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Rare metal-bearing pegmatites from the Southeastern Desert of Egypt:Geology,geochemical characteristics,and petrogenesis

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Chinese Journal Of Geochemistry 2007年第1期26卷 8-22页

作者： Gehad m.saleh Nuclear materials Authority P.O.Box:530 El-MaadiCairoEgypt

The pegmatite province of the Southeastern Desert (SED) is part of a pegmatite district that extends from Egypt (extends to 1200 km2). Rare metal pegmatites are divided into (1) unzoned, Sn-mineralized; (2) zoned Li, Nb, Ta and Be-bearing; and (3) pegmatites and pegmatites containing colored, gem-quality tourmaline. The Rb/Sr data reflect a crustal origin for the rare metal pegmatites and indicate that the original SED magma was generated during the peak of regional metamorphism and predates the intrusion of post-tectonic leucogranites. These bodies developed an early border zone consisting of coarse to very coarse muscovite+quartz+alkali feldspar, followed by an intermediate zone of dominant quartz+feldspar+muscovite rock. Garnet, tourmaline, beryl, galena, pyrite, amblygonite, apatite and monazite are rare accessories in both zones. Cassiterite tends to concentrate in replacement zones and along fractures in albite+quartz+muscovite-rich portions. The highest concentrations of cassiterite occur in irregular greisenized zones which consist dominantly of micaceous aggregates of green Li-rich muscovite, quartz, albite and coarse-grained cassiterite. The different metasomatic post-solidification alterations include sodic and potassic metasomatism, greisenization and tourmalinization. Geochemically, the pegmatite-generating granites have a metaluminous composition, showing a differentiation trend from coarse-grained, unfractionated plagioclase-rich granite towards highly fractionated fine- to medium-grained, local albite-rich rock. Economically important ore minerals introduced by volatile-rich, rare metal-bearing fluids, either primarily or during the breakdown of the primary mineral assemblages, are niobium-tantalum oxides, Sn-oxides (cassiterite), Li-silicates (petalite, spodumene, euctyptite, and pollucite), Li-phosphates (amblygonite, montebrasite and lithopilite) and minor REE-minerals (Hf-zircon, monazite, xenotime, thorian, loparite and yttrio-fluorite). The pol

关键词：埃及东南部沙漠稀有金属伟晶岩地质地球化学特征岩石成因

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

Synthesis and spectroscopic characterization of novel 2-amino-4,5,6,7-tetrahydro-3H-cyclopenta[d]pyrimidine and pyrimido[1,2-α]pyrimidine derivatives

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Chinese Chemical Letters 2015年第6期26卷 690-694页

作者： mohamed S.A.El-Gaby Jehan A.micky Nadia m.saleh Yousry A.Ammar Heba S.A.mohamed Chemistry Department Faculty of ScienceAl-Azhar University at Assiut Chemistry Department Faculty of Science (Girl’s)Al-Azhar University Chemistry Department Faculty of ScienceAl-Azhar University Photochemistry Department National Research CenterEl-DokkiGizaEgypt

2-Aminocyclopenta[d]pyrimidines 3a-c were achieved via a one-pot, three-component reactions of cyclopentanone 1, aromatic aldehyde and guanidine hydrochloride （1：2：1 molar ratio）. Also, cyclization of 2,5-bis-（arylmethylidene）cyclopentanones 2 with guanidine hydrochloride （1：1 molar ratio） in methanol in the presence of sodium methoxide afforded cyclopenta-[d]pyrimidines 3. Compound 3c has been shown to be a useful building block for the synthesis of some novel pyrimido[ 1,2-a]pyrimidines 5, 7 and 12. The structures of the newly synthesized compounds were confirmed on the basis of analytical and spectral data,

关键词： multicomponent reaction Cyclopenta[d]pyrimidine Pyrimido[1 2-a]pyrimidine Cyclopentanone

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6016铝合金的电磁驱动机械锤击平整加工

表面技术 2020年第3期49卷 334-339页

作者：林晓辉杨帆陈博伦刘建春 m.saleh 厦门理工学院机械与汽车工程学院福建厦门361024

目的探究机械锤击平整加工对提高铝合金表面完整性和硬度的作用效果,研究锤击参数对平整表面质量的影响规律。方法采用电磁驱动机械锤击技术对6016铝合金进行平整加工,研究基于光栅路径的电磁驱动机械锤击加工机理,并提出主要锤击参数,... 详细信息

目的探究机械锤击平整加工对提高铝合金表面完整性和硬度的作用效果,研究锤击参数对平整表面质量的影响规律。方法采用电磁驱动机械锤击技术对6016铝合金进行平整加工,研究基于光栅路径的电磁驱动机械锤击加工机理,并提出主要锤击参数,进而分析主要锤击参数对平整表面质量的影响规律。利用泰勒霍普生轮廓仪、光学显微镜和维氏硬度仪分别获得机械锤击后铝合金的表面粗糙度、表面形貌以及硬度。结果电磁驱动机械锤击后,铝合金表面粗糙度达到0.05μm,获得了类似镜面的锤击表面。相对于铣削后的表面,机械锤击可消除铣削痕迹,没有明显的表面缺陷和划痕,具有良好的表面平顺能力,同时硬度可提升大约25%~32%。小节距和进给速度、高锤击频率有助于减小表面粗糙度和提高硬度。此外,节距是最重要的锤击参数,极大地影响表面粗糙度和加工效率。结论电磁驱动机械锤击对6016铝合金具有很好的表面强化和平整能力,可大幅减小表面粗糙度,并适当提高表面硬度,是一种新颖、有效、绿色的平整方式。

关键词： 6016铝合金机械锤击锤击参数表面粗糙度表面形貌硬度

Neurocysticercosis:A case report and brief review

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Asian Pacific Journal of Tropical medicine 2016年第1期9卷 98-100页

作者： Syed A.A.Rizvi Ayman m.saleh Hanns Frimpong Hussain m.Al mohiy Jasmin Ahmed Ronda D.Edwards Sultan S.Ahmed College of Pharmacy Nora Southeastern University JAS medical management LLC Department of Basic medical Sciences College of MedicineKing Saud Bin Abdulaziz University for Health SciencesNational Guard Health Affairs Radiological Sciences Department College of Applied Medical SciencesKing Khalid University Herbert Wertheim College of medicine Florida International University School of medicine Spartan Health Science University

Neurocysticercosis(NCC) is one of the seven neglected endemic zoonoses targeted by the World Health *** is considered a common infection of the nervous system caused by the Tanenia solium and is known to be the primary cause of preventable epilepsy in many developing *** is commonly resulted by the ingestion of Tanenia solium eggs after consuming undercooked pork,or contaminated *** parasite can grow in the brain and spinal cord within the nervous system,causing severe headache and seizures beside other pathological *** and international travel to endemic countries has made this disease common in the United *** can be diagnosed with computed tomography and magnetic resonance imaging of the *** treatment of the NCC including cysticidal drugs(eg.,albendazole and praziquantel),and neurosurgical procedure,depending upon a the situation.A patient of Asian origin came to our clinic with complaints of dizziness,headaches and episodes seizures for the past twelve years without proper *** computed tomography and magnetic resonance imaging scans indicated multilobulated cystic mass in the brain with the suspicion of neurocysticercosis.

关键词： Neurocysticercosis Tanenia solium Epilepsy magnetic resonance imaging Computed Tomography

Origin and geochemical characteristics of beryllium mineralization in the Zabara-Wadi El Gemal region,South Eastern Desert,Egypt

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Acta Geochimica 2024年第6期43卷 1105-1122页

作者： Gehad m.saleh Farrage m.Khaleal mohammed Z.El-Bialy mohamed S.Kamar mokhles K.Azer mohamed m.Omar mohamed N.El Dawy Ahmed Abdelaal El Saeed R.Lasheen Nuclear materials Authority El-MaadiP.O.Box 530CairoEgypt 2 Geology DepartmentFaculty of SciencePort Said UniversityPort Said 42522Egypt 3 Geological Sciences DepartmentNational Research CentreCairoEgypt 4 Environmental Sciences DepartmentFaculty of SciencePort Said UniversityPort Said 42522Egypt 5 Geology DepartmentFaculty of ScienceAl-Azhar UniversityP.O.Box 11884CairoEgypt

Beryl is the commercial source of beryllium and several varieties of it are valued as a *** contribute to understanding the mechanism of beryl formation,we carried out detailed geological,petrographical,and geochemical investigations on beryl mineralization occurrences in the Zabara-Wadi El Gemal(Z-WG)*** region is an NW-SE trending tract that includes six berylhosting *** green gem variety of beryl(emerald)is restricted to phlogopite schist,pegmatite,and quartz *** hexagonal emerald crystals are well-developed in phlogopite schist and *** gem variety emerald examined is sodic and *** contains high concentrations of chromophore transition elements ordering Cr(up to 1511 ppm)>V(up to 242 ppm)>Sc(up to 245 ppm),giving rise to its vivid green color,refl ecting mafic-ultramafic source *** the investigated emeralds,the Sikait area contains the highest BeO(av.10.76wt.%)*** compositional variability of emeralds is most likely attributed to the contribution from the host *** is revealed by the examined emerald mineralization,for instance;the Abu Rusheid area(one of the best areas exposing rare metal-bearing granitoids)possesses the highest average of trace and REEs *** contrast,Um Kabu emerald has the highest contents of Co(av.20 ppm),Ni(av.299 ppm),mgO(av.8.2wt.%),Fe_(2)O_(3)(av.3.12wt.%),and CaO(avg.3.4wt.%)relative to other areas,which may be linked to contribution of ultramafic rocks exposed *** proposed mechanism we suggest for emerald genesis is metasomatic interaction between felsic intrusions,that are enriched with K,Na,Be,Li,and B,with mafic-ultramafic rocks that are enriched in Cr,V,mg,Fe,and *** interaction is marked by the formation of phlogopite schist,the growth of emerald crystals,and desilicated pegmatite.

关键词： Beryl chemistry Emerald genesis Phlogopite schist Pegmatite Eastern Desert

In vitro and in vivo evaluation of the antiangiogenic activities of Trigonella foenum-graecum extracts

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Asian Pacific Journal of Tropical Biomedicine 2017年第8期7卷 732-738页

作者： Zina A.Habib-martin Hana m.Hammad Fatma U.Afifi malek Zihlif Hamzeh J.Al-Ameer mohanad m.saleh Ismail F.Abaza Zeyad D.Nassar Department of Biology School of ScienceThe University of Jordan Department of Pharmaceutical Sciences School of PharmacyThe University of Jordan Department of Pharmacology School of MedicineThe University of Jordan School of medicine and Freemasons Foundation Centre for men's Health University of Adelaide South Australian Health and medical Research Institute

Objective: To assess the antiangiogcnic activity of ***: Different fractions of fenugreek crude extracts were prepared and their antiangiogenic properties were assessed using the ex vivo rat aortic ring assay and in vivo chicken embryo chorioallantoic membrane(CAm) assay. They were investigated for their direct cytotoxic activity in the mCF7 cells using the mTT ***: The ethanol extract showed 100% inhibition of blood vessel outgrowth from primary tissue explants in the rat aortic ring assay at a concentration of 100μg/mL while the other extracts did not show significant antiangiogenic activity. The ethanol extract was therefore investigated at varying concentrations and exhibited a significant dose dependent effect. The CAm assay coincided with the results of the aortic ring assay as ethanol extract showed a significant inhibition of formation of new blood vessels. The extracts only showed anti-proliferative activity at the highest concentration of 400μg/mL towards mCF7 breast cancer cell lines in the mTT ***: Findings of the both assays confirmed that the ethanol extract inhibited vascularization significantly. Further studies on the ethanol extract would be beneficial in isolating the active ingredient responsible for the inhibition.

关键词： Fenugreek mCF7 Angiogenesis Rat aortic ring assay CAm assay mTT assay

Staphylococcal Cassette Chromosome mec(SCCmec) Gene Typing in Detection of methicillin-Resistant Staphylococcus aureus: Toward Precise Detection in Health Care Facility

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Open Journal of medical microbiology 2019年第3期9卷 127-137页

作者： Rania m.Kishk mohamed F.mandour Rania m.saleh microbiology and Immunology Department Faculty of MedicineSuez Canal UniversityIsmailiaEgypt Clinical Pathology Department Faculty of MedicineSuez Canal UniversityIsmailiaEgypt

Background: Blood stream infections (BSI) are considered key issues in critical care units. methicillin resistant Staphylococcus aureus, mRSA-related infections, are considered a major health problem. This is attributed to the emerging new society dangerous strains with continuous antibiotics pressure and fluctuations in resistance patterns. Aim: We aimed to study epidemiology of methicillin resistance S. aureus (mRSA) infections by using conventional phenotypic methods [cefoxitin disk diffusion (CDD) and oxacillin screening agar] and molecular typing of the mec-gene (SCCmec) using multiplex PCR in Suez Canal University Hospital. methods: 100 non-repetitive staphylococcus aureus were collected and identified morphologically and biochemically by standard laboratory procedures. The strains were considered mRSA if the mIC of oxacillin ≥ 4 μg/ml, and the inhibition zone of cefoxitin was ≤21 mm (CDD). Characterization of SCCmec elements in isolated mRSA strains was done via multiplex-PCR. Results: From total of 100 isolates, eighty were detected as mRSA by using CDD (sensitivity and specificity were 83.6% and 24.4% respectively) and only 65 by using oxacillin screening agar (sensitivity and specificity were 85.5% and 60% respectively). mecA gene was identified in 55 samples;the majority of isolates were SCCmec type IVa (63.7%). Both type I and III of SCCmec couldn’t be detected. Antimicrobial sensitivity rates among SCCmec-V isolates were expectedly higher than those among Type-II isolates. SCCmec type II was characterized by 100% resistant to ciprofloxacin, erythromycin, oxacillin and cefepime as well as greater resistance to clindamycin (70%) with the same pattern between all typing strains (7 strains). Conclusion: SCCmec types IVa and V are generally dominant in our community with no detection of SCCmec types I or III. PCR is the optimum method for mRSA detection.

关键词： mRSA Blood Stream Infections mecA

The chromite deposits associated with ophiolite complexes, Southeastern Desert, Egypt: Petrological and geochemical characteristics and mineralization

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Chinese Journal Of Geochemistry 2006年第4期25卷 307-317页

作者： Gehad m. saleh Nuclear materials Authority P.O.Box: 530 El Maadi Cairo Egypt

The podiform chromitites occur in a well-preserved mantle sequence consisting of lherzolite-harzburgite with abundant lenses of olivine dunite. The podiform chromitite deposits are common as small and irregularly shaped masses in the Southeastern Desert (SED) of Egypt. The podiform chromitites exhibit a wide range of compositions from high Cr to high Al varieties. The Cr of chrome spinel ranges from 0.67 to 0.88 in olivine-dunite, quite similar to that of the high-Cr chromitite, whereas it is around 0.62 in lherzolite-harzburgite. Primary hydrous mineral inclusions, amphibole and phlogopite, in chrome spinel have been reported for the first time from the Pan-African Proterozoic podiform chromitites. On the other hand, petrographic and geochemical evidence suggests that podiform chromitites in the SED of Egypt were formed as a result of crystallization of mafic melts, probably of boninitic composition, the boninitic parental magmas were probably produced by a second stage of melting above a subduction zone. Three types of chromite ores can be distinguished within the SED of Egypt: (a) sulphide-poor podiform ores; (b) brecciated ores; and (c) sulphide-rich ores. Two textural types of inclusions in chromite are distinguished: (1) primary silicate inclusions generally have high mg-number (>96), Cr and Ni, and are dominated by pargasitic amphibole, forsterite, diopside, enstatite and Na-phlogopite. A diversity of primary and secondary platinum group minerals (PGm) is described from the chromitites, including alloys, sulphides, sulpharsenides and arsenides of Ru, Os, Ir, Rh, Ni, Cu, Fe and Co; (2) in addition to primary PGm and hydrous silicates, the fluids are of low to moderate salinity, sodium-dominated aqueous solutions with complex gas contents. Variable amounts of water, hydrogen, hydrocarbons, carbon dioxides and nitrogen have been determined in inclusion-rich samples. The chondrite-normalized PGE patterns of lherzolite-harzburgite and olivine-dunite have negative

关键词：铬铁矿沉淀蛇绿岩复合物东南沙漠埃及岩石学