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International Journal of Minerals,Metallurgy and Materials 2020年第6期27卷 809-817页

作者： Majid hosseini mohammad hossein Paydar Department of Materials Science and Engineering School of EngineeringShiraz UniversityShiraz 71964-84334Iran

Despite the existence of conventional methods for recycling chips,solid-state techniques have become popular,whereby waste metals are directly recycled into consolidated products with the desired shapes and *** investigated the feasibility of recycling phosphor bronze chips through a hot extrusion process using aluminum powder as a metal binder for the fabrication of a metal-fiber-reinforced aluminum matrix *** do so,mixtures containing 20 vol%–50 vol%of chips were prepared,cold-compacted,and *** quality of the consolidated samples was evaluated by determining the density of the fabricated composites and studying their *** addition,we performed tensile and hardness tests to evaluate the mechanical properties of the fabricated *** also analyzed the fracture surfaces of the samples to study the fracture mechanism as a function of the volume fraction of phosphor bronze chips in the fabricated *** results indicated that the most effective consolidation occurred in the sample containing 20 vol%of chips extruded at 465℃in which the chips serve as ideal fibers for improving the mechanical properties,especially the ultimate tensile strength,in comparison with those of Al matrixes that contain no chips but are produced under the same conditions.

关键词： recycling hot extrusion metal–metal composite phosphor bronze chips aluminum powder

Finding buckling points for nonlinear structures by dynamic relaxation scheme

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Frontiers of Structural and Civil Engineering 2020年第1期14卷 23-61页

作者： mohammad REZAIEE-PAJAND hossein ESTIRI Civil Engineering Department Ferdowsi University of MashhadMashhad 91775-1111Iran

Dynamic Relaxation Method(DRM)is an explicit approach for solving the simultaneous systems of *** this tactic,the fictitious mass and damping are added to the static governing equations,and an artificial dynamic system is *** using DRM for nonlinear analysis,the structural static equilibrium path is *** outcome is extremely valuable,since it leads to the behavior of *** the finding related to the structural static path are the critical and buckling points for nonlinear *** this paper,a new way for calculating the load factor is proposed by setting the external work *** the dynamic relaxation scheme with external work technique has not been formulated so *** all incremental-iterative methods,the load factor increment sign should be determinated by extra *** sign leads to increase or decrease of the load *** is worth emphasizing that sign of the load factor increment changes at the load limit ***,the sign determinations are required in the common work control *** disadvantages are eliminated in the proposed *** fact,the suggested load factor depends only on the Dynamic Relaxation(DR)fictitious ***,all DR calculations are performed via vector ***,the load factor is calculated only by one formula,and it has the same relation in the all solution *** contrast to the arc length techniques,which requires the sign determined,the proposed scheme does not need any sign *** is shown that author’s technique is quicker than the other dynamic relaxation *** prove the capability and efficiency of the presented scheme,several numerical tests are *** results indicate that the suggested approach can trace the complex structural static paths,even in the snap-back and snap-through parts.

关键词： load factor external work dynamic relaxation static equilibrium path large displacement

The thermal analysis of the heat dissipation system of the charging module integrated with ultra-thin heat pipes

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Energy and Built Environment 2023年第5期4卷 506-515页

作者： Tingzhen Ming Xiwang Liao Tianhao Shi Kui Yin Zhiyi Wang mohammad hossein Ahmadi Yongjia Wu School of Civil Engineering and Architecture Wuhan University of TechnologyWuhan 430070China China Constuction Third Bureau First Engineering Co.LTD.Wuhan 430040 China Faculty of Mechanical Engineering Shahrood University of TechnologyShahroodIran

Electric vehicles(EV)played an important role fighting greenhouse gas emissions that contributed to global *** construction of the charging pile,which was called as the"gas station"of EV,developed *** charging speed of the charging piles was shorted rapidly,which was a challenge for the heat dissipation system of the charging *** order to reduce the operation temperature of the charging pile,this paper proposed a fin and ultra-thin heat pipes(UTHPs)hybrid heat dissipation system for the direct-current(DC)charging *** L-shaped ultra-thin flattened heat pipe with ultra-high thermal conductivity was adopted to reduce the spreading thermal *** software was used to simulate the temperature and flow profiles of the new *** various factors that affected the heat dissipation performance of the system were *** results showed that the system had excellent heat dissipation capacity and achieved good temperature *** than solely relied on the fans,this new design efficiently dissipated heat with a lower fan load and less energy consumption.

关键词： ICEPAK simulation Charging pile heat transfer Ultra-thin heat pipe Chip cooling

Novel technique of penetrating keratoplasty in high-risk grafts with significant corneal neovascularization

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International Journal of Ophthalmology(English edition) 2022年第9期15卷 1554-1556页

作者： mohammad Soleimani Nader mohammadi Mansoor Shahriari Morteza Karimi Ahmed Alshaheeb Atefeh Khalili mohammad hossein Zamani Kasra Cheraqpour Eye Research Center Farabi Eye HospitalTehran University of Medical SciencesTehran ***Iran Imam hossein Medical Center Shahid Beheshti University of Medical SciencesTehran ***Iran

Dear Editor,We write to introduce a novel technique of penetrating keratoplasty(PK)with lower risk of graft rejection in high-risk *** transplantation may be required in a variety of conditions such as keratoconus,pse... 详细信息

关键词： such keratoplasty corneal

A simulation study on p-doping level of polymer host material in P3HT:PCBM bulk heterojunction solar cells

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Chinese Physics B 2017年第4期26卷 508-512页

作者： hossein Movla mohammad Babazadeh Azar Aytash Co. Technology IncubatorUniversity of TabrizTabrizIran

In this study,we investigate the influence of doping on the charge transfer and device characteristics parameters in the bulk heterojunction solar cells based on poly（3-hexylthiophene）（P3HT） and a methanofuUerene derivative（PCBM）.Organic semiconductors are also known to be not pure and they have defects and impurities,some of them are being charged and act as p-type or n-type *** of the solar cell characteristics parameters versus the p-doping level have been done at three different n-dopings（N_d） that consist of 5 × 10^（17） cm^（-3）,10^（18） cm^（-3）,and 5 × 10^（18） cm^（-3）.We perform the analysis of the doping concentration through the drift-diffusion model,and calculate the current and voltage doping *** find that at three different n-dopant levels,optimum p-type doping is about N_p = 6 × 10^（18） cm^（-3）.Simulation results have shown that by increasing doping level,V_（oc） monotonically increases by *** efficiency reaches its maximum at somewhat higher doping as FF has its peak at N_p = 3 × 10^（18） cm^（-3）.Moreover,this paper demonstrates that the optimum value for the p-doping is about N_p = 6 × 10^（18） cm^（-3） and optimum value for n-dopant is N_d = 10^（18） cm^（-3）,*** simulated results confirm that doping considerably affects the performance of organic solar cells.

关键词： organic photovoltaics charge transport doping finite difference method

Estimating oak forest parameters in the western mountains of Iran using satellite-based vegetation indices

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Journal of Forestry Research 2020年第2期31卷 541-552页

作者： Adel Nouri Bahman Kiani mohammad hossein Hakimi mohammad hossein Mokhtari Department of Forest Sciences Faculty of Natural ResourcesYazd UniversityYazdIslamic Republic of Iran Department of Desert Management Faculty of Natural ResourcesYazd UniversityYazdIslamic Republic of Iran

Remote sensing is an important tool for studying and modeling forest *** indices obtained from Landsat-8 remotely sensed data were used to estimate the forest parameters in the western mountains of *** sample points were selected on the map of Bayangan County,Kermanshah province,*** each point,a cluster of five rectangular plots of 8100 m2 and 200 m apart was *** clusters were primarily sampled to determine the variance of the forest *** coefficient of variation was used as a criterion for sample *** density,canopy cover and basal area per hectare were calculated for each *** indices were extracted fromthe Landsat-8 images for each *** linear and nonlinear regressions were conducted to develop the *** models were validated using an independent data *** of model parameters was statistically *** results showed that Normalized difference vegetation index(NDVI)and Transformed normalized difference vegetation index(TNDVI)followed by Simple ratio vegetation index(SRVI)were the best predictors,explaining up to 91%of the variations with high *** NDVI,Soil adjusted vegetation index 2(SAVI2)and SRVI,the cubic model was more appropriate than the linear model for predicting the forest *** this model,the R-square value increased while NRMSE decreased *** Infrared percentage vegetation index(IPVI),the quadratic model was better,but,for other vegetation indices,nonlinear models were not superior to linear ***,it can be concluded that Landsat-8 imagery is suitable for predicting forest parameters in the oak forests of western *** course,large plots must be selected,and pre-classification is necessary to gain accurate and precise estimations.

关键词： Basal area Canopy cover Density Landsat-8 Modeling

Thermal Analysis Simulation of Germanium Zone Refining Process Assuming a Constant Radio-Frequency Heating Source

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Chinese Physics Letters 2016年第5期33卷 123-126页

作者： Mahdi Ezheiyan hossein Sadeghi mohammad-hossein Tavakoli Department of Physics Malek-Ashtar University of Technology Department of Physics Bu-Ali Sina University

Three-dimensional thermal a nalysis simulation of a horizontal zone refining system is conducted for germanimn semiconductor materials. The considered geometry includes a g＇ral）hite boat filled with germanium placed in a cylindrical quartz tube. A flow of Ar and H2 gas mixture is purged througll the tube. A narrow section of the, boat is assmned to be exposed to a constant heat rate produced b v an rf coil located outside the quartz tube. The results of this analysis provide essential information about various parameters such as the shape of tile molten zone, required power and temperature gradient in the system.

关键词： of on Thermal Analysis Simulation of Germanium Zone Refining Process Assuming a Constant Radio-Frequency Heating Source in is for

A functorial approach to categorical resolutions

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Science China Mathematics 2020年第10期63卷 2005-2016页

作者： Rasool Hafezi mohammad hossein Keshavarz School of Mathematics Institute for Research in Fundamental Sciences(IPM)Tehran 19395-5746Iran

Using a relative version of Auslander’s formula,we give a functorial approach to show that the bounded derived category of every Artin algebra admits a categorical ***,in particular,implies that the bounded derived categories of Artin algebras of finite global dimension determine bounded derived categories of all Artin ***,this paper can be considered as a typical application of functor categories,introduced in representation theory by Auslander(1971),to categorical resolutions.

关键词： categorical resolutions Artin algebras Auslander’s formula

Mass and performance optimization of an airplane wing leading edge structure against bird strike using Taguchi-based grey relational analysis

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Chinese Journal of Aeronautics 2016年第4期29卷 934-944页

作者： Hassan Pahange mohammad hossein Abolbashari Department of Mechanical Engineering Ferdowsi University of Mashhad Department of Mechanical Engineering Lean Production Engineering Research Center Ferdowsi University of Mashhad

Collisions between birds and aircraft are one of the most dangerous threats to flight safety. In this study, smoothed particles hydrodynamics(SPH) method is used for simulating the bird strike to an airplane wing leading edge structure. In order to verify the model, first, experiment of bird strike to a flat aluminum plate is simulated, and then bird impact on an airplane wing leading edge structure is investigated. After that, considering dimensions of wing internal structural components like ribs, skin and spar as design variables, we try to minimize structural mass and wing skin deformation simultaneously. To do this, bird strike simulations to 18 different wing structures are made based on Taguchi’s L18 factorial design of experiment. Then grey relational analysis is used to minimize structural mass and wing skin deformation due to the bird strike. The analysis of variance(ANOVA) is also applied and it is concluded that the most significant parameter for the performance of wing structure against impact is the skin thickness. Finally, a validation simulation is conducted under the optimal condition to show the improvement of performance of the wing structure.

关键词： Bird strike Grey relational analysis Multi-objective optimization Smooth particle hydrody namics(SPH) Wing leading edge structure

A New Evaluation Criterion for Optimizing the Mechanical Properties of Toughened Polypropylene/Silica Nanocomposites

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Chinese Journal of Polymer Science 2020年第8期38卷 877-887,I0008页

作者： hossein Pourrahmani Mona Golparvar mohammad Fasihi Group of Energy Materials (E)cole Polytechnique Fédérale de LausanneSion 1951Switzerland School of Chemical Petroleum and Gas EngineeringIran University of Science and TechnologyTehran 16846-13114Iran School of Mechanical Engineering Braunschweig university of technologyBraunschweig 38106Germany

This study aims to experiment with the mechanical properties of polypropylene(PP)/thermoplastic elastomer/nano-silica/compatibilizer nanocomposite using the melt mixing *** addition of polyolefin elastomers has proved to be an approachable solution for low impact strength of PP,while it would also reduce the Young's modulus and tensile *** is why reinforcement would be applied to this combination to enhance the elastic *** mechanical properties of the prepared composites were devised to train an artificial neural network to predict these properties of the system in 6256 unknown ***,the sensitivity analysis was performed and the share of each input parameter on the respective output values was ***,a novel parameter called nanocomposite evaluation criterion(NEC)is introduced to analyze the suitability of the nanocomposites considering the mechanical ***,the formulation with optimal mechanical properties of toughness,elongation at break,tensile strength,Young's modulus,and impact strength was obtained.

关键词： Nanocomposite Polypropylene(PP) Silica Artificial neural networks Nanocomposite evaluation criterion(NEC) Sensitivity analysis