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Abstract  

Trace impurity elements in high purity copper metal (4 mine class) put on the market were analyzed by Instrumental Neutron Activation Analysis (INAA) and the results compared with those from Graphite Furnace Atomic Absorption Spectrophotometry (GFAAS) and Inductively Coupled Plasma Atomic Emission Spectrophotometry (ICP-AES). The sample irradiation was done at the irradiation facilities (thermal neutron flux, 5·1012 n·cm−2·s−1) of the TRIGA Mark-III research reactor in the Korea Atomic Energy Research Institute. Four unalloyed copper standards (NIST SRM # 393, 394, 395 and 398) were used to identify the accuracy and precision of the analytical procedure. The homogeneity of samples was assessed by means of the elements such as Ag, As, Co, Sb, Se and Zn. The analytical results of INAA, GFAAS and ICP-AES were in good agreement within expected uncertainties each other and showed the possibility of using them for the analytical quality control.

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Abstract  

The IAEA's Marine Environment Laboratory has been assisting laboratories in Analytical Quality Control Services (AQCS) for the analysis of radionuclides in the marine environment since the early seventies. AQCS through world-wide and regional intercomparison exercises and the provision of reference methods and reference materials (RM) have been recognized as an important component of quality assurance/quality control. A total of 43 intercomparison exercises were organized and 37 RM were produced for marine radioactivity studies. All important marine matrices were covered, e.g., seawater, marine sediments of different chemical compositions, fish, shellfish and seaplants. RM were prepared from samples collected at contaminated sites (e.g., the Irish Sea, the Baltic Sea, the Arabian Sea, Mururoa and Bikini Atolls, etc.) as well as from sites affected only by global fallout (e.g., the Pacific Ocean). Available RM are listed in the IAEA biennial catalogue and can be purchased at a minimal price. An overview of prepared RM for radionuclides in marine matrices is presented and discussed in more detail.

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Abstract  

At ITN, PM10 and PM2.5 aerosols were collected on Nuclepore® polycarbonate filters of 47 mm diameter, using Gent samplers at 15–17 l/min air flux. Filters were analyzed by INAA and PIXE. The availability of certified filters was very scarce, viz.: (1) fly ash embedded in a methyl cellulose 47 mm foil 10 µm thick, BCR CRM128, (2) particle-size reduced air particulate matter (APM) to simulate PM2.5 aerosol matter deposited on a 47 mm polycarbonate filter membrane, NIST SRM 2783. The high price and scarcity of APM standards did not permit their frequent use for analytical quality control. At ITN, to control the filter results' accuracy, the chemical elements potassium, iron and zinc, determined by both techniques, were systematically compared. After a few improvements introduced in INAA, this technique was now considered at ITN as the reference technique in air particulate measurements. Comparison of INAA to PIXE was discussed. Compared to previously reported situation it was concluded that the results were in better agreement for iron and zinc, and potassium values were still biased to the same extent as before.

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Abstract  

Twenty laboratories from 17 countries around the world participated in two analytical quality control exercises, coded NAT-5 and NAT-6, on determining trace and minor elements in plant bioindicator samples. 1398 laboratory mean values for 51 elements were submitted for two lichen and two moss materials. The submitted measurement results were evaluated as interlaboratory comparison (IC) exercises and as proficiency tests (PT) following standard procedures developed by the International Atomic Energy Agency (IAEA). The evaluations confirmed good performance of the participating laboratories for many elements. Furthermore, the laboratories performance based on IC criteria improved from the first exercise to the second one. Subsequent NAT-5 evaluation revealed systematic differences between the analytical values obtained non-destructively or after the total sample dissolution and the measurements following nitric acid sample dissolution (without the use of hydrofluoric acid) for some elements. The most critical elements for this kind of discrepancies appeared to be Al, Ca, Cr, Fe, Na, Ni, and Pb. After changing analytical methodologies in the concerned laboratories, more consistent values for those elements were obtained in NAT-6.

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Abstract  

The aim of the research is to find out better medicinal stuff for thyroid cancer patients who are required to have a low level iodine diet. Iodine contents in 12 kinds of oriental herbal medicinal prescriptions, which are frequently used for thyroid cancer patients, are determined using instrumental neutron activation analysis. The biological certified reference material was used for analytical quality control. The relative errors and standard deviations for the iodine analysis were less than 2.88 and 18.5%, respectively. The level of iodine contents for four medicinal samples detected was in the range of about 3–210 mg/kg, the concentrations of eight samples were estimated from the detection limit under the given analytical conditions. In addition, the informative concentrations of 17 essential elements with special functions such as Al, As, Ba, Br, Ca, Cl, Cr, Fe, K, Mg, Mn, Na, Rb, Sr, Ti, V, and Zn in the samples were also determined together with their detection limits for data inter-comparison. The relative errors and standard deviations for these elements were in the range of 0.1–18.0%, and 2–20%, respectively.

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Abstract  

Due to changes of the dietary pattern and life style, cardiovascular diseases like coronary heart disease (CHD) have been increasing in Korea. In this study, the levels of the serum minerals such as Na, Cl, K, Ca, Fe, Zn and Se for 75 patients with CHD and 25 normal persons, who were older than the age of 40, were investigated by instrumental neutron activation analysis. For analytical quality control, the reference materials. INSPQ and Seronorm, were analyzed simultaneously. The relative errors of the analytical values for the reference materials were within 10% of the certified values. The average concentrations of Na, Cl, K, Ca, Fe, Zn and Se in the serum of the male patients were 2,850±260 mg/1, 3,400±310 mg/l, 160±30 mg/l, 80.9±11.7 mg/l, 1.57±0.73 mg/l, 0.094±0.019 mg/l and 0.795±0.163 mg/l, respectively. The concentrations of Na, Cl, K, Ca, Fe, Zn and Se in the serum of the female patients were 2,890±240 mg/l, 3,430±350 mg/l, 169±27 mg/l, 81.8±13.0 mg/l, 1.26±0.44 mg/l, 0.099±0.015 mg/l and 0.769±0.105 mg/l, respectively. In a comparison between the patients and the normal group for both genders, while the levels of the elemental concentrations such as Na, Cl, K, Ca, Fe and Se were similar, the Zn concentration level of the CHD patients was significantly lower than that of the normal ones. The present study showed that the Zn concentration in the serum could be associated with CHD in Korean adults.

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. 2015 , 2015 , 1 – 5 . 10.1155/2015/592763 23. SANTE/11945/2015 . Guidance document on analytical quality control and method validation procedures

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-953-51-0681-4, Chapter 3 ; Publisher InTech , 2012 . 19. Main changes introduced in Document Nº SANTE/12682/2019 with respect to the previous version (Document Nº SANTE/11813/2017) . Guidance document on analytical quality control and validation procedures for

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