Reaction of an activated carbon with hydrogen atoms was carried out using a microwave discharge flow apparatus to elucidate the conditions under which carbonaceous material such as carbon deposit on the catalyst was efficiently gasified by the interaction with atomic hydrogen. Hydrocarbons mainly consisted of methane were produced steadily. DRIFTS spectra and pyridine extraction of the activated carbon after the reaction with hydrogen atoms showed that functional groups due to partially hydrogenated moieties were not formed on the surface of the activated carbon during the irradiation of atomic hydrogen.
Regeneration of coked Ni/SiO₂ catalyst induced by atomic hydrogen was investigated through the catalytic reaction of CO/H₂ mixture. The catalytic activity and selectivity of the coked catalyst were substantially regenerated by the treatment of hydrogen atoms at 573 K, under 279 Pa for less than 1 h. In contrast, regeneration could not be achieved by the treatment of H₂ at the same temperature. A plausible scheme for the reaction of carbonaceous materials deposited on the catalyst with atomic hydrogen was qualitatively discussed.

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Japanese cedar bark was pyrolyzed at 473-1273 K under atmospheric pressure in a flow of nitrogen. Morphology, adsorption properties, and surface properties of the products were examined to characterize the pyrolyzed cedar bark. Although elongated tubular cells and fibrous materials in the bark shrank during the heat treatment, features of fibrous cedar bark were macroscopically preserved in the samples pyrolyzed even at higher temperatures without significant decay of the morphology. The development of microporosity was observed for the samples pyrolyzed at 773 K and higher temperatures; S_BET (specific surface area) 80-448 m²g^-1, V_p, (pore volume) 0.07-0.21 mLg^-1, and D_p, (mean pore diameter) 0.46-0.77 nm. α_s-plot indicated that surface properties of cedar bark pyrolyzed at 1073-1273 K were similar to those of carbon black, whereas those of samples pyrolyzed at 873 K and lower temperatures were different from them. Diffuse reflectance FT-IR spectra showed that functional groups such as substituted aromatic rings and ether groups were present on the surface of the samples pyrolyzed below 873 K, which would have effects on the surface properties of the resultant material

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Fluorogenic host capped regioselectively at the lower rim, 2^A, 2^x-disulfonyl dibenzosulfolane-diphenyl capped β-cyclodextrin (X = D for β-1) and γ-cyclodextrins (X = C, D and E for γ-1, γ-2 and γ-3), respectively, have been investigated their fluorescent molecular sensing properties for endocrine disruptors in an aqueous solution. These capping cyclodextrins exhibited monomer fluorescence, in which these hosts fluorescence decreased in intensity on accommodation of endocrine disruptors. The extent of fluorescence variation with a guest was employed to evaluate the sensing abilities of the hosts, using the parameter (ΔI/I⁰) as a sensing factor of the hosts for the guests. Hosts β-1, γ-2 and γ-3 detected phenolic guests such as 3, 4-dichlorophenol, 2, 4, 6-trichlorophenol, p-nonylphenol, and bisphenol A with high sensitivities, and especially, these three hosts exhibited the highest sensitivities for bisphenol A. The sequences of binding of the hosts were γ-3>β-1>γ-2>γ-1 for 3, 4-dichlorophenol and 2, 4, 6-trichlorophenol and β-1>γ-3>γ-2>γ-1 for p-nonylphenol and bisphenol A. The behaviors of the capped units of the hosts during a host-guest complexation were studied by fluorescence spectra and MM2-energy minimized structures. These studies suggest that the capping linker units, which are disulfonyl dibenzosulfolane-diphenyl, work as qualitatively fluorescent probe detecting endocrine disruptors.

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The transient response of the transversal effects of a piezoceramic transducer is introduced in measurements of the viscosity of liquids. Viscosities of water-glycerin mixtures and silicone oil were measured from the motional current of transducer at a resonant frequency of 23 kHz and its higher harmonic frequencies of 68, 110 kHz, respectively.

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Wasted tungsten scraps are important resources for recycling, however, the mechanical recycle process of tungsten has a difficulty for recycling due to its mechanical strength. Underwater explosion fracturing technique was designed for solving this problem. The kinetics for alkaline leaching of roasted tungsten alloy scraps with different size distribution prepared by two ways of crushing technique has been investigated to evaluate the effect of the underwater explosion-crushing. The merit of this technique for fracturing of waste tungsten alloy scraps can be understood by estimating of those leaching tendencies. The present work aims at the evaluation of the explosion-crushing method for efficiency of alkaline leaching from a kinetic point of view. Alkaline leaching was carried out with 10% NaOH solution in the range of 293-353K at various times. The leaching of roasted tungsten carbide scraps by NaOH was strongly dependent on temperature and leaching time, and underwater explosion accelerated the leaching ratio. The leaching mechanism was turned out to reaction controlled, and activation energy of alkaline leaching was 60-64 kJ/mol.

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