Extraction of strontium using an irradiated extraction agent of crown structure

The partition coefficient of strontium upon its extraction from the aqueous solutions of picric acid into chloroform containing DC-18-crown-6, B-15-crown-5 after their exposition to gamma radiation has been studied. A significant decrease of the partition coefficient in the studied range of doses 10–70 kGy was observed. This effect can be attributed to the radiolytic products of chloroform. The radiation destruction as well as dehydrogenation of crown ethers were not observed.     

Determination of239, 240Pu in environmental samples from surroundings of the atomic power station Jaslovske Bohunice

The development of a rapid and reproducible method for the separation of plutonium from soil samples is described. Tetravalent plutonium is extracted from 8M HNO₃ into 30% Aliquat-336/toluene mixture. Uranium and thorium are removed with nitric and hydrochloric acid washes. Plutonium is backextracted with HCl–H₂C₂O₄ and HCl–HF solutions. Plutonium is coprecipitated with NdF₃ and filtrated onto a 0.1–0.2 m membrane filter to prepare a source for -spectrometry. The chemical yields of separation are about 50–60%.     

The radiolysis of bis/1,2-dicarbollyl/cobalt/III/ acid in H2O−CCl4 two-phase system

The radiation-induced oxidation of bis/1,2-dicarbollyl/cobalt/III/ acid to 8-monohydroxy-, and 8,8-dihydroxy-derivatives was observed in two-phase system of 4 to 96 vol. % of CCl₄ and H₂O. Carbon tetrachloride increases the radiation yields of the oxidation of the acid in the investigated dose region, nature of the radiolytic products being the same. The partial radiation yields in the system were ascertained.     

Anaerobic Degradation of PCB in Soils

Abstract

The anaerobic degradation of PCB in loamy and clayey soils containing indigeneous microflora was studied. The anaerobic conditions were created by an argon atmosphere in the flasks containing soil flooded by a liquid medium with glucose. GC-ECD analysis of soil extracts after 40 day incubation showed, in addition to the concentration changes of the less chlorinated PCB congeners, a significant decrease in the concentration of highly chlorinated congeners in both soils. The results indicate that in both soil types reductive dehalogenation of PCB congeners was encountered.     

2. Internationale Konferenz iiber Methoden der Darstellung and Aufbewahrung markierter Verbindungen

Es wurde die Verteilung von ¹³¹J im Zeitraum von 1/2–24 h nach einer einmaligen Röntgenbestrahlung mit 0,21 C/kg verfolgt, wobei das Radiojod zu zwei verschiedenen Zeitpunkten nach der Exposition verabreicht wurde; 2 Stunden nach der Exposition bei der Gruppe T₂ und 18 Stunden bei der Gruppe T₁₈. Unterschiede in der Verteilung des Radiojods bei den Kontroll- und Versuchstieren weisen auf pathophysioloyische strahlenbedingte Organveränderungen hin.     

Adsorption of alkali and alkaline earth radionuclides on zeolite from water solutions

The adsorption of cesium and strontium ions from water solutions on zeolite has been investigated in presence of sodium, potassium, magnesium and calcium ions. Distribution ratios of cesium and strontium on the zeolite were determined in solutions of various compositions and solution volume to sorbent weight ratios (batch factor). Breakthrough curves for zeolite layers are reported.     

Fell topology on the space of functions with closed graph

LetX andY beT ₁ topological spaces andG(X, Y) the space of all functions with closed graph. Conditions under which the Fell topology and the weak Fell topology coincide onG(X,Y) are given. Relations between the convergence in the Fell topologyτF, Kuratowski and continuous convergence are studied too. Characterizations of a topological spaceX by separation axioms of (G(X, R), τF) and topological properties of (G(X, R), τF) are investigated.     

The radiolysis of aqueous solution of bis/1,2-dicarbollyl/cobalt/III/ acid

The radiation-induced oxidation of bis/1,2-dicarbollyl/cobalt/III/ acid by OH radicals in deaerated/aerated aqueous solutions has been investigated. 8-Monohydroxy-, and 8,8-dihydroxy-derivatives have been identified as products of the -radiolysis. For the different conditions the following radiationchemical yields were observed: in the presence of N₂ atmosphere G/_OHDCC/=1.58, in aerated solution 2.11 and 3.04 in a solution saturated with CCl₃.     

Study of thermal properties of thallium hexavanadate

A DTA study of the thermal properties of Tl₂V₆O₁₆, showed that its structure is not decomposed up to 475 °C. It melts at 505 °C. Tl₂V₈O₂₁ and Tl₃V₅O₁₄ crystallize successively from the melt.     

B-Halogen derivatives of the bis(1,2-dicarbollyl)cobalt(III) anion

The halogenation of (C₂B₉H₁₁)₂Co^?Cs⁺ by elemental halogens in alcohol and γ-radiation-induced halogenation by CHBr₃, CH