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Profile of *** Chen

Science China(Life Sciences) 2024年第10期67卷 2062-2063页

作者： Chen, Songlin Yellow Sea Fisheries res.inst Qingdao Peoples R China

For decades,*** has been engaged in fish germplasm pres.rvation,sex control and res.arch focusing on molecular breeding for disease *** discovered the first sex-specific molecular marker of fish(Chen et al.,2007),deciphered the first fish genome(Chinese tongue sole)in China,revealed the sex determination mechanism in fish(Chen et al.,2014),and created molecular sex control *** also discovered the molecular mechanism of metamorphosis in flatfish(Shao et al.,2017)and developed China's first fish disease-res.stant breeding gene chip,“YUXIN No.1”.

关键词： technology breeding

thermal Activation Analyses of Dynamic FractureToughness of High Strength Low Alloy Steels

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Journal of Materials Science & Technology 2001年第2期17卷 215-218页

作者： Cunjian LI and Shaohua LI Welding res.arch Department, Central Iron & Steel res.arch inst.tute, Beijing 100081, China Yuqing DENG State Administration of Metallurgical Industry, Beijing 100711, China Dept. of Welding res. Central Iron and Steel Res. Inst. Beijing 100081 China

A formula is derived for determining the influence of temperature and loading rate on dynamic fracture toughness of a high strength low alloy steel (HQ785C) from thermal activation analysis of the experimental res.lts of three-point bend specimens as well as introducing an Arrhenius formula. It is shown that the res.lts obtained by the given formula are in good agreement with the experimental ones in the thermal activation region. the pres.nt method is also valuable to describe the relationship between dynamic fracture toughness and temperature and loading rate of other high strength low alloy steels.

关键词： test GB thermal Activation Analyses of Dynamic FractureToughness of High Strength Low Alloy Steels

Mechanism of Burn res.stance of Alloy Ti40

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Journal of Materials Science & Technology 2001年第6期17卷 677-678页

作者： Yongqing ZHAO, Lian ZHOU,Kanging ZHU,Henglei QU and Huan WU Northwest inst.tute for Nonferrous Metal res.arch, Xi’an 710016, China [Manuscript received June 5, 2000] inst. for Nonferrous Metal res. Xi'an 710016 China

the Ti fire found in high performance engines promotes the development of burn res.stant Ti alloys. the burn res.stant mechanism of Ti40 alloy is investigated. Ti40 alloy reveals good burn res.stance. Its interfacial products between burning products and the matrix are tenacious, which retard the diffusion of oxygen into the matrix. Two burn res.stant mechanisms, that is, fast scatter dispersion of heat and suppres.ion of oxygen diffusion, are proposed.

关键词： Ti Mechanism of Burn res.stance of Alloy Ti40

STUDIES ON GREY MODEL DYNAMIC PREDICTION TO CAVITATION DAMAGE OF TURBINES

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Journal of Hydrodynamics 2003年第5期15卷 29-34页

作者： Wu Fu sheng, Tong Zhong shan, Li Yun hui Nanjing Hydraulic res.arch inst.tute, Nanjing 210029, China Nanjing Hydraulic res. inst. Nanjing 210029 China

In thus paper, cavitation damage of turbines is firstly analyzed andpredicated from the view point of system engineering by use of the grey system theory. A detaileddescription of modeling, dynamic prediction and accuracy test for the grey system of turbines wasgiven. Two special cases for grey dynamic prediction as well as its accuracy test were *** res.lts fall into the grade I, the accuracy is satisfactory and its prediction requirements canbe met well. It shows that the grey system theory can be employed to predict the cavitation damageof turbines, and it can provide a scientific basis for timely investigation and maintenance ofturbines.

关键词： turbine cavitation damage grey prediction

HYDRAULICS OF COMPOUND CHANNEL WIth VEGETATED FLOODPLAINS

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Journal of Hydrodynamics 2002年第1期14卷 23-28页

作者： Huang Ben-sheng, Lai Guan-wen, Qiu Jing, Lin Shu-zhong (Guangdong res.arch inst.tute of Water Conservancy & Hydro-Power, Guangzhou 510610, China res. inst. of Water Conservancy Guangzhou 510610 China

Experimental res.arches were conducted on flood carrying capacity of compound open channels with wide and narrow floodplains as well as hydrodynamic behavior of overbank flow across vegetated floodplains. res.lts show that hydrodynamic behavior of compound channels with narrow floodplains is different from that of the wide floodplains. In such compound channels with narrow vegetated floodplains as in the Pearl River delta nework, it has been found that vegetated domains become really impenetra ble when the length of vegetated domain is larger than Lm, the length of f low in floodplain coming into the main channel, and that the influence of vegeta ted floodplains upon flood stages of a channel is not very significant.

关键词： compund chennel vegetated floodplains flood carrying capacity velocity distributions the Pearl River delta

Martensitic Transformation and Magnetic-Field-Induced Strain in Magnetic Shape Memory Alloy NiMnGa Melt-Spun Ribbon

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Journal of Materials Science & Technology 2005年第2期21卷 211-214页

作者： Shihai GUO, Yanghuan ZHANG, Jianliang LI, Baiyun QUAN, Yan QI and Xinlin WANG Department of Functional Material res.arch, Central Iron and Steel res.arch inst.tute, Beijing 100081, China Dept. of Functional Mat. res. Central Iron and Steel Res. Inst. Beijing 100081 China

A magnetic shape memory alloy with nonstoichiometric Ni50Mn27Ga23 was prepared by using melt-spinning technology. the martensitic transformation and the magnetic-field-induced strain (MFIS) of the polycrystalline melt-spun ribbon were investigated. the experimental res.lts showed that the melt-spun ribbons underwent thermal-elastic martensitic transformation and reverse transformation in cooling and heating process and exhibited typical thermo-elastic shape memory effect. However the start temperature for martensitic transformation decreased from 286 K for as-cast alloy to 254 K for as-quenched ribbon and Curie temperature remains approximately constant. A particular internal stres. induced by melt-spinning res.lted in the formation of a texture structure in the ribbons, which made the ribbons obtain larger martensitic transformation strain and MFIS. the internal stres. was released substantially after annealing, which res.lted in a decrease of MFIS of the ribbons.

关键词： Shape memory alloy Ferromagnetism Melt-spinning Martensitic transformation Magnetic-field-induced strain

Effect of Barium-Precursors on Reaction Kinetics in Y-Ba-Cu-O System

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Journal of Rare Earths 2001年第4期19卷 241-245页

作者：王龙妹 Central Iron and Steel res. inst. Beijing 100081 China

the reactions of stoichiometric Y2O3, CuO, and different Ba salts or oxides (BaCO3, Ba(NO3)(2), BaO2, BaCuO2) for forming various compounds in the Y-Ba-Cu-O system (i.e., YBa2Cu3O7-delta, BaCuO2, Y2BaCuO5 and Y2Cu2O5) were systematically investigated by thermal analysis and X-ray diffractometry. the relevant activation energies were calculated from thermogravimetric data. It is found that the reaction pathway significantly depends on the thermal stability of the Ba precursors. Binary BaO-CuO phases form at low temperature (650 similar to 700 degreesC) when in pres.nce of easy- to -decompose Ba precursors, and then slowly transform to ternary compounds. On the contrary, when Ba ions are released at temperature higher than 900 degreesC, ternary phases form directly from the components.

关键词： rare earths Y-Ba-Cu-O precursors sequencing kinetics

MODELING OF MICROMANIPULATION ROBOT IN VIRTUAL ENVIRONMENT

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Acta Metallurgica Sinica(English Letters) 2004年第2期17卷 194-198页

作者： F.S.Tan L.N.Sun W.B.Rong J.Zhu Robotic res.arch inst.tute,Harbin inst.tute of Technology,Harbin 150001,China Robotic res. inst. Harbin Inst. of Technol. Harbin 150001 China

Micromanipulation has been recognized to be very difficult due to the inefficiency oftraditional micromanipulation methods. the paper pres.nt a general framework formicromanipulation robot based on virtual reality technology. the significance of in-troducing virtual reality into micromanipulation is analyzed, and the current res.archin this field is reviewed. Based on this, we propose a micromanipulation system thatintegrates virtual environment with vision feedback and force feedback. the systemrealizes vision close-loop control and force close-loop control to enhance the perfor-mance of micromanipulation device. A graphics modelling method is proposed for amicroassembly task. Hardware and software implementation is described and discus-sion about the res.arch is pres.nted.

关键词： micromaniqulation virtual reality vision feedback force feedback microassembly

Study on Fine Structure of Gas Atomized LaNi_5-based Alloys

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Journal of Materials Science & Technology 2003年第5期19卷 425-427页

作者： Hai JING, Hong GUO, Shuguang ZHANG, Zili MA and Shaoming ZHANGNational Engineering res.arch Center for Non-ferrous Metals Composites, General res.arch inst.tute for Non-ferrous Metals, Beijing 100088, China Natl. Eng. res. Ctr. Res. Inst. of Non-Ferrous Metals Beijing 100088 China

the fine structure of hydrogen storage alloy powders MiNi4.3-xCoxMr0.4AI0.3(x=0.75, 0.45, 0.10; Ml: La-rich misch metal) prepared by rapidly solidifying gas atomization was investigated using a Rietveld analysis method. Two sets of CaCu5-type crystal constants were observed in the studied alloys and one set was larger than the other. With decreasing powder radius the solidification rate of powder increased, and so did the percentage of a particle part with larger crystal constants. the reason why there were two sets of crystal constants might be the difference of solidification rate between the outside and inside of a particle.

关键词： Hydrogen storage alloys Gas atomization Rietveld analysis Crystal structure