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51.
Herfried Kohl 《Accreditation and quality assurance》1998,3(10):422-425
This paper offers a concise overview of the recent draft of ISO 17025, which is expected to replace EN 45001 in 1999. Reference
is made to the general area of related ISO standards for management systems. The main changes compared with EN 45001 are discussed
for testing laboratories. 相似文献
52.
Many certified reference materials are needed to calibrate and control analytical measurement processes in integrated steel
works. It is beyond the scope and capacity of most national laboratories to supply all of these needs. Yet, the demand for
these materials is steadily increasing as more steel producers update their quality systems in preparation for ISO 9000 registration
and/or ISO Guide 25 laboratory accreditation assessments. This paper describes how the Bethlehem Steel Corporation updated
its reference materials program to meet its internal needs and offers a model for use by others in improving their programs.
Received: 22 April 1998 · Accepted: 12 May 1998 相似文献
53.
C. J. Powell 《Surface and interface analysis : SIA》2007,39(5):464-466
This article is a brief summary of the ISO Standard 20903. This standard provides information on methods for the measurement of peak intensities in Auger electron and X‐ray photoelectron spectra and on uncertainties of the derived peak areas. It also specifies the necessary information required in a report of analytical results based on such measurements. Published in 2007 by John Wiley & Sons, Ltd. 相似文献
54.
Public Health Laboratories (PHL) as part of Public Health Services are involved in law enforcement and ensuring food and water
quality. The laboratories had to go through an organizational and monetary change imposed by the growing and changing needs
of the state of Israel. The laboratories had to become more modern and to implement new and more sophisticated testing methods.
Another requirement was to perform a steadily increasing number of tests and to be more flexible towards customers’ demands.
Yet, the budget was not changed accordingly, as the Public Service to which the laboratories belong to do not respond to changing
needs. Management realization was that the accreditation process could be used as a tool to achieve organizational and cultural
change. Understanding and transformation were required throughout the organization, including management. Proficiency testing
is performed for all testing methods in all areas even for non-accredited tests such as clinical tests. Proficiency testing
was used as a tool for organizational culture change. It is a great index with game elements, that gives employees and managers
the possibility for comparison, fixing problems and corrective action. The demands of ISO 17025 made it necessary to change
peoples’ attitudes and views on both professional and communication levels. Laboratory quality consists now on the four main
principles, described in the 5M&E model which is typical to small organizations and which ensures a constantly improving system:
”Policy statement”, ”Machine”, ”Material”, ”Measurement”, ”Method”, ”Manpower”, and ”Environment” targeted to achieve ”Quality
upgrade”. Slowly we succeeded in providing better and more reliable services and have increased our income on what would hopefully
become our way to financial independence. We hope this process would provide the Ministry of Health with a better chance to
public health using the same financial sources.
Received: 25 October 2000 Accepted: 12 December 2000 相似文献
55.
56.
Koichi Machida Akira Kotani Yuzuru Hayashi Hideki Hakamata 《Journal of mass spectrometry : JMS》2022,57(8):e4877
ISO 11843 part 7 (ISO 11843-7) can provide a standard deviation (SD) of area measurements of a target peak through the stochastic behaviors of instrumental noises. The purpose of this study is to demonstrate that ISO 11843-7 can be applied to assess repeatability in an isocratic liquid chromatography–tandem mass spectrometry (LC–MS/MS) system without repetitive measurements. The relative standard deviation (RSD) of the peak area of ergosterol picolinyl ester, which was used as an example, on a multiple reaction monitoring (MRM) chromatogram was determined by ISO 11843-7. The RSD by ISO 11843-7 (N = 1) was within a 95% confidence band of the RSD by repetitive measurements (N = 6). Moreover, the effects of digital smoothing, such as moving average, were also examined on the repeatability assessment in LC–MS/MS by ISO 11843-7. From the results of the comparisons of the RSDs obtained by ISO 11843-7 and the repetitive measurements, it was shown that suitable RSDs of the peak area were obtained from the smoothed MRM chromatograms by the moving average for narrow data point windows (e.g., one-sixth of the peak width). In conclusion, the utility of repeatability assessment based on ISO 11843-7 has been expanded for the validation of an LC–MS/MS system. 相似文献
57.
Florentina Cañada-Cañada Anunciación Espinosa-Mansilla Arsenio Muñoz de la Peña Alicia Mancha de Llanos 《Analytica chimica acta》2009,648(1):113-2374
A liquid chromatographic method for the simultaneous analysis of marker pteridins and biopterin reduced forms, in urine samples is proposed. A Zorbax Eclipse XDB-C18 column was used for the chromatographic separation, using a 98/2 (v/v), citrate buffer (pH 5.5)-acetonitrile mobile phase, in isocratic mode. A post-column photoderivatization was carried out with an on-line photoreactor, located between a diode array detector (DAD) and a fast scanning fluorescence detector (FSFD). Neopterin (NEO), biopterin (BIO), pterin (PT) and dihydrobiopterin (BH2) were determined by measuring native fluorescence, using the photoreactor in OFF-mode, and tetrahydrobiopterin (BH4) was determined by measuring of the induced fluorescence of the generated photoproducts, using the photoreactor in ON-mode. In addition, Creatinine (CREA), as a reference of metabolites excrection in urine, was simultaneously determined using the DAD detector. Detection limits were 0.2, 13.0, 0.3, 0.3 and 3.5 ng mL−1, for NEO, BH2, BIO, PT and BH4, respectively, and 0.4 μg mL−1 for CREA. Ratio values for NEO/CREA, PT/CREA, BH4/CREA, BH2/CREA, NEO/BIO and BIOtotal/CREA, in urine samples, of healthy children and adults, phenylketonuric children and infected mononucleosis children, are reported. A comparative study, about the mean values obtained for each of the compounds, by the present procedure and by the classical iodine oxidation method (Fukushimás method), has been performed, in urine samples belonging to healthy volunteers. The values obtained were BH4/CREA: 0.41, BH2/CREA: 0.31 and BIOtotal/CREA: 0.73, by the proposed method, and BH4/CREA: 0.35, BH2/CREA: 0.20 and BIOtotal/CREA: 0.48, by iodine oxidation method. 相似文献
58.
对《ISO 4934-1980(E)钢和铸铁-硫含量的测定-重量法》中(1)不溶于稀硝酸的试样的溶解;(2)铬干扰的消除;(3)坩埚的恒重;(4)BaSO_4真换算成硫(S)的换算系数提出了修改意见。 相似文献
59.
Steven?WestwoodEmail author Bernard?King Bruce?Noble 《Accreditation and quality assurance》2003,8(9):424-427
The National Analytical Reference Laboratory of the Australian Government Analytical Laboratories was initially accredited to ILAC Guide G 12:2000 in January 2000 and is currently accredited to ISO Guide 34 (2000) for the production of a range of pure organic substance reference materials. This paper discusses the practical challenges and rewards of developing and implementing a quality system for reference material production and discusses some of the barriers, and potential solutions, to more general implementation of third-party accreditation. 相似文献
60.
《Analytica chimica acta》2004,501(2):193-203
According to the committee decision of 12 August 2002 (2002/657/EC) the capability of detection, CCβ, must be set in all analytical methods not only at concentration levels close to zero but also at the maximum permitted limit (PL). In this work we describe a methodology which evaluates the capability of detection of a fluorescence technique with soft calibration models (bilinear and trilinear PLS) to determine tetracyclines (group B1 substances from annex 1 of Directive 96/23/EC). Its estimation is based on the generalisation of the procedure described in International Union of Pure and Applied Chemistry and in the ISO standard 11843 for univariate signals which evaluates the probabilities of false positive (α) and false negative (β). The capability of detection, CCβ, estimated from the second-order signal and the trilinear PLS model is 9.93 μg l−1 of tetracycline, 17.75 μg l−1 of oxytetracycline and 26.31 μg l−1 of chlortetracycline, setting α and β at 0.05. The capability of detection, CCβ, determined around the PL (100 μg kg−1 in milk and muscle) with the second-order signal is 109.4 μg l−1 of tetracycline, 117.0 μg l−1 of oxytetracycline and 124.9 μg l−1 of chlortetracycline, setting α and β at 0.05. The results were compared with those obtained with zero and first-order signals. The effect of the interferences on the capability of detection was also analysed as well as the number of standards used to build the models and their calibration range.When a tetracycline is quantified in presence of uncalibrated ones by means of the trilinear PLS model the errors oscillate between 14.70% for TC and 9.57% for OTC. 相似文献