[en] The control and reduction of radioactive contamination of the biosphere is a worldwide problem. The conclusion from studies of ⁹⁰Sr and ¹³⁷Cs isotopes incorporation in human body is that the quantity of these radioisotopes depends not only on the biological contamination of the air-water-soil-plants-animals-man chain but also on many other factors including geographical location, meteorological circumstances, the mechanical structure and chemical composition of soil, cultivation techniques, types and ages of plants, decontamination processes, animal species and ages, the age and nourishment habits of people. Through the evaluation of these factors new decontamination methods are proposed. (P.J.)

[en] On the basis of several geological phenomena the theory of Kuroda on the existence of the natural reactor may be considered as confirmed. The existence of the Oklo phenomenon is supported by several facts in connection with the changes in uranium concentration. The output of the natural reactor is equal to that of an experimental reactor. It is also an evidence for the spontaneous fission of heavy elements and the spontaneous fusion of light elements in nature (the process of energy generation in the stars). The neutron bomb, or the Enhanced Radiation Warhead as called originally, has a high specific radiation effect as compared with other nuclear warheads. The possibilities of protection are based on the radiation attenuation factors of various materials. (R.P.)

[en] The main trends of nuclear power researches in the Federal Republic of Germany are analysed. All aspects of the nuclear power engineering are touched and the activities of several research institutions are outlined. (R.J.)

[en] The potential applications of activation analysis in water chemistry are discussed. The principle, unit operations, the radiation sources and measuring instruments of activation analysis are described. The sensitivity of activation analysis is given in tabulated form for some elements of major importance in water chemistry and the elements readily accessible to determination by measurement of the spontaneous gamma radiation are listed. A few papers selected from the recent international professional literature are finally reviewed, in which the authors report on the results obtained by activation analysis applied to water chemistry. (author)

[en] A new complex device has been elaborated for the investigation of the duration of bearings in the Institute of Isotopes of the Hungarian Academy of Sciences. The simultaneous determination of wear by an isotopic method the coefficient of friction by means of a Wheatstone bridge and the bearing temperature by means of a thermoresistor is described. Dynamic loading and variable revolution per minute are applied to produce a forced wear of the bearings. The isotopically labelled wear products are removed by oil and the collected sample is measured by a scintillation detector. Wear of a steel axle in plastic housing and plastic coated axle in cast iron housing was determined. (V.N.)

[en] In order to get the required water quality the secondary sides of the steam generators have to be blown down. The blown down water quantity of the 1300 MW power plant is led through a 10 kg/s throughput capacity equipment consisting of two branches provided with an electromagnetic filter each and a mixed bed filter cleaned back to the cycle. To diminute the operational temperature of 280 deg C to the cleaning temperature of 50 deg C an evaporator and a condensate cooler are switched before the equipment. The electromagnetic filter precipitates the ferromagnetic iron oxides (magnetite) with a high filtering velocity. The reflashing by a demagnatized half-filling lasts about a minute. The regeneration is performed by sulphuric acid and sodium hydroxide. (author)

[en] The results of the 12th International Congress on Cancer are summarized. The optimal program of treatment consists of surgical, chemical, immuno- and radiotherapy in combination or in practical order. New radiation sources assure effective therapy. The possibility of the exact localization of tumours has been improved. New methods are available for increasing the sensitivity of irradiation. As a result, radiotherapy can be used more effectively as part of a complex treatment. New methods of therapy-planning have also been developed. (L.E.)

[en] The possibilities of neutron therapy are given. On the basis of literature the interactions of the neutron and living tissues as well as the results of clinical applications of fast neutrons and the neutron sources are discussed. Finally, a brief summary of the radiobiological observations carried out in the IBR-30 reactor of the Dubna Atomic Research Center is given. (H.E.)

[en] The following tasks concerning the energy production must be solved: determination of nuclear data at suitable accuracy; measurement of burn up in nuclear fuels; development of dose measuring techniques; examination of purity by nuclear analytical methods; examination of the surface properties of solids; controlling the consumption of nuclear fuels (safeguards); studying fusion reactions by means of magnetic field and laser radiation. The main directions in Hungarian nuclear investigations are discussed (reprocessing of burnt-out fuels, pollution, dosimetry). (V.N.)

[en] The dose distribution for ⁶⁰Co irradiation treated mammary cancer cases was studied. The three-dimensional distribution of the radiation was determined by computer calculations. (H.E.)