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61.
For any -complexes and , we show that . We use this fact to compute generalized evaluation subgroups of generalized tori relative to a sphere.
62.
一种包覆型聚合物高效液相色谱固定相的制备与评价 总被引:1,自引:1,他引:1
当代应用最广的HPLC固定相中,硅胶基质填料化学稳定性较低,并且由于残存硅羟基而表现所谓第二效应,特别使碱性化合物的峰形拖尾;聚合物基质填料虽提高了化学稳定性,没有离子基团,但刚性降低,并且由于溶胀难于进行梯度淋洗;面包覆型聚合物填料则可综合二者的优点,本文对我们制备的这种固定相作初步报道。 相似文献
63.
按照GB/T5009.29-2003中山梨酸含量测定方法,对测量结果的不确定度来源如标准溶液浓度、校准曲线参数、样品稀释等进行了分析,对各不确定度分量进行了评定和量化。气相色谱法测定酱油中山梨酸相对扩展不确定度为0.56%。 相似文献
64.
超细碳氮化钛的分析和评估 总被引:3,自引:1,他引:3
采用多种技术对超细碳氮化钛进行组成分析。可分别测定吸附和化合状态的氧。晶格常数与(原子比)具有线性关系,表明碳与氮可以相互无限置换,分子式为Ti C_xN_(1-x),每一样品只有一种C/N比.固溶体是均质的。气相合成的碳氮化钛含微量杂质,包括游离碳和氯根等,主相量显著地受吸附氧量影响,可控制达97%以上。介绍了拟定的分析方法。 相似文献
65.
Medical laboratories of the public sector as well as of the private sector on the island of Mauritius are preparing for accreditation. The clinical laboratory of the Central Health laboratory of the Ministry of Health and Quality of Life has undergone a pre-assessment by experts of the International Atomic Energy Agency (IAEA) through the aegis of a project targeted to members of the Africa Region. Several shortcomings were identified and respective corrective actions were recommended for implementation within a given time frame. In addition to ensuring the competence of the laboratory, accreditation has various positive aspects such as an increased awareness of the staff to quality and better training opportunities. The pre-assessment exercise has provided a gap analysis, which is an important aspect in the preparation towards accreditation. 相似文献
66.
This paper applies discrete wavelet transform (DWT) with various protein substitution models to find functional similarity of proteins with low identity. A new metric, 'S' function, based on the DWT is proposed to measure the pair-wise similarity. We also develop a segmentation technique, combined with DWT, to handle long protein sequences. The results are compared with those using the pair-wise alignment and PSI-BLAST. 相似文献
67.
J. Forstén 《Accreditation and quality assurance》1998,3(7):285-288
This article mainly focuses on the testing of products, materials, etc., but the general principles are applicable in a broader
perspective. Quality of testing should be judged based on fitness for purpose. This judgement includes both objective and
subjective elements. The possibility to make decisions and other professional judgements based on test results alone is discussed
and compared with the decisions and judgements being made through the certification and inspection process. Quality, including
the uncertainty of the test results, depends on many factors, and in order to make necessary improvements in the testing procedures
based on the customers' needs, the right issues should be addressed. The question arises as to whether, in laboratories' quality
systems and in the accreditation and certification process, attention is really paid to those factors that are crucial to
obtaining reliable results. 相似文献
68.
R. Mathur-De-Vré 《Accreditation and quality assurance》1997,2(2):63-68
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
69.
Stephen de Mora Jean-Pierre Villeneuve Eric Wyse 《Accreditation and quality assurance》2007,12(11):587-592
Aspects of the International Atomic Energy Agency (IAEA) Analytical Quality Control Services (AQCS) for marine environmental
studies are discussed, focusing on recent laboratory performance studies (LPS) and the production of reference materials for
trace metals and organic compounds in various marine matrices. The IAEA has organized seventeen global interlaboratory studies
for a range of organic contaminants. Of note has been the inclusion of numerous polychlorinated biphenyl congeners (PCBs)
and some sterols of anthropogenic origin. Concurrently, there have been eleven worldwide intercomparison exercises for trace
metals in the marine environment, most of which included methylmercury. Although such interlaboratory studies can help improve
performance in individual laboratories and regional laboratory networks, the results reveal that problems remain in the determination
of some metals and many organic contaminants. 相似文献
70.
D. Joe Boone 《Accreditation and quality assurance》2004,10(1-2):5-9
A recent US Institute of Medicine report indicated that up to 98,000 deaths and more than 1 million injuries occur each year in the United States due to medical errors. These include diagnostic errors, such as an error or delay in diagnosis, failure to employ indicated tests and the use of outmoded tests. Laboratory tests provide up to 80% of the information used by physicians to make important medical decisions, therefore it is important to determine how often laboratory testing mistakes occur, whether they cause patient harm, where they are most likely to occur in the testing process, and how to prevent them from occurring. A review of the literature and a US Quality Institute Conference in 2003 indicates that errors in laboratory medicine occur most often in the pre-analytical and post-analytical steps in the testing process, but most of the quality improvement efforts focus on improving the analytical process. Measures must be developed and employed to reduce the potential for mistakes in laboratory medicine, including better indicators for the quality of laboratory service. Users of laboratory services must be linked with the laboratorys information system to assist them with decisions about test ordering, patient preparation, and test interpretation. Quality assessment efforts need to be expanded beyond external quality assessment programs to encompass the detection of non-analytical mistakes and improving communication between the users of and providers of laboratory services. The actual number of mistakes in laboratory testing is not fully recognized, because no widespread process is in place to either determine how often mistakes occur or to systematically eliminate sources of error. We also tend to focus on mistakes that result in adverse events, not the near misses that cause no observable harm. The users of laboratory services must become aware of where testing mistakes can occur and actively participate in designing processes to prevent mistakes. Most importantly, healthcare institutions need to adopt a culture of safety, which is implemented at all levels of the organization. This includes establishing closer links between providers of laboratory services and others in the healthcare delivery system. This was the theme of a 2003 Quality Institute Conference aimed at making the laboratory a key partner in patient safety. Plans to create a permanent public–private partnership, called the Institute for Quality in Laboratory Medicine, whose mission is to promote improvements in the use of laboratory tests and laboratory services are underway.Presented at the 9th Conference on Quality in the Spotlight, 18–19 March 2004, Antwerp, Belgium. 相似文献