On a Question of Phillips

In [5] Phillips proved that one can obtain the additive group of any nonstandard model *? of the ring ? of integers by using a linear mod 1 function h : F ?, where F is the α-dimensional vector space over ? when α is the cardinality of *?. In this connection it arises the question whether there are linear mod 1 functions which are neither addition nor quasi-linear. We prove that this is the case.     

同步荧光法测定食品中维生素B1

本文研究了食品中维生素Ｂ１的同步荧光法测定条件，采用氯化钾－乙醇作柱层析洗脱液，碱性介质中氧化后立即调为中性，并加入表面活性剂ＯＰ对体系增稳增敏，取代丁醇萃取，经济方便，用于几种粮食样品的测定，结果满意。     

用迁移率和载流子浓度研究碲镉汞中的深能级

获得了一种研究碲镉汞深能级的方法。通过分析迁移率 载子浓度与温度的关系，可以得到关于深能级的重要依据。     

CDMA基带信号发生器设计与仿真

主要研究了CDMA蜂窝通信系统的工作原理，且以基于IS－95标准的前向链路为主。利用MATLAB软件建立了前向链路中各器件的模块，实现了CDMA基带信号发生器，并在时域及频内进行了测量。     

一种E1与V.35信号转换的实现方法

E1 是我国和欧洲电信传输网一次群使用的传输标准，V.35 是我国数字数据网使用较多的一种接口标准。本文给出由DS2155 和DS2175 等芯片实现E1 接口与V.35 接口转换的方法。     

Resolution of Secondary α-Ketoalcohols Catalyzed by Lipase and Inversion of Stereochemistry

Several α-ketoalcohols of synthetic value were resolved using lipase as a catalyst. Lipoprotein lipase (LPL) provided the best rate of hydrolysis and kinetic differentiation. One of these optically pure α-ketoalcohol was converted to (5)-ibuprofen in good optical purity. The stereospecific inversion of (R)-alcohol to (S)-alcohol is described.     

弱1—凸对策及其解的性质

本文提出了一类特殊的ｎ人合作对策模型─—弱１—凸对策，研究了弱１—凸对策的解的性质，并证明弱１—凸对策的解满足所有常见的公理化特征．     

A branching process model for sand avalanches

An analytically solvable model for sand avalanches of noninteracting grains of sand, based on the Chapman-Kolmogorov equations, is presented. For a single avalanche, distributions of lifetimes, sizes of overflows and avalanches, and correlation functions are calculated. Some of these are exponentials, some are power laws. Spatially homogeneous distributions of avalanches are also studied. Computer simulations of avalanches of interacting grains of sand are compared to the solutions to the Chapman-Kolmogorov equations. We find that within the range of parameters explored in the simulation, the approximation of noninteracting grains of sand is a good one.     

Chalcogenide based all-solid-state thin electroplated ion-selective membrane for Hg(II) flow-injection determinations

The response to Hg(II) of a thin all-solid-state Te-doped silver chalcogenide membrane, described by the general formula Ag₂ + δSe_{1 − x}Te_x, which has been electrochemically prepared following a previously proposed approach, has been investigated. The kinetics of formation of the membrane's secondary dynamic response to Hg(II) has been successfully combined with the precise timing and transient signal, typical for flow-injection (FI) measurements, in developing a sensitive and reliable mercury FI detector. Under optimized stream conditions it exhibits a linear Nernstian response, with a double slope of the calibration graph of 59 mV dec⁻¹, over the mercury(II) concentration range 10⁻⁶ − 10⁻³ M, the typical sample throughput amounting to about 70 samples per hour. The observed chemical amplification of the signal is due to the specificity of the processes dominating the initial step in formation of the steady-state signal of the membrane to mercury. The analytical performance of the Hg(II) FI detector, as regards sensitivity, reproducibility, selectivity and long-term stability has been thoroughly investigated. The exact procedure for membrane electrodeposition is given and the potential of the proposed approach as a cost-effective way for preparing chalcogenides of unique structure and properties has been outlined in the above context.