scholarly journals Die invloed van verpoeiering op die kwikinhoud van verskeie gesertifiseerde verwysingsmateriale

2015 ◽  
Vol 34 (1) ◽  
Author(s):  
Frederick Roelofse ◽  
Kwenidyn Mulder
Keyword(s):  
Reference Materials ◽  
Significant Role ◽  
Milling Time ◽  
Certified Reference Materials ◽  
Analytical Techniques ◽  
Igneous Rocks ◽  
Geological Materials

The majority of analytical techniques, aimed at establishing the mercury contents of geological materials, require comminution of samples prior to analysis. This typically involves a process of crushing, followed by milling. It is known that heat is generated during milling in conventional milling apparatuses; therefore mercury losses may be expected due to the element’s volatility. To investigate mercury losses during milling, we analysed the mercury contents of nine certified reference materials of igneous rocks before milling and after respectively 3 and 10 minutes of milling, using a direct mercury analyser. The results of the experiments suggest that: (1) mercury losses are insignificant after 3 minutes of milling, (2) mercury losses become significant when samples undergo excessive milling, (3) mercury losses do not appear to be mineralogically controlled and (4) for samples with low mercury contents, contamination during milling plays a much more significant role in the analysed mercury contents than milling time.

APPLICATION OF AAS AND NAA FOR DETERMINATION OF TIN IN SRMs, AND IN ANIMAL AND HUMAN ORGANS

1992 ◽  
Vol 02 (04) ◽  
pp. 489-491 ◽  
Author(s):  
MOMOKO CHIBA ◽  
VENKATESH G. IYENGAR
Keyword(s):  
Neutron Activation Analysis ◽  
Activation Analysis ◽  
Reference Materials ◽  
Certified Reference Materials ◽  
Analytical Techniques ◽  
Absorption Spectrometry ◽  
Dry Weight ◽  
Mixed Diet ◽  
Human Organs

Tin (Sn) is one of the causative elements of the environmental pollution. As no certified reference materials for Sn are presently available, existing reference materials were analyzed for Sn by two independent analytical techniques; atomic absorption spectrometry (AAS) and neutron activation analysis (NAA). The results obtained by both methods were in agreement except for mixed diet which contains Sn in the range of 50 μ g/g. Further, tin concentrations in human and animal organs have been examined by AAS. Among organs tested tin concentrations in testes were the highest, 2.08±0.62 μ g/g dry weight (mean ±SD, n=12) in humans, and 1.45±0.55 μ g/g (n=8) in mice.

scholarly journals Two New Reference Materials Based on Tobacco Leaves: Certification for over a Dozen of Toxic and Essential Elements

2012 ◽  
Vol 2012 ◽  
pp. 1-16 ◽  
Author(s):  
Zbigniew Samczyński ◽  
Rajmund S. Dybczyński ◽  
Halina Polkowska-Motrenko ◽  
Ewelina Chajduk ◽  
Marta Pyszynska ◽  
...  
Keyword(s):  
Reference Materials ◽  
Interlaboratory Comparison ◽  
Statistical Evaluation ◽  
Certified Reference Materials ◽  
Analytical Techniques ◽  
Essential Elements ◽  
Tobacco Leaves ◽  
Certified Values

The preparation, certification, and characterization of two new biological certified reference materials for inorganic trace analysis have been presented. They are based on two different varieties of tobacco leaves, namely, Oriental Basma Tobacco Leaves (INCT-OBTL-5), grown in Greece, and Polish Virginia Tobacco Leaves (INCT-PVTL-6), grown in Poland. Certification of the materials was based on the statistical evaluation of results obtained in a worldwide interlaboratory comparison, in which 87 laboratories from 18 countries participated, providing 2568 laboratory averages on nearly 80 elements. It was possible to establish the certified values of concentration for many elements in the new materials, that is, 37 in INCT-OBTL-5 and 36 in INCT-PVTL-6, including several toxic ones like As, Cd, Hg, Pb, and so forth. The share and the role of instrumental analytical techniques used in the process of certification of the new CRMs are discussed.

Microparticle production as reference materials for particle analysis methods in safeguards

MRS Advances ◽  
2018 ◽  
Vol 3 (19) ◽  
pp. 1005-1012
Author(s):  
Stefan Neumeier ◽  
Ronald Middendorp ◽  
Alexander Knott ◽  
Martin Dürr ◽  
Martina Klinkenberg ◽  
...  
Keyword(s):  
Size Distribution ◽  
Reference Materials ◽  
Uranium Oxide ◽  
Particle Production ◽  
Certified Reference Materials ◽  
Analytical Techniques ◽  
Particle Analysis ◽  
Nuclear Facilities ◽  
Energy Agency ◽  
Analysis Methods

The application of safeguards measures by the International Atomic Energy Agency (IAEA) involves analytical measurements of samples taken during inspections of nuclear facilities. Thus constant development and advancement of analytical techniques is required. For quality control purposes, the IAEA has implemented a dedicated project to enhance its analytical capabilities by producing tailor-made reference materials for the analysis of uranium isotope signatures in (single) particles.To this end, a particle production set-up was developed and implemented at Forschungszentrum Juelich capable to produce uranium oxide microparticles which are intended to be used as (certified) reference materials for particle analysis methods. A step towards the certification process is the evaluation of consistency of the size distribution and homogeneity. A monodisperse particle size distribution as well as the single phase triuranium octoxide structure was confirmed using SEM, µ-XRD and µ-Raman spectroscopy, respectively. Analysis performed on single uranium oxide microparticles confirmed consistency of the uranium isotopic ratios in comparison to the initial precursor solutions. To improve the homogeneity and particle handling, the particles are transferred into suspensions, for which the stability was investigated with respect to dissolution.

scholarly journals Preparation of Three New Certified Reference Materials for Food and Environmental Analysis and Certification Using Laboratory Intercomparison as well as Primary Reference Measurement Procedures

2021 ◽  
Author(s):  
Halina Polkowska-Motrenko ◽  
Zbigniew Samczyński ◽  
Rajmund S. Dybczyński ◽  
Ewelina Chajduk ◽  
Bożena Danko ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Reference Materials ◽  
Trace Analysis ◽  
Inductively Coupled Plasma ◽  
Certified Reference Materials ◽  
Isotope Dilution Mass Spectrometry ◽  
Analytical Techniques ◽  
Reference Measurement ◽  
Certification Procedure ◽  
Primary Reference

AbstractThree new reference materials: MODAS-3 Herring Tissue (M-3 HerTis), MODAS-4 Cormorant Tissue (M-4 CormTis), and MODAS-5 Cod Tissue (M-5 CodTis) were prepared and certified on the basis of results of a worldwide intercomparison exercise. Independently of our proven method of establishing the certified and information values, the content of several essential and toxic elements was additionally determined by the use of ratio primary reference measurement procedures (definitive methods) based on radiochemical neutron activation analysis (RNAA) in the case of As, Cd, Co, Cr, Fe, Mo, Se, and U and isotope dilution mass spectrometry (IDMS) in the case of Hg, respectively. Good agreement of the established certified values and the results obtained by ratio primary reference measurement procedures confirmed the validity of the certification procedure. The total number of elements which could be certified amounted to 30, 21, 18 in M-3 HerTis, M-4 CormTis, and M-5 CodTis, respectively. The relative frequency of use of individual analytical techniques in this intercomparison campaign was calculated and discussed. Inductively coupled plasma mass spectrometry (ICP-MS) is now a dominant technique, followed by atomic absorption spectroscopy (AAS), NAA, and emission spectroscopy (ES). The decreasing share of NAA as compared to several earlier intercomparison exercises should be noticed. NAA is the only method in the array of highly sensitive methods of inorganic trace analysis, which is essentially free from blank. The lack of this method in the foreseeable future may be an obstacle in the prospective certification campaigns and may endanger the implementation of quality assurance in trace analysis.

scholarly journals Geological materials testing and uncertainty calculations: a simple GUM-based algorithm

2013 ◽  
Vol 47 (4) ◽  
pp. 2081
Author(s):  
D. Xirouchakis ◽  
A. Bouzinos
Keyword(s):  
Standard Deviation ◽  
Reference Materials ◽  
Proficiency Test ◽  
Certified Reference Materials ◽  
Physical And Mechanical Properties ◽  
Standard Uncertainty ◽  
Materials Testing ◽  
Geological Materials ◽  
Repeatability Standard Deviation ◽  
Proficiency Test Data

We have applied a simple GUM-based procedure to estimate the uncertainties of physical and mechanical properties in geological materials. First, we define the quantity to measure and decide whether we want to work with units or relative quantities. Subsequently, we calculate the repeatability standard deviation (sr) and the standard uncertainty. If we have proficiency test data or use certified reference materials, we use them to estimate the laboratory bias, the reproducibility standard deviation (sR) and the reproducibility standard uncertainty. We also make sure that we know or have estimated the standard uncertainty of the instruments that we use in the measurements. The latter is typically taken from the instrument calibration or precision statement. We estimate the standard uncertainty of the reference materials and the standard uncertainty of the laboratory bias. The final two steps include the calculation of (1) the laboratory standard uncertainty uncorrected for bias and corrected for bias, and (2) the laboratory expanded uncertainty at the 95% confidence limit.

Layered and ion implantation specimens as possible reference materials for the electron-probe microanalysis

1992 ◽  
Vol 50 (2) ◽  
pp. 1652-1653
Author(s):  
G. Remond ◽  
R.H. Packwood ◽  
C. Gilles ◽  
S. Chryssoulis
Keyword(s):  
Ion Implantation ◽  
Reference Materials ◽  
Analytical Techniques ◽  
Thin Film Deposition ◽  
Film Deposition ◽  
X Ray ◽  
Spatially Resolved ◽  
Analytical Expressions ◽  
Original Approach ◽  
Depth Concentration

Merits and limitations of layered and ion implanted specimens as possible reference materials to calibrate spatially resolved analytical techniques are discussed and illustrated for the case of gold analysis in minerals by means of x-ray spectrometry with the EPMA. To overcome the random heterogeneities of minerals, thin film deposition and ion implantation may offer an original approach to the manufacture of controlled concentration/ distribution reference materials for quantification of trace elements with the same matrix as the unknown.In order to evaluate the accuracy of data obtained by EPMA we have compared measured and calculated x-ray intensities for homogeneous and heterogeneous specimens. Au Lα and Au Mα x-ray intensities were recorded at various electron beam energies, and hence at various sampling depths, for gold coated and gold implanted specimens. X-ray intensity calculations are based on the use of analytical expressions for both the depth ionization Φ (ρz) and the depth concentration C (ρz) distributions respectively.

Development of reference materials with the composition of propyl and isopropyl alcohol solutions

2020 ◽  
pp. 66-72
Author(s):  
Irina A. Piterskikh ◽  
Svetlana V. Vikhrova ◽  
Nina G. Kovaleva ◽  
Tatyana O. Barynskaya
Keyword(s):  
Reference Materials ◽  
Measurement Errors ◽  
Isopropyl Alcohol ◽  
Certified Reference Materials ◽  
Toxic Substances ◽  
Biological Objects ◽  
Margin Of Error ◽  
Measurement Results ◽  
And Control ◽  
Characteristic Mass

Certified reference materials (CRM) composed of propyl (11383-2019) and isopropyl (11384-2019) alcohols solutions were created for validation of measurement procedures and control of measurement errors of measurement results of mass concentrations of toxic substances (alcohol) in biological objects (urine, blood) and water. Two ways of establishing the value of the certified characteristic – mass consentration of propanol-1 or propanol-2 have been studied. The results obtained by the preparation procedure and comparison with the standard are the same within the margin of error.

Sign in / Sign up

Export Citation Format

Share Document