[en] Space-technology can in the future help to solve two burning global problems of mankind: global warming and the storage of radioactive waste. In the space technological solution of these problems the celestial mechanical Lagrange points of the Sun-Earth and Earth-Moon systems can play an important role. Therefore the celestial mechanical theory and computer simulation of the nature of Lagrange points have great importance in some aspects of the protection of the environment, too. The two examples given, propose: storage of radioactive wastes in the stable Lagrange points L₄ and L₅ reduction of the global warming by positioning satellites with large mirrors in the collinear Lagrange point L₂ thus shadowing the incoming solar radiation. (orig./HM)

[en] The test rig IFA-657 contained four CT specimens prepared from high fluence, high yield strength 304 SS. Three of the CTs were prepared from Chooz A 304 SS with an irradiated YS of 890 MPa. The fluence for two of the CTs (CT3 and CT4) was 2.5 x 10²² n/cm² and the fluence of the third (CT2) was 1.2 x 10²² n/cm². The fourth CT (CT1) was prepared from Oskarshamn 2 304 SS (YS 745 MPa and fluence 0.9 x 10²² n/cm².). During in-pile testing over three 100-day irradiation cycles, the specimens were exposed to a coolant temperature of 335 C and PWR primary water chemistry conditions (with 2-3 ppm Li / 1000-1200ppm B and 2-3 ppm H₂). Some of the specimen cracking response was ambiguous and in order to screen the results, criteria were set for either selecting or rejecting the data. Crack growth data that were accepted were computed over time intervals > 100 hours, with rates > 10-8 mm/s and crack length increments > 0.01mm. Despite the screening, the crack growth responses of the three Chooz A CTs were not easily interpretable: CTs 2 and 3 were initially loaded a stress intensity level of ∼6.5-7.5 MPaνm and the dcpd measurements made during the first irradiation cycle indicated similar apparent growth rates (in the range 3x10^-8 - 1x10^-7 mm/s) for both specimens. Later post irradiation examination inspection of the fracture surfaces, however, did not show any evidence of environmentally assisted cracking having occurred in CT3. As the test progressed, the K level on CT2 was increased (to 8, 15, 18 and finally 37 MPaνm), with no apparent effect in producing enhanced growth rates. A limited data set was produced for CT4, with crack growth rates ranging from 2x10^-8 - 1x10^-7 mm/s being recorded at a K level of ∼14-15 MPaνm. Overall, little effect of K was observed for the Chooz A specimens and a possible explanation for the absence of a CGR-K dependency, yet to be confirmed, could be the presence of high Si segregation at the grain boundaries of this material. For both CT2 and CT4, load cycling and other load perturbations had a marked effect on cracking response. Small (of the order 025-0.5 MPaνm) increases in load resulted in intervals of rapid crack extension while cycling produced step-like increments in crack length. Similar observations have been reported in other studies on high yield strength materials and it remains unclear as to whether the steps are due to real, rapid crack advance or due to the breaking of uncracked ligaments of material. The most reasonable cracking response was obtained for CT1, prepared from the Oskarshamn 2 304L SS. At applied stress intensity levels of 13.6-17 MPaνm, crack growth rates of ∼2.4x10-8 to ∼1.2x10-7 mm/s were calculated for the specimen and the K dependency of K 2.6 is comparable to the K dependencies reported in the literature. The IFA 657 CTs exhibited growth rates that were similar to those reported for unirradiated cold worked materials of similar yield strength, tested at low potential. The crack growth rates measured on the specimens in this study were also compared with crack growth rate results from irradiated specimens that were tested in BWR conditions at high and at low potential. At low potential, the crack growth rates measured in IFA-657 were higher than those measured in BWR conditions, where temperatures are also lower; i.e. the higher rates measured for the PWR test are attributed primarily to the difference in test temperature. (Author)

[en] Short communication. 5 refs

[en] Poster presentation

[en] Redox reactions induced by light and electron pulse have been studied in aqueous solutions of mixed ligand iron(II) complex cyanides. The short lived intermediates have been identified by time resolved specroscopy, the results of detailed kinetic analysis have been discussed. (author) 6 refs.; 3 figs.; 2 tabs

[en] The modeling and analysis of hybrid systems is a recent and challenging research area which is actually dominated by two main lines: a functional analysis based on the description of the system in terms of discrete state (hybrid) automata (whose goal is to ascertain conformity and reachability properties), and a stochastic analysis (whose aim is to provide performance and dependability measures). This paper investigates a unifying view between formal methods and stochastic methods by proposing an analysis methodology of hybrid systems based on Fluid Petri Nets (FPNs). FPNs can be analyzed directly using appropriate tools. Our paper shows that the same FPN model can be fed to different functional analyzers for model checking. In order to extensively explore the capability of the technique, we have converted the original FPN into languages for discrete as well as hybrid as well as stochastic model checkers. In this way, a first comparison among the modeling power of well known tools can be carried out. Our approach is illustrated by means of a 'real world' hybrid system: the temperature control system of a co-generative plant

[en] To monitor the electron beam therapy some immunological parameters of breast cancer patients previously undergone surgery were tested before, during and after irradiation. Immune complex levels measured by complement consumption technique were not altered by irradiation. Killer cell activity tested in so-called antibody dependent cellular cytotoxicity (ADCC) capacity assay showed a marked decrease in some cases. Based on the phagocytic capacity of the granulocytes the patients could be divided into two groups: one with declining activity and another with rising activity: The majority of the patients (22/45) were humoral leukocyte adherence inhibition (H-LAI) negative before and during irradiation. Those showed positive H-LAI indices before electron therapy had unchanged (7/45) or decreasing (9/45) tendencies during the observation period. Further study is needed to establish the clinical relevance of these in vitro assays used by us. (orig.)

[en] Currently, approximately 40% of the electricity in Hungary is produced by nuclear reactors. Safe and economic operation of the nuclear plant will be also supported by nuclear safety research during the extended lifetime of the plant. The Hungarian Sustainable Nuclear Energy Technology Platform was launched in 2010, with the aim of influencing the agenda of nuclear energy research and development activities in Hungary and to participate in its coordination. The agenda should take into account the needs related to a) the lifetime extension of Paks nuclear power plant (4 VVER-440 units), b) the realization of new nuclear units, c) the closing of the fuel cycle and the development of Generation IV reactors. Launching the platform is due to the needs and necessities in Hungary, influenced by the European development as well. The above three goals of answer the requirements of the nuclear industry and serve as basis for the future development. The lifetime extension of the existing units requires the maintaining of the high safety level reached until now and also leads to some important further modifications as the refurbishment of the process control system. Though no final decision has been made concerning new units, it is expected in the near future and licensing and tendering may already start. Later the Platform should facilitate the transfer of new technology to Hungary. The strategy concerning the nuclear fuel cycle should be reformulated due to the lifetime extension and the appearance of new units. Closing the fuel cycle would mitigate the risks related to the radioactive waste management and would promote the better utilization of the Uranium resources. The use of fast reactors may solve both problems. The majority of the candidate reactors for Generation IV are fast reactors. An important long term task of the platform is to promote the research and development related to fast reactor technology in Hungary. The paper presents the medium and long term goals of the national nuclear R and D program and recent activities in the field of fuel cycle research within the Visegrad Group. (author)

[en] The paper presents estimation on the quality and quantity of low and intermediate level radioactive wastes at Paks Nuclear Power Plant. An analysis is given on the effects of the 2003 event at Paks and on the power increase of the reactors. (TRA)

No abstract available