Surface structure of fine colloidal particles in aquous systems was quantitatively investigated using a small angle X-ray scattering method. The fine particles studied are micelles of N^a, N^a-dimethyl-N^E-lauroyllysine (DMLL, amphoteric surfactant) and octa(oxyethylene)monododecylether (C, , EB, nonionic surfactant), a small vesicle of didodecyldimethylammonium, bromide (DMA, cationic surfactant) and a globular protein molecule of ovalbumin (QA).
The scattering intensity I changes according to I=K₁q^-4+K₂ in a relatively wi de angle region. Here q is the wave vector and K₁, K₂ are constnats. This means that the electron density transition at the interface between the particles and the medium is relatively sharp. The surface roughness defined by the ratio of Os/Oso, where Os and Oso are the specific inner surface of the colloidal particle and a completely smooth sphere, are ca.3.5 for the DM LL micelle, ca.2 for the C₁₂ E₈ micelle, ca.1.7 for the OA molecule and ca.5 for the DMA vesicle.

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Over the catalyst containing (VO)₂P₂0₇ and -V0PO₄, C₃H₈ was oxidized to acetic and acrylic acids with the selectivities of 30-36% and 30-38%, respectively. The addition of La₂O₃ and Dy₂O₃ onto the catalyst brought about an increase in the rate of carboxylic acid s formation and its selectivity. The formation rate of the carboxylic acids gave a maximum at 10--20 at% of La content. Enhanced selectivity of carboxylic acids was observed upon the addition of Bi₂O₃. The selectivity of acetone extraporated to 0 sec of W/F was estimated to about 6%, suggesting that there is a reaction path to acetone via isopropenyl radical, isopropenylperoxyl radical. Temperature programmed desorption spectra of NH3 and CO₂from the VP-0 catalysts with and without La₂0₃ indicated that the addition of La₂O₃increased the amount of both weaker acidic sites and weaker basic sites. Comparing the formation rates of partial oxidation products over the La203 containing catalyst and that containing no La₂O₃ in the oxidation of C₃H₈, C₃H₆, and acrylic acid, it is concluded that added La₂O₃ mainly accelerates the rate of reaction via isopropenylperoxyl radical.

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Solid solutions of Pd[(ZrxTi_1-x)_1-y(Mg_1/2W_1/2)_y]O3(PZTMW) were prepared from mixed powders of raw oxides with different degrees of mixing. A relation between their compositional fluctuation (inhomogeneity of composition) and dielectric property was investigated. The mixed powders whose average composition corresponded to PZTMW ((x, y) = (0.2, O.2))were prepared by following three ways respectively. ( 1 ) All component oxides were mixed thoroughly with an agate mortar and a pestle (MIXTURE-1). ( 2 ) Four kinds of mixed powders with the compositions of (x, y) = (0.1, 0.1), (0.1, 0.3), (0.3, 0.1), (0.3, 0.3)respectively were prepared in the same way as (1). Equimolar amounts of them were taken and shook in a bottle (MIXTURE-2). (3) After an oxide mixture containing Zr₄₊, Ti₄₊, and Mg₂₊ was prepared by decomposition of their coprecipitates, PbO, W0₃, and this mixture were mixed thoroughly with an agate mortar and a pestle (MIXTURE-3). Each mixed powder was pressed into a pellet and fired in a PbO atmosphere at 1100°C for 1 h. The compositional fluctuation of the fired samples was observed by a measurement of angle dependence of width of X-ray powder diffraction peaks. The compositional fluctuation was observed in PZTMW from MIXTURE-1 and the larger fluctuation was observed in PZTMW from MIXTURE-2. PZTMW from MIXTURE-3 had almost no compositional fluctuation. The width of dielectric peak at the Curie temperature (Te) approximately corresponded to that calculated from the estimated compositional fluctuation.

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The synthetic process and particle properties of Co₃(PO₄)₂.4 H₂0 were investigated by means of X-ray diffraction, thermal analysis and chemical analysis. Co₃(PO₄)₂-4 H₂O was synthesized by suspending cobalt (1 1) hydrogenphosphate hydrates in deionazed water at 80-96 °C for 24 hs. Its crystal shape was platy of ca.0.5 x 2 pm dimension and light blueish violet (Pe: 27.3%, Y: 30.8%, 2, : 569.2 nm) in color. CO₃(PO₄)24 H₂0changed to Co₃(PO₄)2.5/2 H₂0 (light violet, Pe: 23.0%, Y: 24.9%, 2, : 571.5 nm) as a new phase by dehydrating water of crystallization of 3/2 mole at 222°C, and crystallized to Co, '(PO4)2 by heating at 593 °C through an amorphous phase. Co₃(P0₄)₂⋅5/2 H₂0 changed to Co₃(PO₄)2.4 H20 by holding it in a vessel under the saturated vapor pressure at room temperature. Fine particles of Co₃(PO₄)₂ obtained by heating Co₃(PO₄)₂4 H₂0 are sufficiently applicable to purple pigment with color of deep reddish purple (Pe: 26.0%, Y: 17.6%, A, : 558.8 nm).

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Radon contents in ground waters in Tokyo have been measured since 1976. The correlation between earthquake and radon anomaly will be evaluated easily, when both earthquakes and radon anomalies are a few. In addition, the high reliability of the correlation will be obtained, if an earthquake and an anomaly occur at almost same time. The six earthquakes occurred in 1976'1990 were chosen based on the magnitude (>6.0) and the epicentral distance (<100 km). Radon anomalies shortly before the six earthquakes were investigated at the stations where few anomalies have been detected. Anomalies which can be considered to relate with earthquakes appeared near around the dates of the Ibaraki-Chiba (1985) and the Yamanashi-Kanagawa (1983) earthquakes. The anomalies appeared in 6 d before-4 d after the earthquakes, and no other anomalies had appeared in over 600 d before the earthquakes. Then it is presumed that these anomalies would be earthquake precursors. The anomalies were found at the stations distributed in 50-70 km epicentral distances and on the compress quadrants of the earthquake mechanism.

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The trimerization of methyl isothiocyanate in the presence of triethylamine was accelerated under high pressure to give 1, 3, 5-trimethyl-1, 3, 5-triazine-2, 4, 6(1 H, 3 H, 5 H)-trithione in high yield. Trialkylamines such as triethylamine were good catalyst s of the trimerization under high presssre. Pyridine also catalyzed the trimerization, but '2-methylpyridine and 2, 6-dimethylpyridine had no catalytic activity. The rate of the trimerization of methyl isothiocyanate was proportional to the amount of triethylamine catalyst so far as a limited amount of triethylamine was used. Ethyl isothiocyanate trimerized in high yield on the same reaction conditions as the trimerization of methyl isothiocyanate, however, isothiocyanates having more bulky groups such as propyl, butyl, allyl, phenyl, and cyclohexyl trimerized in poor yields on such reaction conditions. Propyl and butyl isothiocyanates in the presence of DBU trimerized in good yields under 800 MPa at 130 °C f or 20 h. Althouth allyl isothiocyanate, which has a C-C double bond, polymerized by DBU catalyst or at i ncreased temperature, the trimer was obtained in good yield in the presence of triethylamine under 1200 MPa,

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Hydration of dihydromyrcene [1], 3, 7-dimethyl-1-octene [2], and 5, 7-dimethyl-1, 6-octadiene [3] with water or dichloroacetic acid in the presence of several synthetic zeolites was investigated.
Hydration of [1] J with water in the presence of each synthetic zeolites and alkari ion [Al(OH)3] afforded selective formations of dihydromyrcenol [5] J and carvomenthol [6]. With HSZ-620 HOA zeolite, [6] was obtained in high selectivity (85%) for all products from 1]. While with HSZ-640 NAA zeolite, [5] was obtained as a main product (79.5%).
With dichloroacetic acid in the presence of each synthetic zeolites, [6] was obtained as the principal components from [2]. Hydration of [3] 2, 4-dimethyl-7-octen-2-ol [9] with high selectivity as the major product (98%). Studies on the Reaction of Terpenes in the Presence of Synthetic Zeolites. XV.

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The hydroxymethylation of melamine was kinetically investigated in aqueous Na ₂1-1PO₄- N a₃PO₄ and NaHCO₃-Na₂CO₃ buffers. From Arrhenius plots of the rate constants of the base catalyst (PO₄^3- and CO₃^2-) reactions, the activation energies and frequency factors were obtained. On the basis of the kinetics, it was proposed that the reaction occurs by true general base catalysis, and it proceed by the attack of methanediol and the catalyst on the amino groups of melamine by concerted mechanism. The rate-determining step was postulated from the slope of the BrOnsted plot (0.8).

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Poly(2, 5-furandiylvinylene) '(PFV), which is expected to exhibit re latively small bandgap and low ionization potential, was synthesized via new precursor. routes. We found that furan rings in the PFV precursor are cloven and subsequently converted to carbonyl gro ups in the presence of acid. Thus, the removal of hydrochloric acid generated during conversion to PFV from a sulfonium polyelectrolyte precursor was indispensable for the preparation of high quality PFV films. We employed three methods; 1) use of alcohols in place of water for polymerization solvent and preserve from exposure to the air during conversion processing, 2) substitution of a sulfonio-pendant with an ethoxyl group, and 3). substitution of chloride ion with a strong nucleophilic group such as sodium ethoxide.
Chemical defects in PFV films prepared via each ro ute were examined using UV-vis and IR spectroscopy. Spectroscopic observations showed that firstly, the smaller the influence of acid is, the less the chemical defects on the PFV chains are and secondly, three methods employed are very effective to prepare high quality PFV thin films.

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Wet deposition and a part of dry depositions were collected by filtrating bulk sampler and wet/dry sampler in Kobe from June 1986 to May 1990, and at 7 stations over Japan from A pril 1984 to March 1988, and concentrations of dissolved ions and insoluble components in the deposition were determined. These measurements showed that the pH value by filtrating bulk sampler was higher by O.1-0.2 than by wet/dry ampler and that the deposition by the former was 20--40% smaller than by the latter.
The results of experiments to make clear the cau se of the low collection efficiency are as f ollows. Dry deposition by filtrating bulk sampler was 30% lower than that by wet/dry sampler, while filtrating bulk sampler showed high collection efficiency of 90% for wet depoilsition. Sampling error of filtranting bulk sampler was caused by adsorption of chemical species to sampler to sampler surface, as well as by the low collection efficiency of dry deposition.
Filtrating bulk sampler was thought to be the most suitable handy sampler for merly, but, these results indicate that the use of this sampler should be limited only for simple measurement such as, simultaneous measurement at many sites simply for an analysis of spatial d istribution of deposition, preliminary measurement for long -term monitoring by wet/dry sampler and so on.

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Colloidal nickel was easily prepared by reaction of nickel bromide with zinc powder. It was an active catalyst for hydrogenation of carbon-carbon double bonds. Styrene homologs were hydrogenated to afford the corresponding alkanes quantitatively in the presence of the colloidal nickel under an atmospheric pressure of hydrogen. A plot of the volume of hydrogen uptake vs. time gave a straight line. The hydrogenation rates of styrene homologs were compared with that of styrene. The steric and electronic factors of substituent on the double bond affected the rate of hydrogenation significantly.

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The acylation of 1-methylthionaphthalene [1] J with several acid anhydrides was investigated, since the direct acylation of arenethiols proceeded to S-acylation only. The reaction of [1] with an equimolar amount of acetic anhydride cata lyzed by boron trifluoride-diethyl ether complex (BF, .0Et2) afforded 1-acetyl-4-methylthionaphthalene [2 a], while the raction with excess amount of acetic anhydride gave 2-fluoro-4-methy1-6-(4 methylthio-1-naphthyl)-1, 3, 2-dioxaborinylium fluoride [3 a].1-Acy1-4-methylthionaphtahlenes [2], obtained by the re actions of acetic and propionic anhydrides with [1], reacted with propionic and butyric anhydrides to yield 4-alky1-2fluoro-6-(4-methylthio-1-naphthyl)-1, 3, 2-dioxaborinylium fluoride [3].1-Acylacy1-4-methylthionaphthalenes [4], the hydrolysis products of [3], were treated with polyphosphoric acid to produce 3-alkyl- and 2, 3-dialky1-7-methylthio-1-phenalenones [5], respectively, through the ring closure reaction in good yields. In addition, similar acylation of 1-methoxynaphthalne[6] produced 1-acy1-4-methoxynaphthalenes[7] and 4-alkyl-6-(4-methoxy-1-naphthyl)-1, 3, 2-dioxaborinylium fluoride[8]. Fur-thermore, thehydrolysis products of [8] were treated with polyphosphoric acid to produce 3-aslky- and 2, 3-dialkyl-7-methoxy-1-phenalenones [10].

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A mild and convenient method for generation of nitrile oxides is established by dimethyldioxirane oxidation of aldehyde oximes. Aldehyde oximes were converted to furoxanes in almost quantitative yields via dimerization of the corresponding nitrile oxides upon oxidation. When the oxidation was carried out in the presence of alkene or alkyne dipolarphiles, isoxazolines or isoxazoles were obtained.

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Several crystalline compounds isolated from Elsholtzia herb (plant, Elsholtzia ciliata (THUNB.) HYLANDER in China) were triterpenoids, steroids, and flavonoids. Their structures were identified as 9-sitosterol, β-sitosterol βglucoside, ursolic acid, 2 α-hydroxyursolic acid, tormentic acid, negletein, apigenin, and luteolin by the comparison of spectroscopic data with those of the authentic samples.

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A new technique for synthesizing Zn_sFe_3-xO₄powders from α-Fe₂O₃ and Zn under an argon flow by the thermite method is presented. The Zn_xFe₃, O₄ fine powders (O.3 to O.6μm) of single phase were successfully synthesized at 500 °C for 3 h using the powder mixture of Zn/α-Fe₂O₃=0.35 (molar ratio). The saturation magnetization and coercive force of the ZnxFe_3-xO₄ powders were 97 emu/g and O.11 kOe, respectively.

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