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Chinese Journal of Chemical Engineering 2016年第5期24卷 630-637页

作者： P.Susial D.Garcia R.Susial Y.C.Clavijo A.Martin Escuela de lngenierias lndustriales y Civiles Universidad de Los Palmos de Cran Canafia35017 Los Palmos de Gran CanariaCanary IslandsSpain Dept.lngenieria Qufmica y Tecnologia del Medio Ambiente Universidad de Valladolid.47071 ValladolidSpain

The vapor–liquid equilibrium of binary mixtures of propyl acetate,butyl acetate and isobutyl acetate with methanol has been determined at a constant pressure of 0.6 mpa.Results have been modeled with the Peng–Robinson equation,a traditional cubic equation of state widely employed in chemical industries,as well as with the perturbed-chain statistical associating fluid PC-SAFT theory of Gross–Sadowski.By correlation of the binary interaction parameters of these equations,the measured vapor–liquid equilibrium data can be accurately predicted.Thus,this work shows that these models are able to represent the experimental data for systems with associating compounds via hydrogen bonding.

关键词：混合建模醋酸丁酯 mpa 汽液相平衡乙酸异丁酯乙酸丙酯测定压力

Copper partitioning between granitic silicate melt and coexisting aqueous fluid at 850°C and 100 mpa

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Acta Geochimica 2016年第4期35卷 381-390页

作者： Shuilong Wang Hui Li Linbo Shang Xianwu Bi Xinsong Wang Wenlin Fan State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Geophysical Exploration Institute of Heilongjiang Province Harbin 150036China University of Chinese Academy of Sciences Beijing 100039China

Experiments on the partitioning of Cu between different granitic silicate melts and the respective coexisting aqueous fluids have been performed under conditions of 850 °C, 100 mpa and oxygen fugacity(f O_2) buffered at approaching Ni–Ni O(NNO). Partition coefficients of Cu(DCu= cfluid/cmelt) were varied with different alumina/alkali mole ratios [Al_2O_3/(Na_2O·K_2O), abbreviated as Al/Alk], Na/K mole ratios, and Si O_2 mole contents. The DCu increased from 1.28 ± 0.01 to 22.18 ± 0.22 with the increase of Al/Alk mole ratios(ranging from 0.64 to 1.20)and Na/K mole ratios(ranging from 0.58 to 2.56). The experimental results also showed that DCuwas positively correlated with the HCl concentration of the starting fluid.The DCuwas independent of the Si O_2 mole content in the range of Si O_2 content considered. No DCuvalue was less than 1 in our experiments at 850 °C and 100 mpa, indicating that Cu preferred to enter the fluid phase rather than the coexisting melt phase under most conditions in the melt-fluid system, and thus a significant amount of Cu could be transported in the fluid phase in the magmatichydrothermal environment. The results indicated that Cu favored partitioning into the aqueous fluid rather than themelt phase if there was a high Na/K ratio, Na-rich, peraluminous granitic melt coexisting with the high Cl-fluid.

关键词：硅酸盐熔体花岗质熔体分配系数水溶液 mpa 共存 SiO2含量碱摩尔比

Spearfishing-induced behavioral changes of an unharvested species inside and outside a marine protected area

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Current Zoology 2016年第1期62卷 39-44页

作者： Diem Samantha C. TRAN Katharine A. LANGEL Madison J. THOMAS Daniel T. BLUMSTEIN Department of Ecology and Evolutionary Biology University of California Los Angeles Los Angeles CA90095-1606 USA

By prohibiting fishing, marine protected areas (mpas) provide a refuge for harvested species. Humans are often perceived as predators by prey and therefore respond fearfully to humans. Thus, fish responses to humans inside and outside of an mpa can provide insights into their perception of humans as a predatory threat. Previous studies have found differences in the distance that harvested species of fish initiate flight (flight initiation distance-FID) from humans inside and outside an mpa, but less is known about unharvested species. We focused on whether the lined bristletooth , an unharvested surgeonfish, can discriminate between a snorkeler and a snorkeler with a spear gun inside and outside of a no-take mpa in Mo'orea, French Polynesia. Additionally, we incorporated starting distance (the distance between the person and prey at the start of an experimental approach), a variable that has been found to be important in assessing prey escape decisions in terrestrial species, but that has not been extensively studied in aquatic systems. Lined bristletooth FID was significantly greater in the presence of a spear gun and varied depending on if the spear gun encounter was inside or outside of the mpa. These results imply a degree of sophistication of fish antipredator behavior, generate questions as to how a nontargeted species of fish could acquire fear of humans, and demonstrate that behavioral surveys can provide insights about antipredator behavior.

关键词：海洋保护区反捕行为热带鱼收割种内 mpa 食肉动物水生系统

Properties and homogeneity of 550-mpa grade TMCP steel for ship hull

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International Journal of Minerals,Metallurgy and Materials 2010年第2期17卷 179-184页

作者： Yi Nie Cheng-jia Shang Xin Song Yang You Chuang Li Xin-lai He School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Department of Physics and Chemistry Henan Polytechnic University Jiaozuo 454000 China

由有更少的 Ni ， Cr ，和瞬间内容的热机械控制 processTMCP 的极端低碳钢为 550 mpa 等级被开发了重计量器轮船壳并且近海在微观结构之中的 structures.The 关系，进程，并且学习的钢的性质是精确控制技术的 investigated.A 系列为这... 详细信息

由有更少的 Ni ， Cr ，和瞬间内容的热机械控制 processTMCP 的极端低碳钢为 550 mpa 等级被开发了重计量器轮船壳并且近海在微观结构之中的 structures.The 关系，进程，并且学习的钢的性质是精确控制技术的 investigated.A 系列为这种 steel.Cu microalloying 和 TMCPrelaxation 降水 controlRPCaccelerated

关键词：机械性能控轧控冷 mpa 低碳钢船体热机械控制工艺 TMCP工艺微观结构

Influence of carbon content on microstructure and mechanical properties of 1000 mpa deposited metal by gas metal arc welding

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Journal of Iron and Steel Research(International) 2019年第5期26卷 512-518页

作者： Tong-bang An Jin-shan Wei Lin Zhao Ji-guo Shan Zhi-ling Tian Central Iron & Steel Research Institute Beijing 100081 China Department of Mechanical Engineering Tsinghua University Beijing 100084 China

The effects of carbon content (0.078-0.100 wt.%) on the microstructure and properties of 1000 mpa grade deposited metal produced by gas metal arc welding have been investigated. Experimental results show that the microstructure of the deposited metal was mainly composed of martensite, bainite and retained austenite. With increasing carbon content, the proportion of martensite increased, and the amount of bainite was reduced. High carbon content is beneficial to strength, but harmful to impact toughness, and thus, carbon reductions lead to the increase in impact toughness. When the carbon content was 0.100 wt.%, the lowest Charpy absorbed energy of 47 J at — 40℃ for the deposited metal was achieved, the highest yield strength of 1038 mpa was attained, and the yield-to-tensile ratio was more than 0.88, while the highest Charpy absorbed energy of 55.7 J at — 40℃ and the lowest yield strength of 915 mpa were obtained when the deposited metal contains 0.078 wt.% C, and the yield-to-tensile ratio was less than 0.85. It is concluded that bainite fraction and fine effective grain size were the dominant factors to achieve good comprehensive mechanical properties (the required strength and an acceptable toughness) of deposited metals with various carbon contents.

关键词： 1000 mpa grade deposited metal Carbon content Microstructure Strength Gas metal arc welding Impact toughness

Abrasive Wear Characteristics of Carbon and Low Alloy Steels for Better Performance of Farm Implements

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Journal of Materials Science & Technology 1995年第2期11卷 91-96页

作者： M.Kumar and R. C Gupta(Centre of Advanced Study, Dept. of Metallurgical Engineering, Institute of Technology,Banaras Hindu University, Vaanasi -221 005, India) Banaraz Hindu Univ Varanasi India

The low stress abrasion behaviours of heat treated mild, medium carbon and high C - low Cr steels, which are generally used in making farm implements, have been investigated. The simple heat treatment greatly improves the hardness, tensile strength and abrasion resistance of medium carbon and high C - low Cr steels. The results indicate that the material removal during abrasion is controlled by a number of factors, such as hardness, chemical composition, microstructure and heat treatment conditions. The conclusion is that the heat treated high C - low Cr steel and mild steel carburized by using coaltar pitch provide the best hardness and abrasion resistance and thus appear to be the most suitable materials for making agricultural tools.

关键词： Abrasive Wear Characteristics of Carbon and Low Alloy Steels for Better Performance of Farm Implements mpa

Microstructure and Mechanical Properties of Si_3N_4 Composites Containing SiC Platelet

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Journal of Materials Science & Technology 1998年第2期14卷 151-155页

作者： Tao WEI Yu ZHOU Tingquan LEI and Yujin WANG (School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China) School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

Hoppressed Si3N4/SiC platelet composites had been investigated with respect to their microstructure and mechanical properties. The results indicate that Vickers hardness, elastic modulus and fracture toughness of the composites were increased by the addition of SiC platelet until the content up to 20 vol pct. A slight decrease in flexural Strength was measured at room temperature with increasing SiC platelet content. The high temperature flexural strength tests at 1150, 1250, and 1350℃ were conducted. It was found that the flexural strength at elevated temperature was degraded with the rising temperature, and the downward trend of flexural strength for the composite containing 10 vol. pct SiC platelet was less. The results indicate that SiC platelet had a positive influence on the high temperature strength. Effects of SiC platelet reinforcement were presented

关键词： SiC Microstructure and Mechanical Properties of Si3N4 Composites Containing SiC Platelet mpa

Carbon foams prepared from coal tar pitch for building thermal insulation material with low cost

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Chinese Journal of Chemical Engineering 2018年第2期26卷 415-420页

作者： Xiang Liu Yanli Wang Liang Zhan State Key Laboratory of Chemical Engineering East China University of Science and Technology Key Laboratory for Specially Functional Polymers and Related Technology of Ministry of Education East China University of Science and Technology Shanghai Key Laboratory of Multiphase Materials Chemical Engineering East China University of Science and Technology CAS Key Laboratory of Carbon Materials Institute of Coal Chemistry Chinese Academy of Sciences

A new approach is provided to resolve the large-scale applications of coal tar pitch. Carbon foams with uniform pore size are prepared at the foaming pressure of normal pressure using coal tar pitch as raw materials. The physical and chemical performance of high softening point pitch(HSPP) can be regulated by vacuumizing owing to the cooperation of vacuumizing and polycondensation. Results indicate that the optimum softening point and weight ratio of quinoline insoluble are about 292℃ and 65.7%, respectively. And the optimum viscosity of HSPP during the foaming process is distributed in the range of 1000-10000 Pa·s. The resultant carbon foam exhibits excellent performance, such as uniform pore structure, high compressive strength(4.7 mpa), low thermal conductivity(0.07 W·m^(-1) ·K^(-1)), specially, it cannot be fired under the high temperature of 1200 ℃.Thus, this kind of carbon foam is a potential candidate for thermal insulation material applied in energy saving building.

关键词：煤焦油沥青屏蔽材料碳泡沫低费用真空包装应用程序 mpa tar

Multifunctional high-performance 10-J level laser system

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Chinese Optics Letters 2014年第4期12卷 43-47页

作者：彭宇杰王江峰张志祥黄大杰范薇李学春 Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences University of Chinese Academy of Sciences

In this letter, we report a multifunctional high-performance Nd：glass laser system. Laser pulses from an all-fiber front end are first amplified by a regenerative amplifier to 10 mJ level, and then further amplified in a four-pass amplifier. The laser system can provide 10.3-J, 3-ns laser pulses at 1053-nm wavelength. The shot-to-shot energy stability is better than 1.5% （RMS）. The output laser beam is near diffraction limit. Binary amplitude masks are used to maintain a flat top near-field profile with a 71% fill factor. After the frequency conversion process, 7 and 5.5 J pulses at 526.5 and 351 nm are obtained, respectively.

关键词： high Multifunctional high-performance 10-J level laser system mpa MOPA KDP Nd RMS HWP

Performance Analysis of ACO-OFDM Visible Light Communication System Based on SCMA

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Journal on Internet of Things 2022年第4期4卷 215-225页

作者： Xiukai Ruan Shahid Iqbal Awan Institute of Intelligent Lock Wenzhou UniversityWenzhouChina University of Poonch Rawalakot RawalakotPakistan

A SCMA ACO-OFDM downlink visible light communication(VLC)system is proposed.Six users share four spectrum resources,four of which are 4 primary color LED lights.ACO-OFDM technology is used to convert the user’s sparse codebook mapped signal into a positive real value signal that can be carried on the light wave,which can realize high-speed parallel communication.Simulation verifies the feasibility of the system.At the same time,the channel model of visible light communication is constructed,and the signal-to-noise ratio(SNR)and channel gain of the visible light channel are systematically analyzed.Finally,the theoretical bit error rate formula using mpa decoding algorithm under different codebook constellation mapping points is given.Through simulation,it is verified that the theoretical bit error rate formula is basically consistent with the simulation bit error rate formula.

关键词： SCMA ACO-OFDM visible light communication SNR mpa bit error rate