By investigating structure-activity relationships and mode of action of fungicidal pyridyl compound, buthiobate, we developed new biologically active 2- (triazolyl) allyl alcohols which had geometrical (El Z) and optical (RI S) isomers. Among them, (E) -4, 4-dimethyl-1-phenyl-2- (1, 2, 4-triazol-1-yl) -1penten-3-ols show more excellent plant growth regulating and fungicidal activities than Z-isomers. Both activities were quite sucessfully separated, and it was shown that plant growth regulating activity was concentrated in S-enantiomer and fungicidal activity in R-enantiomer. It was also shown that the former inhibited gibberellin biosynthesis in plants and the latter ergosterol biosynthesis in fungi.
After various studies for ecomomical and indusrtial production process, we developed the isomerizationcrystallization method to produce selectively E-isomer of a- (triazolyi)styryl ketones by the combination of isomerization and crystallization techiniques. Optically active (E ) -2- (triazoly1) allyl alcohols were prepared by the enantioselective reduction with lithium aluminum hydride modified with new optically active 2-amino-l-phenylethanols. And then, the practical asymmetric reduction method was developed by using sodium borohydride modified with optically active norephedrine type amino alcohols. Thus, two plant protectants, plant growth regulator ( S-enantiomer) and agricultural fungicide (Renantiomer), were simultaneously realized by these geometrically and optically selective synthetic processes. These two new products also contribute to reducing the application dosages.

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Kinetic studies on the photocatalytic oxidation of oxalate ion (C₂O₄^2-) by peroxodisulfate ion (S₂O₈^2-)in the presence of ruthenium ( II ) complexes have been carried out in an aqueous solution. The oxidative luminescence quenching of tris (2, 2'-bipyridine) ruthenium ( II ) complex ([Ru (bpy)₃]²⁺) by S₂O₈²generated SO₄^-, which could function as an initiator for a series of oxidation reactions of C₂O₄². In the case of tris (2, 2'-bipyrazine) ruthenium ( II ) complex ([Ru (bpz) ₃]²⁺ ), on the other hand, the reductive luminescence quenching by C₂O₄² generated CO₂^-, which could initiate the corresponding oxidation reactions. Photocatalytic reaction mechanisms were analyzed by changing some basic reaction conditions: they were compared with the corresponding oxidation reactions using copper (II) and silver (I)ions as the catalysts.

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Siloxane-bond formation has been studied using IR spectroscopy and TDS (thermal desorption spectroscopy)of tetraethyl orthosilicate (TEOS) adsorbed on silica gel and TPR (temperatureprogrammed reaction) on silica gel. Two main reactions in thermal decomposition of TEOS are proposed on the basis of the experimental results and a reasonable assumption that reactivities of hydroxyl groups are nearly equal both in silanols and on the surface: ( 1 ) formation of silanols from TEOS or its derivatives and ( 2 ) siloxane-bond formation between silanols and TEOS or its derivatives. It is concluded that former reaction is rate determining.

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Preparation of hollow spheres from quartz particles have been reported. First, quartz hollow spheres with CaCO₃ binder were prepared in following process; 1) adhesion of quartz particles (component particles)to oil droplets in alkaline CaCl₂ solution and 2) precipitation of binder CaCO₃ onto quartz surface, by introduction of gaseous CO₂ into the system. The spheres were further calcined at 1000°C, immersed in acidic solution and then washed with distilled water. The resulting spheres were found to form cagelike structure: adjacent particles within a resulting sphere became sintered by calcination, while each sphere was not be fused together. EDX analysis showed intense distribution of Ca solved into sintered phase between quartz particles. XRD pattern of the calcined spheres still indicated intense profile of quartz crystal.
Formation mechanism of quartz hollow spheres with CaCO₃ binder was examined. CaOH ⁺ adsorption onto quartz and oil droplet surfaces was considered to be necessary for the above both steps 1) and 2). It was monitored that the precipitation on the quartz particles would begin first at the irregular edges which face its adjacent component particle, and then extend over the outside or inside of the hollow spheres. Thus it was considered that concentrated CaO from binder CaCO₃ would enhance sintering between the particles by calcination. t A Novel Preparation Method of Hollow Spheres, II.

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Dimethyl carbonate was prepared from CO and methyl nitrite using PdCl₂ catalyst, however, the catalytic activity was gradually decreased, because of a release of Cl from PdCl₂ catalyst. In this paper, we have determined that the release species of Cl from the catalyst was methyl chloroformate, which was formed by the reductive elimination of Cl and methoxycarbonyl ligands from the Pd-complex.
Furthermore, it has been found that methyl chloroformate was effective to activate the Pd catalyst and keep the catalytic activity for a long time in the production of dimethyl carbonate.

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Various kinds of silver. carboxylates are examined as the photosensitive material for forming a printed circuit pattern. These materials deposit silver by UV photolysis and catalyze the electroless plating. From the viewpoint of sensitivity, film homogeneity, and thermal stability, disilver glutamate is revealed to have the most excellent performance. The sensitivity is improved by the chemical sensitizer of inorganic oxides. Zinc oxide is especially effective as a chemical sensitizer of 100 times and provides an easy fixation. The ionization potential of carboxylate ion is concerned in the photosensitivity.

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Trinitrotoluene (TNT) was dispersed into crosslinked poly (vinyl alcohol) (PVA) gel and application of the gel to thin layer chromatography was investigated to separate structural isomers of aromatic cornpounds from each other. Toluic acids and nitrobenzoic acids and their sodium salts were used as model substrates to be separated. Pure water was used as developer. The thin layers were prepared from mixtures of TNT-containing gel (TNT gel) with cellulose powder in various ratios. For comparison, PVA gel without the treatment with TNT (TNT-free gel) was also examined. For toluic acid, the o-, m- and p-isomers showed just the same Rf value on the thin layer prepared from cellulose powder alone and the spots were scarcely separated from each other with addition of TNT-free gel to the thin layer. However, they were successfully separated from each other on the thin layer prepared from mixture of TNT gel with cellulose powder. For nitrobenzoic acid, the o-isomer was separated from the m- and pisomers even with addition of TNT-free gel to cellulose powder and in addition to the separation of the o-isomer, the m- and p-isomers were also separated each other on the TNT gel-containing thin lay er. For sodium salts of the both acids, separation of the isomers similar to the free acids were found on the thin layers containing TNT gel or TNT-free gel, although degrees of the separation were lower than those for the free acids.

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The phosphor films were prepared on a quartz plate by a spin coating method using a sol-gel solution. The spin rate can be varied from 1000 to 4000 rpm and the spinning was carried out for 1 min under the irradiation of an infrared light. The dried sample was calcined in air at various temperatures for 1 h. The film thickness and the emission intensity decreased as spinning rate increased. The emission intensity of the phosphor film prepared by this method was dependent on the film thickness and firing conditions. The emission properties of phosphor films were discussed on the basis of the surface state of phosphor films.

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Fogwater had been collected from 1992 to 1993 at the midslope of Mt. Oyama (a. s. l.1252 m) at the southwest of the Kanto Plains. The concentrations of five species of aldehydes, formaldehyde, acetaldehyde, glyoxal, 2-oxopropanal, and hydroxyacetaldehyde, in fogwater were measured. The maximum value of the total concentration of these aldehydes was 187μM (April 1992). The maximum concentration of glyoxal, whose concentration was the highest among these aldehyde, was 97μM (June 1992). Much aldehydes were contained in highly polluted fogwater and the aldehyde concentrations in fogwater increased with the decrease of pH. When the lowest altitude of the upslope fog rose up to the sampling station, the total concentration of aldehydes increased. The fraction of aldehyde with a high Henry's law constant increased with the elevation of the lowest altitude of fog. Aldehyde concentrations in fogwater are affected not only by liquid water content and air pollution but also by the lowest altitude of fog.

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Direct separation of aromatic nitro compounds from aqueous solution using supercritical carbon dioxide was studied. When aqueous nitrobenzene (NB) solution was added to an extractor to remove NB by blowing supercritical carbon dioxide, the removal ratio of NB depended upon the temperature, pressure, quantity and velocity of supercritical carbon dioxide or an amount of aqueous solution. The ratio was independent of the concentration of NB (less than 400 ppm). The temperature dependence of removal ratio was small under less than 75 kg/cm2 of pressure, and a certain amount of NB in 100 ppm of NB aqueous solution was removed under less than 50 kg/cm2 of pressure. This result was different from that of the regeneration of activated carbon adsorbing NB, but the differrence was explained by the difference of the removal mechanism of NB, between the direct separation from aqueous solution and the regeneration of activated carbon. The removal ratios of 6 kinds of aromatic nitro compounds were observed to relate to regeneration ratios of activated carbons adsorbing these compounds, but not to relate to their aqueous solubilities. The removal ratios tend to decrease in both the cases where the electron affinity of substituent group is too strong or too weak.

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The photochemical decomposition behavior of hexacyanoferrate(^) ion ([Fe (CN)₆]^3-) i n alkaline solution using ultraviolet light in nitrogen atmosphere was reported in a previous paper. In this paper, Cu/TiO₂ (anatase) composite powders were added to promote the photochemical decomposition of [Fe (CN)₆]^3-, a nd ozone (O₃) was used as oxidizing agent of CN^-, based on the reports of t itanium (IV) oxide ( TiO₂) as the photocatalyst of [Fe (CN)₆]^3- to aquapentacyanoferrate (III)ion ( [Fe (CN)₅(OH₂)]^3-) and copper (Cu) as the oxidizing catalyst of CN- to OCN^- in ozone atmosphere. Effect of Cu/TiO₂ composite powders addition to [Fe (CN)₆]^3- CN^- and OCN^- solutions in the flow stream of O₃ under irradiation was studied by means of VIS-UV spectroscopy, ion chro matograpy and chemical analysis.
As the results, it was fo und that the reduction-decomposition of [Fe (CN)₆]^3- to [Fe (CN)₅(OH₂)]^3- and CN^- was accelerated due to suppression of the reaction of [Fe (CN)₆]^3- to hexacyanoferrate(II)ion ([Fe (CN)₆]^4-) by the addition of Cu/TiO₂ in O₃ atmosphere under irradiation. However, under the same condition in d ark, [Fe (CN)₆]^3- did not degrade even in the flow stream of O₃. The oxidation rea ction of CN- to OCN- by the addition of Cu/TiO₂ in O₃ under irradiation was found to be promoted much more than under the same condition in t he absence of Cu/TiO₂. In addition, the decomposition of O CNto CO₂ and N₂ in O₃ seemed to occur simultanously with the hydrolysis of OCN^- in acidic solution.

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Malonic acid was decomposed by irradiation with ultrasonic waves. The main gaseous products were CO, CO₂ and H₂. In order to compare the products, several decomposition methods were carried out. Carbon monooxide was detected only in the sonolysis. In this reaction, acetic acid and formic acid were confirmed as intermediates. The temperature effect on products distribution was also determined.

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Highly concentrated state (10₂₁-10₂₂ particles/m₃) could be achieved in hexane for particles with 2.7nm mean diameter without aggregation by the gas flow-cold trap method combined with cationic surfactants such as (2-dodecylhexadecyl)trimethylammonium chloride (g-C28TAC). The preservation of the particle size distribution in the concentrating and drying process was confirmed by electron microscopy. However, the particle size changed during the processing in case of anionic surfactants such as sodium 1, 2-bis (2-ethylhexyloxy carbonyl) ethanesulfonate. Contact-free silver clusters with 1nm diameter could be prepared in hexane with g-C28TAC by a modified gas cold trap method.

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Synthetic fluorohectorite was pillared with zirconia in the presence of poly (vinyl alcohol) (PVA). The interlayer distance of the prepared clay was determined by X-ray powder diffraction; the interlayer distance was 20 Å in contrast to 2.4 Å for raw clay. The nitrogen adsorption isotherm observed was in agreement with BET equation, indicating that the pore formed in the synthetic fluorohectorite was large enough to assure the multi-layer adsorption of nitrogen. The pore size distribution determined from the parallel plate pore model; the main distance between the plates was ca.18 Å.
It was found that pillaring in the presence of PVA resulted in a preparation of zirconia-pillared synthetic fluorohectorite having a interlayer distance of 20 Å.

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Intercalation of alkylamines into α-tin (IV) bis (hydrogenphosphate) [α-SnP] was investigated in aqueous and benzene solutions by chemical and XRD analyses. The interlayer distance of the intercalation compounds was proportional to the number of carbon atoms (n_c) in alkylamines, in the wide range of n_c 1 to 16. The alkylamines in α-SnP formed bilayer, where only three alkylamine molecules were bonded to every four P-OH groups present on the α-SnP layers. Their alkyl chains with a trans-trans conformation inclined roughly at 65° with respect to the α-SnP layer.

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Chlorination of 2-acetamidopyridines (1), such as 2-acetamidopyridine (la), 2-acetamido-4-methylpyridine (lb), 2-acetamido-6-methylpyridine (1c) and 2-acetamido-4, 6-dimethylpyridine (1d) was investigated. Chlorination of compounds (1) using slight exess of chlorine in aqueous Na₂HPO₄ gave 2(N-chloroacetamido) pyridines (2) as intermediates. Compounds (2) were rearranged under acidic conditions to give 2-acetamido-5-chloropyridines (3) in good yield.
Namely, 2-acetamido-4-methylpyridine (lb) was reacted with molecular chlorine in aqueous Na₂HPO₄ or CH₃CO₂Na to produce 2- (N-chloroacetamido)-4-methylpyridine (2b) which was conform ed to its structure by ¹H-NMR proton shifts. The intermediate (2b) without isolation was treated under various conditions. By addition of catalytic amount of acid, the rearrangement was accelerated. From these results, it is estimated that this reaction takes Orton rearrangement like mechanism.

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Furil underwent an efficient photoreduction to selectively afford furoin in benzene and acetonitrile containing triethylamine. A thermodynamic analysis of the reaction suggests the operation of an electrontransfer mechanism. Small steric effects of tertiary amines used on the quantum yields for the formation of furoin was explained in terms of a loose radical ion pair formed by an electron transfer from the ground-state amine to the excited singlet-state furil. A pronounced charge transfer-type interaction between the amine radical cation and benzene molecules in the solvent cage was proposed to interpret a high reactivity of furil in the nonpolar solvent, benzene.

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It has been tried to solidify dye laser, but the attempt was not succeeded, yet, for highly fading speed of the laser dyes. We investigated the photofading rate of Rhodamine 6G, the dye for dye laser, in vinyl polymer matrices, and it was found that the fading rate was proportional to e value of the monomer which composes of the polymer.
It was also found that the formation of inclusion complex by cyclodextrin was not effective in such polymer matrix containing poly (methyl methacrylate).
It was already reported that the photofading of Rho damine 6G in poly (methyl methacrylate) was reduction reaction. This phenomena were due to the fact that the hydrogenated position of Rhodamine 6G was not included in cyclodextrin. On the other hand, the photofading rate of Rhodamine 6G in poly(vinyl alcohol) matrix was very slow and was further decreased by cyclodextrin.

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