Mechanical Properties of Single-Layer Diamond Reinforced Poly(vinyl alcohol) Nanocomposites through Atomistic Simulation

Low-dimensional carbon nanostructures are ideal nanofillers to reinforce the mechanical performance of polymer nanocomposites due to their excellent mechanical properties. Through molecular dynamics simulations, the mechanical performance of poly(vinyl alchohol) (PVA) nanocomposites reinforced with a single-layer diamond – diamane is investigated. It is found the PVA/diamane exhibits similar interfacial strengths and pull-out characteristics with the PVA/bilayer-graphene counterpart. Specifically, when the nanofiller is fully embedded in the nanocomposite, it is unable to deform simultaneously with the PVA matrix due to the weak interfacial load transfer efficiency, thus the enhancement effect is not significant. In comparison, diamane can effectively promote the tensile properties of the nanocomposite when it has a laminated structure as it deforms simultaneously with the matrix. With this configuration, the interlayer sp³ bonds endows diamane with a much higher resistance under compression and shear tests, thus the nanocomposite can reach very high compressive and shear stress. Overall, enhancement on the mechanical interlocking at the interface as triggered by surface functionalization is only effective for the fully embedded nanofiller. This work provides a fundamental understanding of the mechanical properties of PVA nanocomposites reinforced by diamane, which can shed lights on the design and preparation of next generation high-performance nanocomposites.     

Experimental study of crystal anisotropy based on ultra-precision cylindrical turning of single-crystal calcium fluoride

To realize ultimately efficient signal processing, it is necessary to replace electrical signal processing circuits with optical ones. The optical micro-resonator, which localizes light at a certain spot, is an essential component in optical signal processing. Single-crystal calcium fluoride (CaF₂) is the most suitable material for a highly efficient optical micro-resonator. The CaF₂ resonator can only be manufactured by ultra-precision machining processes, because its crystal anisotropy does not allow the application of chemical etching. However, the optical micro-resonator's performance depends definitely on the surface integrity.This study investigated the relationship between surface quality after ultra-precision machining and crystal anisotropy. Firstly, crack initiation was investigated on the (1 0 0), (1 1 0), and (1 1 1) planes using the micro-Vickers hardness test. Secondly, brittle-ductile transition was investigated by orthogonal cutting tests. Finally, cutting performance of cylindrical turning was evaluated, which could be a suitable method for manufacturing the CaF₂ resonator. The most difficult point in cylindrical turning of CaF₂ is that the crystalline plane and cutting direction vary continuously. In order to manufacture the CaF₂ optical micro-resonator more efficiently, analysis was conducted on crack initiation and surface quality of all crystallographic orientations from the perspective of slip system and cleavage.     

基于AFM的微结构加工实验研究

本文建立了微动工作台和原子力显微镜相结合的微加工系统，在该系统上采用金刚石针尖进行微加工实验，与SPI系统本身的刻划软件刻划出的图形进行了比较分析，得出这个系统适合微结构的加工；并给出了采用该方法加工的1111面及多边形面微结构；还分析了金刚石针尖几何角度及SPM和工作台的相关参数对加工的影响。     

一个计算机动画转头模型

本文提出一个用于计算机动画的转头模型。它利用头部的正面和侧面形象来构造出头的三维结构形象，然后按指定的旋转轴旋转该结构，经过边缘轮廓提取及隐线消除，最终得到正确的转头过程序列画面。     

预处理工艺对硬质合金与金刚石膜间粘结力的影响

在两种经不同预处理的硬质合金YG8基底上，采用微波等离子体化学气相沉积法，在微波功率2kW，压强4.0kPa和6.5kPa，CH4和H2流量分别为1.6cm/s和100.0cm/s的条件下生长金刚石薄膜。利用X射线衍射检测了金刚石薄膜是否存在，用拉曼光谱分析了薄膜的质量，用金相显微镜观察了薄膜的洛氏硬度压痕，标定并比较了不同预处理工艺膜与基底的结合力。实验结果表明，不同的预处理方法对于粘结力的影响不大，最主要的因素是钴含量的多少。     

面向21世纪课程教材对地方综合大学电工学教学改革的影响--广西大学使用面向21世纪电工学课程系列教材的实践与探索

阐述了我校使用“面向21世纪”电工学课程系列教材的实践与探索过程，以及对我校电工学教学所产生的转折性影响和积极的导向作用，最后对教材提出了几点建议。     

以入世为契机,进一步推进电力科研院所企业化转制

我国入世和融入经济全球化，将给中国经济运行的大环境带来深刻变化，科技事业也面临着全新挑战。电力科研所实行企业化转制，与国际接轨，按照国际规则办事势在必行。作者作为电力科研单位的一把手就电力科研院所的企业化转制阐述了个人的观点。转制必须有利于回忆科技创新和高新技术产品的开发；必须有利于抓紧培养和造就复合型人才队伍；必须有利于更好地为电网、为发供电企业提供规范化、制度化、长期化和现代化的全方位服务。     

金刚石膜的计算机虚拟制备技术中的分子动力学模拟

综述了近年来金刚石薄膜形成过程的分子动力学（Molecular Dynamics，简称MD）模拟研究，详细地阐述了原子间相互作用势的选取，总结了不同沉积条件下MD的计算模型和几种典型情况下的模拟结果。研究表明：在原子尺度上，MD方法能较全面地提供有关膜生长的信息，对进一步了解金刚石膜形成的微观机制以及为细观层次仿真提供基本信息均具有重要意义。     

金刚石薄膜异质外延的研究进展

主要介绍金刚石薄膜在Si上异质外延的研究状况。综述了外延金刚石薄膜的偏压形核 ,SiC过渡层的影响及一些实验参数对外延薄膜质量的影响等 ,并论述了发展方向