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Aim. We study the elemental composition of samples from the gas cleaning system of an autothermic plant for the disposal of medical waste and determine their hazard class. Methodology. Fly ash samples from the elements of the gas cleaning system (air sparging system, “wet scrubber”, impeller of smoke exhaust) of an autothermal unit disposing medical waste were analyzed by an X-ray fluorescence method. The content of 30 elements, including toxic ones (Pb, Cd, As) was measured in samples. Based on the results of chemical analysis of samples from the elements of the gas cleaning system, the hazard class of the waste was calculated. Results. The analysis showed that ash from the elements of the air sparging system contains such elements as Cl, Fe, Ca, K, Ti, Zn, Cr, Mn, Pb, Ni, Sn, and Sb. The maximum metal content (Fe, Ti, Zn, Mn, Pb, Ni, Cu, and Mo) is absorbed by the scrubber cleaning system. The ash sampled from the elements of the impeller contains a high content of halogens (Cl, Br, I) and As. The presence of Cr, Zn, Ni, Pb, and Cu in the ash sampled from the elements of the impeller indicates incomplete cleaning of exhaust gases from heavy metals. The waste from the gas cleaning system of the autothermal plant for the disposal of medical waste corresponds to hazard class II (highly hazardous). Research implications. The presence of Cr, Zn, Ni, Cu, and Pb in the composition of ash taken from the elements of the impeller indicates incomplete cleaning of exhaust gases from heavy metals, a high content of halogens (Cl, Br, and I) and As indicates the possibility of environmental pollution and the risk for human health. The waste from the gas cleaning system of an autothermal plant for the disposal of medical waste corresponds to hazard class II (highly hazardous) and must be transferred to a specialized organization for neutralization or disposal in a manner that is safe for the environment and human health.

The isomeric ratios in 138Ce(γ, n)137m,gCe photonuclear reaction have been measured for energy ranges from 14 to 17, 21 to 23 and at 19 MeV end-point bremsstrahlung energies by the activation method. In order to improve the accuracy of the experimental results, necessary corrections and data analysis were made in the γ-ray activity measurements. The results were analyzed, discussed and compared with the similar data from literature to examine the role of excitation energy and the influence of channel effects. The above obtained data are the first time measurements.

A solid phase extraction method for removing polar tritiated contaminants from tritium-containing waste oils has been developed. The composition of the degradation products present in the waste oil was determined. The results indicated that upon exposure to tritium gas, fragment methyl ketones, carboxylic acids, and lactones were the main polar products of the mineral-based oil oxidation. The nonpolar fragmentation products included n-alkanes, monomethylalkanes, and acyclic isoprenoids and were analogous to those formed during \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\gamma$$\end{document}γ-irradiation of the oil. Various polar and nonpolar fragmentation products containing an isoprenoid skeleton were found to be formed via an oxidative/radiation scission of long-chain acyclic isoprenoids. Electronic supplementary material The online version of this article (doi:10.1007/s10967-016-4953-8) contains supplementary material, which is available to authorized users.

In this paper we have studied the possibility of determining the chemical elements in coal samples using X-ray fluorescence analysis and have found a relationship between the coal calorific value and its ash content with the coal moisture accounting. The amount of coal ash can be determined by the content of the basic chemical elements, such as Si, Sr, Fe, and Ca. It was concluded that the calorific value of coal can be estimated from the ash content in coal without the calorimetric measurements. These correlation coefficients were calculated for coal from several coal mines in Mongolia. The results are in good agreement with the results of chemical analysis.

This paper presents the results of a simultaneous determination of some rare earth elements and some accompanying elements of the rare-earth fields of Mongolia. Correlation connections of rare earth elements with thorium are established. Data from X-ray fluorescence, gamma activation, and classical chemical methods for analyzing mineral resources were used to find the correlation dependence between rare earth elements and thorium.

The leaves, stem, and roots of two types of shrubs (tea (Camellia sinensis) and sweet leaf (Sauropus androgynus)) and two types of herbs (vetiver grass (Vetiveria zizanioides L. Nash) and maize (Zea mays L)) and the Thucuc soil where the plants were growing were collected to be studied. The contents of 22 elements in the samples were determined by three methods: X-Ray fluorescence analysis (XRFA), gamma activation analysis (GAA), and the tracking method to study the distribution of these elements in plants and the soil-plant relationship. This study was carried out at the Flerov Laboratory of Nuclear Reactions (FLNR), Joint Institute for Nuclear Research (JINR), Dubna, Russia. The distribution of the elements in the soil-plant system was studied.

A method to produce (117m)Sn radionuclide using accelerator production route is described. A new method is proposed to separate the (117m)Sn. Specific activities and thick target yield for (116)Cd(α,3n)(117m)Sn reaction at E(α)=35MeV bombarding energy were determined. The estimated production yield of (117m)Sn was 37.5kBq/μAh for 13.16 mg/cm(2) natural cadmium-oxide target and 410 kBq/μAh for 11.07 mg/cm(2) highly enriched (95%) (116)CdO target. The method developed for separation of (117m)Sn from Cd using anion-exchange resin (Dowex -1×8, fluorine form, 400 mesh) can achieve 98% radiochemical yield of (117m)Sn with more than 99% radionuclidic purity. The estimated specific activity is 2.4 GBq/mg that can be reached with the used irradiation conditions.

The concentration of natural radionuclides and the feasibility of recovery of uranium from browncoal ash of a Mongolian cogeneration plant were investigated. The concentrations of the elements were determined by instrumental gamma-activation (IGAA) and X-ray fluorescence (XRF) analysis. Uranium from brown-coal ash was leached with an 8 M HNO3 + HF (10%) mixture. The extraction of uranium from the solution and its purification for the removal of accompanying elements were carried out on an anion exchanger. An ash sample after leaching contains neither natural radioactive elements (238U and 232Th) nor their decay products, thereby allowing for the use of the ash as a building material.

The release of trace metals from oil industry in ecosystems represents a serious hazard for the Biosphere, because of their toxicity. The objective of the study is to identify the source and evaluate the effect of key contaminants and other toxic and non-toxic bioactive elements as well as to provide the basis for improved health for human population by the use of instrumental gamma-activation analysis in combination with the X-ray fluorescence technique. The analytical work consisted in measuring trace concentrations of specific oil industry pollutants in soil and river sediments from the region of oil refinery industry in Ploiesti city, Romania. A highly sensitive photon neutron activation method based on the (γ, n) reactions for determining the concentrations of trace heavy metals in the environmental samples is applied. Additionally, the replicate samples were investigated by the X-ray fluorescence analysis. Further the results were used to develop an approach based on the geostatistical modelling to update the estimates of heavy metal concentrations on the ground in order to quantify their extent in the region in relation with the emission sources.

Molybdenum-99 was prepared by 100Mo(γ,n) photonuclear reaction on an electron accelerator, MT-25 microtron (FLNR). Natural Mo foil (9.6% 100Mo) and 100MoO3 (100% 100Mo) were used as the targets. The radiation yield of 99Mo was 3.2 kBq/(μA h mg 100Mo). Technetium-99m was isolated from the target material and concomitant radioactive impurities by an ion-exchange procedure. The possibility of preparing 99mTc generator from molybdenum carbonyl was studied. The content of radioactive impurities in the final 99mTc preparations was no higher than 10−5 Bq Bq−1.

Twenty six elements was studied preliminary i n the superficial sediments of Havana Bay using gamma activation analysis by the electron accelerator microtron MT -25 at the Flerov Laboratory of Nuclear Reactions, JINR. Samples from five zones of Havana Bay including the three coves were analyzed. The ob tained results show a close relation between the concentration levels of the studied elements and the pollution sources. Some elements (As, Ba, Ni, Pb, Cu, Zn, Fe, Cr, Mn) have high concentration levels compared to the values for other environmental marine sediments reported in the literature.

237U was produced by the reaction 238U(γ, n) on an electron accelerator, MT-25 microtron, at the Flerov Laboratory of Nuclear Reactions. For the separation of 237U and [238U, the recoil nuclei were collected by a nanostructured material, hydrated manganese dioxide (of the cryptomelane type), in the solid-solid system. From fission products, 237U was separated by ion exchange. The specific activity of the resulting 237U was 4.5 × 109 Bq (mg 238U)-1, with the content of radioactive impurities of ≤10-6 Bq Bq-1. The chemical yield of 237U was 80%.

Sorption of U(VI) with soil from the region of location of the radioactive waste repository was studied. The radionuclide 237U produced by the photonuclear reaction 238U(γ, n)237U on an electron accelerator, MT-25 microtron (FLNR, JINR), was used as tracer. The U(VI) speciation in solution at various U concentrations was calculated in the range pH 1–7 using the Speciation program.

A highly sensitive (detection limit 3 ×10-7 g g-1) procedure was developed for determination of Th in samples of soils and environmental objects. The method is based on the reaction 232Th(γ,n)231Th (T1/2 = 25.5 h). The samples were γ-irradiated for 4 h at an average electron current of 15 μA and electron energy Ee = 24.5 MeV. The Th content was estimated by recording X-ray emission of 231Th with Eγ = 25.65 keV. The X-ray spectra of the irradiated samples were recorded on an X-ray spectrometer with an Si(Li) semiconductor detector [30 mm2 area; resolution at the FeKα line (6.4 keV) 200 eV].

The effect of stress factors (small doses of radiation and maximum temperatures in the econiche of the tested plants (tmax)) as well as aging on pea seeds, both acting independently and in combination, is estimated. Here we evaluate the influence of oxidizing stress on pea seeds in the laboratory (gamma-irradiated with 7 cGy at 0.3-19.1 cGy/h, tmax approximately 30-32 degrees C) and on natural plantain seeds collected in a 30-km zone of NPP (radiation exposure approximately 15 R/h, tmax approximately 38-40 degrees C). We have mathematically modeled CAs frequencies in root seedlings meristeme by invoking an enhancing factor transmitted from cell to cell. It is shown under the stress conditions: 1) CA frequency decreases whereas the fraction of inviable seeds (IS) increases, the dependence of IS on CA frequency being inversed; 2) a stimulation of proliferation of cell was observed; 3) a bystander effect appears; 4) antioxidative status (AOS) of seeds influences on adaptation on the all levels of the organization; 5) IS increases up to 73-80% under the combined effect of radiation and heat stresses.

The present paper deals with the determination of the thorium, uranium, plutonium and neptunium concentrations by the track method using the (γ, f) reaction.

The results of the determination of radionuclide and chemical (multielement analysis) soil pollution are presented. The data on antioxidant status of plantain (Plantago major L.) in conjunction with the data on radionuclide and chemical pollution are analyzed. The most significant decrease in antioxidant activity of plant seeds was observed in areas situated along the most frequent wind direction in the region in summer 1998. It is suggested that lower antioxidant status is caused by the chronic radionuclide release on the chemically polluted territories.