Kiyoshi Kanie

Ellipsoidal anatase TiO2 nanoparticles of different aspect ratios were obtained by the gel-sol method in the presence of amino acids in which the resulting particles were basically single crystals, but highly rough surfaces or partly polycrystalline structures were observed with a high concentration of glutamic acid or aspartic acid.

Folic acid derivatives having 2-(3,4-dialkoxyphenyl)ethyl moieties have been found to exhibit thermotropic liquid-crystalline behavior. Smectic and discotic phases are observed for these compounds over wide temperature ranges. X-Ray diffraction and infrared measurements show that the formation of the smectic and discotic phases is due to the ribbon- and disk-like structures of the pterin rings of folic acid, respectively. The smectic phase is changed to a hexagonal columnar phase by the addition

A novel organic-inorganic hybrid thermotropic liquid crystal (LC) is developed by the hybridization of an organic amine with a mesogenic core and an acicular anisotropic TiO2 particle through the adsorption of the amino group to the surfaces of the TiO2. The hybrid LC shows nematic phases in wide ranges of temperatures. Variable-temperature small-angle X-ray measurements reveal that the formation of the one-dimensional nematic order of the acicular particles on a submicrometer scale induces ther

The first simple-cubic liquid crystal was obtained by coating monodisperse Au nanoparticles (NPs) with a thick corona of amino-substituted organic dendrons. This unusual structure was determined by grazing-incidence diffraction and electron density reconstruction and explained by analyzing the radial density profile of the corona. Another novel structure is proposed for the phase preceding the cubic one: a hexagonal superlattice composed of alternating dense and sparse strings of Au NPs.

Abstract Trifluoromethyl ethers R-OCF3 are easily synthesized from the corresponding dithiocarbonates R-OCS2Me (R = aryl or primary alkyl) by a reagent system consisting of 70% HF/pyridine and an N-halo imide. When the reaction is applied to R-OCS2Me wherein R = secondary alkyl, tertiary alkyl, or benzylic group, fluorination leading to the corresponding alkyl fluorides R-F is achieved, whereas a combination of 50% HF/pyridine and N-bromosuccinimide affords the corresponding trifluoromethyl ethe

A novel organic-inorganic hybrid thermotropic liquid crystal (LC) is developed by the hybridization of an organic phosphate having a mesogenic core and monodispersed alpha-Fe2O3 particles with different shapes through the specific adsorption of the phosphate group to the surfaces parallel to the c-axis of the alpha-Fe2O3. The hybrid LC shows thermotropic nematic or cubic liquid-crystallinity in wide ranges of temperatures. Variable-temperature small-angle X-ray measurements reveal that the spont

Abstract Trifluoromethylamines are easily synthesized from dithiocarbamates by a reagent system consisting of tetrabutylammonium dihydrogentrifluoride and an N-halo imide under mild conditions. When this reaction was applied to dithiocarbamates ArN(R)CS2Me at higher temperatures, the trifluoromethylation was accompanied by halogen substitution at the p-position of the Ar group. The synthesis of trifluoromethyl-substituted adenosine is also described.

Calcium titanate fine particles controlled precisely in size and morphology were synthesized by an optimized hydrothermal method. Their photocatalytic activity was evaluated as the effect of the particle morphology, that is, the exposed surface. The size and morphology were successfully controlled with aging temperature and alternative use of Ti-sources, such as a TiO2 dispersion and titanium–triethanolamine complex. The photocatalytic activity of the CaTiO3 fine particles was measured by the ev

Thermotropic discotic and smectic liquid crystallinity can be induced for folic acid derivatives having octadecyl and undecyl substituents in wide temperatures ranges, respectively; the addition of sodium triflate to smectic liquid-crystalline folic acid leads to a change of the assembled structures from smectic to columnar phases.

Monodispersed barium zirconate fine particles with high crystallinity were synthesized by hydrothermal reactions using barium hydroxide and a Zr–triethanolamine complex.

The reagent consisting of 70% HF–py (py = pyridine) and a halonium oxidant converts R–OCS 2 Me into either R–OCF 3 (R = primary) or R–F (R = secondary, tertiary or benzylic) whereas the 50% HF–py system converts R–OCS 2 Me (R = secondary) into R–OCF 3 .

Abstract Lipophilic folic acid derivatives exhibit lyotropic liquid-crystalline states in organic solvents. The change of the mesophases from lamellar to columnar is induced by the change of specific hydrogen bonding patterns from ribbon to disk with the increase of hydrophobic environment.

This study is focused on surface-modified Fe₃O₄@SiO₂ particles with precisely controlled sizes and shapes applied in magnetorheological (MR) fluids. After the preparation of the monodisperse spindle-shaped and cubic Fe₃O₄@SiO₂ particles, surface modification with dodecyltrimethoxysilane (DTM) was carried out <i>via</i> a silane coupling reaction to increase the dispersion stability of the particles. Afterward, MR fluids were prepa

Cubic-shaped Bi0.5Na0.5TiO3 (BNT) and Bi0.5K0.5TiO3 (BKT) fine particles with narrow size distribution were directly prepared as a single phase from a suspension of TiO2 anatase nanoparticles mixed with Bi(OH)3 in aqueous alkaline metal hydroxides solutions by highly condensed hydrothermal method at 200–250°C for several hours. It was investigated that the effect of particle mean size on the piezoelectric properties of thus obtained BNT and BKT fine particles.