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Effects of microstructure and texture after thermomechanical treatments 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 Department of materials Science and Engineering Faculty of EngineeringShahid Chamran University of AhvazAhvaz ***Iran

In the present study,the effects of microstructure,grain size,and texture after thermomechanical 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 temperature,followed by annealing at 750,950 and 1050℃for 15 *** occurred after annealing at 750℃,and with the increasing of annealing temperature to 950℃and 1050℃,secondary recrystallization(abnormal grain growth)and grain growth were *** results showed that,after 20%thickness reduction,corrosion resistance increased significantly(21.1 kΩ·cm^(2))compared with the as-received condition(3.9 kΩ·cm^(2))due to the enhancement 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 compared with the as-received *** annealing the 90%cold rolled(CR)specimens at 750 and 950℃,the corrosion resistance increased in comparison with the as-received sample as a result of the more uniform microstructure,appearance of Goss and brass texture components,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 microstructure thermomechanical processing stainless steel

The Influence of the Dependence of Surface Energy Coefficient to Temperature in the Proximity model

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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 proximity formalism,which is dependent on temperature,and apply it to a systematic study of barrier height and *** proximity model 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. proximity apply

Efficient energy absorption of functionally-graded metallic foam-filled tubes under impact loading

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Transactions of Nonferrous metals Society of China 2021年第1期31卷 92-110页

作者： m.salehi S.m.H.mIRBAGHERI A.JAFARI RAmIANI Department of materials and metallurgical Engineering Amirkabir University of TechnologyTehran 15875-4413Iran

The deformation behavior and crashworthiness of functionally-graded foam-filled tubes(FGFTs)under drop-weight impact loading were *** cell aluminum,A356 alloy and zinc foams fabricated by the liquid state processing were used as axial grading fillers for the manufacture of single-layer and multilayer structures with different *** results indicate that the deformation of multilayer foam filled tubes initiates from the low-strength components,and then propagates in the high-strength components through the gradual increment of *** use of more A356 alloy and aluminum foam layers provides greater specific energy absorption(SEA)for the graded structures,whereas the high-strength zinc foam has no positive effect on the crash *** progressive collapse of graded structures consisting of the aluminum and A356 alloy foams occurs in a symmetric mode under quasi-static and drop-weight impact ***,the zinc foam causes a combination of symmetric and extension modes as well as greater localized deformation under dynamic loading and greater local rupture in quasi-static loading *** Al−A356 foam-filled tubes with a combination of the highest SEA(10 J/g)and the lowest initial peak stress(σmax of 10.2 mPa)are considered as the best lightweight crashworthy structures.

关键词： functionally-graded foam-filled tube drop-weight impact deformation behavior specific energy absorption crashworthiness

Impact strength and structural refinement of A380 aluminum alloy produced through gas-induced semi-solid process and Sr addition

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Transactions of Nonferrous metals Society of China 2022年第5期32卷 1405-1415页

作者： m.HONARmAND m.salehi S.G.SHABESTARI H.SAGHAFIAN School of metallurgy and materials Engineering Iran University of Science and Technology(IUST)NarmakTehranIran

Semi-solid processing of A380 aluminum alloy was performed by gas induced semi-solid(GISS)*** effects of argon inert gas flow rate,starting temperature and duration of gas purging as key GISS parameters and also modification with Sr on the structural refinements,hardness and impact strength of GISS alloys were *** evolution shows that there is an important effect of the pouring temperature and Sr addition on the morphology and size of primaryα(A1)in the alloy to change from coarse dendritic to fine globular *** best sample which has fine grains of 51.18μm in average size and a high level of globularity of 0.89 is achieved from a GISS processing of Sr modified alloy in which the gas purging started at 610℃.The impact strength of the GISS optimized samples((4.67±0.18)J/cm^(2))shows an increase of about 40%with respect to the as-cast sample due to the globular structure and fibrous Si ***,the hardness of the optimized GISS sample((89.34±2.85)HB)increases to(93.84±3.14)HB by modification with the Sr and GISS *** fracture surface of Sr modified alloy is also dominated by complex topography showing typical ductile fracture features.

关键词： gas-induced semi-solid process impact strength A380 aluminium alloy globular structure modification

Influnce of Stoichiometry and molar Ratio of Barium Ferrite Thin Film Synthesized by Sol-gel on Alumina Substrate

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材料热处理学报 2004年第5B期25卷 1313-1315页

作者： AliGhasemi m.R.Shams A.Saatchi m.salehi A.Hosseinpour materialsEngineeringDepartment IsfahanuniversityofTechnologyIsfahanIran ElectroceramicResearchcenter ShahinshahrIran materialsEngineeringDepartment IsfahanuniversityofTechnologyIsfahanIran／／ElectroceramicResearchcenterShahinshahrIran

Amorphous gels were processed with a varying Fe/Ba ratio of 11/5, 28/2, 10.5/1 in water and Solvent. Iron and barium nitrites with specific molar ratio was solved in water and slovent at 60°C for 3 hours until! a dark brown solution was prepared . The sols were introduced to substrate dropwise and spinning with 2000 rpm in 3 min was applied ; the work was repeated for 10 times and the samples were dried and sintered . The TGA analysis was used to identify the heating rate of the samples; at temperature of 1150°c for one hour the final phase was attained . the thickness , uniformity , morphology and the composition were examined by SEm and XRD. The study shows that the fabrication barium ferrite film of the molar ratio of Fe/Ba = 10.5/1 is much more suitable than other ratios .

关键词：溶胶凝胶钡铁氧体摩尔比率氧化铝基片

Advancements in Fixed Point Theorems for α-Geraghty Contractions in Complete metric Space

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Journal of mathematical Research with Applications 2024年第5期 697-710页

作者： V.C.BORKAR mohammed m.A.TALEB Saeed A.A.AL-salehi School of mathematical at Yeshwant mahavidyalaya Swami Ramanand Teerth Marathwada University School of mathematical at Science College Swami Ramanand Teerth Marathwada University Department of mathematics Hodeidah University Department of mathematics Aden University

This article improves and advances the results achieved by Vishal and Naveen, leveraging the use of Lebesgue integrable functions. Going beyond, we investigate fixed point theorems associated with a concept introduced by Ovidiu Popescu. Our research not only bolsters the theoretical framework but also unveils practical applications in the domain of Lebesgue integrals as in Example 3.6. Furthermore, our contribution enhances the understanding of fixed point theorems in metric spaces and introduces novel perspectives in the study of generalized α-Geraghty contractive mappings on Lebesgue integrals.

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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 mashayekh-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_(mn))、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_(mn))、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_(mn)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 mg·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 Wiedemann–Franz law in a granular s-wave superconductor in the nanometer 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 Department of Physics Shahid Chamran University of Ahvaz Ahvaz Iran

The present study tries to evaluate the validity of the Wiedemann-Franz law in a granular s-wave superconductor in the presence of concentrated impurities. By using Green＇s function method and the Kubo formula technique, three distinct contributions of the Aslamazov-Larkin, the maid-Thompson and, the density of states are calculated for both the electrical conductivity and the thermal conductivity in a granular s-wave superconductor. It is demonstrated that these different con- tributions to the fluctuation conductivity depend differently on the tunneling because of their different natures. This study examines the transport in a granular superconductor system in three dimensions in the limit of large tunneling conductance, which makes it possible to ignore all localization effects and the Coulomb interaction. We find that the tunneling is efficient near the critical temperature and that there is a crossover to the characteristic behavior of a homogeneous system. When it is far from the critical temperature, the tunneling is not effective and the system behaves as an ensemble of real zero-dimensional grains. The results show that the Wiedemann-Franz law is violated in both temperature regions.

关键词： granular superconductor s-wave impurity vertex fluctuation propagator

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 Department of Radiological and Nuclear Engineering Science and Research Branch Islamic Azad University Department of Electrical Engineering Islamic Azad University South Tehran Branch

Bremsstrahlung photon beams produced by medical linear accelerators are currently the most commonly used method of radiation therapy for cancerous tumors. Photons with energies greater than 8-10 meV potentially generate neutrons through photonuclear interactions in the accelerator＇s treatment head, patient＇s body, and treat- ment room ambient. Electrons impinging on a heavy target generate a cascade shower of bremsstrahlung photons, the energy spectrum of which shows an end point equal to the electron beam energy. By varying the target thickness, an optimum thickness exists for which, at the given electron energy, maximum photon flux is achievable. If a source of high-energy photons i.e. bremsstrahlung, 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. Comparison and assessment of deuterium photonuclear cross section data. 2. Evaluation of the heavy water photonuclear source.

关键词： BNCT photoneutron source linac heavy water