Amorphous chromium silicide formation in hydrogenated amorphous silicon

The interaction between thin films of hydrogenated amorphous silicon and sputter-deposited chromium has been studied. Following deposition of the chromium films at room temperature, the films were annealed over a range of times and temperatures below 350°C. It was found that an amorphous silicide was formed only a few nanometers thick with the square of thickness proportional to the annealing time. The activation energy for the process was 0.55±0.05 eV. The formation process of the silicide was very reproducible with the value of density derived from the thickness and Cr surface density being close to the value for crystalline CrSi₂ for all films formed at temperatures ≤300°C. The specific resistivity of the amorphous CrSi₂ was ≈600 μΩ·cm and independent of annealing temperature.     

化学束外延

本文介绍了化学束外延(CBE)的发明和发展,论述了CBE的原理和设备。文中还介绍了最近提出的一种生长机理。     

过共晶Al－Si合金共生区激光表面处理

用２ｋＷ连续ＣＯ２激光对过共晶Ａｌ－１８Ｓｉ合金以不同能量密度和扫描速度进行快速熔凝处理。用扫描电镜、电子微区分析仪分析了微观结构。从计算机对Ａｌ－Ｓｉ合金ｆ－ｎｆ系统的非平衡理论计算所得的共生区及实验结果的分析可见，当能量密度和扫描速度决定的凝固条件处于共生区中部时，过共晶Ａｌ－Ｓｉ合金激光表面处理可以得到共晶间距低于２００ｎｍ的完全共晶结构。     

In－BiCaVIG的晶体生长与性能

本文报导了用助熔剂法成功地生长大尺寸掺铟ＢｉＣａＶＩＧ晶体的方法以及实验结果，介绍了该单晶在近红外区的磁光器件中的重要应用。     

纤维共晶生长界面前沿三维扩散场解析

修正Ｊａｃｋｓｏｎ和Ｈｕｎｔ关于在垂直生长方向截面上溶质扩散各向同性假设，求解三维Ｌａｐｏｌａｃｅ方程，获得纤维共晶生长界面前沿三维稳态扩散场，并证明Ｊａｃｋｓｏｎ和Ｈｕｎｔ的二维模型是实际生长的二维简化和一阶近似，并用丁二腈（ＳＣＮ）一梓脑（ＣＡＭ）纤维共晶系统计算生长界面前沿溶质分布。     

大尺寸氟化铅晶体的生长

描述了不用高真空条件，在通常的Ｂｒｉｄｇｍａｎ－Ｓｔｏｃｋｂａｒｇｅｒ炉中，用高温下的反应方法，消除了原料及生长炉内残存的Ｏ＾２－及ＯＨ＾－，生长出优质，大尺寸的β－ＰｂＦ２晶体。在晶体生长时，出现的主要问题是在晶体中的针状结构及开裂，但可通过控制条件来解决。     

Studies of photoconductivity in β-Apo-8′ carotenal

The photoconductive properties of a carotenoid polyene,β-Apo-8′ carotenal in polycrystalline form has been studied. The growth of the photocurrent shows an overshoot in the growth-time curve before steady state value is attained. This behaviour of photocurrent is proposed to be due to higher value of recombination coefficient than trapping coefficient. From the temperature dependence study it is observed that the steady state photocurrent, at first increases with increase of temperature, attains a maximum at a particular temperatureT _max and then decreases with temperature. TheT _max value agrees with the temperature above and below which steady state photocurrent is attained differently. Monomolecular and bimolecular recombination processes at two temperature regimes are proposed to account for the observed behaviour. The dependence of photocurrent with excitation light intensity and wavelength study provide information on the carrier generation processes. The fast decay of photocurrent have been observed at different temperatures and from this study the decay constant is calculated and it is found to be temperature independent.     

A computational model for analysing interactive buckling and delamination growth in composite structures

In this paper, a unified method is presented: (i) to model delaminated stiffened laminated composite shells; (ii) for synthesising accurate multiple post-buckling solution paths under compressive loading; and (iii) for predicting delamination growth. A multi-domain modelling technique is used for modelling the delaminated stiffened shell structures. Error-free geometrically nonlinear element formulations — a 2-noded curved stiffener element (BEAM2) and a 3-noded shell element (SHELL3) — are used for the finite element analysis. An accurate and simple automated solution strategy based on Newton type iterations is used for predicting the general geometrically nonlinear and postbuckling behaviour of structures. A simple method derived from the 3-dimensionalJ-integral is used for computing the pointwise energy release rate at the delamination front in the plate/shell models. Finally, the influence of post-buckling structural behaviour and the delamination growth on each other has been demonstrated.     

鱼类耳石扫描电镜样品制备与观察

本文介绍了一种鱼类耳石样品的扫描电镜制样方法，通过对草鱼耳石进行包埋，抛磨，并用合适的腐蚀剂处理，用ＳＥＭ成功地观察了耳石的日轮及超微结构，该方法简便易行，保证所观察耳石样品的微观结构完整与清晰。     

Morphological and kinetics study of PEO/PVC blends

The kinetics of spherulite radial growth and the morphology of the compatible system PEO/PVC have been studied by optical microscopy. The usual spherulite radial growth behaviour has been found for compatible blends with PEO content higher than 70%. For lower composition, distortion of the usual spherulite morphology has been observed; the anomalies have been attributed to partial miscibility of the components.