Investigation of surface topography, morphology and structure of amorphous carbon films by AFM and TEM

Morphology and structure of amorphous carbon films deposited with a pulsed arc source (LASER-ARC) have been studied using microscopical methods (SEM, TEM and AFM), electron diffraction and spectroscopical investigation (EELS). The parameters of the arc source and the deposition conditions (substrate temperature) influence morphology and structure of deposited amorphous carbon films. Especially the incorporation and growth of particles, embedded in the film have been investigated. By particle analysis using an optical microscope a majority of particles that is smaller than 500 nm has been determined. The morphology has been also demonstrated similar by AFM and TEM images. Their number and size of particles is strongly influenced by the deposition temperature. The structure of amorphous film is characterized by the EELS-spectra, but the particle structure was not detectable.     

Spectroscopic investigation of Pt—methanol interface in perchloric acid medium by sum-frequency generation

We recorded vibrational spectra of the CO poison resulting from the electrochemical decomposition of CH₃OH on platinum by sum-frequency generation using the infrared free electron laser CLIO. At high CH₃OH concentration (0.1 M) in the electrolyte, both multi-bonded and linearly bonded CO are equally present. At lower CH₃OH concentration (0.004 M), the multi-bonded species is predominant. The CO poison still remains on the surface at potentials (0.05 V/NHE) close to the hydrogen evolution onset.     

D→Klv～l衰变过程的研究

用光锥QCD求和规则研究D→Klv～_l衰变过程，首先计算D→K跃迁形状因子，通过构造新的关联函数，消除了twist-3波函数的不确定性给计算结果所带来的影响，从而使计算结果更加精确. 计算得到的分支比与最近的实验数据相一致. 关键词： QCD光锥求和规则 D介子半轻衰变 分支比 形状因子     

醇体系中合成CuGaS2纳米晶及其形貌演变

以CuCl2·2H2O,自制的GaCl3和(NH2)2CS为原料,在乙二醇体系中合成了花状结构的CuGaS2纳米晶．产物分别用X射线粉末衍射仪、透射电子显微镜、场发射扫描电子显微镜、高分辩透射电子显微镜和X射线光电子能谱仪进行了表征．实验结果表明,220℃反应24 h得到均匀的花状纳米结构CuGaS2,它是由厚度80-100 nm的片晶组成．同时,通过反应时间的控制,可以清楚的看到由纳米颗粒到纳米球以及花状纳米结构的演变过程．另外,研究了反应温度、反应时间、溶剂等对产物和形貌的影响．此外,对花状结构纳米晶的生长机理进行了初步的探讨．室温荧光光谱表明,随粒径的降低,发光位发生了部分蓝移．     

适应市场经济规律,实行集中采购

本文从集中采购这一概念入手,提出了高校仪器、设备招标工作的基本程序及实行集中采购的一些具体做法,供大家参考.     

一种低电流纹波的低压大电流DC-DC变换器的研究

通过n个倍流整流结构交错并联方式用以进一步减小纹波电流。给出了电路的开关信号波形和仿真模型，并使用Pspice仿真软件对该模型进行仿真，取得满意效果。最后通过实验验证。这种结构特别适用于通信设备、计算机、宇航等领域的电源。     

改革开放以来我国思想解放划分标准研究

二十多年来我国改革开放和社会主义建设的历程,就是思想解放的历程。改革开放以来,我们党和国家先后 经历多次思想解放运动,由于选择的判断标准不同,得出的思想解放的具体次数是不一样的。根据已总结出来的七个 不同标准,可以得出“二次”、“三次”、“四次”和“五次”解放思想的结论。