In order to determine the molecular geometries of 2-pyridone and 1-methyl-2-pyridone in the ground and lowest excited singlet states the ab initio molecular orbital calculations at the RHF and RCIS levels using the 6-31+G (d) basis set were carried out. And also, the molecular orbital calculations at the B3LYP level using the 6-31G (d) basis set were carried out to obtain the molecular structures of these compounds in the ground state. From calculated results the following conclusions were drawn: (1) The ring frame-works of 2-pyridone and 1-methyl-2-pyridone in the ground state are planar within the precision of the present molecular orbital calculations. (2) In the lowest excited singlet state (S₁ state: abbrev. ) the ring frame-works of these compounds are nonplanar. The angle between the plane containing the bond angle of the ring C₃-N₁-C₄ and the bond N₁-H₂ is 30.4° for 2-pyridone, and the angle between the plane containing the bond angle of the ring C₃-N₁-C₄ and the bond N₁-C₂ is 22.6°for 1-methyl-2-pyridone. (3) In the S1 state the energy differences between the nonplanar and planar structures are 4.30 and 6.72 kJ mo1-1 for 2-pyridone and 1-methyl-2-pyridone, respectively. (4) The UV absorption band of the nonplanar model at the longest wavelength side shifts to the lon ger wavelength than that of the planar model, while the oscillator strength of the corresponding band of the former model is smaller than that of the latter one. (5) In the S₁ state of 2-pyridone the planar conformation is better than the nonplanar conformation for the dimer formation and the complex formation with the carboxylic acid such as acetic acid. (6) The S₁ states of these compounds are partially of n, π* character due to the non-planarity of their ring frame-works.
Therefore, the S₁ state may be mixed easily wit h the near-lying π, π * and n, π* excited states through the vibronic-coupling and spin-orbit coupling. These couplings lead to the deactivation of the S₁ state. The reason of low fluorescence quantum yields of 2-pyridone and its relevants is due to the nonplanar structure in the S₁ state.

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General methods to get propagators under the Huckel approximation are presented for the topological reference systems of the heterocyclic conjugated molecules using the perturbation technique. We reinvestigate the off-diagonal elements of the propagators for the topological reference systems and define a new quantum chemical index for predicting the strength of a bond. Where the topological ref erence systems are the hypothetical reference systems for which construction of all substructural details of the systems, except the cycles, should be taken into account. This method enables us to discuss the influences of the heteroatom on the energy stabilization and chemical reactivity of the heterocyclic conjugated systems. Some quantum chemical quantities (such as the total π electron energy, the total π electron density, the index of the bond strength, the self-atom polarizability, and the frontier electron density)of some heterocyclic. conjugated molecules and its topological reference systems are obtained using the practical calculation method.

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The adsorption and desorption rate of dodecyl sulfate (DS) ions to and from polystyrene latex (PS) particles was investigated by the stopped-flow technique with electric conductivity detection at 25 °C and pH 5.9 below the critical micell concentration. The apparatus in this work was modified in order to study adsorption kinetics of surfactant ions at the solid/liquid interface. The modification was the sample mixing chamber making dead time shorter than the chamber used previously. The particle suspensions were rapidly mixed with sodium dodecyl sulfate (SDS) in the case of measuring adsorption rate by the sample mixing chamber. On the other hand, in the desorption the particle suspensions containing SDS were quickly diluted with ion exchanged distilled water by the equipment. In adsorption process the electric conductivity decreased with time, while in desorption it increased with time. These changes were monitored by a data store scope and a personal computer. The adsorption and desorption rate constants (k_a, k_d) of DS ions to and from polystyrene latex surface were determined to be 4.29 x 10⁵ mol^-1dm³ s^-1 and 8.71 s^-1, respectively. The usefulness of the apparatus in this reserch was ascertained with comparison between the adsorption/desorption rate constants (k_a, k_d) in the literature and the experimental ones (k_a, k_d) of DS ions to and from nylon 12 particles, which were obtained by measurement with this apparatus. The validity of the experimental adsorption rate constant (k_a) was also confirmed by estimating the adsorption rate constant (k_a') from the experimental desorption rate constant (k_d)and equilibrium constant (K).

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On the isomerization of propylene oxide (PO) to propionaldehyde (PA), acetone (AC), and allyl alco hol (AA) on five oxide catalysts (SiO₂, Al₂O₃, MgO, ZnO, CdO), the mechanism and selectivity-controlling factors of the isomerization were studied by the MOPAC-PM3 semi-empirical calculation method. A reasonable mechanism was derived from requirement that the selectivity difference of the catalysts should be consistently interpreted by the calculated electronic states of P0. With regard to the selectivity-controlling factors, it was found that PA and AC selectivities correlate closely with net charges of Lewis acid site (surface metal ion) and basic site (surface oxide ion) on oxide clusters having formal charges of 1 + (Lewis acid site) and 1-(basic site), respectively. There was no correlation concerning AA selectivity. As the result, it was supported by computational chemistry that PA and AC selectivities are used as measures of surface acidity and basicity, respectively, of oxide catalysts. These results suggest that it is a simple and effective method to derive a reasonable reaction mechanism by comparative study of semi-empirical calculations with results of experiments on a series of catalysts.

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Sodium 2-acetyl-8-hydroxyquinoline-5-sulfonate (1) and sodium 2, 4-diacetyl-8-hydroxyquinoline-5-sulfonate (2) were synthesized and characterized. The acid dissociation constant of 1 and 2, and the complex formation with Ca (II) and Mg (II) ions were determined from UV measurements in aq. solution at 25 °C: the pK_a of the phenolic OH (ionic strength: 0.1) were 7.81 (1) and 7.45 (2), and pK_a of the ring-N (Hammett's acidity function scale) were -0.31 (1) and -1.40 (2). The logarithm of formation constants of the metal complexes (the ratio 1: 1) (ionic strength: 0.1) was 3.87 (1-Ca), 1.48 (1-Mg), 3.60 (2-Ca), and 1.42 (2-Mg). The absorption maximum of the Ca complexes with 1 and 2 shifted to a longer wave-length, while there was no change in that of the Mg complexes. It is suggested that there is no chelating structure in the Mg complexes with 1 and 2 which act as weak monodentate ligands toward Mg in aq. solution.

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When a mixture of 4-dimethylamino-ONN-azoxybenzene (1α) and 4-dimethylamino-NNO-azoxybenzene (1β) (α: β=2.1: 1.0) was treated with warm 70% sulfuric acid, 4-dimethylaminoazobenzene (3) and 4- (4-dimethylaminophenylazo) phenol (4) were obtained. It was also found that 1β had a probability of isomerization to 1α, but 1α did not isomerize to 1β under the reaction conditions.
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Under the same reaction conditions, 4-dimethylnitrorylazobenezene (2) gave 4 in higher yield than 3in contrast to the case of the reaction of the mixture of 1α and 1β.
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When a benzene solution of a mixture of 1α and 1β(α: β= 3.0: 1.0) was irradiated with UV light, 5-(dimethylamino) -2-phenylazophenol (6) was obtained as a rearrangment product, and the apparent fl/a ratio (1β/1α) did not changed in this reactions. It was found that the compound 6 isomeriz ed to 1α under UV irradiation in benzene.
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When a benzene solution of the mixture of 1α and 1β(α: β=3.0: 1.0) was irradiated in the presence of trichloroacetic acid, a higher yield of 6 was obtained compared with that in the absence of trichloroacetic acid.

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Polycyclic aromatic hydrocarbons were oxidized with a wild type bacterium Bacillus cereus to afford hydroxylated compounds. After incuvation the bacteria was collected by centrifuge and the oxidation was carried out by the addition of the substrate (720 μM) at 30 °C for 24 h (pH 7). The substrates such as naphthalene, methylnaphthalene, dimethylnaphthalene and biphenyl were regioselectively oxidized to give naphthols, naphthylmethanol, (methylnaphtyl) methanol and biphenylols, respectively, in 5-26% yields. The toxicity of the products saturated the yield. The addition of an anion-exchange resin improved the yield of 1-naphthol. Also, 1-naphthol was isolated automatically by using dialysis system with a membrane tube.

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Many powder handling processes, such as grinding, mixing and conveying in the manufacturing of pharmaceutical drug are often involved in troubles due to adhesion and cohesion of bulk powders caused by static electricity. In order to clarify the cause of troubles, an apparatus was developed to evaluate the change of electrostatic charges in the bulk powder and its powder characteristics during pneumatic conveying.
The data from this apparatus were gathered for various pharmaceutical bulk powder having different physicochemical property and its granulate bulk. Since the correlation between the electrostatic charge level and the bulk powder property was observed, it was found the electrostatic charge level and adhesiveness during the operationlike pneumatic conveying of bulk powder in piping and the movement of rotation type mixer can be simulated by using the apparatus developed in this study.
The study confirmed it helps to provide the basic information for the optimization of crystallization process, powder handling operation and safe operations in plant.

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Some of the world heritage were made mainly of dried clay and exposed to rain and wind. Deterioration by weathering is remarkable, and the protections are necessary immediately.
In this work, hydrolysis product sprepared from silicon alkoxide and titanium alkoxide with aqueous HCI solution were used as the coating materials for the dried clay. These hydrolyzed alkoxide solutions permeate into pore of relics to strengthen the particle-particle binding. Protection effects of these solutions were clarified.

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Since ordinarily available phenanthrene contains impurities such as phenanthrenequinone and fluoranthene, it is difficult to determine anthracene by spectrofluorimetry directly. Trace amounts of anthracene in phenanthrene can, however, be selectively determined by using the 4th-derivative synchronous fluorescence intensity without interference of these impurities. In 5 mL of cyclohexane, 25 mg of the sample is dissolved. The synchronous fluorescence spectrum of the solution is measured with wavelength interval (Δλ) of 24 nm in the range of 360-395 nm. Trace amounts of anthracene in phenanthrene can be determined from the 4th-derivative intensity at 376 nm, which is obtained by computation of the synchronous fluorescence spectrum. By this method, anthracene can be determined simply and rapidly. The determination limit is 0.5 ppm.

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With the objective to prevent moth-eating damage caused by insects, the system containing baker's yeast adsorbed by a water-absorbing polymer, Diawet US60, was prepared. The moth-eating damage caused by Attagenus unicolor japonicus was evaluated by use of a woolen cloth (2 cm², 40 mg) with or without the system in 1 L glass vessel at 25 °C for 7 days. The moth-eating damage rates with and without the system were 3.3% and 54%, respectively, and the death rate of insect reached 100% with the system due to the respiration of yeasts.

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