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王承忠 《理化检验(物理分册)》2010,(12):775-778,782
<正>1.2标准物质的期间核查1.2.1第一种方法有的标准物质如化学标样,可采用标样定值的方法进行期间核查。根据GB/T 15000.3-2008《标准样品工作导则(3)标准样品定值的一般原则和统计方法》,可有以下3种方法:①在一个实验室中用一种权威测定法或称为定义方、绝对测定法进 相似文献
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介绍了西维因、叶蝉散、呋喃丹三种农药标准物质的定值测定及均匀性、稳定性检验。实验方法为高效液相色谱法( H P L C)和差示扫描量热法( D S C)。三种农药标准物质纯度定值的不确定度为±02% 。 相似文献
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标准物质的定值就是赋予标准物质特性量值的过程,标准物质作为计量器具的一种,它能复现、保存和传递量值,保证在不同时间和空间下量值的可比性和一致性。对于比表面积标准物质,目前国内外还无法进行绝对方法测量。现阶段,国内外比表面积标准物质的定值过程均采用多家实验室协同定值的方法。本文以国家纳米科学中心研制的纳米级氧化铝比表面积标准物质为实例,对比表面积标准物质的定值过程以及不确定度评定进行了详细介绍。 相似文献
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《中国新技术新产品》2021,(17)
目前,由于继电保护引起的机组非计划停运仍然较多,保护定值设置不合理和电气二次回路存在的缺陷是造成继电保护不正确动作的主要原因,该文介绍了一种针对继电保护定值及回路现场系统性校验的全新方法,采用数字动态模拟技术的水电厂继电保护系统定值现地校核方法研究,丰富和完善了现有数字物理混合实时仿真装置在电厂的就地化应用,规范了电厂继电保护系统现地校验流程、试验内容、试验方法等,并利用电站年检机会,开展了保护定值及回路现场数字动态模拟校验,验证了该方法的可行性,为后续工程应用奠定了技术基础。 相似文献
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文章介绍了对20℃粘度分别为200Pa.s、500Pa.s及1000Pa.s的三种聚异丁烯高粘度标准液的牛顿性、粘度温度相关性、均匀性及稳定性的研究,及其粘度与密度定值方法的研究,并给出其定值结果。 相似文献
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客户关系管理与网络营销及其技术支持 总被引:1,自引:0,他引:1
客户关系管理、网络营销是当前企业赢得市场和客户的重要手段.本文在探讨客户关系管理和网络营销的基本原理和方法的基础上,探讨了两者集成的概念、方法和支撑手段. 相似文献
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工业研发项目的一体化持续风险管理方法 总被引:3,自引:1,他引:2
为了有效解决资源约束条件下的工业研发项目风险管理问题,提出了一体化持续风险管理框架,将传统的持续风险管理(CRM)的前三个阶段集成为一个新的风险设计阶段,并详细介绍了风险设计过程中所用到的技术和方法,为工业研发项目的风险管理提供了一个有效的管理工具. 相似文献
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Hsu-Hao Tsai 《Scientometrics》2011,87(3):425-450
There are few comprehensive studies and categorization schemes to discuss the characteristics for both data mining and customer
relationship management (CRM) although they have already become more important recently. Using a bibliometric approach, this
paper analyzes data mining and CRM research trends from 1989 to 2009 by locating headings “data mining” and “customer relationship
management” or “CRM” in topics in the SSCI database. The bibliometric analytical technique was used to examine these two topics
in SSCI journals from 1989 to 2009, we found 1181 articles with data mining and 1145 articles with CRM. This paper implemented
and classified data mining and CRM articles using the following eight categories—publication year, citation, country/territory,
document type, institute name, language, source title and subject area—for different distribution status in order to explore
the differences and how data mining and CRM technologies have developed in this period and to analyze data mining and CRM
technology tendencies under the above result. Also, the paper performs the K–S test to check whether the analysis follows
Lotka’s law. The research findings can be extended to investigate author productivity by analyzing variables such as chronological
and academic age, number and frequency of previous publications, access to research grants, job status, etc. In such a way
characteristics of high, medium and low publishing activity of authors can be identified. Besides, these findings will also
help to judge scientific research trends and understand the scale of development of research in data mining and CRM through
comparing the increases of the article author. Based on the above information, governments and enterprises may infer collective
tendencies and demands for scientific researcher in data mining and CRM to formulate appropriate training strategies and policies
in the future. This analysis provides a roadmap for future research, abstracts technology trends and facilitates knowledge
accumulations so that data mining and CRM researchers can save some time since core knowledge will be concentrated in core
categories. This implies that the phenomenon “success breeds success” is more common in higher quality publications. 相似文献
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Shuxiong Chen Diana H. Quan Gayathri Sam Victoria Ozberk Xiaonan T. Wang Peter Halfmann Manisha Pandey Michael F. Good Yoshihiro Kawaoka Warwick J. Britton Bernd H. A. Rehm 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(8):2205819
Immunogenic carrier proteins such as the non-toxic diphtheria toxin variant, cross-reacting material 197 (CRM197), are widely used in subunit vaccine formulations to boost immunogenicity of chemically conjugated antigens. Conjugate vaccines are inherently expensive due to laborious manufacturing steps. Here, this work develops a particulate vaccine platform based on using engineered Escherichia coli to assemble CRM197-antigen fusion proteins into discrete submicron-sized particles. This approach enables precise loading of diverse antigens and epitopes enhancing their immunogenicity. A cost-effective, high-yield, and scalable biomanufacturing process is developed. Purified particulate CRM197-antigen vaccines are ambient-temperature stable. CRM197 particles incorporating pathogen-specific antigens or epitopes from SARS-CoV-2, Streptococcus pyogenes (group A), and Mycobacterium tuberculosis induced cell-mediated and humoral immune responses mediating protective immunity in respective animal models of infection. The CRM197 particle vaccine platform is versatile, enabling co-delivery of selected antigens/epitopes together with immunogenic CRM197 as discrete stable particles avoiding laborious manufacture of soluble CRM197 and antigen followed by chemical conjugation. 相似文献
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An accurate and sensitive species-specific isotope dilution GC/ICPMS method was developed for the determination of trimethyllead (Me3Pb+) in biological and environmental samples. A trimethyllead spike was synthesized from 206Pb-enriched metallic lead by reaction of lead halide with methyllithium and subsequent formation of trimethyllead iodide. The isotopic composition of the spike solution was determined by GC/ICPMS after derivatization with tetraethylborate, and its concentration was determined by reverse isotope dilution analysis. The species-specific GC/ICP-IDMS method was validated by reference material CRM 605 (urban dust) certified for Me3Pb+. The method was also applied to determine the Me3Pb+ content in six biological reference materials (DORM 2, CRM 278, CRM 422, CRM 463, CRM 477, MURST-ISS-A2) and one sediment reference material (CRM 580) for which no certified values of this species exist. The Me3Pb+ concentrations in the biological reference materials vary in the range of 0.3-17 ng g(-1) (as Pb) except for the Antarctic Krill (MURST-ISS-A2), where the concentration was less than the detection limit of 0.09 ng g(-1), which was also found for the sediment. Up to 20% of total lead was methylated in the biological reference materials, whereas much higher methylation fractions were found for mercury. The method was also applied to seafood samples purchased from a supermarket with Me3Pb+ concentrations in the limited range of 0.3-0.7 ng g(-1). On the contrary, the portion of methylated lead in these samples varied over more than 2 orders of magnitude from 0.02 to 7.5%. 相似文献
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基于客户关系管理对于供应链的重要性,分析了供应链管理集成平台对客户关系管理系统的要求,在此基础上,建立了集成平台中客户关系管理系统的功能模型.针对客户关系管理系统中的数据分析需求,提出了一种基于数据仓库的客户关系管理系统解决方案. 相似文献
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决策支持在客户关系管理中的应用 总被引:2,自引:0,他引:2
客户关系管理是一种通过现代通讯技术和计算机技术,以有效满足客户的需求为目标来组织企业生产经营管理的一种信息系统。在客户关系管理中,决策支持的作用重要,必不可少。本文先介绍了客户关系管理的产生、发展以及在企业中的应用,然后讨论了决策支持在客户关系管理系统不同层次的应用,最后介绍了目前市场上的一些客户关系管理的产品。 相似文献