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1.
A. R. Bleise B. Smodiš D. Glavic-Cindro R. M. Parr 《Journal of Radioanalytical and Nuclear Chemistry》2001,248(1):205-209
The International Atomic Energy Agency (IAEA) maintains a database of biological and environmental reference materials of natural origin (human and animal tissues, foods, plants, soils, sediments, etc.) for trace elements, radionuclides, stable isotopes, organic contaminants and other related measurands. The purpose is to help analysts to select reference materials for quality assurance purposes that match as closely as possible (i.e., with respect to matrix type and concentrations of the measurands of interest) the real samples that are to be analyzed. Former versions of this database were prepared in co-operation with the United Nations Environment Programme (UNEP), and provided as hardcopies free of charge. The latest version was from 1995. More recently the database has been updated by the IAEA so that it now contains more than 22,500 values (mass fraction or concentration) for 660 different measurands and 1,705 reference materials developed by 56 producers from 22 countries. This paper gives an overview of the structure and content of the database and of the two ways it may be browsed. Emphasis is given to reference materials that are intended to verifying analysis for radioanalytical measurements. The database is soon accessible on-line, cost-free, via the internet. 相似文献
2.
3.
Reference materials for small-sample analysis 总被引:1,自引:0,他引:1
R. Zeisler 《Analytical and bioanalytical chemistry》1998,360(3-4):376-379
Many modern analytical techniques use small solid samples and lack proper reference materials for their calibration and quality
assurance. A remedy to this deficiency may be in the development of a new genre of highly homogeneous natural matrix materials,
their properties being studied with analytical techniques such as PIXE and μ-PIXE, solid sampling AAS, scanning electron microscopy
in combination with electron probe X-ray microanalysis, and INAA. Suitable natural materials may be obtained in form of single
cell biological materials, finely dispersed suspensions and precipitates such as air particulate matter or sediments, and
by appropriate particle size reduction of complex matrices. Initial studies have been carried out on single cell green algae
biomass and air particulate matter, as well as several processed materials. Narrow particle size distributions with particles
preferably below 10 μm diameter may assure the desired analytical homogeneity. The determination of sampling parameters for
individual measurands will ascertain the utility of a material for small-sample analysis.
Received: 16 June 1997 / Revised: 24 September 1997 / Accepted: 27 September 1997 相似文献
4.
The International Atomic Energy Agency maintains a database of internationally available certified reference materials (CRM) of natural matrices. This database is periodically updated, and presently documents nearly 25,000 measurands in 1700 materials. The organic constituents are classified in five major groups of analytes – aliphatic and aromatic hydrocarbons (A), chlorinated hydrocarbons (B), pesticides (C), organometallic compounds (D) and other organic constituents (nutrients, etc.) (E). The matrices include natural materials such as body fluids, food products, soils, and sediments, terrestrial (e.g. plants), and anthropogenic products (e.g. dust, fly ash). These five organic groups of analytes encompass more than 2000 measurands for 420 different analytes in 230 materials. Of these measurands, 1682 (68%) are certified, and 768 (32%) are provided as informational values. Within each major group of analytes, measurands reported as informational values accounted for: A (35%); B (35%); C (26%); D (10%), and E (22%). The high proportion of informational values (i.e. non-certified values) for A, B, and C, compares well with a similar but undesirable situation faced in the nineteen-seventies in the inorganic area when simultaneous multielement techniques became available. In the case of D and E, it appears that mostly targeted analytes are measured, leading to a cohesive certification profile. Although the IAEA database is not equally comprehensive for all groups of analytes cited above, it can still serve as an useful indicator of the status of organic constituents in RMs. 相似文献
5.
The International Atomic Energy Agency maintains a database of internationally available certified reference materials (CRM) of natural matrices. This database is periodically updated, and presently documents nearly 25,000 measurands in 1,700 materials. The organic constituents are classified in five major groups of analytes aliphatic and aromatic hydrocarbons (A), chlorinated hydrocarbons (B), pesticides (C), organometallic compounds (D) and other organic constituents (nutrients, etc.) (E). The matrices include natural materials such as body fluids, food products, soils, and sediments, terrestrial (e.g. plants), and anthropogenic products (e.g. dust, fly ash). These five organic groups of analytes encompass more than 2000 measurands for 420 different analytes in 230 materials. Of these measurands, 1,682 (68%) are certified, and 768 (32%) are provided as informational values. Within each major group of analytes, measurands reported as informational values accounted for: A (35%); B (35%); C (26%); D (10%), and E (22%). The high proportion of informational values (i.e. non-certified values) for A, B, and C, compares well with a similar but undesirable situation faced in the nineteen-seventies in the inorganic area when simultaneous multielement techniques became available. In the case of D and E, it appears that mostly targeted analytes are measured, leading to a cohesive certification profile. Although the IAEA database is not equally comprehensive for all groups of analytes cited above, it can still serve as an useful indicator of the status of organic constituents in RMs. 相似文献
6.
J. Kučera P. Mader D. Miholová J. Száková I. Stejskalová V. Štěpánek 《Analytical and bioanalytical chemistry》1998,360(3-4):439-442
A set of test materials of the green alga Chlorella vulgaris with different levels of naturally bound Cd and about the same levels of other 13 essential or trace elements (BIOMA 1–4)
was produced for proficiency testing of laboratories involved in elemental analysis of food. Criteria of the laboratories’
performance, such as the z-score and combination scores RSZ and SSZ were evaluated and discussed in terms of their suitability
for proficiency testing using a set of test materials with the same matrix. The use of the test materials as a set of internal
reference materials has also been suggested.
Received: 23 May 1997 / Revised: 1 August 1997 / Accepted: 11 August 1997 相似文献
7.
T. Catterick D. Craston B. King R. F. Walker K. S. Webb 《Accreditation and quality assurance》1999,4(1-2):3-13
The UK Valid Analytical Measurement Programme has pump-primed developments in chemical metrology, through a major project
on reference methodology and reference materials. This paper provides an overview of developments during 1994–1997 and covers
work on primary methods for trace inorganic and trace organic analysis, including the use of isotope dilution mass spectrometry;
studies of sample pre-treatment, including digestion, extraction, and separation aimed at improving this weak link in the
traceability chain; prioritisation, production and marketing of both pure substance and matrix reference materials; and international
collaboration concerned with interlaboratory comparisons and the development of concepts, terminology and systems to underpin
the international chemical measurement system. References are given to a number of papers covering specific parts of the programme.
Received: 5 August 1998 · Accepted: 12 September 1998 相似文献
8.
The National Institute of Standards and Technology (NIST, formerly the National Bureau of Standards or NBS) has produced
numerous Standard Reference Materials (SRM) for use in biological and environmental analytical chemistry. The value listed
on the “NIST Certificate of Analysis” is the present best estimate of the “true” concentration of that element and is not
expected to deviate from that concentration by more than the stated uncertainty. However, NIST does not certify the elemental
concentration of every constituent and the number of elements reported in the NIST programs tends to be limited.
Numerous analysts have published concentration data on these reference materials. Major journals in analytical chemistry,
books, proceedings and “technical reports” have been surveyed to collect these available literature values. A standard statistical
approach has been employed to evaluate the compiled data. Our methodology has been developed in a series of previous papers.
Some subjective criteria are first used to reject aberrant data. Following these eliminations, an initial arithmetic mean
and standard deviation (S.D.) are computed from remaining data for each element. All data now outside two S.D. from the initial
mean are dropped and a second mean and S.D. recalculated. These final means and associated S.D. are reported as “consensus
values” in our tables.
Received: 25 April 1997 / Revised: 24 July 1977 / Accepted: 25 July 1997 相似文献
9.
S. D. Rasberry 《Analytical and bioanalytical chemistry》1998,360(3-4):277-281
Good projections about the use of reference materials (RMs) in the world of tomorrow are especially important to RM producers.
They need to know what kinds of RMs will be required in the future, by whom, and for what purposes. They need to know what
batch sizes to prepare of different kinds and how to allocate limited resources to best effect. The following steps may provide
a useful view of the future of reference materials: (1) Review of trends, (2) Projection of challenges, (3) Analysis of driving
forces and construction of scenarios, (4) Thinking “outside the box,” and (5) Selecting strategies. This paper will illustrate
the use of these steps for the field of reference materials in order to provide a framework for the role of reference materials
in the world of tomorrow.
Received: 6 May 1997 / Revised: 22 July 1997 / Accepted: 24 July 1997 相似文献
10.
U. Örnemark L. Van Nevel P. D. P. Taylor P. Robouch P. De Bièvre A. Uldall M. Loikkanen M. M. Müller J.-C. Libeer H. Steensland K. Hellsing A. Squirrell L. A. Penberthy D. Schiel T. Tamberg T. Walczyk J. W. H. Lam 《Accreditation and quality assurance》1999,4(11):463-472
In the seventh round of the Institute for Reference Materials and Measurements' International Measurement Evaluation Programme,
277 clinical laboratories from 17 countries participated. The measurands consisted of inorganic components, present at minor
and trace level, in a human liquid serum. Results for calcium, chloride, copper, magnesium, sodium, selenium and zinc are
reported and are compared to reference values established mainly by isotope dilution mass spectrometry and neutron-activation
analysis. The overall conclusion is that routine measurements of total concentrations of the components by clinical laboratories
are of high quality. The fraction of significant errors is small (0.5%) and the self-declared uncertainty values are generally
fairly realistic. Results are further commented on with respect to the recent development in metrology in chemistry.
Received: 5 March 1999 / Accepted: 24 July 1999 相似文献
11.
V. Balaram 《Accreditation and quality assurance》2000,5(8):325-330
Under an international collaborative certification programme, two new Polish soil reference materials, PL-1 (loess) and BPGM-1
(sandy loam soil), were analysed for 34 trace elements including all the rare earth elements using the acid decomposition
method and inductively coupled plasma - mass spectrometry (ICP-MS). After the certification by the organisers, the analytical
data obtained at our institute were compared with the certified data. 'Z-score' values calculated for individual trace elements
helped in the assessment of the quality of the data. While the majority of the data obtained on ICP-MS was very precise and
accurate, some of the data especially for elements such as Zr, Hf and Nb suffered from incomplete dissolution of the sample
and spectroscopic interferences. For some trace elements, certified data are not available for comparison. These features
together with the usefulness of interlaboratory collaborative programmes and ICP-MS for the certification of soil reference
materials are discussed.
Received: 6 August 1999 / Accepted: 28 February 2000 相似文献
12.
Stephen A. Wise Michele M. Schantz Barbara J. Koster Rabia Demiralp Elizabeth A. Mackey Robert R. Greenberg Mechthild Burow Peter Ostapczuk Ted I. Lillestolen 《Fresenius' Journal of Analytical Chemistry》1993,345(2-4):270-277
Summary Fresh frozen homogenates of pilot whale blubber and liver tissue were prepared for use as control materials for the determination of organic and inorganic contaminants in marine mammal tissue analyses. The blubber material was analyzed to determine 30 polychlorinated biphenyl congeners and 16 chlorinated pesticides using gas chromatography with electron capture detection and gas chromatographymass spectrometry. A total of 39 trace elements and methylmercury were determined in the liver homogenate using instrumental neutron activation analysis, voltammetry, and cold vapor atomic absorption spectroscopy. The preparation and analysis of these two tissue materials are part of the development of marine mammal tissue reference materials. 相似文献
13.
This article discusses the requirements for reference materials (RMs) for measuring the size of nanoparticles (NPs). Such RMs can be used for instrument calibration, statistical quality control or interlaboratory comparisons. They can come in the form of suspensions, powders or matrix-embedded materials [i.e. NPs integrated in a natural matrix (e.g., food, soil, or sludge)].At present, uncertainty about the most suitable form of material, the most relevant measurands and the most useful metrological-traceability statement inhibits the production of NP RMs. In addition, the lack of validated methods and qualified laboratories to produce NP RMs present formidable challenges.Metal, inorganic and organic NPs are available, but most of them are intended to be laboratory chemicals. With the exception of latex materials, certified RMs are not available, although some metrology institutes have started to develop such materials for colloidal gold and silica particles. 相似文献
14.
The role of matrix reference materials in the process of demonstrating the degree of equivalence of measurement results obtained
from intercomparisons is outlined, reviewing exemplary selected experience gained at BAM regarding the determination of organic
contaminants in environmental matrices.
The specific characteristics of reference materials employed in the process of demonstrating equivalence between laboratories
in the course of proficiency testing as well as the development, comparison and validation of methods are elaborated. The
demand is for series of appropriately characterised samples which are fit for the purpose and it is seen from representative
examples that the utilisation of such tailor-made RM designed to tackle the specific need of an analytical problem dominates
over certified matrix reference materials in this context. Concluding, the role of certified matrix reference materials in
quality assurance is briefly looked at both from the user’s and providers’ points of view.
Received: 9 September 2002 Accepted: 16 December 2002
Presented at CERMM-3, Central European Reference Materials and Measurements Conference: The function of reference materials
in the measurement process, May 30–June 1, 2002, Rogaška Slatina, Slovenia
Correspondence to R. Becker 相似文献
15.
R. v. Hentig T. Goldbrunner F. v. Feilitzsch G. Angloher 《Fresenius' Journal of Analytical Chemistry》1998,360(6):664-668
For the determination of trace elements in organic liquids radiochemical neutron activation analysis has been combined with
counting methods geared to various decay modes of indicator radionuclides leading to a high sensitivity required for ultrapure
samples. The activation parameters such as irradiation time, sample mass and neutron flux have been enlarged to the maximum
possible in the available irradiation facility. Separation yields and adsorption losses have been studied in detail for a
set of elements in order to rule out losses during the separation process. The attainable limits of detection are 2 · 10–16g/g for U and Lu, in the 5 · 10–15g/g range for Th and Sm, in the 1 · 10–14g/g region for La, 5 · 10–13g/g for Rb, Cd and 2 · 10–12g/g for K and In. Although the analysis focused on traces of naturally occurring radioisotopes, results for Cr, Fe, W and
Zn are presented as well.
Received: 14 May 1997 / Revised: 28 August 1997 / Accepted: 9 September 1997 相似文献
16.
W. Schr?n A. Detcheva B. Dre?ler K. Danzer 《Fresenius' Journal of Analytical Chemistry》1998,361(2):106-109
Direct solid sampling graphite furnace AAS (SS-GF-AAS) provides an advantageous alternative to the conventional AAS which
requires wet digestion of the samples. This method is suitable for trace element determination in calcium fluoride and other
fluoride-containing samples. Matrix effects were studied by using calibration standards, certified reference materials with
different matrices and by means of three-dimensional calibration. 3D calibration is suitable for selection of calibration
samples for more reliable analyses. Cu, Pb, Cd, Zn, and Fe were determined by means of calibration with variation of sample
weight using certified reference materials and suitable fluoride-containing calibration samples.
Received: 25 July 1997 / Revised: 15 December 1997 / Accepted: 20 December 1997 相似文献
17.
W. Schrön A. Detcheva B. Dreßler K. Danzer 《Analytical and bioanalytical chemistry》1998,361(2):106-109
Direct solid sampling graphite furnace AAS (SS-GF-AAS) provides an advantageous alternative to the conventional AAS which
requires wet digestion of the samples. This method is suitable for trace element determination in calcium fluoride and other
fluoride-containing samples. Matrix effects were studied by using calibration standards, certified reference materials with
different matrices and by means of three-dimensional calibration. 3D calibration is suitable for selection of calibration
samples for more reliable analyses. Cu, Pb, Cd, Zn, and Fe were determined by means of calibration with variation of sample
weight using certified reference materials and suitable fluoride-containing calibration samples.
Received: 25 July 1997 / Revised: 15 December 1997 / Accepted: 20 December 1997 相似文献
18.
The stability of pH and certified amounts of nitrate, ammonia, total soluble nitrogen, total soluble organic carbon, magnesium,
sodium, potassium and phosphorus obtained by extraction from air-dried (40 °C) soil samples by 0.01 mol/L CaCl2 solution during storage at –18 °C, 4 °C, ambient temperature, 40 °C and 70 °C was investigated in one calcareous soil and
one acid sandy soil. Even at storage times of 45 and 90 days, extractable amounts changed. Extractable amounts of P, NH4-N, total soluble N and soluble organic C increased even at a storage temperature of 40 °C. The pH was lower for samples stored
at a temperature of 70 °C and also the Mg concentration became lower at elevated storage temperatures after 45 days in both
soils. It is suggested that reference materials certified for values using unbuffered extractants should be stored at a temperature
not higher than 4 °C.
Received: 13 May 1997 / Revised: 16 July 1997 / Accepted: 18 July 1997 相似文献
19.
Eiliv Steinnes Åke Rühling Harri Lippo Ahti Mäkinen 《Accreditation and quality assurance》1997,2(5):243-249
In order to ensure quality assurance in large-scale environmental contamination studies involving many different analytical
laboratories, the use of calibrated reference materials is essential. Prior to a survey of atmospheric metal deposition in
1995 comprising 20 countries and covering large parts of Europe, the lack of suitable reference materials of moss and organic-rich
soil was apparent. In order to improve the quality of analytical data to be produced in this international survey, candidate
analytical laboratories were invited to participate in an intercomparison exercise. Three moss and three soil humus reference
samples specifically prepared for this purpose were distributed anonymously among the laboratories, which were asked to report
data for ten priority elements (V, Cr, Fe, Ni, Cu, Zn, As, Cd, Hg, Pb) and as many additional elements as they determined
normally. In this paper the analytical data from the intercomparison are evaluated, and recommended values for the ten priority
elements and 17 additional elements (B, Na, Mg, Al, S, K, Ca, Mn, Co, Se, Rb, Sr, Sb, Cs, Ba, La, Th) in each of the six reference
samples are established. These samples should be useful for similar future studies including areas where the contamination
levels are very low.
Received: 17 October 1996 Accepted: 2 January 1997 相似文献
20.
Zeisler R Paul RL Oflaz Spatz R Yu LL Mann JL Kelly WR Lang BE Leigh SD Fagan J 《Analytical and bioanalytical chemistry》2011,399(1):509-517
A material containing single-wall carbon nanotubes (SWCNTs) with other carbon species, catalyst residues, and trace element
contaminants has been prepared by the National Institute of Standards and Technology for characterization and distribution
as Standard Reference Material SRM 2483 Carbon Nanotube Soot. Neutron activation analysis (NAA) and inductively coupled plasma
mass spectrometry (ICP–MS) were selected to characterize the elemental composition. Catalyst residues at percentage mass fraction
level were determined with independent NAA procedures and a number of trace elements, including selected rare earth elements,
were determined with NAA and ICP–MS procedures. The results of the investigated materials agreed well among the NAA and ICP–MS
procedures and good agreement of measured values with certified values was found in selected SRMs included in the analyses.
Based on this work mass fraction values for catalyst and trace elements were assigned to the candidate SRM. 相似文献