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- Author or Editor: I. Penev x
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Abstract
Dy content has been determined by INAA in the Bulgarian standard rocks BV, GV, DM, MrA, OgG, OZnO and in the IAEA standard reference materials SL-1, SOIL-5, and SOIL-7. Results are compared with Dy values obtained by interpolation of the chondrite-normalized contents of other REE in these samples.
Abstract
A scheme for INAA of pottery is proposed. The combination of 3 irradiations-epithermal and pile (short and long time) and 6 measurements (2 times after each irradiation) enables the determination of Al, As, Au, Ba, Br, Ce, Co, Cr, Cs, Dy, Eu, Fe, Hf, K, La, Lu, Mg, Mn, Na, Nd, Rb, Sb, Sc, Si, Sm, Ta, Tb, Th, Ti, U, V and Yb. The accuracy and precision of the method is evaluated by analysis of standard reference materials (USGS-BCR-1, USGS-W-1, ZGI-TB). The applicability of the method is demonstrated by analysis of 15 sgraffito ceramics from XV–XVIII cc. from Tzarevetz, Veliko Tirnovo (Bulgaria). The results from the clustering of the analytical data are presented and discussed.
Abstract
A scheme for instrumental neutron activation analysis of ancient and medieval glasses is proposed. The combination of three irradiations (short time, pile and epithermal) enables the determination of 34 elements. The accuracy of the method is evaluated by analyzing two glass standard reference materials. Results from the analysis of three glasses from different times are presented.
Abstract
A method for simultaneous neutron activation determination of Al, Mg and Si using two irradiations in a nuclear reactor—the first one with epithermal and the second one with pile neutrons is proposed. The applicability of the method is demonstrated by the analysis of standard reference materials—rocks, glass, as well as of archaeological finds from medieval glass and sgraffito ceramics.
Abstract
The results from INAA of 3 of the standard materials /Perlman and Asaro standard pottery, Ohio Red Clay and Lefkandy Brick/ used in archaeometric investigations of pottery are presented. The values obtained for 32 determined elements are compared with the analytical data of other investigators. The accuracy of analysis and applicability of the standards are discussed.
Abstract
Extraction procedure for mercury, arsenic, cadmium, copper and zinc in biological materials is proposed. Mercury and copper are extracted with dithizone followed by the separation of mercury with tri-octyl-amine (TOA). Arsenic, cadmium and zinc are extracted as diethyldithiocarbamates. The procedure is applied for the analysis of some reference materials and autopsy human samples of kidneys, liver, heart, spleen and hair.
Abstract
The possibility of using human hair as a monitor for the pollution of the environment with metals is discussed. Analyzed are 15 cases by means of Instrumental Neutron Activation Analysis. Elements Se, Cu, Ca, Na, Mn and S in Bulgarian hair are compared with those from other countries. Analyzed cases are divided into two groups: metal burdened and nonburdened. A difference in Na, Ca and Mn content in hair of both groups is observed. A value of Mn is outlined which indicates with a high probability the metal burden of a person.
Abstract
Vanadium was determined in adrenal gland, brain, ileum, kidney, liver, lung, muscle, myocard, skin, spleen, gonads, thyroid, and tibia of rats fed with normal diet and exposed to high vanadium doses in drinking water. Both radiochemical neutron activation analysis (RNAA) and instrumental neutron activation analysis (INAA) were employed. The RNAA procedure consisted in dry ashing samples prior to irradiation and vanadium separation from the irradiated samples by extraction with N-benzoyl-N-phenylhydroxylamine (BPHA) in toluene from 5 mol·l–1 HCl. Vanadium accumulation as a function of a type of the tissue, exposure time, sex of rats, and administration of V(IV) or V(V) was studied. For quality assurance purposes, the biological (standard) reference materials NBS SRM 1571 Orchard Leaves, NBS SRM 1577a Bovine Liver, IAEA H-4 Animal muscle, and Bowen's Kale were analyzed.
Abstract
The aim of this work was to provide an experimental basis for assessing intakes of an industrial actinide-bearing dust from measurements of60Co and137Cs in the body or urine. Whilst these radionuclides comprised 72% and 19% of the radioactivity present, greater than 90% of the committed effective dose will result from the low concentrations of the actinides present, 0.4%. To assess the dose coefficient for the dust and predict the biokinetics of60Co and137Cs in workers, absorption parameters for transfer from lungs to blood obtained from an animal study were combined with information on particle deposition and clearance from the ICRP human respiratory tract model and with tissue distribution and excretion data from the most recent systemic models. All other radionuclides were assumed to have Type M absorption characteristics. The dose coefficient for the dust, 1.29·10–7 Sv·Bq–1 was estimated to contain 113 kBq60Co, 29 kBq137Cs and 0.64 kBq of the actinides. The predicted retention and excretion characteristics of60Co and137Cs in workers after acute or chronic exposure to the dust suggested that measurements of these radionuclides in the body or urine could detect intakes equivalent to a few percent of an annual dose limit of 20 mSv·y–1.
