BPxN1-x薄膜的制备及磷元素对其光学能隙的影响

本文从应用出发，选择光学石英为衬底，采用热丝辅助射频化学气相沉积的方法沉积BPxN1—x薄膜，对样品进行了X射线衍射(XRD)、扫描电子显微镜(SEM)、紫外—可见等测试。XRD、SEM结果显示薄膜多晶态，表面形貌随时间变化，最终为胞状；紫外—可见光光谱结果显示BPxN1—x薄膜的紫外吸收边随沉积时间的加长、PH3流量的增加而向长波长方向移动。因此，该材料的光学能隙可以通过生长工艺适当调整。另外，BPxN1—x薄膜与液晶层能较好匹配等特性更使其适用于紫外空间光调制器。     

粉末材料中微夹杂缺陷的超声波检验

介绍了用超声波方法检测微夹杂缺陷的一些试验结果，比较了不同频率、不同试验方法检测能力的差异，并通过解剖试验对检出缺陷的性质、尺寸作了比较。     

用阻容保护装置抑制真空断路器的操作过电压

本文阐述了真空断路器用ＲＣ保护装置的原理。分析了用ＲＣ保护装置保护电力系统及其设备的试验结果。ＲＣ保护装置主要参数的选择。最后，讨论了有关ＲＣ保护装置的一些问题。     

压电复合材料PT－P（VDF／TeFE）的静水压压电性

用热轧辊机制备了压电复合材料ＰＴ－Ｐ（ＶＤＦ／ＴｅＦＥ），并利用ＬＣＲ电桥和Ｂｅｒｌｉｎｃｏｕｒｔ电路分别测量了其介电常数和压电常数，实验结果表明它具有良好的静水压压电特性。最后讨论了该复合材料在水听器中的应用     

Nutrient removal performance of an anaerobic–anoxic–aerobic process as a function of influent C/P ratio

The laboratory scale anaerobic–anoxic–aerobic (A²O) process fed with synthetic brewage wastewater was designed to investigate the effects of changing feed C/P ratio on the performance of biological nutrient removal (BNR) processes. In the experiment, the influent chemical oxygen demand (COD) concentration was kept at approximately 300 mg L^?1 while the total phosphorus concentration was varied to obtain the desired C/P ratio. Results showed that when the C/P ratio was lower than 32, phosphorus removal efficiency increased as C/P ratio increased linearly, while when the C/P ratio was higher than 32, the P removal efficiency was maintained at 90–98%, and effluent P concentration was lower than 0.5 mg L^?1. However, regardless of the C/P ratio, excellent COD removal (90% or higher) and good total nitrogen removal (75–84%) were maintained throughout the experiments. It was also found that very good linear correlation was obtained between COD uptake per unit P released in the anaerobic zone and C/P ratio. In addition, the P content in the wasted activated sludge increased with the decrease in the C/P ratio. Based on the results, it was recommended that the wastewater C/P ratio and its effects be incorporated into BNR design and operational procedures, appropriate C/P ratios were used to achieve the effluent treatment goals. Copyright © 2005 Society of Chemical Industry     

化学复合镀Ni-P-TiO_2光催化降解次甲基蓝

以钛酸丁酯为原料通过溶胶 凝胶法制备出粒径 30nm左右的纳米TiO2 ,利用化学复合镀在钢铁基底上形成Ni P 纳米TiO2 复合镀层 ,该复合镀层对次甲基蓝有较好的光催化降解作用 ,其催化性能与粉末状纳米TiO2 的催化性能大致相当。     

Kinetic Monte Carlo simulations of radiation induced segregation and precipitation

Kinetics of radiation induced segregation and precipitation in binary alloys are studied by Monte Carlo simulations. The simulations are based on a simple atomic model of diffusion under electron irradiation, which takes into account the creation of point defects, the recombination of close vacancy-interstitial pairs and the point defect annihilation at sinks. They can reproduce the coupling between point defect fluxes towards sinks and atomic fluxes, which controls the segregation tendency. In pure metals and ideal solid solutions, the Monte Carlo results are found to be in very good agreement with classical models based on rate equations. In alloys with an unmixing tendency, we show how the interaction between the point defect distribution, the solute segregation and the precipitation driving force can generate complex microstructural evolutions, which depend on the very details of atomic-scale diffusion properties.     

Formation of steady state size distribution of precipitates in alloys under cascade-producing irradiation

The effect of coherency loss on the development of precipitate size distribution under cascade-producing irradiation is considered. The nucleation of coherent precipitates, their growth followed by coherency loss and cascade-induced dissolution of large incoherent precipitates can occur simultaneously resulting in formation of a quasi-stationary size distribution of semicoherent precipitates. To describe this process we consider co-evolution of a mixed population of coherent, semicoherent and incoherent precipitates. Mathematically, the problem is formulated as a set of discrete rate equations of nucleation kinetics (the Master equation approach) which is also used for later stages of evolution. To solve the corresponding large set of equations (typically, more than 10⁵ equations) an efficient numerical method is developed. The simulation results obtained for material parameters and irradiation conditions typical for nuclear reactors show that the coherency loss affects considerably evolution of the precipitate population. Under certain irradiation conditions, both in solution-annealed alloys and in aged ones, the mean precipitate size and the number density during prolonged irradiation tend to steady state values, whereas the size distribution function of large precipitates narrows. The width of the quasi-stationary size distribution is controlled by cascade parameters. It was found that the asymptotic quasi-stationary state of the precipitate population may depend on initial state of the alloy.     

用于快速P/G网分析的Cholesky分解法图模型

通过对Cholesky分解法求解线性方程组的分析，建立Cholesky分解法三角化对称正定阵的图模型，并基于该模型及Mesh结构P／G网络的自身特点，提出一个P／G网快速分析算法．实验证明，该算法能大大降低Mesh结构P／G网络的分析运算时间和内存占用．     

基于P2P的协作系统研究

传统的协作存在固有的缺陷。系统可靠性和扩展性差，不能充分利用客户端资源。P2P系统不但架构灵活，有高可扩展性，而且能充分利用计算和网络资源。分析了协作系统采用P2P架构所具有的优点，并提出一个基于微软P2PSDK的协作系统设计与实现方案。