电弧螺柱焊机的电路分析

结合具体产品 ,对电弧螺柱焊机电路的组成和功能进行了分析 ,提供了常见故障原因及排除方法     

无机粉体的有机化改性及在橡胶中的应用

研究了用表面活性剂对无机粉体碳酸钙、钛白粉、白炭黑、凹凸棒土进行有机化改性的方法，制备了改性样品，测定了样品的比表面、接触角及在液体石蜡中的粘度等物化性能，还考察了带有反应性基团的新型阳离子表面活性剂（ＣＤＭＡＡＢ）所改性样品对天然橡胶力学性能的影响，结果表明，所述有机化改性是可行的。     

Immobilization of polyphenol oxidase on alginate–SiO2 hybrid gel: stability and preliminary applications in the removal of aqueous phenol

An organic/inorganic hybrid gel of alginate–SiO₂ (ALG–SiO₂) was used to immobilize the partially purified potato polyphenol oxidase (PPO) for the treatment of phenolic wastewater. The influences of alginate concentration, quantity of both enzyme and tetramethoxysilane (TMOS) on immobilization were investigated. The Michaelis constant for immobilized PPO was determined as 14.7 mmol L⁻¹ at 25 °C, and the highest activity of immobilized PPO was achieved at pH 7.0. The ALG–SiO₂ immobilized PPO was more stable than the free PPO or ALG(alone) immobilized PPO. This study suggests that ALG–SiO₂ immobilized PPO might be a potential tool for the removal of phenolic compounds from industrial wastewater. Copyright © 2008 Society of Chemical Industry     

试论煤炭工业可持续发展的涵义

对煤炭工业可持续发展定义进行了探讨，认为要准确界定其涵义，目前还面临许多不确定因素．从耗竭时间函数、代际公平配置和社会容忍程度的角度对有关不确定问题进行了分析，并给出了一种定义，研究了它涵盖的具体内容．     

Synthesis of needle-like aragonite from limestone in the presence of magnesium chloride

Needle-like aragonite was synthesized with a reversible solution reaction from limestone without calcinations. Scan Electron Microscope (SEM) and X-ray Diffraction (XRD) were used to characterize the morphology and the crystal structure of aragonite. The synthesis of aragonite whisker involves two steps. At first GCC (Ground Calcium Carbonate) was dissolved in an aqueous solution of magnesium chloride with reflux and air flush. Then CO₂ was bubbled into the suspension at a low temperature to produce aragonite whisker. An in-house designed reactor and acid–base titration analysis were used to measure the remaining GCC content in the reaction mixture. A kinetics equation of GCC dissolution was developed, which showed a first-order kinetic feature to magnesium chloride concentration. A reaction rate constant of 0.04234 h^?1 was obtained. The dissolution rate of GCC in magnesium chloride is much higher than that in the magnesium sulfate solution. Some aragonite whiskers with a length of ca. 20 μm and an aspect ratio of 8–12 can be synthesized.     

用现代生物技术改革生酒传统工艺的初探

该文主要探索了寿生酒传统工艺的改革，试验表明：当红曲用量减少40％，用真菌淀粉酶，黄酒活性干酵母取代，所酿制的寿生酒不仅品质更高，而且出酒率提高了5％左右。     

汽机第六段抽汽温度高的原因分析及处理

重点分析广州发电厂4台汽轮机第六段抽汽温度高的原因，并有针对性地进行系统改造，使机组运行的安全性、经济性得到提高。     

组合式频率合成器在HDTV接收机中的应用

在着重讨论ＤＤＳ／ＰＬＬ组合式频率合成器在各种结构形式及特点的基础上，研究了它在高清晰度电视接收机中的应用。     

An analysis and a dynamic testing method of microwave QPSK modulation

Using the clockwise or anticlockwise stepping pulse code signal, the characteristics of general quaternary phase shift keying (QPSK) modulation are analysed. This paper gives the spectrums in several operational conditions and the admittance formulas of related two modulation circuits. Several typical examples of QPSK modulation are calculated. The modulation effect and the phase error can be decided and the QPSK modulator under the dynamic test may be adjusted by using above results. The experimental results are in agreement with the theoretical calculations. An X-band QPSK modulator is also presented. The maximum phase error is less than 4°, the phase accuracy near ±0.1°, the insertion loss less than 4 dB and the data (transfer) rate up to 68 Mb/s.