Structural effect and oxygen storage capacity (OSC) on alumina-supported cerium oxide catalysts have been studied. The behavior and activity of active oxygen species originated from OSC also have been characterized. In those catalysts, the catalyst prepared by an alkoxide method using needle boehmite sol derived from aluminum tri-isopropoxide (AIP) and cerium nitrate dissolved in ethylene glycol gave a finely-divided nonstoichiometric cerium oxide dispersed on alumina (Ce0_2-x/Al₂O₃) after the H₂reduction at 900°C. The presence of a finely-divided nonstoichiometric cerium oxide containing Ce₃₊and Ce₄₊ ions was anticipated by XRD, EXAFS and fluorescent measurements. The higher OSC was achieved on Ce0_2-x/Al₂O₃ catalyst, compared with CeO₂/Al₂03 and CeAlO₃/Al₂O₃ where cerium oxides were stoichiometric structures. It was concluded by ₁₈O tracer studies that the higher activity of Ce0_2-x /Al₂O₃ catalyst for methane oxidation was mainly associated with the activation sites of oxygen species, where the sites consisted of oxygen vacancies formed by finely-divided nonstoichiometric structures, from the surface to the bulk and vice versa. The addition of palladium to CeO₂/Al₂O₃ catalyst enhanced drastically the OSC and improved the catalytic activity on NO decomposition by the acceleration of oxygen spillover, indicating the generation of synergetic effect between Pd and CeO_2-x. The good relation between OSC and NO decomposition activity on Pd/CeO_2-x, /Al₂O₃ catalyst might promise the preparation of new catalyst by the control of OSC.

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The sonochemical reaction of argon-dissolved formic acid-water solution was carried out. The main gaseous products were CO, CO₂ and H₂. It was interesting that CO was obtained by sonolysis of formic acid. In the cases of degassed or CO₂-dissolved sample, only a little product was detected. The reactivity depended on the dissolved gases. For example, the amounts of CO and H₂ decreased for the air-saturated sample. Thus, dissolved gases play an important role in the sonolysis. Effects of formic acid concentration and temperature on the reactivity were also examined. Not only the amounts of gaseous products for 1h but also the ratio of CO to the other products reached the maximum value at 1:1 solution. Temperature dependence of the gas evolution rate was observed in the rage of 5-45°C. It was found that the temperature dependence was affected by formic acid concentration. In the case of low concentration (5 %), temperature dependence was clear; i. e. the rate of CO production decreased with increase of temperature.

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New imidazoles-cobalt (II) acetate complexes and their polynuclear complexes were synthesized by the reaction of cobalt ( II) acetate with imidazoles (HL: HIm, 2-CH₃. HIm, 2-C₂H₅ HIm, 2- (CH₃) 2CH H Im, 4-CH₃ HIm). The mononuclear complexes obtained were [CoA₂(HL)₂] (A: C H₃C00-)with the tetrahedral configuration, and no complexes of [Co (HL), ₂]A₂( n =4, 6) type could be synthesized. Pink polynuclear complexes in the form of [CoL₂]. (L: i m-, 2-CH₃ - im-, 2-C₂H₅i m -, 4-CH₃im-) with the tetrahedral cobalt (II) units were obtained by reftuxing a ethanol, 1-propano l or 1butanol solution of [CoA₂ (HL) ₂], whereas [Co (2- (CH₃) ₂CH im) ₂]n did not yield. Thermal properties of [CoA₂ (HL) ₂] and [CoL₂], were also investigated.

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Complex formation (1:1) between M (M = Cu, Zn, Mn) and 2- (5-bromo-2-pyridylazo) -5- (NpropylN-3-sulfopropylamino) phenol (5-Br-PAPS) has been studied by spectrophotometry at 25°C and at 1= 0.1 (NaNO₃). The protonated complex, MHL, is found to exist in equilibrium with the normal complex, ML, at pH 1-2 for Cu (II) and pH 4-5 for Zn(II). The ML complex is only formed for Mn(II)at pH > 6.5. The formation constants KMLa nd ICMHaLr e obtained by a graphical analysis. Comparison of the KML values obtained with those for the complexes having similar structure showed that the stability of the ML complexes is governed by the basicity of the oxygen atom ortho to the azo group but not affected by the other substituent in the para or meta position. The values of Kmm, obtained are found to be much smaller than those of the PAR complexes.

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Concentrations of halide ions of river waters in the Kusatsu-Shirane volcano area, Gunma, were measured by ion chromatography. The decreasing order of concentration among halide ions at various sampling locations is in general; chloride ion > fluoride ion > bromide ion > iodide ion. A strong correlation was observed between the concentrations of the chloride and bromide ions. High halide ion concentrations were observed in river waters indicating that the volcanic activity of Mt. Kusatsu-Shirane is the major source of halide ions in river waters of the area. Measurements of halide ion concentrations along the downward streams of selected rivers revealed that concentration ratios among halide ions were not varied substantially in the absence of any circumstantial change. The amounts of halide ions transported from the Kusatsu-Shirane volcano area by rivers per year were estimated to be 1.4 ×10⁷ mol for the fluoride ion, 3.8 × 10⁸ mol for the chloride ion, 4.1 × 10⁵ mol for the bromide ion and 1.0 × 10⁵ mol for the iodide ion.

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Optical resolution was accomplished by HPLC on a column packed with an ion exchange adduct of spherical clay and an optically active metal complex [δ -tris (1, 10-phenanthroline) ruthenium ( II ) ]. Sixty-four chiral compounds out of 112 tested were optically separated with high resolution by using the column (RU-1) under several conditions. This chiral column is expected to be widely applicable to various samples for optical resolution.
We prepared a column (R U-N) packed with an ion-exchange adduct of cation exchange packing materials (Nucleosil 100-5SA, Macherey Nagel Co. ) and the optically active metal complex. RU-N was used to separate enantiomers of only 1, 1'-bi-2-naphthol. The gap between RU-1 and RU-N had been studied. Retention behaviors of polyaromatic hydrocarbons on those columns indicate that the stationary phase of RU-1 has strong 7r-electron interaction with these compounds but that of RU-N was weak. Retention behaviors of triphenylene (a planar molecule) and o-terphenyl (a nonplanar molecule) on those columns indicate the planar recognization of RU-1 was superior to that of RU-N. These were considered to arise from structural specificity of the optically active metal complex between the clay sheets.

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When a benzene solution (20 mL) of azoxybenzene (1) (0.51 mmol) was irradiated with UV rays in the presence of trichloroacetic acid (5.0 mmol), a higher yield of 2-hydroxyazobenzene (2) was obtained compared with yield in the absence of trichloroacetic acid.
A compound 4-methyl-ONN-azoxybenzene (6α) in benzene isomerized to 4-methyl-NNO-azoxybenzene (6β) upon UV irradiation. On the other hand, 6β did not isomerize at all to 6α under the same reaction conditions. A rearrangement product 2-hydroxy-4'-methylazobenzene (7) seems to be derived from 6β through an intramolecular pathway.
The two starting materials 6α and 6β are interconversible upon UV irradiation in the presence of trichloroacetic acid.

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The reaction of 1, 1-diethoxy or 1, 1-diisopropoxy-2, 5-dipheny1-1-sila-3-cyclopentene, containing cis and trans isomers, with LDA f ollowed by t he reaction with alkyl b romides (alky1=Et, n-Pr, i-Pr, iBu, s-Bu) and then acetic acid was investigated. The cis isomer of the 2, 5-diphenyl-1-sila-3-cyclopentene was selectively substituted by alkyl group to give 1, 1-dialkoxy-r-2-alkyl-2, t-5-diphenyl-1-sila3-cyclopentenes. The trans isomer of 2, 5-dipheny1-1-sila-3-cyclopentenes could be isolated by silica gel chromatography from the reaction mixture.

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Since the discontinuance of production of specific fluorocarbons, 1, 1, 1-trichloroethane and so forth in 1995, many water soluble detergents such as ethylene glycol are used as substitutes. For recycling of a waste cleaning water containing ethylene glycol or some surface-active agents, waste water is ozonized together with ultraviolet (UV) radiation and hydrogen peroxide oxidation. Oxidized solution is passed through an activated carbon column, a cation exchange column and then an anion exchange column. The advantage of this oxidation process is no production of salts which should be removed when the cleaning water is reuse. By the ozonization combined with UV radiation and hydrogen peroxide oxidation, organic substances were oxidized with high efficiency.
Treated water by activated carbon can be reused as water to dissolve cleaning chemicals. The electric conductivity of the effluent from the anion exchange column was smaller than 20μS/cm. This effluent can be used as rinsing water at the final rinsing process.
On the basis of the present experimental results, we derived a practical recycling system of cleaning water. This recycling technique has enabled the reuse of waste water as detergents dissolving water or final rinsing water without water discharge.

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The titanium dioxide was prepared from the heat treatment of titanium from room temperature up to different temperatures of 600-900°C in an electric furnace and its photoelectrochemical characteristic was checked by the measurement of photocurrent, carrier density and quantum efficiency based on the photothermal method. The titanium dioxide thus prepared showed a lower carrier density with rise in heat treatment temperature and did not show clear dependence of flatband potential on heat treatment temperature. The heat treatment from room temperature up to ca.800°C provided the titanium dioxide with rutile structure which showed a maximum photocurrent, carrier density of 1-2×10¹⁷ cm^-3 and quantum efficiency over 50%.

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Reductive dehalogenation of 2, 4-dichloro-2, 4-dicyano-pentane using zinc together with viologens as an electron transfer catalyst under mild conditions produced cis- and trans-1, 2-dicyano-1, 2-dimethylcyclopropane (cis: trans=84: 16) in 91% yield. The reactions of 1, 3-dibromo-1, 3-diphenylpropane and 1, 3-dichloro-1, 3-diphenylpropane under the same conditions produced the 1, 2-diphenylcyclopropane in a good yield. The reaction was assumed to proceed via two electrons transfer from zinc to the dihalides and subsequent dehalogenation.

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