The role of second-order perturbations in interchain interactions of one-dimensional electronic systems as well as in interlayer interactions of two-dimensional systems is discussed. The general features of such interchain interactions are deduced from a simpletwo-chain model. It is well known that charge density wave occurring in one-dimensional systems causes preferred structural changes such as dimerization of the nearest neighbor units. From a perturbation-theoretic analysis, the second-order term originating from two different bands in the vicinity of the Fermi level is shown to lead to an important out-of-phase coupling of charge density waves on neighboring chains. The preferred distortion is predicted for various electron counts using a “transition-density” or “transition-force” analysis. The well-known ABAB stacking of layers in natural graphite is rationalized by a transition density analysis to be a consequence of orbital interactions between graphite layers.

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In the case of Ni-MH batteries using fine nickel particles-added hydrogen storage alloy negative electrodes, the initial activation of the negative electrodes was promoted. From electrochemical impedance analysis of the negative electrodes and specific surface area and oxygen content measurement of the added fine nickel particles, the mechanism of this phenomenon was presumed to be as follows:
1) Minute rough parts on the surface of the nickel particle act as active sites for charge/discharge reactions. Rapid hydrogen transfer takes place between the active sites and the hydrogen storage alloy.
2) Pulverization of the alloy occurs due to the hydrogen absorption into the alloy, and new active sites are formed on the alloy surface.
3) Therefore, the initial activation of the negative electrode is promoted by addition of the fine nickel particles.

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On the basis of phase diagram of water solubilization or micelles in poly(oxyethylene)(6) nonylphenyl ether(NP-6)/cyclohexane solutions, the synthesis of GeO₂ particles by the hydrolysis of germanium tetraethoxide(GTE) have been carried out as a function of R_W(=[H₂O]/[NP-6]), [NP-6] and [GTE]. No any particles were formed in monomer region. However, in both the reversed and swollen micelle regions relatively uniform spindle-like particles were produced, but they were turned to cubic-like polyhedral particles in W/O microemulsion region. These particle size depended markedly on R_W(=[H₂O]/[NP-6]), whereas they increased with increasing the concentration of NP-6 and inversely decreased with increasing GTE concentration. Particle size was decreased with increasing the apparent formation rate of particles and this formation rate depended on the states of solubilized water. On the other hand, X-ray and electron diffraction measurements indicated that any particles were hexagonal and α-quartz typed GeO₂, but spindle- and cubic-like particles were polycrystalline and single crystalline, respectively. X-Ray diffraction measurement also indicated that such change of crystalline morphology was brought about by growth of(100) face of the side face of spindle-like particles.

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Selective reduction of NO with methane in the presence of oxygen using metal oxide-supported palladium catalysts was explored. Effect of various metal oxides and the conditions for catalysts preparation on the catalytic activity was investigated. Alumina-supported palladium exhibited especially highest catalytic activity for the selective reduction of NO among the other alumina-supported metal catalysts; alumina was found to be most effective as the support among several metal oxides. Although most of preparation conditions did not affect the activity of Pd/Al₂O₃, reduction at high temperature resulted in the decrease of deNO_x activity. Result for catalyst characterization indicated that alumina support had strong solid-acidity and that the Pd dispersion for Pd/Al₂O₃ having high deNO_x activity was high. The reduction at high temperature led to low dispersion of palladium supported on the same alumina. These results indicate that the solid acidity of the support and the dispersion of palladium are essential for the high catalytic activity. Concerning the reaction pathway, it was presumed that methane was first oxidized on palladium particles to partially oxidized compounds, which then reacted with NO_x on alumina support to give N₂, CO_x and H₂O.

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In order to prepare a high efficient chemiluminescent imidazole system, we tried to introduce a 2-imidazolyl group into the second position of 5, 6, 11, 12-tetraphenylnaphthacene(rubrene) which may help it to gain a very efficient chemiluminescent compound because of efficient fluorescence and low emission energy in an energy acceptor-emitter of the rubrene moiety. Synthesis of 5, 6, 11, 12-tetraphenyl naphthacene-2-carbaldehyde was planned first for preparation of imidazole ring, but it was too labile to deal with. Therefore, we decided to prepare the imidazole ring using stable 5, 12-dihydro-5, 12-dioxo-6, 11-diphenyl-2-naphthacenecarbaldehyde (8) prior to preparation of air-sensitive naphthacene part. We prepared 6-methyl-4a, 5, 8, 8a-tetrahydro-1, 4-naphthoquinone(1) followed by aromatization with 2, 3-dichloro-5, 6-dicyano-p-benzoquinone(DDQ) to give 6-methyl-1, 4-naphthoquinone(2). Diels-Alder(DA) reaction of 2 with 1, 3-diphenylisobenzofuran gave 6, 11-epoxy-5a, 6, 11, 11a-tetrahydro-2-methyl-6, 11-diphenyl-5, 12-naphthacenedione(3). Dehydration of 3 was carried out with BBr₃ to give 2-methyl-6, 11-diphenyl-5, 12-naphthacenequinone(4). 2-Dibromomethyl-6, 11-diphenyl-5, 12-naphthacenequinone(6) was prepared by bromination of 4 with N-bromosuccinimide (NBS) in the presence of benzoyl peroxide. 5, 12-Dihydro-5, 12-dioxo-6, 11-diphenyl-2-naphthacenecarbaldehyde(8) as a key intermediate for formation of the imidazole ring was prepared by hydrolysis of 6. 6, 11-Diphenyl-2-(4, 5-diphenyl-2-imidazolyl)-5, 12- naphthacenequinone(9) was prepared by reaction of 8 with benzil and AcONH₄. Strongly fluorescent 2-(4, 5-diphenyl-2-imidazolyl)-5, 6, 11, 12-tetraphenylnaphthacene(11) was prepared by reaction of imidazolyl derivative 9 with phenyllithium, followed by treatment with Fe/CH₃COOH.

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Currently, several types of 2D-NMR spectra are routinely measured. Such 2D-NMR spectral data should be applied to a structure elucidation system. The system that we have developed, SimCOSY(Simulation of COSY spectra), is for prediction of not only ¹H-NMR but also H-H COSY spectra from an input structure. It consists of a knowledge base, a substructure generation module, a prediction module, and an output module. The knowledge base consists of the correlations between chemical shifts and substructures. For the prediction SimCOSY creates HYPER codes of the substructures as a notation for every hydrogen-attached atom for an input structure by means of the substructure generation module, HYPERGEN. Environment of each focused atom in the substructure is described up to the sixth sphere. Chemical shifts of the ¹H-NMR spectrum of the substructures are predicted by referring to the knowledge base. Then, the system creates cross peak information from the input structure and the predicted shifts. Finally, the system offers results which are the predicted ¹H-NMR chemical shifts in addition to the H-H COSY information. An H-H COSY spectral pattern is depicted using the predicted information by clicking the ’draw’ button. The input structure is drawn by using ISIS/Draw, ChemDraw, or other similar applications. The linking of any drawing application which draws organic chemical structures is possible. The SimCOSY system is written in ANSI-C, FORTRAN, and Visual C and runs on PCs with Windows 95/98/NT.

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Two types of high performance porous titanium trichloride catalysts were prepared. One catalyst(Catalyst A) was converted from the solid obtained by the reduction of titanium tetrachloride with alkylaluminum followed by the treatment with dibuthyl ether and hexachloroethane. The other catalyst(Catalyst B) was prepared from the solid reduced from titanium tetrachloride with alkylaluminum by treating with ether and titanium tetrachloride successively. The kinetics of propene polymerization with these two catalysts were studied and these catalysts compared with ball-milled titanium trichloride catalyst (AA-type titanium trichloride catalyst). Though the properties of polymerization sites on these three types of catalysts are almost the same, the polymerization sites on high performance catalysts were about ten times that on AA-type titanium trichloride catalyst. As a result, porous titanium trichloride catalysts showed higher activities than AA-type titanium trichloride catalyst. Catalyst B suffered from a more significant decrease in activity than Catalyst A. This seems to be due to TiCl₄ which remains in catalyst B and causes deactivation of polymerization sites.

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The concentration of agar and KCl in agar bridge may be respectively divided into three groups according to textbooks on chemical experiment. Preliminary experiment was done to examine the difference in the property of the agar bridge by the composition of the agar bridge as follows. Each of the solutions of CuSO₄ and ZnSO₄ in water was poured into the opposite side of agar bridge, which was prepared with various compositions in a test tube. Then the diffusion velocity of CuSO₄ in agar bridge was measured. The obtained velocity in the lapse to time difference have showed a change with the composition of agar bridge. If KCl would have changed the structure of agar gel as well as sugar, the change of velocity by KCl concentration could be consistently explaned. But the one by agar concentration could not be explaned. As the effect of KCl upon the structure of agar gel has been in the stage of hypothesis, various experiments should been systematically done to explane the mechanism of the differencein the diffusion velocity of CuSO₄.

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Several silica gels containing rare earth ions such as neodymium, samarium, or yttrium, which differed in composition, were obtained readily from sodium metasilicate and chlorides of rare earth. The reaction was carried out at room temperature in an aqueous solution, pH value of which was adjusted to be below 1 at first step to generate monomeric silicic acid, and then the solution was neutralized to be pH=7. The spectral data of IR and UV of resulting gels suggested that rare earths dispersed well in silica phase. The TG-DTA analyses of gels showed characteristic exothermic peaks, which related with the formation of crystals of rare earth silicates. The types of crystals, obtained after calcination of gels at the temperature of exothermic peaks, were influenced apparently by the composition of rare earth and silicon.

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With the aid of stationary and time-resolved fluorescence spectroscopy, we investigated solvent, viscosity and temperature effects on the rate of the intramolecular fluorescence quenching process in 1-naphthylalanylglycine derivative having 1-naphthyl(electron acceptor) and diethylamino(electron donor) groups. By comparing with kinetic and thermodynamic parameters for the fluorescence quenching process of the corresponding 1-naphthylalanine derivative, it was shown that in addition to the hydrogen-bonding solvation in the locally excited singlet state of this derivative and the stability of the exciplex intermediate, the average distance between the electron acceptor and donor groups is also a factor in controlling the charge-transfer rate.

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