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介绍了一种微型电机轴的绿色加工方法,它突破了微型电机轴传统的加工方法,改车削两端半球面为冷镦,变外圆磨削为冷拉.由于是无切屑加工,节省了材料;由于取消了热处理,节省了能源;由于省去了磨削工序,节约了成本,减轻了对环境的污染,因而实现了微型电机轴的绿色加工. 相似文献
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阐述了国内外汽车制造企业售后服务信息化发展现状,分析了汽车售后服务业务流程,研究了ASP模式的协同应用平台,并根据汽车售后服务的业务特点构建了基于协同应用平台的售后服务系统体系结构。最后,设计了系统的模块,描述了其基本功能,并对系统进行了开发。 相似文献
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运载火箭贮箱壁板机铣装夹技术研究 总被引:1,自引:0,他引:1
为进一步提供运载能力,对新一代运载火箭提出了减重要求,其贮箱壁板加工工艺方法由机械铣切替代化学铣切。围绕某型号运载火箭的研制需求开展了贮箱壁板机铣装夹技术研究。通过对壁板的结构特点及加工工艺性分析,确定了"先弯后铣"的工艺方法。通过开展工艺试验,定位了引起产品超差的主要因素,分析了超差原因,制定了解决措施,引出了真空吸附装夹技术研究的需求,阐述了真空吸附装置的设计方案。结合真空吸附原理,进行了机铣过程切削力理论计算,确定了真空吸附系统的吸附力、吸附面积,优化了密封结构设计,实现了柔性装夹。最终通过合格产品的试制,验证了真空吸附装夹装置的有效性。 相似文献
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研制了一种新型直线超声电机,首先对其驱动机理进行了探讨,对定子表面质点椭圆运动的形成进行了分析,结合电机输入电压信号的时序阐明了电机工作模态的激发过程;其次对电机结构进行了设计,确定了振子尺寸,组装了一台直线超声电机. 相似文献
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王振道 《机械工人(热加工)》2008,(18):80-81
阐述了液压油箱的结构和制造工艺。通过改进结构,方便了焊接操作;通过细化工艺,确定了焊接规范,从而控制了飞溅,减少了油箱内的清理量,提高了清洁度。 相似文献
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针对港口上常用的长撑杆散货抓斗,分析影响抓取性能的参数,根据抓斗结构建立了无量纲空间尺寸模型,进行了静力学分析,提出以最小抓取力矩为静力学计价指标,并绘制了性能图谱。根据性能图谱建立了多变量非线性优化模型,应用matlab遗传算法工具箱进行了求解,对抓斗的几何参数进行了优化设计,修正了传统依靠经验设计的抓斗参数,提高了抓斗的抓取力矩,从而提高了抓斗的抓取性能和效率,结合实例对模型的有效性进行了验证分析。 相似文献
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Palyno‐morphological characteristics of gymnosperm flora of pakistan and its taxonomic implications with LM and SEM methods
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Raees Khan Sheikh Zain Ul Abidin Mushtaq Ahmad Muhammad Zafar Jie Liu Hafiza Amina 《Microscopy research and technique》2018,81(1):74-87
The present study is intended to assess gymnosperms pollen flora of Pakistan using Light Microscope (LM) and Scanning Electron Microscopy (SEM) for its taxonomic significance in identification of gymnosperms. Pollens of 35 gymnosperm species (12 genera and five families) were collected from its various distributional sites of gymnosperms in Pakistan. LM and SEM were used to investigate different palyno‐morphological characteristics. Five pollen types (i.e., Inaperturate, Monolete, Monoporate, Vesiculate‐bisaccate and Polyplicate) were observed. Six In equatorial view seven types of pollens were observed, in which ten species were sub‐angular, nine species were Traingular, six species were Perprolate, three species were Rhomboidal, three species were semi‐angular, two species were rectangular and two species were prolate. While five types of pollen were observed in polar view, in which ten species were Spheroidal, nine species were Angular, eight were Interlobate, six species were Circular, two species were Elliptic. Eighteen species has rugulate and 17 species has faveolate ornamentation. Eighteen species has verrucate and 17 have gemmate type sculpturing. The data was analysed through cluster analysis. The study showed that these palyno‐morphological features have significance value in classification and identification of gymnosperms. Based on these different palyno‐morphological features, a taxonomic key was proposed for the accurate and fast identifications of gymnosperms from Pakistan. 相似文献
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用热压成型法分别制备了纳米、微米石墨填充聚四氟乙烯(PTFE)的复合材料,对纯PTFE和复合材料进行了硬度、耐磨性和拉伸试验,用SEM观察了拉伸断口形貌.结果表明:纳米和微米石墨均能提高复合材料的硬度和耐磨性,而复合材料的抗拉强度和断后伸长率均有所下降;纳米石墨/PTFE复合材科的硬度、耐磨性、抗拉强度和断后伸长率均比微米石墨/PTFE复合材料的高;当纳米石墨质量分数为7%时,复合材料的综合性能较好,当质量分数大于7%后,复合材料的断后伸长率迅速下降;纳米石墨与PTFE相容性较好,在PTFE中的分布均匀. 相似文献
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柔性工作流技术研究的现状与趋势 总被引:26,自引:2,他引:26
工作流变更和异常是柔性研究的重要内容,界定了这两个概念,并从不同的角度,分别对系统的灵活性、动态性和自适应性等进行了研究.从理论和实现两个层次上深入探讨了柔性工作流的解决策略和方法,介绍了支持柔性的系统体系结构和元模型,并对一些具体的实现机制进行了讨论和比较,介绍了一些成熟的工作流系统,分析了系统中相关的柔性实现;最后,说明了理论研究和系统实践的未来趋势和发展方向. 相似文献
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材料多轴疲劳破坏准则回顾 总被引:6,自引:1,他引:6
对多轴疲劳载荷作用下材料的疲劳破坏准则作了系统的回顾,按照用于描述材料疲劳破坏的参量,将多轴疲劳破坏准则划分为三类,应力准则、应变准则、能量准则。分别对这三种准则按多轴比例加载及多轴非比例加载两种情况进行阐述,并进行简单的评述。 相似文献
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HPLC-ICP-MS hyphenated techniques were developed for the elemental speciation analysis. Different species of I, Br and Hg were successfully separated and determined. The linier dynamic ranges, the detection limits were discussed. The compound independent calibration (CIC) phenomenon for HPLC-ICP-MS techniques were found and its good potential in applications were discussed as example. 相似文献
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J. N. Turner J. W. Swann D. H. Szarowski K. L. Smith M. Marko A. Leith 《Microscopy research and technique》1991,18(1):11-23
Three-dimensional morphology and electrophysiology were correlated from individual neurons in a thick brain slice preparation. The hippocampal formation from immature and adult rats was cut transverse to the longitudinal axis into 500 μ Um-thick slices which were maintained under physiologic conditions. Individual neurons were impaled and physiologically characterized using microelectrodes. Recordings were made from the soma and in some cases from a dendrite. The impaled neurons were filled through the microelectrode with the fluorescent dye lucifer yellow and imaged by confocal scanning laser microscopy using an analog preprocessor. As many as 180 optical sections were recorded as a function of depth through the slices. Images are presented as a series of optical sections, stereo pairs, or three-dimensional reconstructions. Both stereo contouring and volume rendering methods were employed, and the reconstructions were viewed from any arbitrary perspective. Dendritic and axonal fields were separated from each other and displayed separately or as different pseudocolors. The three-dimensional reconstructions provided perspectives that were difficult or impossible to appreciate by viewing the optical sections or conventionally formed stereo pairs. 相似文献