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Organic solar cells based on copper naphthalocyanine (CuNc) and fullerene (C 60 ) were fabricated, and their photovoltaic properties were investigated. C 60 and CuNc were used as n-type and p-type semiconductors, respectively. In addition, the effect of Au nanoparticle addition on a hole transfer layer was investigated, and the power conversion efficiency of the devices was improved after blending the Au nanoparticles into the hole transport layer. Nanostructures of Au nanoparticles were investigated by transmission electron microscopy and X-ray diffraction. Energy levels of molecules were calculated by molecular orbital calculations, and the nanostructure and electronic properties were discussed.

Nanodiamond-based solar cells were fabricated and the photovoltaic properties were investigated. Fullerene (C 60 ) and fullerenol (C 60 (OH) 10–12 ) were used as n-type semiconductors, and diamond nanoparticles and metal phthalocyanine derivative were used as p-type semiconductors. The nanostructures of the solar cells were investigated by transmission electron microscopy and X-ray diffracometry, and the electronic property was discussed.

Fullerene-based bulk heterojunction solar cells were fabricated, and the electronic and optical properties were investigated. C 60 were used as n-type semiconductors, and porphyrin, CuInS 2 and diamond were used as p-type semiconductors. An effect of exciton-diffusion blocking layer of perylene derivative on the solar cells between active layer and metal layer was also investigated. Optimized structures with the exciton-diffusion blocking layer improved conversion efficiencies. Electronic structures of the molecules were investigated by molecular orbital calculation, and energy levels of the solar cells were discussed. Nanostructures of the solar cells were investigated by transmission electron microscopy, electron diffraction and X-ray diffraction, which indicated formation of mixed nanocrystals.

Diamond:fullerene nanocomposite thin films were fabricated, and the photovoltaic properties were investigated. C60 and diamond were used as n-type and p-type semiconductors, respectively, and the nanostructures of the thin films were investigated by transmission electron microscopy and X-ray diffraction. Energy levels of the clusters were calculated by molecular orbital calculations, and the nanostructure and electronic property were discussed.

The carburizing time is expected to be short at high temperatures, where grains of the dual-phase steel are fine and hardly grow. If it can be used for the elevated temperature case hardening steel, the processing time might become short by reducing carburizing time and by skipping the first step quenching for grain refinement of the un-carburized core. In the present study, the applicability of the dual-phase steel for the elevated temperature case hardening steel has been investigated.The 2.0 mass% Si-(0.01-0.08) mass% C-(0.1 mass% V, 0.05 mass% Nb and 0.05 mass% Ti) steel were carburized at 1323 K for 10.8 ks, quenched from various temperatures and then tempered at 423 K. The microstructural observation, hardness measurement and tensile test of the core were carried out. When the microstructure was controlled to be dual-phase with α+γ at the carburizing temperature, the grains were fine and no grain growth was observed during the carburizing process. Therefore, the first step quenching for grain refinement might be skipped. The core showed the excellent strength-ductility combination compared with the conventional case hardening steel. The distribution of hardness in the carburized layer showed a gentle gradient due to the elevated temperature carburizing. The carburizing time was reduced to be 1/ 3 compared with the conventional carburizing. The grains in the carburized layer were also refined by additions of V, Nb and Ti.

C60-based bulk heterojunction solar cells were fabricated, and the electronic and optical properties were investigated. C60 were used as n-type semiconductors, and copper oxides, CuInS2 and diamond were used as p-type semiconductors. Electronic structures of the molecules were investigated by molecular orbital calculation, and energy levels of the solar cells were discussed. Nanostructures of the solar cells were investigated by transmission electron microscopy, electron diffraction and X-ray diffraction, which indicated formation of mixed nanocrystals.

The dilute Cu-Nb-Sn alloys containing small amounts of Nb and Sn less than 1 at % exhibited superconductivity after quenching from the liquid state and ageing. The best superconducting properties (\(T_{{\text{c}}_2 } \) andJc=130 A cm−2) in a Cu-0.30 at % Nb 0.15 at % Sn alloy were obtained when the sample was aged at 550° C for 384 h. This sample exhibited a structure of fine Nb3Sn precipitates of 200 to 500A diameter distributed homogeneously in the Cu matrix, and therefore it was concluded that superconductivity in these alloys resulted from the proximity effect of Nb3Sn particles. In spite of the similar structure obtained by ageing at 800° C, the Cu-Nb-Sn alloys showed inferior superconducting properties compared to the Cu-0.4 at % Nb alloy and this would be explained qualitatively by the difference in the mean free path in the two alloys.

A tetratetracontapeptide amide corresponding to the entire amino acid sequence of porcine hypothalamic growth hormone releasing factor (pGRF) was synthesized by a conventional solution method, by assembling nine peptide fragments followed by deprotection with 1 M trifluoromethanesulfonic acid-thioanisole in trifluoroacetic acid. The synthetic peptide was as active as synthetic human GRF-44-NH2 in an in vitro assay. A new substituted hydrazine, 2, 2, 2-trichloro-tert-butoxycarbonyl hydrazine, was employd for the preparation of a hydrazide containing Glu(OBzl). In the deprotecting step, Me2Se was empliyed to facilitate acidolytic cleavage of protecting groups, as well as reduction of Met(O).

An investigation was made on the strain dependence of critical cuurent Ic for three kinds of practical Nb3Sn superconducting wires which are in the course of development, with an emphasis on the correlation with wire constitution.In the internal tin diffusion processed wires with a single tin core at the center, the reversible strain limit, eirrev was small and the strain sensitivity of Ic was high. This is ascribed to the strain concentration induced by Kirkendall voids observed in the center of fracture surface.Internal reinforcement using SUS 405 steel increased both em, the strain corresponding to peak Ic, and the strain sensitivity, and decreased the eirrev in addition to a marked increase of flow stress. In the light of both the serration in the stress-strain relation and fracture surface morphology, the degradation of strain characteristics are attributable to the strain concentration in Nb3Sn layer associated with localized deformation of the steel at low temperatures.In the external tin diffusion in situ processed wires, both Nb3Sn layer formed in the periphery and the unreacted core in the center of the wire controlled the strain characteristics. The smaller the core size was, the larger the critical current density and the smaller the em or eirrev. Inhomogeneity of tin diffusion in the cross section as well as in the longitudinal direction resulted in deviation of the core and tin balling, respectively. They deteriorated the strain characteristics of the wire significantly.Improvements of the strain characteristics in these wires through proper constitution and heat treatment were briefly discussed.

Microstructures in a commercial Nb-Ti alloy heat-treated or repeatedly aged and cold worked have been investigated by transmission electron microscopy. In the aged samples after solution treatment,ω-phase forms at ageing temperatures below 673 K andα-phase precipitates at 773 K. Cold work after solution treatment or heavy cold work without prior solution treatment results in accelerated precipitation ofω-phase on ageing at 623 K and ofα-phase on ageing at 773 K, while it givesα-precipitation instead ofω on ageing at 673 K. Repeated ageing and cold work make the microstructures very fine. The refinement is due to formation of dislocation cell structures and subgrains and precipitation ofω- andα-phases.

Etude des ameliorations des proprietes en champ intense des supraconducteurs par addition de 2% Zr, 2% Hf et 2% Ta a Cu-20% masse Nb liquide. Observation des structures eutectiques autour des dendrites de Nb. Mesure des densites de courant critique jusqu'a 15 T apres differents traitements thermiques

Al-Fe, Al-Sn, Al-Cu, Al-Zn and Al-Zr binary alloys of various concentrations were rapidly solidified from melt into foil form. The microstructures of these alloys were studied with respect to the origin and arrangement of dislocations.Cell boundaries could be classified into three types with respect to the dislocation arrangement as reported in our previous work4); and a new type was found in Al-Sn alloys.The origin of dislocations could be explained by the theory that it would be resulted from the constitutional stress on the cell boundaries due to solute segregation. Consequently, the highest dislocation density was found in the alloys, where the difference of atomic radii between solvent and solute atoms was great and the difference of solute concentrations between on the boundary and in the interior of cells was also great. The second mechanism for the origin of dislocations would be prismatic punching, which was observed at large secondary phase particles.

High purity aluminum and binary alloys of Al-Mg, Al-Zn, Al-Mn, Al-Si and Al-Fe of various solute-concentrations (contents of the other metals in Al) were solidified rapidly and uni-directionally. Their microstructures were studied with respect to the origin and arrangement of dislocations.The arrangement of dislocations was different from that of the foilcast specimens previously reported. Dislocations were rarely arranged along the cell boundaries where solute segregations were high. It would be explained that the origin of dislocations resulted from the constitutional stress on the cell boundaries due to the solute segregations as in the foilcast specimens. However, many dislocations in the bulk-specimens rapidly solidified would also be generated by the thermal stress.Subboundary structures were more frequently observed with the increase in solute concentrations. They consisted of relatively regular networks of dislocations in Al-Mg and Al-Mn alloys, and of complicatedly tangled disocations in Al-Zn and Al-Si alloys.

A 44 residue peptide amide corresponding to the entire amino acid sequence of bovine hypothalamic growth hormone releasing factor (bGRF) was synthesized by assembling nine peptide fragments via the azide followed by deprotection with 1M trifluoromethanesulfonic acid-thioanisole in trifluoroacetic acid. Met(O) was reduced by dimethylselenide during the above acid treatment. The synthetic peptide was as active as synthetic human GRF-44-NH2 in vitro assay.

It has been reported that N-(α-methylbenzyl) linoleamide (MBLA) had a remarkable cholesterol-lowering effect on the experimental hypercholesterolemia in rabbits and rats.There are three optical isomers of MBLA: D-, L- and DL-MBLA because of an asymmetric carbon atom in the amine moiety of MBLA. And the potency of the cholesterol-lowering effect was found to be the following order: D->DL->L-MBLA.Fukushima also found that the respiratory excretion of 14C after oral administration of carboxy 14C-labeled L-MBLA to rats was significantly greater than that of D- or DL-MBLA, whereas the ratio of urinary 14C excretion of D-MBLA was higher than that of L- or DL-MBLA. These results suggest that the difference of the cholesterol-lowering potency observed among the MBLA isomers might be closely related with the difference of biological disposition of the isomers.The present paper describes the results of in vitro studies on the enzymatic hydrolysis of the amide linkage of MBLA isomers.