Oxide clusters such as [n-Bu₄N]₂[ { (η ³-C₄H₇)₂Rh}₂(V₄O₁₂)], [( MCp*)₄V₆O₁₉] (M = Rh, Ir), and [(MCP*)₄ Mo₄O₁₆]( M = Rh, Ir) were attached on a silica surface as a molecular model for oxide catalysts and supported metal catalysts. The structure and electronic state of the attached clusters were investigated by EXAFS, FT-IR, XPS, TPD, and FT-Raman spectroscopies. Kinetic studies of catalytic reactions such as hydroformylation, oxidation, hydration, and metathesis were carried out. Coordination unsaturated sites appeared upon evacuation of attached vanadium oxide clusters or the photo-reduction of attached molybdenum oxide cluster under CO, which were characterized on a molecular level. The kinetic study related to the cluster structure revealed that the coordinatively unsaturated sites produced by the thermal evacuation or the photo-reduction were catalytically active for selective propene oxidation and metathesis reactions. This study showed that attached oxide clusters were promising model, which can be well characterized on a molecular level, of oxide catalysts and/or supported metal catalysts.

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Tebufenpyrad was discovered by Mitsubishi Chemical Corporation during intensive research on pyrazole derivatives in 1987 and was successfully used in France, Belgium, Switzerland, and then Japan in 1993. Tebufenpyrad is a novel acaricide belonging to the pyrazolecarboxamide group and has high activity against various mite species including Tetranychus spp. and Panonychus spp. due to its rapid action at all development stages of mites. This paper describes the drug design for tebufenpyrad, lead generation, lead optimization, structureactivity relationships of pyrazole-5-carboxamide derivatives; physical and chemical properties, biological characteristics, and the synthesis of tebufenpyrad.

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Ethanol synthesis by CO₂ hydrogenation was investigated using promoted Rh/SiO₂ catalysts. Methane was produced predominantly over the unpromoted Rh/SiO₂ catalyst even under the pressurized reaction conditions. In order to improve ethanol formation over Rh/SiO₂, more than 30 kinds of additives were tested. As a result, the following four additives, Li, Sr, Fe and Ag, promoted ethanol formation. Among the four additives, Li showed the most remarkable effect. Ehtanol selectivity was 15.5%with 7.0% CO₂ conversion at 5 MPa, 240°C, 100 ml/min and H₂/CO₂= 3. The results of in-situ FT-IR suggest a possible reaction mechanism via CO intermadiate, and a close relationship between intermadiate CO species adsorbed on the catalyst and ethanol selectivity of CO₂ hydrogenation. It is speculated that Li changes electronic state of Rh.

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Single crystals of a new ternary intermetallic compound Nb₅Sn₂Ga have been synthesized by a self flux method using molten tin as a solvent. Solid solution range of the compound is very narrow. This compound is probably a Daltonide-type ternary intermetallic compound. The crystal structure shows a tetragonals ymmetry, s paceg roup D_4h¹⁸-I4/mcm, ordered W₅Si₃-typset ructure. Latticep arameterso f the single crystals of Nb₅Sn_1.97Ga_1.06, which composition is the nearest to the stoichiometric composition, are a 1.0586 (2), c= 0.5177 (1)nm and V= 0.5802 x 10^-27 m3. The unit cell volumes decrease with increasing gallium content in the chemical formula. As a result, intermetallic distances Nb to Nb also decrease. The values of the T_c (midpoint) increase with increasing gallium content in the chemical formula: 1.69, 1.75 and 2.13 for Nb₅Sn_2.12Ga_0.94, Nb₅Sn_1.97Ga_1.06 and Nb₅Sn_1.95Ga_1.08, spectively.

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In order to examine the influences of the reaction temperature and time on the hydrolysis of a-tricalciurn bis (phosphate) (α -TCP) in solubilized collagen solutions of pH 5, chemical analysis of the solutions after the reaction, and X-ray diffraction, Fourier transform infra-red spectroscopy, thermal analysis and chemical analysis of the hydrolyzed products were carried out. Calcium hydrogenphosphate dihydrate (DCPD) was at fir st formed and then hydroxyapatite (HAp)and octacalcium dihydrogenhexakis (phosphate) (OCP) were formed at 20-30°C. However, the formation of DCPD was not detected at 35 40° C. The rates of formation for HAp and OCP increased with the increase of the reaction temperature, and the presence of collagen accelerated the formation to them. The content of collagen increased with the increase of reaction temperature and time. Ca/P molar ratios of the hydrolyzed products varied ca.1.3 to 1.5, because DCPD was formed in early period of hydrolysis and the formed HAp was nonstoichiometric hydroxyapatite in addition to the formation of OCP. Further, it was suggested from the results of investigation for chemical kinetics that α -TCP is hydrolyzed to HAp more easily by the presence of collagen.

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Dark green crystals of sodium tungsten bronze (Na_xWO₃) were grown from high-temperature solu tion of Na₂O-WO₃ by a slow cooling method. Solution growth of Na, WO₃ crystals was conducted by heating mixtures containing 12.5 to 25 mol% Na₂O at 1100° C for 10 h, followed by cooling to 800° C at a rate of 5° C h^-1 and subsequent quenching to room temperature. Hexahedral crystals of Na_xWO₃, up to 12 x 10 x 5 mm in size, were obtained. The crystal sizes were dependent on the concentration of Na₂O in solutions. The most suitable Na₂O concentration was 15 mol%. The hexahedral crystals grown be longed to the orthorhombic system and were bounded by {100}, {010} and {001} faces. On the basis of the determination of sodium and lattice parameter c, the composition of sodium tungsten bronze crystals was found to be Na_0.025WO₃. The density of crystals, pycnometrically determined, was 7.31 ± 0.02 g cm^-3. The resistivity of crystals had the values in the range 5.7 to 8.2 Ω cm. The high-temperature solu tions containing 27.5 and 30 mol% Na₂O produced only sheet-like Na₂W₄O₁₃ crystals.

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In order to determine simultaneously major inorganic anions including total carbonate and common inorganic anions (Cl^-, NO₂^-, NO₃^-, and SO4^2-) in various environmental waters, the ion chromatography with an indirect UV-photometric detection using various benzenepolycarboxylate (o-phthalate, 1, 2, 4-benzenetricarboxylate, and 1, 2, 4, 5-benzenetetracarboxylate) eluents and columns packed with a silica based anion-exchanger (TSKguardgel QAE-SW, capacity: ca.0.3 mmol OH^-/g) were investigated. When a 0.5 mmol/dm³ 1, 2, 4-benzenetricarboxylate eluent at pH 6.0 and a 15 cm separation column were used, the best separation and detection sensitivity of the anions were accomplished within 15 min without the interference of coexisting Mg²⁺ and Ca²⁺ in sample solution. The detection limits (S/N = 3, i njection volume: 20, μl) under the indirect UV-detection at 270 urn were 240 ng/ml for HCO₃^-, 15 ng/ml for Cl^-, 22 ng/ml for NO₂^-, 33 ng/ml for NO₃^-, and 48 ng/ml for SO₄^2-. The calibration graphs by peak area method were linear up to at least 10 mmol/dm³ for HCO₃^-, 2 mmol/dm³ for monovalent anions, and 1.5 mmol/dm³ for SO₄^2-. This method was successfully applied for the determination of the anions in various environmental waters including river, pond, and forest soil waters.

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The oxidation reactivity of ferrocene and 1, 1', 3, 3'-tetra-t-butylfei-rocene with air was measured in several solvents in the presence of trichloroacetic acid. In chloroalkanes, the k_tetra/k_Fc depended on dielectric constant of solvent, suggesting the increasing polarization due to the I-effect of t-butyl group. In dichloroethane-ethers or dichloroethane-alcohols, a linear correlation between k_tetra/k_Fc and -pKa of ethers or alcohols was observed. This is probably because the bulky t-butyl group on the cyclopentadienyl ring hinders the protonation of iron atom by the solvated proton.

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Results were reported of stopped-flow spectrophotometric studies on the ligand-exchange of Cu (II)complexes of aminopolycarboxylic acids with D-penicillamine (PasH). The aminopolycarboxylic acids examined were N, N-bis (2-hydroxyethyl)glycine (BHEG), iminodiacetic acid (IDA), N (2-hydroxyethyl) iminodiacetic acid (HIDA), N (2-carboxyethyl) iminodiacetic acid (CIDA), nitrilotriacetic acid (NTA), and nitrilotripropionic acid (NTP). A final product in a series of the ligand exchange reactions was a Cu(II) complex of penicillamine, Cu(II)(Pas)₂, which was fairly stable towards redox reaction and showed S → Cu(II) charge transfer absorptions at λ _max = 332 nm and 390 nm. All the complexes, except for that with NTA, as well as those with glycine and triethanolamine, formed transients which were assignable to mixed-ligand complexes with D-penicillamine showing a single LMCT band at λ _max = 345350 nm and d-d transition bands at λ _max=6 7 0-700 nm. Formation of the ternary complexes was extremely rapid so that the rate constant ki+ could not be determined. The rate of ligand-exchange from the ternary complex to Cu(II)(Pas)₂ was varied depending on the electrostatic property and number of pendant ligands; 2-hydroxyethyl and carboxymethyl groups. The rate constants k₂+ of ligand-exchange in the ternary complexes were arranged in decreasing order as follows; (Pas)Cu(II)(IDA)> (Pas)Cu(II)(BHEG) > (Pas)Cu(II)(HIDA) > (Pas)Cu(II)(CIDA) ≥ (Pas)Cu(II)(NTA).

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Thermosensitive terpolymers were synthesized by graft terpolymerization of N-isopropylacrylamide (NIPPAm) and termonomers such as butyl methacrylate (BMA), 2-hydroxyethyl methacrylate (HEMA) and methacrylic acid (MAc) on poly (vinyl alcohol) (PVA) and the terpolymer membranes were prepared by evaporating solvent from their dimethyl sulfoxide solution. The introduction of hydrophobic monomer such as BMA and of hydrophilic monomer such as HEMA decreased and increased the swelling of the terpolymer membranes in water and shifted the transition temperature to lower and higher temperature, respectively. On the other hand, the PVA-g-(NIPAAm-MAc) membranes containing carboxyl groups exhibited an abnormal swelling behavior in water depending on the content of carboxyl groups. The swelling ratio of PVA-g- (NIPAAm-MAc5) (Number after MAc represents the weight ratio of MAc in monomer mixture in feed) and PVA-g- (NIPAAm-MAc10) increased with increasing temperature, although the swelling ratio of PVA-g-NIPAAm decreased with increasing temperature, in particular, decreased drastically above 30°C. The swelling ratio of PVA-g (NIPAAm-MAc30) and PVA-g- (NIPAAm-MAc50) was very small in the temperature range (10-45°C) and the phase-transition temperature of the membranes could not be observed. This abnormal swelling behavior is mainly attributed to the hydrogen bonding between amide groups and carboxyl groups and hydrophobi c interaction based on a-methyl groups in MAc moiety in the terpolymer membranes. Temperature d ependence of the swelling of PVA-g (NIPAAm-MAc5) at increasing temperature was not the same as that at decreasing temperature. The permeation of Li⁺ through PVA-g- (NIPAAm-MAc5) treated with glutaraldehyde was investig(ated by using the system containing 0.005 mol dm^-3 HCl (left side) and 0.005 mol dm^-3 LiOH right side). The transport rate of Li⁺ increased with increasing temperature up to 30°C and th en d ecreased drastically above the temperature. The uphill transport of Li⁺ was also observed at 25°C and 30°C.

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Acid deposition on plains has been widely monitored. However, deposition monitoring in mountainous regions has been much less common due to the difficulty of access. We monitored acid deposition at eight sites in mountainous regions in Japan from June till October in 1992. The pH of deposition samples obtained from mountainous regions was in the, range from 4.7 to 5.3, slightly higher than that measured in samples from plains. The relative abundances of anions and cations were mainly nss-SO₄^2-> NO₃^- > nss-Cl^- and H⁺ > NH₄^- > nss-Ca²⁺. The [NO₃^-]/([NO₃^-]+ [nss-SO₄^2-]) ratio was 0.10.2 at sites of higher than 1500 m and greater than 0.3 at sites lower than 1500 m altitude. Ion concentra tions in acid deposition in mountainous regions were lower than those in plains, however rainfall in mountainous regions was greater than that in plains. So total ion deposition in mountainous regions at some sites was similar to that in plains.

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The diamagnetic susceptibilities of alkyl phosphates, N-alkylpyridinium compounds and various coenzymes were determined by Gouy's method. The susceptibility for phosphate group ( · PO₄^-· ) was found to be 40.5 x 10^-6 cm³ mol^-1. The molar diamagnetic susceptibility of dipalmitylphosphatidylcholine was obtained to be 512 x 10^-6 cm³ mol^-1. The result was almost in accord with the estimated value, 505 x 10^-6 cm³ mol^-1, obtained by Pascal's additive law. The molar diamagnetic susceptibilities of various coenzymes, NAD⁺, NADH, NADP⁺, FAD were determined to be 342, 341, 370, 416 x 10^-6 cm³ mol^-1, respectively.

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3-O-[(E)-3 (Hexadecyloxycarbonyl) acryloyl] -α -D-glucopyranose (gHDF) and 3-O-[(E) -3-(hexadecyloxycarbonyl) acryloyl] 1, 2: 5, 6-di-O-isopropylidene-α -D-glucofuranose (digHDF) were synthesized as a glycolipid a nalog having polymerizable group. gHDF and digHDF were polymerize d in the presence of α, α '-azobisisobutyronitrile to give polymers [poly (gHDF) and poly (digHDF)]. The molecular assembly of gHDF and digHDF was examined by the solubilization of sodium 8-anilino -1-naphthalenesulfonate (ANS) as a fluorescence probe. From the relationship between the concentration of glycolipid a nalogs and the fluorescence intensity, a sharp increase in fluorescence inten sity for all of analogs was observed in chloroform at 10.0 x 10^-3, 0.8 x 10^-3, 2.5 x 10^-3, and 1.5 x 10^-3 mol. L ^-1 fo gHDF, poly (gHDF), digHDF, and poly (digHDF), respectively. Therefore, glycolipid a nalogs obtain ed were found to form a molecular assembly in chloroform.

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Precipitation samples were collected every rain-fall during eight months from June 1994 to January 1995 at Joetsu, Niigata, Japan. Dissolved ions such as Na⁺, K⁺, NH₄⁺, Mg²⁺, Ca²⁺, Cl^-, Br^-, NO₃^- and SO₄^2- and pH value were analyzed in 48 samples obtained. The concentrations of major ions were distributed near those observed in a background area of the Sea of Japan. The strong contribution of the coastal seawater to the chemical composition of precipitation was observed in the period between October and January. In precipitations from October to November, good correlations for each pair of [NH₄⁺], [Ca²⁺]_nas, [K⁺]_nas, [NO3^-] and [SO₄^2-]_nas imply the presence of definite composition of dissolved species. From December to January, a regression line of [NH₄⁺]= 0.305[SO₄^2-]_nas+ 0.820[NO₃^-] -6.09 was obtained with a good correlation coefficient.

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The hydrogenation of linalool over Pt/TiO₂, Pt/SiO₂, TiO₂, Pt black, and mechanically mixed of Pt black and TiO₂ was studied. By using Pt/TiO₂ catalyst, the hydrogenation took place in high regioselectivity; the terminal double bond in 1-position took precedence of the inner double in 6-positon. Similar results were also observed in the reactions of linalyl acetate, nerolidol, 5-methyl-1, 4-hexadien-3-ol and 1, 5-nonadien-4-ol.

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