[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] The free energies, enthalpies, and entropies of complexation of lanthanide ions by benzene-1,2-dioxydiacetate have been determined by potentiometry, calorimetry, and solvent extraction. Comparison of the entropy values with those of analogous complexes involving bi-, tri-, and tetradentate diacetate ligands gives an entropy change of ca. 95 +- 10kJK^-1 mol^-1 per carboxylate group. This correlation was used to obtain a relative measure of the Lewis basicity of the other ligand donor sites (oxo, imino, thio). The lanthanide cations do not interact with the thio donors while the order with the oxo and imino donors is (-CH₂NCH₂CO₂^-)₂ greater than N(CH₂CO₂^-)₂ equal to or greater than 0(CH₂CO₂^-)₂ greater than (-CH₂OCH₂CO₂^-)₂ greater than Ph(OCH₂CO₂^-)₂

No abstract available

[en] The Fermi surface instability in quasi-two-dimensional electrons is investigated as a possible model of oxides superconductors, (La/sub 1-x/M/sub x/)₂CuO/sub 4-δ/. The spin density wave (SDW) transition temperature within the mean field approximation is obtained as a function of band filling. It is found that SDW is stable only in a small region around the half filling of the band

[en] This paper discusses the relationships between concepts of the core support system, fuel handling system and reactor shutdown system, which poses major problems in the design of the reactor internals for future LMFBRs. Designers of the LMFBR reactor internals will be forced to solve the structural materials problems which are caused by the fast neutron irradiation. The enhanced bowing of the core component ducts due to radiation-induced swelling has posed difficult problems in the core restraint design. Three types of core restraint systems - the active, passive and the static systems -were compared with each other along with such additional considerations as the acceptable load capacity of IVHM, the alignment of the absorber assembly channels and the controlling reactivity and the maintainability of the structure elements of the active system. The fluence limit requirements on core support structures to minimize the irradiation-induced degradation of the mechanical properties of the structural materials demanded the choice of the design concept which incorporates replaceability of any structure elements essential to safety in order to avoid longer fuel assembly features caused by the provision of considerably thick shielding region. But this option brought the restriction in available in-vessel fuel handling systems. The conceptual studies of absorber assemblies and drive mechanisms, especially scram assisting methods, for the primary and the secondary shutdown systems have also been conducted by taking account of such effects on scram times as bowing of the individual control duct assemblies, displacements caused by core deflection and earthquakes. (author)

[en] New trivalent ion conducting solid electrolytes with NASICON type structure, [(Ce_1-xLa_x)_0.1Zr_0.9]_40/39Nb(PO₄)₃, were successfully developed and their ion conducting behaviors were investigated. Among the [(Ce_1-xLa_x)_0.1Zr_0.9]_40/39Nb(PO₄)₃ series prepared, the highest ion conductivity was obtained for [(Ce_1-xLa_x)_0.1Zr_0.9]_40/39Nb(PO₄)₃ (x=0.8). The trivalent ion conductivity was approximately four times higher than that of cerium (Ce³⁺) ion conducting (Ce_0.1Zr_0.9)_40/39Nb(PO₄)₃, and the values exceeded the region of the representative divalent oxide anion conductors such as yttria stabilized zirconia (YSZ) and calcia stabilized zirconia (CSZ) at temperatures below 500 deg. C

No abstract available

[en] Possible types of superconductivity in both quasi-one- and quasi-two-dimensional systems are examined theoretically. The NMR relaxation rate, T₁^-1, is calculated for each state. The comparison with the experiment in (TMTSF)₂ClO₄, which is the quasi-one-dimensional organic superconductor, indicates that the superconductivity of this family has lines of zeros of the gap on the Fermi surface. It is suggested that β-(BEDT-TTF)₂X can be in the triplet state

[en] We have searched for signatures of polarization of partons in hadronic jets from Z⁰→qq decays using the 'jet handedness' method. We find no evidence for jet handedness in a sample of light quark jets. We set an upper limit of 9.1% on magnitude of the analyzing power of this technique at the 95%C.L. We have studied an alternative definition of jet handedness and found no signal. ((orig.))

[en] Off-diagonal geometric phases acquired by an evolution of a 1/2 -spin system have been observed by means of a polarized neutron interferometer. We have successfully measured the off-diagonal phase for noncyclic evolutions even when the diagonal geometric phase is undefined. Our data confirm theoretical predictions and the results illustrate the significance of the off-diagonal phase