Study on peak overpressure and flame propagation speed of gas deflagration in the tube with obstacles

The on-way peak overpressure and flame propagation speed of gas deflagration in the tube with obstacles are important data for process safety. Based on carbon monoxide deflagration experiments, the paper presents a multi-zone integration model for calculation of on-way peak overpressure, in which the tube with obstacles is considered as a series of venting explosion enclosures which link each others. The analysis of experimental data indicates that the on-way peak overpressure of gas deflagration can be correlated as an empirical formula with equivalence ratio of carbon monoxide oxidation, expansion ratio, flame path length, etc., and that the on-way peak overpressure exhibits a linear relationship with turbulence factor and flame propagation speed. An empirical formula of flame propagation speed is given.

基于ADO的数据库编程及应用

介绍了如何利用ADO(ActiveX Data Object)接口连接和操作不同的数据库。并给出了在Visual C++.net环境下ADO结合SQL访问数据库的程序代码。

Radiative electron capture and subsequent radiative decay in collisions of U89+ ions with N-2

To evaluate the radiative electron capture for the collisions of U89+ ion with N-2, radiative recombination cross sections and the corresponding emitted photon energies are calculated from the ground state 1s(2)2s to 1s(2)2snl(j) (2 <= n <= 9, 0 <= l <= 6) using the newly developed relativistic radiative recombination program RERR06 based on the multiconfiguration Dirac-Fock method. The x-ray spectra for radiative electron capture in the collision have been obtained by convolving the radiative recombination cross sections and the Compton profile of N2. Good agreement is found between the calculated and experimental spectra. In addition, the transition energy levels and probabilities among the 147 levels from the captured 1s(2)2snl(j) have been calculated. From the calculated results, radiative decay cascade processes followed by the radiative electron capture have also been studied with the help of multistep model and coupled rate equations, respectively. The present results not only make us understand the details of the radiative electron captures and the radiative decay cascade spectra in the experiment but also show a more efficient way to obtain the cascade spectra. Finally, the equivalence between the multistep model and coupled rate equations has been shown under a proper condition and the latter can hopefully be extended to investigate other cascade processes.

HIRFL控制系统数据库系统设计

HIRFL（兰州重离子加速器）是我国第一个大型重离子物理研究装置。HIRFL控制系统是保证HIRFL系统正常高效运转的重要环节。本文利用数据库技术、网络技术设计了HIRFL控制系统数据库系统，实现了在网络环境中只使用一个应用程序就可对整个HIRFL系统控制进行控制的要求。论文首先介绍了数据库系统理论，然后对软件设计涉及的各部分基础知识进行了阐述，最后详细讨论了整个数据库系统设计中的数据库设计、应用程序人机界面设计等部分。数据库应用SQL Server 2000大型数据库，并使用ODBC技术作为数据库访问手段；人机界面部分使用面向对象编程技术进行Windows编程。整个论文工作在建立了一个包含整个控制系统各部分设备信息的数据库的同时，还提供了一套包含所有基本控制功能的HIRFL分布式控制软件，为HIRPL控制系统数据库系统的进一步完善提供了二次开发平台。

zero point of charge of cupric hydroxide and surface area determination by dye adsorption

zero point of charge of freshly precipitated cu(oh)2 has been determined to lie at pH 7.7 by means of microclectrophoresis technique. Day aged hydroxide shows an acid zpc shift to pH 7.3. these experimental values approximate the equivalence points of cu+ and oh_ ,which can be estimated from the solubility diagram constructed fo gu(oh)2 and cuo.

生成诊断公式的有限状态进程等价验证

分析有限状态进程互模拟等价判定技术,探讨了诊断公式的生成问题。给出了将有限状态进程转化为带标号的迁移系统,修改了Paige和Trajan求解最粗划分的算法,使其适用于带标号的迁移系统。给出生成Hennessy-Milner逻辑描述的诊断公式的算法,当两个进程不能互模拟时,产生两个诊断公式。算法的时间复杂度为O(mlogn),空间复杂度为O(m+n)。

空间数据管理与维护系统设计

空间数据管理和维护技术是卫星数据应用系统的关键技术之一，对于推动卫星数据应用的发展有不可或缺的重要意义。本文在分析数据管理的各种先进技术的基础上，设计了卫星地面应用系统中的数据管理维护解决方案；讨论了该解决方案的具体设计实现。主要工作有：一、 系统架构：本文设计了层次式的系统架构，将系统从上到下分为数据应用层、数据访问接口层、逻辑数据层、物理数据层等，并对各层之间的功能和之间的交互做了明确定义。二、 数据统一访问：本文设计了数据访问接口层，向下层负责操作逻辑数据，向上层用户提供一个易用的统一的数据访问接口。该接口层屏蔽了底层数据格式和存储等差异，支持数据的统一存取，提供透明的数据访问，降低了系统之间的耦合度。三、 数据操作实现：本文基于XML设计了数据用户和数据管理维护系统之间数据交换的格式。在数据访问接口层实现了从XML格式请求到SQL语句（或文件API调用）的转换逻辑以实现各种数据操作请求，提高了系统可扩展性。论文还设计了多种数据安全方法相结合的数据安全策略，提高了系统中数据的安全性。数据管理维护系统的开发和测试过程表明，该方案基本满足卫星地面应用系统中数据管理和维护的需求。

Research on storing raster metadata in spatial database

Storage of raster metadata is a key topic in spatial database. Although there are a few of abstract standards on raster metadata, there is not implement standard about it. This paper concludes three storage models implemented in current spatial databases and discusses their advantages and disadvantages. After that analyzing, the paper proposes a mixed storage method which is used the relational table to store structured metadata and used XML to store non-structured metadata, and gives its implementation solution. © 2010 IEEE.

Relaxation time and conductivity of comb-like gel polymer electrolytes

Using the copolymer of acrylonitrile (AN), methyl methacrylate (MMA), and poly(ethylene glycol) methyl ether methacrylate as a backbone and poly(ethylene glycol) methyl ether (PEGME) with 1100 molecular weight as side chains, comb-like gel polymers and their Li salt complexes were synthesized. The dynamic mechanical properties and conductivities were investigated. Results showed that the gel copolymer electrolytes possess two glass transitions: alpha-transition and beta-transition. Based on the time-temperature equivalence principle, a master curve was constructed by selecting T. as reference temperature. By reference to T-0 = 50 degrees C, the relation between log c, and c was found to be linear. The master curves are displaced progressively to higher frequencies as the content of plasticizer is increased. The relation between log tau(p) and the content of plasticizer is also linear.

Mechanical relaxation time of comblike polymer electrolyte

Using poly(styrene-co-maleic anhydride) as the backbone and poly(ethylene glycol) methyl ether as side chains,three kinds of comblike polymers of different side chain length were synthesized. The Li-salt complexes and their firms were prepared. The dynamic mechanical properties were investigated. It was found that the main chain was rigid and the side chain was flexible in this comblike polymer system. Based on the time-temperature equivalence principle, a master curve was constructed. By selecting T-alpha as reference temperature, Arrhenius plots of shift factor and iso-free-volume plots were attained. The values of WLF parameters C-1 and C-2 increase with increasing salt concentration. By reference to T-0 = 50 degrees C, the relation between the average relaxation time 1g tau(c) and Li-salt concentration C is linear. The master curves are displaced progressively to higher frequencies as the M-w of side chains is increased. The relation between the average relaxation time 1g tau(n) and M-w of side chains is also linear. And the master curves are movable with the change of salts. It shows the effect of different kinds of salt on relaxation time.

Study of the conductivity and side chain mobility of a comb-like polymer electrolyte using the dynamic mechanical method

Using poly(styrene-co-maleic anhydride) as a backbone and poly(ethylene glycol) methyl ether (PEGME) with different molecular weights as side chains, three comb-like polymers and their Li salt complexes were synthesized. The dynamic mechanical properties and conductivities were investigated. Results showed that the polymer electrolytes possess two glass transitions: alpha -transition and beta -transition, and the temperature dependence of the ionic conductivity shows WLF (Williams-Landel-Ferry) behavior. Based on the time-temperature equivalence principle, a master curve was constructed by selecting T-beta as reference temperature. The values of the WLF parameters (C-1 and C-2) were obtained and were found to be almost independent of the length of the PEGME side chain and the content of Li salt. By reference to T-0 = 50 degreesC. the relation between log tau (c) and c was found to be linear. The master curves are displaced progressively to higher frequencies as the molecular weight of the side chain is increased. The relation between log tau (n) and the molecular weight of the side chain is also linear. (C) 2001 Elsevier Science B.V. All rights reserved.