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791.
论述了引进ISO9001国际标准.健全质量保证体系,重视质量文件.强针质量监督与考核机制.从而提高企业在国际市场竞争力的做法与经验.  相似文献   
792.
This paper describes the change in a researcher's practices from one of studying regional industrial development at a distance to one of working closely with a network of agri-food managers. This is accompanied by a discussion of the methodological and theoretical possibilities for an action research inspired economic geography. Some of the core characteristics of a pragmatic conceptualization of action research are revised. It is argued that theoretical developments within economic geography make possible a dialogue between researchers and local actors and that economic geography is challenged to accept that knowledge is generated through such a dialogue. Attempts to create a dialogue between action research and economic geography in a specific Norwegian industrial and geographical context are described. These attempts indicate that the researcher's methodological approach has been transformed from a narrow one relying solely on conventional social science methods to a broader one including participatory action research.  相似文献   
793.
Activities of trimalonic acid fullerene (TMA C_60) on DNA restrictive enzymatic reaction were investigated by using two restrictive endonucleases Hind III and EcoR I and plasmid pEGFP-N1 with single restric-tive site for both enzymes. Meanwhile, TMA C60 was also tested to clarify its effects on polymerase chain reaction (PCR) with the catalyst of Taq DNA polymerase and the template of plasmid pEGFP-N1. The products from restrictive reactions or PCR were detected by agarose gel electrophoresis. It was found that the product amounts from restrictive reactions or PCR decreased significantly with addition of TMA C60. The inhibition by TMA C60 was dose-dependent and IC50 values for reactions of Hind III, EcoR I and PCR were 16.3, 6.0 and 6.0 μmol/L, respectively. Addition of two scavengers of reactive oxygen species (ROS), L-ascorbic acid-2-phosphate ester magnesium and sodium azide at the con-centrations of 2―10 mmol/L did not antagonize the activities of TMA C60 against PCR and two restrictive reactions. However, increase of Taq DNA polymerase amounts in PCR system antagonized the activities of TMA C60. These data implied that TMA C60 was able to inhibit the activities of the three above-mentioned enzymes involved in DNA metabolism, and that this inhibition probably did not correlate to ROS.  相似文献   
794.
Literature has increasingly been seen as a text in a context. And text is a particular embodiment of the abstract idea that a work tries to exhibit. The textual condition of a publication involves not only the author but also the editor, publisher and readers. Text varies because of its ever-changing textual condition. Since its first publication in 1813, Jane Austen's novel Sense and Sensibility had been reproduced several times in the 19th century. The analysis of the novel's text and textuality in a way ...  相似文献   
795.
在科技管理系统中,县级科技管理部门属于最基层的工作机构,是科技管理的基础环节,而基层科技工作在大力推进科技进步.实现科教兴国战略中具有独特的地位,对县域经济发展、社会进步起着极其重要的作用,掌握基层科技工作的现状,弄清工作中存在的问题,并探索其解决的途径具有重要意义  相似文献   
796.
本文介绍的求闭环频率特性的图解法,其特点是不用Nichols图线或等M圆、等N圆图,而是通过向量叠加的办法,由开环频率特性求闭环频率特性。该方法计算量少,简单方便,适用于自动控制系统的分析与设计。  相似文献   
797.
This review presents the scintillators requirements for the medical imaging modalities. The history and the development in recent years of the medical scintillators (mainly for GSO:Ce, LSO:Ce, LuAP:Ce) are expatiated in detail.  相似文献   
798.
苄基环戊二烯的相转移催化合成   总被引:1,自引:0,他引:1  
碱性不介质中和四丁基溴化铵存在下,环戊二烯和氯化苄反应,合成了苄基环戊二烯。  相似文献   
799.
本文介绍了用三甲氧基硅烷与甲基丙烯酸烯雨酯合成甲基丙烯酸-3-(三甲氧基硅基)丙酯的一种方法。  相似文献   
800.
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