Experimental and Theoretical Study of Young Modulus in Micromachined Polysilicon Films

IntroductionThe development of microelectromechanicalsystems (MEMS) has achieved impressiveprogress with many new designs that couldpotentially lead to another industrial revolution.However,the long- term durability of the MEMSdevices,which requires a fun…     

Mechanical Deformation of Ship Stern-Shaft Mechanical Face Seals

In ship propeller shaft systems, the shaft seal is a mechanical face seal, which includes a stationary metal seal ring and a rotating ring. The seal faces are deformed with different loads. The deformation of the seal faces affects the performance of mechanical face seals, which leads to water leakage, so the seal face deformation must be analyzed. A mechanics model with deformation equations was developed to describe ship stern-shaft seals. An example was given to verify the deformation equations. The solution of the deformation equations gives a theoretical basis for the analysis of seal leakage and improvements of seal structures.     

几种硼配合物的合成及其光谱性质

本文叙述了几种硼配合物的合成和结果，介绍了这几种硼配合物的光谱，特别是紫外吸收光谱和荧光光谱．讨论和分析了这些配合物在不同溶剂中的光谱特征和性质．     

素馨醛（α—戊基肉桂醛）的合成

以庚醛和苯甲醛为原料在碱性介质中缩合合成α—戊基肉桂醛．讨论反应温度、反应时间和投碱量对产率的影响．     

芳香环的Diels - Alder 反应及其应用

本文综述８０年代中期以来芳香体系参与的Ｄｉｅｌｓ－Ａｌｄｅｒ反应及其在有机合成中的某些应用。     

软磁盘、硬盘的表面形貌和微摩擦特性

利用原子力／摩擦力显微镜,对市售的５种软磁盘及一种硬盘的表面形貌、１～１００ｎＮ载荷下的微摩擦性能及表面粘着性能进行了研究。结果表明：软磁盘主要由块状的磁粉颗粒组成;硬磁盘由环状磁道组成。硬盘的微摩擦力、表面粘着力、摩擦因子大于同样条件下的软磁盘,１２９ｍｍ（５．２５英）软磁盘的微摩擦力、表面粘着力、摩擦因子大于同一品牌的８６ｍｍ（３．５英）的软磁盘;探针与磁记录介质在大于２０ｎＮ载荷下的接触为塑性接触。     

SMA弹簧驱动器驱动机理及实验

为了将形状记忆合金(SMA)弹簧驱动器用于智能机械结构,需要了解各类SMA弹簧驱动器的驱动特性。该文在对SMA弹簧驱动器的电热驱动机理理论分析的基础上,进行了实验研究。实验结果表明:驱动器响应速度与驱动电流、预变形量、冷却速度、负载有关。偏动式驱动器回复速度和驱动电流成正比;差动式驱动器的响应速度受SMA弹簧冷却速度的制约,要控制驱动电流;差动驱动器比偏动驱动器性能优良,在智能机械结构中应用将有广阔的前景。     

Multigrid technique incorporated algorithm for CMP lubrication equations

Chemical mechanical polishing(CMP)is a manufacturing process used to achieve required high levels of global and local planarity,which involves a combination of chemical erosion and mechanical action.The study on mechanical removal action of CMP with hydrodynamic lubrication involved will help us to get some insights into the mechanism of CMP and to solve the lubrication problem of CMP.In this paper,a full approach scheme of multigrid technique incorporated with line relaxation is introduced for accelerating the convergence.The effects of various parameters on load and moments are simulated and the results of computation are reported.     

前交叉韧带移植物种类及拉力影响的有限元模拟

为了研究肌腱移植物种类及拉力对前交叉韧带重建长期效果的影响,在经过有效性验证的人体膝关节有限元模型(包含骨、半月板、软骨及主要韧带)基础上,对比了134N胫骨向前推力下两种移植物种类(双股及四股肌腱移植物)及3种重建后远期时的移植物实际拉力(0N,20N和40N)对关节稳定性及韧带受力的影响。结果表明:移植物实际拉力的增大会导致膝关节胫骨向后内侧移动并伴有外旋及外翻;移植物的受力也会变大,但应力分布并没有明显变化。由重建后远期时的膝关节稳定性及移植物受力结果可得,使用双股肌腱移植物且初始拉力为80N时,前交叉韧带重建的长期效果与完好关节最为接近。     

基于物元分析的城市综合体建筑火灾风险评价研究

为准确评价城市综合体建筑火灾风险等级,考虑到火灾风险影响因素的复杂性和不相容性,提出一种基于组合权和物元分析理论的城市综合体建筑火灾风险评价方法.首先,根据综合体建筑火灾特点与灾害机理,按人—机—料—法—环5要素确定评价指标体系,采用层次分析法(AHP)和熵权法计算指标组合权重;其次,针对评价的模糊性和不确定性,通过物元变换建立评价的物元体系,即确定火灾风险评价的经典域、节域和待评物元,通过计算等级贴近度确定综合体建筑火灾风险等级;最后,以武汉市某大型综合体为例,按照该方法确定该建筑火灾风险等级.结果表明,该综合体建筑火灾风险为安全,符合实际情况;与用于一般建筑火灾风险的其他评价方法相比,更为准确客观、简便易行.