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Journal of Rare Earths 2014年第1期32卷 57-77页

作者： Mohammadreza Daroonparvar Muhamad Azizi Mat Yajid Noordin Mohd Yusof hamid reza Bakhsheshi-Rad Z.Valefi Esah Hamzah Department of Materials Manufacturing and Industrial Engineering Faculty of Mechanical Engineering Universiti Teknologi Malaysia School of Metallurgy and Materials College of Engineering University of Tehran

Bi-layered thermally grown oxide （TGO） layer plays a major role in the spallation of Y2O3 stabilized ZrO2 （YSZ） layer form the bond coat in the thermal barrier coating （TBC） systems during oxidation. On the other hand, bi-layered TGO formation and growth in the TBC systems with nanostructured YSZ have not been deeply investigated during cyclic oxidation. Hence, Inconel 738/NiCrAlY/normal YSZ and Inconel 738/NiCrAlY/nano YSZ systems were pre-oxidized at 1000 °C and then subjected to cyclic oxidation at 1150 °C. According to microstructural observations, nanostructured YSZ layer over the bond coat should have less mi-cro-cracks and pinholes, due to the compactness of the nanostructure and the presence of nano zones that resulted in lower O infiltration into the nanothermal barrier coating system, formation of thinner and nearly continuous mono-layered thermally grown oxide on the bond coat during pre-oxidation, lower spinels formation at the Al2O3/YSZ interface and finally, reduction of bi-layered thermally grown oxide thickness during cyclic oxidation. It was found that pre-heat treatment and particularly coating microstructure could influence microstructural evolution （bi-layered TGO thickness） and durability of thermal barrier coating systems during cyclic oxidation.

关键词： spinels oxidation three stages TGO growth pre-heat treatment rare earths

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

Experimental investigation of wettability alteration on residual oil saturation using nonionic surfactants: Capillary pressure measurement

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Petroleum 2015年第4期1卷 289-299页

作者： Masoud Amirpour Seyed reza Shadizadeh hamid Esfandyari Saeid Ahmadi Department of Petroleum Engineering Abadan Faculty of Petroleum EngineeringPetroleum University of TechnologyAbadanIran Department of Petroleum Engineering Tehran UniversityTehranIran

Introducing the novel technique for enhancing oil recovery from available petroleum reservoirs is one of the important issues in future energy *** of all operative factors,wettability may be the foremost parameter affecting residual oil saturation in all stage of oil *** wettability alteration is one of the methods which enhance oil recovery from the petroleum ***,the studies which focused on this subject were more than the past and many contributions have been made on this *** main objective of the current study is experimentally investigation of the two nonionic surfactants effects on altering wettability of reservoir *** of this work is to change the wettability to preferentially the water-wet *** reducing the residual oil saturation(Sor)is the other purpose of this *** wettability alteration of reservoir rock is measured by two main quantitative methods namely contact angle and the USBM *** of this study showed that surfactant flooding is more effective in oil-wet rocks to change their wettability and consequently reducing Sor to a low ***(Zizyphus Spina Christi)is low priced,absolutely natural,and abundantly accessible in the Middle East and Central *** on the results,this material can be used as a chemical surfactant in field for enhancing oil recovery.

关键词： Wettability alteration Residual oil saturation Nonionic surfactant USBM method Contact angle

Improving shipboard electronics cooling system by optimizing the heat sinks configuration

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Journal of Ocean Engineering and Science 2022年第5期7卷 498-508页

作者： hamid Maleki Mohammad reza Safaei Arturo S.Leon Taseer Muhammad Truong Khang Nguyen Department of Mechanical Engineering Isfahan University of TechnologyIsfahan 84156-83111Iran Department of Mechanical Engineering Florida International UniversityMiamiFL 33174USA Department of Medical Research China Medical University HospitalChina Medical UniversityTaichungTaiwan Mechanical Engineering Department Faculty of EngineeringKing Abdulaziz UniversityJeddahSaudi Arabia Department of Civil and Environmental Engineering Florida International UniversityMiamiFL 33174USA Department of Mathematics College of SciencesKing Khalid UniversityAbha 61413Saudi Arabia Division of Computational Physics Institute for Computational ScienceTon Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Electrical and Electronics Engineering Ton Duc Thang UniversityHo Chi Minh CityVietnam

With the increase of high-power electrical components in modern ships,especially fully electric ships with electric propulsion drive(EPD),the cooling of EPD electrical components has become particularly *** optimal configurations for heat sinks with high thermal efficiency plays an essential role in this regard.A new technique for improving the efficiency of heat sinks is the utilization of perforated *** study examined the effects of perforation geometry(shape and size)on laminar airflow flow and heat transfer characteristics over a perforated plate-fin heat ***-dimensional simulations were conducted using the finite-volume scheme based on the SIMPLE *** this research,the effects of perforation shape and size on various parameters,e.g.,total drag force,average Nusselt number,perforated fin efficiency(PFE),heat transfer performance enhancement(HTPE),and fin optimization factor(η)were *** results confirmed that at a specific heat transfer surface area for perforated fins,the highest efficiency is achieved by circular *** contrast,the square perforations due to geometric similarity to rectangular fins could reach the maximum ***,fins with square perforations could achieve the most optimal ***,results showed that for a constant perforations size,change in perforations shape improves HTPE,PFE,andηby more than 40%,45%,and 110%,***,by modifying perforations size for a specified shape,an increment of more than 35%,40%,and 150%is observed in HTPE,PFE,andη,respectively.

关键词： Forced convection Laminar flow Perforated fin Plate-fin heat sink Nusselt number

Influences of gap size and cyclic-thermal-shock treatment on mechanical properties of TLP bonded IN-738LC superalloy

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Transactions of Nonferrous Metals Society of China 2018年第5期28卷 920-930页

作者： Vahid MALEKI hamid OMIDVAR Mohammad-reza RAHIMIPOUR Department of Mining and Metallurgical Engineering Amirkabir University of Technology (Tehran Polytechnic) Department of Ceramic Materials and Energy Research Center

Influences of gap size and cyclic-thermal-shock treatment on the mechanical properties of transient liquid phase（TLP） bonded IN-738 LC superalloy were investigated. For this purpose, TLP bonding of IN-738 LC superalloy was carried out in a vacuum furnace using powdered AMS 4777 as the filler metal. The results showed that isothermal solidified zone（ISZ） consisted of Ni solid-solution and the distribution of alloying elements was homogeneous. High hardness of HV 409 and high shear strength of 506 MPa were observed in 40 μm gap sample. Alloying elements formed γ′ precipitates and the solid-solution in the ISZ. Hardness and shear strength of bonds were reduced with increasing the gap size（in range of 40-120 μm）. The fractured surfaces of complete isothermal solidified bonds showed dimpled rupture, but athermal solidified bonds showed cleavage fracture surface. 10, 20, 30 and 40 thermal-shock cycles were applied to 80 μm gap samples, respectively. The shear strength of the bond was measured to be 268 MPa after the 40 th thermal-shock cycle. The sample with gap size of 80 μm was failed due to crack nucleation on faying surface at 45 th thermal-shock cycle. The amount of the produced brittleness due to quenching the samples in water bath was attributed to the number of thermal-shock cycles.

关键词： IN-738 superalloy TLP bonding mechanical properties cyclic-thermal-shock treatment shear strength

Numerical analysis on forced convection enhancement in an annulus using porous ribs and nanoparticle addition to base fluid

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Journal of Central South University 2019年第5期26卷 1089-1098页

作者： Majid SIAVASHI hamid reza TALESH BAHRAMI Ehsan AMINIAN hamid SAFFARI School of Mechanical Engineering Iran University of Science and Technology

Miniaturization of electronic equipment has forced researchers to devise more effective methods for dissipating the generated heat in these *** this study,two methods,including porous media inserting and adding nanoparticles to the base fluid,are used to improve heat transfer in an annulus heated on both *** study porous media insert,porous ribs are used on the outer and inner walls *** results show that when porous ribs are placed on the outer wall,although the heat transfer enhances,the pressure drop increment is so considerable that performance number (the ratio of heat transfer enhancement pressure increment,PN) is less than unity for all porous rib heights and porous media permeabilities that are *** the other hand,the PN of cases where porous ribs were placed on the inner wall depends on the Darcy number (Da).For example,for ribs with Da=0.1 and Da=0.0001,the maximum performance number,PN=4,occurs at the porous ribs height to hydraulic diameter ratios H/Dh=1 and H/Dh=*** these conditions,heat transfer is enhanced by two orders of *** is found that adding 5% nanoparticles to the base fluid in the two aforementioned cases improves the Nusselt number and PN by 10%–40%.

关键词： nanofluid porous media annulus heat transfer enhancement internal flow

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

Distribution changes of woody plants in Western Iran as monitored by remote sensing and geographical information system:a case study of Zagros forest

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Journal of Forestry Research 2017年第1期28卷 145-153页

作者： Mansour Karkon Varnosfaderani Rasoul Kharazmi Aliakbar Nazari Samani Mohammad reza Rahdari Seid hamid Matinkhah Nasrollah Aslinezhad State University of Land Use Planning MoscowRussianFederation St.Petersburg State University PetersburgRussianFederation Faculty of Natural Resource University of TehranKarajIran Isfahan University of Technology IsfahanIran Faculty of Water and Soil Zabol UniversityZabolIran

The status of woody plants in dry-land systems is a fundamental determinant of key ecosystem processes. Monitoring of this status plays an important role in understanding the dynamics of woody plants in arid and semi-arid ecosystems. The present study determined the dynamism of the Zagros forests in Iran using Remote Sensing and Geographic Information System techniques and statistical science. The results show that the density of trees varied from 10 to 53 % according to the physio- graphic and climatic conditions of semi-arid regions. The best and lowest correlation between vegetation indices and forest density were obtained for the global environmental monitoring index （GEMI; R2 = 0.94） and soil adjust vegetation index （R2 = 0.81）, respectively. GEMI is used to monitor land use changes over a 10-year period. Results show that 2720 ha2 of forest have been destroyed by human interference and tillage on steep slopes during this period which also resulted in the loss of the fertile soil layer. GEMI determined the areas with a biomass of trees and could normally separate border regions with low bio- mass density of trees from regions without canopy cover. The results revealed that assessment of forest and vegetation cover in arid and semi-arid arduous forest regions using satellite digital numbers and ordinary sampling is subject to uncertainty. A stratified grouping procedure should be established to increase the accuracy of assessment.

关键词： Monitoring Woody plants Vegetation index RS GIS Zagros forest Iran

Astragalus adscendens extract shows antidiabetic effects through controlling oxidative stress,inflammation and apoptosis in streptozotocin-induced diabetic rats

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Asian Pacific Journal of Tropical Biomedicine 2023年第6期13卷 242-249页

作者： Yosra Raziani Kimia Karami hamid reza Mohammadi Hossein Mahmoudvand Mohammad Nabi Moradi Javad Ghasemian Yadegari Nursing Department Al-Mustaqbal University College51001 HillahBabylonIraq Razi Herbal Medicines Research Center Lorestan University of Medical SciencesKhorramabadIran Molecular and Cellular Laboratory School of Allied MedicineLorestan University of Medical SciencesKhorramabadIran

Objective:To assess the effect of oral treatment of methanolic extract of the aerial parts of Astragalus adscendens in streptozotocin-induced diabetic ***:In order to induce diabetes,rats intraperitoneally received streptozotocin at 65 mg/*** adult male Wistar rats were allocated into six groups(10 rats per each)including the healthy control group,the diabetic group as well as the diabetic group treated with Astragalus adscendens methanolic extract at 50,100,and 200 mg/kg per day or glibenclamide(0.6 mg/kg/day)for 28 *** effects of Astragalus adscendens methanolic extract on the levels of glucose,insulin,alanine aminotransferase,alkaline phosphatase,aspartate aminotransferase,bilirubin,creatinine,urea,uric acid,total protein,albumin,triglyceride,cholesterol,α-amylase,oxidant/antioxidant enzymes,and inflammatory cytokines were *** time-PCR was also used for measuring the gene expression of caspase-3,Bcl2,and ***:The levels of glucose,cholesterol,triglyceride,creatinine,urea,uric acid,alanine aminotransferase,aspartate aminotransferase,alkaline phosphatase,bilirubin,and malondialdehyde considerably declined(P<0.001)in diabetic rats after treatment with Astragalus adscendens methanolic extract especially at a dose of 200 mg/*** addition,treatment with Astragalus adscendens methanolic extract noticeably increased the level of insulin,total protein,and albumin as well as improved the activities of catalase,glutathione peroxidase,and superoxide dismutase,as well as the expression levels of TNF-α,IL-1β,caspase-3,Bcl2 and Bax(P<0.001)compared to the diabetic control *** extract also inhibitedα-amylase in a dose-dependent manner with an IC_(50)value of 19.6μg/***:Astragalus adscendens methanolic extract shows potent antidiabetic,anti-inflammatory,anti-apoptotic,and antioxidant effects in diabetic ***,more studies are needed to verify the underlying mechanism of the effect of this plant extract and test its effica

关键词： Herbal medicines Astragalus adscendens Diabetes Antioxidant Antidiabetes Streptozotocin Antiinflammation

Effect of canopy gap size and ecological factors on species diversity and beech seedlings in managed beech stands in Hyrcanian forests

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Journal of Forestry Research 2012年第2期23卷 217-222页

作者： Kambiz Abrari Vajari hamid Jalilvand Mohammad reza Pourmajidian Kambiz Espahbodi Alireza Moshki Faculty of Natural Resources Sari Agriculture Sciences and Natural Resources University Iran Research Center in Agricultural and Natural Resources of Mazandaran Province Sari Iran Soil science of temperate and boreal ecosystems Institute Faculty of forest science and forest ecology Georg-August University of Goettingen Germany

We studied the species diversity of the herb layer and ecological factors in harvest-created gaps in beech stands under a single-tree selection system in Northern Iran. To determine diversity, the number of beech seedlings, and other ecological factors, 16 gaps were selected and subplots of 5 m2 were positioned at the centre and at the cardinal points of each gap. Species richness and Simpson diversity index increased with increasing gap area as did numbers of seedlings. With increasing humus layer thickness, species richness declined but the Hill evenness index increased. Species richness increased with increasing light availability. There was no relationship between crown radii of beech trees and diversity indices. Correlations between environmental factors and numbers of individuals of some species in the herb layer were not significant except in a few cases. The results help explain the effects of man-made gaps on the dynamics of managed beech stands and this benefits evaluation of silvicultural operating plans.

关键词： beech gap herbaceous species diversity Hyrcanian for- ests