[en] The tracer techniques have an important role in the study of technological processes in operating conditions of metallurgical enterprises. Radioactive samples of metallurgical materials are measured with the spectrometric system TN-4500 using two spectrometric chains. In case of multi-element labelling the complex mixture requires the use of gamma spectrometry for qualitative proof and quantitative determination of radionuclides. Multi-element labelling and the spectrometric method have been put to practical use in operating conditions of trial melts. The aim of the work is to contribute to improving the quality of metallurgical products and to the development of modern technologies. (author). 19 figs., 1 tab., 5 refs

[en] A method was developed for the determination of oxygen in steels by activation with 14 MeV neutrons. The sensitivity of the method is 1x10^-3%. The relative error is within 4 to 10% for concentrations in the region of 3x10^-3 to 0.1%. For nitrogen determination, neutron activation analysis is suitable for semi-quantitative measurements only. Silicon may be determined using this method within the concentration range of 0.02 to 0.05 in dependence on the phosphorus content. Uranium determination was also tested. (J.H.)

[en] This support study for the evaluation of the safety of geological disposal systems is aimed at identifying the requirements for software quality assurance procedures for radioactive waste risk assessment codes, and to recommend appropriate procedures. The research covers: (i) the analysis of existing procedures and definition of requirements; (ii) a case study of the use of some existing procedures; (iii) the definition and the implementation of procedures. The report is supported by appendices that give more detail on the procedures recommended. It is intended to provide ideas on the steps that should be taken to ensure the quality of the programs used for assessment of the safety case for radioactive waste repositories, and does not represent the introduction of wholly new ideas or techniques. The emphasis throughout is on procedures that will be easily implemented, rather than on the fully rigorous procedures that are required for some application areas. The study has concentrated on measures that will increase the confidence in repository performance assessments among the wider scientific/engineering community, and the lay public

[en] The corrosion resistance of austenitic CrNiMo steels in passive state is dependent on the quality of the passivating layer and on the composition of the corrosion medium. The quality of the surface layers of steels was studied by gamma spectrometry following the activation of steel samples by neutrons in a nuclear reactor. In the measured solutions obtained by controlled dissolution of irradiated material the presence was quantitatively determined of radionuclides ⁵¹Cr, ⁵⁴Mn, ⁵⁸Co, ⁵⁹Fe and ⁶⁰Co. The method of radioactive tracers was experimentally used for investigating the kinetics of the decontamination and pickling processes, of point corrosion and the composition of the surface layers of steel following diverse types of heat and chemical treatment. (author). 7 figs., 1 tab., 13 refs

[en] The sources are discussed of radioactive contamination of water and processes are indicated affecting the occurrence of radionuclides in ground water, mainly sorption and desorption of radionuclides in the soil and soil properties in radionuclide migration. An analysis is made of the current radioactivity of surface and ground waters of the Rye Island, a fertile agricultural area in southern Slovakia. The gross alpha and beta activities and the concentrations of ⁹⁰Sr, ¹³⁷Cs, Ra and U were determined in water samples. The values found are lower than the maximum permissible concentrations. The gross beta activity of samples has increased in the past ten years. (H.S.)

[en] Time resolved absorption spectra of trapped electrons generated in pulse irradiated polypropylene film containing irganox 1076 are investigated at ∼100 K. Antioxidant influences the yield and decay of near-ir electrons in the matrix under consideration

[en] Phase analysis provides information on micropurity and the phase composition of steel such as have effect on its utility properties. The method of radioactive tracers was used to study the process of direct chlorination on a routine device for separating oxide inclusions. The spectrometric method was used for measuring samples of material processed on key moments of the process. The efficiency of the separation of oxide inclusions was studied using radionuclide ¹⁴¹Ce. The method of direct chlorination was used to process steel slag with labelled CeO₂, the Al-Ce alloy for the study of steel deoxidation and steel samples containing radioactive ceric oxide in form of inclusions. Also studied was the behavior of synthetic carbides of tungsten, molybdenum, chromium and tantalum during chlorination, using radionuclides generated during the activation of carbides by neutrons. (author). 1 fig., 2 tabs

[en] The facts of the project for the two units WWER-440/W213 are presented: approach; safety related retrofitting measures (fire protection, earthquake-proof, system improvements, measures regarding electrical engineering, instrumentation and control); financing concept (loaner EBRD in London, Euratom, EIB, EDF, BAG); project structure (project company EMO Electrarne Mochovce), state of project, Since March 1995 the situation is uncertain; when the Slovakian government asked for a ''pause for reflection'' to consider cost-saving ways for completion (internationally estimated financial requirements amount to 1.466 million DM) this led to well understandable irritations on the part of all interested parties. (HP)

[en] A test body was devised for the radiometric determination of solubility of alloy additions in liquid steel. The body, made of the re-melted alloy addition tested, is of a regular (cubic or spheric) shape and is fitted with a bore accommodating a suitable radiotracer in the centre of the body. The tracer is protected against premature release by iron powder and a screw closure, whose outer part is bent to form a manipulation handle for the whole test body. Bodies of cubic shape, edge 50, 75, 100 and 130 mm, fabricated from FeCr, FeMn, SiMn and FeTi additions and accommodating ¹⁹⁸Au, ⁵¹Cr, ^110mAg, ¹⁸²Ta, ⁹⁹Mo, ¹⁸¹Hf and ⁶⁰Co radiotracers in various combinations such that the total activity did not exceed 3.7 GBq, were used with success. (P.A.). 1 fig

No abstract available