[en] The time necessary to achieve the equilibrium ratio of strange to non strange quarks in heavy ion reactions is estimated in the framework of perturbative QCD. It is found, in the present approximation, to be much larger than the total collision time of even a central U+U collision at Esub(LAB)=2.1 GeV/nucleon bombarding energy. (author)

[en] The composite particle production in heavy ion collision is calculated in the framework of a hadrochemical model. A critical comparison is performed between the produced entropy and the observables. It is shown that the observed d/p ratio is not the proper quantity to determine the specific entropy, because this ratio strongly depends on the volume of the deuteron. (author)

[en] The first results of thermocurrent dosimetry (TCD) measurements are presented which have been carried out with synthetic optically pure sapphire. Parameters of the experimental apparatus designed for irradiation of speciments and measuremets of thermocurrents are shortly described ²⁴¹Am served as a radiation source. Typical TCD curves are presented which have been obtained after irradiation up to 5x10^-5 and 5x10^-4 C/kg and heating in the temperature range from 100 to 400 deg C. The background noise is due to surface polarization. The merit of TCD consists in measuring doses using electric values, thus ensuring the simplicity of measurements and adequate reproducibility of results

No abstract available

[en] In addition to leakage detection it could be useful to examine the cladding surface for corrosion and mechanical damage in order to locate the source of leakage or to anticipate loss of integrity. The check of non-dismountable assemblies could also be informative. Highly radioactive and densely packed spent fuel is hardly accessible, only remote viewing is possible either in wet or dry storages. Television cameras and periscopes or telescopes are in general utilized for such purposes, in most cases designed for underwater use. We developed an Underwater Telescope for such purposes and have broad experience in the inspection of LWR fuel assemblies in storage ponds and of other reactor components and structures. Experiments with HWR spent fuel assemblies are also in course. Visual examination of surfaces can be carried out down to about 10 m water depth with very good resolution and image stability, therefore, in addition to direct viewing or video recording photographs can be taken for documentation and comparison. The device has no radiation sensitive element at the front end, so both remanent damage and temporary malfunctioning is completely avoided. The mechanical design allows to set up arrangements meeting the actual requirements: various lengths, diameters, vertical or horizontal viewing, special lamps and other options are available. The design and possible applications are briefly illustrated and the experience obtained in the examination of corrosion and other defects is reported. (author). 4 refs, 6 figs

[en] The widespread use of high intensity radiation sources, reactors and nuclear power plants requires the use of accident dose meters. An aluminium oxide ceramic dose meter has been developed. Because of its low atomic number and its small dimensions, it is suitable for dosimetry of gamma and mixed gamma-neutron radiation fields. The Al₂O₃ dose meter (diameter 6mm, thickness 1mm), containing Mg and Y activators gives a linear response between 1 and 2x10⁵ rads. The peak in the emission spectrum of the Al₂0₃ dose meters constructed by us is near to 4400A. Two peaks can be observed on the glow curve at 250 and 290⁰C. The low temperature peak is not significant. The reproducibility of dose meters is within +-10%. Fading is less than 10% at room temperature for 24 hours, and not higher than 20% in 240 hours. The dose meters are suitable for repeated use provided they are annealed before use at 600⁰C for 2 hours. (author)

[en] We develop an (r,k) phase space description of waves in plasmas by introducing Gaussian window functions to separate short scale oscillations from long scale modulations of the wave fields and variations in the plasma parameters. To obtain a wave equation that unambiguously separates conservative dynamics from dissipation also in an inhomogeneous and time varying background plasma, we first discuss the proper form of the current response function. On the analogy of the particle distribution function f(v,r,t), we introduce a wave density N(k,r,t) on phase space. This function is proven to satisfy a simple continuity equation. Dissipation is also included, and this allows us to describe the damping or growth of wave density' along rays. Problems involving geometric optics of continuous media often appear simpler when viewed in phase space, since the flow of N in phase space is incompressible. Within the phase space representation, we obtain a very general formula for the second order nonlinear current in terms of the vector potential. This formula is a convenient starting point for studies of coherent as well as turbulent nonlinear processes. We derive kinetic equations for weakly inhomogeneous and turbulent plasma, including the effects of inhomogeneous turbulence, wave convection and refraction. (author)

[en] Presented are experimental results of comparing LiF - teflon, LiF - sintered pillets and photographic film personnel dosimeters designed for measuring gamma-radiation doses. Using the findings of about 1000 comparative measured doses in the range of 10-1300 mR, and on the correlation of measurements using different dosimeters. In terms of sensitivity it is concluded that thermoluminescent dosimeters are more reliable than film ones. The dosimeters in question are employed in a combined assembly, designed for measuring all types of radiation

[en] A short review of the application of isotope techniques in environmental protection is given. Examples illustrate the use of tracer techniques and activation analysis in food and environmental quality protection, in the measurement, detection and control of pollutants as well as in other procedures. (Sz.J.)

[en] The report introduces the Institute of Isotopes and describes research and services related to nuclear safeguards and forensics. Available equipment and facilities are listed