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Journal of Thermal Science 2021年第5期30卷 1827-1841页

作者： HAMID mousavi seyed MOSTAFA Tabatabaee Ghomshe ALIMORAD Rashidi MASOUMEH Mirzaei Department of Chemical Engineering Mahshahr BranchIslamic Azad UniversityMahshahrIran Nanotechnology Research Center Research Institute of Petroleum Industry(RIPI)West Blvd.Azadi Sports ComplexP.O.Box 146651998TehranIran

This study presents the use of Silver-Carbon Quantum Dots(Ag-CQD)hybrid nanofluids,prepared by a facile wet chemical method,for heat transfer enhancement of wet cooling towers *** samples were characterized using different analyses,including FT-IR,XRD and *** synthesizing the CQD,it was hybridized with silver nanoparticles and dispersed in water,using ultrasonic *** viscosity and density of the prepared nanofluid were investigated as a function of temperature and nanoparticles concentration,which demonstrated that there were no noticeable changes at lower particles ***,thermal conductivity and convective heat transfer coefficient were measured to evaluate the heat transfer enhancement of the *** 45℃ and 0.5 wt%,the most significant thermal conductivity improvement compared to the base fluid was 24%;and 28%enhancement of the heat transfer coefficient was obtained at Reynolds number of *** nanofluid performance was evaluated in a wet cooling tower for investigating the efficiency and water consumption *** results indicated that the efficiency of the cooling tower,by applying Ag-CQD nanofluid,enhanced from 23.72%to 28.23%;consequently,the amount of the consumed water decreased from 80.76 mL·min^(−1)to 69.67 mL·min^(−1).The results proved that the prepared nanofluid is a successful and promising candidate to enhance heat transfer.

关键词： nanofluid carbon quantum dot silver hybrid heat transfer wet cooling tower

Formation mechanism of Al2O3/MoS2 nanocomposite coating by plasma electrolytic oxidation(PEO)

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Plasma Science and Technology 2020年第6期22卷 144-155页

作者： Babak GHORBANIAN Mohammad TAJALLY seyed Mohammad mousavi KHOIE Hossein TAVAKOLI Faculty of Materials and Metallurgical Engineering Semnan UniversityPO Box 35131-19111SemnanIran Faculty of Mining and Metallurgical Engineering Amirkabir University of TechnologyPO Box 15875-4413 TehranIran

In this study,an Al2O3/MoS2 nanocomposite coating was created on an aluminum 1050 substrate using the plasma electrolytic oxidation *** zeta potential measurements showed that small MoS2 particles have negative potential and move toward the anode *** nanoparticles of MoS2 were found to have a zeta potential of-25 mV,which prevents suspension in the ***,to produce an Al2O3/MoS2 nanocomposite,one has to use the microparticles of *** X-ray diffraction analyses showed that the produced coatings containedα-Al2O3,γ-Al2O3,and MoS2,and that the size of MoS2 particles can be reduced to 30 *** was observed that prolonged suspension in the electrolyte results in an enhanced formation of an Al2O3/MoS2 *** the results,it was hypothesized that the mechanism of the formation of the Al2O3/MoS2 nanocomposite coating on the aluminum 1050 substrate is based on electrical energy discharge.

关键词： plasma electrolytic oxidation corrosion Al2O3/MoS2 nanocomposite tribology

The Roman k-domatic Number of a Graph

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Acta Mathematica Sinica,English Series 2011年第10期27卷 1899-1906页

作者： seyed mahmoud SHEIKHOLESLAMI Lutz VOLKMANN Department of Mathematics Azarbaijan University of Tarbiat MoaUem Tabriz 53714-161 L R. Iran and School of Mathematics Institute for Research in Fundamental Sciences ( IPM) Lehrstuhl H fiir Mathematik RWTH Aachen University 52056 Aachen Germany

Let k be a positive integer. A Roman k-dominating function on a graph G is a labeling f ： V（G） → {0, 1, 2} such that every vertex with label 0 has at least k neighbors with label 2. A set {f1, f2,..., fd} of distinct Roman k-dominating functions on G with the property that ∑di=1 fi（v） ≤ 2 for each v C V（G）, is called a Roman k-dominating family （of functions） on G. The maximum number of functions in a Roman k-dominating family on G is the Roman k-domatic number of G, denoted by dkR（G）. Note that the Roman 1-domatic number dlR（G） is the usual Roman domatic number dR（G）. In this paper we initiate the study of the Roman k-domatic number in graphs and we present sharp bounds for dkR（G）. In addition, we determine the Roman k-domatic number of some graphs. Some of our results extend those given by Sheikholeslami and Volkmann in 2010 for the Roman domatic number.

关键词： Roman domination number Roman domatic number Roman k-domination number Ro- man k-domatic number

Irrigation effects on diameter growth of 2-year-old Paulownia tomentosa saplings

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Journal of Forestry Research 2015年第1期26卷 153-157页

作者： Javad Eshaghi Rad seyed Rostam mousavi Mirkala Department of Forestry Faculty of Natural ResourcesUrmia University

Species of Paulownia are fast-growing trees that are planted in many countries in green spaces and agroforestry systems. We studied the influence of irrigation on the diameter growth of 2-year-old Paulownia tomentosa saplings planted in 3 m 9 3 m grids at Nazlou Campus of Urmia University, Iran. Completely randomized experimental design was used with four irrigation amount, viz.10, 15, 20 and 25 L, and three irrigation intervals, viz. 3-and 6-days, in 8 replications. During the growth season, we measured collar diameters of all saplings at the end of each month. Diameter growth declined with reduced irrigation amount and increased irrigation interval. The lowest average diameter growth（9 mm） was recorded for 10 L water at 6-day intervals and maximum average diameter growth（28.7 mm） was recorded for 25 L volume at 3-day intervals. The latter treatment resulted in significantly greater diameter growth than any other treatment（except20 L at 3-day intervals）. More than 80 % of diameter growth was achieved in the first 3 months. Therefore, it is essential to irrigate with 25 L of water at 3-day intervals during the first three growth months to achieve maximum diameter growth for 2-year-old P. tomentosa saplings.

关键词： Paulownia tomentosa Diameter growth Irrigation interval Iran

Unraveling a Driven Damped Harmonic Oscillator through Entangled State Representation

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Chinese Physics Letters 2013年第11期30卷 22-24页

作者： seyed mahmoud Ashrafi Mohammad Reza Bazrafkan Department of Physics Faculty of ScienceI.K.I.UniversityQazvinIran

Employing the thermo-entangled state representation,the common eigenstates of relative position and the total momentum of a two-mode system,we solve the master equation of a damped harmonic oscillator driven by a time... 详细信息

关键词： field momentum harmonic

Exploring the relationship between Hashimoto's thyroiditis and male fertility:A meta-analytic and meta-regression perspective on hormonal and seminal factors

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Asian pacific Journal of Reproduction 2024年第4期13卷 147-159页

作者： seyed Sobhan Bahreiny Mojtaba Aghaei Mahdi Amraei Mohammad Reza Dabbagh 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 Thalassemia&Hemoglobinopathy Research Center Health Research InstituteAhvaz Jundishapur University of Medical SciencesAhvazIran USERN Office Ahvaz Jundishapur University of Medical SciencesAhvazIran Department of Biology Faculty of ScienceShahid Chamran University of AhvazAhvazIran

Objective:To explore the relationship between Hashimoto's autoimmune hypothyroidism(HT)and male fertility,focusing on hormonal and seminal ***:A systematic literature search was conducted across databases such as PubMed,Web of Science,EMBASE,Scopus,Cochrane,and Google Scholar,covering studies published from January 2000 to March *** investigating the impact of HT on semen quality parameters and reproductive hormones were *** effect estimates were calculated using standard mean difference(SMD)and 95%confidence intervals(CI).Results:A total of 8 studies with 8965 participants were *** significantly affected semen quality and reproductive hormone ***,there was a notable decrease in progressive morphology(SMD=-0.78;95%CI:-1.40 to-0.17;P=0.01)and sperm motility(SMD=-1.151;95%CI:-1.876 to-0.425;P=0.002).In addition,there were no significant changes in reproductive hormones,although there were elevated levels of luteinizing hormone(SMD=0.437;95%CI:0.000 to 0.874;P=0.050)and follicle-stimulating hormone(SMD=0.293;95%CI:-0.171 to 0.758;P=0.216),with a slight impact on testosterone levels(SMD=-1.143;95%CI:-2.487 to 0.200;P=0.095).Conclusions:This systematic review and meta-analysis provides robust evidence of the detrimental effects of HT on semen quality and reproductive hormones,underscoring the necessity for thorough evaluation and management of thyroid function in male infertility assessments.

关键词： Hashimoto thyroiditis Male fertility Semen quality Reproductive hormones Meta-analysis Meta-regression

Optimum placement and characteristics of velocity-dependent dampers under seismic excitation

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Earthquake Engineering and Engineering Vibration 2012年第3期11卷 403-414页

作者： seyed Amin mousavi Amir K.Ghorbani-Tanha R&D Department Sabok Sazan Sarie Engineering Company School of Civil Engineering College of EngineeringUniversity of Tehran

In this study, through novel drift-based equations of motion in the frequency domain, optimum placement and characteristics of linear velocity-dependent dampers are investigated. In this study, the sum of the square of the absolute values of transfer matrix elements for interstory drifts is considered as the optimization index. Optimum placement and characteristics of dampers are simultaneously obtained by minimizing the optimization index through an incremental procedure. In each step of the procedure, a predefined value is considered as the damper characteristic. The optimum story for this increment is selected such that it leads to a minimum value for the optimization index. The procedure is repeated for the next increments until the optimization index meets its target value, which is obtained according to the desired damping ratio for the overall structure. In other words, the desired overall damping ratio is the input to the proposed procedure, and the optimal placement and characteristics of the dampers are its output. It is observed that the optimal placement of a velocitydependent damper depends on the damping coefficient of the added damper, frequency of the excitation, and distribution of the mass, stiffness, and inherent damping of the main structure.

关键词： passive control velocity-dependent damper optimum placement optimum damping transfer matrix storydamping coefficient

Microstructural analyses of aluminum–magnesium–silicon alloys welded by pulsed Nd: YAG laser welding

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International Journal of Minerals,Metallurgy and Materials 2020年第5期27卷 660-668页

作者： Hossain Ebrahimzadeh Hassan Farhangi seyed Ali Asghar Akbari mousavi Arman Ghahramani School of Metallurgy and Materials Engineering College of EngineeringUniversity of TehranTehran 11155-4563Iran

Revealing grains and very fine dendrites in a solidified weld metal of aluminum–magnesium–silicon alloys is difficult and thus,there is no evidence to validate the micro-and meso-scale physical models for hot cracks. In this research, the effect of preheating on the microstructure and hot crack creation in the pulsed laser welding of AA 6061 was investigated by an optical microscope and field emission electron microscopy. Etching was carried out in the gas phase using fresh Keller’s reagent for 600 s. The results showed that the grain size of the weld metal was proportional to the grain size of the base metal and was independent of the preheating temperature. Hot cracks passed the grain boundaries of the weld and the base metal. Lower solidification rates in the preheated samples led to coarser arm spacing;therefore, a lower cooling rate. Despite the results predicted by the micro and meso-scale models, lower cooling rates resulted in increased hot cracks. The cracks could grow in the weld metal after solidification;therefore, hot cracks were larger than predicted by the hot crack prediction models.

关键词： etching technique laser welding inter-dendritic spacing grain size aluminum–magnesium–silicon alloys hot crack formation model

Probiotic microorganisms affect the reproductive and nervous systems of male rats treated with acrylamide

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Asian pacific Journal of Reproduction 2024年第4期13卷 178-186页

作者： seyedhossein Hekmatimoghaddam Maryam Yadegari Fateme Zare Fatemeh Zakizadeh seyed Mohammad Seifati Hematology and Oncology Research Center Shahid Sadoughi University of Medical SciencesYazdIran Department of Laboratory Sciences School of ParamedicineShahid Sadoughi University of Medical SciencesYazdIran Neuroendocrine Research Center Shahid Sadoughi University of Medical SciencesYazdIran Department of Anatomy and Cell Biology Faculty of MedicineShahid Sadoughi University of Medical SciencesYazdIran Reproductive Immunology Research Center Shahid Sadoughi University of Medical SciencesYazdIran

Objective:To evaluate the protective effects of probiotic microorganisms on the reproductive and nervous systems of male rats treated with ***:Thirty-two rats were randomly divided into 4 groups and received normal saline through gavage(control),acrylamide 20 mg/kg body weight,acrylamide plus probiotic microorganisms(Lactobacillus acidophilus,Lactobacillus casei,Lactobacillus bulgaricus,Lactobacillus rhamnosus,Bifidobacterium breve,Bifidobacterium infantis,Streptococcus thermophilus and fructooligosaccharides,all mixed in sachets)20 or 200 mg/kg body weight,*** 30 days,the testis,prostate,seminal vesicle and cerebellum were removed,fixed and stained with hematoxylin-eosin(H&E).The Johnsen score was used to classify ***'s principle method was used to evaluate the total volume(in mm3)of the *** number of each intratubular cell type as well as intertubular Leydig cells in whole samples was measured using the physical dissector counting *** analysis and the grids were used to determine the volume of cerebellar layers as well as the Purkinje cell ***:The testis weight decreased significantly in the acrylamide-treated group compared to the other groups(P<0.001).The number of spermatogonia,spermatocytes,spermatids and Leydig cells in the acrylamide-treated group were significantly less compared to the control group(P<0.05),while they were increased significantly in the acrylamide+200 mg/kg probiotic group(P<0.05;P<0.01).The mean Johnsen score in the acrylamide-treated group was lower than in the control group(P<0.001).Acrylamide-induced changes including congestion,vacuolization in the secretory epithelial cells,and epithelial rupture were observed in the prostate and seminal *** volumes of cerebellar layers were decreased in the acrylamide group compared to the control group while recovered in both probiotic treated ***:Probiotic microorganisms alleviate acryl

关键词： Acrylamide Cerebellum Microorganisms Probiotics Prostate Rats Testis

Geometrically Nonlinear Analysis of Structures Using Various Higher Order Solution Methods: A Comparative Analysis for Large Deformation

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Computer Modeling in Engineering & Sciences 2019年第12期121卷 877-907页

作者： Ali Maghami Farzad Shahabian seyed mahmoud Hosseini Civil Engineering Department Faculty of EngineeringFerdowsi University of MashhadMashhadIran Industrial Engineering Department Faculty of EngineeringFerdowsi University of MashhadMashhadIran

The suitability of six higher order root solvers is examined for solving the nonlinear equilibrium equations in large deformation analysis of *** applied methods have a better convergence rate than the quadratic Newton-Raphson *** six methods do not require higher order derivatives to achieve a higher convergence *** algorithms are developed to use the higher order methods in place of the Newton-Raphson method to solve the nonlinear equilibrium equations in geometrically nonlinear analysis of *** higher order methods are applied to both continuum and discrete problems(spherical shell and dome truss).The computational cost and the sensitivity of the higher order solution methods and the Newton-Raphson method with respect to the load increment size are comparatively *** numerical results reveal that the higher order methods require a lower number of iterations that the Newton-Raphson method to *** is also shown that these methods are less sensitive to the variation of the load increment *** it is indicated in numerical results,the average residual reduces in a lower number of iterations by the application of the higher order methods in the nonlinear analysis of structures.

关键词： Geometrically nonlinear analysis higher order methods predictor-corrector algorithms convergence rate sensitivity to the increment size