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The use of inductively coupled plasma mass spectrometry (ICP-MS) in the production of environmental certified reference materials by the National Research Council of Canada is reviewed. Particular emphasis is placed on the use of isotope dilution ICP-MS. Results for fresh and saline natural waters, fish tissues and sediments are presented to illustrate the impressive capabilities of this technique. 相似文献
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Narukawa T Chiba K Kuroiwa T Yarita T Takatsu A 《Analytical and bioanalytical chemistry》2007,389(2):661-666
An arsenobetaine [(CH3)3As+CH2COO−] solution reference material, NMIJ CRM 7901-a, intended for use in the speciation of arsenic compounds, was developed and
certified by the National Metrology Institute of Japan (NMIJ), part of the National Institute of Advanced Industrial Science
and Technology (AIST). The high-purity arsenobetaine powder was synthesized from trimethylarsine [(CH3)3As], and it was dissolved in water in order to prepare 20 mg kg−1 of arsenobetaine standard solution. The solution was bottled in 500 bottles (each containing 10 ml). Certification of the
CRM for arsenobetaine was conducted by NMIJ. The concentration of As was determined by four independent analytical techniques
(ICP–MS, ICP–OES, GFAAS and LC–ICP–MS), and each result was converted to the arsenobetaine concentration by applying an appropriate
factor. The arsenobetaine concentration in the CRM was thus certified. 相似文献
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This article describes the views of IRMM on accreditation of CRM producers and the philosophy which is behind these views.
More specifically, it explains the reasons for choosing ISO Guide 34 rather than ISO/IEC 17025 as the basis document for the
proposed accreditation of its CRM activites.
Received: 27 May 2002 Accepted: 11 July 2002
Acknowledgements Information on accreditation programmes in Australia and USA provided by Maree Stuart (NATA) and Randall V. Querry (AL2A)
is greatly acknowledged.
Correspondence to J. Pauwels 相似文献
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对一级军用标准物质JBWY05901钨合金标准物质稳定性检验的化学分析方法进行了比较选择,提出了该标准物质稳定性检验方法,给出了检验数据的统计处理方法及稳定性检验结果。 相似文献
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Sharpless KE Greenberg RR Schantz MM Welch MJ Wise SA Ihnat M 《Analytical and bioanalytical chemistry》2004,378(5):1161-1167
Well-characterized reference materials are needed by laboratories in the food testing and nutrition communities to facilitate compliance with nutritional labeling laws, to provide traceability for food exports needed for acceptance in many foreign markets, and to improve the accuracy of nutrition information that is provided to assist consumers in making sound dietary choices. As a result of the enactment of the Nutrition Labeling and Education Act of 1990 and the Infant Formula Act of 1980, the National Institute of Standards and Technology (NIST) has developed a suite of food-matrix Standard Reference Materials (SRMs) characterized for nutrient concentrations. These include SRM 1544 Fatty Acids and Cholesterol in a Frozen Diet Composite, SRM 1546 Meat Homogenate, SRM 1548a Typical Diet, SRM 1566b Oyster Tissue, SRM 1846 Infant Formula, SRM 1946 Lake Superior Fish Tissue, SRM 2383 Baby Food Composite, SRM 2384 Baking Chocolate, SRM 2385 Spinach, and SRM 2387 Peanut Butter. Many of these materials were developed at the request of the food industry to populate a nine-sectored fat-protein-carbohydrate triangle developed by AOAC International. With the completion of SRM 2387, SRMs representing each sector of the triangle are now available. These food-matrix reference materials are intended primarily for validation of analytical methods for the measurement of proximates, fatty acids, vitamins, minerals, and so on in foods of similar composition. They may also be used as "primary control materials" in the value-assignment of in-house, secondary, control materials to confirm accuracy as well as to establish traceability to NIST. 相似文献
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Eddie A. Maier Bernard Griepink Philippe Quevauviller Luciano De Angelis Herbert Muntau 《Mikrochimica acta》1990,102(1-3):87-99
Analyses of nutritive elements are routinely performed in grass or hay for animal feed in order to improve the state of health and growth of domestic animals. To control the quality of such determinations, the Community Bureau of Reference (BCR) so far has produced two certified reference materials: Hay Powder (CRM 129) and Rye Grass (CRM 281). After a careful preparation procedure of the materials, a homogeneity study and a long-term stability study, the contents of the elements Ca, K, Mg, P, S, Zn, I, N and Kjeldahl-N were certified in CRM 129, whereas CRM 281 was certified for As, B, Cd, Cu, Hg, Mn, Mo, Ni, Pb, Sb, Se and Zn. This paper presents the certification exercise and especially concentrates on the elements I, B and Mo as examples of analytical work. Indicative values for Co, Cr, Fe, Cl and Na were also obtained. 相似文献
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论述了乙烯、丙烯中多元标准混合气体气相色谱分析方法,给出了分析条件及方法的相对标准偏差,并就该标准气体配制的均匀性、稳定性的变化结果进行了分析与考察,同时对标准气体的性能及不确定度进行了评价。 相似文献
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Fourteen organic compounds, 1-pentene, 2-methylbutane, 2-methyl-1,3-butadiene (isoprene),n-pentane, 2-chloropropane, ethyl alcohol, 2,2,4-trimethylpentane,n-hexane,n-hepatane, 1,3-difluorobenzene, 1,2-dichloroethane, hexafluorobenzene, cyclohexane and diphenyl ether, as new reference materials
for energy and temperature calibrations of differential thermal analysers (DTA) and differential scanning calorimeters (DSC)
in the temperature range 100–300 K, were investigated. The purities, triple point and transition temperatures, fusion and
transition enthalpies of these compounds were measured using a low-temperature DTA apparatus developed by the CTM of the CNRS
in Marseille. The results obtained were compared with those produced by adiabatic precision calorimetry. Our data are in good
agreement with literature values. Enthalpies of fusion and transition, triple point and transition temperatures are reproduced
within ±1% and ±0.1K, respectively.
during the period 1991–2. 相似文献
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Reliability and accuracy of measurements in food and agricultural materials are essential both for implementation of the legislation concerning public health and consumer protection and for the elimination of disputes arising from trade requirements and technical barriers. In such process the crucial step is represented by the programmes aimed at the quality assurance of analytical data produced by laboratories involved in food analysis. In this framework a major role is played by the proper use of reference materials. This report provides an overview on relevance, availability, use, certification procedures and perspective of reference materials in food analysis. Measurement harmonization procedures are also discussed. 相似文献
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Three Egyptian phosphate reference materials (S1, S2 and S3) were investigated using short-term activation analysis. The precision of the determination of Dy, Sc, Gd, Yb, Mg, V, F, Al, Mn, and Ca by this method ranged from 2 to 5% due to the homogeneity factor. Another 11 elements were determined by NAA using medium and long-lived nuclides. Most results were in good agreement with the recommended values. The values of Dy and Gd are reported. 相似文献
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This paper describes the COMAR database for certified reference materials (CRMs). The Web-based version of COMAR is freely
accessible via the Internet. COMAR was established to assist laboratories in finding the CRMs needed. The database is maintained
in a collaboration of the world’s major CRM producers. The planned changes in the database as agreed at the last COMAR council
meeting in Prague in May 2006 are indicated.
相似文献
Thomas SteigerEmail: |
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Wise SA Poster DL Kucklick JR Keller JM Vanderpol SS Sander LC Schantz MM 《Analytical and bioanalytical chemistry》2006,386(4):1153-1190
For the past 25 years the National Institute of Standards and Technology (NIST) has developed certified reference materials
(CRMs), known as standard reference materials (SRMs), for determination of organic contaminants in environmental matrices.
Assignment of certified concentrations has usually been based on combining results from two or more independent analytical
methods. The first-generation environmental-matrix SRMs were issued with certified concentrations for a limited number (5
to 10) of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). Improvements in the analytical certification
approach significantly expanded the number and classes of contaminants determined. Environmental-matrix SRMs currently available
include air and diesel particulate matter, coal tar, marine and river sediment, mussel tissue, fish oil and tissue, and human
serum, with concentrations typically assigned for 50 to 90 organic contaminants, for example PAHs, nitro-substituted PAHs,
PCBs, chlorinated pesticides, and polybrominated diphenyl ethers (PBDEs).
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
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To address the measurement and standard needs of the food and nutrition communities, the National Institute of Standards and Technology (NIST) has developed a suite of food-matrix Standard Reference Materials (SRMs) characterized for nutrient concentrations. These food-matrix SRMs include infant formula, baby food, and typical diet composites; meat homogenate, oyster, mussel, and fish tissues; baking chocolate; peanut butter; and spinach. Many of these materials were developed based on recommendations of the food industry to populate a nine-sectored triangle, developed by the Association of Analytical Communities (AOAC) International, in which foods are positioned based on their fat, protein, and carbohydrate contents. Value assignment of proximates, vitamins, and elements of nutritional interest in these food-matrix SRMs has been based primarily on the combination of results from measurements at NIST and from a group of collaborating laboratories involved in food measurements. Food-matrix SRMs are now available that are representative of all nine sectors of the AOAC International food-matrix triangle. Current activities are focused on the development of SRMs for dietary supplements including botanical and multivitamin/multielement materials.Presented at the CCQM Workshop on Comparability and Traceability in Food Analysis, 18–19 November 2003, BIPM, Sèvres, France. 相似文献