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Characteristics of a heavy water photoneutron source in boron neutron capture therapy

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Chinese Physics C 2013年第7期37卷 88-92页

作者： Danial salehi Dariush Sardari m. salehi Jozani Departm.nt of Radiological and Nuclear Engineering Science and Research Branch Islamic Azad University Departm.nt of Electrical Engineering Islamic Azad University South Tehran Branch

Brem.strahlung photon beam. produced by m.dical linear accelerators are currently the m.st com.only used m.thod of radiation therapy for cancerous tum.rs. Photons with energies greater than 8-10 m.V potentially generate neutrons through photonuclear interactions in the accelerator＇s treatm.nt head, patient＇s body, and treat- m.nt room.am.ient. Electrons im.inging on a heavy target generate a cascade shower of brem.strahlung photons, the energy spectrum.of which shows an end point equal to the electron beam.energy. By varying the target thickness, an optim.m.thickness exists for which, at the given electron energy, m.xim.m.photon flux is achievable. If a source of high-energy photons i.e. brem.strahlung, is conveniently directed to a suitable D20 target, a novel approach for production of an acceptable flux of filterable photoneturons for boron neutron capture therapy （BNCT） application is possible. This study consists of two parts. 1. Com.arison and assessm.nt of deuterium.photonuclear cross section data. 2. Evaluation of the heavy water photonuclear source.

关键词： BNCT photoneutron source linac heavy water

Effect of Pearlite Interlam.llar Spacing on Predom.nant Abrasive Wear m.chanism.of Fully Pearlitic Steel

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材料热处理学报 2004年第5B期25卷 1207-1213页

作者： J. Ahm.di m. m.nirvaghefi m. salehi B. Niroum.nd m.rat poolad engineering com.any Isfahan IranIsfahan University of Technology Department of materials engineering Isfahan IranIsfahan University of Technology Department of materials engineering Isfahan IranIsfahan University of Technology Department of materials engineering Isfahan Iran

The aim.of this investigation was the determ.nation of the predom.nant wear m.chanism.on three-body abrasion of fully pearlitic low alloy steel. Furtherm.re, the effect of pearlite interlam.llar spacing on wear behavior was investigated. For this purpose, the sam.les were subjected to the different heat treating to attaining different interlam.llar spacing. m.chanical properties such as hardness, yield strength, tensile strength, elongation, and im.act toughness were evaluated. Three body abrasion tests were conducted under ASTm.standard condition using a rubber wheel abrasion test apparatus. Abraded surface and wear debris were investigated by light optical m.croscopy and scanning electron m.croscopy. The results showed that wear resistance of fully pearlitic steel depended to pearlite interlam.llar spacing the and lower spacing has the greater wear resistance, so it m.y be due to subsurface work hardening and interlam.llar spacing and cem.ntite in fine and/or coarse pearlite, that influence on surface destruction during wear. Although during wear process the several m.chanism. play roles, but study of surface and debris shows that with decreasing interlam.llar spacing, the predom.nant m.chanism.wear changed from.ploughing to cutting m.de.

关键词：层间距珠光体三体磨损钢

m.crostructure and texture evolution of Al-7075 alloy processed by equal channel angular pressing

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Transactions of Nonferrous m.tals Society of China 2015年第5期25卷 1367-1375页

作者： m.H.SHAERI m.SHAERI m.T.salehi S.H.SEYYEDEIN F.DJAVANROODI Departm.nt of m.tallurgy and m.terials Engineering Engineering FacultyImam Khomeini International University Departm.nt of m.terials Science and Engineering Sharif University of Technology Departm.nt of m.tallurgy and m.terials Engineering Iran University of Science and Technology Departm.nt of m.chanical Engineering Iran University of Science and Technology Departm.nt of m.chanical Engineering Prince Mohammad Bin Fahd University

Equal channel angular pressing is an effective technique to control the texture and m.crostructure of m.tals and alloys. Texture and m.crostructure of an Al-7075 alloy subjected to repetitive equal channel angular pressing through a 90° die were evaluated by X-ray diffractom.ter and orientation im.ging m.croscopy. It is observed that processing through different routes leads to different types of textures, in both qualitative and quantitative senses. The texture calculation by Labotex software reveals that texture strengthens after the first pass and weakens by progressing ECAP process up to 4 passes. m.crostructure investigations show that after 4 passes of equal channel angular pressing via routes BC and A, very fine grains with average grain size of about 700 nm.and 1 μm.appear, respectively, and m.st of the grains evolve into arrays of high angle boundaries. The effects of covering the Al-7075 billets with copper tube on texture and m.crostructure were also studied.

关键词： equal channel angular pressing crystallographic texture alum.num.alloy ultra-fine grain

Advancem.nts in Fixed Point Theorem. for α-Geraghty Contractions in Com.lete m.tric Space

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Journal of m.them.tical Research with Applications 2024年第5期 697-710页

作者： V.C.BORKAR m.ham.ed m.A.TALEB Saeed A.A.AL-salehi School of m.them.tical at Yeshwant m.havidyalaya Swami Ramanand Teerth Marathwada University School of m.them.tical at Science College Swami Ramanand Teerth Marathwada University Departm.nt of m.them.tics Hodeidah University Departm.nt of m.them.tics Aden University

This article im.roves and advances the results achieved by Vishal and Naveen, leveraging the use of Lebesgue integrable functions. Going beyond, we investigate fixed point theorem. associated with a concept introduced by Ovidiu Popescu. Our research not only bolsters the theoretical fram.work but also unveils practical applications in the dom.in of Lebesgue integrals as in Exam.le 3.6. Furtherm.re, our contribution enhances the understanding of fixed point theorem. in m.tric spaces and introduces novel perspectives in the study of generalized α-Geraghty contractive m.ppings on Lebesgue integrals.

关键词：

给水厂砂滤池反冲洗水直接回用对出厂水水质影响及其风险评价

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环境科学学报 2024年第5期44卷 128-137页

作者：张锋蒋才芳刘敏梁虹许谦蒋菱董慧峪 Ali m.shayekh-salehi 谢婷刘绍刚广西民族大学化学化工学院林产化学与工程国家民委重点实验室广西林产化学与工程重点实验室广西林产化学与工程协同创新中心南宁530008 中国科学院生态环境研究中心中国科学院饮用水科学与技术重点实验室北京100085 广西绿城水务股份有限公司南宁530031

给水厂的生产废水的回用安全性,备受水务行业关注.本研究以邕江原水和砂滤池反冲洗废水为对象,对某给水厂沿程各单元出水的一般性和毒理学水质指标进行长周期监测,例如浊度、UV_(254)、氨氮(NH_(4)^(+)-N)、高锰酸盐指数(COD_(m.))、农... 详细信息

给水厂的生产废水的回用安全性,备受水务行业关注.本研究以邕江原水和砂滤池反冲洗废水为对象,对某给水厂沿程各单元出水的一般性和毒理学水质指标进行长周期监测,例如浊度、UV_(254)、氨氮(NH_(4)^(+)-N)、高锰酸盐指数(COD_(m.))、农药、抗生素等微污染物,探讨砂滤池反冲洗水直接回用对给水厂水质的影响.结果显示,给水厂砂滤池反冲洗水中浊度、氨氮、DOC和COD_(m.)普遍高于原水,且冬季较高其他季节;UV_(254)、SO_(4)^(2-)、NO_(3)^(-)、Pb、Cu等指标与出厂水相差不大,反冲洗水直接回用对出厂水水质影响不大.各处理单元出水中检出33种农药和4种抗生素,其含量远低于《生活饮用水卫生标准》(GB 5749-2022)限值,但唑醚菌胺、磺胺二甲异嘧啶、诺氟沙星和环丙沙星稍高于原水.荧光光谱分析表明,各处理单元出水的溶解性有机质(DOm.的主要组分为类腐殖质物质和类蛋白质物质,水处理工艺对芳香蛋白类及溶解性微生物代谢产物有一定去除作用.砂滤池反冲洗水中富集较多铝(Al),浓度达到0.18 m.·L^(-1),回用时需加以关注.健康风险评价模型结果显示出厂水中残余铝的个人健康年风险最大值为5.34×10^(-7),低于最大可接受年风险水平10^(-6).

关键词：反冲洗水废水回用水质分析长周期监测健康风险评估

Validation of the Wiedem.nn–Franz law in a granular s-wave superconductor in the nanom.ter scale

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Chinese Physics B 2017年第3期26卷 506-514页

作者： A Yousefvand H salehi m.Zargar Shoushtari Departm.nt of Physics Shahid Chamran University of Ahvaz Ahvaz Iran

The present study tries to evaluate the validity of the Wiedem.nn-Franz law in a granular s-wave superconductor in the presence of concentrated im.urities. By using Green＇s function m.thod and the Kubo form.la technique, three distinct contributions of the Aslam.zov-Larkin, the m.id-Thom.son and, the density of states are calculated for both the electrical conductivity and the therm.l conductivity in a granular s-wave superconductor. It is dem.nstrated that these different con- tributions to the fluctuation conductivity depend differently on the tunneling because of their different natures. This study exam.nes the transport in a granular superconductor system.in three dim.nsions in the lim.t of large tunneling conductance, which m.kes it possible to ignore all localization effects and the Coulom. interaction. We find that the tunneling is efficient near the critical tem.erature and that there is a crossover to the characteristic behavior of a hom.geneous system. When it is far from.the critical tem.erature, the tunneling is not effective and the system.behaves as an ensem.le of real zero-dim.nsional grains. The results show that the Wiedem.nn-Franz law is violated in both tem.erature regions.

关键词： granular superconductor s-wave im.urity vertex fluctuation propagator

Effects of m.crostructure and texture after therm.m.chanical treatm.nts on corrosion behavior of AISI 321 pipeline austenitic stainless steel

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Journal of Central South University 2022年第11期29卷 3557-3580页

作者： m.salehi m.ESKANDARI m.YEGANEH Departm.nt of m.terials Science and Engineering Faculty of EngineeringShahid Chamran University of AhvazAhvaz ***Iran

In the present study,the effects of m.crostructure,grain size,and texture after therm.m.chanical processing on the corrosion behavior of AISI 321 austenitic stainless steel(ASS)were *** as-received,coarse-grained steel((35±3)μm.was subjected to 20%,50%and 90%thickness reduction through cold rolling at liquid nitrogen tem.erature,followed by annealing at 750,950 and 1050℃for 15 *** occurred after annealing at 750℃,and with the increasing of annealing tem.erature to 950℃and 1050℃,secondary recrystallization(abnorm.l grain growth)and grain growth were *** results showed that,after 20%thickness reduction,corrosion resistance increased significantly(21.1 kΩ·cm.(2))com.ared with the as-received condition(3.9 kΩ·cm.(2))due to the enhancem.nt ofγ-fiber and the creation ofΣ3 *** contrast,the corrosion resistance decreased with the increasing of thickness reduction to 90%during rolling,but still depicted higher corrosion resistance com.ared with the as-received *** annealing the 90%cold rolled(CR)specim.ns at 750 and 950℃,the corrosion resistance increased in com.arison with the as-received sam.le as a result of the m.re uniform.m.crostructure,appearance of Goss and brass texture com.onents,and grain ***,significant grain growth((112±76)μm.followed by a non-uniform.structure was observed after annealing at 1050℃and resulted in the lowest corrosion resistance(1.3 kΩ·cm.(2)).

关键词： corrosion texture m.crostructure therm.m.chanical processing stainless steel

Producing High Intense Attosecond Pulse Train by Interaction of Three-Color Pulse and Overdense Plasm.

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Chinese Physics Letters 2017年第5期34卷 52-55页

作者： m.salehi S.m.rzanejad Departm.nt of Atom.c and m.lecular Physics University of Mazandaran

Am.lifying the attosecond pulse by the chirp pulse am.lification m.thod is im.ossible. Furtherm.re, the intensity of attosecond pulse is low in the interaction of laser pulse and underdense plasm.. This m.tivates us to propose using a m.lti-color pulse to produce the high intense attosecond pulse. In the present study, the relativistic interaction of a three-color linearly-polarized laser-pulse with highly overdense plasm. is studied. We show that the com.ination of ω1, ω2 and ω3 frequencies decreases the instance full width at half m.xim.m.reflected attosecond pulse train from.the overdense plasm. surface. m.reover, we show that the three-color pulse increases the intensity of generated harm.nics, which is explained by the relativistic oscillating m.rror m.del. The obtained results dem.nstrate that if the three-color laser pulse interacts with overdense plasm., it will enhance two orders of m.gnitude of intensity of ultra short attosecond pulses in com.arison with m.nochrom.tic pulse.

关键词： Producing High Intense Attosecond Pulse Train by Interaction of Three-Color Pulse and Overdense Plasm.

The Influence of the Dependence of Surface Energy Coefficient to Tem.erature in the Proxim.ty m.del

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Chinese Physics Letters 2013年第4期30卷 55-59页

作者： m.salehi O.N.Ghodsi Sciences Faculty Department of PhysicsQaemshahr BranchIslamic Azad UniversityP.O.Box 163QaemshahrIran Sciences Faculty Department of PhysicsUniversity of MazandaranP.O.Box 47415-416BabolsarIran

We introduce a new surface energy coefficient in proxim.ty form.lism.which is dependent on tem.erature,and apply it to a system.tic study of barrier height and *** proxim.ty m.del can effectively predict the barrier heights and positions,as well as the fusion cross sections,over a wide range of incident energies,especially in light-heavy nuclei interaction.

关键词： interaction. proxim.ty apply