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.

Looking for Ephesian workshops: an integrated petrographic, geochemical, and chrono-typological approach to Late Hellenistic Ephesos lamps

In this pilot study, Late Hellenistic mold-made lamps from Ephesos are investigated by combining chrono-morphological and stylistic features with thin-section petrography and neutron activation analysis. Coeval wares of Ephesian production and clay samples collected around the site as well as published data from the Bonn database are considered local reference material. The results point to a network of local/regional workshops sharing facilities and/or a labor force dedicated to distinct tasks. The whole evidence is consistent with the very beginning of a nucleated workshop industry able to optimize the productivity of mold-made wares and fill the demand of an increased regional and supra-regional market. The typological and compositional variability of the latest phases could suggest a gradual transfer of potting activities towards areas providing better-suited clay sources.

Comparison of Chemical Element Contents in Thyroid Goiter, Adenoma, and Thyroiditis investigated using Neutron Activation Analysis

Thyroid benign nodules (TBNs) are the most common lesions of this endocrine gland. Among TBNs the colloid goiter (CG), thyroiditis (T), and thyroid adenoma (TA) are the most frequent diseases. An evaluation of the variant of TBNs is clinically important for subsequent therapeutic interventions, as well as for more clear understanding the etiology of these disorders. The aim of this exploratory study was to examine differences in the content of bromine (Br), calcium (Ca), chlorine (Cl), iodine (I), potassium (K), magnesium (Mg), manganese (Mn), and sodium (Na) in tissues of CG, TA, and T. Thyroid tissue levels of eight chemical elements (ChE) were prospectively evaluated in 46 patients with CG, 19 patients with TA, and 12 patients with T. Measurements were performed using non-destructive instrumental neutron activation analysis with high resolution spectrometry of short-lived radionuclides. Tissue samples were divided into two portions. One was used for morphological study while the other was intended for ChE analysis. It was observed that in CG, TA and T tissues content of Br was significantly higher, while level of I was lower than in normal thyroid tissue. I accumulation in T tissue was lower than in normal thyroid and CG. Abnormal increase in Br level and decrease in I level in all TBNs might demonstrate an involvement of these ChE in etiology and pathogenesis of TBNs. It was suosed that great losses of I in thyroid with T, in contract to little reduced levels of I content in thyroid with CG and TA, could possibly be explored for differencial diagnosis of T.

Assessment of Arsenic and Copper Pollution of the Benya Lagoon, Ghana By Neutron Activation Analysis

Heavy metal concentrations in some water bodies and the soil beneath these waters. These would have detrimental consequences on these water users and consumers of the fish in that water. Instrumental Neutron Activation Analysis technique using the Ghana Research Reactor-1 was employed to find out the concentrations of two heavy metals, Arsenic (As) and Copper (Cu) in the sediments, fishes, and water collected from the Benya Lagoon in the KEEA, Ghana. Cumulatively, Copper was found to be greater in concentration than Arsenic concerning the three parts of the ecology under study. On the other hand, Arsenic was more concentrated in the sediments than Copper, and Copper was more concentrated in the water and fish than Arsenic. Cumulatively, the level of contamination of Arsenic and Copper decreased in the order fish > sediment > water. Though Arsenic and Copper were found in elevated amounts in both water and fish which rendered the Lagoon water unsuitable for human use and the fish from the Lagoon unsafe for consumption, their concentrations in the sediment were found to have a low ecological risk index on the environment.