Radical cyclopolymerization of perfluoro (ω-vinyloxy-1-alkene)s (CF₂=CF–O–(CF₂)_x–CF=CF₂) (x = 1, 2) yields amorphous plastics which have high optical permeability and solubility besides features of commercial perfluoropolymers (i.e. outstanding thermal and chemical resistant, low dielectric constant and refractive index). The polymer from perfluoro (4-vinyloxy-1-butene) (x = 2) has a higher T_g and is useful for leading edge electronics and optical applications. The polymerization behavior can be classified to the conventional radical polymerization where 5 membered ring formation is dominant. Fluorination of the end groups gave an optical material which has the highest optical clarity at wide wavelength range (200 nm to 1500 nm) of the known organic polymers. Modification of the end groups to aminosilane moieties gives adhesive character to the polymer. Such modifications made it possible to apply this resin to optical fiber, pellicle, antireflective coating, low-K for LSI etc.

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Hinokitiol (4-isopropyltropolone)-intercalated layered double hydroxide (LDH) has been tried to synthesize by the calcinations-rehydration reaction (reconstruction method) using the M²⁺–Al³⁺–CO₃²⁻ LDHs (M²⁺ = Mg²⁺, Cu²⁺, Ni²⁺ and Zn²⁺), and the properties and antibacterial activity of the resulting LDH have been investigated. The calcined products obtained from Mg²⁺–Al³⁺ and Zn²⁺–Al³⁺ LDHs could reconstruct to form the hinokitiol-intercalated LDH, in which the amount of hinokitiol intercalated was increased with increasing the relative quantity of the hinokitiol solution in spite of lower solubility of hinokitiol. From the X-ray diffraction analysis, hinokitiol anion in the interlayer of the LDH was arranged as parallel to the hydroxide layer in the case of smaller intercalated amount, while it was incorporated overlapping in the intercalated with increasing the intercalated amount. It was also found that hinokitiol in the interlayer was released slowly from the LDH particles by the ion-exchange and its thermal decomposition temperature became about 200 °C higher compared to hinokitiol itself, which means an increase of heat-stability. From the result of the antibacterial activity tests using Eschericia coli, the minimum inhibitory concentration was found at 800 mg dm⁻³ of the total hinokitiol concentration both in the hinokitiol-intercalated Mg²⁺–Al³⁺ and Zn²⁺–Al³⁺ LDHs.

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1,3-Dipolar cycloadditions of unstabilized 1,1-disubstituted azomethine ylide—methaniminioanilino(methylthio)methylide—(1a), to some electron-deficient double bonds gave regioselective single adducts, respectively. The regioselectivities could not be explained by Frontier Molecular Orbital (FMO) method, but could be understood only through the activation energies calculated by transition state (TS) analysis. The TS surfaces to the regioisomer assumed by FMO method have similar reaction distances. Due to two bulky substituents in 1a, on the contrary, the two reaction distances at TS leading to the real reaction products are different: the one at no-substituent site is shorter, 1.9–2.1 Å, and the other is longer, 2.4–3.4 Å. The shorter TS distance may cause smaller activation energies. These phenomena seem to come from steric influence by two bulky substituents not to be coplanar to one another in 1a. Namely, steric hindrance of two substituents in the 1,3-dipolar seems to cause asymmetric TS and to derive two-step reactions of lower activation energy.

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Effect of inorganic acid and light stabilizer on whitening of melamine-cured coating film was clarified. Based on the IR spectra of the whitening section, it was found that amounts of ether bond and triazine ring decreased and that of secondary amine increased compared to the initial material. In the whitening section stabilizer contained in the polypropylene substrate was also detected by gas chromatography. The relation between the dipping time in aqueous H₂SO₄ solution to lead whitening and the composition and the preparation conditions of the films shows that whitening occurred by the penetration of water to the coating film. Whitening occurred easily on the coating film having lower cross-linking density and/or containing light stabilizer. It was thought that the light stabilizer in the coating film caused the high osmotic pressure through amine salt formation with inorganic acid. The acceleration of whitening in the film by the elevation of drying temperature was interpreted that the rate of penetration of water was enhanced through the lowering the cross-linking density of the film.

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Studies have been conducted on the sorption equilibria of seven kinds of amino acids by anion exchange resins of strong basic type (Amberlite IRA-401B) and weak basic type (Duolite A-7).
The sorption equilibria of amino acids (A⁻) and hydroxide ion on anion exchange resin of Cl type can be expressed by following equations.
_{&nikkashi_2001_691_en1;} (A⁻ + RCl ^→_← RA + Cl⁻)
  _{&nikkashi_2001_691_en2;}  (OH⁻ + RCl ^→_← ROH + Cl⁻)
The sorption equilibrium constants of amino acids, K_A, were 14.3 (Trp), 4.76 (Phe), 1.52 (Leu), 0.909 (Ala), 0.833 (Gly), 1.00 (Glu), 0.909 (Asp) for Amberlite IRA-401B resin, and 3.57 (Trp), 2.00 (Phe), 0.714 (Leu), 2.50 (Ala), 0.714 (Gly), 0.357 (Glu), 0.333 (Asp) for Duolite A-7 resin, respectively. The sorption equilibrium constants of hydroxide ion, K_OH, were 4.00 for Amberlite IRA-401B resin and 1.10 for Duolite A-7 resin, respectively. The highest K_A value was obtained for Trp, being larger than the value for Asp by a factor of about 16 for Amberlite IRA-401B and about 11 for Duolite A-7 resin.
It was found that the sorption equilibrium constants of amino acids increase with increasing hydrophobicity except sorption of Ala and Gly for Duolite A-7 resin.

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This paper investigates processes for the wet oxidation of waste water containing environmental contaminants including each nitrophenols. In particular, the electrolysis, photocatalysis and combined electrolysis and photocatalysis methods are examined. The nitro group was eliminated by each method and a nitrate ion produced. Further, as the TOC reduced, the method of decomposition by oxidation of the raw materials was identified. The decomposition products were fatty acids. The level of TOC removal by the electrolysis method is low and the decomposition of the fatty acids is slower than with the other methods.
As the removal of the TOC by photocatalysis electrolysis methods decreased with time, it is suggested that the fatty acids are gradually oxidized. In contrast with the electrolysis and the photocatalysis methods, the raw materials were promptly decomposed by the electrolysis photocatalysis method. The rate of removal of TOC was at least 90%, and the nitro group produced the nitrate ions in proportion to the rate of removal of the TOC. It is suggested that the activity species produced by the electrolysis method participate in this process.
It is therefore concluded that the reaction of the produced electron or positive hole on the catalyst by the photocatalysis method is promoted by the function of various activity species.

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High concentration of gaseous hydrogen sulfide more than 10000 ppm has been observed in the least controlled landfill site. The waste had low organic content, and ignition loss was about 9%. It is considered that the sufficient input of rain water and aerobe activity promoted the reaction of organic matter with dissolved oxygen in the rain water, yielding water-soluble fatty acids that were readily consumed by anaerobes. The fatty acids were transported to deeper anaerobic region by entrainment infiltrating rain water. Accumulation of fatty acids is related to the evolution of high concentration of hydrogen sulfide. Lactic acid and pyruvic acid were not found in regions of high concentration of hydrogen sulfide, but existed in regions of low concentration of hydrogen sulfide. Evolution of high concentration of hydrogen sulfide requires a continuous supply of sulfate ion at this site. Sulfate ion mainly comes from gypsum plaster boards. Sulfide content at ground surface, which was the upper part of the region of high concentration of hydrogen sulfide, was 0.2 mg/g (dry earth), indicating that hydrogen sulfide did not ascend from the deeper anaerobic region to the surface.

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Silica, zirconia and silica-zirconia double coating films were prepared on aluminum alloy (ADC12) using the corresponding metal alkoxides and poly (vinyl butyral) as starting materials, and the hardness and corrosion resistance of these films were examined. First, in order to prepare silica films having appropriate thickness, the composition of the precursor solution was optimized. As a result, it was found out that 0.5 mol dm⁻³ tetraethoxysilane in ethanol solution, which was prepared by mixing of tetraethoxysilane, acetic acid and water in the molar ratio of 1 : 3 : 2 including 1 wt% poly (vinyl butyral), and concentrating by heating, was the most suitable for coating. Using this precursor solution, silica, zirconia and silica-zirconia double coating films were prepared. Vickers hardness of the coated alloy was measured, finding that the hardness of silica-coated ADC12 was about three times larger than that of bare ADC12, and the hardness of the zirconia or silica-zirconia coated ADC12 was about ten times larger than that of bare one. Furthermore, the corrosion resistance test using an aqueous solution of copper sulfate indicated that silica-zirconia coating inhibited the corrosion of the ADC12 effectively.

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When the ethanol solutions of 4-methyl-NNO-azoxybenzene (1β) (α : β = 0.0 : 1.0) and 4-methyl-ONN-azoxybenzene (1α) (α : β = 3.0 : 1.0) were irradiated with UV light, respectively, α,β- and β,α-interconversion took place with the formation of 2-hydroxy-4′-methylazobenzene (2) as a rearrangement product. A lower yield of 2 and rapid α,β-isomerization from 1α to 1β were found in the UV iradiation of 1α (α : β = 3.0 : 1.0) in sulfuric acid (60%–70% in concentration). Under the same reaction conditions, the less reactivities in ortho-migration from 1β to 2 and β,α-isomerization from 1β to 1α were observed in the irradiation of 1β (α : β = 0.0 : 1.0).

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The catalytic activity of poly(3-qunuclidinyl methacrylate) (PQM) and its copolymer (PQM-StX) with styrene was investigated in the reaction of phenyl isocyanate with 1-butanol. Their catalytic activity was compared with those of poly[4-(N,N-dimethylamino)butyl methacrylate] (PDBM) and 1,4-diazabicyclo[2.2.2]octane (DABCO) and proved to be superior to that of PDBM, but inferior to that of DABCO. The catalytic activity of PQM-StX was higher than that of PQM. This would be caused by interaction of styrene component of PQM-StX with phenyl isocyanate.

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