Solid reactions between aluminium oxide and zinc oxide have been studied on equimolar mixtures of both reactants in powdery form and on those with either one of the reactants in granular form. The rate of reactions for the mixtures of granule and powder was about one tenth of that for the mixtures of powders. Jander's equation was applicable to the reactions of both of these mixtures. Apparent activation energies were high for the reactions of mixtures of powders and were about 340 kJ/mol, and those for the reactions of mixtures with granules were as low as 160 to 200 kJ/mol. In the reaction system where aluminium oxide granules were filled in a cylindrical container of zinc oxide, the number of contact points between the reactants was small and the parabolic law was applicable which gave a low apparent activation energy of 154 kJ/mol. SEM observations suggest that the diffusion of ZnO²⁺ through the solid product layer is rate determining in the powder mixtures and the diffusion of ZnO vapor through the gas phase in pores is the rate determining step for the reactions of the mixtures with granules.

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The isobutene hydration rates under a constant isobutene pressure increased monotonously with the addition of tetrahydrofuran (THF) at a THF/12-molybdophosphoric acid (PMo₁₂)molar ratio below 4-6 (Fig.1). The increase in the hydration rates with the addition of a relatively small quantity of THF can be ascribed to an increase in isobutene solubility (Fig.1). Further addition of THF resulted in a levelling-off or a decrease in the hydration rates in spite of the increase in isobutene solubility (Fig.1). Other oxygen-containing substrates such as t-butyl alcohol (TBA), isopropyl alcohol (IPA), acetone etc. had similar effects in the hydration rates (Fig.2). The presence of a large quantity of THF drastically depressed the hydration rates (Fig.3). This can be chiefly attributed to a decrease in acidity of heteropoly acid in mixed aqueous solvents (Fig.4). In the case of presence of a large quantity of oxygen-containing substrates, heteropoly anions were found not to contribute the increase in the hydration rates (Figs.5, 6). Therefore, a large quantity of an oxygen-containing substrate is considered to inhibit the interaction of heteropoly anion with isobutene molecule and also to lead to the decrease in the isobutene hydration rates.

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The isobutene hydration rates were found to decrease linearly with increasing the degree of reduction of heteropoly acids in concentrated aqueous solutions (Fig.2). On the other hand, the reactions in reduced heteropoly acid solutions were found to be of second order in terms of proton concentration as well as in unreduced heteropoly acid solutions(Fig.1). Therefore, the isobutene hydration in concentrated reduced heteropoly acid solutions is suggested to proceed through the similar mechanism to that in unreduced heteropoly acid solutions. The decrease in the hydration rates due to the reduction of heteropoly acids is associated with a decrease in isobutene solubility (Fig.3). Acidity of four-electron-reduced 12-moly bdophosphoric acid (PMo₁₂) was measured by using NMR. The decrease in the acidity of the reduced heteropoly acid was clarified to be small enough not to depress the activity in the isobutene hydration (Fig.4). By comparison of isobutene hydration rates in various degrees of reduced heteropoly acid solutions with different contents of β-type heteropoly acids, no difference in the activity between α-PMo₁₂ and β-PMo₁₂ was observed (Fig.2).

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The effects of some reaction conditions on the autoxidation of 2, 6-dimethylnaphthalene catalyzed by cobalt-manganese-bromide ions in acetic acid were studied at temperatures of 65 to 200°C. The oxidation of each methyl substituent proceeded one after another to carboxylic acid via aldehyde by successive reaction (Figs.3, 4). The conversion of substrate was remarkably decreased with increasing substrate concentration (Figs.1, 2), suggesting that the presence of naphthalene ring retarded the oxidation reaction. It was also observed that the rate of oxidation was gradually decreased as the bromide, ion was converted to the inactive form of organic bromide (Fig.7). Although methyl substituents on naphthalene ring can be oxidized faster tian those on benzene ring (Figs.5, 6), the overall oxidation of 2, 6-dimethylnaphthalene proceeded rather slowly at 90°C, because of some retardation effects above mentioned and low solubility, of folmylnaphthoic acid in acetic acid. However, the oxidation of substrate to 2, 6-naphthalenedicarboxylic acid proceeded smoothly at 150°C under oxygen pressure of 10 bar, restating in a good yield as high as 85% (Table 5).

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From a point of view of an application to an oxide ion conducting solid electrolyte, the chemical stability at a high temperature in the air of the neodymium yttrium fluoride oxide in composition of Y₂Nd₂F₆0₃ was studied. Up to about 700°C, Y₂Nd₂F₆0₃ with the tetragonal structure was proved to be chemically stable and to keep a high oxide ion conductivity in the order of 10^-2S.cm^-1 at 650°C (Figs.1, 2 and 9). Above 1000°C, Y₂Nd₂F₆0₃ was gradually converted into YNdO₃ due to the pyrolytic hydrolysis through a intermediate stable compound with composition of YNdF₂O₂ with the rhombohedral structure (Fig.2 and Table 1). Resulting from the high temperature X-ray diffraction, the tetragonal Y₂Nd₂F₆O₃ and the rhombohedral YNdF₂O₂ were found to be transformed into the cubic above 800 and 500°C, respectively (Figs.5, 7 and 8). Both transformations were reversible and their enthalpies were measured to be about 4.5 kJ-mol^-1 by the differential thermal analysis. The kinetic of the hydrolysis was expre ssed by Jander's equation, [1-(1-x)^1/3]²=kt (Fig.3). The electrical conductivity of Y₂Nd₂F₆0₃ la rgely decreased with decrease of the fluorine content due to the hydrolysis (Fig.9). As an additive to elevate the therma l stability without decrease of the electrical conductivity, In₂O₃ and V₂O₅ were found to be effective (Table 2).

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An encapsulation process of magnetic metal powders was investigated for the purpose of manufacturing powder cores. Fe-1%Si alloy powders were immersed and stirred in sol containing metal alkoxide polymer or derivatives. Surplus sol was filtered and powders were dried at 150-170°C for 30 min. Through the proposed process, individual alloy particles were uniformly encapsulated with a thin film. According to SEM observation of the capsule surface, the thicker film part had fine cracks and the concave areas had coarse cracks. The obtained capsuled powders were compacted at 800 MPa pressu re to yield powder cores. Densities of these cores were about the same as that of a core made of bare powders. Magnetic measurements of these cores revealed that the permeability was not decreased, even in a high frequency range. This result shows that the coating film is not exfoliated by the friction force during the compaction and insulates the metal particles. It is also shown that the cracks do not deteriorate the insulation. This encapsulation process is considered to be useful to obtain powder cores which have both high induction and good frequency characteristic. Furthermore, the core manufacturing technique has the following advantageous points.1) Sol-gel process gives a thin uniform film and the magnetic gap between the metal particles is kept small.2) The high temperature, which causes the change of the magnetic property of metal itself, is not necessary for the film formation.3) The encapsulation can be achieved in large amounts by one batch.4) These cores have better durability to high temperature than a core made by a conventional organic insulator method.

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9-(2-Dimethylaminophenyl)fluorene [2], 9-acyl-9-(2-dimethylaminophenyl)fluorene ([4]and [5]) were prepared from 9-(2-dimethylaminopheny1)-9-fluorenol [1], and the conformational equilibria (ap_??_sp) of these fluorene derivatives were investigated by their ¹H-NMR spectra measured in CDCl₃. The equilibria of these compounds leaned to the sp-form. Compound [1] formed an intramolecular hydrogen bond between the amino nitrogen and 9-hydroxyl group to favor the sp-form. By the addition of trifluoroacetic acid into the CDCl₃ solution of [2], trifluoroacetate salt of [2] was formed and the predominant conformer was changed to the ap-form of the salt. Stability of the ap salt could be ascribed to an N-H...π interaction.

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Reduction of N-butyl-N-(2, 2, 3, 3-tetrafluoropropyl)butanamide, as a model compound of polyfluorinated amides, was investigated using various reducing reagents, and it was found that a combined reagent of NaBH₄ with AlCl₃ gave the best result. Various N, N-disubstituted amides containing polyfluoroalkyl groups were also reduced with this reagent to afford the corresponding polyfluorinated amines in good yields (75-90%). N-Monosubstituted and N-unsubstituted amides containing polyfluoroalkyl groups at the site of the nitrogen or the acyl, carbon atom were reduced with this reducing reagent to give the corresponding polyfluorinated amines, respectively.

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The reaction of several 2, 2-dichlorospiro[cyclopropane-1, 9'-fluorene] derivatives (2, 2dichloro-(3-methyl- [1a], 3-ethyl- [1b], 3-isopropyl- [1c], 3-benzyl- [1d], 3-diphenylmethyl-[1e], 3-(1-phenylethyl)- [1f], 3, 3-dimethyl- [1g], and 3-methyl-3-phenyl-)-spiro[cyclopropane-1, 9'-fluorene] [1h]) with n-Bu₃SnH afforded ring-opening compounds, 9-(1-chloroethenyl)fluorene derivatives [2], and/or cyclobutane compounds, 2-alkylidene-3(9-fluorenylidene)spiro[cyclobutane-1, 9'-fluorene] derivatives [3]. It was concluded that compounds [3] were produced by the cyclodimerization of allenes, which were form ed from [2], in a head-to-tail manner. In the cases of [1a], [1c], and [1g] both the products [2] and [3] were obtained. Only [2] was derived from [1e], [1f], and [1h], and this was ascribed to the large steric hindrance in the cyclodimerization of allenes. From [1b] and [1d] only [3] was obtained. The stereochemistry of [2] and [3] were also discussed.

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The reactions of benzamidoxime with benzonitrile or acetonitrile did not occur under ordinary pressure, but they proceeded smoothly under several handred MPa pressure to give 3, 5-diphenyl- or 3-phenyl-5-methyl-1, 2, 4-oxadiazoles, [1a, b], respectively. The pressure effect on these reactions were surveyed and their activation volumes (ΔV^≠) were estimated to be -14.6 and 18.5 ml.mol^-1, respectively. Upon treatment with disubstituted cyanamides, amidoximes gave 5-amino-1, 2, 4-oxadiazoles, [3] together with a small amount of the corresponding 5-diaminomethyleneamino compounds, [4], while [4] were obtained as main products when the above reactions were carried out under 400 MPa pressure. It was thus found that the reactions of amidoximes with nitriles and disubstituted cyanamides are significantly promoted under pressure to afford a number of novel 1, 2, 4oxadiazole compounds.

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The pyrolysis products of bromotrifluoromethane in the presence of nitrogen, steam and/or hydrogen at 675-855°C have been investigated. The pyrolysis was carried out by a flow method under atmospheric pressure using a spheric quartz reactor. When the reacta nts were diluted with nitrogen, the products were hexafluoroethane and bromine (Table 1). On the other hand, when steam was used as the diluent, the products were trifluoromethane, hexafluoroethane, bromine and small amounts of tetrafluoroethene and carbon dioxide (Table 1). When hydrogen was added to the diluents, the major products were trifluorometh ane and hydrogen bromide, and bromodifluoromethane, tetrafluoroethene, hexafluoroethane and a few other fluorocompounds were formed as the minor products (Table 2). The effects of nitrogen and steam on the conversion rates of bromotrifluoromethane were nearly identical. The conversion rates increased with addition of hydrogen. The formation m echanisms for these fluorine containing major products were discussed.

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An ion sensitive field effect transistor (ISFET) type _L-glutamate sensor was studied using an immobilized thermophilic enzyme glutamine synthetase from a moderate thermophilic bacterium. The ISFET glutamate sensor, on which the glutamine synthetase and albumin were immobilized by glutaraldehyde, was able to determine the _L-glutamate concentration in the range of 0.5-400 mmol.dm^-3. The response time of the glutamate sensor was about 3 min. The selectivity of the glutamate sensor was studied by measuring its responses to various amino acids, and. the sensor did not respond to any other amino acids except _D-glutamate and α-methylglutamate. Therefore, the glutamate sensor was found to have high selectivity for _L-glutamate. The sensor also revealed high reproducibility. The coefficient of variation of the sensor was determined to be 9.3% for 10 samples containing 10 mmol.dm^-3 _L-glutamate. The initial output voltage of the glutamate sensor was retained for 15 d. However, the output voltage decreased to about 45% of the initial output voltage after 30 d.

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The treatment of mild steels by chemical conversion was studied using 10 kinds of aqueous molybdate solutions under various conditions, pH of which was from 2 to 12. Chemical conversion coatings were formed in the range of pH 2 to 6 and at the temperature from 25 to 80°C. An addition of phosphoric acid into the solutions to adjust pH gave more uniform and denser coatings. It was also found that the addition of an oxidizing agent, such as nitrate or nitrite, lead to a better result. An X-ray diffraction test indicated that the chemical conversion coating obtained in this new process was amorphous, and IR spectroscopy and Auger electron spectroscopy tests revealed it as FeMoO₄ or a mixtu re of FeMoO₄ and Fe₃(PO₄)₂. The corrosion resistance of the painted steels after the conversion treatment was examined by a neutral salt spray test. It was confirmed that, among various aqueous molybdate solutions, the highest corrosion resistance was obtained from a sodium molybdate solution containing phosphoric acid or a mixture of phosphoric acid and oxidizing agent.

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Macromolecular complex (MC) consisting of “polyaluminium chloride” (PAC) and poly(potassium vinyl sulfate) (PVSK) was prepared by dropping PAC to PVSK solution at pH 1.0, and a membrane was casted from 1, 4-dioxane-hydrochloric acid solution to obtain a stable MC membrane against acid and alkaline solutions. The transport ratio of Na+and the electric potential difference between left and right sides of the membrane were measured. As the results, the transport ratio was high when the electric potential difference was large and was maintained for a long time. From the result, it was revealed that the driving force of transport depends on the membrane potential such as a Donnan potential and diffusion potential between both sides of the membrane. The membrane potential difference was decreased rapidly by Cl^- permeation from the acid side to the alkaline side. In addition, the transport ratio of Na⁺ and the membrane potential difference were also measured in the case that poly(styrenesulfonate) ion was used as a counter ion and compared with those in the case of HCl. On the other hand, K⁺ was transport more rapidly than Na⁺ in the selective transport. The selective transport was controlled by the radius of hydrated alkali metal ions and the affinity of carrier in the membrane for those ions. The MC membrane consisting of PAC as inorganic macromolecule and PVSK was compared with that constituted of glycol chitosan as organic macromolecule and PVSK for the differences of characteristics.

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Crystal shapes of CaS: Ce prepared from CaSO₄2H₂0: Ce have been studied. CaSO₄2H₂0 as a starting material was obtained by precipitation in CaCl_2-H₂SO₄(Ce)_-H₂0 (H) or CaCl_2-Na₂SO₄(Ce)_-H₂0 (N) system. The crystals of the resulting CaSO₄2H₂0: Ce were all needle-shaped. The length of the crystals was in a range of 5-15 μm for the H system, and was a few micrometers to 10 μm for the N system. CaSO₄: Ce (II-CaSO₄: Ce) was obtained by dehydrating CaSO₄2H₂0: Ce at 700°C without forming calcium oxide. II-CaSO₄: Ce obtained from the H system maintained the needle like form, while the sulfate obtained from the N system changed from its original needle like form to a granular one CaS: Ce was prepared by hydrogen re duction of II-CaSO₄: Ce at 900°C. The reduction did not affect the crystal shape of the resulting sulfide. Sodium ions incorporated in CaSO4.2H20: Ce seem to render the crystals granular.

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Various kinds of Leuco triphenylmethane derivatives [2a-n] having no substituents either on A or B ring were prepared by the condensation of aromatic ketones with substit u ted benzenes or by Grinard reactions of aromatic ketones with corresponding Grignard reagents. The Leuco dyes[2] turn into colored cations[3] in an acidic medium. UV-VIS spectra of those dyes in acetic acid and sulfuric acid were measured and discussed in terms of the effects of substituent R for the ring C and bridging group X. A good correlationshi p between λ_max of the xanthene derivatives and the Hammett's σ. value of the substituents was observed, and furthermore, the effect of the bridging group X of [2] on t he longest λ_max was that the bathochromic shift increased as the electron donating ability of the bridging group X decreased except for X=S. The effects of these substituent R a n d bridging group X are very similar to those of the substituent on Y band in triphenylmethane dyes having substituents on ring A and B.

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A comparison of the rate constants (k_obs) of the chemical reactions which occure after the electrochemical oxidation of chlorpromazine (CPZ) to CPZ cation radical (CPZ) in various supporting electrolyte solutions was made. In solutions containing bivalent anions (such as phosphate, sttccinate and glutarate solutions)the k_obs's obtained by rotating disk voltammetry were larger than those in solutions containing monovalent anions (like an acetate solution). The rate constant depended on the structure of the anion.

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The Schiff's bases derived from t-butylamine and 2-methylcycloalkanones of ring sizes 5-7 react with methyl propiolate to give the corresponding Michael adducts. The accep tor is introduced selectively at the more highly substituted position. The adducts s e rve as precursors of methyl-substituted Octanedioic, nonanedioic, and decanedioic acids.

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Several flavonoids were isolated from the leaves of Polygonum filiforme var. neofiliforme, flaccidum, P. Blumei, P. Y o kusaianum, and P. senticosum. Their structures we re identified as myricetin 3-rhamnoside, quercetin 3-(2-O-galloylrhamnoside), quercetin 3-rutinoside, quercetin 3-rhamnoside, kaempferol 3-glucoside, isorhamnetin, quercetin, and apigenin 7(glucuronide 6-methyl ester) by the comparison of their TLC, HPLC, and spectroscopic data with those of the authentic samples. It was clarified that quercetin 3-(2-O-galloylrhamnoside)is distributed in P. filiforme var. neofiliforme and P. flaccidum.

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Yearly evaluation of air quality was carried out by applying the pollution index (AQI), which was proposed in a previous work, to Kanagawa Prefecture. It was found that the frequencies (d/d%) of “Polluted” level (the ambient air is polluted beyond the air quality standards) gradually decreased between 1979.4 and 1985.3. The frequencies of “Clean”level (the pollutants in the air are of a half of air quality standards) gradually increased. The major reason is that O_x concentration decreased in the suburban area. NO₂ concentration also slightly decreased, but the contribution to pollution relatively increased. The appearance of “Polluted” level was about 10-30% (d/d%) in Kanagawa Prefecture in 1985. The AQI index is thus useful in long term evaluations of air quality as well as short term evaluation like daily evaluation.

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