A three-dimensional non-epitaxial atomistic growth model for thin-film deposition: effect of surface mobility

The effect of the atomic mobility on a film surface has been studied by using a three-dimensional atomistic thin-film deposition model which simulates three-dimensional thin-film images, surface profiles and cross-sectional area pictures. In addition, quantitative results of surface RMS roughness, average film thickness, atomic coordination number and its distribution, and solid fraction of the deposited thin films, were obtained from the simulations. When the film surface mobility increased from 0.3 to 3.0, RMS roughness decreased from 6.5 to 1.1, solid fraction increased from 0.27 to 0.56 and average film thickness decreased from 40 to 28, due to the reduction of the voids within the film. The full-width half magnitude of the atomic coordination distribution became narrower indicating the increased degree of crystallization. With increase in surface mobility crossing the boundary to 1.5, the film evolved from a porous or loose columnar structure with voids, to a densely packed fibrous grain structure which can be categorized by the zone structure models.     

自韧Si3N4陶瓷的显微结构及其性能研究

利用热压的方法制得室温断裂韧性和抗弯强度分别为１１．２ＭＰａ·ｍ￣（１／２）、８２３ＭＰａ，高温（１３５０℃）断裂韧性和抗弯强度分别为２３．９ＭＰａ·ｍ￣（１／２）、６３０ＭＰａ的自韧Ｓｉ＿３Ｎ＿４陶瓷。研究了显微结构和力学性能之间的关系。结果表明：玻璃相的含量、β－Ｓｉ＿３Ｎ＿４的长径比等对性能有重要影响。分析了自韧Ｓｉ＿３Ｎ＿４陶瓷的增韧机理，通过ＳＥＭ明显观察到Ｓｉ＿３Ｎ＿４中存在裂纹偏转、分支和β－Ｓｉ＿３Ｎ＿４拔出现象。     

高温过热器12Cr2MoWVTib（102）钢管的显微组织和相结构分析

本文对原始状态和在火力发电厂使用不同时间的高这热器１０２钢管进行了显微组织和相结构变化规律的探讨和研究。显微组织研究表明，１０２钢管在高温高压下长期运行过程中，使用温度对显微组织和碳化物相有明显影响，而使用时间对其影响不如温度影响强烈。碳化物颗粒图象分析表明，碳化物随着使用时间缓慢长大，而新的碳化物不沉淀，使颗粒总数不断增加，颗粒，间距逐渐缩小。Ｘ射线衍射数据证明，钢管在高温长期使用过程中，ＭＣ相     

沉积方式与基体材料对TiN薄膜内应力的影响

本文研究了TiN薄膜在化学气相沉积、物理气相沉积(包括热灯丝离子镀和多弧离子镀)以及等离子增强化学气相沉积等不同生成条件下的内应力变化。并通过改变钢及硬质合金基体的化学成份和表面状态。考察了基体材料对薄膜应力的影响。在此基础上,对薄膜内应力的形成机制进行了分析讨论。     

变速箱结构设计专家系统技术的研究

结构设计是机械产品设计过程中的重要环节，解决结构设计的智能化不但可以缩短产品的设计周期，而且还可以降低成本，提高设计质量。专家系统是解决智能化设计的技术之一。本文讨论有关结构专家系统的几个关键技术，主要包括系统的控制策略，面积对象的知识表达方式及结构设计的并行设计     

Microwave spectra of CD3OH methanol

The microwave spectrum of CD₃OH has been studied over the 8 to 58 GHz region, and numerousb-type transitions have been assigned. Many of these belong toP subbranches which descend to the microwave region from subband origins lying much higher in the far-infrared, pass through zero frequency, and return upward again. Others are members ofb-typeQ branches which extend across the region. As well, variousa-typeK-doublet lines arising as transitions directly across the split levels of asymmetry doublets have been identified.     

紫草色素的研究

紫草色素原植物系紫草科Broaginaceae几种植物的根，又称紫根色素。该研究首次用人工栽培的硬紫草(Lithospermum erythrohizon Sieb.)的根，作了加工工艺和特性的研究。产品得率近1％，色价E 1^1Q5nm达150以，卫生指标符合有关规定，是种理想的脂溶性红色素。     

A millimeter-wave omnidirectional dielectric rod metallic gratingantenna

A new millimeter-wave omnidirectional dielectric rod metallic grating antenna is investigated theoretically and experimentally, in this paper. The radiation characteristics of the antenna are carefully investigated by a rigorous formulation for the TE₀₁-mode and TM₀₁-mode excitation in the Ka-band frequency range. Based on the analysis, an omnidirectional antenna excited by the TE₀₁ mode is designed and measured. The measured results are compared with theoretical predictions and good agreement is found. Extensive numerical results are given to establish some useful guidelines for the design of the omnidirectional antenna     

1477 nm LD泵浦掺铒光纤放大器的研究

报道了采用１４７７ｎｍ激光二极管（ＬＤ）泵浦的掺铒光纤放大器的实验结果。研究了放大器的增益和时域特性。对１５２０ｎｍ的信号光，获得了２３ｄＢ的增益，泵浦效率为２．２８ｄＢ／ｍＷ。低频脉冲信号经过放大器后未发生波形畸变。