The elimination of fast variables in complex chemical reactions. III. Mesoscopic level (irreducible case)

The master equation for a complex chemical reaction cannot always be reduced to a simpler master equation, even if there are fast and slow individual reaction steps. Nevertheless the elimination of intermediates can be carried out with the help of the-expansion. This is illustrated with a well-known complex reaction: the dissociation of N₂O₅. It is shown that the intrinsic fluctuations in the N₂O₅ decay are larger than those implied by the master equation suggested by the macroscopic rate law.     

冲击波处理的结晶MgO的化学分析正电子谱研究

冲击波处理的结晶ＭｇＯ的化学分析正电子谱研究＊张菊郑小明（杭州大学催化研究所，杭州３１００２８）常志向（抚顺石油化工研究院，抚顺１１３００１）关键词冲击波，化学分析正电子谱，结晶氧化镁，丁烯，脱氢冲击波是在介质中以超音速传播的压力脉冲．气体中的冲击波...     

聚中性红膜修饰电极的电化学特性及其电催化性能

研究了中性红在玻碳电极表面电聚合成膜的方法和条件，对膜内电荷传输过程和电化学特性分别用循环伏安技术和电位阶跃暂态技术进行了初步探讨。该膜对维生素Ｃ和亚硝酸盐有较强的电催化作用，催化电流与底物浓度在很宽的范围内呈线性关系，可用于实际样品的分析。     

Monotone Chemical Reaction Networks

We analyze certain chemical reaction networks and show that every solution converges to some steady state. The reaction kinetics are assumed to be monotone but otherwise arbitrary. When diffusion effects are taken into account, the conclusions remain unchanged. The main tools used in our analysis come from the theory of monotone dynamical systems. We review some of the features of this theory and provide a self-contained proof of a particular attractivity result which is used in proving our main result.     

碳纳米管的化学修饰研究进展

介绍了近年来碳纳米管化学修饰(共价修饰和非共价修饰)方面的最新进展。参考文献47篇。     

三七水溶性化学成分及其药理研究新进展

综述了近年来三七水溶性化学成分及其药理作用特别是对神经生理活性研究的进展，对三七与人参展其它植物植物进行了比较，阐明了三七所含多肽哆肽成分研究的意义及可行性。     

无相移滤波技术用于分析化学信号处理

把无相移滤波技术引入了分析化学信号处理领域。其方法为：先将输入序列按顺序滤波，然后将所得结果逆转后反向通过滤波器，再将所得结果逆转后输出。通过对色谱信号的实验研究表明，与普通的数字滤波方法相比较，无相移滤波不但具有普通数字滤波的优点，而且不会产生滤波前后的相位偏移，具有良好的应用前景，尤其对于需要准确计算保留时间的场合，用此预处理方法非常适合。     

毛蕊杜鹃挥发油化学成分研究

毛蕊杜鹃(Rhododendron tubulosum Ching ex wang wei-yei)系杜鹃花科杜鹃花属植物,分布于四川、西藏、甘肃和青海,其中青海分布最广,藏民常作为单方草药用于治疗肺炎和老年慢性气管炎,具有镇咳、祛痰作用,本文用自制的同时水汽蒸馏-溶剂萃取装置,从采自青海玉树州的毛蕊杜鹃鲜叶和嫩枝提取挥发油,用毛细管气相色谱-质谱和Kovats指数双重定性法对     

LC-MS/MS method for the confirmatory determination of aromatic amines and its application in textile analysis

A confirmation method for the determination of 18 aromatic amines originating from azo dyes after reductive cleavage was developed. The method is based on the use of high-performance liquid chromatography/tandem mass spectrometry with atmospheric-pressure chemical ionization. For the identification of the analytes one precursor ion and two daughter ions (multi-reaction monitoring, MRM) were selected and the LC-MS/MS parameters optimized to obtain high sensitivity and selectivity. The linear ranges varied from 0.1–1 to 30–50 g mL^–1 with correlation coefficients of 0.99 or better. The applicability of the method to determine o-tolidine (3,3-dimethylbenzidine) and 3,3-dimethoxybenzidine in textiles following reductive cleavage of acid red 114, trypan blue, and Chicago sky blue 6B was demonstrated.     

Process study of thermal plasma chemical vapor deposition of diamond,part II: Pressure dependence and effect of substrate pretreatment

The effect of pressure during thermal plasma chemical vapor deposition of diamond films has been investigated for a pressure range from 100 to 760 Torr. The maximum growth rate in our experiments occurs at 270 Torr for substrate temperatures around 1000°C. The existence of an optimum pressure for diamond deposition may he related to the balance between generation and recombination of atomic hydrogen and carbon-containing active species in front of the substrate. To estimate the concentrations of atomic hydrogen and methyl radicals under thermal plasma conditions, calculations based on thermodynamic equilibrium have been performed. This approximate evaluation provides useful guidelines because rapid diffusion results in a near frozen chemistry within the boundary layer. The effect of substrate pretreatment on diamond deposition depends on the type of substrate used. Two growth modes have been observed-layer growth and island growth of diamond crystals on various substrates. Screw dislocations have been observed in diamond deposition in thermal plasmas, and defects such as secondary nucleations are more concentrated along (III) directions than along (100) directions.