Kenji Hisada

Hydrogen evolution sensitized by tin-porphyrin in microheterogeneous systems

A novel, photoinduced hydrogen evolution system involving tin-porphyrin was studied in three microheterogeneous systems namely nonionic, anionic and cationic. It was found that by using nonionic surfactant the system could reduce water to evolve hydrogen efficiently compared to the ionic surfactant system. It was also confirmed that hydrogen evolution in the micelle system depended strongly on the type of micelle used; a possible mechanism for this phenomenon is suggested.

Microscopic friction anisotropy and asymmetry related to the molecular tilt azimuth in a monolayer of glycerol ester

Abstract The molecular tilt azimuth in domains of a condensed phase in monolayers of 1-monopalmitoyl- rac -glycerol and 1-monostearoyl- rac -glycerol at the air/water interface exhibits a regular star texture. Lateral-force microscopy has been used to investigate the friction behavior of these monolayers that have been transferred onto silicon substrates. The condensed domains revealed strong friction anisotropies and asymmetries. The angular dependence of these properties correlates well with the tilt azimuth of the alkyl tails in the monolayer.

Evaluation of disperse dye sublimation via gas chromatography

Abstract Gas chromatography has been examined as a method for characterising the sublimation property of disperse dyes. In this regard, the vapor pressure of azo and anthraquinone dyes were recorded and the Arrhenius plots utilising the experimental vapor pressures formed straight lines. Heats of sublimation (Δ H sub ) and heats of vaporization (Δ H vap ) were calculated using experimental data from GC measurements and were compared with Δ H sub and Δ H vap values obtained from previous methods. The results indicate that vapor pressure values arising from the GC method were only slightly different from the values measured by the Knudsen effusion and transpiration methods. It is believed that the observed differences are due to irregularities in the crystalline state of dyes in the methods employed.

Triplet excimer formation in Langmuir-Blodgett polymer films of poly[2-(9-carbazolyl)ethyl methacrylate-co-isobutyl methacrylate]

Abstract The triplet state behavior of carbazole-containing polymer Langmuir-Blodgett films was investigated. The carbazole groups are localized at the hydrophobic part of the layered film and form a triplet excimer which is attributed to interlayer interaction at the interfaces between layers. The degree of interaction between carbazole chromophores in the triplet state is determined by the interchromophore distance.

A rotaxane synthesis based on stilbene photoisomerization. A photoswitchable catch and release process.

A [2]rotaxane, having (Z)-alpha-methylstilbene as a stopper, is (1) synthesized in good yield by using a (E)- to (Z)-stilbene photoisomerization process, and (2) dissociated by reverse photoisomerization from (Z)- to (E)-stilbene.