The oxidative desulfurization-fluorination reaction of organosulfur compounds using an N-halo imide and a fluoride source is demonstrated to be an effective and mild fluorination method that allows to synthesize various types of organofluorine compounds containing a difluoromethylene unit, trifluoromethyl-substituted aromatics, trifluoromethyl ethers, and N-trifluoromethylamines in high yields with high chemoselectivity. Herein briefly summarized are the synthetic procedures for such organofluorine compounds and scope and limitations of the reaction. The reaction is applied to the synthesis of novel liquid-crystalline materials having a fluorine functional group such as an N-trifluoromethylamino, trifluoromethoxy, or 1, 2-difluoroethylene group. The fluorine-containing liquid-crystalline materials are compared with the corresponding non-fluorinated materials in respect to phase transition behaviors and electro-optical properties. The novel fluorine-containing liquid crystals are shown to be suitable for not only super twisted nematic(STN) but also thin film transistor(TFT)-addressed liquid crystal displays.

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Our efforts have been devoted to the development of a compact, inexpensive, durable, and reliable CO₂ sensor by using semiconductive metal oxide, since the other types of CO₂ detection methods such as infrared or solid electrolyte methods are expensive or unreliable.Although it was well known that the conductivity of SnO₂ was not altered by the change in CO₂ concentration, we have first found that the addition of lanthanum onto SnO₂ resulted in the induction of CO₂-detecting ability.The addition of yttrium onto the La/SnO₂ element much improved the durability of the sensor.Mounting of a filter with Pt-supporting silica gel over the sensor decreased the inhibitory effects of alcohol and water in air.The interference by the temperature change was diminished by introduction of a disk with a pinhole between the sensor and the filter.The combination of these improvements with newly developed computer software for controlling the sensor enabled us to commercialize the CO₂ sensor systems in 1997.

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In the case of Ni-MH batteries, the initial activation of the hydrogen storage alloy negative electrodes was promoted by adding palladium ion-adsorbed carbon powder(Pd²⁺/C). From electrochemical impedance analysis of the negative electrodes, and TEM observation and XRD measurement of Pd²⁺/C after cathodic polarization, the mechanism of this phenomenon was presumed to be as follows:
1) Palladium ion is reduced to fine palladium particles during the first charge.
2) The fine palladium particles act as active sites for charge/discharge reactions.
3) Pulverization of the alloy particles occurs due to volume expansion by the hydrogen absorption into the alloy, and new active sites are formed on the fresh alloy surface.
4) Therefore, the promotion of the initial activation of the negative electrode is observed by addition of Pd²⁺/C.

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Solvent extraction of mercury(II), zinc(II) and cadmium(II) from hydrochloric acid solutions by dihexyl sulfoxide(DHSO, R₂SO) in benzene has been investigated under different conditions. The organic extracts were examined by infrared, Raman and NMR spectroscopies. As the results, the following equilibrium equations are proposed for the extraction of mercury(II), zinc(II) and cadmium(II) from hydrochloric acid solutions by DHSO: MCl₂(a)+2R₂SO(o)⇄MCl₂·2R₂SO(o), MCl^-₃(a)+H⁺(a)+3R₂SO(o)⇄HMCl₃·3R₂SO(o), MCl^2-₄(a)+2H⁺(a)+2R₂SO(o)⇄H₂MCl₄·2R₂SO(o), where M=Hg, Zn or Cd, in which (a) and (o) represent the aqueous and organic phases, respectively. In addition, when mercury loading increases, it is seen that the equilibrium consists of HgCl₂(a)+R₂SO(o)⇄HgCl₂·R₂SO(o).

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When 2-biphenylyl benzoate(1) was treated with anhydrous aluminum chloride(AlCl₃) in boiling o-dichlorobenzene, 2-hydroxy-3-biphenylyl phenyl ketone(3), 2-hydroxy-5-biphenylyl phenyl ketone(4), and 2'-hydroxy-4-biphenylyl phenyl ketone(5) were obtained as the rearrangement products, with a small amount of 2-biphenylol. Rearrangement products 2-hydroxy-3-biphenylyl methyl ketone(6), 2-hydroxy-5-biphenylyl methyl ketone(7), and 2'-hydroxy-4-biphenylyl methyl ketone(8) were obtained in the reaction of 2-biphenylyl acetate(2) with AlCl₃ under the same reaction conditions. The yield of para-rearranged product 4 decreased with increases of the reaction time because of taking place reverse Fries rearrangement, isomerization and deacylation of 4. The yield of 7 also decreased because of reverse Fries rearrangement to 2.
The yield of para-rearrangement product 4 decreased with increasing amounts of AlCl₃. Although the Fries rearrangement of biphenylyl esters 1 and 2 may proceed via both an inter- and intramolecular pathways, the benzoate 1 showed a higher probability of intermolecularity in compared to the acetate 2.

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It is well known that poly(1, 1-difluoroethylene)(hereafter named poly(vinylidene fluoride)(PVdF)) dissolved in some ketones or lactones at high temperature forms a thermoreversible gel in the vicinity of room temperature. In this study, the interaction parameter(x₁₂) between PVdF and solvent was estimated as a function of temperature by an inverse gas chromatography(IGC) method. The correlation between gelation of PVdF solution and the magnitude of x₁₂ value was discussed. The solvents used were hexane, cyclohexanone, γ-butyrolactone, and N, N-dimethylformamide. Moreover, sol-gel transition curve was determined for four samples with different molecular weights.
The interaction parameter x₁₂ obtained for each PVdF/solvent system increased slowly with decreasing temperature. The gelation of PVdF occurred with decreasing temperature for the following two systems: one was the system where the parameter x₁₂ increased passing through 0.5 such as the system PVdF/cyclohexanone; the other was the system where x₁₂ approached 0.5 such as the system PVdF/γ-butyrolactone. The sol-gel transition curve shifted to lower concentration with increasing molecular weight.

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To use brewer’s refuse as adsorbent adsorption of metal ions and dyes on it and its chemically modified products were examined. The refuse samples used in the present study are protein rich fraction(Pr) and cellulosics rich fraction(Hr) obtained by sifting brewer’s refuse. Adsorption experiments were conducted by a batchwise method.
The ability of Hr to adsorb acid dye increased by chemical modification, especially did remarkably by diethylaminoethylation. The degree of increase greatly exceeded that by crosslinking reported in previous paper. The adsorption ability of Pr for metal ions and acid dyes decreased sharply when it was treated with alkali. However, the adsorption ability of Pr for metal ions and a basic dye could be greatly raised by treating with hydrochloric acid.

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Mixtures of poly(vinyl chloride)(PVC) and low density polyethylene(LDPE) were reacted in a flow reactor with a fixed catalyst bed at 450, 500 and 550°C with 100mL/min of N₂ as a carrier gas to clear the influence of mixing plastics on the yields of products. H-ZSM5 was used as the catalyst. Samples were injected to the top of the catalyst bed by a screwfeeder. Oil and gaseous products were recovered in the trap cooled with liquid nitrogen and in a “Tedlar^®” bag respectively. The products were analyzed by using GC. Pure PVC and LDPE were also reacted under the same conditions as the mixtures for comparing.
The mixture of PVC and LDPE in the ratio of 1:1(weight) gave almost no effect on the yield of the lighter products such as gaseous product and BTX naphthalene at any reaction temperatures, i.e. the measured products yields were almost same value as the estimation by the results from pure PVC and LDPE. However, the mixture of PVC 1:LDPE 9 gave higher yield than those estimated on the lower boiling point products in the reaction at 500 and 550°C. It is suggested that there may be an appropriate mixing ratios to give the maximum yield of such products in the reaction of mixture of plastics.
Under these reaction conditions, HCl evolved from PVC gave almost no influence on the products yields.

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The title reactions were achieved in the presence of a fluoride anion: the reaction of perfluoro-(5, 6-dihydro-2H-1, 4-oxazine)(1)with an equal amount of trimethyl(pentafluorophenyl)silane(3)provided not only a monosubstituted compound but also di and trisubstituted compounds, while the reaction of 1 with three molar excess of 3 only gave trisubstituted compounds. A significant heterocyclic ring effect was observed: the reaction of perfluoro-(3, 4-dihydro-2H-pyrrole)(2)with 3 mainly gave a dimer of 2 with a trace amount of a monosubstituted compound.

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Ball-milling of elemental powder mixtures without external heat application has been utilized as a process for the mechanochemical synthesis of high melting compounds. The mixtures of chromium, molybdenum and amorphous boron elemental powders with atomic ratios Cr:Mo:B=(1-x):x:2(x=0-1.0) were comminuted for 10-40h in a planetary ball-mill, and a single hexagonal phase(Cr_1-xMo_xB₂) was formed after 40h of milling using tungsten carbide balls. By annealing at 900-1400°C, a single hexagonal phase was still observed at the compositions of x=0-0.6. At x=0.8 and 1.0, the hexagonal phase was observed to be partly transformed to rhombohedral phase by annealing at the temperatures above 1300 and 1000°C, respectively. The variation in the lattice parameters of the hexagonal phase with x was estimated to differ from Vegard’s law because of a tendency toward superlattice formation. The rhombohedral phase was estimated to be Mo₂B_5-x type by the determination of lattice parameters.

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