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Transactions of Nonferrous Metals Society of China 2022年

作者： Amir Arsalan SHAYANPOOR hamid reza rezaei ashtiani School of Mechanical Engineering， Arak University of Technology

In this paper， the hot deformation behavior of Al/Cu bimetal composites was investigated using isothermal compression tests at temperatures of 400–500 ℃， strain rates of 0.001–0.1 s-1by considering the effects of volume fractions of composite components (30%-51% Al). In this regard， new proper constitutive equations were developed using Arrhenius-type and the rule of mixture (ROM) models. Experimental flow stress (FS) showed that processing parameters and volume fraction affect the flow behavior of composite as the volume fraction of copper has a more substantial impact on the flow behavior of the composite rods at elevated temperatures. The values of correlation coefficient (R) and average relative error percentage of the developed Arrhenius-type constitutive equation and ROM model were 0.9826， 0.9742， and 0.9718， and also 0.18%， 1.69%， and -0.84% for volume fractions of 51， 42， and 30% Al， respectively. The results indicate that the newly developed constitutive model can successfully predict the hot working behavior of the considered bimetal composite. Finally， the microstructure of composites was investigated under different processing conditions. The dominant mechanisms for three considered volume fractions were identified at different ranges of temperature， strain， and strain rate specified for the hot deformation of the Al/Cu composite.

关键词：

不同成分铝/铜双金属复合材料的热变形行为及其本构模型

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Transactions of Nonferrous Metals Society of China 2023年第12期33卷 3641-3660页

作者： Amir Arsalan SHAYANPOOR hamid reza rezaei ashtiani School of Mechanical Engineering Arak University of TechnologyArakIran

通过等温压缩实验,研究Al/Cu双金属复合材料在400~500℃、应变速率0.001~0.1 s^(-1)条件下的热变形行为,并考虑复合材料成分体积分数(Al含量为30%~51%)的影响。采用Arrhenius模型和混合定律(ROM)模型建立新的本构方程。流变应力(FS)实... 详细信息

通过等温压缩实验,研究Al/Cu双金属复合材料在400~500℃、应变速率0.001~0.1 s^(-1)条件下的热变形行为,并考虑复合材料成分体积分数(Al含量为30%~51%)的影响。采用Arrhenius模型和混合定律(ROM)模型建立新的本构方程。流变应力(FS)实验表明,工艺参数和体积分数对复合材料的流变行为有影响,而Cu的体积分数对复合材料的高温流变行为影响更大。对于体积分数为51%、42%和30%Al的复合材料,建立的Arrhenius型本构方程和ROM模型的相关系数(R)分别为0.9826、0.9742和0.9718,其平均相对误差分别为0.18%、1.69%和-0.84%。结果表明,新建立的本构模型能较好地预测双金属复合材料的热加工行为。最后,研究不同工艺条件下复合材料的显微组织,确定三种不同成分Al/Cu复合材料在不同温度、应变和应变速率范围内的主要热变形机制。

关键词：铝/铜双金属复合材料热变形混合定律(ROM) 本构方程力学行为显微组织

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Prediction of the Microstructural Variations of Cold-Worked Pure Aluminum during Annealing Process

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Modeling and Numerical Simulation of Material Science 2015年第1期5卷 1-14页

作者： hamid reza rezaei ashtiani Peyman Karami School of Mechanical Engineering Arak University of Technology Arak Iran

The mechanical properties such as hardness and ultimate tensile strength of metals depend on the grain size, which have to be properly controlled and optimized to ensure the better economy and desirable mechanical characteristics of the metals. In order to study the microstructure evolution of AA1070, many experimental tests were conducted at different cold working and annealing conditions. Utilizing the experimental results, the static recrystallization and grain growth behavior of AA1070 have been investigated and the developed equations that can be used to the FEM of the annealing process have been obtained. The agreement between numerical modeling and experimental results is reasonably good for this material. The results showed that the recrystallization and grain growth behavior of AA1070 was evidently affected by both the annealing temperature and plastic strain.

关键词： Grain Size Annealing Static Recrystallization Grain Growth FEM

Characteristics of turbulent flow in 3-D pools in the presence of submerged rigid vegetation in channel bed

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Journal of Hydrodynamics 2024年第1期36卷 158-169页

作者： Kourosh Nosrati Hossein Afzalimehr Jueyi Sui hamid reza Reisifar Natural Disasters Prevention Research Center Faculty of Civil EngineeringIran University of Science and TechnologyTehranIran School of Engineering University of Northern British ColumbiaPrince GeorgeCanada

In this study,the interaction between 3-D bedforms and submerged rigid vegetation has been *** laboratory experiments were conducted to study the distribution of flow velocity,Reynolds shear stress,turbulent kinetic energy,and skewness coefficients for a constant density of *** showed that the velocity profile in the pool section deviates from those in the upstream section of the *** has been found that the dip parameter varied between 0.6H and 0.9H depending on various factors including bed roughness,vegetation distribution,and pool entrance/exit ***,scattered vegetation in the pool and differences in slopes created non-uniform flow ***,in the wake region behind each vegetated element,flow velocity reduced significantly,and small-scale eddies are formed,causing increased *** decreasing the entrance slope and bed roughness,relatively uniform flow and weaker turbulence was resulted,but the random distribution of vegetated elements counteracted this balance and intensified *** the decrease in the pool entrance slope,the contribution of sweep event decreased and the contribution of ejection event increased.

关键词： Submerged rigid vegetation 3-D pool Reynolds shear stress skewness coefficients

Evolution of biomass particles during pelletization process

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Particuology 2024年第3期86卷 182-187页

作者： hamid rezaei Maryam Tajilrou Jun Sian Lee Kanages Singaraveloo Anthony Lau Shahab Sokhansanj Biomass and Bioenergy Research Group Department of Chemical and Biological EngineeringUniversity of British ColumbiaVancouverCanada

Pulverizing is an essential unit operation in co-firing biomass with *** are only compatible with pellet forms of fibrous biomass materials and crush them down to their original forming particle *** is why the data on the size distribution of the particles forming a biomass pellet is crucial to achieving optimum combustion *** current study determines the internal particle size distribution of pellets after wet disintegration,following Iso 17830 standard,and aims to suggest improvements to the mentioned standard based on new measured *** were carried out on white wood pellets(no bark)and brown wood pellets containing bark at four water temperatures:20,40,60,and 95℃,with or without *** particle size distribution of the pre-pelletizer wood particles was also measured and compared with particles in the formed *** water temperature of 20℃ was found to be adequate for the complete disintegration of pellets,and no mechanical stirring was *** 30% of particles in the disintegrated pellets were 0.5-1.0 *** changes the particle size distribution to smaller *** disintegrated bark pellets contained more fines than white pellets.

关键词： Wood pellets Particle sizes distribution Wet disintegration Stirring Water temperature

AGGREGATE SPECIAL FUNCTIONS TO APPROXIMATE PERMUTING TRI-HOMOMORPHISMS AND PERMUTING TRI-DERIVATIONS ASSOCIATED WITH A TRI-ADDITIVEψ-FUNCTIONAL INEQUALITY IN BANACH ALGEBRAS

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Acta Mathematica Scientia 2024年第1期44卷 311-338页

作者： Safoura rezaei ADERYANI Azam AHADI reza SAADATI Hari M.SRIVASTAVA School of Mathematics Iran University of Science and TechnologyNarmakTehranIran Department of Mathematics and Statistics Universtity of VictoriaVictoriaCanada Department of Medical Research China Medical University HospitalChina Medical UniversityTaichung40402China Department of Mathematics and Informatics Azerbaijan University71 Jeyhun Hajibeyli StreetAZ1007BakuAzerbaijan Section of Mathematics International TelematicUniversity UninettunoI-00186RomeItaly

In this paper,we define a new class of control functions through aggregate special *** class of control functions help us to stabilize and approximate a tri-additiveψ-functional inequality to get a better estimation for permuting tri-homomorphisms and permuting tri-derivations in unital C*-algebras and Banach algebras by the vector-valued alternative fixed point theorem.

关键词： permuting tri-homomorphism in Banach algebra permuting tri-derivation on C*-algebra fixed point theorem Ulam-Hyers-Rassias stability aggregate special functions tri-additiveψ-functional inequality

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Effect of CO_(2)exposure on the mechanical strength of geopolymerstabilized sandy soils

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 670-681页

作者： hamid reza Razeghi Armin Geranghadr Fatemeh Safaee Pooria Ghadir Akbar A.Javadi School of Civil Engineering Iran University of Science and TechnologyTehran***Iran Department of Engineering University of ExeterExeterEX44QFUK

In recent years,there has been growing interest in developing methods for mitigating greenhouse effect,as greenhouse gas emissions continue to contribute to global temperature *** the other hand,investigating geopolymers as environmentally friendly binders to mitigate the greenhouse effect using soil stabilization has been widely ***,the effect of CO_(2)exposure on the mechanical properties of geopolymer-stabilized soils is rarely *** this context,the effect of CO_(2)exposure on the mechanical and microstructural features of sandy soil stabilized with volcanic ash-based geopolymer was *** factors were concerned,for example the binder content,relative density,CO_(2)pressure,curing condition,curing time,and carbonate *** results showed that the compressive strength of the stabilized sandy soil specimens with 20%volcanic ash increased from 3 MPa to 11 *** was also observed that 100 kPa CO_(2)pressure was the optimal pressure for strength development among the other *** mechanical strength showed a direct relationship with binder content and carbonate ***,in the ambient curing(AC)condition,the mechanical strength and carbonate content increased with the curing ***,the required water for carbonation evaporated after 7 d of oven curing(OC)condition and as a result,the 14-d cured samples showed lower mechanical strength and carbonate content in comparison with 7-d cured ***,the rate of strength development was higher in OC cured samples than AC cured samples until 7 d due to higher geopolymerization and carbonation rate.

关键词： Soil stabilization CO_(2)effect Geopolymer

Exploring the relationship between ambient sulfur dioxide and semen quality parameters:A systematic review and meta-analysis

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Asian pacific Journal of Reproduction 2024年第1期13卷 12-21页

作者： Seyed Sobhan Bahreiny Mojtaba Aghaei Mohammad reza Dabbagh hamid Ghorbani Moslem Javidan reza Mohammadpour Fard Student Research Committee Ahvaz Jundishapur University of Medical SciencesAhvazIran Medical Basic Sciences Research Institute Physiology Research CenterDepartment of PhysiologySchool of MedicineAhvaz Jundishapur University of Medical SciencesAhvazIran Department of Biology Faculty of ScienceShahid Chamran University of AhvazAhvazIran Department of Immunology Faculty of MedicineAhvaz Jundishapur University of Medical SciencesAhvazIran

Objective:To investigate the relationship between ambient sulfur dioxide(SO2)exposure and semen quality ***:A systematic literature search was conducted to identify relevant studies investigating the association between SO2 exposure and semen quality *** search encompassed the timeframe from January 2000 to May 2023 and included electronic databases such as Web of Science,Google Scholar,PubMed,Cochrane,and *** effect estimates with 95%confidence intervals(CI)were calculated using percent changes(PC).The meta-analysis included seven studies with 6711 participants and 15087 semen ***:The results revealed a significant negative association between ambient SO2 exposure and certain semen quality *** particular,SO2 exposure was associated with a significant decrease in progressive motility(PC=0.032;95%CI:-0.063 to-0.001;P=0.044)and sperm concentration(PC=-0.020;95%CI:-0.036 to-0.005;P=0.012).However,no statistically significant associations were observed for total sperm count(PC=-0.038;95%CI:-0.079 to 0.003;P=0.070),seminal fluid volume(PC=-0.009;95%CI:-0.048 to-0.030;P=0.662)and sperm motility(PC=-0.17;95%CI:-0.363 to 0.022;P=0.830).In addition,the results of the subgroup analysis revealed specific variables that were associated with the decrease in relevant sperm ***:This systematic review and meta-analysis provides compelling evidence supporting a consistent negative association between exposure to ambient SO2 and semen quality parameters.

关键词： Semen quality Sulfur dioxide Ambient air pollution Meta-analysis

Experimental and Finite Element Analysis of Corroded High-Pressure Pipeline Repaired by Laminated Composite

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1783-1806页

作者： Seyed Mohammad reza Abtahi Saeid Ansari Sadrabadi Gholam Hosein Rahimi Gaurav Singh hamid Abyar Daniele Amato Luigi Federico Faculty of Mechanical Engineering Tarbiat Modares UniversityTehran***Iran A.Leon Linton Department of Mechanical Robotics and Industrial EngineeringLawrence Technological UniversitySouthfieldMI48075USA Department of Mechanical Engineering Faculty of EngineeringMeybod UniversityYazd***Iran Department of Industrial Engineering University of SalernoVia Giovanni PaoloⅡFiscianoItaly Italian Aerospace Research Center(C.I.R.A.) Via MaioriseCapuaCE81043Italy

Repairs of corroded high-pressure pipelines are essential for fluids transportation under high *** of the methods used in their repairs is the use of layered *** composite used must have the necessary ***,the experiments and analytical solutions presented in this paper are performed according to the relevant standards and codes,including ASME PCC-2,ASME B31.8S,ASME B31.4,ISO 24817 and ASME *** addition,the experimental tests are replicated numerically using the finite element *** the strain gauges at different distances from the defect location,can reduce the nonlinear effects,deformation,and fluctuations due to the high *** direct relationship between the depth of an axial defect and the stress concentration is observed at the inner side edges of the *** reparation reduces the non-linearities related to the sharp variation of the geometry and a more reliable numerical simulation could be performed.

关键词： High-pressure pipeline composite repair ASME PCC-2 ISO 24817

Correlation between critical thinking and emotional intelligence:a national crosssectional study on operating room nursing students in Iran

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Frontiers of Nursing 2024年第1期11卷 99-104页

作者： Armin Fereidouni Esmaeil Teymoori Tayebeh Bahmani hamid reza Sabet Zahra Maleki Mina Gharibi Department of Operating Room Technology Community Based Psychiatric Care Research CenterSchool of Nursing and MidwiferyShiraz University of Medical SciencesShirazIran Department of Operating Room Technology School of Paramedical SciencesAJA University of Medical SciencesTehranIran Department of Operating Room School of Allied Medical ScienceFasa University of Medical SciencesFasaIran Clinical Education Research Center Shiraz University of Medical SciencesShirazIran Medical Journalism Department School of Paramedical SciencesShiraz University of Medical SciencesShirazIran Department of Epidemiology Student Research CommitteeShiraz University of Medical SciencesShirazIran

Objective:According to the World Federation of Medical Education,critical thinking should be part of the training of medical and paramedical *** can improve the quality of care of patients after surgery by having or acquiring this skill in health ***,Emotional intelligence is introduced as an impor tant and effective factor on the professional performance and mental health of healthcare ***,the present study was designed and implemented to determine the relationship between emotional intelligence and critical thinking among operating room nursing students of medical sciences universities in ***:This cross-sectional study was done on 420 operating room students in 10 top medical sciences universities of Iran in *** sampling method in this research was multistage *** data collection instruments included demographic characteristics,Rickett's critical thinking,and Bradberry-Greaves'emotional intelligence *** receiving the ethics code,data collection was done for 2 *** data analysis,descriptive and inferential analyses including independent t-tests,analysis of variance,and Pearson correlation were *** collected data were analyzed by SPSS 18(IBM Corporation,Armonk,New York,United States).P-value<0.05 was considered ***:The mean age of the students participating in this study was 23.02±3.70 years,with women constituting 67.4%of *** results of data analysis indicated that the mean total score of critical thinking and emotional intelligence was 124.10±37.52 and 114.12±43.63,respectively.A direct significant correlation between critical thinking and emotional intelligence(r=0.459,P-value<0.001)and a significant relationship between gender and emotional intelligence(P-value=0.028)were ***:Based on the present study results,educational managers in the Ministry of Health are suggested to consider suitable educational programs for improving critical think

关键词： critical thinking emotional intelligence operating room students operating room nurses

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