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Nuclear Science and Techniques 2022年第2期33卷 1-13页

作者： Khaled m.El-Azony Nader m.a.mohamed Dalal A.Aloraini Radioactive Isotopes and Generators Department Hot Labs.CenterEgyptian Atomic Energy AuthorityP.O.Box 13759CairoEgypt Reactors Department Egyptian Atomic Energy AuthorityP.O.Box 13759CairoEgypt Physics Department College of SciencePrincess Nourah Bint Abdulrahman UniversityRiyadhKingdom of Saudi Arabia

Production routes were recorded on available reactions for^(111)Ag production from nuclear reactors or cyclotrons using a natural palladium target based on^(110)Pd(n,γ)and^(110)pd(d,n)reactions,respectively.^(nat)Cd(γ,x)based on^(110)Cd(γ,p)has also been studied as a prospective reaction for the production of^(111)***,these nuclear reactions are difficult to utilize because,in some cases,they reduce the specific activity of^(111)*** is a consequence of the stable silver isotopes produced in high *** isotopes include^(107,109)Ag and,in other cases,the high impurity of silver radioisotopes,such as^(110)m,^(106)m,^(105)Ag,that are produced during parallel nuclear *** to a scarcity of data regarding the(γ,α)reaction,the gamma reaction on natural indium for^(111)Ag production based on the^(115)In(γ,α)reaction was *** ^(nat)In(γ,α)reaction satisfies the criteria as a possible reaction to produce^(111)Ag with a sufficient yield and purity as consequence of the high^(115)In(95.7%)abundance as an enriched form and a relatively soft background caused by the parallel nuclear reactions.

关键词： Silver-111 Nuclear data Natural cadmium Natural palladium Natural indium

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集约管理措施与小麦产量及品质

麦类作物学报 1991年第5期 36-37页

作者： m.a.mohamed ,常月帆

一些研究者曾报道:增施氮肥、窄行距、应用植物生长调节剂及杀菌剂可提高小麦产量.但是,论及这些因素及它们的相互作用对美国加州灌溉小麦生产的影响的报道却很少.为确定3种氮素水平(168,220和252kg/ha)在行距为10cm和17cm下应用生长调... 详细信息

一些研究者曾报道:增施氮肥、窄行距、应用植物生长调节剂及杀菌剂可提高小麦产量.但是,论及这些因素及它们的相互作用对美国加州灌溉小麦生产的影响的报道却很少.为确定3种氮素水平(168,220和252kg/ha)在行距为10cm和17cm下应用生长调节剂对半矮硬红春小麦Yecora Rojo的影响,在加州

关键词：小麦产量籽粒产量生长调节剂

Effects of P301L-TAU on post-translational modifications of microtubules in human iPSC-derived cortical neurons and TAU transgenic mice

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Neural Regeneration Research 2025年第8期20卷 2348-2360页

作者： mohamed Aghyad Al Kabbani Christoph Köhler Hans Zempel Institute of Human Genetics Faculty of Medicine and University Hospital CologneUniversity of CologneCologneGermany Center for molecular medicine Cologne(CmmC) University of CologneCologneGermany Center Anatomy Department ⅡMedical FacultyUniversity of CologneCologneGermany

TAU is a microtubule-associated protein that promotes microtubule assembly and stability in the *** is missorted and aggregated in an array of diseases known as *** are essential for neuronal function and regulated via a complex set of post-translational modifications,changes of which affect microtubule stability and dynamics,microtubule interaction with other proteins and cellular structures,and mediate recruitment of microtubule-severing *** impairment of microtubule dynamics causes neuronal dysfunction,we hypothesize cognitive impairment in human disease to be impacted by impairment of microtubule *** therefore aimed to study the effects of a disease-causing mutation of TAU(P301L)on the levels and localization of microtubule post-translational modifications indicative of microtubule stability and dynamics,to assess whether P301L-TAU causes stability-changing modifications to *** investigate TAU localization,phosphorylation,and effects on tubulin post-translational modifications,we expressed wild-type or P301L-TAU in human mAPT-KO induced pluripotent stem cell-derived neurons(i Neurons)and studied TAU in neurons in the hippocampus of mice transgenic for human P301L-TAU(p R5 mice).Human neurons expressing the longest TAU isoform(2N4R)with the P301L mutation showed increased TAU phosphorylation at the AT8,but not the p-Ser-262 epitope,and increased polyglutamylation and acetylation of microtubules compared with endogenous TAU-expressing neurons.P301L-TAU showed pronounced somatodendritic presence,but also successful axonal enrichment and a similar axodendritic distribution comparable to exogenously expressed 2N4R-wildtype-TAU.P301L-TAU-expressing hippocampal neurons in transgenic mice showed prominent missorting and tauopathy-typical AT8-phosphorylation of TAU and increased polyglutamylation,but reduced acetylation,of microtubules compared with non-transgenic *** sum,P301L-TAU results in changes in micr

关键词： human induced pluripotent stem cell microtubules P301L pR5 mice TAU tauopathy tubulin code

HIV感染病人mRS成像数据的因素分析:代谢产物有助于感染和痴呆的判定

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国际医学放射学杂志 2010年第2期 186-186页

作者： m.a.mohamed m.R.Lentz V.Lee E.F.Halpern N.Sacktor O.Selnes 范丽 morgan Department of Radiology and Radiological Science Johns Hopkins Medical Institutions1550 Orleans St492 CRB IIBaltimoreMD 21231USA

目的通过研究mRS各代谢产物在局部的变化及各产物与免疫学指标和认知机能障碍之间的相关性,制定人类HIV相关性痴呆的病理生理学模型。材料与方法研究符合HIPA

关键词： HIV 阳性代谢产物代谢物病人感染 mRS 因素分析因子分析

Dynamic Interaction Analysis of Coupled Axial-Torsional-Lateral mechanical Vibrations in Rotary Drilling Systems

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Structural Durability & Health monitoring 2025年第1期19卷 77-103页

作者： Sabrina meddah Sid Ahmed Tadjer Abdelhakim Idir Kong Fah Tee mohamed Zinelabidine Doghmane madjid Kidouche Applied Automation Laboratory Faculty of Hydrocarbons and ChemistryUniversity of BoumerdesBoumerdes35000Algeria Institute of Electrical and Electronic Engineering(IGEE) University of BoumerdesBoumerdes35000Algeria Laboratory of the Electrification of Industrial Enterprises University of BoumerdesBoumerdes35000Algeria Electrical Engineering Department Mohamed Boudiaf University of M’silaM’sila28000Algeria Department of Civil and Environmental Engineering King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Interdisciplinary Research Center for Construction and Building materials King Fahd University of Petroleum&Minerals(KFUPM)Dhahran31261Saudi Arabia

maintaining the integrity and longevity of structures is essential in many industries,such as aerospace,nuclear,and *** achieve the cost-effectiveness of large-scale systems in petroleum drilling,a strong emphasis on structural durability and monitoring is *** study focuses on the mechanical vibrations that occur in rotary drilling systems,which have a substantial impact on the structural integrity of drilling *** study speciﬁcally investigates axial,torsional,and lateral vibrations,which might lead to negative consequences such as bit-bounce,chaotic whirling,and high-frequency *** events not only hinder the efﬁciency of drilling but also lead to exhaustion and harm to the system’s components since they are difﬁcult to be detected and controlled in real *** study investigates the dynamic interactions of these vibrations,speciﬁcally in their high-frequency modes,usingﬁeld data obtained from measurement while ***ﬁndings have demonstrated the effect of strong coupling between the high-frequency modes of these vibrations on drilling sys-tem *** obtained results highlight the importance of considering the interconnected impacts of these vibrations when designing and implementing robust control ***,integrating these compo-nents can increase the durability of drill bits and drill strings,as well as improve the ability to monitor and detect ***,by exploiting theseﬁndings,the assessment of structural resilience in rotary drilling systems can be ***,the study demonstrates the capacity of structural health monitoring to improve the quality,dependability,and efﬁciency of rotary drilling systems in the petroleum industry.

关键词： Rotary drilling systems mechanical vibrations structural durability dynamic interaction analysis ﬁeld data analysis

An unstructured mesh method for numerical simulation of violent sloshing flows

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Journal of Hydrodynamics 2020年第2期32卷 259-266页

作者： Changhong Hu mohamed m.Kamra Research Institute for Applied mechanics Kyushu UniversityFukuokaJapan

An unstructured mesh Reynolds-averaged Navier-Stokes(RANS)solver has been developed for numerical simulation of violent sloshing flows inside a tank with complicated inner *** numerical solver employs the unstructured multi-dimensional tangent hyperbolic interface capturing method(UmTHINC)for free-surface capturing combined with various turbulence *** sloshing motion is numerically modeled using the body-force method which introduces a source term into the momentum equation corresponding to the tank motion *** simulations of the tank sloshing problems are performed for different test cases with various oscillation *** performance of the interface capturing method has been discussed and the effect of turbulence model choice on loading predictions is highlighted by studying several RANS models and analyzing its effect on fluid motion and impact *** simulations of the sloshing inside the tank with a vertical baffle has also been conducted and a discussion is provided on different numerical treatment of the baffle.

关键词： Unstructured mesh RNAS solver UmTHINC scheme violent sloshing flow

microstructure and mechanical properties of hot extruded 6016 aluminum alloy/graphite composites

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Journal of materials Science & Technology 2018年第9期34卷 1580-1591页

作者： mohamed m.El-Sayed Seleman mohamed m.Z.Ahmed Sabbah Ataya Department of metallurgical and materials Engineering Faculty of Petroleum and Mining Engineering Suez University 43518 Suez Egypt Suez and Sinai metallurgical and materials Research Center of Scientific Excellence (SSmmR-CSE) 43518 Suez Egypt The British University in Egypt Mechanical Engineering Deportment El-Sherouk City 11837 Cairo Egypt Department of mechanical Engineering College of Engineering AI Imam Mohammad Ibn Saud Islamic University Riyadh 11432 saudi Arabia

The incorporation of graphite particles into AA6016 aluminum alloy matrix to fabricate metal/ceramic composites is still a great challenge and various parameters should be considered. In this study, dense AA6016 aluminum alloy/（0-20 wt%） graphite composites have successfully been fabricated by powder metallurgy process. At first, the mixed aluminum and graphite powders were cold compacted at 200 mPa and then sintered at 500 ℃ for 1 h followed by hot extrusion at 450 ℃. The influence of ceramic phases（free graphite and in-situ formed carbides） on microstructure, physical and mechanical properties of the produced composites were finally investigated. The results show that the fabricated composites have a relative density of over 98%. SEm observations indicate that the graphite has a good dispersion in the alloy matrix even at high graphite content. Hardness of all the produced composites was higher than that of aluminum alloy matrix. No cracks were observed at strain less than 23% for all hot extruded *** strength, reduction in height, ultimate tensile stress, fracture stress, yield stress, and fracture strain of all Al/graphite composites were determined by high precision second order equations. Both compressive and ultimate tensile strengths have been correlated to microstructure constituents with focusing on the in-situ formed ceramic phases, silicon carbide（SiC） and aluminum carbide（Al4 C3）. The ductile fracture mode of the produced composites became less dominant with increasing free graphite content and in-situ formed carbides. Wear resistance of Al/graphite composites was increased with increasing graphite content. Aluminum/20 wt% graphite composite exhibited superior wear resistance over that of AA6016 aluminum alloy.

关键词： AA6016/graphite composites Hot extrusion In-situ carbides mechanical properties Wear resistance Fracture behavior

Exploration of structural,optical,and photoluminescent properties of (1-x)NiCo_(2)O_(4)/xPbS nanocomposites for optoelectronic applications

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Chinese Physics B 2022年第6期31卷 663-670页

作者： Zein K Heiba mohamed Bakr mohamed Noura m Farag Ali Badawi Physics Department Faculty of ScienceAin Shams UniversityCairoEgypt Physics Department Faculty of ScienceTaibah UniversityAl-Madina al MunawarahSaudi Arabia Department of Physics College of ScienceTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Department of Physics University College of TurabahTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia

The(1-x)NiCo_(2)O_(4)/x PbS(0≤x≤0.2)nanocomposite samples are synthesized using the hydrothermal and thermolysis *** different phases developed in the obtained nanocomposite samples are accurately determined using the x-ray diffraction technique equipped with a *** percentage of the formed phases(NiCo_(2)O_(4)(NCO),PbS,PbSO_(4)),structural and microstructure parameters are determined using Rietveld quantitative phase *** transmission electron microscope(TEm)images and Rietveld analysis reveal almost isotropic particle size in the nano range with a very narrow size *** obtained phase percentage of PbS and PbSO4are smaller than nominated values(x)suggesting dissolving of some Pb and S ions into NCO which is then confirmed by the analysis of Fourier-transform infrared(FTIR)spectra of nanocomposite *** absorption spectra are modified upon doping NCO with *** optical band gaps of the nanocomposites increase as the amount of PbS *** effect of alloying on extinction coefficient,refractive index,dielectric constant,optical conductivity,the intensity,and emitted color from the photoluminescence of the nanocomposite samples are also *** refractive index value of NCO and NCO-PbS nanocomposite samples exhibit normal *** photoluminescent measurements reveal that the NCO-PbS nanocomposites can emit a violet *** improvement in the values of the nonlinear optical(NLO)parameters of pristine NCO at high frequencies or the nanocomposite samples at low frequencies,are made them used in NLO photonic devices.

关键词： Co_(2)O_(4)and PbS nanocomposite FTIR optical photoluminescence

Linearly and Quadratically Separable Classifiers Using Adaptive Approach

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Journal of Computer Science & Technology 2011年第5期26卷 908-918页

作者： mohamed Abdel-Kawy mohamed Ali Soliman Rasha m.Abo-Bakr Department of Computer and Systems Engineering Faculty of EngineeringZagazig UniversityZagazigEgypt Departement of mathematics Faculty of ScienceZagazig UniversityZagazigEgypt

This paper presents a fast adaptive iterative algorithm to solve linearly separable classification problems in R *** each iteration,a subset of the sampling data （n-points,where n is the number of features） is adaptively chosen and a hyperplane is constructed such that it separates the chosen n-points at a margin and best classifies the remaining *** classification problem is formulated and the details of the algorithm are ***,the algorithm is extended to solving quadratically separable classification *** basic idea is based on mapping the physical space to another larger one where the problem becomes linearly *** illustrations show that few iteration steps are sufficient for convergence when classes are linearly *** nonlinearly separable data,given a specified maximum number of iteration steps,the algorithm returns the best hyperplane that minimizes the number of misclassified points occurring through these *** with other machine learning algorithms on practical and benchmark datasets are also presented,showing the performance of the proposed algorithm.

关键词： linear classification quadratic classification iterative approach adaptive technique

Processing of Ceramic Based Nanocomposite Usingα-Al_2O_3 Powder and FeCl_2 Solution as Starting materials

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Journal of materials Science & Technology 2007年第6期23卷 837-842页

作者： mohamed m.EL-Sayed Seleman Department of materials and metallurgical Engineering Faculty of Petroleum and Mining EngineeringPost Code 43721SuezEgypt

Alumina-iron nanocomposite powders were prepared by a two-step process. In the first step, α-Al2O3-FeCl2 powder mixture was formed by mixing α-Al2O3 powders with FeCl2 solution followed by drying. In the second step, the FeCl2 in the dry power mixture was selectively reduced to iron particles. A reduction temperature of 750℃ for 15 min in dry H2 was chosen based on the thermodynamic calculations. The concentration of iron in FeCl2 solution was calculated to be 20 vol. pct in the final composite. Two techniques were used to produce composite bulk materials. The Al2O3 nanocomposite powders were divided to two batches. The first batch of the produced mixture was hot pressed at 1400℃ and 27 mPa for 30 min in a graphite die. To study the effect of oxygen on the Al2O3/Fe interface bonding and mechanical properties of the composite, the second batch was heat treated in air at 700℃ for 20 min to partially oxidize the iron particles before hot pressing. Characterization of the composites was undertaken by conventional density measurements, X-ray diffractometry （XRD）, scanning electron microscopy （SEm）, transmission electron microscopy （TEm） and electron probe micro analysis （EPmA）. The suggested processing route （mixing, reduction and hot pressing） produces ceramic-metal nanocomposite much tougher than the pure Al2O3. The fracture strength of the produced Al2O3/Fe nanocomposite is nearly twice that of the pure Al2O3. The presence of spinel phase, FeAl204, as thick layer around the Fe particles in the Al2O3 matrix has a detrimental effect on interfacial bonding between Fe and AI203 and the fracture properties of the composite.

关键词： Ferrous chloride Reduction Alumina-iron nanocomposite Spinel phase