New solid acid-base catalysts (Si0₂-X_m-P_n-O_p), X: alkali metal, alkaline earth metal)showed high catalytic activity and selectivity in vapor phase intramolecular dehydration of monoethanolamine (MEA) to ethylenimine (EI). Both acidity and basicity of these catalysts were controlled extremely week(+4.8< Ho, H_< +9.3). On the basis of the results obtained in the pulse reaction carried out with these acid-base catalysts and TPD and IR measurements of the catalysts, the following mechanism is concluded. MEA is preferentially adsorbed from the side of the hydroxyl group, which is then dissociated on acid and base sites of the catalyst simultaneously, and the consecutive dehydration occurs to form EI. The newly developed process using these catalysts has been operated in the commercial plant since 1990.

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Electrolytic properties in mixed binary solutions of 3-propylsydone(3-PSD)tetrahydrofuran (THF) and 1, 2-dimethoxyethane (DME) containing five kinds of lithium salts (LiPF6, LiCl0₄, LiBF₄, LiCF₈S0₃ and LiBPh₄ (Ph: phenyl)) have been examined from solvent composition and molar conductivity of the solutions. The theoretical energy density of Li/MnO₂ test cell and the cycling efficiency of the lithium electrode were also investigated in these mixed binary solutions. The molar conductivity (λ ) in mixed binary electrolyte solutions gradually increased with increasing THF and DME mole fractions (X_THF and X_DME). However, the conductivity maxima were observed at 0.7-0.9 X_THF and X_DME for four kinds of electrolytes except for LiBPh₄. The increase in molar conductivity depended on the decrease in viscosity (η ° ) of mixed solvents. It is considered that the conductivity maxima observed is dependent on the ion pair formation due to the decrease of dielectric constant in the mixed solvents with increase of X_THF and X_DME. On the contrary, no conductivity maximum was observed for LiBP114 solution. It means that the ion pair formation in LiBPh₄ solution is hard because BPh₄- ion is a very stable and a big anion. The order of λ among five kinds of electrolytes was LiPF₈> LiCl0₄> LiBF₄> LiCF₈S0₃> LiBPh₄ at XTHF and X_DME=0.6. The electrolyte solutions of O.5 mol dm^-3 LiBPh₄ at X_THF=X_DME=0.7 showed maximum coulombic efficiencies of lithium cycling more than 80%. The efficiency in four kinds of electrolyte solutions became higher at X_THF or X_DME=0.5 than in the solutions showing conductivity maxima. The energy density for Li/MnO₂ test cell with the electrolyte solutions showing conductivity maxima was higher than those with the solutions for any X_THF= X_DME. On the other hand, the energy density for the cell with LiBP114 solution was fairly lower than those with other electrolytes.

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Commercial MgO substrates were annealed in the oxygen atmosphere in order to remove impurities (H₂0 and/or CO₂) in the surface layer. The effect of the oxygen annealing was evaluated from the degree of orientation and crystallinity. The emission spectra at about 400 nm disappeared perfectly in the specimens oxygen-annealed above 1200 &deg; C as examined by the measurement of cathodoluminescence. The substrates and thin films showed a minimum surface roughness when annealed in the oxygen atmosphere at 1200 &deg; C. The crystallinity was very high. Pt films deposited on substrates annealed at 1200 &Deg; C exhibited a good [100]-orientation from the measurement of half-width for X-ray rocking curves, TEM images and electron diffraction patterns.

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The hydrolyzed products of α -tricalcium bis(phosphate) (α -TCP) formed in solubilized collagen solution for several initial pH's (pH 4 to 8) at 30 ° C for 24 h were investigated by X-ray diffraction (XRD), Fourier transform infra-red spectroscopy (FT-IR), chemical analysis and so on. For in itial pH 4 the formation of calcium hydrogenphosphate dihydrate (DCPD) and for initial pH over 5 the formation of hydroxyapatite (HAp) were detected by XRD. Further, it was found from the results of FT-IR that for initial pH 4 a s mall amount of HAp and octacalcium dihydrogen hexakis (phosphate) (OCP) were formed as hydrolyzed product, and for initial pH over 5 the formation of OCP were observed in addition to HAp. The formation of HAp was at the maximum for initial pH 5, and the amount of HAp in hydrolyzed product obtained in 0.1 mol dm-3 acetic acid-ammonia buffer solution with solubilized collagen was higher than that without collagen. Ca/P molar ratios of the products calculated from the results of chemical analysis were varied from 1.3 to 1.5, which were lower than that of stoichiometric hydroxyapatite (Ca/P=1.67). The processes of the hydrolysis of α -TCP, which were suggested by the chemical equations, were explained reasonably by the results of XRD, FT-IR and chemical analysis.

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Synopsis. fac(+)-[Cr(L-isoleu)(L-leu)₂]⋅ 3H₂O and fac(-)-[Cr(D-isoleu)(L-leu)₂]⋅ 3H₂O were prepared by a method, in which [Cr (L-leu)₂(NCS) (CH₂)] (leu=leucinato) was heated with L- and D-isoleucine, respectively, in ethanol solution (75 ° C, 5 h). Also, fac(+)-[Cr (L-isoleu)(L-leu)₂]V 2H₂O and fac(-)-[Cr(D-isoleu)(L-leu)₂]⋅ 2H₂O were obtained from the filtrate independent of the standing temperatures (5-55 ° C) at 10 days. In the case of DL-isoleucine, the diastereomeric mixture of fac(-1-)-[Cr(L-isoleu)(L-leu)₂]⋅ 3H₂O and fac (-)-[Cr(D-isoleu)(L-leu)₂]⋅ 3H₂O were prepared during heating. While, fac()-[Cr(D-isoleu)(L-leu)₂]⋅ 2H₂O (standing temperature 5 or 25° C) and fac(±)-[Cr(L-isoleu) (L-leu)₂]⋅ 2H₂O (standing temperature 40 or 55 ° C) were obtained from the filtrate. By using thi s method, the optical resolution of DL-isoleucine was suggested.

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The separation of Au(M), Pt(1V) and Pd(11) from each other is invesitigated by the use of phosphorus-containing chelate resin with tetraethylenepentamine. The proposed method is applied to the separation of Au(III), Pt(N), and Pd(10 in prepared aqua regia samples. Each of Au(110, Pt(N), and Pda) is efficiently adsorbed by passing the solution c ontaining each noble metal ion (100 mg drn-s) through the resin column at SV 120h-'. The presence of 0.2 mol -dm-3 HNO3 or the five-times amount of AVM) and Cu(10 to the noble metal ions does not affect the adsorption efficiency of those ions. Au(III), Pt(N), and Pd(H)loaded on the column is selectively eluted by using the eluent solutions in the following orders; 0.25 mol drn-3 HC1-50 v/v% acetone, 1 mol dm-8 NaOH, and 4 mol drn-3 HC1-5 wt%KBr-50 v/v% acetone. The recover y ratios of Au(III), Pt(N), and Pd(H) from the prepared aqua regia sample that has been diluted to twenty -times are 89 wt%, 85 wt%, and 87 wt%, respectively, in the presence of each 103m gdm-3 of Al(Ia) and Cu(II).

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5-Phenoxymethy1-2-oxazolidinone (PM0) has been known to show dimorphism (melting points 115 °C and 123 °C). Aqueous recrystallization gave a mixture of both forms, however, stable high-melting form was obtained from organic solutions or cooling of melted (119 °C)sample. Low-melting form was isolated by sublimation over 250 °C or rapid solidification of melted (150 °C) sample. According to DSC measurement, heat of fusion was 26 kJ/mol for the low-melting form, and 31 kJimpl for the high-melting form. Heat of transformation from low- to high-melting form was 24 kJ/mol. Microscopic observation also recognized the thermal transformation between the both forms as shown by the DSC experiments.

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3-Hydroxy-1 H-phenalen-1-ones were obtained by one pot reactions of 1- or 2-methylthionaphthalene with malonic acid or methylmalonic acid in polyphosphoric acid at 70°C for 3 h. By the reaction of 1- or 2-naphthalenethiol with malonic acid, hydroxynaphthothiopyranones were obtined in stead of 3-hydroxy-1 H-phenalen-1-ones. By the reactions with methylmalonic acid, 3-hydroxy-2-methyl-1 H-phenalen-1-ones were obtained. Furthermore, the corresponding oxygen-containing compounds were obtained by the reactions of methoxynaphthalenes or naphthols with malonic acid. The reaction path was discussed from the analysis of reaction products. These results shown that the reaction provides a useful method for the synthrses of substituted 1 H-phenalen-1-ones.

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It was found that the Wittig-Horner reaction of 3-alkyl-4, 5-dihydro-2(3 H)-thiophenone gave 3-alkyl-2-(ethoxycarbonylmethylene)tetrahydrothiophene ( 4 ). The alkylation of lithi urn enolate of 4 proceeded with isomerization of the double bond of 4 to give dihydrothio p hene derivatives. Further, it was established that the dehydration of 4 by the Pummerer rearrangement of the corresponding sulfoxide resulted is the formation of 2, 3-disubstituted thiophenes in good yields.

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O xidation of azulene ( 1 ) and 1-methylazulene ( 8 ) with peracetic acid in acetic acid at 15 °C for 3 min, respectively, gave two major products: 6-(1-azuleny1)-1 (6 H)-azulenones ( 5 ) and (12) and their norcaradiene isomers ( 6 ) and (13); the tatters were proved to be important key intermediates for novel intermolecular one-carbon transfer in autoxidation of these azulenes. The structures of the products were established on the basis of their spectroscopic (UV-vis. and MS) data. Possible reaction pathways for the formation of other products derived from the above major products (5, 6, 12, and 13) are also described.

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In order to obtain information on the dyeing mechanism of polyester fibers with anthraquinone dyes, interactions between a polyester model and anthraquinone dyes have been investigated by the analysis of UV and visible absorption spectra in terms of a modified McRae's equation. Methyl benzoate was used as the polyester model. Anthraquinone, land 2-substituted anthraquinones with electron donating groups were used as the anthraquinone dyes. The orientation force of the anthraquinone dyes estimated from the equation was 0, --2 kcal/mol, which was about 0-15% of the total dye-methyl benzoate interaction. The sum of the dispersion and induction force of the anthraquinone dyes estimated from the equation was 4-14 kcal/mol, which was about 80-100% of the total dye-methyl benzoate interaction. It appears that the dispersion force makes a considerable part of contribution to the dye-methyl benzoate interaction, and orientation force and induction force makes a much smaller contribution to the interaction.

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In order to obtain information on the dyeing mechanism of polyester fibers with anthraquinone dyes, interactions between poly(ethylene terephthalate) film (PET) and anthraqu inone dyes have been investigated by the analysis of UV and visible absorption spe ctra in terms of a modified McRae's equation. As a result, a more quantitative estimation of the interac tion was obtained. Anthraquinone, 1- and 2-substituted anthraquinones with electron donating groups were used as anthraquinone dyes. The shifts of wave number of th e absorption maxima of the dyes in dyeing PET were measured. A linear relationship was obtained between the observed and calculated freque n cy shifts except for 1-amino, 2-amino and 2-methyl amino anthraquinones. The or i entation force of the anthraquinone dyes estimated from the equation was 0-0.3 kcalim o l, which was about 0-2% of the total dye-PET interaction. The sum of the dispersion and indu c tion force of the anthraquinone dyes estimated from the equation was 5-16 kcal/mol, w h ich was about 84-100% of the total dye-PET interaction. It appears that the dispersion force m a ke a considerable part of contribution to the dye-PET interaction, and orientation force and induction force make a much smaller contribution to the interaction.

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Vibrational motions of a fullerene are investigated by use of a soap bubble model, where a fullerene is replaced by a soap bubble composed of the perfectly incompressible fluid. We have obtained the following result: (1) in case of vibration with a large angular momentum 1, its frequency approximately depends on 13/2; (2) while co, depends on M -1/2 where M is the molecular weight of a fullerene.

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Lipase from Candida cylindracea was immobilized on chitosan beads by covalent binding methods, and its application to hydrolysis of beef tallow was investigated in a biphasic organic-aqueous system. The addition of isooctane, found to be the best among the organic solvents tested, to the reaction system stimulated the hydrolysis of beef tallow by immobilized lipase strongly. The proportion of isooctane and aqueous buffer in the reaction mixture was chosen at the ratio of 1: 4. Under this condition, the reaction rate was greatly enhanced compared to that in the organic-solvent-free system, and the extent of hydrolysis reached to about 90%.

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Formaldehyde was transported efficiently across hydrogensulfite ion form anion-exchange membrane via the adduct formation reaction. The transport of formaldehyde was facilitated but onlywhen the concentration of formaldehyde in the source phase solution was low. The ion-exchange capacity of the membrane was saturated by formaldehyde distributed as its adduct in a low source phase concentration because the adduct formation constant was high. The transport of formaldehyde can be further facilitated and formaldehyde was transported against the concentration gradient with the counter-transport of hydrogensulfite ion when hydrogensulfite salt was added to the receiving phase.

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