吸湿凉爽机织物的结构设计与性能

为研究织物组织结构与复合纱线线密度对织物凉爽性能的影响,将线密度为7.4和9.8 tex涤纶分别与线密度为7.8 tex锦纶反向加捻、并线后作为纬纱,以8.3 tex涤纶/竹浆纤维50/50混纺纱作经纱,设计平纹、二上一下斜纹和透孔组织织物.测试织物的瞬间接触凉感、热湿舒适性能及织物干、湿态升温曲线,并采用凉爽温度指数对织物的综合凉爽性能进行评价.研究结果表明:6种设计织物的瞬间接触凉感均高于标准,且平纹织物最好,纬纱粗细对瞬间接触凉感影响不显著;透孔织物透气性最好,且在人体出汗的状态下具有较好的导湿散热性能.平纹织物凉爽温度指数最高,最大凉爽温度为2.8℃,综合凉爽性能最好.     

锡磷青铜带材表面黑丝黑点的分析及预防措施

本文通过全面系统的实验分析，确认锡磷青铜带材表面黑丝黑点源于生产过程中硫对铜带表面的污染和腐蚀。提出了预防黑丝黑点的一系列有效措施。采取这些措施后，成材率提高了3％，显著地降低了生产成本，增强了产品的竞争能力。     

基于进化算法的常减压装置模拟

提出了基于优选优生进化算法（Select—best and prepotency evolution algorithm，SPEA）的常减压装置模拟方法。以各塔的温度分布为目标，基于生产过程和分析数据，采用SPEA确定各塔板Murphree效率，从而精确描述各塔板平衡偏离程度。在实际应用中，获得具有良好精度的常减压装置模型。系统分析了SPEA算法的关键参数——优选领域大小与计算复杂性及寻优性能之间的关系，结果显示其取值为群体规模的10％最为合适。     

The First Template‐Free Growth of Crystalline Silicon Microtubes

A simple template‐free high‐temperature evaporation method was developed for the growth of crystalline Si microtubes for the first time. As‐grown Si microtubes were characterized using X‐ray diffraction, scanning electron microscopy, transmission electron microscopy, and room‐temperature photoluminescence. The lengths of the Si tubes can reach several hundreds of micrometers; some of them have lengths on the order of millimeters. Each tube has a uniform outer diameter along its entire length, and the typical outer diameter is ≈ 2–3 μm. Most of the tubes have a wall thickness of ≈ 400–500 nm, though a considerable number of them exhibit a very thin wall thickness of ≈ 50 nm. Room‐temperature photoluminescence measurement shows the as‐synthesized Si microtubes have two strong emission peaks centered at ≈ 589 nm and ≈ 617 nm and a weak emission peak centered at ≈ 455 nm. A possible mechanism for the formation of these Si tubes is proposed. We believe that the present discovery of the crystalline Si microtubes will promote further experimental studies on their physical properties and smart applications.     

一种支持QoS的拓扑自适应动态组播路由算法

YAM、QoSMIC、DSDMR等一类支持QoS的动态组播路由算法允许组播成员动态地加入和离开，同时为接收方提供多个可选择的组播接入路径，以满足不同应用的QoS需求。但这些算法普遍存在控制信令开销大和结点加入时延长，可扩展性不好等问题。本文在分析这些算法的基础上，提出改进的支持QoS的动态组播路由算法，即拓扑自适应动态组播路由（Topology Adaptive Dynamic Multicast Routing，TADMR）算法。该算法避免了以往算法中大部分盲目的路径搜索，并使结点加入时延不再受限于固定的等待时钟，而与网络拓扑相自适应。性能分析和仿真结果表明，该算法具有较低的控制信令开销和结点加入时延，适用于各种网络规模和群组规模，具有良好的可扩展性。     

合成吡啶类化合物用催化剂的再生行为研究

对合成吡啶类化合物用的失活催化剂上的结焦物进行了元素分析 ,并着重对失活催化剂的再生行为进行了研究。得到了不同失活程度催化剂的再生曲线及相同失活程度、不同再生条件下的再生曲线。经回归求得了一简单的再生反应动力学经验方程式 ,其中反应级数为碳含量的 1.16 5级 ,活化能为 4 2 .5 72kJ/mol,计算值与实验值的平均相对误差为 6 .5 %。     

ZnGa2O4纳米晶的制备和结构表征

采用喷射共沉淀法制备了ZnGa2O4 纳米晶，XRD、SEM和TEM结构分析结果表明，喷射共沉淀法制备的ZnGa2O4的纳米晶颗粒细小均匀，形状完整，与化学共沉淀法相比，粒子尺寸明显减小，小于10nm，同时ZnO杂相峰消失，分析了喷射共沉淀法的机理，并对实验结果进行了解释。     

A new efficient method for one‐pot conversions of aryl carboxylic acids into nitriles without solvent

A new efficient method for synthesising nitriles, important organic reagents, is reported in this paper. In an environmentally benign solvent‐free system, aryl carboxylic acids were converted into the corresponding nitriles via one‐pot reactions, by amidation with ethyl carbamate followed by dehydration with thionyl chloride, in excellent yields. The results showed that the method has the advantages of lower cost, higher yield, less pollution and greater ease of work‐up. Copyright © 2008 Society of Chemical Industry     

Modeling wireless fading channels via stochastic differential equations: identification and estimation based on noisy measurements

This paper is concerned with modeling and identification of wireless channels using noisy measurements. The models employed are governed by stochastic differential equations (SDEs) in state space form, while the identification method is based on the expectation-maximization (EM) algorithm and Kalman filtering. The algorithm is tested against real channel measurements. The results presented include state space models for the channels, estimates of inphase and quadrature components, and estimates of the corresponding Doppler power spectral densities (DPSDs), from sample noisy measurements. Based on the available measurements, it is concluded that state space models of order two are sufficient for wireless flat fading channel characterization.     

镍氢电池负极用低成本储氢合金的研究

研究了ABS型储氢合金在低Co含量条件下，随B组元替代元素Co，Al，Si等含量的变化对合金电化学性能的影响规律，同时研究了A组元中不同La／Ce比对合金电化学性能的影响情况。结果表明，随合金中Co含量的降低，合金的活化性能和放电容量得以改善，但合金的循环寿命下降也比较明显；在试验范围内，随Al元素的加入，合金的循环寿命得以改善，但材料的放电容量和活化性能均有所下降；随合金La／Ce比的降低，合金的放电容量略有下降，但其循环寿命和放电电压平台有较大提高。