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791.
以吐温/正丁醇/正已烷/水微乳液为介质,进行铝——铬天菁S的光度法测定,并用微机辅助试验,得到最佳增敏条件。结果表明,与水介质比较,提高了测定灵敏度,某些实验条件更为宽容,样品分析结果令人满意。  相似文献   
792.
介绍了一种实现导气式武器自动机反馈控制的技术,采用单片机组成了一套自动机后坐能量的闭环控制系统,建立了导气装置调节量与后坐能量关系的控制模型。实弹射击实验结果证明后坐能量可以自动稳定在预先拟定的数值上。  相似文献   
793.
寻找一个图是Hamilton图的充要条件一直是图论中不断探索的重要课题,本文对Hamilton问题进行了较深入的研究和讨论,给出了简单图是Hamilton图的若于判定定理及其证明。  相似文献   
794.
A new texture analysis approach by using Gibbs random field model is discussed. A parameter vector is defined in order to compute potentials of textures. It is found that texture features can be provided by its corresponding parameter vector, and the vector can be estimated in terms of maximum potential. Conclusions can be inferred that this new method based on the maximum potential is valid. Supported by the National Natural Science Foundation of China Zhang Zhan: born in 1971, Ph. D. graduate student  相似文献   
795.
Soft Systems Methodology is especially useful in diagnosing and addressing organizational problems and designing new systems in cultures that are characterised by pluralistic views and values. This paper demonstrates how SSM workshops in a large government agency resulted in a high level of creativity. SSM is then proposed as a methodology that could enhance group creativity in organizational design contexts.  相似文献   
796.
Increasingly knowledge has become a determining factor in achieving life’s potential and is the currency of the age. Without access to Information an individuals’ knowledge base cannot be enriched and without knowledge the individual becomes increasingly powerless. Advances in technology have provided opportunities for some to add to their stock of knowledge but access to sources of information is uneven and can lead to social unrest. The availability of information is an important factor in managing change and empowering citizens. The question about information and power then becomes one of ownership or sovereignty of the information. If we are to create an open society then we need to ensure that there is open access to knowledge through flexible and intelligent information systems that are available for all. In this paper we consider if we are truly entering the knowledge age or the age of ignorance.  相似文献   
797.
Arabidopsis thaliana, a model plant species, has a number of advantages over other plant species as an experimental organism due to many of its genetic and genomic features. The Chinese Arabidopsis community has made significant contributions to plant biology research in recent years[1,2]. In 2006, studies of plant biology in China received more attention than ever before, especially those pertaining to Arabidopsis research. Here we briefly summarize recent advances in Arabidopsis re-search in China.  相似文献   
798.
This paper proposes a method to formalize the interoperation in multi-domain environment. Through employing the algebra method, we conclude four types of the conflicts for the interoperation, and analyzes the cause of the policy conflicts. For each type of conflicts, we formalize it and proposes the method of detection and resolution. Finally, the method is illuminated be effective through comparing our work with others.  相似文献   
799.
在D3d晶场下利用Oh点群表象方法,构造了d6电子系的完全能量矩阵.使用全组态相互作用方法计算了RbFeCl3晶体中Fe2+的电子光谱和零场分裂因子,其计算结果与观测数据一致.  相似文献   
800.
The composite membranes with cellulose acetate (CA) as the separating layer material and polyacrylonitrile (PAN) as the supporting layer material were prepared for separating caprolactam (CPL) from CPL/water mixtures by pervaporation technique. The swelling experiments were carried out to investigate the effects of swelling time and CPL concentration on the degree of swelling. The results showed that the CA membrane reached swelling equilibrium within 24 h, and the degree of swelling first slightly decreased then increased with the increase of CPL concentration in the feed under the experimental conditions. Respectively comparing flux with permeance, and separation factor with selectivity, we found out that the separation performance of the CA/PAN composite membrane is more strongly dependent on its hydrophilic/hydrophobic nature as well as on the effects of operating parameters, such as feed composition concentration and feed temperature.  相似文献   
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