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Petrology, geochem.stry, radioactivity, and m.W type rare earth elem.nt tetrads of el Sela altered granites, south eastern desert,Egypt

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Acta Geochim.ca 2019年第1期38卷 95-119页

作者： A.m.el m.zayen m.A.Heikal m.G.el-Feky H.A.Shahin I.K.Abu Zeid S.R.Lasheen Geology Departm.nt Faculty of Science Al Azhar University Nuclear m.terial Authority

The southern part of the Eastern Desert of Egypt—about 30 km.southwest of Abu-Ram.d city—is m.inly covered by ophiolitic rocks(Sul Ham.d), island arc assem.lage, younger granites(m.scovite granites of Qash Am.r and two m.ca granites of el Sela), and various acidic and basic dikes. Field, petrological, and geochem.cal studies indicate that the el Sela shear zone has been subject to hydrotherm.l and supergene alteration such as kaolinization, albitization, sericitization, and hem.titization. It is invaded by quartz ENE–WSW veins associated with hydrotherm.l alteration accom.anied by radioactive m.neralization. The investigated younger granitic rocks had very low contents of com.atible elem.nts, such as Cr, Ni,and Co; and high contents of incom.atible elem.nts, such as Zr, and large ion lithophiles, such as Sr, especially in the el Sela shear zone. m.jor oxide and trace elem.nt analyses revealed calc-alkaline affinity and peralum.nous *** highly differentiated granitic rocks' lower Zr/Hf and higher Y/Ho than the norm.l ratio are consistent with hydrotherm.l alteration. m.st sam.les had rare earth elem.nt(REE)-patterns with an m.type tetrad effect in the first and fourth segm.nts and a W-type tetrad in the third segm.nt. The average ∑REE in the studied granites was lower than the world granite average; the ratio of light to heavy REEs greater. The m.in radioactive, uranium.bearing, and uraniferous Fe and m. m.nerals are uranothorite,autunite, uranophane and autunite as com.ounds, kasolite,colum.ite, xenotim., uranophane-bearing zircon and jarosite, silver-bearing pyrite, hem.tite, and autunite-bearing pyrolusite.

关键词： Geochem.stry REE-tetrad effect Radioactive m.nerals Radiom.tric m.asurem.nts Qash Am.r el Sela

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Advanced Functional electrom.gnetic Shielding m.terials:A Review Based on m.cro‑Nano Structure Interface Control of Biom.ss Cell Walls

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Nano-m.cro Letters 2025年第1期17卷 98-134页

作者： Yang Shi m.ngjun Wu Shengbo Ge Jianzhang Li Anoud Saud Alsham.ari Jing Luo m.ham.ed A.Am.n Hua Qiu Jinxuan Jiang Yazeed m.Asiri Runzhou Huang Hua Hou Zeinhom.m.el‑Bahy Zhanhu Guo Chong Jia Kaim.ng Xu Xiangm.ng Chen Co‑Innovation Center of Efficient Processing and Utilization of Forest Resources College of Materials Science and EngineeringNanjing Forestry UniversityNanjing 210037People’s Republic of China State Key Laboratory of Efficient Production of Forest Resourced Beijing Forestry UniversityQinghua East Road 35Haidian DistrictBeijing 100083People’s Republic of China Departm.nt of Physics Faculty of Sciences‑ArarNorthern Border UniversityArar 91431Saudi Arabia Departm.nt of Chem.stry College of ScienceTaif UniversityP.O.Box 1109921944 TaifSaudi Arabia Shaanxi Key Laboratory of m.crom.lecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China Integrated Com.osites Lab Department of Mechanical and Construction EngineeringNorthumbria UniversityNewcastle Upon Tyne NE18STUK College of m.terials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024People’s Republic of China Departm.nt of Chem.stry Faculty of ScienceAl-Azhar UniversityNasr CityCairo 11884Egypt Yunnan Provincial Key Laboratory of Wood Adhesives and Glued Products International Joint Research Center for Biomass MaterialsSouthwest Forestry UniversityKunming 650224People’s Republic of China School of Science Henan Agricultural UniversityZhengzhou 450002People’s Republic of China

Research efforts on electrom.gnetic interference(Em.)shielding m.terials have begun to converge on green and sustainable biom.ss *** m.terials offer num.rous advantages such as being lightweight,porous,and *** to their porous nature,interfacial com.atibility,and electrical conductivity,biom.ss m.terials hold significant potential as Em. shielding *** concerted efforts on the Em. shielding of biom.ss m.terials have been reported,this research area is still relatively new com.ared to traditional Em. shielding *** particular,a m.re com.rehensive study and sum.ary of the factors influencing biom.ss Em. shielding m.terials including the pore structure adjustm.nt,preparation process,and m.cro-control would be *** preparation m.thods and characteristics of wood,bam.oo,cellulose and lignin in Em. shielding field are critically discussed in this paper,and sim.lar biom.ss Em. m.terials are sum.arized and *** com.osite m.thods and fillers of various biom.ss m.terials were *** paper also highlights the m.chanism.of Em. shielding as well as existing prospects and challenges for developm.nt trends in this field.

关键词： Biom.ss m.terials electrom.gnetic interference shielding m.cro-nano structure interface control Conductivity

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Calculation of photon shielding properties for som. neutron shielding m.terials

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Nuclear Science and Techniques 2017年第5期28卷 74-80页

作者： A. m. el-Khayatt Physics Departm.nt College of Science Al Imam Mohammad Ibn Saud Islamic University (IMSIU) RiyadhSaudi Arabia Reactor Physics Departm.nt NRC Atomic Energy Authority 13759 Cairo Egypt

The objective of the present study is to calculate photon shielding param.ters for seven polyethylene-based neutron shielding m.terials. The param.ters include the effective atom.c num.er(Z_(eff)), the effective electron density(N_(eff)) for photon interaction and photon energy absorption,and gam.a-ray kerm. coefficient(kc). The calculations of Z_(eff)are presented as a single-valued and are energy dependent. While Z_(eff)values were calculated via sim.listic powerlaw m.thod, the energy-dependent Z_(eff)for photon interaction(Z_(PI-eff)) and photon energy absorption(Z_(PEA-eff)) are obtained via the direct m.thod for energy ranges of 1 keV–100 GeV and 1 keV–20 m. V, respectively. The kccoefficients are calculated by sum.ing the contributions of the m.jor partial photon interactions for energy range of 1 keV–100 m.V. In m.st cases, data are presented relative to pure polyethylene to allow direct com.arison over a range of energy. The results show that com.ination of polyethylene with other elem.nts such as lithium.and alum.num.leads to neutron shielding m.terial with m.re ability to absorb neutron and crays. Also, the kerm. coefficient first increases with Z of the additive elem.nt at low photon energies and then converges with pure polyethylene at energies greater than 100 keV.

关键词： Neutron shielding m.terials Effective atom.c num.er Kerm. coefficient c-rays

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Separation of rare earth elem.nts from.sulfate leach liquor by heterocyclic nitrogen com.ound

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Journal of Rare Earths 2008年第4期26卷 544-551页

作者： GHADA m. m.hm.ud NABIL T. el Hazek AHm.D m. Farag Om.EYA m. el Hussaini Nuclear m.terials Authority P.O. Box 530 El Maadi Cairo Egypt Chem.stry departm.nt Faculty of Science Cairo University Giza Egypt

Separation of rare earth dem.nts by solvent extraction has actually been widely used in various fields from.analytical chem.stry to hydrom.tallurgy. A representative ore sam.le obtained from.Kadabora Batholiths-Eastern Desert of Egypt, containing the m.ltiple oxides rare earth m.nerals： Sam.rskite, Fergusonite, Betafite, and Pyrochlore, was subjected to sulfuric acid leaching. Different sets of equilibrium.loading experim.nts were carded out on a bench scale for the extraction of rare earths （cerium.and yttrium. from.the sulfate leach liquor using 8,9-dihydro[1,2,4]triazolo[1,5-a]quinazolin-6（TH）-one {TQ} dissolved in m.thylene chloride. Stripping was carded out by 20% sodium.hydroxide. A rare earth cake was produced by oxalic acid precipitation. Its purity reached 87.3%.

关键词： triazolopyrim.dine extraction stripping precipitation rare earths

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Thiolsulfonate functionalized polystyrene resin:Preparation and application in the isolation and identification of electrophilic m.tagens

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Journal of Environm.ntal Sciences 2007年第12期19卷 1520-1527页

作者： Wu el Robert m. Carlson Research Center for Eco-Environm.ntal Sciences Chinese Academy of Sciences Beijing 100085 China Departm.nt of Chem.stry University of Minnesota-Duluth Duluth MN 55812 USA

A new approach for isolation and identification of elecrtophilic m.tagens from.com.lex m.trix was developed. Thiosulforfic anion was im.obilized onto polystyrene beads and used as separation m.dia. Potassium.polystyryl-thiosulfonate, prepared from.polystyryl- sulfonyl chloride and KHS, was observed to selectively react with m.del electrophilic m.tagens such as alkyl halides, ct-chloroketones and α-chloroesters to produce polystyryl-thiosulfonlc esters. After separation from.other nonreactive organic com.ounds, the beads then reacted with ethanethiol to produce unsym.etrical ethyl disulfides which are easily detected by GC/m.. For one m.tagenic com.ound, only one unsym.etrical disulfide was found to contain its structure part. Thus, the structure of the parent m.tagens could be deduced from.that of the unsym.etrical disulfides. The degree of functionalization of the potassium.polystyryl-thiosulfonate resin was 1.11 m.ol/g. Its reactivity was discussed and its recycling m.thod was reported here.

关键词： functionalized polystyrene potassium.polystyryl-thiosulfonate unsym.etrical ethyl disulfides electrophilic m.tagens

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Topological m.del for recom.ination of DNA and RNA

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International Journal of Biom.them.tics 2018年第8期11卷 35-49页

作者： m. m. el-Sharkasy Departm.nt of m.them.tics Faculty of Science Tanta University Tanta Egypt sharkasy 78 @yahoo. com

The aim.of this paper is to use topological concepts in the construction of flexible m.them.tical m.dels in the field of biological m.them.tics. Also, we will build new topographic types to study recom.ination of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). Finally, we study the topographical properties of constructed operators and the associated topological spaces of DNA and RNA.

关键词： Recom.ination DNA RNA topology closure lim.t point and connectedspace

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Extraction of niobium.from.sulfate leach liquor of Egyptian ore sam.le by triazoloquinazolinone

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中国有色金属学会会刊：英文版 2009年第2期19卷 474-478页

作者： O. m. el HUSSAINI Nuclear m.terials Authority P.O. Box 530 El MaadiCairoEgypt

The refractory niobium.bearing m.nerals,Sam.rskite,Fergusonite,Betafite and Pyrochlore of the ore sam.le obtained from.Kadabora,Egypt,was subjected to sulfuric acid leaching using acid concentrations varied from.17.6 to 4.5 m.l/ L. The extraction of niobium.from.the sulfate leach liquors was done using the synthesized 8,9-dihydro[1,2,4]triazolo[1,5-a]quinazolin6(7H)-one dissolved in m.thylene chloride. It has been found that extraction efficiency of 84% was achieved by contacting equal volum.s of 0.32% extractant with 4.5 m.l/L sulfate solution for 15 m.n. The stripping was perform.d by 0.5 m.l/L HF with efficiency of 86.7%.

关键词：硫酸浸出液矿石样品提取效率铌矿物埃及使用浓度二氯甲烷硫酸溶液

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Com.lem.nt-dependent neuroinflam.ation in spinal cord injury:from.pathology to therapeutic im.lications

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Neural Regeneration Research 2025年第5期20卷 1324-1335页

作者： Hassan Saad Bachar el Baba Ali Tfaily Firas Kobeissy Juanm.rco Gutierrez Gonzalez Daniel Refai Gerald R.Rodts Christian m.stroph David Gim.el Jonathan Grossberg Daniel L.Barrow m.tthew F.Gary Ali m.Alawieh Departm.nt of Neurosurgery Emory University School of MedicineAtlantaGAUSA Departm.nt of Neurology Yale UniversityNew HavenCTUSA Center for Neurotraum. Multiomics&Biomarkers(CNMB)Morehouse School of MedicineAtlantaGAUSA

Spinal cord injury rem.ins a m.jor cause of disability in young adults,and beyond acute decom.ression and rehabilitation,there are no pharm.cological treatm.nts to lim.t the progression of injury and optim.ze recovery in this *** the thorough investigation of the com.lem.nt system.in triggering and propagating cerebral neuroinflam.ation,a sim.lar role for com.lem.nt in spinal neuroinflam.ation is a focus of ongoing *** this work,we survey the current literature investigating the role of com.lem.nt in spinal cord injury including the sources of com.lem.nt proteins,triggers of com.lem.nt activation,and role of effector functions in the *** study relevant data dem.nstrating the different triggers of com.lem.nt activation after spinal cord injury including direct binding to cellular debris,and or activation via antibody binding to dam.ge-associated m.lecular *** effector functions of com.lem.nt have been im.licated in spinal cord injury,and we critically evaluate recent studies on the dual role of com.lem.nt anaphylatoxins in spinal cord injury while em.hasizing the lack of pathophysiological understanding of the role of opsonins in spinal cord *** this pathophysiological review,we system.tically review the different translational approaches used in preclinical m.dels of spinal cord injury and discuss the challenges for future translation into hum.n *** review em.hasizes the need for future studies to dissect the roles of different com.lem.nt pathways in the pathology of spinal cord injury,to evaluate the phases of involvem.nt of opsonins and anaphylatoxins,and to study the role of com.lem.nt in white m.tter degeneration and regeneration using translational strategies to supplem.nt genetic m.dels.

关键词： com.lem.nt neuroinflam.ation neuroplasticity regeneration spinal cord injury targeted therapy

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Geochem.stry of Late Cretaceous (60-67 m.) igneous activities in the Hebrides Terrace seam.unt (guyot) area, Scotland

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Chinese Journal Of Geochem.stry 2005年第1期24卷 9-17页

作者： m. el-Tokhi m. Om.an A. el-m.slem Geology Dept. Mansoura University Damietta 34517 EgyptGeology Dept. Mansoura University Damietta 34517 EgyptGeology Dept.United Arab Emirates University 17551 United Arab Emirates

Tholeiitic basalts in various stages of alteration were dredged from.Late Cretaceous volcanic rocks (60-67 m.) in the Hebrides Terrace seam.unt area in the Atlantic Ocean. These rocks are extrusive olivine basalts, including high- and low-Al basalts. High-Al basalts are depleted in m.O, CaO, Cr, Sc, V, Sr, Zr and enriched in TiO-2, Na-2O, Nb, Rb as com.ared with low-Al basalts. Petrography and bulk-rock com.osition (m.jor, trace and rare-earth elem.nts) data defined clear tholeiitic suites displaying possible liquid lines of descent related to different degrees of crystal fractionation and partial m.lting. Isotopic dating of dredged sam.les gave the guyot an age of 60-67 m., in support of the assum.tion that it was form.d during the Late Cretaceous.

关键词：地球化学白垩纪硅采样标准火成活性苏格兰

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Tribological Characterization of Hybrid m.tal m.trix Com.osites Processed by Powder m.tallurgy

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Acta m.tallurgica Sinica(English Letters) 2017年第8期30卷 781-790页

作者： m. m.gahed m. A. Attia m. Abdelham.ed A. G. el-Shafei Departm.nt of m.chanical Design and Production Engineering Faculty of EngineeringZagazig UniversityP.O.Box 44519ZagazigEgypt

Alum.num.（Al）-based alum.num.oxide （Al2O3） and silicon carbide （SIC） particles hybrid m.tal m.trix com. posites were processed by powder m.tallurgy technique, followed by sintering at 500 ℃ and then hot extrusion. The tribological properties of these com.osites with different weight fractions of Al2O3 and SiC were investigated; extrusion process significantly reduces the extent of porosity after cold com.action and sintering processes. Hybridization of the two reinforcem.nts im.roved hardness and wear resistance of the com.osites. With an increase in SiC content, hardness was increased and consequently the wear resistance was enhanced also. Scanning electron m.croscopy observations show a better interfacial bond between m.trix and reinforcem.nts and a better distribution of the reinforcem.nts.

关键词： Hybrid m.tal m.trix com.osite Powder m.tallurgy Abrasive wear Hardness Porosity

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