[en] The 12th meeting was attended by 113 participants coming from 21 countries and from EURATOM and IAEA.42 reports were presented orally within 10 sessions dealing with 5 main topics: 1) programs(5); 2) fuels(12); 3) reactor conversions(17); 5) high performance neutron sources(4); 5) others(4). (HP)

[en] The 12th meeting was attended by 113 participants coming from 21 countries and from EURATOM and IAEA.42 reports were presented orally within 10 sessions dealing with 5 main topics: 1) programs(5); 2) fuels(12); 3) reactor conversions(17); 5) high performance neutron sources(4); 5) others(4). (HP)

[en] Cooler Synchrotron and Storage Rings and their circulating very intense cold beams with high phase space density allow the study - in the nonperturbative QCD regime - of hadronic processes which cannot be investigated by other means. Measurements at small angles including zero degrees permit the study of meson production near and at threshold, in particular in unique spin states, because both polarized beams and polarized, windowless targets can be used. Hadron spectroscopy at small angles allows among other studies crucial measurements of charge-exchange processes and break-up studies for investigation of e.g. the deuteron wave function at high momenta, in a test of quark effects, and studies of the excitations of the nucleon. The scope of the seminar is to review the first results obtained at Cooler-Storage Rings, to discuss the experimental approaches and the theoretical models and predictions for meson production including strange hadrons and their interactions in nuclear matter in order to develop the best strategy for future work. See hints under the relevant topics. (orig.)

[en] Global changes affecting the earth are at the forefront of public interest, possibly caused by climate alterations amongst other things. The public expects appropriate measures from politics to successfully adapt to unavoidable climate changes. As well as an investigation into the causes of climatic changes and the corollaries between the different scientific phenomena, the effects on the economy and society must also be examined. The Federal Minister for Research and Technology aims to make a valuable German contribution to international Global Change Research with the focal point ''Effects of Climate Changes on the Ecological and Civil System''. The aim of the workshop was to give an outline of current scientific knowledge, sketch out research requirements and give recommendations on the focal point with regard to the BMFT. (orig.)

[en] The main objective of the MTR-Loop is for testing the specimens of MTR fuel element uprated conditions with respect to the normal conditions of the reactor fuel elements. It is intended to verify the suitability of the fuel elements for operation in a research reactor under preset temperature and pressure conditions. The most important part of the MTR loop is the test section. The fuel elements to be tested are positioned in the test section. For heat removal there is a cooling water flowing through the test section. On this paper the description of the MTR-Loop is described. Installation of the MTR-Loop will be performed in the middle of 1990. In order to facilitate the investigation of fuel behaviour and performance of the new fuel elements the supporting facilities are also already available in the RSG-GAS. (orig.)

[en] The progress of the Reduced Enrichment Research and Test Reactor (RERTR) Program is described. After a brief summary of the results which the RERTR Program, in collaboration with its many international partners, had achieved by the end of 1988, the major events, findings, and activities of 1989 are reviewed. (orig.)

[en] The 2 MW Rhode Island Atomic Energy Commission reactor is required to convert from the use of High Enriched Uranium (HEU) fuel to the use of Low Enriched Uranium (LEU) fuel using a standard LEU fuel plate which is thinner and contains more U-235 than the current HEU plate. These differences, coupled with a desire to upgrade the characteristics and capability of the reactor, have resulted in core design studies and thermal hydraulic studies not only at the current 2 MW but also at the maximum power level of the reactor, 5 MW. In addition, during 23 years of operation, it has become clear that the main uses of the reactor have been neutron scattering and neutron activation analysis. The requirement to convert to LEU presents an opportunity to optimize the core for the utilization and to restudy the thermal hydraulics using modern techniques. This paper presents the current conclusions of both aspects. (orig.)

[en] As one of possible future programs for the Kyoto University Research Reactor (KUR), the Research Reactor Institute of Kyoto University (KURRI) has a plan for core conversion to the use of low-enriched uranium (LEU) fuel. A feasibility study for this conversion started in November, 1983, as a part of the joint study between KURRI and Argonne National Laboratory (ANL).Thermal-hydraulic analysis on the use of LEU fuels in the KUR was performed in 1984, and neutronic calculation in 1985. The conversion is to be from the current highly enriched uranium HEU (93.15%, UAl-alloy 0.586 gU/cm3) to LEU (19.75%, U3Si2-Al, 3.2 gU/cm3). The results indicate that the core can be converted without significant difficulties. Prior to the safety review application for the full core conversion with LEU silicide fuel, we are planning to demonstrate the use of two full size LEU suicide fuel elements among the current HEU elements. The safety analysis report for the two-element demonstration is to be submitted to the government shortly. The full core conversion is anticipated in 1993.(author)

[en] NUR is a new MTR reactor located in Argelia which became critical in march 1989. It is loaded with a 19 plates LEU Fe. This paper contains: a) Reactivity measurements in the first cores technical information about the Fe and some other data necessary for performing cell and reactor calculations b) calculation comparisons with the measured values (2-D and 3-D calculations) with an statistical analysis of the data set from the control rod calibration. (orig.)

[en] The transfer of fuel element supply contracts, the corresponding Al-materials, structure parts, documents, uranium metal, customers related know-how, tools and equipment from NUKEM to CERCA has been completed, thus now giving a high flexibility for CERCA's workshop to fabricate and inspect large quantities of several types of fuel elements simultaneously. Based on this fact, on strategic planning for the next couple of years and on the fact that after 10 years of RERTR program the necessary high density fuel has been successfully developed and implemented, 'business as usual' in the field of fabrication has well become possible. The RERTR community should now use the great chance to concentrate all its efforts on problems which still strongly influence the fabrication and the use of MTR fuel elements: supply of enriched uranium,reprocessing capabilities and politics, transports of nuclear materials. (author)