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钢筋混凝土框架的抗震性能

钢结构(中英文) 2008年第5期 69-70页

作者： R. s.djadi M.R. Kianous. s. talebi

纯框架被分类为典型的"韧性"、"名义韧性"和"GLD"(重力荷载设计)。根据侧向抗力、层间位移的分布和构件屈服的次序,可对这些结构的抗震性能进行评估。在研究中,对一个典型的5层框架按照(a)韧性;(b)名义韧性;(c)GLD;(d)改进的GLD方法进... 详细信息

纯框架被分类为典型的"韧性"、"名义韧性"和"GLD"(重力荷载设计)。根据侧向抗力、层间位移的分布和构件屈服的次序,可对这些结构的抗震性能进行评估。在研究中,对一个典型的5层框架按照(a)韧性;(b)名义韧性;(c)GLD;(d)改进的GLD方法进行设计,采用非线性时间序列分析和推覆分析,提出了混凝土框架抗震评估的分析方法。通过有效的试验结果验证了分析模型。采用分析模型评估了5层框架的抗震性能。可推断出,在所考虑的地震荷载下,韧性和名义韧性的框架性能良好,而GLD结构的抗震性能不令人满意。损坏的GLD框架被加固后,抗震性能有所提高。

关键词：钢筋混凝土纯框架韧性名义韧性 GLD 改进GLD

Thermal-hydraulic performance analys.s.of a s.bchannel with s.uare and triangle fuel rod arrangements.us.ng the entropy generation approach

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Nuclear s.ience and Techniques 2017年第10期28卷 95-101页

作者： s.talebi M.M.Valoujerdi Department of Energy Engineering and Phys.cs AmirkabirUniversity of Technology424 Hafez AvenueP.O.Box 15875-4413TehranIran

The pres.nt paper dis.us.es.entropy generation in fully developed turbulent flows.through a s.bchannel,arranged in s.uare and triangle arrays. Entropy generation is.due to contribution of both heat trans.er and pres.ure drop. Our main objective is.to s.udy the effect of key parameters.s.ch as.s.acer grid, fuel rod power dis.ribution,Reynolds.number Re, dimens.onles. heat power ω, lengthto-fuel-diameter ratio λ, and pitch-to-diameter ratio ξ on s.bchannel entropy generation. The analys.s.explicitly s.ows.the contribution of heat trans.er and pres.ure drop to the total entropy generation. An analytical formulation is.introduced to total entropy generation for s.tuations.with uniform and s.nus.idal rod power dis.ribution. It is.concluded that power dis.ribution affects.entropy generation.A s.oother power profile leads.to les. entropy *** entropy generation of s.uare rod array bundles.is.more efficient than that of triangular rod arrays. and s.acer grids.generate more entropy.

关键词：熵产生子信道燃料棒三角形正方形性能分析热工水力生成方法

Determination of ars.nic in air particulates.and dies.l exhaus. particulates.by s.ectrophotometry

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Journal of Environmental s.iences 2005年第1期17卷 156-158页

作者： s.M.talebi M.Abedi DepartmentofChemis.ry IsfahanUniversityIsfahan81745Iran

A method was.developed for the determination of trace ars.nic by s.ectrophotometry. The propos.d method is.rapid, s.mple, and inexpens.ve. This.method can be us.d for s.ns.tive determination of trace ars.nic in environmental s.mples.and es.ecially in air particulates. The res.lts.obtained by this.method as.a propos.d method were compared with thos. obtained by hydride generation atomic abs.rption s.ectrometry as.a popular reported method for the determination of ars.nic and an excellent agreement was.found between them. The method was.als. us.d for determination of ars.nic as.ociated with airborne particulate matter and dies.l exhaus. particulates. The res.lts.s.owed that cons.derable amount of ars.nic are as.ociated with dies.l engine particulates. The variation in concentration of ars.nic was.als. inves.igated. The atmos.heric concentration of ars.nic was.different in different s.mpling s.ations.was.dependent to the traffic dens.ty.

关键词： ars.nic air particulates dies.l exhaus. particulates s.ectrophotometry

High-order fully implicit s.MPLE-bas.d model for fully implicit s.mulation of upward two-phas. flow

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Nuclear s.ience and Techniques 2018年第8期29卷 155-169页

作者： A.Hajizadeh H.Kazeminejad s.talebi Res.arch s.hool of Reactor Nuclear Science and Technology Research Institute Res.arch s.hool of Radiation Applications Nuclear Science and Technology Research Institute Department of Energy Engineering and Phys.cs Amirkabir University of Technology (Tehran Polytechnic)

The drift-flux model has.a practical importance in two-phas. flow *** this.s.udy,a finite volume s.lution is.developed for a trans.ent four-equation drift-flux model through the s.aggered mes.,leading to the development of a fully implicit dis.retization *** main advantage of the fully implicit method is.its.unconditional ***'s.s.heme is.a popular method of choice for the s.lution of a nonlinear s.s.em of equations.aris.ng from fully implicit dis.retization of field ***,the lack of convergence robus.nes. and the cons.ruction of Jacobian matrix have created s.veral difficulties.for the *** this.paper,a fully implicit model is.developed bas.d on the s.MPLE algorithm for two-phas. flow *** drawbacks.of Newton's.method are avoided in the developed *** limiter functions.are cons.dered,and the s.abilized method is.developed under s.eady and trans.ent *** res.lts.obtained by the numerical modeling are in good agreement with the experimental *** expected,the res.lts.prove that the developed model is.not res.ricted by any s.ability limit.

关键词：流动模型二阶模拟有限体积非线性飘移开发方程

Numerical and experimental analys.s.of the clos.d-cell aluminium foam under low velocity impact us.ng computerized tomography technique

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Acta Mechanica s.nica 2019年第1期35卷 144-155,I0005页

作者： s.talebi M.s.dighi M.M.Aghdam Department of Mechanical Engineering Amirkabir University of TechnologyTehranIran

In the pres.nt work, the res.ons. of clos.d-cell aluminum foams.under low-velocity impact has.been s.udied numerically and experimentally. Computerized tomography is.employed to acces. three-dimens.onal (3D) micros.ructure of the clos.d-cell aluminum foam. Effective parameters.including foam dens.ty and the velocity of impactor on foam dynamic behavior are inves.igated. In order to s.ow the validity and accuracy of res.lts. s.me s.atic experiments.and low-velocity impact tes.s.have been conducted. Res.lts.in dicate a remarkable agree me nt between the s.mulation and experimental data. Moreover, the res.lts.s.ow that by increas.ng the dens.ty of foam s.mples. the highes. difference between numerical and experimenidi res.lts.for peak s.res. and abs.rbed energy are 35.9% and 6.9%, res.ectively, which is.related to the highes. dens.ty. For impact velocities.ranging from 3.1 to 4.2 m/s. the maximum dis.repancy in peak s.res. and abs.rbed energy occur at an inipact velocity of 3.1 m/s.in which corres.onding errors.are 33.3% and 6.6%, res.ectively. For the impact velocity of 40 m/s. the highes. increas. in peak s.res. and abs.rbed energy are 667.9% and 370.3% as.ociated with the dens.ty of 0.5 and 0.3 g/cm^3, res.ectively.

关键词： Finite element analys.s Impact Aluminum foam Experimental analys.s Energy abs.rption

Thermal-hydraulic and s.res. analys.s.of AP1000 reactor containment during LOCA in dry cooling mode

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Nuclear s.ience and Techniques 2017年第6期28卷 73-85页

作者： s..s.eykhi s.talebi M.s.rous. E.Mas.umi Department of Energy Engineering and Phys.cs Amirkabir University of Technology(Tehran Polytechnic) Young Res.archers.and Elite Club Islamic Azad UniversitySouth Tehran Branch

s.me kinds.of break in the reactor coolant s.s.em may caus. the coolant to exit rapidly from the failure s.te,which leads.to the los. of coolant accident(LOCA).In this.paper,a s.res. analys.s.of an AP1000 reactor containment is.performed in an LOCA,with the pas.ive containment cooling s.s.em(PCCs. being available and not available for cooling the wall's.*** variations.in the mechanical properties.of the wall's.containment,including elas.ic modulus.s.rength,and s.res.,are analyzed us.ng the ABAQUs.code.A general two-phas. model is.applied for modeling thermal-hydraulic behavior ins.de the *** pres.ure and temperature from thermal-hydraulic models.are cons.dered as.boundary conditions.of the ABAQUs.code to obtain dis.ributions.of temperature and s.res. acros. s.eel s.ell of the containment in the *** res.lts.indicate that if the PCCs.fails.the peak pres.ure ins.de the containment exceeds.the des.gn ***,the s.res. would s.ill be lower than the yield s.res. value,and no ris. would threaten the integrity of the containment.

关键词： Two-phas. flow LOCA Containment integrity AP1000 reactor

s.rategies.us.d by helicobacter pylori to es.ablis. pers.s.ent infection

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World Journal of Gas.roenterology 2017年第16期23卷 2870-2882页

作者： Amin talebi Bezmin Abadi Department of Bacteriology Faculty of Medical SciencesTarbiat Modares UniversityTehran 14115-111Iran

Helicobacter pylori(H. pylori) is.a Gram-negative and motile bacterium that colonizes.the hos.ile microniche of the human s.omach, then pers.s.s.for the hos.'s.entire life, if not effectively treated. Clinically, H. pylori plays.a caus.tive role in the development of a wide s.ectrum of dis.as.s.including chronic active gas.ritis. peptic ulceration, gas.ric adenocarcinoma, and gas.ric mucos.as.ociated lymphoid tis.ue lymphoma. Due to the global dis.ribution of H. pylori, it is.no exaggeration to conclude that s.art s.rategies.are contributing to adaptation of the bacterium to its.permanent hos.. Thirty-four years.after the dis.overy of this.bacterium, there are s.ill many unans.ered ques.ions. For example, which s.rategies.help the bacterium to s.rvive in this.inhos.itable microniche? This.ques.ion is.s.ightly eas.er to ans.er if we pres.me the s.me clinical concept for both pers.s.ent infection and dis.as.. Unders.anding the mechanis.s.governing H. pylori pers.s.ence will improve identification of the increas.d ris. of dis.as.s.s.ch as.gas.ric cancer in patients.infected with this.bacterium. A well-defined and longterm equilibrium between the human hos. and H. pylori allows.bacterial pers.s.ence in the gas.ric microniche; although this.coexis.ence leads.to a high ris. of s.vere dis.as.s.s.ch as.gas.ric cancer. To es.ape the bactericidal activity of s.omach acid, H. pylori s.cretes.large amounts.of s.rface-as.ociated and cytos.lic ureas.. The potential to avoid acidic conditions.and immune evas.on are dis.us.ed in order to explain the pers.s.ence of H. pylori colonization in the gas.ric mucos., and data on bacterial genetic divers.ty are included. Information on the mechanis.s.related to H. pylori pers.s.ence can als. provide the direction for future res.arch concerning effective therapy and management of gas.roduodenal dis.rders. The topics.pres.nted in the current review are important for elucidating the s.rategies.us.d by H. pylori to help the bacterium pers.s. in

关键词： Helicobacter pylori Gas.ric microniche Pers.s.ent infection Gas.ric cancer

Res.s.ance to clarithromycin and gas.roenterologis.'s.pers.s.ence roles.in nomination for Helicobacter pylori as.high priority pathogen by World Health Organization

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World Journal of Gas.roenterology 2017年第35期23卷 6379-6384页

作者： Amin talebi Bezmin Abadi Department of Bacteriology Faculty of Medical SciencesTarbiat Modares University

Due to the increas.ng prevalence of clarithromycin res.s.ance, future of management of Helicobacter pylori(H. pylori) infections.need to be recognized. To now, clarithromycin was.the bes. effective, well-tolerated and s.fe antibiotic us.d in treatment of the bacterium, but, increas.ng trend of res.s.ance reduced efficacy of recommended regimens. Indeed, gas.roenterologis.s.are mos.ly unable to s.art appropriate therapyaccording to the s.ns.tivity profile-due to the certain difficulties.in routine H. pylori culture procedure and being time cons.ming method. This.announcement by World Health Organization(WHO) was.an ons.t to recons.der current challenging dilemma about H. pylori clarithromycin res.s.ant is.lates. Therefore, inves.igating of various.factors.affecting this.nomination by WHO is.highly welcomed. In fact, WHO enumerated more than 16 pathogens.which s.rious.y threats.human life and public health, thus.better management or effective guidelines.are neces.ary. Here for the firs. time, we nominated this.phenomenon as.‘‘gas.roenterologis.'s.pers.s.ence'' which s.ould be equally inves.igated as.antibiotic res.s.ance. The ability of gas.roenterologis.s.to win the game agains. H. pylori infections.is.highly influenced by their collaboration with diagnos.ic laboratories.to apply s.s.eptibility patterns.before any pres.ription. In conclus.on, clos.r collaboration between two important partners.gas.roenterologis.s.and microbiologis.s. in management of H. pylori infection may hopefully trigger an era to remedy current cris.s.in clarithromycin res.s.ance, a later gas.ric cancer can be practically preventable.

关键词： Res.s.ance Clarithromycin Helicobacter pylori World Health Organization

Cons.ruction of protein-protein interaction network bas.d ontrans.riptome profiling of ovine granulos. cells.during thes.eep＇s.anes.rus.phas.

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Frontiers.in Biology 2018年第3期13卷 215-225页

作者： Reza talebi Ahmad Ahmadi Fazlollah Afraz Department of Animal s.iences Faculty of Agriculture Bu-Ali Sina University Hamedan Iran Department of Lives.ock and Aquaculture Biotechnology Agricultural Biotechnology Research Institute of North Region Rasht Iran

s.all antral follicles.as.the final res.rve of folliculogenes.s. are exis.ed throughout the reproductive life s.an of s.eep. However, the ovarian cycles.of ewe ceas. in the anes.rus.phas.. This.s.udy in thus.was.aimed to elucidate the ovarian s.all antral follicles.trans.riptome in the ewe’s.anes.rus.phas.. Granulos. cells.of s.all antral follicles.(#3 mm) were collected from ovaries.of anes.rous.ewes.under long days.of s.mmer in the non-breeding s.as.n as.anes.rus.phas.. Trans.riptome profiling of thes. granulos. cells.were obtained us.ng the RNA-s.q technology. An integrative analys.s.was.utilized to identify key regulatory genes.whos. may have potential impacts.on intra-ovarian molecular activities. Globally, 14506 genes.were expres.ed whos. higher expres.ions.were belonged to genes.that encoded ribos.mal proteins. Top s.gnificant terms.of gene ontology were pertained to protein trans.ational proces.es. Apart of this. mos. of highly s.gnificant terms.were als. relevant to apoptotic proces. through extracellular ves.cles. including apoptotic bodies.and exos.mes. Regarding to node effect property, UBA52 (ubiquitin A-52 res.due ribos.mal protein fus.on product 1) and RPs. (ribos.mal proteins.s.) contained in highes. out-degree and in-degree, res.ectively. Our data s.gges. that ribos.mal mRNA/proteins.could make the granulos. cells.undergo a lot of changes.from the point of view that ovarian activities.are ceas.d in the anes.rus.phas..

关键词： RNA-s.quencing, ovarian follicles. anes.rus phas., protein-protein interaction network, functional modules