Special qualities such as high clarity and low birefringence, high humidity resistance, high heat resistance and fine moldability are required for optical plastics. Cycloolefin polymers (COP) with a better balance of properties for optical materials have been developed by Nippon Zeon Co. Ltd., and commercial production was started in 1991. The COP is prepared by ring-opening metathesis polymerization of norbornene type monomers, followed by complete hydrogenation of double bonds.
The hydrogenated ring-opening metathesis polymers (HROP) derived from norbornene type monomers with bulky aliphatic substituents are amorphous and have good transparency, small photoelastic coefficients to reduce birefringence of molded articles, and high glass transition temperatures to keep heat resistance. HROP without any hygroscopic groups, especially, provide an outstanding feature in extremely low water absorption, demonstrating excelence in moisture resistance and high reliabilities for optical articles.
HROP ha ve already been produced on a commercial basis and have been employed for various high performance optical articles such as lenses, prisms, mirrors, optical discs, sheets for LCD, cells for optical analysis, etc.

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The hydrogen bonding interaction and the amino-imino tautomerization of the 2-aminopyrimidine (2APM) /acetic acid system in the solvent of isooctane (2, 2, 4-trimethylpentane) were investigated at room temperature by means of the UV and fluorescence measurements. The UV, fluorescence, IR, and Raman spectra of the 2APM/acetic acid system were compared with those of 1-methyl-2 (1H)-pyrimidinimine (MPMI) and 1-methyl-2 (1H) -pyridinimine (MPI). From the analysis of the UV spectra of the 2APM/acetic acid system, the equilibrium constant and enthalpy change for the hydrogen bond formation of 1: 1 amino-form were determined as 6.3 x 10² dm³ mol^-1(20°C) and 50.6 ± 0.8 kJ mol^-1 respectively. The similarity of the vibronic band's position of the fluorescence spectrum of th e 2APM/acetic acid system with those of MPMI suggests that the new emission band at about 458 nm is attributed to that of 2 (1H) -pyrimidinimine acetic acid complex (imino-tautomer) associated with the hydrogen-bond complex of 2APM and acetic acid in the excited singlet state. In addition, the vibronic bands of the fluorescences of the imino-tautomer and MPMI were assigned to the stretching vibrations of the C=N bond and ring C = C, N-C², and N-C6 bonds and the in-plane bending vibrations of the N-H and ring C-H bonds.

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Concentrations of heavy metals and lead isotope ratios in annual rings of the Red Pine trees were measured. The Red Pine trees were collected in four sites located in the western parts of the Honshu Island of Japan; two sites were beside the industrial areas and the other two sites were in the non-industrial areas. Concentrations of lead, cadmium and zinc in annual rings collected in the industrial areas were higher than those collected in the non-industrial areas. Concentrations of lead in annual rings increased since 1940s-1950s and lead isotope ratios also changed at the same period, suggesting that sources of lead in annual rings were changed at the period of 1940s-1950s. Lead concentration reached the highest level in 1960s-1970s, and then began to decrease steeply, regardless of sampling sites. Lead isotope ratios were not affected by the decrease of lead concentration. Although the sources of anthropogenic lead were complicated, the gasoline additives and industrial air dusts would be one of the major sources for the lead pollution since 1940s-1950s. Concentrations of cadmium and zinc in annual rings were also decreased since 1960s-1970s in the same manner as lead. Vertical profiles of lead concentrations and lead isotope ratios in coastal sediments collected in the Hiroshima Bay were compared with the chronological change in annual rings. There were some differences between chronological distribution of lead and lead isotope ratio in annual rings and those in sediments; In other metals, such as manganese, calcium, aluminum and copper, characteristic changes of the chronological distribution found for the heavy metals in annual rings could not clearly seen and concentrations were independent of the sampling sites.

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Schenck reaction, which is the oxidation reaction of alkenes having allylic hydrogen (s) with singlet oxygen (¹O₂) to give hydroperoxide (ROOH), is the one of the most useful reactions to introduce oxygen function into the allylic position.¹O₂, which is one of the active oxygen, has been clarified to be involved in the various physiological phenomena. In order to accumulate and analyze the geometrical and energetic information to predict the reactivity and regio- and stereoselectivity (to predict the major stereoisomeric product) for the reaction, the transition structures for Schenck reaction of singlet oxygen (¹O₂) with some alkenes (methyl-, vinyl and formyl substituted alkenes) have been located with ab initio molecular orbital theory. All stationary points, including transition structures were optimized with no geometry constraint at the RHF/ 3-21G basis set.
The methyl substitution makes the transition structure earlier and more stable (the increase of methyl group on alkenes makes the transition structure more stable and the activation energy decreases (≈3 kcal/mol) proportionally with the number of methyl group). The position of methyl subst ituent (s)changes the transition geometry: All cis-substituted alkenes have the transition structures including 3membered ring structure formed by 0², C1 and C² atoms (Scheme 1).
The oxidation by ¹O₂ or OH radical of allylic position can be conside red to be the plausible mechanism of the peroxidation of unsaturated fatty acids or some hormones having X-CH₂-X type allylic methylene group (X=cis substituted double bond), such as prostaglandins. The RHF/ 3-21G transition geometries and activation energies for Schenck reactions of 9a-b having vinyl group and 11a-c having formyl group show that the methyl substitution at C¹ position (see Scheme 2) lowered the activation energy, though the energy did not hardly change by the substituents at C³ position. The small activation energies for the reaction of ¹O₂ with 9 and 11 indicate that the methylene group (CH₂) between two double bonds is easily oxidized by Schenck reaction, suggesting the possibility for the involvement of active oxygen such as ¹O₂ for the peroxidation mechanism of some biomolecules.

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Pseudomonas cepacia lipase (PCL) catalyzed transesterification between tributyrylglycerol (1) and 2octanol (2) to give (R)-1-methylheptyl butyrate (3) has been studied using eight kinds of organic solvents at 10-70 °C. The enantioselectivity expressed as log E (where E is the enantiomeric ratio) was negatively correlated with the solvent hydrophobicity log P (where P is a partition coefficient of a given solvent between octanol and water) except bulky solvents, in which the log E values were smaller than those expected from log P. The log E against log P plot was varied by the reaction temperature (T). The enantioselectivity increased with T for the reaction in the bulky solvents, was independent of T in heptane, and decreased in the others. Activation parameters ( ΔΔH‡ and ΔΔS‡) were determined using a linear correlation between ΔΔG‡ (= RT ln E) and T. The ΔΔH‡ values were negative for the reactions in the bulky solvents and positive in the others, and the ΔΔS‡ values in the former were larger than those in the latter.
From the a bove findings, it was concluded that the enantioselectivity was affected by a combination of the nature and structures of the solvent and the reaction temperature. A plausible active site model of PCL was proposed and discussed.

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A low melting point copper complex was found as a copper precursor which can be vaporized in the liquid state when YBa₂Cu₃O_7-δ thin films are prepared by metalorganic chemical vapor deposition (MOCVD). It is confirmed that bis (6-ethyl-2, 2-dimethyl-3, 5-octanedionato) copper (Cu (EDMOD) ₂) is suited for a copper precursor for MOCVD from the result of melting point measurement and thermal analysis. CuO thin films could be prepared by MOCVD using liquid Cu (EDMOD) ₂ heated at the temperature higher than its melting point (78 °C).
It is expected that Cu (EDMOD) ₂ can be used in the range of 80-90 °C as a copper precursor to prepare YBa₂Cu₃O_7-δ by comparison with one of the conventional copper precursors, bis (isobutyrylpivaloylmethanato)copper (Cu (IBPM)₂).

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The reaction of silicon with methanol using a copper (I) chloride catalyst in biphenyl at 220 °C for 10h gave a mixture of trimethoxysilane and tetramethoxysilane in an 82% silicon conversion. Under these conditions, the selectivity for trimethoxysilane was around 80%. The optimum conditions for the reaction were as follows; 200-220 °C of the temperature, dropwise addition of methanol for 10 h, (0.7-1.4) x 10^-2 molar amount of the catalyst, and 6 molar amounts of methanol to metallic silicon.
Time course of this reaction was examined for 10 h. The amount of trimethoxysilane for mation reached a maximum in 2 h and then decreased monotonously. The yield of trimethoxysilane decreased rapidly after 7 h. While the cumulative silicon conversion increased linearly to ca.80% in 10 h, the selectivity for trimethoxysilane showed above 90% for 7 h and then decreased to 78% at the final. The overall selectivity for trimethoxysilane for 10 h was 90%.
Trimethoxysilane was found to suffer alcoholysis easily with a large excess of methanol to afford tetramethoxysilane at room temperature.

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For recycling, waste rinse water from electroless nickel plating is oxidized with a hydrogen peroxide (H₂O₂) -iron (II) ion system, known as Fenton's reagent, and treated followed by coagulation with reuse of Fe3+ ions oxidized by H₂O₂. The oxidized solution was desalinated with a reverse osmosis (RO)membrane. It was then passed through a cation exchange resin column and an anion exchange resin column in series. The coagulation after oxidation decreased COD, nickel ion, SiO₂, and suspended solid matter well.
Water deionized by the ion exchange method after desalting with an RO membrane can be reused in the final rinsing process. The electric conductivity of permeated water from the RO membrane did not exceed 13 mS/m and effluent from the anion exchange column was less than 1 mS/m.
Based on the present experimental results, we derived a practical wastewater recycling system for electroless nickel plating. This recycling technique has enabled the reuse of wastewater for electroless nickel as deionized water for the final rinsing process.

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We have measured the temperature variation of the ¹³Ca nd ¹¹⁹Sn-NMR spectra of bis (indenyl) tin (IV)compounds, Ph₂Sn (C₉H₇)₂ (1) Me₂Sn (C₉11₇)₂ (2) and (n-Bu)₂Sn (C₉H₇)₂ (3), in CDCl₃ solution. The free energies of activation (ΔF_c) at coalescence temperature (T_c) for interconversion between the two stereoisomers and for metallotropic rearrangement of those compounds are obtained by using the Eyring's absolute rate equation.
The ΔF_c values fo r interconversion between the stereoisomers are obtained as 64, 61 and 60 kJ/mol for 1, 2 and 3, respectively (Table 2), and the ΔF_c values for metallotropic rearrangement are 67, 65and 63 kJ/mol, respectively (Table 3). For all compounds, the ΔF_c values for metallotropic rearrangement are higher than those of interconversion between the stereoisomers.
Thuse, it is found that by elevating temperature bis (indenyl) tin (IV) compounds, 1, 2 and 3 react in two steps, namely, interconversion between the stereoisomers occurs followed by metallotropic rearrangement.

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Ni-Ga spinel type double oxide has been found to be highly active for the selective reduction of NO with an aid of hydrocarbon. The catalytic activity was enhanced with the increase of the Ga/Ni mole ratio. The maximum activity was observed at 3.0 of Ga/Ni mole ratio. The catalytic activity and its ternperature range of the Ni-Ga spinel type mixed oxide catalyst were improved with addition of Co/CeO₂by mechanical mixing. This new catalyst also exhibited high thermal stability.

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Reaction of cellulose with propylene oxide (P0) under base-catalyzed conditions produces hydroxypropylcellulose (HPC) HPC thus obtained was a high molecular weight polymer (Mn =18000-163000, Mw=37000-366000). We analyzed its structure by ¹H- and ¹³C-NMR, and assigned the C2, C3and C6 peaks in the ¹³C-NMR spectra by comparing the chemical shift differences between before and after the addition of PO, then obtained the MS (Molar Substitution) and DS (Degree of Substitution). As a result, the order of the relative reactivity of PO toward the hydroxy group was 6-OH > 2-0H > 3 -0H, which was same to the generally accepted order of the reactivity in the literature. It wa s also found that distribution of PO in HPC differed by quantity of oxidant in making an adjustment of molecular weight of HPC.

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