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Effect of concrete buildings on the environmental neutron flux by using the reaction ^(197)Au (n,γ) ^(198)Au and extremely low level gamma ray spectroscopy

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Nuclear Science and Techniques 2004年第6期15卷 368-374页

作者： k. kOMURA N.k. ahmed A.H. EL-kAMEL A.M.M. YOUSEF Low Level Radioactivity Laboratory Kanazawa University Wake Tatsunokuchi Ishikawa 923-1224 JapanPhysics Department Faculty of Science South Valley University Kena EgyptPhysics Department Faculty of Science Assiut University Assiut EgyptPhysics Department Faculty of Science South Valley University Kena Egypt

The activation of gold by environmental neutrons through the reaction 197Au (n,γ) 198Au was used to study the effect of concrete buildings on the neutron flux, and to estimate the thermal neutron flux inside and outside these buildings. The results showed that three ceilings of thickness 34 g/cm2 decrease the fast neutrons to 26% from its original value. However, the same reinforced concrete decreases the slow neturon flux to only 62% of its original value. The thermal neutron flux at 283 m from the center of Training Reactor of kinki University, was twice higher than the environmental neutron background.

关键词：金活性混凝土环境中子宇宙射线

Relative Explosive Strength of Some Explosive Mixtures Containing Urea and/or Peroxides

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火炸药学报 2016年第5期39卷 22-27,34页

作者： ahmed k.HUSSEIN Svatopluk ZEMAN Muhamed SUCESkA Marcela JUNGOVA Institute of Energetic Materials Faculty of Chemical Technology University of Pardubice Czech Republic Brodarski Institute-Marine Research and Special Technologies ZagrebCroatia

Several mixtures,based on urea derivatives and some inorganic oxidants,including also alumina,were studied by means of ballistic mortar techniques with TNT as the reference *** detonation pressure(P),detonation velocity(D),detonation energy(Q),and volume of gaseous product at standard temperature and pressure(STP),V,were calculated using EXPLO5V6.3 thermochemical *** performance of the mixtures studied was discussed in relation to their thermal reactivity,determined by means of differential thermal analysis(DTA).It is shown that the presence of hydrogen peroxide in the form of its complex with urea(*** UHP)has a positive influence on the explosive strength of the corresponding mixtures which is linked to the hydroxy-radical formation in the mixtures during their initiation *** radicals might initiate(at least partially)powdered aluminum into oxidation in the CJ plane of the detonation *** containing UHP and magnesium are dangerous because of potential auto-ignition.

关键词： ballistic mortar TNT DTA peroxides perchlorates nitrates urea

Variation of environmental neutron flux with altitude and depth of both water and soil

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Nuclear Science and Techniques 2004年第4期15卷 248-256页

作者： k.kOMURA N.k.ahmed A.H.EL-kAMEL A.M.M.YOUSEF Low Level Radioactivity Laboratory Kanazawa UniversityWake TatsunokuchiIshikawa 923-1224JapanPlrysics DepartmentFaculty of Science.South Valley UniversityKenaEgyptPhysics DepartmentFaculty of ScienceAssiut UniversityAssiutEgyptPhysics DepartmentFaculty of Science.South Valley UniversityKenaEgypt

Applying the extreme low-level γ-ray spectroscopic analysis the environmental neutron flux is measured using different moderator construction and environment through the reaction 197Au (n, γ) 198Au. The contribution of thermal and resonance neutrons is separated using the cadmium difference technique, while fast neutrons are measured by the paraffin moderator. The results of altitude dependence of the neutron flux are discussed. The thermal neutron flux near the surface of sea water is less than its value at 100 cm over ground near sea water, while the value over the surfaces of fresh water is higher than that near the surface of sea water. Also the thermal neutron flux at 5 cm soil depth increases, then decreases to its original value at 10 cm depth and still constant until 25 cm, then decreases rapidly to reach 27% of its original value at 60 cm depth. The soil compositions, corresponding neutron temperatures and effective absorption cross sections of earth are the most effective factors on the equilibrium region of thermal neutrons in the ground.

关键词：环境中子流金活化作用 γ射线光谱学环境放射学水土壤

Effect of lengthening along the anatomical axis of the femur and its clinical impact

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World Journal of Orthopedics 2017年第5期8卷 431-435页

作者： khaled M Emara ahmed Nageeb Mahmoud ahmed k Emara Mariam k Emara Limb Reconstruction and Deformity Correction Unit Orthopaedic Surgery Department Ain Shams University Hospitals

AIM To review and study the effect of lengthening along the anatomical axis of long bones and its relation to the mechanical axis *** We try in this review to calculate and discuss the exact clinical impact of lengthening along the anatomical axis of the femur on affecting the limb alignment. Also we used a trigonometric formula to predict the change of the femoral distal anatomical mechanical angle(AMA) after lengthening along the anatomical axis. RESULTS Lengthening along the anatomical axis of the femur by 10% of its original length results in reduction in the distal femoral AMA by 0.57 degrees. There is no objective experimental scientific data to prove that the Mechanical axis is passing via the center of the hip to the center of the knee. There is wide variation in normal anatomical axis for different populations. In deformity correction, surgeons try to reproduce the normal usual bone shape to regain normal function, which is mainly anatomical axis. CONCLUSION Lengthening of the femur along its anatomical axis results in mild reduction of the distal femoral AMA. This may partially compensate for the expected mechanical axis lateralisation and hence justify its minimal clinical impact.

关键词： Bone lengthening Deformity Femoral lengthening External fixation Intramedullary nail Axis deviation

APPLICABILITY OF HAMILTON-JACOBI METHOD TO NONLINEAR NONHOLONOMIC SYSTEMS

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Applied Mathematics and Mechanics(English Edition) 1988年第10期9卷 937-952页

作者： Q.k.Ghori,Naseer ahmed Mathematics Department Quaid-i-Azam University Islamabad Pakistan Mathematics Department Quaid-i-Azam University Islamabad Pakistan

This paper uses Poincare formalism to obtain a generalization of the Hamilton-Jacobi method of integrating dynamical systems moving with nonlinear nonholonomic constraints. Necessary and sufficient conditions are investigated for the applicability of this method to such systems. The method is illustrated by considering some concrete examples of nonholonomic systems.

关键词： show In APPLICABILITY OF HAMILTON-JACOBI METHOD TO NONLINEAR NONHOLONOMIC SYSTEMS 一主丫二

Antihyperglycemic and antioxidant effects of Solanum xanthocarpum leaves(field grown & in vitro raised) extracts on alloxan induced diabetic rats

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Asian Pacific Journal of Tropical Medicine 2011年第10期4卷 778-785页

作者： k Poongothai P Ponmurugan k Syed Zameer ahmed B Senthil kumar SA Sheriff Research and Development Centre Bharathiar UniversityCoimbatore-646041Tamil NaduIndia Department of Biotechnology K.S.Rangasamy College of TechnologyK.S.R.KalvinagarThiruchengode-637215Tamil NaduIndia Department of Biotechnology K.S.Ranga.samy College of TechnologyK.S.R.KalvinagarThiruchengode-637215Tamil NaduIndia Department of Biochemistry C.Abdul Hakeem CollegeMelvisharam-632509Tamil NaduIndia Department of Zoology Thiruvalluvar UniversitySerkaduVelloreTamil NaduIndia Department of Biochemistry College of Applied Medical SciencesShaqra UniversityShaqra-11961.Kingdom of Saudi Arabia

Objective:To investigate antidiabetic efficacy of the extract of field grown and in vitro raised leaves of Solanum xanthocarpum(***) against alloxan induced diabetic rats. Methods:The antidiabetic activity of the crude methanol extracts of the field grown and in vitro raised leaves of *** at different concentrations(100-200 mg/kg bw) was tested against alloxan induced diabetic *** antidiabetic efficacy was validated through various biochemical parameters and the antioxidant effect was also *** phytochemical analyses of field grown *** and in vitro rasied *** leaves were done by estimating their chlorophyll,carotenoids,total sugar,protein,amino acid and minerals contents. Results:The results revealed that the methanol extracts of both the leaves(field grown and in vitro raised) of *** was efficient anti hyperglycemic agents at a concentration of 200 mg/kg bw and posses potent antioxidant ***,the extracts of in vitro rasied *** raised leaves exhibit higher efficacy than the field grown leaves in all tested *** composition and mineral analysis of *** revealed higher concentration of contents in in vitro rasied *** than field grown ***. Conclusions:From the results it can be concluded that the leaves extracts of *** can be a potential candidate in treating the hyperglycemic conditions and suits to be an agent to reduce oxidative stress.

关键词： Solanum Xanthocarpum Alloxan Field grown In vitro Oxidative stress Antioxidant Hyperglycemia Hypolipidemic

Impact of composition ratio on the structure and optical properties of(1-x)MnFe_(2)O_4/(x)ZnMn_(2)O_4 nanocomposite

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Chinese Physics B 2022年第7期31卷 481-489页

作者： Zein k.Heiba Mohamed Bakr Mohamed Ali A.Alkathiri Sameh I.ahmed A A Alhazime Department of Physics Faculty of ScienceAin shams UniversityCairo 11566Egypt Physics Department Faculty of ScienceTaibah UniversityAl-Madina al MunawarahSaudi Arabia Depatment of Physics College of ScienceTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia

(1-x)MnFe_(2)O_(4)(MFO)/xZnMn_(2)O_(4)(ZMO)(x=0,0.2,0.5,0.8,and 1.0)nanocomposite samples were prepared using co-precipitation *** phase percentage,cell parameters,and crystallite size of MFO and ZMO phases in each nanocomposite sample were calculated using Rietveld refinement *** x-ray diffraction(XRD)analysis and Fourier-transform infrared spectroscopy techniques established the variation in the lattice parameters of each phase are due to permutation of all cations among the octahedral and tetrahedral sites of MFO and *** different oxidation states of different ions in all samples were determined using x-ray photoelectron spectroscopy(XPS)*** variation in absorbance of the nanocomposite samples with composition parameter(x)is dependent on the wavelength *** optical bandgap of the nanocomposite samples is decreased as the content of ZMO phase *** effect of alloying on the refractive index,extinction coefficient,dielectric constant,optical conductivity,and the nonlinear optical behaviors of all samples were studied in *** nanocomposite sample x=0.5 disclosed upgraded optical parameters with the highest refractive index,optical conductivity,and PL intensity,which nominate it to be functional in various application fields.

关键词： MFO and ZMO composite XPS structure optical

Protective Coatings Containing ZnMOF-BTA Metal–Organic Framework for Active Protection of AA2024-T3

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Acta Metallurgica Sinica(English Letters) 2023年第11期36卷 1893-1908页

作者： Izuchukwu k.Nwokolo Hongwei Shi Paul CUzoma Sharjeel ahmed Jiwen Li Fuchun Liu CAS key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei230026China School of Materials Science and Engineering Shenyang University of TechnologyShenyang110870China ZJU-UIUC Institute International CampusZhejiang UniversityHaining314400China Institute of Corrosion Science and Technology Guangzhou510530China

ZnMOF-BTA,a new metal–organic framework with excellent anti-corrosion properties was prepared and *** and immersion tests in 3.5 wt%NaCl were performed on AA2024-T3 alloy to assess the corrosion inhibition ability of *** showed an inhibition efficiency of more than 90%,indicating excellent corrosion inhibition of ZnMOF-BTA on AA 2024-T3 in ***,ZnMOF-BTA particles were incorporated into polyurethane coatings to create corrosion-resistant *** tests and neutral salt spray analysis were used to assess the corrosion protection ability of ZnMOF-BTA-laden polyurethane *** results of electrochemical impedance spectra clearly showed the outstanding corrosion resistance and durability of ZnMOF-BTA coatings after 1440 h of immersion with a high pore resistance(Rpo)of 1.76×10^(10)Ωcm^(2).In addition,during the cross-cut adhesion test,the coating did not detach from the substrate,and after the impact test,there was scarcely any indication of a fracture,which further supports the notion that the coating has strong adhesion to the substrate.

关键词： Aluminum alloy Benzotriazole Corrosion inhibition Electrochemical impedance spectroscopy(EIS) Metal-organic framework Organic coatings

Insights into the adsorption performance and mechanism of Cr(Ⅵ)onto porous nanocomposite prepared from gossans and modified coal interface:Steric,energetic,and thermodynamic parameters interpretations

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Chinese Journal of Chemical Engineering 2023年第9期61卷 118-128页

作者： Mohamed Mobarak Saleh Qaysi Mohamed Saad ahmed Yasser F.Salama ahmed Mohamed Abbass Mohamed Abd Elrahman Hamdy AAbdel-Gawwad Moaaz k.Seliem Physics Department Faculty of ScienceBeni-Suef UniversityEgypt Geology and Geophysics Department College of ScienceKing Saud University11451 RiyadhSaudi Arabia Geology Department Faculty of ScienceBeni-Suef UniversityEgypt Department of Building Materials and Construction ChemistryInstitute of Civil EngineeringTechnische Universitat BerlinBerlinGermany Structural Engineering Department Faculty of EngineeringMansoura UniversityMansouraEgypt Raw Building Materials and Processing Technology Research Institute Housing and Building National Research Center(HBRC)CairoEgypt Faculty of Earth Science Beni–Suef UniversityEgypt

Herein,iron oxide/hydroxides deposits(gossans)were utilized,for the first time,in the fabrication of magnetite nanoparticles(MNPs)to load modified coal(MC).The as-synthesized MNPs@MC composite was characterized via different techniques and utilized for the Cr(Ⅵ)*** studies supported by theoretical treatment were applied to offer a new overview of the Cr(Ⅵ)adsorption geometry and mechanism at 25-45℃.Experimental results suggested that the Cr(Ⅵ)uptake was mainly governed by adsorption-reduction coupled *** Langmuir model fitted well the Cr(Ⅵ)adsorption data with maximum adsorption capacities extended from 115.24 to 129.63 mg·g^(-1).Theoretical calculations indicated that Cr(Ⅵ)ions were adsorbed on the MNPs@MC following the theory of the advanced monolayer statistical *** number of ions removed per site ranged from 1.88 to1.23 suggesting the involvement of vertical geometry and multi-ionic mechanism at all *** increment of the active sites density and the adsorption capacity at saturation with improving temperature reflected an endothermic ***,the Cr(Ⅵ)adsorption was controlled by physical forces as the adsorption energies were less than 40 kJ·mol^(-1).The calculated free enthalpy,*** internal energy explained the spontaneous nature and the viability of Cr(Ⅵ)adsorption on the MNPs@MC *** results offer a new approach in utilizing the iron-rich deposits as gossans in the preparation of magnetic and low-cost adsorbents for wastewater remediation.

关键词： Coal Magnetic nanoparticles Cr(Ⅵ)adsorption Statistical models Thermodynamic parameters