Gelation of imidazolium ion-based ionic liquids takes place after being ground with single-walled carbon nanotubes. Transmission electron microscopy showed that heavily entangled nanotube bundles are untangled to give finer bundles during gelation. Differential scanning calorimetry, X-ray diffraction analyses, and rheological studies indicated that the gels are formed by physical crosslinking of the nanotube bundles, mediated by local molecular ordering of the ionic liquids, rather than by entanglement of the nanotubes. The use of polymerizable ionic liquids as the gelling media allowed the fabrication of polymer/nanotube composites that are mechanically reinforced and electrically conductive.

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Supramolecular complexes of calix [4] resorcarene (1: host molecule) with chiral polar molecules (guest molecules), such as carboxylic acids, alcohols, amino acids, and esters, were formed by solid-solid grinding more efficiently than the reaction of host and guest molecules in solution. When a guest molecule is chiral the complex exhibited circular dichroism (CD) Cotton effects reflecting the absolute configuration of the guest chirality. Thus the process of solid-state complexation followed by CD measurement is applicable to the assignment of absolute configuration for chiral guest molecules.

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We propose a new process of sol-gel casting. The process consists of the dispersion of fine crystalline particles in a sol-gel derived precursor solution followed by casting and annealing at relatively low temperatures. In this paper, we introduce the basic concepts for optimizing the process parameters. Dense ferroelectric PMN-PZT films with the thickness of 1μm were formed on a Si wafer by a single coating operation. The thick PMN-PZT film formed with the optimized process parameters showed a fairly good ferroelectricity with a good dielectric property.

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The present work studied the effectiveness of secondary flow injection into a cyclone on the separation performance of sub-micron particles. The particle collection efficiency increased with the secondary flowrate when injected in the upper cylindrical section of the cyclone. It was found that high particle collection efficiency is attained when the injection location of the secondary flow is close to the upper plate at a high flow velocity. A new type of cyclone developed based on these results achieved a high collection efficiency, which was in qualitative agreement with the three-dimensional simulation results.

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A dry mechanical processing device with glow discharge in milling machine was newly developed. Using the device, nanosized TiO₂ powder (301m²/g) was mechanically activated under glow discharge with NH₃ (10%)/Ar gas (300Pa). The resultant powder was pale yellow in color, and the specific surface area was 283m²/g. The processed powder had higher photocatalytic activity than the raw powder, when it was evaluated through the decomposition of acetaldehyde vapor under fluorescent lamp.

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Monodispersed nano-silica particles were continuously synthesized via the hydrolysis of tetraethyl-orthosilicate (TEOS) in a methanol solution with a small tube type reactor. The tube type reactor consists of a handmade T-type glass mixer and Tygon tube for aging. Reaction was initiated by mixing TEOS methanol solution with a mixture of methanol and ammonia water in the T-type mixer. The morphology of particles formed was dependent on the reaction temperature as well as the water concentration. Monodispersed silica nano-particles were synthesized by stöber method using a batch reactor, and they were compared in size with those formed by the tube type reactor. It was found that smaller silica nano-particles are obtained with increasing the reaction temperature and the water concentration. Especially with the tube reactor, the particle size depends mainly on TEOS concentration.

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Influences of mixing-grinding conditions on the properties of magnetite powders synthesized from the metallic-iron and hydrated iron [III] oxide powders in organic liquids containing hydrogen peroxide were investigated. The calcination products were characterized by X-ray diffractometry and ⁵⁷Mössbauer spectroscopy. The yield of magnetite increased with the milling time and revolution frequency. The synthesis of magnetite powder was almost complete at 300rpm for 5 hours. After calcination at 773K in Ar, calcination product γ-(Fe^III)_A(Fe^II_0.58^III_1.28)_BO₄, was highly non-stoichiometric compound. The degree of non-stoichiometry increased with the yield of magnetite. For the calcinations in Ar, the degree of non-stoichiometry decreased by the reaction with residual iron. The addition of H₂O₂ suppressed the reaction of Fe and FeO(OH) to form magnetite.

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The color of inorganic pigment consists of the reflecting and permeating lights. The reflectance of inorganic pigment is dependent upon both primary and agglomerated particle size and shape. As for the iron oxide pigment with red tone color, the tone color changed systematically from yellowish red to red, dark red, dark purple and black, with increasing the particle size and changing the particle shape. The permeating color of the pigment is determined by atomic position and electron state. Molecular orbital calculation could simulate the color of permeating light.

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