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形变热处理对Cu-Ni-Si合金组织性能的影响

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材料热处理学报 2024年第1期45卷 95-102页

作者：单运启张彦敏张朝民刘爱奎冯江赵世恒皇保欢宋克兴周延军河南科技大学材料科学与工程学院河南洛阳471023 河南省有色金属材料科学与加工技术重点实验室河南洛阳471023 河南省科学院河南郑州450046 河南省先进导体材料重点实验室河南郑州450046 凯美龙精密铜板带(河南)有限公司河南新乡453700

借助扫描电镜、电子万能试验机、维氏硬度计和数字涡流金属电导仪等研究了冷轧变形量和时效对Cu-Ni-Si合金组织与性能的影响。结果表明:冷轧态合金变形量越大,显微组织中晶粒沿着轧制的方向被拉得越长和越扁。当时效温度或时效时间增加... 详细信息

借助扫描电镜、电子万能试验机、维氏硬度计和数字涡流金属电导仪等研究了冷轧变形量和时效对Cu-Ni-Si合金组织与性能的影响。结果表明:冷轧态合金变形量越大,显微组织中晶粒沿着轧制的方向被拉得越长和越扁。当时效温度或时效时间增加到一定程度时,冷变形晶粒发生了回复再结晶,时效时间继续延长再结晶晶粒逐渐长大。冷轧态合金主要以脆性断裂为主,时效态合金以韧性断裂为主。当冷轧变形量为80.0%及经500℃×1 h时效后合金的综合性能最佳,电导率为46.37%IACS,显微硬度为236.14 HV0.1,抗拉强度为638.24 MPa,屈服强度为581.55 MPa,伸长率为5.77%。

关键词： Cu-Ni-Si合金形变热处理显微组织力学性能

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热等静压炉锻造框架仿真分析

真空 2024年第3期61卷 96-99页

作者：宋家兴张功明王颖李忠仁陈鼎苏宁陈博龙沈阳真空技术研究所有限公司辽宁沈阳110042

热等静压炉约束框架,主要在容器加压时起到约束容器两端,承载容器内部产生的轴向力的作用。为了优化框架结构质量及其应力分布情况,利用CAD软件的静力学分析功能,对不同尺寸构件进行仿真计算,得到了最优尺寸参数。结果表明:框架厚度为22... 详细信息

热等静压炉约束框架,主要在容器加压时起到约束容器两端,承载容器内部产生的轴向力的作用。为了优化框架结构质量及其应力分布情况,利用CAD软件的静力学分析功能,对不同尺寸构件进行仿真计算,得到了最优尺寸参数。结果表明:框架厚度为220 mm、宽度为740 mm、端部宽度为390 mm、四角倒角为140 mm时,框架质量和应力分布最优,均可满足设计需求。

关键词：热等静压炉静力学分析锻造框架仿真

维普期刊数据库评论

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维普期刊数据库

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某四缸柴油机曲轴皮带轮性能测试以及分析

内燃机与配件 2024年第2期 1-3页

作者：余明江胡顶王玉凤杨蝶飞宋兴怀昆明云内动力股份有限公司云南昆明650200

为解决某四缸柴油机振动大、曲轴信号质量差以及冷启动困难等问题,本文新设计了带减振功能以及曲轴信号盘的曲轴皮带轮。通过试验对曲轴系进行扭振测试,再采用示波器对曲轴信号质量进行测量和分析,同时验证整机冷启动性能。结果表明不... 详细信息

为解决某四缸柴油机振动大、曲轴信号质量差以及冷启动困难等问题,本文新设计了带减振功能以及曲轴信号盘的曲轴皮带轮。通过试验对曲轴系进行扭振测试,再采用示波器对曲轴信号质量进行测量和分析,同时验证整机冷启动性能。结果表明不同固有频率的橡胶圈对应的曲轴系的扭振强度不同,且新方案能够解决信号丢失的问题。本文分析所得出的结果可为其他机型的扭转振动和信号质量优化提供设计以及试验依据。

关键词：曲轴皮带轮扭转振动信号固有频率冷起动

Downlink scheduling of multiuser MIMO systems with transmit beamforming

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The Journal of China Universities of Posts and Telecommunications 2008年第2期15卷 45-49页

作者： song xing-hua WU Wei-ling Key Laboratory of Information Processing and Intelligent Technology Beijing University of Posts and Telecommunications Beijing 100876 China

This article deals with downlink scheduling for multiuser multiple-input multiple-output （MIMO） systems, where the base station communicates with multiple users simultaneously through transmit beamforming. Most of the existing transmission schemes for multiuser MIMO systems focus on optimizing sum rate performance of the system. The individual quality of service （QoS） requirements （such as packet delay and minimum transmission rate for the data traffic） are rarely considered. In this article, a novel scheduling strategy is proposed, where we try to optimize the global system performance under individual QoS constraints. By performing scheduling into two steps, namely successive user selection and power allocation, the scheduler can achieve efficient resource utilization while maintaining the QoS requirements of all users. Extensive simulations and analysis are given to show the effectiveness of the proposed scheduler.

关键词： power allocation scheduling spatial divisionmultiple access spatial orthogonality transmit beamforming

PbPH5,an H^(+)P-ATPase on the tonoplast,is related to malic acid accumulation in pear fruit

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Journal of Integrative Agriculture 2022年第6期21卷 1645-1657页

作者： song Jun-xing CHEN Ying-can LU Zhao-hui ZHAO Guang-ping WANG Xiao-li ZHAI Rui WANG Zhi-gang YANG Cheng-quan XU Ling-fei College of Horticulture Northwest A&F UniversityYangling 712100P.R.China

Organic acid content is one of the most important factors influencing fruit *** predominant organic acid in most pear cultivars is malic acid,but the mechanism controlling its accumulation remains *** this study,by comparing gene expression levels and organic acid contents,we found that the expression of PbPH5,which encodes a P_(3A)-ATPase,is highly correlated with malic acid accumulation in four different pear species,with correlation coefficients of 0.932**,0.656*,0.900**,and 0.518*(*,P<0.05;**,P<0.01)for Pyrus bretschneideri Rehd.,*** Linn.,*** Nakai.,and *** Maxim.,***,the overexpression of PbPH5 in pear significantly increased the malic acid *** contrast,silencing PbPH5 via RNA interference significantly decreased both its transcript level and the pear fruit malic acid content.A subcellular localization analysis indicated that PbPH5 is located in the ***,a phylogenetic analysis indicated that PbPH5 is a PH5 homolog gene that is clustered with the Petunia hybrida,Malus domestica,and Citrus reticulata *** together,these findings suggest that PbPH5 is a functionally conserved ***,the accumulation of malic acid in pear fruit is at least partly related to changes in the PbPH5 transcription levels.

关键词： pear P3A-ATPase PH5 homolog malic acid accumulation proton pump

Mechanical Properties and Fracture Behavior of Cu-Co-Be Alloy after Plastic Deformation and Heat Treatment

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Journal of Iron and Steel Research International 2016年第9期23卷 933-939页

作者： Yan-jun ZHOU Ke-xing song Jian-dong xing Zhou LI Xiu-hua GUO State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi'an Jiaotong University School of Materials Science and Engineering Henan University of Science and Technology Collaborative Innovation Center of Nonferrous Metals Henan University of Science and Technology School of Materials Science and Engineering Central South University

Mechanical properties and fracture behavior of Cu-0.84Co 0.23Be alloy after plastic deformation and heat treatment were comparatively investigated. Severe plastic deformation by hot extrusion and cold drawing was adopted to induce large plastic strain of Cu 0.84Co-0.23Be alloy. The tensile strength and elongation are up to 476.6 MPa and 18%, respectively. The fractured surface consists of deep dimples and micro voids. Due to the formation of su- persaturated solid solution on the Cu matrix by solution treatment at 950℃ for 1 h, the tensile strength decreased to 271.9 MPa, while the elongation increased to 42%. The fracture morphology is parabolic dimple. Furthermore, the tensile strength increased significantly to 580.2 MPa after aging at 480 ℃ for 4 h. During the aging process, a large number of precipitates formed and distributed on the Cu matrix. The fracture feature of aged specimens with low elongation （4.6%） exhibits an obvious brittle intergranular fracture. It is confirmed that the mechanical properties and fracture behavior are dominated by the microstrueture characteristics of Cu-0.84Co 0.23Be alloy after plastic de- formation and heat treatment. In addition, the fracture behavior at 450 ℃ of aged Cu-0.84Co 0.23Be alloy was also studied. The tensile strength and elongation are 383.6 MPa and 11.2%, respectively. The fractured morphologies are mainly candy-shaped with partial parabolic dimples and equiaxed dimples. The fracture mode is multi mixed mechanism that brittle intergranular fracture plays a dominant role and ductile fracture is secondary.

关键词： Cu-Co-Be alloy heat treatment mechanical property fracture behavior plastic deformation

High temperature treatment induced production of unreduced 2n pollen in Camellia oleifera

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Horticultural Plant Journal 2024年第3期10卷 879-896页

作者： Hongda Deng Xiaoyu Zhang song Sheng Yuxun Huang Ziqi Ye Tongyue Zhang xing Liu Zhiqiang Han The Laboratory of Forestry Genetics Central South University of Forestry and TechnologyChangshaHunan 410004China Yuelushan Laboratory ChangshaHunan 410128China Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees of Ministry of Education Central South University of Forestry and TechnologyChangshaHunan 410004China National Forest and Seedling Workstation of Hunan Province The Forestry Department of Hunan ProvinceChangshaHunan 410004China

Unreduced gametes through chromosome doubling play a major role in the process of plant *** previous work confirmed that Camellia oleifera can produce natural 2n pollen,and it is possible to induce the 2n pollen formation by high temperature *** study focused on the optimization of the 2n pollen induction technique and the mechanisms of high temperature-induced2n pollen formation in *** found that the optimal protocol for inducing 2n pollen via high temperature was to perform 45℃with4 h at the prophaseⅠstage of the pollen mother cells(PMCs).Meanwhile,high temperature significantly decreased the yield and fertility of2n *** the observation of meiosis,abnormal chromosome and cytological behaviour was discovered under high-temperature treatment,and we confirmed that the formation of 2n pollen is caused by abnormal cell *** on weighted gene co-expression network analysis,fifteen hub genes related to cell cycle control were *** male flower buds were exposed to heat shock,polygalacturonase gene(CoPGX3)was significantly *** inferred that high temperature causes the CoPGX3 gene to be overexpressed and that CoPGX3 is redistributed into the cytosol where it degrades cytoplasmic pectin,which leads to an abnormal cell ***,abnormal cytokinesis resulted in the formation of dyads and triads,and PMCs divided to produce 2n *** findings provide new insights into the mechanism of 2n pollen induced by high temperature in a woody plant and lay a foundation for further ploidy breeding of ***.

关键词： Camellia oleifera Pollen mother cells(PMCs) High temperature Meiosis 2n pollen CoPGX3

Bayesian inference for ammunition demand based on Gompertz distribution

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Journal of Systems Engineering and Electronics 2020年第3期31卷 567-577页

作者： ZHAO Rudong SHI Xianming WANG Qian SU Xiaobo song xing Department of Equipment Command and Management Shijiazhuang CampusArmy Engineering UniversityShijiazhuang 050003China Unit 73127 of the PLA Fuzhou 350503China The Ninth Comprehensive Training Base of Army Zhangjiakou 075000China Army Infantry College of the PLA Shijiazhuang 050003China Unit 68303 of the PLA Golmud 816000China

Aiming at the problem that the consumption data of new ammunition is less and the demand is difficult to predict,combined with the law of ammunition consumption under different damage grades,a Bayesian inference method for ammunition demand based on Gompertz distribution is *** Bayesian inference model based on Gompertz distribution is constructed,and the system contribution degree is introduced to determine the weight of the multi-source *** the case where the prior distribution is known and the distribution of the field data is unknown,the consistency test is performed on the prior information,and the consistency test problem is transformed into the goodness of the fit test *** the Bayesian inference is solved by the Markov chain-Monte Carlo(MCMC)method,and the ammunition demand under different damage grades is *** example verifies the accuracy of this method and solves the problem of ammunition demand prediction in the case of insufficient samples.

关键词： ammunition demand prediction Bayesian inference Gompertz distribution system contribution Markov chain-Monte Carlo(MCMC)method

Lymphatic vessel:origin,heterogeneity,biological functions,and therapeutic targets

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Signal Transduction and Targeted Therapy 2024年第2期9卷 442-478页

作者： Zhaoliang Hu Xushi Zhao Zhonghua Wu Bicheng Qu Minxian Yuan Yanan xing Yongxi song Zhenning Wang Department of Surgical Oncology and General Surgery The First Hospital of China Medical UniversityKey Laboratory of Precision Diagnosis and Treatment of Gastrointestinal Tumors(China Medical University)Ministry of Education155 North Nanjing StreetHeping DistrictShenyang 110001China

Lymphatic vessels,comprising the secondary circulatory system in human body,play a multifaceted role in maintaining homeostasis among various tissues and *** are tasked with a serious of responsibilities,including the regulation of lymph absorption and transport,the orchestration of immune surveillance and *** vessel development undergoes a series of sophisticated regulatory signaling pathways governing heterogeneous-origin cell populations stepwise to assemble into the highly specialized lymphatic vessel ***,as defined by new lymphatic vessels sprouting from preexisting lymphatic vessels/embryonic veins,is the main developmental mechanism underlying the formation and expansion of lymphatic vessel networks in an ***,abnormal lymphangiogenesis could be observed in many pathological conditions and has a close relationship with the development and progression of various *** studies have revealed a set of lymphangiogenic factors and cascades that may serve as the potential targets for regulating abnormal lymphangiogenesis,to further modulate the progression of ***,an increasing number of clinical trials have demonstrated the promising interventions and showed the feasibility of currently available treatments for future clinical *** lymphangiogenic promoters or inhibitors not only directly regulates abnormal lymphangiogenesis,but improves the efficacy of diverse *** conclusion,we present a comprehensive overview of lymphatic vessel development and physiological functions,and describe the critical involvement of abnormal lymphangiogenesis in multiple ***,we summarize the targeting therapeutic values of abnormal lymphangiogenesis,providing novel perspectives for treatment strategy of multiple human diseases.

关键词： therapeutic origin specialized