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“结构性组织”思维下的教师培训项目管理专业化建设
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作者 戴礼章 刘令军 《教师》 2018年第32期91-92,共2页
“结构性组织”思维下的教师培训项目管理,这个命题包含了两个方面:第一是思维,即人的思考活动,强调的是“思维导图”意识;第二是管理,这种管理机制是宁乡市教师进修学校的一种管理创新,它的基础和保障是进行三项“专业化建设”:一是... “结构性组织”思维下的教师培训项目管理,这个命题包含了两个方面:第一是思维,即人的思考活动,强调的是“思维导图”意识;第二是管理,这种管理机制是宁乡市教师进修学校的一种管理创新,它的基础和保障是进行三项“专业化建设”:一是培训者人才队伍的专业化建设,二是培训系统流程的专业化建设,三是培训评估检测系统的专业化建设. 展开更多
关键词 教师培训 结构性组织 项目管理 专业化建设
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试论信息化、网络化海关组织的结构性调整 被引量:1
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作者 薛金楼 《科技管理研究》 CSSCI 北大核心 2008年第2期238-241,共4页
传统的层级管理模式对于维护海关垂直领导体制发挥了重要作用。但随着信息网络技术的快速发展,海关传统的层级结构赖以生存的外部经济、社会环境已发生了巨大的改变,海关现代化建设对其组织结构提出了挑战,须运用现代管理理念与信息技... 传统的层级管理模式对于维护海关垂直领导体制发挥了重要作用。但随着信息网络技术的快速发展,海关传统的层级结构赖以生存的外部经济、社会环境已发生了巨大的改变,海关现代化建设对其组织结构提出了挑战,须运用现代管理理念与信息技术改造现行的层级组织管理模式,构建动态网络组织,用网络结构优势来补充层级结构的不足,提高管理效率。 展开更多
关键词 海关 信息化 网络化 组织结构性调整
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公司组织结构引发的中小型企业管理学思考
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作者 李莉 《大众商务(下半月)》 2010年第2期104-104,共1页
我国中小型企业正迎来发展新时期,如何在发展壮大的同时保持组织生命和活力成为了业界关注和思考的焦点。本文以A公司发展中出现的组织结构问题为例,探讨具有可行性的问题解决方案。
关键词 组织结构 组织结构性问题 组织结构性问题 组织文化 管理分权
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论组织成本的历史性发展 被引量:1
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作者 张世和 《中共山西省委党校省直分校学报》 2006年第1期45-47,共3页
组织成本相对来讲是一个受各种因素影响较大的成本构成,由于组织组织成本与其它方面的成本相比较有其独特之处,因此,我们应当从历史与未来发展趋势以及结构的角度对其进行研究。
关键词 组织成本 领导性组织成本 结构性组织成本 历史性发展
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Microstructure and mechanical properties of TiAl-based alloy prepared by double mechanical milling and spark plasma sintering 被引量:3
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作者 肖树龙 徐丽娟 +1 位作者 陈玉勇 于宏宝 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第5期1086-1091,共6页
A fine-grained TiAl alloy with a composition of Ti-45Al-2Cr-2Nb-1B-0.5Ta-0.225Y (mole fraction, %) was prepared by double mechanical milling(DMM) and spark plasma sintering(SPS). The relationship among sintering... A fine-grained TiAl alloy with a composition of Ti-45Al-2Cr-2Nb-1B-0.5Ta-0.225Y (mole fraction, %) was prepared by double mechanical milling(DMM) and spark plasma sintering(SPS). The relationship among sintering temperature, microstructure and mechanical properties was studied. The results show that the morphology of double mechanical milled powder is regular with size in the range of 20-40 μm and mainly composed of TiAl and Ti3Al phases. The main phase TiAl and few phases Ti3Al, Ti2Al and TiB2 were observed in the SPSed alloys. For samples sintered at 900 ℃ the equiaxed crystal grain microstructure is achieved with size in the range of 100-200 nm. With increasing the SPS temperature from 900 ℃to 1000 ℃ the size of equiaxed crystal grain obviously increases, the microhardness decreases from HV658 to HV616, and the bending strength decreases from 781 MPa to 652 MPa. In the meantime, the compression fracture strength also decreases from 2769 MPa to 2669 MPa, and the strain to fracture in compression increases from 11.69% to 17.76%. On the base of analysis of fractographies, it shows that the compression fracture transform of the SPSed alloys is intergranular rupture. 展开更多
关键词 TiAl-based alloys mechanical alloying spark plasma sintering MICROSTRUCTURE mechanical properties
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Microstructure and mechanical properties of Mg-Gd-Y-Zr alloy cast by metal mould and lost foam casting 被引量:15
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作者 李吉林 陈荣石 柯伟 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第4期761-766,共6页
The microstructure and mechanical properties of Mg-10.1Gd-3.74Y-0.25Zr (mass fraction, %) alloy (GW104 alloy) cast by metal mould casting (MMC) and lost foam casting (LFC) were evaluated, respectively. It is r... The microstructure and mechanical properties of Mg-10.1Gd-3.74Y-0.25Zr (mass fraction, %) alloy (GW104 alloy) cast by metal mould casting (MMC) and lost foam casting (LFC) were evaluated, respectively. It is revealed that different forming modes do not influence the phase composition of as-cast alloy. In the as-cast specimens, the microstructures are similar and composed of α-Mg solid solution, eutectic compound of α-Mg+Mg 24 (Gd, Y) 5 and cuboid-shaped Mg 5 (Gd, Y) phase; whereas the average grain size of the alloy produced by metal mould casting is smaller than that by lost foam casting. The eutectic compound of the alloy is completely dissolved after solution treatment at 525 ℃for 6 h, while the Mg 5 (Gd, Y) phase still exists after solution treatment. After peak-ageing, the lost foam cast alloy exhibits the maximum ultimate tensile strength of 285 MPa, and metal mould cast specimen 325 MPa at room temperature, while the tensile yield strengths of them are comparable. It can be concluded that GW104 alloy cast by lost foam casting possesses similar microstructure and evidently lower mechanical strength compared with metal mould cast alloy, due to slow solidification rate and proneness to form shrinkage porosities during lost foam casting process. 展开更多
关键词 Mg-Gd-Y-Zr alloy lost foam casting metal mould casting MICROSTRUCTURE mechanical property
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Quench sensitivity of 6351 aluminum alloy 被引量:2
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作者 李慎兰 黄志其 +2 位作者 陈维平 刘志铭 戚文军 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第1期46-52,共7页
The quench sensitivity of 6351 alloy was determined by the time temperature-transformation(TTT) curves and time temperature-property(TTP) curves by an interrupted quench technique with measurement of as-aged hardn... The quench sensitivity of 6351 alloy was determined by the time temperature-transformation(TTT) curves and time temperature-property(TTP) curves by an interrupted quench technique with measurement of as-aged hardness and as-quenched electro-conductivity.The microstructure transformation during isothermal treatment was studied by the transmission electron microscopy(TEM) and Avrami equation.The results showed that the electro-conductivity of the 6351 alloy increased and the hardness decreased with prolonging the holding time at a certain isothermal temperature.The TEM observation indicated that the supersaturated solid solution decomposed and needles β″ precipitated at the initial stage of isothermal holding.With the prolongation of holding time at the nose temperature,rod β' and plate β phases formed.The isothermal transformation rate at 360℃ was the fastest,and became slow at 280℃ and reached the slowest at 440℃.The nose temperatures of the TTT and TTP curves were about 360℃ and the high quench sensitive temperature range was 230 430℃.The quench factor analysis indicated that the cooling rate should be more than 15℃/s in the quench sensitive areas in order to get optimal mechanical properties. 展开更多
关键词 6351 alloy quench sensitivity MICROSTRUCTURE cooling rate quench factor analysis TTT curve TTP curve
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Microstructure stability of Ti_2Al N/Ti-48Al-2Cr-2Nb composite at 900 °C 被引量:1
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作者 刘懿文 胡锐 张铁邦 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第2期423-430,共8页
Microstructure stability of in situ synthesized Ti2AlN/Ti-48Al-2Cr-2Nb composite during aging at 900 ℃ was investigated by XRD, OM and TEM, and the unreinforced Ti-48Al-2Cr-2Nb alloy was also examined for comparison.... Microstructure stability of in situ synthesized Ti2AlN/Ti-48Al-2Cr-2Nb composite during aging at 900 ℃ was investigated by XRD, OM and TEM, and the unreinforced Ti-48Al-2Cr-2Nb alloy was also examined for comparison. The result showed that in the TiAl alloy,α2 lamellae thinned and were broken down, and became discontinuous with increasing aging time. The decomposition ofα2 lamella toγ which was characterized by parallel decomposition and breakdown ofα2 lamellae led to the degradation of the lamellar structure. While in the composite, lamellar structure remained relatively stable even after aging at 900 ℃ for 100 h. No breakdown ofα2 lamellae except parallel decomposition and precipitation of fine nitride particles was observed. The better microstructural stability of the composite was mainly attributed to the precipitation of Ti2AlN particles at theα2/γ interface which played an important role in retarding the coarsening of lamellar microstructure in the matrix of composite. 展开更多
关键词 TiAl composite Ti2AlN microstructure stability lamellar structure PRECIPITATION
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Effects of four regulating-intestine prescriptions on pathology and ultrastructure of colon tissue in rats with ulcerative colitis 被引量:19
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作者 Heng Fan Ming-Yi Qiu +3 位作者 Jia-Jun Mei Guan-Xin Shen Song-Lin Liu Rui Chen 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第31期4800-4806,共7页
AIM: To observe different histomorphologic changes of ulcerative colitis (UC) rats that were treated with four regulating-intestine prescriptions (FRIP), to investigate the curative effects of FRIP and to analyze thei... AIM: To observe different histomorphologic changes of ulcerative colitis (UC) rats that were treated with four regulating-intestine prescriptions (FRIP), to investigate the curative effects of FRIP and to analyze their treatment mechanism.METHODS: The UC rat model was made by the method of 2,4-dinitro chloro benzene (DNCB) immunity and acetic acid local enema. Ninety-eight SD rats were randomly divided into seven groups, namely, the normal control group, model group, salicylazosulfapyridine (SASP) group,Wumeiwan (WMW) group, Baitouwengtang (BTWT) group,Senglingbaishusan (SLBSS) group, and Tongxieyaofang (TXYF) group. Each group had 14 rats (with equal ratio of male and female). The six animal model groups of UC-SASP, TXYF, WMW, BTWT, SLBSS, TXYF-were treated by distilled water except the normal control group. Changes of the rat's general conditions after treatment were respectively observed, the colon tissue damage scores were given out, the pathology of colonic mucosa and changes of ultrastructure were analyzed.RESULTS: Different pathological changes on histology were shown after treatment by FRIP. The colon tissue damage score in model group was higher than that of FRIP groups and SASP group (q = 4.59, 4.77, P<0.05 or q = 5.48,6.25, 5.97, P<0.01). The scores of WMW group, BTWT group and SLBSS group were lower than that of SASP (q = 4.13, P<0.05 or q = 5.31, 5.12, P<0.01). There was no remarkable difference between the damage score of TXYF group and SASP group (q = 3.75, P>0.05). In addition, some apoptosis cells were found in the pathologic control group.CONCLUSION: The model made with DNCB and acetic acid was successful, and FRIP had better curative effect and WMW was the best curative effect, BTW, SLBSS and TXYF were similar to SASP, and we discovered that apoptosis was possibly related to UC. 展开更多
关键词 Ulcerative colitis TCM therapy Experimentalresearch PATHOLOGY ULTRASTRUCTURE Apoptosis
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Microstructure and tensile properties of rapid-cooling friction-stir-welded AZ31B Mg alloy along thickness direction 被引量:7
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作者 Nan XU Wei-da ZHANG +3 位作者 Si-qi CAI Yue ZHUO Qi-ning SONG Ye-feng BAO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第12期3254-3262,共9页
Rapid-cooling friction-stir-welding(FSW)was used to join AZ31B magnesium alloy plates of 6 mm in thickness.The microstructure and mechanical properties in thickness direction were carefully investigated with electron ... Rapid-cooling friction-stir-welding(FSW)was used to join AZ31B magnesium alloy plates of 6 mm in thickness.The microstructure and mechanical properties in thickness direction were carefully investigated with electron backscattered diffractometer,and transmission electron microscope.The obtained results showed that ultrafine grains with high dislocation density were obtained in the top region of the weld due to liquid CO2 cooling.A large number of{1012}twins and second-phase particles were also induced in these refined grains.The basal texture intensity was significantly reduced due to the appearance of{1012}twins.The top region showed the higher strength and elongation compared with the bottom region,and the welding efficiency reached 93%.This work provided a simple and efficient strategy for manufacturing a gradient structure in the FSW Mg alloy joint. 展开更多
关键词 friction stir welding magnesium alloy RECRYSTALLIZATION texture MICROSTRUCTURE mechanical properties
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Isozyme Analysis of Spotted Halibut Verasper variegatus Temminck et Schlegel 被引量:5
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作者 LIUManhong GAOTianxiang +1 位作者 ZHANGXiumei CHENSiqing 《Journal of Ocean University of China》 SCIE CAS 2005年第1期43-48,共6页
To investigate the tissue-specificities of isozymes and the genetic structureof wild spotted halibut ( Verasper variegatus) population, horizontal starch gel electrophoresiswas performed on 45 individuals collected in... To investigate the tissue-specificities of isozymes and the genetic structureof wild spotted halibut ( Verasper variegatus) population, horizontal starch gel electrophoresiswas performed on 45 individuals collected in part of the Yellow Sea. The performances of 17 isozymesin 8 kinds of tissues or organs were screened preliminarily in a TC-7.0 buffer system. The resultsshowed that the screened isozymes displayed remarkable tissue-specificities. Finally, 14 enzymes(AAT, ADH, EST, OPI, G3PDH, IDHP, LAP, LDH, MDH, MPI, PGDH, PGM, SDH and SOD) and 4 kinds of tissues(eye, skeleton muscle, liver and heart) were selected for genetic analysis. Fourteen isozymes areencoded by 20 loci, and 9 of them are polymorphic. The polymorphic loci are AAT-1~*, GPI-2~*,G3PDH~*, IDHP-1~*, LDH~*, MPI~*, PGM-1~*. PGM-2~* and SDH~*, and the proportion of polymorphic lociis 0.4500 (P_(0.99)) ? The mean values of observed and expected heterozygosities are 0.0278and 0.0265, respectively and the average effective number of alleles is 1.0675. 展开更多
关键词 verasper variegatus ISOZYME TISSUE-SPECIFICITY genetic structure
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Sol-gel auto-combustion synthesis of K_xNa_(1-x)NbO_3 nanopowders and ceramics: Dielectric and piezoelectric properties 被引量:1
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作者 Hua-lei CHENG Jian XIAO +3 位作者 Peng GAO Yun-yun YAN Shuan-ping GAO Hong-liang DU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第9期1801-1807,共7页
The KxNa1-xNbO3 nanopowders with cubic-like morphology and an average size of about 50 nm were synthesized by sol-gel auto-combustion method.And then,the ceramics were prepared and the phase transition,microstructure ... The KxNa1-xNbO3 nanopowders with cubic-like morphology and an average size of about 50 nm were synthesized by sol-gel auto-combustion method.And then,the ceramics were prepared and the phase transition,microstructure and electrical properties of the KxNa1-xNbO3 ceramics were investigated.Pure perovskite phases of the KxNa1-xNbO3 ceramics were confirmed by XRD patterns and the K0.50Na0.50NbO3 ceramics show the coexistence of orthorhombic and monoclinic structures.SEM micrographs show that all samples have bimodal grain size distributions and the number of the small grains decrease with increasing K+content in the bimodal grain size distribution system.The K0.50Na0.50NbO3 ceramics with the uniform grain size and the maximum density show excellent electrical properties withεr=467.40,tanδ=0.020,d33=128 pC/N and kp=0.32 at the room temperature,demonstrating that the properties of the K0.50Na0.50NbO3 powers prepared by sol-gel auto-combustion are excellent and the ceramics are promising lead-free piezoelectric materials. 展开更多
关键词 sol-gel auto-combustion KxNa1-xNbO3 phase transition MICROSTRUCTURE electrical properties
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Microstructure and photocatalytic activity of Ni-doped ZnS nanorods prepared by hydrothermal method 被引量:4
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作者 Wen-hua ZHAO Zhi-qiang WEI +3 位作者 Xiao-juan WU Xu-dong ZHANG Li ZHANG Xuan WANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第1期157-164,共8页
Pure ZnS and Ni^2+-doped ZnS nanorods (Zn1-xNixS, x=0, 0.01, 0.03, 0.05 and 0.07, mole fraction,%) were synthesized by hydrothermal method. The effects of Ni2+ doping on the phase-structure, morphology, elemental comp... Pure ZnS and Ni^2+-doped ZnS nanorods (Zn1-xNixS, x=0, 0.01, 0.03, 0.05 and 0.07, mole fraction,%) were synthesized by hydrothermal method. The effects of Ni2+ doping on the phase-structure, morphology, elemental composition and optical properties of the samples were investigated by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), X-ray energy dispersive spectrometry (EDS) and ultraviolet–visible spectroscopy (UV-Vis), respectively. The photocatalytic activity of Zn1-xNixS nanorods was evaluated by the photodegradation of organic dyes Rhodamine B (RhB) in aqueous solution under UV light irradiation. The results show that all samples exhibit wurtzite structure with good crystallization. The morphologies are one-dimensional nanorods with good dispersion, and the distortion of the lattice constant occurs. The band gap of Zn1-xNixS samples is smaller than that of pure ZnS, thus red shift occurs. Ni^2+-doped ZnS nanocrystals can enhance photocatalytic activities for the photodegradation of RhB. Especially, Zn0.97Ni0.03S sample exhibits better photocatalytic performance and photocatalytic stability for the decomposition of RhB. 展开更多
关键词 Zn1-xNixS nanorods PHASE-STRUCTURE MICROSTRUCTURE photocatalytic activity hydrothermal method
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Development of a pentaethylenehexamine-modified solid support adsorbent for CO_2 capture from model flue gas 被引量:5
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作者 韦力 靖宇 +1 位作者 高正明 王运东 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第2期366-371,共6页
A novel solid support adsorbent for CO2capture was developed by loading pentaethylenehexamine(PEHA)on commercially available mesoporous molecular sieve MCM-41 using wet impregnation method.MCM-41 samples before and af... A novel solid support adsorbent for CO2capture was developed by loading pentaethylenehexamine(PEHA)on commercially available mesoporous molecular sieve MCM-41 using wet impregnation method.MCM-41 samples before and after PEHA loading were characterized by X-ray powder diffraction,N2adsorption/desorption,thermal gravimetric analysis and scanning electron microscope to investigate the textural and thermo-physical properties.CO2adsorption performance was evaluated in a fixed bed adsorption system.Results indicated that the structure of MCM-41 was preserved after loading PEHA.Surface area and total pore volume of PEHA loaded MCM-41 decreased with the increase of loading.The working adsorption capacity of CO2could be significantly improved at 60%of PEHA loading and 75°C.The effect of the height of adsorbent bed was investigated and the best working adsorption capacity for MCM-41-PEHA-60 reached 165 mg·(g adsorbent)-1at 75°C.Adsorption/desorption circle showed that the CO2working adsorption capacity of MCM-41-PEHA kept stable. 展开更多
关键词 CO2adsorption Pentaethylenehexamine MCM-41 molecular sieve CO2adsorbent
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Die sinter bonding in air using copper formate preform for formation of full-density bondline 被引量:3
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作者 Yun-Ju LEE Jong-Hyun LEE 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第6期1717-1728,共12页
Pressure-assisted sinter bonding was performed in air at 250−350℃ using a preform comprising copper formate particles to form a bondline that is sustainable at high temperatures.H2 and CO generated concurrently by th... Pressure-assisted sinter bonding was performed in air at 250−350℃ using a preform comprising copper formate particles to form a bondline that is sustainable at high temperatures.H2 and CO generated concurrently by the pyrolysis of copper formate at 210℃ during the sinter bonding removed the native oxide and other oxides grown on bulk Cu finishes,enabling interface bonding.Moreover,Cu produced in situ by the reduction of Cu(II)accelerated the sinter bonding.Consequently,the bonding achieved at 300−350℃ under 5 MPa exhibited sufficient shear strength of 20.0−31.5 MPa after 180−300 min of sinter bonding.In addition,an increase in pressure to 10 MPa resulted in shear strength of 21.9 MPa after an extremely short time of 30 s at 250℃,and a near-full-density bondline was achieved after 300 s.The obtained results indicate the promising potential of the preform comprising copper formate particles for high-speed sinter bonding. 展开更多
关键词 structural materials microstructure mechanical properties copper formate preform sinter bonding PYROLYSIS
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Microstructure and mechanical properties of new metastable β type titanium alloy 被引量:3
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作者 周中波 费跃 +6 位作者 赖敏杰 寇宏超 常辉 商国强 朱知寿 李金山 周廉 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第12期2253-2258,共6页
A new metastable β type titanium alloy called TB-13 with the combination of excellent strength and ductility was developed successfully.In order to develop a perspective on this new alloy,the influence of several com... A new metastable β type titanium alloy called TB-13 with the combination of excellent strength and ductility was developed successfully.In order to develop a perspective on this new alloy,the influence of several commonly used heat treatments on the microstructure and properties was studied.In solution-treated and quenched samples,a low-temperature aging at 480°C results in the precipitation of finerαphase.The precipitation of coarserαphase plate at higher aging temperature(560°C)leads to the increase of tensile ductility but reduction of strength.During low-temperature aging at 300°C,quite homogeneous distribution of fine isothermalωphase particles was found.The isothermalωphase provides nucleation sites forαphase during two-step aging process and makesαphase extremely fine and disperse uniformly in β matrix.Thus,TB-13 alloy is strengthened and its mechanical properties are improved. 展开更多
关键词 metastable β titanium heat treatment MICROSTRUCTURE mechanical property
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Robust Background Subtraction Method via Low-Rank and Structured Sparse Decomposition 被引量:1
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作者 Minsheng Ma Ruimin Hu +2 位作者 Shihong Chen Jing Xiao Zhongyuan Wang 《China Communications》 SCIE CSCD 2018年第7期156-167,共12页
Background subtraction is a challenging problem in surveillance scenes. Although the low-rank and sparse decomposition(LRSD) methods offer an appropriate framework for background modeling, they fail to account for ima... Background subtraction is a challenging problem in surveillance scenes. Although the low-rank and sparse decomposition(LRSD) methods offer an appropriate framework for background modeling, they fail to account for image's local structure, which is favorable for this problem. Based on this, we propose a background subtraction method via low-rank and SILTP-based structured sparse decomposition, named LRSSD. In this method, a novel SILTP-inducing sparsity norm is introduced to enhance the structured presentation of the foreground region. As an assistance, saliency detection is employed to render a rough shape and location of foreground. The final refined foreground is decided jointly by sparse component and attention map. Experimental results on different datasets show its superiority over the competing methods, especially under noise and changing illumination scenarios. 展开更多
关键词 background subtraction LRSD structured sparse SILTP
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Influence of long-term isothermal aging on microstructure and creep rupture properties of Ni-base superalloy M4706 被引量:1
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作者 DUAN Yu-hao ZHANG Peng +4 位作者 LI Jiao LI Bo SONG Xiao-long GONG Xiu-fang YANG Gong-xian 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第2期325-333,共9页
After a standard heat treatment,the microstructural evolution with time during isothermal aging at 850°C and its effect on the creep rupture properties of the Ni-base superalloy M4706 at 870°C and 370 MPa ar... After a standard heat treatment,the microstructural evolution with time during isothermal aging at 850°C and its effect on the creep rupture properties of the Ni-base superalloy M4706 at 870°C and 370 MPa are investigated.It is found that as the aging time increases from 0 to 5000 h,the average diameter of coarseγ′increases from 241 to 484 nm,and the distribution of the carbides at grain boundaries changes from discontinuous to continuous.Moreover,experimental observations on the microstructures of all the crept specimens reveal that dislocation bypassing controls the creep deformation.Thus,it is concluded that the transitions in the microstructures result in the degeneration of the creep rupture properties of the experimental alloy with aging time. 展开更多
关键词 Ni-base superalloy isothermal aging MICROSTRUCTURE creep rupture properties
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Microstructure and mechanical properties of ZA62 based magnesium alloys with calcium addition 被引量:1
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作者 万晓峰 孙扬善 +2 位作者 薛烽 白晶 陶卫建 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第5期757-762,共6页
As-cast microstructure and mechanical properties of Mg-6Zn-2Al-0.3Mn (ZA62) alloys with calcium addition were investigated.The as-cast microstructure of the base alloy ZA62 consists of the α-Mg matrix and eutectic ph... As-cast microstructure and mechanical properties of Mg-6Zn-2Al-0.3Mn (ZA62) alloys with calcium addition were investigated.The as-cast microstructure of the base alloy ZA62 consists of the α-Mg matrix and eutectic phase Mg51Zn20.The Mg51Zn20 eutectic was gradually replaced by MgZn phase and Mg32(Al,Zn)49 phase when calcium is added into the base alloy.Further addition of calcium leads to the increase of grain boundary phases and formation of a new quaternary Mg-Zn-Al-Ca eutectic compound.In comparison with the base alloy,the increase of calcium addition to the base alloy results in the reduction of both strength and ductility at ambient temperature,but increase at elevated temperatures due to the thermal stability of Ca-containing phases.At elevated temperatures,the creep resistance of ZA62 based alloys containing calcium is significantly higher than that of AZ91 which is the most commonly used magnesium alloy. 展开更多
关键词 magnesium alloys ZA62 alloys calcium creep properties
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Effects of mechanical activation on the structural changes and microstructural characteristics of the components of ferruginous quartzite beneficiation tailings 被引量:2
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作者 Ermolovich E.A. Ermolovich O.V. 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第6期1043-1049,共7页
The effects of mechanical activation in a planetary mill on the structural changes and microstructural characteristics of the components of ferruginous quartzite beneficiation railings generated by wet magnetic separa... The effects of mechanical activation in a planetary mill on the structural changes and microstructural characteristics of the components of ferruginous quartzite beneficiation railings generated by wet magnetic separation process were studied using X-ray and laser diffraction methods. The results revealed the relationship between variations in the mean particle size of activated powders and the milling time. The crystallite size, microstrain, lattice parameters and unit cell volumes were determined for different milling times in powder samples of quartz, hematite, dolomite, and magnetite from the beneficiation tailings. The main trends in the variation of the crystallite size of quartz, hematite, dolomite, and magnetite as a function mean particle size of powder samples were revealed. Changes in the particle shape as a function of the activation time was also investigated. 展开更多
关键词 Ferruginous quartzite beneficiation tailings Mechanical activation Crystallites Planetary mill Microstructure Structural changes
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