Mesophase pitch has been recognized a most promising precursor for the carbon fiber of excellent properties and reasonable cost. Mitsubishi Gas Chemical Company and Kyusyu University proposed an application of HFBF3 as the catalyst for the condensation of aromatic hydrocarbon directly into mesophase pitch. Structure of starting aromatic hydrocarbons and reaction conditions allow to control the structure, composition and properties of the pitch. Thus the chemistry of the mesophase pitches in terms of their preparations, structures and properties can be clarified on molecular bases. Their reasonable cost and excellent properties allow their applications in board areas of carbon industry other than carbon fiber. Very high yield achieving, rapid reaction, complete recovery and repeated use of the catalyst, no necessary of purification and a simple line of facilities reduced tremendously the price of resultant mesophase pitch even if pure chemicals are used as the starting feed.

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Preparation of superconducting films by Dipping-pyrolysis process was studied in the following items. (1) Selection of the solvents and starting metal-organic compounds. (2) Thermal decomposition mechanism of metal-organic compounds; (Y, Ba, Cu) naphthenates and laurates in the prefiring stage. (3) Reactions between superconductive films and substrates (YSZ and SrTiO3) (> 850°C) (4) Effects of oxygen partial pressure and temperature in the final heat treatment. (5) Selection of the substrates. (6)Effect of the addition of silver. (7) Epitaxial growth of films with c-axis-, a-axis- and [110]-orientations on SrTiO₃ single-crystal substrates and their morphology and crystal structure. (8) Critical current density of the c-axis-oriented epitaxial films and its dependence on the magnetic field. (9) Epitaxial growth on MgO (001) single-crystal substrates. (10E) ffect of metal buffer layers deposited on the surface of MgO and SrTiO3 single crystals. (i1)P reparation of YBa₂Cu₄O₈ and Bi₂Sr₂Ca₂Cu₃O₁₀superconductiv e films.
As a result, epitaxial growth of YBCO on SrTiO₃ single-crystal substrates was successfully controlled by dipping-pyrolysis process and critical current density over 10⁶ A/cm² was achieved at 77 K.

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Adsorption of CHC1F₂ on a series of alkali metal (Li+, Nat, K+, Rb+, Cs+) ion-exchanged ZSM-5zeolites have been studied by the analysis of adsorption isotherms and IR spectroscopy. At low temperature (273 K), physisorbed CHC1F2 molecules filled up the pore of ZSM-5 zeolites whereas the isosteric heats of adsorption were much larger than the heat of condensation of CHC1F₂ irrespective of the cation incorporated in the zeolite. It was indicated, therefore, the adsorption in these systems was governed by the dispersion force of pore wall. The microscopic character of admolecules was, however, strongly affected by the electric field of the cation. IR spectra of adsorbed CHC1F₂ indicated that the C-H bond of the admolecule was oriented in the parallel direction with the electric field exerted by cation site, and these orientation resulted in a decrease in the intensity of vc_H band and the low frequency shifts of vc_a band. At high adsorption temperature (469 K), surface analysis showed that a part of adsorbed CHC1F₂reacted with Al in the zeolite framework in a manner to form a surface compound containing F and Al atoms.

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Catalytic properties of supported transition metal catalysts were investigated for conversion of aqueous solution of ethanol in gas phase in order to use effectively ethanol solution from fermentation of biomass. Fourteen supported-metal catalysts (Ti, Zr, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, Sb, Ru, Pt and Rh)were prepared by impregnation of aqueous solutions of their salts on alumina. Reactions were carried out at atmospheric pressure and 673 K by use of a conventional flow reactor. When mixture of ethanol and water vapors was fed on the metal catalysts, ethylene, acetaldehyde and acetone were produced as in the case of the metal oxide catalysts. However, on the metal catalysts of Group 8-10, carbon dioxide, carbon monoxide and methane were produced, suggesting that the steam reforming of ethanol occurred. The selectivity for the reaction was in the order: Co>>Ni> Rh > Pt, Ru, Cu. This is practically the reverse order for methanol steam reforming. On Co/Al₂O₃ the ethanol steam reforming occurred directly without going through methane formation.

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Quantitative analysis of cyanamide in lime nitrogen fertilizers rs studied by liquid chromatog raphy. A portion of ground lime nitrogen fertilizer was dissolved in dilute hydrochloric acid. Extracted cyanamide f rom fertilizers in the solution was determined by the reversed phase ionpair liquid chromatographic tmethod reported by Skelly. Effects of pH of the solution in the range of 0.2 to 13.5, extraction time and emperature on stability of cyanamide were examined. It was found that cyanamide is stable for more than 7 hours in aqueous solution in the pH range 2.5-8.5. Cyanamide was converted to urea at pH lower than 2.5, while dimerization of cyanamide occurred in the pH range 8-12. The former and latter reac-ti ons were first order in hydrogen ion concentration and hydroxide ion concentration, respectively. Thcey caanlacmiuimde contents of the powder and granular type lime nitrogen fertilizers were deter mitnhleid qc uhbirydo mato graphic method and compared with the values by the Japanese official method us-i ng silver ion precipitation. There was a good relationship (correlation coefficient: 0.990) between the values obtained by the two methods for the powder type fertilizer. On the contrary, in the case of granu-L ar type one, there was poor relationship in the calcium cyanamide contents b the Japane se official method. It was proved that many kinds of cyanamid y the present method and e derivatives such as dicmnodiamide, melamine and some unidentified compounds existed in the granular type li. These compounds are produced at granulation process of the fe me nitrogen fertilizer recipitate on addition of silver ion in an ammonium alkaline soluti rtilizer and easily formed on. It is shown that this new method sIn uds ethfuisl mfoert hraopdi di sa nedff eqcutiavnet itfaotri veev aalnuaaltyiosnis ooff cyanamide and its derivertives of lime nitrogen fertilizers, process conditions and quality control of these fertilizers.

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(+)-a-Pinene (1), (-)-β- pinene (2) and (-)-l-verbenone (3) were converted to primary and/or secondary amines (4, 5 and 6) by hydroboration, swern oxidation, oximation (N, N-dimethylhydrazonation, methylation and elimination reaction) or reduction with LiA1H4. These amine derivetives were condensed with six kinds of chloride to obtain urea compounds 4a-4e, 5a-5e and 6a-6e and amide compounds 4f, 5f, 6f. Eighteen terpene derivatives obtained were tested for growth regulating activity toward plants and insecticidal activity toward. Tyrophagus putescentiae (T. putescentiae) and Dermatophagoides farinae (D. farinae). On filter paper, compounds 4a-4f and 6a-6f from 1 and 3 showed greater insecticidal activity of 69-100% at the concentration of 1.0 g/m² against. Toward D. farinae the activity of these compounds was higher than that of N, N- diethyl-m-toluamide (DEET). D. farinae was almost eradicated at the concentration of 0.5 g/m² for compounds 4a, 4b, 6a and 6b. t Studies on the Synthesis of PhysiologicallyA ctive Substance. Part 15.

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The effect of the guanidine hydrochloride on the retrogradation of waxy corn starch gel has been studied by using viscometer, X-ray powder diffraction, and Fourier-transform infrared spectroscopy (FTIR). During gelation and ageing of waxy corn starch gel, a viscosity of gel increased with time. The salt effect on an increasing rate of viscosity of waxy corn starch gel is not recognized up to two weeks and subsequently the increasing rate of viscosity decreases with increasing the amount of guanidine hydrochloride. The swollen granules, by their mutual interactions, form temporary network due to the hydrogen bond. Long-term increases in the modulus of starch gels were linked to a reversible crystallization and a formation of intermolecular hydrogen bond within the granules on storage. Crystal structure of retrograded waxy corn starch, as detected by X-ray powder diffraction, was a B-form. FT-IR study suggest that all five peaks due to the hydrogen bonds overlap in the range of 3000-3800 cm^-1and there is a difference in spectra between retrograde and native waxy corn starch gels. From these results, we proposed that the molecular structure of waxy corn starch with guanidine hydrochloride can be attributed to the strong N-H⋅⋅⋅Ohydrogen bond for a hard intermolecular interaction. t Studies on the Retrogradation of Starch. Part 2.

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The synthesis of novel metal phthalocyanine derivatives, metal anthraquinonecyanine, was reported in our previous paper. In this paper, we present a study of the electron transfer mechanism of the same derivatives in an organic solvent. Electrochemical measurements, involving cyclic voltammetry, chronoamperometry and chronocoulometry, were carried out for the above-mentioned compounds.
A pair of reversible peaks and three irreversible peaks were observed in the cyclic vol tammograms. The former peaks were attributed to the reduction of the anthraquinonecyanine ring in the metal anthraquinonecyanines. On the other hand, the latter ones were interpreted to result from the reduction of the central metal.
It was found that the mode of the electron transfer in the oxidation process is different from that in the reduction one and the reaction rate of the oxidation is slower than that of the reduction. Further, it was shown that the electron transfer process in the vicinity of the electrode surface is a diffusion controlled one which involves some weak adsorption and is followed by a succeeding chemical reaction.

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Agricultural PVC film containing PVC 65 %, DOP (dioctyl phthalate) 32 % as plasticizer, Ca-Zn stearates and surface active agent was treated at 150-250°C in 0-7 M NaOH solutions (1 M=1 mol dm^-3) for 0-12 h, in order to study the kinetics of the dehydrochlorination.
The degree of dehydrochlorination was increased as the temperature and reaction time were high and long. The dehydrochlorination was reached maximum in 3 M NaOH and declined over 3 M NaOH. The dehydrochlorination was increased rapidly higher than 200°C, and reached ca.100 % at 250°C over 5 h.
The dehydrochlorination progressed in first order kinetics and the apparent activation energy was 30 kcal/mol.

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The polymer electrolyte membranes (AAc/SSS membrane) were synthesized by the radiation-induced graft polymerization of acrylic acid (AAc) and sodium 4-vinylbenzenesulfonate (SSS) on a polyethylene film. The single cells using the synthesized polymer films as the electrolyte were tested continuously. In the case of AAc/SSS membrane contacted directly with the oxidizing catalyst (Pt) in oxygen electrode at 55°C, the cell voltage dropped significantly after only 5 h operation due to an oxidative degradation of the membrane. When the oxygen electrode was impregnated with an ionomer of perfluorocarbon- sulfonic acid to prevent the AAc/SSS membrane from its direct contact with Pt ele ctrocatalysts, the cell worked continuously for 212 h at 55°C and 71 h at 70°C. When a thin fluorinated polymer electrolyte membrane (F-membrane, thickness = 11μm) was sandwiched between the AAc/SSS membrane and the oxygen electrode impregnated with the ionomer, the significant degradation of the AAc/SSS membrane was delayed until 190 h at 70°C. It is considered that the AAc/SSS membrane was oxidized by active oxygen (radical) species and/or hydrogen peroxide produced at the cathode side.

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Pigment dispersion is one of the biggest important problems in coloring industries. Authors applied the micro pore distribution analysis, proposed by BARRET, and micro pore volume analysis (de Boer, t-plot analysis) to the pigment (copper phthalocyanine blue pigment) dispersion.
Pigment samples with different particle size, different drying conditions and different surf ace character were prepared for the study. Micro pore analysis using N₂ gas adsorption and desorption measurement could be good way to estimate the pigment agglomeration structure and the dispersibility of each pigment sample. Pigment dispersion and color strength reading made by ordinary pigment dispersion technique, showed good relation with micro pore analysis.
Samples having lar ge number of micro pores at smaller micro pore size on the distribution curve showed good dispersibility, and larger micro pore volume directly related to the dispersibility of the pigment.

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The reactions of methane with carbon dioxide were carried out at 1073 K over the perovskite-type catalysts, LnFeO₃ (Ln = La, Pr, Nd, Sm, Gd). The order of the reaction activities was La>Pr>Nd>Sm>Gd.
From the results of XPS measurement the decline to the ionic character of the Fe-O bond led to the decrease of the activity.
The catalyst h aving the character that is rich in acidic or basic property, especially in the former case, exhibited the low selectivity to hydrogen. The NdFeO₃ catalyst, which has the same amount of both acidity and basicity gave the highest selectivity to hydrogen.

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