PROTEL在表面贴装CAD设计中自动布线探讨

以CAD设计软件PROTELFORWINDOWS在表面贴装中自动布线应用为例 ,探讨了如何设置布线、布局参数 ,如何更好运用EDA工具的问题     

神华煤炭机械化采样最大允许偏倚值的确定

针对煤炭采样中最大允许偏倚(B)值的研究现状及其问题进行了分析,并结合实验探讨了神华煤炭机械化采样最大允许偏倚的参考值,指出测定10%最大(最小)粒度被排斥时的偏倚能够用于确定机械化采样最大允许偏倚值的大小。     

Review on oxides of antimony nanoparticles: synthesis,properties, and applications

In this article, synthesis methods, properties, and applications of antimony oxide nanoparticles are reviewed. Oxides of antimony exist in three phases, namely antimony trioxide, antimony tetroxide, and antimony pentoxide. Physical and optical properties of these nanoparticles are reviewed and compared with their bulk forms. According to literature works, a total of eight synthesis methods have been used to produce these nanoparticles. The size, distribution, shape, and structure of the nanoparticles which are synthesized by different methods are compiled and compared. It is reported that the properties are strongly dependent on the synthesis methods. Advantages and disadvantages of each synthesis method are discussed and compared. Most literatures report on the optical and physical properties of the nanoparticles. Reports on the electrical properties are scarce. As the applications of these nanoparticles cover a wide range, several challenges must be overcome to use them well. These challenges are also being presented and explained in this article.     

Effects of Out-of-Plane Disorder in CaFe<Subscript>1−<Emphasis Type="Italic">x</Emphasis></Subscript>Co<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript>AsF System

We perform oxygen doping experiments in the CaFeAsF and CaFe_0.88Co_0.12AsF compounds. In the parent compound CaFeAsF, partial replacement of F by O leads to an increase of resistivity and a weakening of spin-density wave transition, indicating that the out-of-plane disorder strongly affects the electronic and magnetic properties of the system. In the CaFe_0.88Co_0.12AsF_1−x O _x system, the doping of oxygen leads to the suppression of superconductivity, reflecting the importance of Ca–F layer disorder in this system.     

Suppression of thermal denaturation of myosin and salt-induced denaturation of actin by sodium citrate in carp (Cyprinus carpio)

The effect of sodium citrate (Na-citrate) on myosin and actin denaturation in myofibrils was investigated. Na-citrate significantly suppressed the thermal inactivation of Ca²⁺-ATPase of carp myosin in a concentration-dependent manner. The effect was greater than that of sorbitol. A similar effect was observed with myofibrils in which myosin is stabilized by F-actin binding. Na-citrate dissolved myofibrils at lower concentration than NaCl. Nevertheless, Na-citrate at 1 M failed to denature F-actin in myofibrils, while 1 M NaCl denatured F-actin almost completely. Na-citrate suppressed the NaCl-induced F-actin denaturation. Sorbitol did not show such protective effect on F-actin denaturation. Moreover, Na-citrate suppressed the freeze denaturation of myofibrils at lower concentration than sorbitol. Thus, Na-citrate was proved to be superior to sorbitol. It was suggested that Na-citrate alone could substitute sorbitol as cryoprotectant in surimi and NaCl as dissolving reagent of myofibril in thermal gel production.     

MATLAB在计算机辅助数值分析与计算中的应用

简要介绍了MATLAB语言，并把MATLAB语言应用于计算机辅助数值分析与计算中，在MATLAB软件环境下研制了计算机辅助数值分析与计算（CANAC）软件包，最后用一个典型实例较为深入地对其使用方法，特点和效果进行讨论，实践表明，该软件包使用效果良好。     

基于拼音模型的声学层识别的研究

本文介绍拼音模型的原理及应用。拼音模型是累加语言模型中同音字的相关数据后得到的3元模型,是在原来的声学模型和语言模型之间增加的一个新环节,可用来求取相关拼音串的先验概率,实验结果表明,用它作为声学层识别的后处理,可使第1名的识别率提高13个百分点,可使前5名的识别率与原来声学模型输出前10 的识别率相当。     

圆机电子提花系统的总体设计

通过对国内外圆机提花机构的分析和比较，提出一种圆机电子提花系统的设计方案，并针对国产提花机的现状，为机械提花机构的改造和电子提花系统的研制提供了一条新的思路     

Lignin-degrading enzyme production by Bjerkandera adusta immobilized on polyurethane foam

Production of the lignin-degrading enzymes lignin peroxidase (Lip), manganese peroxidase (MnP), and laccase (Lac) by the white-rot fungus Bjerkandera adusta was investigated experimentally using polyurethane foam (PUF) as a carrier of immobilized fungal mycelia. An immobilized cell culture with a low-nitrogen medium yielded significantly greater LiP, MnP, and Lac activities in comparison with those obtained in a liquid culture. The maximum activities of the three enzymes were 450, 370, and 100 U/ml, respectively, under the following incubation condition: glucose concentration, 20 g/l; temperature, 30 degrees C; pH 4.5. The activities of MnP and Lac were significantly higher than those reported using other incubation methods. Lignin was degraded to the extent of 40% and its decolorization ratio was about 70% at an incubation time of 40 h using lignin-degrading enzymes from B. adusta. Six different isozymes of MnP were synthesized by B. adusta, two of which exhibited high MnP activity. Our preliminary finding that extracellular enzymes from B. adusta are capable of degrading and decoloring lignin makes these enzymes attractive for further research aimed at their large-scale application in lignin depolymerization, pulp biobleaching, and the degradation of toxic pollutants.     

低压真空断路器的发展前景

通过与高压真空路器和ＭＥ系列低压断路器对比，论述了低压真空断路器的经济和技术性能以及发展前景。