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Mineral Chemistry of Two-Mica Granite Rare Metals: Impact of Geophysics on the Distribution of Uranium Mineralization at el Sela Shear Zone, egypt

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Open Journal of Geology 2014年第4期4卷 137-160页

作者： Ibrahim Gaafar Michel Cuney ahmed abdel gawad G2R Nancy-Université CNRS CREGU Lorraine France Nuclear Materials Authority Cairo Egypt

The present work aims at identifying Nb-Ta-, Zr-Hf-, Ree-, Th-U-bearing two-mica granite from geological, geophysical cross-sections and mineral chemistry studies from three boreholes at G. el Sela shear zone. Microscopically, the three boreholes are composed mainly of two-mica granite. They are composed of K-feldspar, plagioclase, quartz, biotite and muscovite. Accessories are pyrite, zircon, fluorite, rutile, monazite with Th-U-mineralization identified by scanning electron microscope (SeM) and electron probe-microanalyses (ePMA). Chlorite, muscovite, sericite, kaolinite are secondary minerals. Geochemically, two-mica granite boreholes are A-type granites and peraluminous characteristics. They are enriched in large ion lithophile elements (LILe;Ba, Rb and Sr), high field strength elements (Y, Zr and Nb), and LRee but depleted in HRee with negative eu anomaly. U-enrichment associated with chloritization, muscovitization, albitization, sericitization, kaolinization and argillization results from convective hydrothermal circulation of fluids through brittle structures along the eNe-WSW main shear zone. The ratios Nb/Ta (7.7 - 17.7) and Zr/Hf (16.9 - 26.4) are relatively enriched in the lighter isovalents Ta and Hf. The accessory minerals observed in the two-mica granites are represented by metallic sulfides (pyrite, arsenopyrite, chalcopyrite, galena and sphalerite), Nb-rutile, Hf-zircon, fluorite, monazite, columbite, betafite, thorite, phosphothorite, uranothorite, brannerite, uraninite, coffinite and pitchblende at G. el Sela shear zone. Uraninite with a low Th content indicates a hydrothermal origin of U-mineralization, Thorite, uranothorite, monazite and zircon is the main uranium bearing minerals of magmatic origin within the enclosing granite. The primary U-mineralization has been observed in two boreholes. In order to illustrate the geophysical signature of el Sela U-mineralization, the radiometric, magnetic, and VLF-eM data as well as radon concentration are

关键词： Boreholes Shear Zone Radon Spectrometric Magnetic Conductivity

effect of Pd or Ir on the catalytic performance of Mo/H-ZSM-5 during the non-oxidative conversion of natural gas to petrochemicals

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Journal of Natural Gas Chemistry 2008年第4期17卷 337-343页

作者： ahmed K.Aboul-Gheit ahmed e.Awadallah Salah M.el-Kossy abdel-Lateef H.Mahmoud Process Development Division Egyptian Petroleum Research Institute Faculty of Science Department of ChemistryMNF University Ageeba Petroleum Co.

Natural gas conversion to petrochemicals, principally, benzene, naphthalene, toluene, as well as ethylene under non-oxidative conditions was examined in a fixed bed flow reactor at 700 ℃ and gaseous hourly space velocity （GHSV） of 1500 ml·g ^-1·h^-1 at time-on-stream ranging from 5 rain to 4 h using catalysts containing 6.0%Mo/H-ZSM-5 promoted with Pd or Ir metal. The catalysts were characterized by XRD, TPD, and TGA. The addition of Pd or Ir to 6%Mo/H-ZSM-5 catalyst promoted ethylene production but inhibited the cyclization reaction to aromatics owing to the strong interaction between these noble metals and the framework Al species, which were attached to the acid sites during the impregnation process. Coke deposition on the catalysts was found to decrease upon addition of 0.5wt% of Pd or Ir to 6%Mo/H-ZSM-5 catalyst owing to the hydrogenating activity of these metals.

关键词： natural gas methane benzene ethylene molybdenum Pd Ir H-ZSM-5

Rescue effects of aqueous seed extracts of Foeniculum vulgare and Carum carvi against cadmium-induced hepatic, renal and gonadal damage in female albino rats

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Asian Pacific Journal of Tropical Medicine 2017年第12期10卷 1123-1133页

作者： ahmed abdel-Wahab abdel-Razik Hashem abdel-Razik Rabie Lotfy abdel Aziz Physiology Department Faculty of Veterinary MedicineMinia University61519 El-MiniaEgypt Histology Department Faculty of Veterinary MedicineBeni-Suef University62512 Beni-SuefEgypt Department of Theriogenology Faculty of Veterinary MedicineBeni-Suef University62512 Beni-SuefEgypt

Objective: To investigate the protective effects of aqueous seed extracts of fennel"Foeniculum vulgare"(FVe) and caraway "Carum carvi"(CCe) on liver, kidney and reproductive organs in female rats against cadmium chloride(CC) ***: A total of 36 adult female rats were divided into six groups, six in each *** group(fed normal diet), CC-treated group(50 mg CC/kg diet), CCe-treated group(150 mg CCe/kg diet), CCe + CC group, FVe(150 mg/kg diet) and FVe + CC. One month later, all rats were sacrificed and all samples were collected at proestrus ***: The toxic effects of CC were confirmed biochemically by significant increase of serum concentration of liver enzymes(P eatinine(P eover,CC increased significantly the serum level of malondialdehyde(MDA) and decreased the total antioxidant capacity(TAC)(P erum concentrations of estrogen, progesterone, follicle-stimulating hormone(FSH) and luteinizing hormone(LH)were significantly decreased(P eated group revealed marked pathological changes in renal, hepatic, ovarian and uterine tissues. All toxic findings observed in liver and kidney with CC treatment were found to be ameliorated markedly after co-treatments with FVe or CCe. Furthermore, co-treatment of FVe with CC improved significantly all studied reproductive parameters(P e and CCe could be used as efficient treatments for liver and kidney against CC intoxication. Moreover, FVe could be utilized as a potent treatment to protect and improve female fertility from cadmium intoxication.

关键词： Cadmium Carum carvi Foeniculum vulgare Liver Kidney Fertility

PVC nanocomposites for cable insulation with enhanced dielectric properties,partial discharge resistance and mechanical performance

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High Voltage 2020年第4期5卷 463-471页

作者： Nagat M.K.abdel-gawad Adel Z.el Dein Diaa-eldin A.Mansour Hanaa M.ahmed Mohamed M.F.Darwish Matti Lehtonen Department of electrical Power and Machines engineering Faculty of Engineering at ShoubraBenha UniversityCairoEgypt Department of High Voltage Networks Faculty of Energy EngineeringAswan UniversityAswanEgypt High Voltage and Superconductivity Laboratory Department of Electrical Power and Machines EngineeringFaculty of EngineeringTanta UniversityTantaEgypt Department of Mathematics and engineering Physics Faculty of Engineering at ShoubraBenha UniversityCairoEgypt Department of electrical engineering and Automation School of Electrical EngineeringAalto UniversityEspooFinland

The current study aims to develop polyvinyl chloride(PVC)nanocomposites with enhanced electrical and mechanical properties by incorporating titanium oxide(TiO_(2))nanoparticles within PVC *** loading of nanoparticles and different nanoparticle surface states were *** surface states are unfunctionalised,functionalised using vinyl silane and functionalised using amino *** choice of a most suitable surface state was a critical factor that guarantees a good dispersion of nanoparticles and consequently enhances the compatibility between TiO_(2)and PVC *** process followed in the PVC/TiO_(2)nanocomposites preparation,loaded with different wt.%of TiO_(2)nanoparticles,was the solvent *** dielectric properties measured here were the relative permittivity(ɛr),dielectric loss(tanδ),breakdown strength(AC and DC under uniform field)and the internal partial discharges(PDs)within insulation *** measurements have been performed under room temperature and at frequency ranged from 20 to 1.0 ***,the mechanical properties of the samples like elongation,elasticity modulus and tensile strength were also *** silane showed better improvements in both electrical and mechanical performances compared to the amino silane,especially in cases of high weight fractions of TiO_(2).This is because of the improvement in the PVC-TiO_(2)interfacial region arise from the similarity of polarity and surface tension values of vinyl silane with that of PVC matrix and TiO_(2)nanoparticles.

关键词： dielectric insulation resistance

electromagnetic effects on the orbital motion of a charged spacecraft

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Research in Astronomy and Astrophysics 2014年第5期14卷 589-600页

作者： Yehia ahmed abdel-Aziz Khalil Ibrahim Khalil National Research Institute of Astronomy and Geophysics (NRIAG) Helwan Cairo 11721Egypt Department of Mathematics Hail University Hail 2440 Kingdom of Saudi Arabia

This paper deals with the effects of electromagnetic forces on the orbital motion of a spacecraft. The electrostatic charge which a spacecraft generates on its surface in the earth＇s magnetic field will be subject to a perturbative Lorentz force. A model incorporating all Lorentz forces as a function of orbital elements has been developed on the basis of magnetic and electric fields. This Lorentz force can be used to modify or perturb the spacecraft＇s orbits. Lagrange＇s planetary equations in the Gauss variational form are derived using the Lorentz force as a perturbation to a Keplerian orbit. Our approach incorporates orbital inclination and the true anomaly. The numer- ical results of Lagrange＇s planetary equations for some operational satellites show that the perturbation in the orbital elements of the spacecraft is a second order perturba- tion for a certain value of charge. The effect of the Lorentz force due to its magnetic component is three times that of the Lorentz force due to its electric component. In addition, the numerical results confirm that the strong effects are due to the Lorentz force in a polar orbit, which is consistent with realistic physical phenomena that occur in polar orbits. The results confirm that the magnitude of the Lorentz force depends on the amount of charge. This means that we can use artificial charging to create a force to control the attitude and orbital motion of a spacecraft.

关键词： space vehicles -- atmospheric effects -- celestial mechanics -- kine-matics and dynamics

Convolution-Transformer for Image Feature extraction

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Computer Modeling in engineering & Sciences 2024年第10期141卷 87-106页

作者： Lirong Yin Lei Wang Siyu Lu Ruiyang Wang Youshuai Yang Bo Yang Shan Liu ahmed AlSanad Salman A.AlQahtani Zhengtong Yin Xiaolu Li Xiaobing Chen Wenfeng Zheng Department of Geography and Anthropology Louisiana State UniversityBaton RougeLA70803USA School of Automation University of Electronic Science and Technology of ChinaChengdu610054China College of Computer and Information Sciences King Saud UniversityRiyadh11574Saudi Arabia College of Resources and environmental engineering Key Laboratory of Karst Georesources and Environment(Guizhou University)Ministry of EducationGuiyang550025China School of Geographical Sciences Southwest UniversityChongqing400715China School of electrical and Computer engineering Louisiana State UniversityBaton RougeLA70803USA

This study addresses the limitations of Transformer models in image feature extraction,particularly their lack of inductive bias for visual *** to Convolutional Neural Networks(CNNs),the Transformers are more sensitive to different hyperparameters of optimizers,which leads to a lack of stability and slow *** tackle these challenges,we propose the Convolution-based efficient Transformer Image Feature extraction Network(CeFormer)as an enhancement of the Transformer *** model incorporates e-Attention,depthwise separable convolution,and dilated convolution to introduce crucial inductive biases,such as translation invariance,locality,and scale invariance,into the Transformer ***,we implement a lightweight convolution module to process the input images,resulting in faster convergence and improved *** results in an efficient convolution combined Transformer image feature extraction *** results on the ImageNet1k Top-1 dataset demonstrate that the proposed network achieves better accuracy while maintaining high computational *** achieves up to 85.0%accuracy across various model sizes on image classification,outperforming various baseline *** integrated into the Mask Region-ConvolutionalNeuralNetwork(R-CNN)framework as a backbone network,CeFormer outperforms other models and achieves the highest mean Average Precision(mAP)*** research presents a significant advancement in Transformer-based image feature extraction,balancing performance and computational efficiency.

关键词： Transformer e-Attention depth convolution dilated convolution CeFormer

Synthesis and study the influence of yttrium doping on band structure,optical,non-linear optical and dielectric results for Ca_(12)Al_(14)O_(33) (C12A7) single crystals grown using traveling-solvent floating zone (TSFZ) method

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Chinese Physics B 2022年第1期31卷 626-630页

作者： A.abdel Moez ahmed I.Ali A.Tayel Solid State Physics Department Physical Research DivisionNational Research Centre(NRC)33 El Bohouth StreetDokkiGiza 12622Egypt Basic Science Department Faculty of Faculty of Technology and EducationHelwan UniversityKobry El-QopaCairo 11281Egypt

Ca_(12)Al_(14)O_(33)(C12A7)and Y_(0.02)Ca_(11.98)Al_(14)O_(33)(Y-C12A7)single crystals were grown by using the traveling-solvent floating zone(TSFZ)*** temperature was increased to avoid the bubbles and cracks which may be formed during the preparation of the ingot *** have started with the flux higher than the normal to avoid the bubbles and make good treatment for the solid-liquid *** structures of both Ca_(12)Al_(14)O_(33)(C12A7)and Y_(0.02)Ca_(11.98)Al_(14)O_(33)(Y-C12A7)were studied by using x-ray diffraction(XRD).Optical properties for C12A7 and Y-C12A7 single crystals have been studied in order to determine the optical parameters such as optical energy gap(eg),refractive index n,oscillating energy(eo),dispersion energy(ed),volume energy loss function(VeLF),and surface energy loss function(SeLF).Finally,a new result for these samples is that the third-order nonlinear optical susceptibility(χ(3))was *** results have been discussed with effect of Y-doping on the C12A7 single crystals for optical and industrial applications.

关键词： syntheses Ca_(12)Al_(14)O_(33)(C12A7)single crystals Y-doping optical parameters dielectric results nonlinear optical susceptibility

Processing of Landsat 8 Imagery and Ground Gamma-Ray Spectrometry for Geologic Mapping and Dose-Rate Assessment, Wadi Diit along the Red Sea Coast, egypt

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Open Journal of Geology 2016年第8期6卷 911-930页

作者： ahmed e. abdel gawad Atef M. Abu Donia Mahmoud elsaid Nuclear Materials Authority Cairo Egypt

Maximum Likelihood (MLH) supervised classification of atmospherically corrected Landsat 8 imagery was applied successfully for delineating main geologic units with a good accuracy (about 90%) according to reliable ground truth areas, which reflected the ability of remote sensing data in mapping poorly-accessed and remote regions such as playa (Sabkha) environs, subdued topography and sand dunes. Ground gamma-ray spectrometric survey was to delineate radioactive anomalies within Quaternary sediments at Wadi Diit. The mean absorbed dose rate (D), annual effective dose equivalent (AeDe) and external hazard index (Hex) were found to be within the average worldwide ranges. Therefore, Wadi Diit environment is said to be radiological hazard safe except at the black-sand lens whose absorbed dose rate of 100.77 nGy/h exceeds the world average. So, the inhabitants will receive a relatively high radioactive dose generated mainly by monazite and zircon minerals from black-sand lens.

关键词： Landsat 8 Imagery Image Processing Maximum Likelihood Classification environmental Monitoring Absorbed Dose Rate Hazard Index

Antifouling evaluation of extracts from Red Sea soft corals against primary biofilm and biofouling

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Asian Pacific Journal of Tropical Biomedicine 2017年第11期7卷 991-997页

作者： Yosry abdel Aziz Soliman ahmed Mohammed Brahim ahmed Hussein Moustafa Mohamed abdel Fattah Hamed Marine Chemistry Lab. Marine Environment DivisionNational Institute of Oceanography and FisheriesSuezEgypt Department of Chemistry Faculty of ScienceZagazig UniversityZagazigEgypt

Objectives: To evaluate antifouling property of extracts from Red Sea soft corals against primary biofilm and ***: Seven species of soft corals Sarcophyton glaucum(a), Sinularia compressa,Sinularia cruciata(a), Heteroxenia fuscescens(a), Sarcophyton glaucum(b), Heteroxenia fuscescens(b) and Sinularia cruciata(b) were chosen to test their extracts as antibacterial and antifouling agents in eastern Harbour of Alexandria, Mediterranean *** compounds of soft corals were extracted by using methanol and concentrated under vacuum. The residues of extracts were mixed in formulation of inert paint which consisted of rosin, chlorinated rubber and ferrous oxide against micro and macro fouling organisms. The formulated paints were then applied on PVC panels twice by brush,hanged in a steel frame and immersed in eastern Harbour of Alexandria Mediterranean Sea followed by visual inspection and photographic ***: After 185 days of immersion in seawater, the antifouling results agreed with the antibacterial results where extracts of Sinularia compressa and Heteroxenia fuscescens(b) gave the best activity against marine fouling tubeworms and barnacles. The inhibition activity was correlated with the major functional groups(hydroxyl, amino, carbonyl,aliphatic(fatty acids), C]C of alkene or aromatic rings and CeC l of aryl halides) of the ***: The strong antifouling activity makes them promising candidates for new antifouling additives. After the screening and application of natural organic compounds from soft corals, marine organisms show activity against micro and macro fouling organisms.

关键词： Antibacterial Antifouling Paints Seawater Marine Organisms