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Phase transformation kinetics of Ti-1300 alloy during continuous heating

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Rare Metals 2015年第4期34卷 233-238页

作者： Ming-Pan Wan Yong-Qing Zhao wei-dong zeng State Key Laboratory of Solidification Processing Northwest Polytechnical University College of Materials and Metallurgy Guizhou University Northwest Institute for Nonferrous Metal Research

Abstract The α ＋ β→β phase transformation kinetics of Ti-1300 alloy during continuous heating at different heating rates were investigated using dilatometric method. Results show that the curves of the α ＋ β→β phase transformation exhibit a typical S-shaped pattern, which indicates that the α ＋ β→β phase transformation is a nucleation-growth-controlled process. The overall activation energy of the α ＋ β→β transformation of the alloy is 797 kJ·mol^-1. The nucleation and growth mechanism of the α ＋ β→β transformation was also investigated using the non-isothermal Avrami exponent. The Avrami exponent during α ＋ β→β transformation process significantly changes with transformed volume fraction increasing, which indicates that the α ＋ β→β transformation mechanism in the Ti-1300 alloy varies at different sections.

关键词： Ti-1300 alloy Phase transformation Dilatometry Kinetics

Development of a database system for operational use in the selection of titanium alloys

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International Journal of Minerals,Metallurgy and Materials 2011年第4期18卷 444-449页

作者： Yuan-fei Han wei-dong zeng Yu Sun Yong-qing Zhao State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi＇an 710072 China Northwest Institute for Nonferrous Metal Research Xi＇an 710016 China

The selection of titanium alloys has become a complex decision-making task due to the growing number of creation and utilization for titanium alloys,with each having its own characteristics,advantages,and *** choosing the most appropriate titanium alloys,it is very essential to offer a reasonable and intelligent service for technical *** possible solution of this problem is to develop a database system（DS） to help retrieve rational proposals from different databases and information sources and analyze them to provide useful and explicit *** this purpose,a design strategy of the fuzzy set theory is proposed,and a distributed database system is *** ranking of the candidate titanium alloys,the most suitable material is *** is found that the selection results are in good agreement with the practical situation.

关键词： titanium alloys database system fuzzy set theory evaluation

Follicle-stimulating hormone promotes proliferation of cultured chicken ovarian germ cells through protein kinases A and C activation

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第12期11卷 952-957页

作者： Hong-yun LIU wei-dong zeng Ai-ling CAO Cai-qiao ZHANG Key Laboratory of Animal Epidemic Etiology and lmmunological Prevention of the Ministry of Agriculture College of Animal Sciences Zhejiang University Hangzhou 310029 China Xiaoshan Entry-Exit Inspection and Quarantine Bureau Hangzhou 311208 China

The study was conducted to investigate the effects of follicle-stimulating hormone (FSH) on embryonic chicken ovarian germ cell proliferation and its possible involvements of protein kinases A (PKA) and C (PKC) *** cells were treated with FSH alone or in the presence of forskolin (FRSK),PKA inhibitor (H89),PKC activator (PMA) or inhibitor (H7).The germ cell number was counted from *** immunocytochemistry of proliferating cell nuclear antigen (PCNA) was applied to identify the proliferating *** germ cell labeling index (LI) was determined for cell *** FSH treatment increased the germ cell number,and this stimulating effect was enhanced by FRSK or PMA,but inhibited by H89 or H7 in a dose-dependent ***,the PCNA-LI showed parallel changes with germ cell *** study suggests that FSH may stimulate proliferation of cultured chicken ovarian germ cells by activation of both the PKA and PKC signaling pathways.

关键词： Follicle-stimulating hormone Protein kinase A Protein kinase C Germ cell Proliferation

Shear-Banding Evolution Dynamics during High Temperature Compression of Martensitic Ti-6Al-4V Alloy

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Chinese Physics Letters 2020年第11期37卷 55-59页

作者： Xue-Hua Zhang Rong Li Yong-Qing Zhao wei-dong zeng State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an 710072China Western Metal Materials Co. LTDXi'an 710021China Northwest Institute for Nonferrous Metal Research Xi'an 710016China

The isothermal compression dynamics of ternary Ti-6 Al-4 V alloy with initial martensitic structures were investigated in the high temperature range 1083-1173 K and moderate strain rate regime 0.01-10 *** banding was found to still dominate the deformation mechanism of this process,despite its nonadiabatic *** constitutive equation was derived with the aid of Zener-Hollomon parameter,which predicted the apparent activation energy as 534.39 kJ/mol.A combination of higher deformation temperature and lower strain rate suppressed the peak flow stress and promoted the evolution of shear *** experiments and calculations demonstrated that a conspicuous temperature rise up to 83 K could be induced by severe plastic *** facilitated the dynamic recrystallization of deformed martensites,as evidenced by the measured microhardness profiles across shear bands.

关键词： deformation martensite recrystallization

Methods and mechanisms for uniformly refining deformed mixed and coarse grains inside a solution-treated Ni-based superalloy by two-stage heat treatment

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Journal of Materials Science & Technology 2021年第18期77卷 47-57页

作者： Guan-Qiang Wang Ming-Song Chen Hong-Bin Li Y.C.Lin wei-dong zeng Yan-Yong Ma School of Mechanical and Electrical Engineering Central South UniversityChangsha 410083China Light Alloy Research Institute Central South UniversityChangsha 410083China State Key Laboratory of High Performance Complex Manufacturing Changsha 410083China College of Metallurgies and Energy North China University Science and TechnologyTangshan 063009China

The uniform refinement mechanisms and methods of deformed mixed and coarse grains inside a solution-treatment Ni-based superalloy during two-stage annealing treatment have been *** two-stage heat treatment experiments include an aging annealing treatment(AT)and a subsequent recrystallization annealing treatment(RT).The object of AT is to precipitate someδphases and consume part of storage energy to inhibit the grain growth during RT,while the RT is to refine mixed and coarse grains by *** can be found that the recrystallization grains will quickly grow up to a large size when the AT time is too low or the RT temperature is too high,while the deformed coarse grains cannot be eliminated when the AT time is too long or the RT temperature is too *** addition,the mixed microstructure composed of some abnormal coarse recrystallization grains(ACRGs)and a large number of fine grains can be observed in the annealed specimen when the AT time is 3 h and RT temperature is 980℃.The phenomenon attributes to the uneven distribution ofδphase resulted from the heterogeneous deformation energy when the AT time is too *** the regions with a large number ofδphases,the recrystallization nucleation rate is promoted and the growth of grains is limited,which results in fine ***,in the regions with fewδphases,the recrystallization grains around grain boundaries can easily grow up,and the new recrystallization nucleus is difficult to form inside grain,which leads to ***,in order to obtain uniform and fine annealed microstructure,it is a prerequisite to precipitate even-distributedδphase by choosing a suitable AT time,such as 12 ***,a relative high RT temperature is also needed to promote the recrystallization nucleation aroundδ*** optimal annealing parameters range for uniformly refining mixed crystal can be summarized as:900℃×12 h+990℃×(40-60 min)and 900℃×12 h+1000℃×(10-15 min).

关键词： Ni-based superalloy Aging annealing Recrystallization annealing Grain refinement Microstructural evolution Mixed grain microstructure

Attenuating effect of daidzein on polychlorinated biphenyls-induced oxidative toxicity in mouse testicular cells

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第7期9卷 567-571页

作者： Da-lei ZHANG Yu-ling MI Kai-ming WANG wei-dong zeng Cai-qiao ZHANG College of Animal Sciences Zhejiang University Hangzhou 310029 China Department of Physiology College of Medicine Nanehang University Nanehang 330006 China

The attenuating effect of daidzein (DAI) on oxidative toxicity induced by Aroclor 1254 (A1254) was investigated in mouse testicular cells. Cells were exposed to A1254 alone or with DAI. The oxidative damage was estimated by measuring malondialdehyde (MDA) formation, superoxide dismutase (SOD) activity and glutathione (GSH) content. Results show that A1254 induced a decrease of germ cell number, an elevation in thiobarbituric acid reactive substances (TBARS) but a decrease in SOD activity and GSH content. However, simultaneous supplementation with DAI decreased TBARS level and increased SOD activity and GSH content. Consequently, dietary DAI may restore the intracellular antioxidant system to attenuate the oxidative toxicity of A1254 in testicular cells.

关键词： Daidzein (DAI) Polychlorinated biphenyl (PCB) Oxidative damage. Germ cell

Histological observation of some primitive euconodonts of Late Cambrian from Liaoning

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Progress in Natural Science:Materials International 2005年第12期15卷 1084-1088页

作者： GUO wei,dong Xiping,zeng Xiaochun and ZHAO Le Department of Geology,College of Environmental Science,Peking University,Beijing 100871,China Department of Geology College of Environmental Science Peking University Beijing 100871 China. College of Environmental Science Peking University Beijing 100871 China

The histology of some euconodonts of Late Cambrian from Benxi and Fuxian County,Liaoning Province is studied by the oil-immersion *** histological characteristics of six primitive species of euconodonts - Proconodontus muelleri,Proconodontus tenuiserratus,Granatodontus ani,Rotundoconus tricarinatus,Teridontus nakamurai and Cordylodus proavus are described in *** dentine and atubular (parallel- and wavy-lamellar) dentine are found in the basal bodies of the primitive euconodonts Proconodontus tenuiserratus and Proconodontus muelleri,*** tubular dentine and spherulitic dentine are also recognized from the basal bodies of Granatodontus ani and Rotundoconus *** the histological characteristics of the studied six species of euconodonts belonging to Proconodontus lineage and Teridontus lineage Sensu Miller (Univ Kansas Paleontol Contr,1980,99: 1-39) seems to be almost the same,euconodonts are proposed as possibly monophyletic herein.

关键词： histology primitive euconodonts Late Cambrian Liaoning

STUDY ON THE WIND AND WAVE EXTREME PARAMETERS OF TONKIN GULF IN THE SOUTH CHINA SEA-THE APPLICATIONS OF LAGFD NUMERICAL MODELS

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Journal of Hydrodynamics 1997年第1期9卷 75-86页

作者： Qiao Fang-li, Yu wei-dong, Pan zeng-diThe First Institute of Oceanography, SOA,Qingdao 266003,P. R. China The First Inst of Oceanography Qingdao China

Based on the hindcast of the severest 75 tropical cyclones (hereafter is called TCs) which affected Tonkin Gulf in history, the present paper gives sea surface wind and wave extreme parameters at 38 points corresponding to (1/2)×(1/2)?grid in the Gulf. The research increases our understanding of the meteo-ocean conditions on the whole area and provides basic data for ocean environmental research and engineering design.

关键词： wind,wave,gulf,ocean environmental research extreme parameters

Physical properties of WSTi3515S burn-resistant titanium alloy

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Rare Metals 2016年第5期35卷 361-366页

作者： Yun-Jin Lai Ping-Xiang Zhang Xue-Min Zhang Xiang-Hong Liu Yong Feng Hong-Chao Kou Fan-Jiao Ma wei-dong zeng State Key Laboratory of Solidification Processing Northwestern Polytechnical University Western Superconducting Technologies Co. Ltd. School of Materials Science and Engineering Chang’an University

Development of burn-resistant titanium alloys is the most direct way of mitigating the ignition and propagation of titanium fires in jet engines. WSTi3515S alloy（Ti–35V–15Cr–0.3Si–0.1C） is a new high alloying beta type burn-resistant titanium alloy, belonging to Ti–V–Cr type alloys which have been made significant progress in engineering technology in the past 5 years. The physical properties of WSTi3515S burn-resistant titanium alloy such as the elastic properties and thermal properties were measured and analyzed in different conditions. The results show that both the Young＇s modulus and shear modulus of WSTi3515S alloy decrease slightly with the temperature increasing at the tested temperature range. The Poisson＇s ratio of WSTi3515S alloy is around 0.36. However, the thermal properties such as the specific heat, thermal diffusivity, thermal conductivity and thermal expansion increase with the temperature increasing, which results from the strengthening of lattice heat vibration at elevated temperature. And the room temperature density of WSTi3515S alloy is 5.295 gácm^（-3）.

关键词： Physical properties WSTi3515S alloy Extrusion Burn-resistant