Good proton conducting solids usuable at high temperature are applicable to a solid electrolyte for high electrolytic current devices like a fuel cell, an electrolyser for hydrogen production, a hydrogen separator etc. as well as for a high temperature-type chemical sensor. Such materials had been scarcely known until we found a series of oxide ceramics which have appreciable protonic conduction under hydrogen-containing stmosphere at high temprature. They are perovskite-type oxides based on SrCe03 or BaCeO3 in which some trivalent cations are partially substituted for cerium. belong to this class of conductors. Later, some zirconate-base sintered oxides were also confirmed to be proton conductors under hydrogen containg atmosphere at high temperature. These oxide ceramics exhibit p-type electronic conduction in an atmosphere free from hydrogen or water vapor. However, when water vapor or hydrogen is introduced to the atmosphere at high temperature, electronic conductivity decreases and protonic conduction appears. When the ceramics are exposed to the hydrogen gas, they become almost pure protonic conductors, the conductivities of which are multi 10-2 S cm' at 1000 °C and multi 10-3 S cm-' at 600 °C. Protonic conduction in these solids could be verified by mean s of electrochemical permeation of hydrogen across the ceramics. These oxides are unique ionic conductors in respect that they have no host constituents which liberate conducting ion (proton). Using these ceramics as a solid electrolyte, several types of electrochemical devices have been demonstrated by way of experiment. Based on the principle of hydrogen concentration cell, hydrogen sensors have put to practical use for molten aluminum in casting process.

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The grafting of polymers onto carbon black by the reaction of reactive groups introduced onto the surface with functional polymers having terminal hydroxyl or amino groups was investigated. Surface carboxyl and phenolic hydroxyl groups present on carbon black were found to be able to covert into chloroformyl, azidocarbonyl, isocyanato, blocked isocyanato, 2, 4-dichlorotriazinyl ether, epoxide, phthalic anhydride, 1-imidazolylcarbonyl, pentachlorophenyl ester, and p-nitrophenyl ester moieties. Although isocyanato groups introduced onto carbon black were readily deactivated even if it was stored in vacuo, the content of other reactive functional groups scarcely decreased when these carbon blacks were stored in vacuo. It was found that by the heating of carbon black having these functional groups with functional polymers, such as polypropylene glycol (PPG), polyethylene glycol, and poly( iminoethylene), the corresponding polymers were grafted onto the surface: the percentage of grafting was determined to be 15-60%. On the contrary, when untreated carbon black was heated with these polymers, the grafting of polymers onto the surface was hardly observed. Furthermore, these polymers grafted onto carbon black surface were readily removed from the surface by the hydrolysis with alkali. Based on the above results, it was concluded that these founctional polymers are grafted onto carbon black surface with chemical bonds, such as ester, amide, and urethane bonds. The percentage of polymer grafting onto carbon bl ack increased with increasing molecular weight of functional polymers, but the number of grafted polymer chain decreased. It was found that the relationship between the number of grafted chain (G) and molecular weight (M ) of founctional polymers is given by the following equation (K and a are constan ts): 0, 1=K x/17/Polymer-grafted carbon black gave a stable co lloidal dispersion in a good solvent for grafted polymer, but immediately precipitated in a non-solvent.1023

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In order to reveal the reactivity of thiols, the hydrogen-isotope exchange reaction (liquidsolid reaction) between one of thiols dissolved in p-xylene and poly(vinyl alcohol) labeled with tritium was observed at 50-90°C. The rate constants for the thiol have been obtained with both the A"-McKay plot method and data obtained. Several for other thiols have been obtained with the same method as above. Comparing these (and obtained previously) with each other, the following seven matters have been clarified. ( 1 ) The reactivity of benzenethiol increases with temperature. (2) Both the reactivity of benzenethiol and the temperature dependence of the reactivity is similar to that of phenol (and benzoic acid). ( 3 ) Benzenethiol is more reactive than cyclohexanethiol and 1-he xanethiol. (4) The reactivity of a certain aliphatic thiol changes with both the length of the straight-chain alkyl group in it and its isomerism. ( 5 ) It seems that the reactivity of aliphatic (or alicyclic) thiols follows the Taft's equation. (6) The reactivity of aliphatic (and alicyclic) thiols can be enhanced with one of the substituents (which have the electron attractive effect) since the gradient of the straight line (in the plot based on the Taft's equation) for these thiols in the reaction is greater than zero. (7) It can be assumed that the effect of the polar effect on the reactivity of the aliphatic compounds is larger than the effect of the steric one on that.

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Zinc oxide catalysts were prepared from zinc chloride, sulfate, and nitrate and diethyl zinc by several methods and subjected to acid property measurement, X-ray diffraction, DTA, TG, and chemical analysis. The catalysts were prepared by thermal decomposition of hydrolysis products which had been precipitated by ( 1 ) dropwise addition of ammonia water to zinc salt solution (method I), (2) dropwise addition of salt solution to ammonia water (method II), ( 3 ) the homogeneous precipitation method (method HP), or ( 4 ) the continuous flow method (method CF) diethyl zinc was hydorolysed by ( 5 ) dropwise addition of its hexane solution to water. The chemical analysis and x-ray diffraction showed that the hydrolysis products were mainly Zn5(OH)5C12 (from the chloride by methods I, II, and CF), Zn4(OH)6(SO4) H 20 (from the sulfate by method I), Zn5(OH)9(NO3)22 H20 (from the nitrate by method I), and Zn4(OH)6(CO3) H20 (from the chloride by method HP). Every catalyst prepared from the zinc salts was shown to contain a substantial amount of the corresponding anion and to exhibit a strong acidity of 3.3<H01.5. Especially, the catalysts prepared from the chloride according to method I contained 1.6 mmol of the salt enough to explain its anomolously large acidity as much as 2.1 mmol g-1. The catalyst prepared from diethyl zinc, however, was free from the anions and showed a weak acidity of 0.01 mmol g (3.3&lt; H04.0).

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Preparation of sodium tungsten bronze (Na., W03: 0.4. ≤ x≤ 1, cubic) by the reduction of Na2W207 or Na., W, Ois with hydrogen was studied by gravimetry, X-ray diffraction analysi s and SEM observation. A hydrogen flowing system reactor was used and effects of temperature and hydrogen concentration on the solid products were examined. In the case of the reductuon of Na2W2O7; For hydrogen concentration with more than 50 vol%, excessive reduction took place even below 550 °C and unfavorable products, metallic tungsten and 9-tungsten (W30), were observed. On the other hand, for hydrogen concentration with les s than 20vol%, the extent of the reduction was easily controlled above 625°C and only two phases (NasWO, (cube-like crystals, the size: 5-20 pm) and Na.2W04) were observed as solid products, where x value (0.75< x< 0.90) was found to be mainly dependent on hydrogen concentration. Crystal growth with cube-like shape above 625 °C was considered to be attributable to the liquid phase related process since the eutectic point of the Na2W04-Na2W207system is 622 °C. In the case of the reduction of Na.2W4013; Productions of metallic tungsten, Na2W207 and Na2W6019 were observed. However, for temperature and hydrogen c oncentration with (675 ° C, 5 vol%) or (650 ° C, 10 vol%), final product was mostly single phase of NazW03 (x 0.50).

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Peroxopolytungstic acid (W-IPA) is a promising inorganic resist material formed by a direct reaction of metallic tungsten and hydrogen peroxide. Thin films about O.5 pm thick were formed on silicon wafer or glass substrate by conventional spin coating technique using its 50 wt% aqueous solution. Its structural change during UV irradiation, which makes the films insoluble in water, was evaluated by IR, Raman and RDF (radial distribution function)and compared to that brought about by heat treatment. Infrared and Raman spectroscopy revealed that an edge-sharing arrangement of the WOG octahedra (or W07 pseudo-octahedra)in W-IPA disappeared after heating it over 100 °C, while the structure remained substantially unchanged when it was heated at 80 °C for as long as 8 h. Such an edge-sharing arangement was also destroyed by UV-irradiation up to 4.5 J cm-2. After irradiation, W-IPA film was changed into a dense structure built up of corner-sharing WOG octahera, which was generated by the condensation of polyaninons accompanied with the decomposition of their peroxo ligands. The resultant oxygen molecules were caged in such a network structure at least partly and retained until structural rearrangement or crystallization.

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The determination of hydroxyl radical (-OH), which was generated by the Haber-Weiss reaction of hydrogen peroxide using bis(ethylenediamine)copper(II) sulfate([Cu(en)₂]SO₄)as a catalyst, was investigated by the thiobarbituric acid (TBA) method spectrophotometrically. The determination of OH is carried out as follows: take 0.2 cma of 0.38 mM [Cu(en)2]2+ solution, 0.9 cm3 of pH 7.4 buffer solution, and 0.5 cm' of 45 mM 2-deoxy- Dribose solution in the test tube of about 30 cm3, and further add 0.2 cm3 of the same buffer solution (in the case of studing the inhibitor of OH reaction, the sample solution is added instead of the buffer solution) and 0.2 cm3 of 11202 solution (concentration, <0.1 mM); after incubating this solution for 5 h at 40 °C, add 12 cm3 of about 70 mM TBA and make to 15 cm3 the total volume by adding 1 cm3 of about 2 M HC1 to adjust the pH below 2.5; put this solution in boiling water for 30 min and after standing for 1 h at 25 °C, measure the absorbance at the wavelength of 532 n m.1, 1, 3, 3-Tetramethoxypropane was used as the standard substance of OH determination. This procedure can be applied to the research of the catalysis of metal complexes which allows to generate OH from 1-1202.

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The complexes of iron(III) with L-tartaric acid (hereafter abbreviated as iron(M)-tartrate complexes) formed in aqueous solutions at various pH values are extracted with (methyl)trioctylammonium chloride (TOMAC; R3R'NC1) in toluene. The complex species before and after extraction have been characterized by various techniques. A magnetic susceptibility titration experiment has shown that iron(III)-tartrate complexes in aqueous solution vary in structure accoriding to the conditions of pH and R=[L-tartaric acid]/[iron(III) ion] and are extracted with TOMAC into toluene from aqueous solution without great changes in structure. The complex species at R=1 (pH 6-12), R=3 (pH 3-12) and R=10 (pH 3-8)are of a type of iron(III) cluster complexes. It has been revealed that in aqueous solutions at R=3-10 the ratio of tartrate anion to iron(III) ion in the complexes are less than 2 and that this ratio decreases with an increase in pH. The estimated compositions of extracted complexes at R=3 (tart=tartrate anion) are as follows It is reasonably considered that the complex species at R=3 (pH10) bear a structural resemblance to ironan hydroxide clusters whose surfaces are modified with tartrate anions. Those negatively-charged carboxyl groups projecting to the outside can make ion-pairs with TOMAC cations and the complex species are extracted in toluene in such a form as reversed micelle. These complexes may be less than several tens Å in diameter.

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Tubulous aggregates were partially formed when bis[4-(3-decylureido)phenyl]methane (DUDM) crystals were heated in paraffinic mineral oil (PMO) at 160 °C for 2 h. Pulverizing the crystals before heating increased the amount of the tubulous aggregates. As the pulverization proceeded, the initial plate-like crystals(C) turned to granular shape, and the surface area changed from 6.9(C) to 10.1 (stage C-1) and finally to 7.9 m2/g (stage C-2). Lowering fo crystallinity for the C-2 was observed in XRD patterns. Considering the two factors (surface area, crystallinity), p ulverization would make easier to insert the PMO into two kinds of inter-layers in crystals, and to form tape-like aggregates which change helically into tubulous aggregates.

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(6 R)-6-(1, 3-Benzodithiol-2-yloxy)-3, 5-cyclovitamin D3 (6 a) was prepared from (6 R)-6hydroxy-3, 5-cyclovitamin D3 ( 5 ) and 1, 3-benzodithiolylium tetrafluoroborate. Allylic oxidation of 6 a yielded (6 R)-1 a-hydroxy-6-(1, 3-benzodithiol-2-yloxy)-3, 5-cyclovitamin D3 (6 b)(49% yield from 5). Compound 6 b was hydrolyzed with 12-phosphomolybdic acid catalyst to give 1 a-hydroxyvitamin D3 (1 b) (mp 137-138 °C, isolated in 33% yield). In the cycloreversion of 6 b bearing 6-[(R)-1, 3-benzodithio1-2-yloxyl] group, no 5, 6-trans isomer ( 4 )was given in contrast with that of (6 R)-1a-hydroxy-6-methoxy, -3, 5-cyclovitamin D3 (3 b). Similarly, the acetolysis of 6 b gave only 1 a-hydroxyvitamin D3 3-acetate ( 7 ) (46%yield) without forming the 5, 6-trans isomer ( 8 ). In our method, 1 b (or 7) can be easily isolated and purified because of the absence of 5, 6-trans isomer in the reaction mixtures. Therefore, a large scale synthesis can easily be carried out.

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The three kinds of chloro-substituted aromatic polyamides (PC1P-BEA, PC1P-TA, and PC1P-C1TA) were prepared by low-temperature solution polycondensation of chloro-pphenylenediamine with bis[4-(chloroformyl)phenyl] ether, terephthaloyl dichloride, chloroterphthaloyl dichloride. The convers ion of these aramids into the corresponding polybenzoxaboles by heat-treatmet is investigated by CHN elemental analysis, pyrolysis/gas chromatography/mass spectrometry, dnynamic viscoelastic properties, IR spectroscopy, and UV spectroscopy. The summarized data of PC1P-BEA are the follows ( 1 ) Untreated PC1P-BEA was dissolved i n N, N-dimethylacetamide and N-methy1-2pyrrolidone, but PC1P-BEA treated at 250 °C was insoluble in those solvents. ( 2 ) The value of dynamic storange modulus E' of 2-fold-drawn PC1P-BEA film was decreased in the range from room temp. to around 250 C and increased in the range from around 250 to 380 °C. ( 3 ) In the pyro lysis products of PC1P-BEA, there is a peak in the chromatogram for a compound with mfe-=.195 attributed to 2-phenylbenzoxazole. ( 4 ) The values of CHN elemental percentage compositions of PC1P-BEA treated at 450 °C for 30 min were similar to those calculated from constitutional repeating unit of the corresponding polybenzoxazole. ( 5 ) In the IR spectra of PC1P-BEA treated at 450 °C, the absorptions at 3400 (NH), 1630 (vc=0), 1370 and 1290 (pc-N and Oc_N) cm-1 decreased with an increase in time of treatment. ( 6 ) In the UV spectra of PC1P-BEA treated from 380 to 450 °C, the absorption peak near 300 nm was shifted toward the long wavelength region with an increase in temperature. The data of PCP-TA and PC1P-C1TA shows the same tendencies as those of PC1P-BEA. The above data show that PC1P-BEA, PC1P-TA, and PC-C1TA were slowl y converted into the corresponding polybenzoxazols by heat-treatment at temperatures of around 250 °C and above.

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The thermal polymerization of dihydrohydroxy-exo-dicyclopentadienyl and tetrahydrohydroxyexo-dicyclopentadienyl maleates was carried out at 220 °C in the absence of any initiator to investigate quantitatively the mechanism of polymer formation. The characteristics of the thermal polymerization were discussed mainly with regared to the average molecular weight, molecular weight distribution, and spectra of the products before and after hydrolysis. It seems that the presence of a double bond within the skeleton of dicyclopentadiene is necessary for the thermal polymerization to occur. This thermal polymerization is initiated by both radical chain reaction of the isomerized fumaroyl double bond and ene-reaction of the fumaroyl double bond with the allylic double bond in the cyclopentene ring. The radical chain reaction terminated rapidly at a degree of polymerization less than 6. On the other hand, the ene-reaction trends to progress with increasing molecular weight of the polymer produced.

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Polyether polyol prepared by polymerization of propylene oxide with alkaline metal catalyst contains some by-products such as terminal unsaturation compounds, polypropylene glycol and dioxan derivative. The molecular weight distribution becomes broader as polymerization proceeds, because of such by-products. Author investigated the r elation between refining processes and molecular weight distribution of the crude polyether polyol, and confirmed that the combination of migration by heat treatment, acid hydrolysis and rinsing with hot water gave narrow molecular weight distribution. And also, concentration of terminal unsaturation compounds decreases to be nearly zero with those treatments.

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On the synthesis of aluminum hydroxide from aluminum salt solution by homogeneous precipitation method using urea, the initial prcipitation behavior of aluminum hydroxide in the presence of sulfate ion was investigated. It was observed that the growth of aluminum hydroxide particles occurred discretely up to ca.80 nm in diameter, but above this size the growth occurred by accompanying the particle coalescence in the course of the precipitation of aluminum hydroxide. This agrees with the previous observation.

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The optimum conditions for silica coating on carbon materials by using an ethanol solution of tetraethoxysilane (TEOS) were studied. A homogeneous film of silica with a thickness of 0.2 pm without any cracks was obtained by dip-coating process under the following conditions; the ethanol solution containing TEOS of 0.1 molg, the pulling-out velocity of the carbon substrates at 2.0 cm/s, the gelation in the air for 48 h, and the heating at 70 °C for 1 h and then up to 1000 °C by 5 °C/min. From the SEM observation of the cross-section of the substrates with silica, it was shown that the silica coating film adhered excellently to carbon substrate.

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A cationic palladium(II) complex [Pd(CH₃CN)₂(PPh₃)₂](BF₄)₂ catalyzed the formation of amides by additon of tertiary alcohols to nitriles under neutral conditions, the reaction of which is called the Ritter reaction conducted normally in strongly acidic media. Scope and limitation of this reaction were studied in terms of the susceptibility of several functionalities.

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For the purpose of enhancing the fluorescent intensity of Rhodamine 6 G (R 6 G) in aqueous solution, additional effect of various dispersing agents and polymers to the solution was studied. The largest fluorescent intensity was obtained by using both the caffein and the polyallylamine, and the characteristics of this solution system followed the Fokker-Planck equation.

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