Anodic photocurrent on a polycrystalline ZnO electrode in analkaline solution was increased with addition of D-glucose. The increase in photocurrent due to glucose depended on the concentration of glucose and the intensity of light irradiated. No dissolution of the ZnO electrode was observed, but carbon dioxide was analyzed quantitatively as a final product. We suppose that ·OH radicals formed on the ZnO by a hole reaction oxidize glucose to give a intermediated reactive radical, from which an electron is injected to the conduction band of ZnO resulting in formation of an oxidized molecule. Then in the next step the oxidized form is further oxidized by the ·OH on the ZnO surface. These step-by-step oxidation reactions may continue until the final stage of carbon dioxide formation. In fact when gluconate or glucarate was added to the electrolyte solution, the currentdoubling effect was observed. From these results we propose a machanism of oxidation of D-glucose on the ZnO photoelectrode.

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The hydrophobic-hydrophilic change of the powder surface due to the decomposition of coated hydrophobic materials is applied to the choice of the photoactive TiO₂ powders. Surface modification treatment with the hydrophobic material let the powders of TiO₂ float on water, though the TiO₂ powders without the treatment sink to the bottom of the beaker. Under irradiation of a UV light, only some part of TiO₂ powders floated have started to drop to the bottom. We have found that the rate of the sinking depends on the decomposition rate of the coated material. As the TiO₂ powders which are effective for photocatalytic reaction can decompose the coated molecules, we can choose the efficient photoactive TiO₂ powders from its sinking rate.

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Adsorption of several inorganic ions from aqueous solution on commercial and their modified activated carbons has been studied. Adsorption tests of halide ion from 1×10^-3mol/l halide solution and sodium ion from 1×10^-4-2×10^-3mol/l sodium ion solution were carried out at various pHs. Halide ion was adsorbed in acidic region and its uptake increased with the lowering of pH (Figs.2, 5). The adsorption of halide ion was largely affected by the kind of halide ions. The order of halide ion uptake was follow; I^->Br^->Cl^- (Fig. 5). Hydrogen ion was simultaneously adsorbed on activated-carbon with halide ion, and the ratio of the adsorbed hydrogen ion to the adsorbed halide ion, H/X, was approximately 1.0 (Fig. 3). Insoluble ashes in activated carbons exerted no effect on the adsorption of these ions (Fig. 6). The activated carbon made by a steam activation method showed higher adsorption ability for these ions than one made by a zinc chloride activation me thod. Hydrogenation or outgassing of activated carbon at high temperature improved the adsorption ability for these ions. On the other hand, oxidation of activated carbon lowered the adsorption ability for these ions (Figs. 8, 9).
Sodium and hydroxide ions were adsorb ed in alkaline region and their uptakes increased with an increase in pH (Fig.2). The amount of adsorbed hydroxide ion was appreciably larger than that of adsorbed sodium ion (Figs. 2, 4). The influence of activation method and the surface modification of activated carbon on the adsorption of these ions were reversed to that on the adsorption of halogenide and hydrogen ions (Figs. 8, 9). The adsorption of halide and hydrogen ions and the adsorption of sodium and hydroxide ions can be explained by a basic surface oxide mechanism and by an ion-exchange mechanism, respectively.

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Both reaction network and selectivity on homogeneous hydration of acrylonitrile were investigated under the basic catalysts. The hydration was carried out in the large excess of water at a pH range of 0.9-12.1 and at a temperature range of 45-65°C. Only acrylamide was produced by the hydration of the cyano group in the acidic media, which agrees with the results reported in the literatures. Acrylamide, which was first identified in this experiment, ethylene cyanohydrin and bis(2-cyanoethyl) ether were obtained by the hydration at either cyano group or vinyl group in the basic catalysts.
A computer simulation method was applied to analyze t he kinetics of the base-catalyzed hydration of acrylonitrile. It was confirmed that the hydration proceeded by the following mechanism:
CH2=CHC≡N+H₂O_??_HOCH₂CH₂C≡N (1)
HOCH₂CH₂C≡N+CH₂=CHC≡N_??_(N≡CCH₂CH₂)₂O (2)
CH₂=CHC≡N+H₂O_??_CH2=CHCONH₂ (3)
where κ₁, κ₂2, κ₃, and κ₄, show the reaction rate constants. The value of k2 was 14---77 times greater than that of others. It is concluded that the main product in the basic catalysts is the bis(2-cyanoethyl) ether.
The hydration mechanis m of both cyano and vinyl group was considered by use of the resonance hybrid model of acrylonitrile molecule.

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The acidic properties of H₃PW₁₂O₄₀ and its metal salts were measured by means of the temperature-programmed desorption (TPD) method and the indicator method. There was no relationship between the order of acid strength of these salts measured by TPD method and that measured by the indicator method. There were also curious phenomena observed in TPD that the desorption peaks appeared at the same temperature regardre ss of the employed probe molecules, NH₃ and pyridine, which have different basisity. Acidcatalyzed reactions, dehydration of ethanol and isomerization of cis-2 -butene, were carried out in order to see which method was appropriate for explanation of acid catalysis. The catalytic activity of various salts in both reactions had a good correlation with th e acid strength measured by the indicator method.
The fact that no relationship was observ ed between the activity and the acid strength measure by TPD, which is widely utilized and regarded as a reliable and convenient method for the measurement of acidity, indicates that the adsorption of basic molecules was ruled by facters other than the interaction between the absorbed basic probe mol ecules and acid sites.
This res ult was attributed to the absorption property of heteropoly compounds; that is, heteropoly compounds absorb polarized molecules such as NH₃ and pyridine into their bulk and stabilize them in the lattice accompanied by the rearrangement of secondary structure of heteropoly compounds so called pseudo-liquid phase. This is one of the significant differences between solid acid with “rigid” structure such as zeolite, and Si0₂-Al₂0₃, etc. and that with “flexible” structure of heteropoly compounds.

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The preparative methods of the Raney-type Ni-Al₂O₃, Ni-Cr-Al₂O₃, Ni-Mo-Al₂O₃ and Ni-Mo-Cr-Al₂O₃ catalysts were examined with emphasis on their thermal stabilities for high temperature methanation of CO. The catalysts were prepared by oxidation and calcination of Raney nickel in air. Addition of (NH₄)₂Cr₂O₇ and (NH₄)₆Mo₇O₂₄ into sodium hydroxide aq. soln. upon leaching Ni-Al alloy were found to be effective for the homogeneous distribution of alumina and promoters in the catalysts (Figs.1, 3). Interactions between nickel oxide and other constituent oxides in the precursors increased with increasing the temperature and period of calcination, except the case of the single addition of Cr (Table 2). For the precursors of a Ni-Mo-Cr-Al₂O₃ catalyst, interaction between NiO and the constituent oxide increased markedly in the calcination temperature range from 600 to 650°C. The fraction of free NiO attained below 30%, and a decrease in the crystallite size of NiO was observed (Table 2). Catalysts containing Mo showed higher methane selectivity than those free from Mo (Fig.4). The carbon content of the catalysts after the thermal stability test decreased in the following order: Ni-Mo-Al₂O₃>G-65 (commercial Ni-Al₂O₃)>Ni-Al₂O₃≈Ni-Mo-Cr-Al₂O₃>Ni-Cr-Al₂O₃, as shown in Table 4. The relationship between the thermal stabilities of the catalysts and the catalyst properties, such as the amount of free nickel, homogenuity of the catalyst components, and the species of promoter were discussed. Simultaneous addition of Cr and Mo as promoter was found to be effective in improving the thermal stabilities of catalysts.
Ni-Mo-Cr-Al₂O₃ calcined at 650°C for 16 h exhibited high thermal stability (Fig.6) due to the depressed nickel sintering and carbon deposition (Table 3, 4).

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It was found that MgNdB₅O₁₀ crystals were grown from high-temperature solutions of K₂B₄O₇ flux.
K₂B₄O₇ flux was chosen on the basis of the guide previously proposed by the authors. According to the solubility measured, about 183 g of MgNd135010 was dissolved i n 100 g of K₂B₄O₇ at 1273 K. Therefore, K₂B₄O₇ flux was expected to be suitable for the growth of objective crystals.
The growth was conducted by heating mixtures at 1273 K for 5 h followed by cooling to about 973 K at a rate of 4(or 2) K/h. MgNdB₅O₁₀ crystals up to 3.7 x 2.5 x 0.5 mm in size were grown. These crystals were thin (or thick) plate with well-developed {102} faces in shape, reddish purple in color and transparent. A density of the crystals, pycnometrically determined, was 4.08±0.03 g/cm₃. A melting point of the crystals, determined by DTA, was 1346±5K.

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A flow injection method was developed for the determination of hydroquinone, pyrocatechol, resorcinol, and pyrogallol by utilizing the redox reaction with iodate ion. Mixed solution of sulfuric acid (1 mol·dm^-3) and potassium bromide (0.42 mol·dm^-3), and potassium iodate solution (10^-4 or 4×10⁵ moli·dm^-3) were pumped at a rate of 0.35 cm³min^-1, and pure water at a rate of 1.14 cm³min^-1. The decrease of iodate ion concentration, resulted from the redox reaction with the sample, was monitored by measuring its reduction current with a platinum wire (0.5 mm o. d., 20 mm long) electrode held at +O.65 V (vs. a silver tubing) and a silver tubing (1.2 mm i. d., 20 mm long) electrode. Linear relations were found between the sample concentrations and the peak heights when 20 μl of the sample was injected. With the proposed method, hydroquinone (5×10^-5-10^-5 mol·dm^-5), pyrocatechol (5×10^-5-10^-3 mol·dm^-3), pyrogallol (2×10^-5-5 x 10^-4 mol·dm^-3), and resorcinol (4×10^-6-2 x 10^-4 mol·dm^-3) were determined with relative errors of less than 2.7, O.9, 0.8 and 3.6%, and coefficients of variation of less than O.7, 1.5, 1.2 and 0.7% respectively. It was possible to determine 24 samples per hour.

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The Claisen rearrangement of allyl[o-(or p-)substituted phenyl] ethers was carried out, and it was observed that the effect of the substituents on the reactivity was in the following order:
o-COOH>o-OH>o-NHCOCH₃>o-NH₂>o-CH₃O>o-COOCH₃>ρ-OH>H>ρ-COOH
Allyl phenyl ethers with protic substituent in ortho position showed higher reactivity than any other cases.
It was considere d that the reactivity is dependent on the intramolecular hydrogen-bonding ability between the ortho substituent and the ether oxygen.
Consequently it was supposed that decreasing the hig her electron density on the ether oxygen in the transition state of the Claisen, rearrangement was related to acceleration of the reaction. And this effect was not observed in acid catalysis or intermolecular hydrogenbonding with the solvent, but was observed especially in intramolecular hydrogen-bonding.

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4- (Di/tri-substituted phenyl) -3, 5-bis (inethoxycarbonyl) -2-isoxazoline 2-oxides [3] were synthesized from di/tri-substituted benzaldehydes and methyl nitroacetate in reasonable yields. The substituents R of [3] inyolve chloro, methoxyl, and methylenedioxy groups (Fig.1and Tables 1, 2).
The ring tran sformation of [3] were executed by promotion of TiC14 in dichloromethane giving either 3 H-indole-3-acetate 1-oxide of type [4] or benzofuro[3, 3 a-d]isoxazole-3, 4dicarboxylate of type [6]/[7]. Di/trimethoxyphenyl derivatives [3e] and [3h] were transformed into 3a, 4-dihydro-5aH-benzofuro[3, 3 a-d]isoxazol-7 (6H) -ones [7e] and [7h] in good yields (Fig.2).
The substituents R strongly affected the course of the reaction such that ipso site-activating group, e. g. [3b], [3e] and [3h] exclusively afforded the respective benzofuro[3, 3 a-d] isoxazoles; whilst the both ortho and ipso sites-activating group such as [3a] and [3c] preferably provided 3 H-indole-3-acetate 1-oxides along with a by-product [8c]. However, ortho site-activating [3d] and [3i] were recovered unexpectedly under the similar reaction conditions (Table 3).

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[N, N'-Disalicylidene-2, 3-dimethyl-2, 3-butanediamine] cobalt (II)/[1b] and [N, N'-bis (3-methoxysalicylidene) -2, 3-dimethyl-2, 3-butanediamine] cobalt(II) [1d] were synthesized and their activity as oxidation catalyst for 2, 6-dialkylphenols was evaluated in comparison with conventional salcomine complexes, [1a] and [1c]. For the O₂-oxidation of 2, 6-dimethylphenol to 2, 6-dimethyl-p-benzoquinone, [1b] and [1d] showed lower activity than [1a]and [1c]. This is attributed to the steric hindrance due to the four methyl groups of [1b] and [1d]. The reaction catalyzed by [1a] ceased before the conversion reached 100 % (e. g., 27% in pyridine, 69% in chloroform +pyridine). On the other hand, the conversion of the reaction catalyzed by [1b] approximated closely to 100% (e. g., 95% in pyridine, 98% in chloroform +pyridine). [1b] and [1d] gave the selectivity (for 2, 6-dimethyl-p-benzoquinone>90%) much higher than [1a] and [1c]. In particular, both the conversion and the selectivity for [1d] in DMF were 100%. The addition of pyridine to [1a] in chloroform slightly enhanced the selectivity (35%>48%) but significantly lowered the conversion (97%>69%). In [1b] in chloroform, in contrast, the selectivity was improved (37%>64%) without lowering the conversion. These results consistently suggest that conventional salcomine complexes are decomposed by activated oxygen species or bases, while tetramethyl-substituted [1b] and [1d] are stable enough to mediate the oxidation in a turnover manner. This is a new method to design stable catalysts using cobalt (II) for oxidation reactions of 2, 6-dialkylphenols.

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Polymers with pendant nitroaryl groups were synthesized by the reaction of poly [(chloromethyl) styrene] and poly (2-chloroethyl vinyl ether) with salts of nitroaryl compounds such as potassium p-nitrophenolate and potassium 4-nitro-1-naphtholate in N, N-dimethylformamide and such nonpolar solvents as benzene and toluene using phase transfer catalysis. When the obtained polymers were irradiated, the nitroaryl groups of the polymers reacted rapidly and these polymers became insoluble in any solvents. This result suggests that these polymers are useful for negative-type photoresists. Therefore, the photochemical reactivity and the practical photosensitivity of these polymers were studied by IR, UV, ¹H-NMR spectra and the gray scale method. From the results obtained, the sensitiv ity was found to depend on the content of the nitroaryl group. In addition, the photocrosslinking mechanism of the polymers was indicated by spectral data of the irradiated polymers.

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The gas phase electrolysis of hydrobromic acid (48 wt%) was experimentally studied for the development of the bromine-based thermochemical hydrogen production processes, by using a fuel-cell-type electrolyzer with graphite felt electrodes and phosphoric acid (85 wt%) electrolyte (Fig.1). The addition of noble metal catalysts to the graphite electrodes improved the electrode performance in the following order: Pt>Pd≈Rh>Ru (Fig.2). The electrode performance depended on both the way for platinum-loading and the amount of platinum loaded on graphite: the electrodes loaded with platinum more than about 0.1 mg/cm2 by an impregnation method exhibited excellent performance (Figs.3 and 4). Both electrolytic current density and the degree of HBr conversion increased with increasing partial pressure of HBr (P_HBr) ; at-P_HBr = 1 5 kPa and at a cell voltage of 0.80 V, the current density and the degree of HBr conversion was 90 mA/cm² and 17%, respectively (Fig.5). The electrode performance scarcely depended on temperature in the range from 398 K to 453 K and the current efficiency was maintained at about 100% (Fig.6). By introducing a reference platinum wire electrode (Fig.8), anodic and cathodic polarization curves were measured. These polarization curves obtained for graphite electrodes revealed that the addition of platinum was effective particularly to reduce the hydrogen overvoltage at the cathode (Fig.9). A continuous operation test at O.80 V proved that a stable current density was obtained for the initial period of about 15 h, and thereafter it tended to drop gradually due to an increase of the cell resistance (Fig.10).

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The temperature dependence of the longitudinal relaxation time (T₁) of proton and phosphorus of flavine mononucleotide (FMN) and flavine-adenine dinucleotide (FAD) was measured. The T₁ minimum of C (9) H of FMN existed at 21°C and that of C (6) H existed at 5°C. The relaxation of C (9) H was interpreted by the effect of C (1') H with Rowan's mechanism and the rotation rate of C (1') H around the C (1') -N (10) axis was estimated to be 4.2 x10¹⁰s^-1 at 80°C.
The T₁ minimum of FC (6) H, FC (7, 8) CH3 of isoalloxazine ring of FAD existed at 32°C and those of AC (8) H and AC (2) H of adenine ring existed at 45.6°C but the T₁ minimum was not observed for FC (9) H and AC (1') H. These facts reveal that FAD rotates with longer correlation time than FMN and FC (9) H relaxes with Rowan's mechanism. It was found that ³¹P of FMN phosphate relaxes with the translation 'mechanism.

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Three manganese compounds, Mn₃O₄, β-MnO(OH) and δ-MnO₂ were prepared by oxidizing amnioniacal alkaline solution of manganese(ll) sulfate with gaseous oxygen at 10°C.
Their formation were identified by X-ray powder diffraction method.
The fine structure of these manganese compounds were obser ved by transmission electron microscops. Three kinds of lattice planes, [211], [220], and [112] were found in Mn₃O₄. Whereas only [001] planes were observable in β-MnO(OH) and δ-MnO₂. Especially in δ-MnO₂, dislocation was recognized.

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The optical resolution by preferential crystallization procedure of pentylammonium salt of N-acetyl-_DL-phenylalanine (_DL-PTA salt) has been studied. It was found by the comparision of the melting point, solubility and infrared spectrum of _DL-PTA salt with those of the _L-salt that _DL-PTA salt is a racemic mixture. The optical resolution of _DL-PTA s alt has been achieved in ethanol at 10 C for the racemic solution with degree of supersaturation of 120%. The _L-PTA salt with optical purity of 95.7% was obtained in the degree of resolution of 98.2%. It was also possible to obtain both of _D- and _L-PTA salts with optical purity of over 90% by successively preferential crystallization. The N-acetyl-_D- and -Lphenylalanine with optical purity of 99.6% was also obtained from the _D- and _L-PTA salts.

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As a basic approarch to the adhesive power of marine proteins, the bonding strength (tensile and compressive shear) of a variety of synthetic poly(amino acid)s on metals has been investigated in water system. High-molecular-weight poly(_L-lysine) hydrobromide was found to have the highest tensile strength (123 kg/cm²) on iron, while gelatin the highest compressive shear strength (21 kg/cm²) on Al₂O₃. High-molecular-weight water-soluble poly(amino acid)s, which contain lysyl residues and are random-coil conformation, are effective for the adhesion on metals. Poly(glutamic acid) and poly(cysteine) are little effective adhesion on metals.
The results of the bonding strength of poly(amino acid)s in organic solvents were also described. Poly(_DL-methionine) in dichloromethane is most adhesive on metals. !

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ESR observations were carried out for the seed pearls obtained from Uwa Sea in Ehime prefecture. The seed pearls used for ESR observation were classified in several groups on the basis of their different appearance and, color. The satin white and the pale yellow seed pearls revealed ESR hyperfine structure typical to manganese(II) ion doped into the aragonite matrix in calification phase of biominerals. On the other hand, however, the pearls contaning the blackish materials gave ESR signal of an organic free radical assignable to that contained in melanin, as justified from the isotopic g-factor (g), line width(8) (g=2.0045 and δ=0.8mT), and the microwave saturation behaviour. In this case, the observed hyperfine structre of manganese(II) was found to be much similar to that of manganese (II) doped in calcite rather than that in aragonite matrix. With increasing the ESR intensity of organic free radical (spin/g), the ESR of manganese(II) showed a concomitant decrease in the apparent signal intensity. This suggests that the accumulation of melanin-like free radical in the prismatic pearl layer would be one of the important mechanism to explain the blackish color change occurring in the pearl during the cultivation.

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Asymmetric reduction of acetopherione by optically active hydride reagents prepared from lithium aluminum hydride and (S)-poly[(S)-iminoethylene]s or the corresponding (S)diamine analogs, yielded optically active 1-phenylethanol. When (S)-diamines were used as modifier, all the sign of the optical rotations for the products was the same, (R)-1-phenylethanol was predominantly formed. On the other hand, for (S)-copolymers as modifier, the configuration of the products was influenced by the molar composition of each polymer.

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Sulfuric acid particles in the atmosphere were collected on a teflon filter. The teflon filter was placed in a teflon-stoppered test tube and 10 ml of acetone was added to extract the particles. A 30 μl of diazomethane-ether solution was added to the sample so: ution. The test tube was shaken and made to stand for 30 min. Sulfuric acid was methylated with diazomethane at room temperat ure to dimethyl sulfate and determined by a gas chromatograph with a flame 'photometric detector.
Diethyl sulfate was used as an internal stan dard for the determination of dimethyl sulfate. The detection limit of sulfuric acid particles by the proposed method was 0.1 μg/m³ in 5 m³ air. The present method was applied to the determination of sulfuric acid particles in the atmosphere at Setagaya-ku and Chiyoda-ku in Tokyo in December 1984 and JuneJuly 1985. The concentration of sulfuric acid particles, was found to be 0.2-1.2 μg/m³ and the value of [H₂SO₄]/[SO₄^2-] was 0.02-0.12.

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