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Chinese Journal of Mechanical Engineering 2024年第4期37卷 23-49页

作者： Heng Tang jiaxiang xu Bin Guo Yansong Xie Yalong Sun Yanjun Lu Yong Tang Guangdong Provincial Key Laboratory of Micro/Nano Optomechatronics Engineering College of Mechatronics and Control EngineeringShenzhen UniversityShenzhen 518000China School of Mechanical and Power Engineering Zhengzhou UniversityZhengzhou 450001China

Titanium and its alloys have been widely applied in many biomedical fields because of its excellent mechanical properties,corrosion resistance and good ***,problems such as rejection,shedding and infection will occur after titanium alloy implantation due to the low biological activity of titanium alloy *** structures with specific functions,which can enhance osseointegration and antibacterial properties,are fabricated on the surface of titanium implants to improve the biological activity between the titanium implants and human *** paper presents a comprehensive review of recent developments and applications of surface functional structure in titanium and titanium alloy *** applications of surface functional structure on different titanium and titanium alloy implants are introduced,and their manufacturing technologies are summarized and ***,the fabrication of various surface functional structures used for titanium and titanium alloy implants is reviewed and analyzed in ***,the challenges affecting the development of surface functional structures applied in titanium and titanium alloy implants are outlined,and recommendations for future research are presented.

关键词： Surface functional structure Titanium implant Manufacturing technology Bioactivity

Solid-liquid flow characteristics and sticking-force analysis of valve-core fitting clearance

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2023年第12期24卷 1096-1105页

作者： Jin-yuan QIAN jiaxiang xu Fengping ZHONG Zhenhao LIN Tingfeng HUA Zhijiang JIN Institute of Process Equipment College of Energy EngineeringZhejiang UniversityHangzhou 310027China Zhejiang Academy of Special Equipment Science Hangzhou 310009China Institute of Wenzhou Zhejiang UniversityWenzhou 325036China

External contamination particles or wear particles corroded by a valve body are mixed into the fluid. As a result, when the fluid enters the fitting clearance of the valve core, it can cause an increase in resistance and lead to sticking failure of the valve core. This paper analyzes solid-liquid flow characteristics in fitting clearances and valve-core sticking based on the Euler-Euler model, using a typical hydraulic valve as an example. The impact of particle concentration and diameter on flow characteristics and valve-core sticking force was analyzed. The highest volume fraction of particles was in the pressureequalizing groove(PEG), with peak values increasing as the particle diameter increased. The sticking force increased with increasing particle concentration. When the particle diameter was 12 μm, the sticking force was the largest, making this the sensitive particle diameter. Particle distribution and valve-core sticking force were compared for oval, rectangular, and triangular PEGs. The fluid-deflection angles in oval and rectangular PEGs were larger, and their values were 32.83° and 39.15°, respectively. The fluid-deflection angle in the triangular PEG was relatively small, less than 50% that of the oval or rectangular PEGs. The particle-volume-fraction peaks in oval, rectangular, and triangular PEGs were 0.0317, 0.0316, and 0.0312, respectively. The sticking forces of oval, rectangular, and triangular PEGs were 4.796, 4.802, and 4.757 N, respectively when the particle diameter was 12 μm. This work provides a reference for design and research aimed at reducing valve-core sticking.

关键词： Solid-liquid flow characteristics Valve core Sticking force Euler-Euler model

Time-Optimal Trajectory Planning of Industrial Robot based on Improved Particle Swarm Optimization Algorithm

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Time-Optimal Trajectory Planning of Industrial Robot based o...

第三十九届中国控制会议

作者： Buhai Shi jiaxiang xu School of Automation Science and Engineering South China University of Technology

Industrial robot has been widely used since the development of manufacturing. A time-optimal trajectory planning for industrial robot can help to save energy and improve efficiency. This paper proposed a new trajectory planning method based on improved particle swarm optimization. Golden section method is used to find the maximum of velocity, acceleration and *** to derivative method, way used Golden section method can find the maximum more quickly. Roll-back technology is introduced to ensure the diversity of particle swarm, which makes sure that the search ability will not be weaken by the reduction of number of particles. An improved particle swarm optimization with variable learning factor is used to search the global best solution. The results of simulation show that the proposed trajectory planning method can generate a time-optimal trajectory for industrial robot.

关键词： B-spline Time optimal Trajectory planning Particle swarm optimization

来源： cnki会议评论

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临近空间目标智能拦截概念技术研究

战术导弹技术 2017年第3期 29-33页

作者：徐佳祥中国空空导弹研究院洛阳471009

基于对智能技术应用的研究,对临近空间高超声速目标拦截的问题进行了概念探讨,并结合精确制导武器的工作特点和设计约束,提出了目标智能拦截功能组成的逻辑结构。同时,从物理概念的角度对智能波束形成、高超声速的多谱勒速度补偿技术、... 详细信息

基于对智能技术应用的研究,对临近空间高超声速目标拦截的问题进行了概念探讨,并结合精确制导武器的工作特点和设计约束,提出了目标智能拦截功能组成的逻辑结构。同时,从物理概念的角度对智能波束形成、高超声速的多谱勒速度补偿技术、跟踪的数据相关处理技术、制导律设计等智能拦截基础技术进行了一定的分析。

关键词：临近空间高超声速技术精确制导智能拦截

高温高压Y型截止阀组内流特性及流道结构改进研究

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机电工程 2025年第1期42卷 1-10页

作者：马哲辉吴斌彬李文庆许家祥金志江钱锦远浙江大学化工机械研究所浙江杭州310027 上海科科阀门集团有限公司上海201802

流动性能是高温高压Y型截止阀组的关键性能指标,对截止阀组的运行具有重要意义。流速与流量的降低都会导致整体系统的工作效率下降。针对该问题,对全开工况下的DN15高温高压Y型截止阀组进行了研究。首先,以入口200 MPa、2000℃、出口常... 详细信息

流动性能是高温高压Y型截止阀组的关键性能指标,对截止阀组的运行具有重要意义。流速与流量的降低都会导致整体系统的工作效率下降。针对该问题,对全开工况下的DN15高温高压Y型截止阀组进行了研究。首先,以入口200 MPa、2000℃、出口常温真空为边界条件,对截止阀组内的流场进行了数值模拟,全面分析了截止阀组内部截止阀、球阀、喷管区域的流动特性,重点研究了阀组内流速的变化;然后,识别了流道中流动受限的区域,并提取了相应的特征结构参数,如喷管扩张段过渡角度数等;最后,采用非支配排序遗传算法,根据阀组的出口流速与出口流量这两项流动性能指标,对阀组内的流道局部结构参数进行了优化。研究结果表明:根据最优结构参数所得模拟结果与优化前的数据进行对比,出口流量提升了8.13%,出口速度提升了3.52%。该研究结论揭示了特定结构参数对截止阀组流动特性的影响机制,结合遗传算法与数值模拟方法,实现了特种阀门的流动性能升级目的,可对后续类似阀门的设计与性能优化工作提供一定的参考。

关键词：截止阀液压控制阀结构参数遗传算法流动性能阀组内流场分布非支配排序遗传算法

CARBIDES IN STEEL 4335 V

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Acta Metallurgica Sinica(English Letters) 1989年第4期2卷 262-268页

作者： ZHONG jiaxiang ZHENG Xiuhua xu Zongrui Beijing Institute of Technology,Beijing,ChinaBAI Dezhong Nei Monggol Machine Works No.2,Nei Monggol,China Beijing Institute of Technology,Beijing 100081,China

Three types of alloy carbides have been observed in tempered steel 4335V:M_3C,M_7C_3 and M_4C_*** precipitation temperatures are 200—700,400 and 500 ℃ *** com- position,morphologies and distribution patterns of the carbides as well as the relationship be- tween them and as-quenched substructures have been *** influence of the car- bides on the low temperature impact toughness of the steel has also been discussed.

关键词： steel 4335V carbide tempering

Studies on the efficiency of five repellents against Phlebotomus alexandri.

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中国寄生虫学与寄生虫病杂志 1988年第S1期 194-195页

作者： Jia jiaxiang, Guan Liren, xu Yongxiang, Wang Ge, Hao Kefeng: Institute of Parasitic Diseases, Chinese Academyof Preventive Medicine

The efficacy of five repellents were tested against Phlebotomus alexandri(a sandfly vector ofKala-azar)both in the laboratory and in the field in Meiyaogou,Turfan county,Xinjiang UygurAutonomous Region during 1986-1987.A total of 3301 females of *** were used in the la-boratory and 306 mantimes of volunteers were tested in the field。

关键词： Studies on the efficiency of five repellents against Phlebotomus alexandri

Characterization and Corrosion Resistance of Laser Clad-ding Al_2O_3-13%TiO_2 Coating on AZ91D Magnesium Alloy

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稀有金属材料与工程 2011年第S4期40卷 221-225页

作者： Qian Jiangang1,Zhang jiaxiang1,2,xu Min1,2,Li Shuqing2 1School of Chemistry and Environment,Beijing University of Aeronautics and Astronautics,Beijing 100191,China2National Key Laboratory for High Energy Density Beam Processing Technology,Beijing 100024,China Beijing Univ Aeronaut & Astronaut Sch Chem & Environm Beijing 100191 Peoples R China Natl Key Lab High Energy Dens Beam Proc Technol Beijing 100024 Peoples R China

An Al2O3-13%TiO2 (AT-13) ceramic coating was prepared on an AZ91D Mg alloy substrate by the laser plasma hybrid spraying technique.X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to identify the phases and to study the morphology,*** adhesion strength and the metallographic structure of the coating were measured by using a tensile testing machine and an optical microscope (OM),*** microhardness was measured using a micro Vickers hardness *** results show that after laser remelting,metallurgic bonding occurred at the interface between the Al transition layer and the *** adhesion strength of the coating increased from 17.01 to 28.47 *** coating became *** metastable γ-Al2O3 phase in the coating without laser remelting transformed completely into the stable α-Al2O3 *** microhardness was improved from HV0.05210 to HV0.05425 and the time of salt spraying increased from 288 to 336h.

关键词： laser plasma hybrid spraying Mg alloy corrosion resistance

量刑协商的应有之态——协商理论研究的发展与反思

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昆明学院学报 2021年第5期43卷 45-50页

作者：徐家祥青岛大学法学院山东青岛266101

随着认罪认罚从宽制度的全面展开,量刑协商制度的研究已逐步发展成为立体化研究体系。在大量研究基础的涵摄下,量刑协商产生了法官参与模式、辩审协商模式、家长模式、商谈审查模式等多种模式建构方法。结合与域外之比较,发现量刑协商... 详细信息

随着认罪认罚从宽制度的全面展开,量刑协商制度的研究已逐步发展成为立体化研究体系。在大量研究基础的涵摄下,量刑协商产生了法官参与模式、辩审协商模式、家长模式、商谈审查模式等多种模式建构方法。结合与域外之比较,发现量刑协商模式的建构需保持与司法适用的统一。在此基础上,以坚持协商契约性、坚持协商平等、构建统一协商平台的要义为指导,可以对与认罪认罚从宽制度更相契合的法官参与模式进行细化与修正。

关键词：协商程序辩诉交易法官参与权利保障程序公正

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红藤汤保留灌肠治疗慢性盆腔炎临床疗效观察

中国继续医学教育 2016年第13期8卷 205-206页

作者：徐加香江苏省宝应县妇幼保健院生育技术科江苏宝应225800

目的探讨红藤汤灌肠治疗慢性盆腔炎的临床疗效。方法回顾分析100例患者的临床资料,随机分为治疗组和对照组。治疗组50例,采用红藤汤灌肠治疗;对照组采用抗生素治疗。结果治疗组的总有效率达96%;对照组为78%,治疗组优于对照组,两组比较... 详细信息

目的探讨红藤汤灌肠治疗慢性盆腔炎的临床疗效。方法回顾分析100例患者的临床资料,随机分为治疗组和对照组。治疗组50例,采用红藤汤灌肠治疗;对照组采用抗生素治疗。结果治疗组的总有效率达96%;对照组为78%,治疗组优于对照组,两组比较有统计学意义(P<0.05)。结论经观察,红藤汤中药保留灌肠效果高于单一应用抗生素治疗患者的效果。此项临床观察效果适用于治疗慢性盆腔炎,能够改善患者症状,提高生活质量。

关键词：红藤汤灌肠慢性盆腔炎疗效观察