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Prediction model for determining the optimum operational parameters in laser forming of fiber-reinforced composites

Advances in Manufacturing 2020年第2期8卷 242-251页

作者： Annamaria Gisario mehrshad mehrpouya Atabak Rahimzadeh Andrea De Bartolomeis Massimiliano Barletta Department of Mechanical and Aerospace Engineering Sapienza University of RomeVia Eudossiana 1800184 RomeItaly Department of Mechanical and Industrial Engineering The University of Roma TreVia Vito Volterra 6200146 RomeItaly Department of Mechanical Engineering University of BathBath BA27AYUK

Composite materials are widely employed in various industries,such as aerospace,automobile,and sports equipment,owing to their lightweight and strong structure in comparison with conventional materials.I aser material processing is a rapid technique for performing the various processes on composite materials.In particular,laser forming is a flexible and reliable approach for shaping fiber-metal laminates(FML.s),which are widely used in the aerospace industry due to several advantages,such as high strength and light weight.In this study,a prediction model was developed for determining the optimal laser parameters(power and speed)when forming FML composites.Artificial neural networks(ANNs)were applied to estimate the process outputs(temperature and bending angle)as a result of the modeling process.For this purpose,several ANN models were developed using various strategies.Finally,the achieved results demonstrated the advantage of the models for predicting the optimal operational parameters.

关键词： Laser forming(LF) Fiber-reinforced composite Fiber-metal laminates(FMLs) Glass laminate aluminum reinforced epoxy(GLARE) Artificial neural networks(ANNs)

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Plasma Sprayed NiAl Intermetallic Coating Produced with Mechanically Alloyed Powder

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Journal of Materials Science & Technology 2011年第9期27卷 816-820页

作者： mehrshad Moshref Javadi Hossein Edris Mahdi Salehi Marine Engineering Department Maleke-Ashtar University of Technology Department of Materials Engineering Isfahan University of Technology

In the present research, mechanically alloyed Ni-AI powder was utilized to develop plasma sprayed coatings, and the effect of the spray distance and heat treatment on the phases, microstructure, and hardness of the coat- ings were examined. Coatings were analyzed by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, energy-dispersive spectroscopy （EDS） and through microhardness measurements. Although mechanically alloyed Ni-AI powder showed no intermetallic phases, the coatings did. Different spray distances from 5 to 19 cm were employed for plasma spray and the specimens were heat treated at different temperatures, then the amount of oxides, porosity and hardness of the coatings were changed according to the spray condition. The thermal energy of the plasma spray caused the formation of NiAI phases while particles flew to the substrate or after that. Extreme increase in heat treatment temperature and spray distance resulted in oxidation and reduction in the quality of the coating. Furthermore, the best spray distance and heat treatment temperature to gain the NiAI intermetallic coating were established.

关键词： Coating materials Intermetallics Phase transformation Plasma spray

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Layered material GeSe and vertical GeSe/MoS2 p-n heterojunctions

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Nano Research 2018年第1期11卷 420-430页

作者： Wui Chung Yap Zhengfeng Yang mehrshad Mehboudi Jia-An Yan Salvador Barraza-Lopez Wenjuan Zhu Department of Electrical and Computer Engineering University of Illinois at Urbana-Champaign Urbana IL 6180 I USA Department of Physics University of Arkansas Fayetteville AR 72701 USA Department of Physics Astronomy & Geosciences Towson University Towson MD 21252 USA

GroupqV monochalcogenides are emerging as a new class of layered materials beyond graphene, transition metal dichalcogenides （TMDCs）, and black phosphorus （BP）. In this paper, we report experimental and theoretical investigations of the band structure and transport properties of GeSe and its heterostructures. We find that GeSe exhibits a markedly anisotropic electronic transport, with maximum conductance along the armchair direction. Density functional theory calculations reveal that the effective mass is 2.7 times larger along the zigzag direction than the armchair direction; this mass anisotropy explains the observed anisotropic conductance. The crystallographic orientation of GeSe is confirmed by angle- resolved polarized Raman measurements, which are further supported by calculated Raman tensors for the orthorhombic structure. Novel GeSeflVIoS2 p-n heterojunctions are fabricated, combining the natural p-type doping in GeSe and n-type doping in MoS2. The temperature dependence of the measured junction current reveals that GeSe and MoS2 have a type-II band alignment with a conduction band offset of N 0.234 eV. The anisotropic conductance of GeSe may enable the development of new electronic and optoelectronic devices, such as high-efficiency thermoelectric devices and plasmonic devices with resonance frequency continuously tunable through light polarization direction. The unique GeSe/MoS2 p-n junctions with type-II alignment may become essential building blocks of vertical tunneling field-effect transistors for low-power applications. The novel p-type layered material GeSe can also be combined with n-type TMDCs to form heterogeneous complementary metal oxide semiconductor （CMOS） circuits.

关键词： monochalcogenides,germanium selenide,anisotropic conductance,polarized Raman,p-n heterojunction

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Gorgan Bay： a microcosm for study on macrobenthos speciesenvironment relationships in the southeastern Caspian Sea

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Acta Oceanologica Sinica 2016年第4期35卷 82-88页

作者： GHASEMI Amir Faraz TAHERI mehrshad FOSHTOMI Maryam Yazdani NORANIAN Majid MIRA Seyed Sahab JAM Armin Iranian National Institute for Oceanography and Atmospheric Science (INIOAS) Tehran *** Iran Department of the Environment Golestan Province Gorgan *** Iran

The relationship between spatial patterns of macrobenthos community characteristics and environmental conditions（salinity, temperature, dissolved oxygen, organic matter content, sand, silt and clay） was investigated throughout the Gorgan Bay in June 2010. Principal components analysis（PCA） based on environmental data separated eastern and western stations. The maximum（4 500 ind./m2） and minimum（411 ind./m2） densities were observed at Stas 1 and 6, respectively. Polychaeta was the major group and Streblospio gynobranchiata was dominant species in the bay. According to Distance Based Linear Models results, macrofaunal total density was correlated with silt percentage and salinity and these two factors explaining 64% of the variability while macrofaunal community structure just correlated with salinity（22% total variation）. In general, western part of the bay showed the highest number of species and biodiversity while, the highest density was found at Sta. 1 and in the middle part of the bay. Furthermore, relationship between diversity indices and macrobenthic species with measured factors is also discussed. Our results confirm the effect of salinity as an important factor on distribution of macrobenthic fauna in south Caspian brackish waters.

关键词： salinity macrobenthos species-environment relationship Gorgan Bay Caspian Sea

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Nematode community structure in relation to metals in the southern of Caspian Sea

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Acta Oceanologica Sinica 2017年第10期36卷 79-86页

作者： Kazem Darvish Bastami mehrshad Taheri Maryam Yazdani Foshtomi Sarah Haghparast Ali Hamzehpour Hossein Bagheri Marjan Esmaeilzadeh Neda Molamohyeddin Iranian National Institute for Oceanography and Atmospheric Science (INIOAS) Department of Fisheries Faculty of Animal Science and Fisheries Sari Agricultural Sciences and Natural Resources University Department of Environmental Science Faculty of Environment and Energy Science and Research Branch Islamic Azad University Department of Marine Science and Technology Tehran North Branch Islamic Azad University

Spatial distribution and structure of nematode assemblages in coastal sediments of the southern part of the Caspian Sea were studied in relation to environmental factors. By considering metals, organic matter, Shannon diversity index（H）, maturity index（MI） and trophic diversity（ITD）, ecological quality status of sediment was also determined. Fifteen nematode species belonging to eleven genera were identified at the sampling sites. Average density of nematode inhabiting in sediment of the studied area was 139.78±98.91（ind. per 15.20 cm^2）. According to redundancy analysis（RDA）, there was high correlation between metals and some species. Based on biological indicators, the studied area had different environmental quality. Generally, chemical and biological indices showed different results while biological indices displayed similar results in more sites.

关键词： free-living nematodes metal ecological quality status the Caspian Sea

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Survey on cattle ticks in Nur,north of Iran

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Asian Pacific Journal of Tropical Biomedicine 2014年第3期4卷 209-212页

作者： Ashkan Ghasemi Moghaddam Mozafar Razavi Seyed mehrshad Rasouli Sajad Hosseinzade Mohammad Mehdi Darvishi Arash Rakhshanpour Mohammad Taghi Rahimi Young Researchers Club Islamic Azad UniversityBabot BranchIran Department of Veterinary Parasitology Semnan UniversitySemnanIran Department of Medical Parasitology and Mycology School of Public HealthTehran University of Medical SciencesTehranIran Department of Parasitology and Mycology School of MedicineMazandaran University of Medical ScienceSariIran Young Researchers Club Islamic Azad UniversityBabol BranchIran

Objective:To survey the prevalence of cattle ticks in Nur County and prepare a list of tick fauna in this district.Methods:This investigation was carried out on 150 head of cattle ticks of rural areas of Nur city which is located in Mazandaran province during spring and summer seasons of 2011.The collected ticks were identified using light microscope and available systematic keys.Results:A total number of 1563 ticks were isolated from examined cattle and their genus and numbers including:lxodes ricinus 51%(111 male and 691 female)and Boophilus annulatus 49%(83male and 678 female),respectively.Conclusions:Results of the current investigation indicate the presence of two species of acarine ectoparasites which have potential health risk lxodes ricinus and Boophilus annulatus.More studies are required to increase our data concerning ticks and other ectopreasites of ruminants in other areas of Mazandaran province and should be noted to their ability in transmission of infectious agents.

关键词： Acarine ecotoparasites Tick Livestock Cattle Public health risk Iran

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