Two reoxidation processes appeared at about 160°C and 350°C over the partially reduced γ-Bi₂MoO₆with propene were studied by means of the TPROX method, the XPS measurements, and Raman spectra measurements.
The 160°C reoxidation process was mainly related with the oxidation of the Bi⁰ species to Bi³⁺ states, where the Bi-O bond formation in the (Bi₂O₂²⁺), layers was clearly revealed by the increase of 286cm^-1 absorption peak in the Raman spectra. The apparent activation energy of this reoxidation proce ss was 92 kJ/mol. The 160°C reoxidation process partly involves the reoxidation of the reduced (MoO₄^2-)n layers.
The 350°C reoxidation process was related with the complete oxidation of the Mo⁴⁺ species to Mo⁶⁺states, where the Mo-O bond formation in the (MoO₄^2-), layers was revealed by the increase of the 720 cm^-1 and 855 cm^-1 absorption peaks in the Raman spectra. The apparent activation energy of this reoxidation process was 167 kJ/mol.
It was suggested that the ox ide ions diffused from the oxidized (Bi₂O₂²⁺+)n layers to the (MoO₄^2-)layers at an elevated temperature when the (MoO₄^2-), layers were in the reduced state.

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ZSM-5, ZSM-11 and aluminoferrisilicates were synthesized using 1-butanol, tetrapropylammonium bromide, hexamethylenediamine and tetrabutylammonium bromide as the template. The differences in the physicochemical properties and the catalytic performances for the conversion of methanol to light olefins were investigated. The reaction temperature was controlled to give the conversion of methanol to hydrocarbon of about 40%. In the case of ZSM-5 type aluminoferrisilicate synthesized using 1butanol, the crystallinity was very high and the crystal size (4×9μm) was larger. The amounts of Al and Fe in the zeolite were larger than those of zeolites synthesized using templates other than 1butanol. The FT-IR spectra showed that the structure defects are scarce within the crystal (Table 2, Figs.1, 2).
The cata lytic activity of aluminoferrisilicate was about one fifth of that of the corresponding aluminosilicate zeolite without Fe. The (C₂H₄+C₃H₆) selectivities for ZSM-5 type aluminosilicate and aluminoferrisilicate synthesized using 1-butanol, was higher than those of zeolites synthesized using templates other than 1-butanol, indicating suppression of the oligomerization reactions of ethylene and propylene to C₆⁺ hydrocarbons except BTX at the lower reaction temperature of about 300∼320°C (Table 3, Figs.3, 5, 7).

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A new preparative technique was established by combining each merit of rotation locular countercurrent chromatography (RLCC), counter alternative current chromatography (CACC) and aqueous twophase partitioning method. This proposed technique was applied to separation of D- and L-enantiomers of kynurenine by using 6 % bovine serum albumin (BSA) as an enantiomeric separation reagent in aqueous two-phase solvent system composed of 10% polyethylene glycol 8000 and 5 % disodium hydrogen phosphate. Preparative enantiomeric separation was performed with 200 mg of D, L-kynurenine by CACC and mixer-settler technique: returning 3 min of mixing, 10 min of settling and 1 min of flowing the mobile phase at 1 ml/min. The present method would be useful to the preparative separation of biological compounds without complicated operation.

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Eight novel diazaanthracenophanes (1b- li) with various substituents on the bridging chains (Scheme 1) were synthesized and their photochemical and thermal intramolecular cycloaddition reactions were studied. All of 1(1a- li)photoisomerized to 2, while their thermal reactions were classified into the following three types (Table 2). Type I-compounds undergo the thermal reversion from the intramolecular adduct 2 to 1. Type II-compounds undergo both the thermal reversion and cycloaddition, and type III-compounds do thermal cycloaddition but not the thermal reversion. The difference in the thermochemical reactivities among la, lb, lc and id can be considered to depend mainly on the steric effect similar to that of diazaanthracenoparacyclophanes, decrease of C-N-C bond angle by bulky substituents facilitates the face to face orientation of the two anthracene rings. The difference of enthalpies of the thermal cycloaddition were also compared by DSC measurement (Table 3).

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Cyanoguanidine derivertives such as 3, 9-bis[3- (3-cyanoguanidino) propy1]-2, 4, 8, 10-tetraoxaspiro[5.5]undecane (3a), 1, 1'-bi (3-cyanoguanidine) (3b), 1, 1'- (p-phenylene) bis [3-cyanoguanidine](3c) and 1, 1'- (methylenedi-p-phenylene)bis[3-cyanoguanidine] (3d) were synthesized in 47.7-97.5% yields by the reactions of sodium dicyanamide (1) with the corresponding diamine dihydrochlorides (2a - d) in 1-butanol or in water at reflux temperatures. Thermal curing of epoxy resin (Epikote 828) with 3a - d and certain properties of the cured resins were investigated. The curing of the epoxy resin with 3a - d occurred smoothly at temperatures from 120°C to 150°C. Some properties of the cured resins were largely affected by the structure and the basicity of the cyanoguanidine derivatives. For example, owing to the spiroacetal functional group of 3a, the resin cured with 3a had a low Tg (145°C) and a high Δ (logarithmic damping ratio; 0.21). On the other hand, the resins cured with 3c and 3d had high Tg (167 and 171°C) and low Δ (0.07 and 0.08) due to the aromatic functional groups in 3c and 3d. The resin cured with 3b, which lacks functional substituents also had a high Tg (175°C) and a low Δ (0.08). The rate of the thermal curing reactions increased with the pH value of the curing reagents in epoxy resin. It was therefore concluded that the cyanoguanidine derivertives (3a-d) are well-suited for curing reagents for epoxy resin.

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Perfluorocarbonsulfonic acid membranes, Nafion 117 and Aciplexe which are promising materials for the polymer electrolyte fuel cell, were characterized by using dynamic viscoelastic measurements. Each membrane in wet had three transition points, at about 60°C, about 40°C, and about 130°C. The water which was taken up in the membrane was concerned with the transition point at about 40°C. The transition point at about 130°C was influenced by the state of the side chains having sulfonic acid groups. Both of the transition points at about 40°C and 130°C sifted to lower temperatures with increasing the ionexchange capacity of the membrane.

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The water uptake and the gas permeability of perfluorocarbonsulfonic acid membranes, Nafion 117and Aciplex, which might be used for the polymer electrolyte fuel cell, were examined in water and fumidified gas. The water uptake of Aciplex increased with increasing fumidified gas temperature and with increasing ion-exchange capacity of the membrane. The gas permeability coefficient increased with increasing ionexchange capacity of the membrane but changed only slightly with decreasing water uptake. It estimated that the gas passed through the interface between the amorphous domain and the inner water layer in the membrane.

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Copolymer beads bearing quaternary ammonium groups (RCG-Q) were prepared by treating macroreticular glycidyl methacrylate (GMA)-1, 4-divinylbenzene (DVB) copolymer beads (RG) with hydrogen chloride and following treatment with amines. Triethylamine, N, N-dimethyloctylamine, N, Ndimethyldodecylamine, N, N-dimethylliexadecylamine were used as amines.
Antibacterial activity of the resins was examined for Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) in aqueous suspension. Antibacterial activity increased with increasing amount of quaternary ammonium groups in the resins. The concentration of viable cells became less than 1/10000, when 1 g of the resin was contacted with the bacteria suspension for 6 h. These resins had antibacterial activity for both E. coli (gram negative) and S. aureus (gram positive) in aqueous suspension. Antibacterial activity of these resins was not affected by the chain length of alkyl group in N, N-dimethylalkylamine introduced. The difference of antibacterial activity was observed for the resins composed of different copolymer beads. Scanning electron micrograph showed that bacteria were adsorbed on the surface of RCG-Q.

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The title compounds, R- (NHCH₂CH₂)²-NHCH₂COOH⋅3 HCl([1]; R=n-C₁₀H₂₁-, n-C₁₂H₂₅-, n-C₁₄H₂₉-, and n-C₁₆H₃₃), were prepared by the reaction of the corresponding N-alkyl-ff- (2-aminoeth yl) 1, 2-ethanediamines with sodium chloroacetate (60°C, 4 h) in a mixture of water-methanol (1: 1 v/v)while the pH value of the reaction mixture being maintained between 9-10. Compounds [1]⋅3 HCl were a colorless crystalline substance with definite melting points, and soluble in water and ethanol, and insoluble in acetone, chloroform, ether, ethyl acetate, benzene, and hexane. The critical micelle concentrations (CMC) for [1]⋅3 HCl were determined at 30°C by the surface tension method and the electric conductivity measurement. The surface-active and antimicrobial properties of [1] ⋅3HCl were also evaluated. The trihydrochlorides [1] ⋅3HCl were found to be surface-active compounds. Thus, the dodecyl C12-, tetradecyl C14-, and hexadecyl derivatives C16-[1].⋅3HCl reduced surface tension to 29.9-33.7dyn/cm at their CMCs (5.6, 4.3, and 4.0 mmol/l, respectively); C12-, C14-, and C16-[1] ⋅3HClshowed a foaming ability and a solubilizing power which were comparable or superior to sodium dodecyl sulfate (SDS) and sodium dodecylbenzenesulfonate (DBS). C12- and C14-[1].⋅3HCl showed a good antibacterial activity against Escherichia coli HUT 8047 and Staphylococcus aureus HUT 8051, and C14[1] ⋅3HCl possessed a good antifungal activity against Aspergillus oryzae HUT 2061.

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Polyacrylonitrile (PAN) -based carbon fibers are one of candidate materials for the electrode of a redox flow battery. The effects of the process conditions, such as carbonization temperature, activation and surface treatment, on the surface characteristics and electrochemical performance of the fibers were examined. The results revealed that electrical resistivity, specific surface area of the activated carbon fibers, and 0/C and Cl/C ratios on the surface of the fibers were related to the cell properties. In order to get the carbon fibers with high cell performance, it was preferable to activate the surface of the fibers in the steam and then by electrolyze in hypochlorous acid after the carbonization at 1300°C.

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The sol-gel processing was applied to the fabrication of PbTiO₃ fibers. Pb (OCOCH₃)2⋅H₂O and Ti(OC₃H₇)⁴ were refluxed with stirring in 2-methoxyethanol to form lead (II) 2-methoxyethanolat e and Titanium (IV) 2-methoxyethanolate, respectively. And then both alkoxides were mixed with stirring in 2-methoxyethanol to form lead titanium double alkoxide. This double alkoxide was hydrolyzed. The fibers could be drawn from the sol-solutions after the viscosity reached about 10 poise. The water in the alkoxide solutions was consumed for the hydrolysis and polycondensation reaction progress to give polymerized products, and as a result the viscosity of the solution increases. This indicated that linear polymers were produced through the hydrolysis and polycondensation reaction progress of the solutions.
The PbTiO₃ gel fibers were drawn from the spinnable viscous solutions. The obtained fibers were homogeneous and stoichiometric gels. The fibrous PbTiO₃ gels fired at 600°C formed the well-crystallized perovskite PbTiO₃. Size of the fibers are a few centimeters long and from 10 to 100 μm in diameter.

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Hydrogen peroxide (H₂O₂) is believed to be the primary species that oxidizes atmospheric sulfur (IV)to sulfur (VI) in cloud and rain droplets. Until now only a few measurements of atmospheric H₂O₂ have been performed in Japan. We measured atmospheric and rainwater H₂O₂ in the Hiroshima city, urban area, and the Higashi-Hiroshima city, semi-rural area, in western Japan and compared the difference of H₂O₂ concentrations between both areas. Concentration of atmospheric H₂O₂ measured was in a rang e of 0-3 ppbv and there were diurnal and seasonal variations of the H₂O₂ levels. During the day time, maximum concentration of atmospheric H₂O₂ in Hiroshima was about twice as high as that in HigashiHiroshima. H₂O₂ concentrations in rainwater (0.1-77.5 μM) as well as dissolved inorganic anions were at high levels in initial precipitations (first 15 min) and decreased gradually with precipitation. Summer rain contained high levels of H₂O₂. Gas phase H₂O₂ measured in combustion gases of an incinerator and an automobile was 2.90 and 0.31 ppbv (on average), respectively. With using these values, we estimate that the annual flux of gas phase H₂O₂ from all the stationary combustion sources and automobiles is 2.8×10⁴ and 2.4×10⁵ g H₂O₂, respectively in the Hiroshima area and 5.1×10³ and 2.9×10⁴ g H₂O₂, respectively in the Higashi-Hiroshima area. Our results strongly suggest the importance of stationary combustion facilities and automobile as sources of atmospheric H₂O₂ in urban area.

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Silanols are thought to be key intermediates of chemical vapor deposition of silica film from tetraethoxysilane (TEOS). To get information on the formation of silanols from TEOS, compositions of mixtures of gaseous products and surface concentrations of hydroxyl and alkyl groups were traced by GC and FT-IR in isothermal reactions of TEOS on silica gel. It is observed that formation of both ethylene and acetaldehyde from TEOS on silica gel decreases with decreasing amount of surface hydroxyls. It is concluded that the formation of silanols is accelerated by silanols themselves (i. e., autocatalytic for mation of silanols from TEOS).

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Alumina-supported copper (II) chloride efficiently catalyzed Friedel-Crafts benzylation of aromatic hydrocabons and phenols with benzyl chloride under mild conditions. The recovered catalyst can be readily regenerated and reused without a decrease in catalytic activity. The reaction of benzene with bis (chloromethyl) benzenes gave dibenzylbenzenes in high yields, and the formation of by-products such as polybenzylbenzenes was depressed in contrast to that in the reaction catalyzed by AlCl₃, AlCl₃CH_.NO₂ or FeCl₃.

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A specific freon (chlorofluorocarbon) was converted to a solid state substance. Experiments were performed by means of copolymerization from trichlorotrifluoroethane (CFC113) and ethylene mixtures by cold plasma. The copolymer films have a yellow brown color and a smooth surface. Maximum deposition rate of films from CFC113 and ethylene mixtures is 38 times as large as that from ethylene itself. The results of XPS and IR measurements show the existence of C-Cl and C-F bonds in copolymer films. Measurement of electric resistance shows that the electric resistivity of the copolymer films is higher than 5×10⁶Ω⋅cm.

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