Electronic structures of multilayered phthalocyanine (H₂pc) complexes, including phthalocyaninato lanthanide double-decker complexes (dimers), triple-decker complexes (trimers), their radicals, and a tetramer biradical, were investigated through spectroscopic measurements, synthesis of new complexes and theoretical calculations. (1) Excited states of double-decker phthalocyaninato complexes were described using exciton-type and charge-resonance-type excitations. Assignments were given for split Q bands and B bands of lanthanide and tin phthalocyaninate dimers. (2) A new soluble crown-ether substituted trimer was synthesized to obtain detailed spectroscopic data. Previously unknown absorption bands were found in near IR region. The changes in the electronic spectra from a monomeric phthalocyaninato complex through the trimeric complex were accounted for. (3) In order to describe electronic structure of molecular assembly systems in a manner where roles of component units are explicitly represented, localized orbitals (LOs) defined to have a maximum population on a unit were used. The LOs were employed for CI calculations, thereby contributions of intra- and inter-ligand excitation s in excited states of the dimer and trimer were elucidated. Orbital energy changes on respective macrocycies of the dimer and trimer were evaluated using the LOs. (4) A hole in a radical species of the dimer was concluded to be delocalized over the macrocycles by a comparison of electronic spectra of a newly synthesized hetero-dimer, [Lu (nc) (pc) ] (H₂nc: naphthalocyanine), and two homo-dimers. Based on the hole delocalization, a description of ground and excited states of the dimer radicals was given. (5) A trimer radical generated by chemical oxidation showed an intense band at 5000 cm^-1. Energy ratio of the band to the counterpart of the dimer (ca.1/√2 ) as well as the difference of the behavior of the hole was explained. The model also correctly predicted the presence of a single intense band in Q-band region. (6) From a newly synthesized crown-ether substituted dimer radical, a supramolecular structure consisting of two dimer radicals was generated. It was shown from electronic and ESR spectra that the supramolecular structure was in biradical state where the two holes are localized on respective dimer sites.

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Hydrodenitrogenation of quinoline catalyzed by a sulfided Ni-Mo/Al₂O₃ catalyst was investigated under hydrogen pressure of 12 MPa (cold charge) in the temperature range of 300 to 375°C. Reaction products were classified into five groups; (i) tetrahydroquinolines, decahydroquinolines and their isomers, (ii)nitrogen-containing ring-opening products (propylanilines, aminopropylcyclohexanes and their isomers), (iii)denitrogenated products (propylcyclohexane, propylcyclohexene, propylbenzene and their isomers), (iv)addition products (hydrocarbons of MW = 244, 250 and others and nitrogen-containing compounds of MW = 253, 257, 263 and others) and (v) cracked products (cyclohexane, methylcyclohexane and ethylcyclohexane).
The nitrogen-containing addi tion compounds are considered to be formed by addition of denitrogenated intermediate to carbon atom of nitrogen-containing species and to produce addition compounds without nitrogen atom by hydrodenitrogenation. The reaction network is proposed.

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The association states of Acridine Orange (AO) in four kinds of ethanol solutions were studied by absorption spectra. The association state of AO would change with different concentration. A peak assigned to the AO monomer was appeared when the concentration is 4×10^-5 mol dm^-3. The AO dimer was also characterized by their difference spectra. The interaction between AO monomer and ethanol molecule was examined by the use of a simplified McRae's equation on the maximum absorption peak positions. The analyses showed that the orientation force between AO and ethanol is 57.6 cal mol^-1, the sum of the dispersion and induction forces is 219 cal mol^-1, and the hydrogen bonding force is 125 cal mol^-1.

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Tetrahydrothiophene (THT) is one of the most commonly used gas odorant in Japan. To control quality of distribution gas, a simple method is required for determination of THT. In our previous work, a gas detector tube able to determine THT in natural gas was developed. This gas detector tube is composed of indicating layer tube and prelayer tube. The principle of coloration is based on the oxidation of THT by KMnO₄. In this study, the authors investigated the reactions on indicating layer. The results were as follows: (1) The length of coloration increases with increasing the moisture content on indicating layer. (2) The reaction of THT and KMnO₄ can be expressed by following formula:
4KMnO₄+3C₄H₈S+2H₂0→4MnO₂+4KOH+3C₄H₈SO₂.

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Poly[imino (chloro-1, 4-phenylene)imino (chloroterephthaloyl) ] (ClP-ClT) was prepared by a lowtemperature solution polycondensation of 2-chloro-1, 4-phenylenediamine with 2-chloroterephtha loyl dichloride in the presence of lithium carbonate as the acid acceptor in 1-methy l-2-pyrrolidinone (NMP). The value of inherent viscosity of ClP-ClT was 2.44 dL/g in sulfuri cacid (0.5% cnc., 25°C). In order to enhance tensile properties of ClP-ClT films casted from a solution of around 200 mg of ClP-ClT in 13.3 mL of NMP and 6.7 mL of hexamethylphosphoric triamide, the films were drawn an d heat-treated under various conditions. It was difficult to enhance the mechanical properties of the films by cold and heat drawing at dry state. Therefore, the films were drawn in an NMP/Water mixture ( 80: 20, v/v) at 50°C. The drawn films were heat-treated by a two-step method. In the first step the temperature was raised from room temp to 300°C at a heating rate of 25°C/min under a tension of 80 M Pa and then quenched to room temperature. In the second step the sample was heated from the room temp to 450°C at a heating rate of 25°C/min under a tension of 15 MPa and then quenched to room tempera ture.
The values of the tensile modulus, the tensile strength at break and the breaking energy of the drawn and heat-treated ClP-ClT films (sample [5] in Table 1) were 71.3, 1.18 GPa and 10.9 MJ M^-3 respectively. These values are about 12.8, 10.6 and 2.15 times as large as those of the undrawn films ( sample [1] in Table 1).
Using the CH Nelemental analysis the heat-treated ClP-ClT films were converted at least 80% into polybenzoxazole films, thereby changing the value of the carbon.
The values of the tensile modulus, the tensile strength at break and the breaking energy of the sample [5] were changed into 73.0, 1.06 GPa and 9.22 MJ m^-3 after 2 h of heat aging at 350°C in air. These results showed the high-temperature durability of the drawn and heat-treated materials.

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The photochemical decompositon behaviors of hexacyanoferrate (III) ion ( [Fe (CN)₆]^3-) in alkaline solutions were studied in nitrogen and ozone atmosphere by means of VIS-UV spectroscopy, ion chromatography and chemical analysis. The photodecomposition of [Fe (CN) ₆]^3- was accelerated by the addition of activated carbon in nitrogen atmosphere. The effect of activated carbon was found to be due to its reduction power, because the reaction rate constants (k₁, k₁') of [Fe (CN)₆]^3- to [Fe (CN) ₅OH₂]^3-were increased five times in the presence of activated carbon. The decomposition rate constant (k₂) of [Fe (CN)₅OH₂]^3- was, on the other hand, the same as that in the absence of activated carbon. This means that the conversion of [Fe (CN)₆]^3- to [Fe (CN)₅OH₂]^3- via [Fe (CN) ₆]^4-is promoted by activated carbon under irradiation. In dark, however, [Fe (CN)₆]^3- did not form [Fe (CN)₅OH₂]^3- species. Effects of several adsorbents on the decomposition of [Fe (CN) ₆]^3- were also examined.

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The pKa of amines, mainly aniline and pyridine derivatives, were measured by indicator method in acetonitrile. In acetonitrile, the pKa of those amines have never been measured except for several amines by Kolthoff et al. As an indicator (HI), two types of indicator (different charge on HI; 1+ and 0) were used. It was found that the pKa of amines in the range of 9.55-16.1 could be easily measured by the indicator method. However, we failed to find the appropriate indicator for the measurement of pKa of amines belonging to pKa>16.1 and pKa<9.55. The values of pK obtained were almost the sam e independent of indicator used. Furthermore, the linear plot of pKa (in acetonitrile) against pKa (in water) was observed (the linear plot contains the values of Kolthoff et al.) The values of pKa of amines obtained here would be expected to be used for another studies requiring numerical analysis in acetonitrile solution.

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Reduction of permanganate ion (MnO₄-) by hydrogen cyanide (HCN) in aqueous solution was remarkably enhanced under the freezing process, in which permanganate ion was reduced to manganese dioxide (MnO₂). As compared with the several freezing speed, the rate of the redox reaction was enhanced with increasing the freezing speed. The redox reaction was found to be strongly dependent on the solution pH and the concentration of cyanide ion added.

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The aggregate states of Acridine Orange bimolecular probe in aqueous solution and micelle media were strudied by absorption spectroscopy. The absorption spectra of the solutions involving Acridine Orange (AO) change with their concentrations. On the basis of Kasha's theory on the difference spectrum between the solution of the AO monomer and that of dimer, the averaged distance between molecular planes of AO's and the dihedral angle in dimer molecules were estimated as 4.4 Å and 80°, respectively.
It was also shown that the AO dimer dissociates by the addition of surfactant to AO aqueous solution. Dissociation equilibrium of bimolecular associates (dimer) of AO was studied thermodynamically. At the temperature of 30-60°C, absorption spectra of aqueous solutions of AO showed only monomer and dimer bands. Spectral changes with varying temperature suggested that a simple equilibrium between AO dimer and monomer. The values of dissociation constant K and dissociation enthalpy δH were estimated to be 4.24-6.45×10^-5 mol dm^-3 in the range from 40 to 60°C, and 4.16 kcal mol^-1, respectively.

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Correlation and basis set effect for the Schenck reaction of singlet oxygen (¹O₂) with propene have been studied with ab initio molecular orbital theory. All stationary points, including reactants, products, intermediates, and transition structures were optimized with no geometry constraint both at the restricted (RHF) and unrestricted (UHF) Hartree-Fock methods. The energies of all stationary points were evaluated at MPn (n=2-4) levels and the 6-31G* basis set. Calculation shows that the concerted transition structure (TSc) is favorable rather than that (TSs) for stepwise mechanism. The reaction can be distinguished by the remarkably large correlation and basis set effect, and therefore, careful treatment of energy estimation should be required. The biradical character of transition structure could be evaluated by considering the fluctuation of MPn energies.

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Selective acid hydrolysis of ftdly acetylatedβ-cyclodextrin 1 resulted in restricted fission of only one of the glycosidic bonds to give maltoheptaose henicosylacetate 2 having only two hydroxy groups at bothends.The structure of the product oligosaccharide was determined by IR and ¹H - NMR spectra as well as elemental analysis. The deacetylation experiment of 2 gave maltoheptaose 3, supPorting further the structure 2. The benzoylation of 2 took place by the reaction of 2 withe xcessamount of benzoyl chloride.

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