[en] We found that a highly-oriented-pyrorytic-graphite, 'HOPG', enhances the neutron flux for the following Si crystal more than 3 times. This effect can be generally utilized actually in the field of precise neutron optics. This phenomenon seems to be explained by the deviation of the lattice parameter in the HOPG

[en] In accordance with the Japanese law, Nuclear and Industrial Safety Agency (NISA) verifies the safety of nuclear installations. NISA's inspectors for safety management of nuclear installations are stationed at nuclear installations throughout the country to survey installations such as the main control room and turbine generator on a daily basis and, verify the operating status of each facility. From October 1st, 2003, Japan Nuclear Energy Safety organization (JNES) also started to perform part of inspections shown above basing on share with NISA. Now, under the above-shown inspections, a lot of significant data continue to be produced, but those data exist individually and have not been efficiently utilized in the nuclear regulation. NISA and JNES are, therefore, developing the data base system for the inspectors of nuclear installations. The first data base system started the development to assist the inspectors in 2001, and now, under servicing and improving. The second data base system is being developed, and will store most of sources including inspection reports, government's evaluations. The data will be able to be transmitted to the first system through network. (author)

[en] Comparative experiments using 2.5 MeV electron irradiations to Fe-Cu model alloys have been undertaken to study the gamma-ray induced hardening of RPV steels. Hardness changes induced by Cu precipitates for Fe-0.6%CU model alloy was confirmed. The difference between electron and neutron irradiation hardening was very small on a dpa basis except for very low dpa

[en] A computer code was developed for analyzing transport of short-lived fission products released from a failed fuel in the sodium coolant. For example, the transport analysis was performed for a 100 mw(t) LMFBR. 5 refs

No abstract available

[en] A series of the works recently conducted for safety evaluation of the experimental fast reactor ''JOYO'' gave favorable results for further power increase from the previously authorized power of 50 MWt. Major technical topics associated with the recently conducted safety evaluation are discussed. Safety examination given by the regulatory authority for increasing reactor power to two levels (75 MWt for Mark-I core and 100 MWt for Mark-II core) was carried out for about one year from September 1977 and approval by the regulatory authority was granted on 20 September 1978. 2 refs

[en] Short communication. 1 ref

[en] We have examined in-plane orientation of CeO₂ buffer layers on c-plane and tilt-c-plane sapphire substrates. The tilt angles are 5 deg., 10 deg. and 15 deg., which are defined as the angles between the c-plane and the surface planes of the sapphire substrates (called 5 deg., 10 deg., 15 deg. tilt-c-plane substrates). The films were prepared by inductively coupled plasma sputtering. The in-plane orientation of the films was measured using X-ray phi-scan. phi-scan peaks of films fabricated on c-plane substrates appeared every nπ/6 or nπ/12 (n: integer), showing 12-fold or 24-fold symmetry. The in-plane orientation is influenced by the hexagonal symmetry of the sapphire c-plane. The degree of film orientation depends on the substrate temperature during preparation. On the other hand, we found weak 4-fold symmetry for films fabricated on 10 deg. and 15 deg. tilt-c-plane substrates. This suggests that we can obtain CeO₂ films with perfect 4-fold symmetry on tilt-c-plane sapphire substrates

[en] The parallel plate dielectric resonator was applied to surface resistance (R_s) measurement of high temperature superconducting films with small area for the purpose of material research in early stage. Using 38 GHz resonance of TE₀₁₃ mode, available measurement area in the film was diameter of 9 mm. From the theoretical calculation, the measurement at higher frequency had an advantage of less error in R_s that is caused by dielectric loss tangent (tanδ). The effect of dielectric loss is negligible at 38 GHz even using a sapphire with order of 10^-7 of tanδ. In lower R_s region, R_s values of YBa₂Cu₃O_y that were measured at 38 GHz agreed well with that of standard measurement method at 22 GHz. However the difference of R_s between two methods became larger with increase of R_s. It is owing to poor signal to noise ratio at higher frequency

No abstract available