Uncertainty in photometric analysis: a case study

A procedure for estimation of measurement uncertainty of photometric analysis based on the ISO GUM method is presented. Two variations of the procedure—for the calibration graph and the standard addition method, respectively—are discussed. The variations are based on mathematical models involving 64 and 80 input quantities, respectively. The uncertainty of the result strongly depends on changes in experimental details. These dependencies are explored for a practical example of determination of the iron content of aluminum. The importance of taking uncertainty from sample preparation into account in uncertainty estimation is stressed. The number of effective degrees of freedom is calculated and discussed. The examples are available as GUM Workbench files in the Electronic Supplementary Material.Electronic Supplementary Material  Supplementary material is available for this article at .

Summary of ISO/TC 201 standard: XVIII,ISO 19318:2004—surface chemical analysis—X‐ray photoelectron spectroscopy—Reporting of methods used for charge control and charge correction

International Standard ISO 19318 specifies the minimum amount of information describing the methods of charge control and charge correction in measurements of core‐level binding energies for insulating specimens by x‐ray photoelectron spectroscopy, which is to be reported with the analytical results. Information is also provided on methods that have been found useful for charge control and charge correction in the measurement of binding energies. Copyright © 2005 John Wiley & Sons, Ltd.     

The present situation of Japanese certified reference materials registered in the COMAR database

 In the field of reference materials, COMAR (Code d'Indexation des Matériaux de Référence) is now internationally known as a reliable directory. In order to improve the quality of COMAR, a document which covers general requirements for the registration of reference material has recently been adopted by the Japanese coding centre, NITE. This paper describes the general requirements for reference materials and the current status of the COMAR database coded by the National Institute of Technology and Evaluation (NITE), Japan. The concept of the requirements is fundamentally based on the ISO Guides 30, 31, 33, 34 and 35. Certifications of reference materials are divided into the following three categories in the newly adopted document. 1. Certifications based on the results of interlaboratory comparisons 2. Certifications in accordance with the Measurement Law 3. Certifications in accordance with the measurement results of national institutions An example of an uncertainty evaluation is also presented in the paper. Received: 14 October 1996 Accepted: 3 December 1996     

Management review checklist for ISO/IEC 17025 and ISO 15189 quality-management systems

Management reviews are key processes in many quality-management systems, including laboratory-management systems, in accordance with ISO/IEC 17025 and ISO 15189. These reviews are fine opportunities to understand and manage all the inputs and outputs of a quality-management system. Laboratories often meet some difficulties fully exploiting the management-review process because either they do not realize the importance of this process or they do not have the experience to run this process in a way producing the intended results. This work presents a management review checklist which helps laboratories carry out an effective management review going through all the important aspects of the quality-management system.     

符合ISO/IEC指南25-1990的实验室质量体系向ISO/IEC 17025-1999标准过渡的文件修改

按照ISO／IEC指南25－1990建立起较完善的质量体系的实验室,可通过对质量体系文件进行适当增补或少量删减,以实现向ISO／IEC 17025－1999标准的过渡。对质量手册,按照ISO／IEC指南25－1990的13个要素逐个讨论了具体的增删内容;对程序文件,则按ISO／IEC 17025－1999要求逐个列出了应有的程序。     

Four vignettes on interactions with Martin Seah: The impact of his work

Four brief vignettes briefly describe ways that Dr. Martin Seah influenced my career and those of many others. These brief stories highlight aspects of his (i) career-long contributions to the quantification and accuracy of surface analysis, (ii) ability to identify and willingness to fill information gaps and needs, (iii) significant efforts to communicate the nature of the challenges and what was known about best practices in an engaging and often humorous manner, and (iv) many delightful professional and social interactions that also contributed to community impact.     

ISO/REMCO近期活动

介绍ISO/REMCO 2007年已开展的和2008年将要开展的工作.重点介绍ISO/REMCO与标准物质相关的文件制定等一系列工作.     

Isolation and analysis of polycyclic aromatic hydrocarbons from natural water using accelerated solvent extraction followed by gas chromatography-mass spectrometry

An innovative analytical procedure for the analysis of polycyclic aromatic hydrocarbons (PAHs) from large-volume water samples is presented. It involves sample preparation, sampling and the elution process in an automated continuous procedure involving the ASE technique. Prior to sampling, a XAD-2 resin column is prepared on the basis of a commercial accelerated solvent extraction (ASE) cartridge so that the resin bed is permanently fixed. Then, the XAD column inside the ASE cartridge is cleaned and conditioned. The sampling procedure involves conventional filtration with subsequent isolation of dissolved PAHs on an XAD-2 resin contained in the ASE cartridge. After sampling, the XAD-2 resin content inside the cartridge is eluted by ASE without any further sample preparation and subsequently reused. In order to validate the procedure, the PAHs were isolated from water samples from the Lake Maggiore (North of Italy) using both XAD-2 resin adsorption and hexane liquid-liquid extraction according to the International Standard Methodology ISO 17993. The mean percentages of deviation between concentrations obtained by both methodologies range from 6% for benzo(a)pyrene to 15% for fluoranthene and benzo(b,k)fluoranthene. Compared to the traditional techniques, this procedure offers numerous practical advantages: easy to perform, fast, savings in solvent volume and in time, all steps are fully automated thus avoiding any XAD-2 resin manipulation during and between steps and moreover, low detection limits were provided (0.001 ng l⁻¹ for chrysene, benzo(b,k)fluoranthene, benzo(a)pyrene, dibenz(a,h)anthracene, benzo(g,h,i)perylene and indeno(1,2,3-cd)pyrene, and 0.01 ng l⁻¹ for acenaphthylene and fluoranthene).This procedure was developed in the frame of a project aimed at evaluating the diffuse input of organic contaminants in the Lake Maggiore.     

Biodegradation of poly(lactic acid) powders proposed as the reference test materials for the international standard of biodegradation evaluation methods

The methods for producing reference test materials for biodegradation evaluation tests have been studied. Mechanical crushing at low temperature of polymer pellets using dry ice was selected for the method of producing polymer powder of poly(lactic acid) (PLA). The powders were fractionated using 60 mesh (250 μm) and 120 mesh (125 μm) sieves. The size distributions were then measured. The average diameter of the PLA particles obtained by this method was 214.2 μm. The biodegradation speeds of these PLA polymer powders were evaluated by two methods based on the international standard and one in vitro method based on the enzymatic degradation. First, the degree of biodegradation for this PLA powder was 91% for 35 days in a controlled compost determined by a method based on ISO 14855-1 (JIS K6953) at 58 °C managed by the Mitsui Chemical Analysis and Consulting Service, Inc. (Japan). Second, these polymer powders were measured for biodegradation by the Microbial Oxidative Degradation Analyzer (MODA) in a controlled compost at 58 °C and 70 °C based on ISO/DIS 14855-2 under many conditions. The degree of biodegradation for this PLA powder was approximately 80% for 50 days. In addition, the polymer powders were biodegraded by Proteinase K which is a PLA degradation enzyme. This polymer powder was suitable as a reference material for the evaluation methods of biodegradation.     

水中氟化物国际标准检验方法的验证及其比较

介绍水中氟化物国际标准检验方法的验证结果,其中包括了干扰实验、标准曲线、准确度、精密度、检出限等.并将本方法测定结果与国标同类方法进行了比较.结果表明,该方法抗干扰性好,测量精度高,其标准曲线范围宽,点数设计合理,优于国标中的同类方法.应加以采纳和推广.