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A new approach for free vibration analysis of a system of elastically interconnected similar rectangular plates

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earthquake engineering and engineering Vibration 2022年第4期21卷 947-967页

作者： e.heidari A.Ariaei Department of Mechanical engineering Faculty of EngineeringUniversity of IsfahanIsfahan ***Iran

A new procedure is proposed to ease the analyses of the free vibration of an elastically connected identical plates system with respect to Kirchhoff plate theory.A structure of n parallel,elastically connected rectangular plates is of concern,whereby the motion is explained by a set of n coupled partial differential *** method involves a new change in variables to uncouple equations and form an equal system of n decoupled plates,while each is assumed to be elastically connected to the *** differential quadrature method is adopted to solve the decoupled *** unravel the original system,the inverse transform is *** the equations enables one to solve them based on the solution methods available for a single plate *** also diminishes the computational costs of such *** considering different boundary conditions,a case study is run to present the method and to validate the results with its counterparts,for which excellent agreement is *** the influence of dimensionless thickness,aspect ratio,and stiffness coefficients on the frequencies reveals the different effects of them at the low order of dimensionless natural frequencies in comparison with high orders and for different boundary conditions.

关键词： multiple-plate system elastic connections free vibration Kirchhoff plate theory differential quadrature method

effect of Phase Transformation During Long-Term Solution Treatment on Microstructure,Mechanical Properties,and Bio-corrosion Behavior of Mg–5Zn–1.5Y Cast Alloy

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Acta Metallurgica Sinica(english Letters) 2018年第6期31卷 561-574页

作者： H.Jafari e.heidari A.Barabi M.Dashti Kheirabadi Materials engineering Department Faculty of Materials Engineering and Modern TechnologiesShahid Rajaee Teacher Training University

The influence of long-term solution treatment for various intervals on the microstructure,mechanical properties,and corrosion resistance of the as-cast Mg–5Zn–1.5Y alloy was *** of secondary phases was studied during solution treatment through thermal analysis test and thermodynamic *** and hardness tests,as well as polarization and immersion tests,were performed to evaluate the mechanical properties and corrosion behavior of the ascast and heat-treated alloy,*** show that solution treatment transforms I-phaseinto W-phaseas well as dissolves it into the a-Mg matrix to some extent;therefore,the amount of W-phase ***,prolonged solution treatment decreases the volume fraction of the *** the first stage of solution treatment for 14 h,the tensile properties significantly increase due to the incomplete phase *** long-term solution treatment sharply decreases the tensile and hardness properties of the alloy,it improves the corrosion resistance due to the transformation of I-phase into *** fact,it decreases corrosion potential and simultaneously dissolves intermetallic compounds into the a-Mg matrix,resulting in the reduction in galvanic microcells between the matrix and *** is found that the optimum time for long-term solution treatment is 14 h,which improves both corrosion behavior and mechanical properties.

关键词： Magnesium alloy Long-term solution treatment Microstructure Mechanical properties Bio-corrosion

Stabilization of saline silty sand using lime and micro silica

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Journal of Central South University 2012年第10期19卷 3006-3011页

作者： R.Z.Moayed e.Izadi S.heidari Department of Civil engineering Imam Khomeini International UniversityQazvin 34149-16818Iran

Many construction and post-construction problems have been reported in the literature when saline soils have been used without understanding of their abnormal behavior,especially their inferior bearing capacity in the natural *** strength of these soils further decreases on *** soil deposits cover extensive areas in central Iran and are associated with geotechnical problems such as excessive differential settlement,susceptibility to strength loss and collapse upon *** of these characteristics,some of the roads constructed on saline soils in Taleghan area have exhibited deterioration in the form of raveling,cracking and *** main objective of this work is to improve the load-bearing capacity of pavements constructed on Taleghan saline soils using lime and micro *** samples from Hashtgerd-Taleghan road were collected and tested for improving their properties using lime and micro silica at different dosages ranging from 0 to 6%.The load-bearing capacity of stabilized soil mixtures was evaluated using California Bearing Ratio(CBR) and unconfined compressive strength *** test results indicate that the lime improves the performance of soil *** addition of 2% lime with 3% micro silica has satisfied the strength-deformation ***,improved soil can be used as a good subbase in flexible pavements.

关键词： lime stabilization saline soil micro silica bearing capacity compressive strength flexible pavements

effects of environmental factors on classification of loessderived soils and clay minerals variations, northern Iran

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Journal of Mountain Science 2018年第5期15卷 976-991页

作者： Mohammad AJAMI Ahmad heidari Farhad KHORMALI Manouchehr GORJI Shamsollah AYOUBI Department of Soil Science College of Agriculture and Natural Resources University of Tehran Department of Soil Science Faculty of Water and Soil Engineering Gorgan University of Agricultural Sciences and Natural Resources Department of Soil Science College of Agriculture Isfahan University of Technology

Land-use type under different topographic conditions and human activities affects soil development. We investigated the effects of land-use,topography and human activity on soil classification changes in the Toshan watershed in northern *** representative pedons derived from loess parent materials were studied on different land-uses and topographic positions. The studied pedons in forest(FO) on backslopes and footslope were classified as Calcic Haploxeralfs and Typic Haploxeralfs, respectively. The soils in abandoned lands(AB) and orchards(OR), where formerly under natural forests, located on the shoulder and backslopes positions were classified as Calcic Haploxeralfs and Vertic Haploxeralfs, ***-developed argillic horizons as indicators for higher degrees of soil evolution were observed in more-stable areas under the natural forest or less disturbed areas. Clay lessivage through these soil profiles have led to formation of Typic or Calcic Haploxeralfs, while under croplands(CP) were classified as Typic Calcixerepts. Conversion of sloping deforested areas to CP along with inappropriate management have accelerated soil erosion, resulting in unstable conditions in which decalcification and formation of developed soils cannot occur. Paddy cultivation in flat areas has caused to reduced conditions and formation of Typic *** of unfavorable conditions for chemical weathering(e.g. lower water retention compared to more-stable areas) no vermiculite was detected in the CP. The results showed that evolution and classification of the studied soils were strongly affected by land-use type, topography and management.

关键词： Soil classification Clay mineralogy Land-use change Topography Loess

Modeling and process optimization for microbial desulfurization of coal by using a two-level full factorial design

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International Journal of Mining Science and Technology 2013年第2期23卷 266-270页

作者： Golshani T. Jorjani e. Chelgani S. Chehreh Shafaei S.Z. Nafechi Y. heidari Department of Mining engineering Science and Research Branch Islamic Azad University Young Researchers and elites club Science and Research Branch Islamic Azad University School of Mining engineering University of Tehran

The microbial sulfur removal was investigated on high sulfur content (1.9%) coal concentrate from Tabas coal preparation plant. A mixed culture of ferrooxidans microorganisms was isolated from the tailing dam of the plant. Full factorial method was used to design laboratory test and to evaluate the effects of pH, particle size, iron sulfate concentration, pulp density, and bioleaching time on sulfur reduction. Statistical analyses of experimental data were considered and showed increases of pH and particle size had negative effects on sulfur reduction, whereas increases of pulp density and bioleaching time raised microbial desulfurization rate. According to results of designing, and regarding statistical factors, the optimum values for maximum sulfur reduction were obtained; pH (1.5), particle size (-180 μm), iron sulfate concentration (2.7 mmol/L), pulp density (10%) and bioleaching time (14 d), which leaded to 51.5% reduction from the total sulfur of sample.

关键词： Coal Microbial desulfurization Ferrooxidant microorganisms Statistical technique

The potential of gene therapies for spinal cord injury repair:a systematic review and meta-analysis of pre-clinical studies

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Neural Regeneration Research 2023年第2期18卷 299-305页

作者： Catriona J.Cunningham Mindaugas Viskontas Krzysztof Janowicz Yasmin Sani Malin eHåkansson Anastasia heidari Wenlong Huang Xuenong Bo Institute of Medical Sciences School of MedicineMedical Sciences&NutritionUniversity of AberdeenAberdeenUK Centre for Neuroscience Surgery and TraumaBlizard InstituteBarts and the London School of Medicine and DentistryQueen Mary University of LondonLondonUK

Currently,there is no cure for traumatic spinal co rd injury but one therapeutic approach showing promise is gene *** this systematic review and meta-analysis,we aim to assess the efficacy of gene therapies in pre-clinical models of spinal cord injury and the risk of *** this metaanalysis,registe red at PROSPeRO(Registration ID:CRD42020185008),we identified relevant controlled in vivo studies published in english by searching the PubMed,Web of Science,and embase *** restrictions of the year of publication were applied and the last literature search was conducted on August 3,*** then conducted a random-effects meta-analysis using the restricted maximum likelihood estimator.A total of 71 studies met our inclusion crite ria and were included in the systematic *** results showed that overall,gene therapies were associated with improvements in locomotor score(standardized mean difference[SMD]:2.07,95%confidence interval[CI]:1.68-2.47,Tau^(2)=2.13,I^(2)=83.6%)and axonal regrowth(SMD:2.78,95%CI:1.92-3.65,Tau^(2)=4.13,I^(2)=85.5%).There was significant asymmetry in the funnel plots of both outcome measures indicating the presence of publication *** used a modified CAMARADeS(Collaborative Approach to M eta-Analysis and Review of Animal Data in experimental Studies)checklist to assess the risk of bias,finding that the median score was 4(IQR:3-5).In particula r,reports of allocation concealment and sample size calculations were *** conclusion,gene therapies are showing promise as therapies for spinal co rd injury repair,but there is no consensus on which gene or genes should be targeted.

关键词： animal models gene delivery meta-analysis regenerative medicine spinal cord injury systematic review viral vectors

冷轧及退火对310S奥氏体不锈钢的微观结构和组织的影响:基于X射线和电子背散射衍射分析

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Journal of Central South University 2023年第3期30卷 763-785页

作者： R.B.heidari M.eSKANDARI M.YeGANeH Department of Materials engineering Faculty of EngineeringShahid Chamran University of AhvazAhvaz ***Iran

本文研究了热处理对310S奥氏体不锈钢的微观结构和组织的影响。对样品材料进行冷轧,使其厚度分别减少20%、50%和90%,然后在1023、1223和1323 K下退火5、15和30 min。在厚度减少20%后,奥氏体内产生孪晶,且可观察到形变诱发的α’马氏体,... 详细信息

本文研究了热处理对310S奥氏体不锈钢的微观结构和组织的影响。对样品材料进行冷轧,使其厚度分别减少20%、50%和90%,然后在1023、1223和1323 K下退火5、15和30 min。在厚度减少20%后,奥氏体内产生孪晶,且可观察到形变诱发的α’马氏体,孪晶的体积分数大于α’马氏体。当厚度变化由50%增加到90%,α’马氏体的体积分数由11%增加到69%,孪晶被α’马氏体取代。发生形变后奥氏体相主要为Brass、Goss和S织构,α’马氏体的主要纹理为R-Cu、R-cube、F和e组份。随着形变量增大,Brass织构增加,Goss织构减少。退火过程中,马氏体向奥氏体转变,并发生了再结晶,使Goss和Brass再结晶织构的体积分数增加。材料退火后的结构与冷轧后的大致相同。1223 K下退火5 min的马氏体转变速度明显高于1023 K下的。在1023 K下退火5 min,由于马氏体不完全转变和初级再结晶,未能检测到等轴组织。获得超细晶粒组织的最佳退火温度为1023 K,退火时间为15 min。在1173 K和1273 K时出现快速再结晶和晶粒生长。

关键词： 310S不锈钢形变退火电子背散射衍射微观结构组织

Maximally entangled States in the Hydrogen Molecule: The Role of Spin and Correlation

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Journal of Modern Physics 2011年第7期2卷 664-668页

作者： Mohammad Ali Vesaghi Mohsen Babamoradi Mehdi heidari Saani 不详

Many electron calculations on a simplest realistic two electron system i.e. H2molecule was applied and as the consequence correlation effects was reflected accurately in the wavefunctions of H2. Zanardi’s entanglement measurement, demonstrated that the maximum of entanglement for the ground state happens when U =J and this resolved the controversial conclusion of U = 0 for maximum entanglement. It was shown that the ground and third excited states are maximally entangled. These maximally entangled states and also the minimally entangled states are correlated to their spin’s property. The wavefunctions of the not magnetic (S = 0) ground and excited states explicitly depend on correlation parameters whereas the first excited states which is magnetic (S2 = 2 and Sz≠0) is not entangled. The second excited state is not magnetic but its wavefunction does not depend on correlation parameters therefore it is a moderately entangled state. In any case, by switching on a magnetic field an entangled state with Sz = 0 can be extracted from a not entangled degenerate magnetic state. We suggest that in a realistic molecular scale system, there is two criteria for finding maximally entangled electronic states, first the system should be in moderately correlated regime and second the system should have a non-magnetic (Sz = 0) electronic state.

关键词： Hubbard Model entanglement Hydrogen Molecule

Investigation of litigation in trauma orthopaedic surgery

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World Journal of Clinical Cases 2023年第5期11卷 1000-1008页

作者： Maryam Salimi Mohammad Bagher heidari Zohre Ravandi Seyedarad Mosalamiaghili Peyman Mirghaderi Meisam Jafari Kafiabadi Farsad Biglari Amirhossein Salimi Amir Sabaghzadeh Irani Seyyed Saeed Khabiri Department of Orthopaedic Surgery Shiraz University of Medical SciencesShiraz ***Iran Department of General Surgery Kermanshah University of Medical SciencesKermanshah ***Iran Student Research Committee Kermanshah University of Medical SciencesShiraz ***Iran Student Research Committee Shiraz University of Medical SciencesShiraz 716549834Iran Students’Scientific Research Center(SSRC) Tehran University of Medical SciencesTehran 714356743Iran Clinical Research Development Unit of Shohada-e Tajrish Hospital Shahid Beheshti University of Medical SciencesTehran 715643498Iran Student Research Committee Shahid Sadoughi University of Medical SciencesYazd 719167534Iran

BACKGROUND It has been said that the number of orthopaedic claims has increased in the last few years. Investigation through the most prevalent cause would help to prevent further *** To review the cases of medical complaints in orthopedic patients who had been involved in a traumatic *** A retrospective multi-center review of trauma orthopaedic-related malpractice lawsuits from 2010 to 2021 was conducted utilizing the regional medicolegal database. Defendant and plaintiff characteristics along with fracture location, allegations, and litigation outcomes were *** A total of 228 claims referred to trauma-related conditions with a mean age of 31.29 ± 12.56 were enrolled. The most common injuries were at hand, thigh, elbow, and forearm, ***, the most common alleged complication was related to malunion or nonunion. In 47% of the cases, the main problem that led to the complaint was the inappropriate or insufficient explanation to the patient, and in 53%, there was a problem in the surgery. eventually, 76% of the complaints resulted in a defense verdict, and 24% resulted in a plaintiff *** Surgical treatment of hand injuries and surgery in non-educational hospitals received the most complaints. The majority of litigation outcomes were caused by a physician’s failure to fully explain and educate the traumatic orthopedic patients and technological errors.

关键词： Clinical negligence Litigation Medicolegal claims Mismanagement Patient satisfaction