 and RCP4.5 scenario,*** results indicated that the habitat suitability of *** would increase with increasing climate warming,particularly under RCP2.6 *** recommend sustainable conservation and cultivation of moringa peregrina in its current habitats along the Red Sea mountains.

关键词： Climate change Conservation max Ent mountains moringa peregrina Arid lands

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membrane Fouling in microfiltration of Sanitary Landfill Leachate for Removals of Colourand Solids

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应用与环境生物学报 2013年第1期19卷 184-188页

作者： emad S.m.Ameen Water Research Alliance Institute of Environmental and Water Resource ManagementFaculty of Civil EngineeringUniversiti Teknologi Malaysia

In this research,the treatability of solids from sanitary landfill leachate by microfiltration membrane was investigated and the fouling of the membrane was carefully *** microfiltration process was carried out for 21 h in experimental system involved coagulation with moringa oleifera followed by filtration using submerged hollow fibre microfiltration membrane (mFm).Coagulation with ***,air diffusers and back flush technique were used for preventing or alleviating fouling of the *** hollow fibre mFm showed high removals of 98%,91% and 99% for turbidity,colour and total suspended solids *** was obtained at the beginning of the ***,quality of the filtrate rapidly declined during the filtration *** was found to proceed according to the classical cake filtration *** with *** as well as the back-flush technique could not fully restore the deterioration occurred to the membrane.

关键词： RAPD ISSR AFLP 环境生物学

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碱促进的钴酸镁催化剂上的氧化亚氮分解(英文)

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催化学报 2011年第2期32卷 264-272页

作者： bahaa m. ABU-ZIED Chemistry Department Faculty of ScienceAssiut University

The direct decomposition of N2O was investigated over a series of magnesium cobaltite catalysts,mgxCo1-xCo2O4(0.0 ≤ x ≤ 1.0) ,which were prepared by the thermal decomposition of stoichiometric amounts of magnesium hydroxide and cobalt acetate. The thermal genesis of the different catalysts from their precursors was explored using thermogravimetric analysis,differential thermal analysis,and X-ray diffraction. Texture analysis was carried out using N2 adsorption at -196 °C. We found that all the catalysts that were calcined at 500 °C have a spinel structure. N2O decomposition activity was found to increase with an increase in the spinel structure's magnesium content. The influence of alkali cation promoters(Li,Na,K,and Cs) on the activity of the most active catalyst in the mgxCo1-xCo2O4 series,i.e. mgCo2O4,was also investigated. The sequence of the promotional effect was found to be: un-promoted moted catalyst. The reason for the increase in activity for the added alkali cations was electronic in nature. Additionally,the dependence of the activity on the K/Co ratio was also determined. The highest activity was obtained for the catalyst with a K/Co ratio of 0.05. A continuous decrease in activity was obtained for higher K/Co ratios. This decrease in activity was attributed to the elimination of mesoporosity in the catalysts with K/Co ratios > 0.05,based on N2 adsorption and scanning electron microscopy results.

关键词： nitrous oxide cobalt oxide magnesium cobaltite spinel alkali promotion

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