Determination of the content of impurity elements in a sample of high purity India by the method of radiochemical neutron activation analysis

The present article is devoted to the development of a method for neutron activation analysis of a microimpurity composition of high-purity indium with the radiochemical separation of indium radionuclides from radionuclides of the determined elements by extraction chromatography in the system tributyl phosphate (TBP) - solutions of hydrobromic acid (HBr). Neutron activation analysis (NAA) has a special place among the physical methods for determining the trace composition of high-purity substances. Low detection limits, the possibility of simultaneous determination of a large number of impurity elements from one sample, no correction for the control experiment, the possibility of using inactive carriers in separating traces of radionuclides of impurity elements from matrix elements ensured the widespread use of NAA in the analysis of highly pure substances. The developed technique allows separating matrix radionuclides from radionuclides of impurity elements with high efficiency and determination of 28 impurity elements in high-purity indium with detection limits of 0.7 ppm to 0.05 ppb.

Radiochemical neutron activation analysis for the determination of selenium in Mentha spicata L. samples collected from Djelfa, Algeria region

Selenium (Se) has been a focus of attention as an important micronutrient with its impact on human health, with there being consequences either due to excess or deficiency in intake. Radiochemical neutron activation analysis (RNAA) is well established method for determination of a number of elements at trace level concentrations with high sensitivities. In this work, we used the RNAA method for determination of selenium content in Mentha spicata L. The result of this study was compared with those samples from India and Serbia. The result obtained show that, Se concentration obtained in M. spicata L., is close to the minimal FAO recommendation.

Application of MnO2Resin and Dowex 1X8 manganese dioxide impregnated resin for the separation of chromium from biological samples

MnO2Resin and Dowex 1X8 manganese dioxide impregnated resin was used for chromium separation from biological samples. We examined sorption of chromium from acid solutions: hydrochloric, nitric and sulphuric in concentration range from 0.01 to 2 mol/dm3. The sorption process was evaluated by batch and column experiments. We also examined sorption of other elements in the developed systems, to check the selectivity of the process. Determination of chromium by radiochemical neutron activation analysis after separation with MnO2Resin was described.

Ratio primary reference measurement procedure (RPRMP) for the certification of chromium content in biological reference materials

Primary reference measurement procedure for Cr determination in biological samples by radiochemical neutron activation analysis (RNAA) has been elaborated. The procedure is based on quantitative and selective separation of chromium from neutron irradiated sample by column chromatography using MnO2-Resin and determination of 51Cr by γ-ray spectrometry. Quality components have been incorporated into the RNAA method which makes it possible to meet the requirements of the definition of ratio primary reference measurement procedure. The usefulness of the elaborated procedure to assign the certified values for Cr in new certified reference material (CRMs) based on animal tissues is demonstrated. The tentative certified values for Cr have been proposed for: MODAS M-4 Cormorant Tissue and M-5 Cod Tissue CRMs.

Determination of selenium in roasted beans coffee samples consumed in Algeria by radiochemical neutron activation analysis method

The essential trace element selenium is a focus of attention due to its effects on human health, there being consequences of both its deficiency and excess. Due to the ultra-trace content of selenium, the neutron activation analysis method (NAA) is difficult to apply. We therefore made use of the radiochemical neutron activation analysis (RNAA) to determine Se at low level concentrations in several consumed food items in Algeria. A radiochemical procedure based on liquid–liquid separation was established in our laboratory. In this research we focused on the determination of selenium in two species of coffee: Arabica and Robusta. The accuracy of the method was assessed by analyzing the certified reference material NIST-SRM 1573a (tomato leaves). The results obtained show a selenium variation from 0.025 to 0.052 μg/g in coffee beans and an average yield of the separation of about 85%. The results of this study were compared with those obtained with samples from Brazilian, Caribbean, Indian and Kenyan coffee beans.