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1.
 There is growing interest in developing a general strategy and quality standards for possible accreditation or certification of R&D laboratories. This article discusses the scope and limitations of Quality Systems in R&D activities. The extension of QA to R&D centres in general requires emphasis on project management and scientific competence in addition to quality management and technical competence. Received: 11 September 1996 Accepted: 13 November 1996  相似文献   
2.
The metabolic profiling of kiwifruit (Actinidia deliciosa, Hayward cultivar) aqueous extracts and the water status of entire kiwifruits were monitored over the season (June-December) using nuclear magnetic resonance (NMR) methodologies. The metabolic profiling of aqueous kiwifruit extracts was investigated by means of high field NMR spectroscopy. A large number of water-soluble metabolites were assigned by means of 1D and 2D NMR experiments. The change in the metabolic profiles monitored over the season allowed the kiwifruit development to be investigated. Specific temporal trends of aminoacids, sugars, organic acids and other metabolites were observed.The water status of kiwifruits was monitored directly on the intact fruit measuring the T2 spin-spin relaxation time by means of a portable unilateral NMR instrument, fully non-invasive. Again, clear trends of the relaxation time were observed during the monitoring period.The results show that the monitoring of the metabolic profiling and the monitoring of the water status are two complementary means suitable to have a complete view of the investigated fruit.  相似文献   
3.
严晓光 《电子质量》2005,(2):46-46,34
通过在信息化行业中QA和QC的定义和区别,论述QA和QC的主要工作内容,对企业QA和QC部门的分工有一定的借鉴作用。  相似文献   
4.
采用低能电子衍射、扫描隧道显微镜、第一性原理密度泛函理论计算以及分子力学计算,分别对不同烷基链取代的喹吖啶酮(QA)分子在Ag(110)基底上的吸附和生长进行了研究.QA和Ag基底的相互作用主要来自分子中O原子和Ag基底的共价键,它决定了分子的取向和最优吸附位置;而烷基链决定了分子吸附层的取向,QA分子间的排列可以通过烷基链的长度来调节.由此借助调节烷基链的长度,能够可控地制备具有不同物理性质的单层分子薄膜.  相似文献   
5.
Analytical methods for the analysis of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) are widely available and are the result of a vast amount of environmental analytical method development and research on persistent organic pollutants (POPs) over the past 30–40 years. This review summarizes procedures and examines new approaches for extraction, isolation, identification and quantification of individual congeners/isomers of the PCBs and OCPs. Critical to the successful application of this methodology is the collection, preparation, and storage of samples, as well as specific quality control and reporting criteria, and therefore these are also discussed. With the signing of the Stockholm convention on POPs and the development of global monitoring programs, there is an increased need for laboratories in developing countries to determine PCBs and OCPs. Thus, while this review attempts to summarize the current best practices for analysis of PCBs and OCPs, a major focus is the need for low-cost methods that can be easily implemented in developing countries. A “performance based” process is described whereby individual laboratories can adapt methods best suited to their situations. Access to modern capillary gas chromatography (GC) equipment with either electron capture or low-resolution mass spectrometry (MS) detection to separate and quantify OCP/PCBs is essential. However, screening of samples, especially in areas of known use of OCPs or PCBs, could be accomplished with bioanalytical methods such as specific commercially available enzyme-linked immunoabsorbent assays and thus this topic is also reviewed. New analytical techniques such two-dimensional GC (2D-GC) and “fast GC” using GC–ECD may be well-suited for broader use in routine PCB/OCP analysis in the near future given their relatively low costs and ability to provide high-resolution separations of PCB/OCPs. Procedures with low environmental impact (SPME, microscale, low solvent use, etc.) are increasingly being used and may be particularly suited to developing countries. Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users.  相似文献   
6.
鱼肉组织中多溴联苯醚的定量分析   总被引:9,自引:0,他引:9  
多溴联苯醚(PBDEs)是一类广泛用于家用电器、电子产品、塑料泡沫、家居装饰材料等行业的添加型阻燃剂[1],使用量最多的是五溴联苯醚(penta-BDE),八溴联苯醚(octa-BDE)和十溴联苯醚(deca-BDE)3种[2]。最近的研究表明[4-6],多溴联苯醚已广泛地存在于各种环境介质、生物体及人体中  相似文献   
7.
彭文忠 《电子质量》2002,(12):71-72
本文介绍具有通信行业特点的TL9000标准,特色是坚持以顾客为关注点,培育有效和高效保护电信产品的完整性和使用性的质量管理体系。  相似文献   
8.
9.
基于约束的自然语言问题到OWL的语义映射方法研究   总被引:2,自引:1,他引:1       下载免费PDF全文
高明霞  刘椿年 《电子学报》2007,35(8):1598-1602
OWL已经成为重要的知识表示和交换方式.OWL驱动的问答系统是比搜索引擎更具挑战性的研究.本文致力于解决为自然语言问题获取正确的OWL解释.考虑到问题理解的复杂性,影响因素的多样性,本文提出一种基于约束的语义映射方法.该方法分解问题成为变量,索引OWL知识成为变量域,抽象约束形成函数.并建立了目标函数完成问题变量在候选OWL知识库中获取合理解释的过程.该方法基于网络智能研究院知识库和问题集进行了初步评估.实验结果表明:和传统基于关键字匹配的算法比较,本文提出的方法使可解释问题比例增加了18%左右.  相似文献   
10.
EURADOS Working Group 2 (WG2) on Harmonization of Individual Monitoring is a network of individual monitoring services (IMSs) that aims to promote quality, technical excellence and good practice in European Member States. To help to improve quality, in 2012 EURADOS WG2 carried out a survey of IMSs in Europe. The survey was sent to about 170 IMS and included questions on: the use of formal quality assurance (QA) standards, QA in dosimetry, matters of practice, and common sources of error. The present paper summarises the main findings of the survey, and compares them with those of an earlier study (2003). The survey found that profile of QA is high amongst the responding IMSs, and that most are following good practice. A majority of services comply with formal quality standards and good attention is paid to traceability, method validation and proficiency testing. There are some areas where lessons can be learned, for example in the assessment of measurement uncertainty; and it remains very instructive to see what the main causes of error are for IMSs in general.  相似文献   
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