We succeeded in introducing an enzymatic step for the production of D-pantolactone (D-PL), a chiral building block for the commercial production of a vitamin, D-pantothenic acid. The process involves stereoselective hydrolysis step with a novel fungal enzyme “lactonohydolase” as the catalyst for the resolution of DL-PL. The enzyme isolated from Fusarium oxysporum specifically hydrolyzes D-PL to D-pantoic acid (D-PA); thus DL-PL is easily separated into D-PA and L-PL.
When 700 g/L aqueous solution of DL-PL was incubated with the fungal mycelia as the catalyst, D-PL in the racemic mixture was almost completely hydrolyzed to D-PA (96%ee). The mycelia were immobilized into calcium alginate gels for the practical purpose. When the gels were incubated in 350 g/L aqueous solution of DL-PL for 21 h at 30 °C with automatic pH control (pH 7.3), 80–100% of the D-PL was hydrolyzed. The resultant D-PA in the reaction mixture had a high optical purity (93–98%ee) and the L-PL remaining was unmodified. After 180 reaction cycles (i.e., 180 days), the gels retained about 60% of their initial activity.
Based on these results, we started the commercial production of D-PL since 1999, through which it has been shown that the present process is highly satisfactory not only in economic aspect but also in environmental one (water, −49%; CO₂, −30%; BOD, −62%; compared with the former chemical resolution method).

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Iron oxides were prepared from goethite (α-FeO(OH)) as the precursor and tested for methane oxidation. Goethite was prepared by air oxidation of suspension obtained by mixing solutions of sodium hydroxide and iron (II) sulfate and then thermally decomposed to form iron oxide. Activity for methane oxidation over iron oxide was suppressed by the sulfate ion (SO₄²⁻). In order to clarify the effects of the residual sulfate ion on the catalytic activity and crystal structure of iron oxide prepared from goethite, we prepared sulfated goethite and compared with non-sulfated one. In the case of sulfated goethite, the temperature of phase transition to hematite (α-Fe₂O₃) was higher than that of non-sulfated sample by about 30 degrees. Electrons were donated from the sulfate ion to iron ions in hematite to reduce oxidizing power of irons. This led to deactivation of methane oxidation in a temperature range between 300 °C and 500 °C and evolution of partial methane oxidation. The line broadenings of XRD peaks due to stacking faults were observed on the lattice planes except for (113l) (l : 0, 1, 2) planes, which depicts directly the skeletal arrangement of irons in hematite, suggesting that the number of the disorder of skeletal arrangement of oxygen formed during the heat treatment. Above 550 °C, the activity of hematite prepared from sulfated goethite was higher than that from non-sulfated one. At a temperature above 550 °C, the sulfate groups were eliminated from the hematite, whereas the stacking faults were remained. We conclude that the high activity of hematite prepared from sulfated goethite at high temperature due to the presence of these stacking faults.

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ZnO thin films were prepared from zinc nitrate using an aqueous solution and an ethanolic solution. Thermogravimetric and differential thermal analyses were performed for the gel. Crystallinity, optical properties and surface morphology of the thin films deposited on glass substrates by dip-coating process from the aqueous and the ethanolic solutions were studied by X-ray diffraction (XRD), ultraviolet-visible spectrometry (UV-VIS) and atomic force microscopy (AFM). The films fabricated from the aqueous solution crystallized at temperatures higher than those fabricated from ethanolic solution. The film prepared from the ethanolic solution exhibited high preferred orientation along c axis in comparison with that from the aqueous solution.

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In-flight carbonization was tried by introducing spherical phenolic resin powders of average particle size, ≈25 μm, into RF induction thermal plasma. The carbon powder was composed of highly porous particles and of the gradient structure with respect to porosity and crystal structure. The layered structure in the surface region was highly graphitized surface, while the core was amorphous. The structure was attributed to the unique nature of thermal plasma processing. Electrochemical measurements as the anode of lithium rechargeable battery also showed the insertion reaction of lithium into the graphitized and amorphous regions.

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Smectite clays were examined as catalysts for the alkylation of diphenyl oxide with long-chain olefins in liquid phase. A clay treated with sulfuric acid was characterized to have a mesopore structure and found to act as an efficient catalyst especially in the alkylation of a hindered substrate. Thus the clay can be used as a substitute for AlCl₃. Saponite with a card-house structure showed the catalytic activity similar to that of a Y-type zeolite. On the other hand, a sheet type clay (Al-Mont) showed similar activity with the acid-treated one (H-Mont) when heated at around 120 °C but lost its activity when heated at higher temperature probably because of the sheet shrinking. The following relationship between the pore size of catalyst and product distribution was noted. The catalysts with a wider pore size tend to produce more polyalkylated products and ortho isomers. Isomer distribution of arylated alkanes spread wider in the p-isomer than those in the o-isomer, which can be explained in terms of steric hindrance and olefin isomerization during the reaction. Mordenite with one dimensional micropore channel structure showed a high selectivity toward straight shape molecules. From the viewpoint of products selectivity, smectite clays were situated between homogeneous and micropore-heterogeneous catalysts, and was found to be useful for alkylation of a bulky substrate.

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Effect of film forming agent on the particle coalescence in methyl methacrylate-butyl acrylate-acrylic acid copolymer emulsion films was investigated. From the results obtained, as the solubility parameter of the film forming agent was close to the solubility parameter of the polymer and as the boiling point of the film forming agent became high, the coalescence of the polymer particles was accelerated. Also as the solubility parameter of the film forming agent was close to the solubility parameter of the polymer and as the boiling point of the film forming agent became high, Ra (surface roughness) of the film surface decreased. However, the particle coalescence of the polymer emulsion films was incomplete. In addition, it was found that Ra of the film surface had a correlation with ΔMFT (difference of minimum film-forming temperature).

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On D-lactose, C-6 and C-6′ which have the primary hydroxy groups were selectively triphenylmethylated and the remaining secondary hydroxy groups were acetylated. During detriphenylmethylation, acyl migration occurred to give acetylated lactose having free hydroxy groups on C-6 and C-46′. Polycondensation of the obtained 1,2,3,2′,3′,6′-hexa-O-acetyl-D-lactose and terephthaloyl chloride gave the aromatic polyester having lactose in the main chain.

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Natural fibers of cellulose and collagen were immersed in water and ground into submicron sized peices using a grinder equipped with grindstones.
Biodegradable superfine fibers-cement composite was prepared by mixing the superfine fibers and cement was studied. The composite was degraded in soil after several months to decay collapsed into sand. The composite buried in soil was biodegraded from the outer side of the sample by action of bacteria and mold. From DTA-TG, it was suggested that Ca²⁺ migrated from the centeral part to the outer part of the sample. The biodegradation mechanism of the composite was suggested as follows; (1) The reaction of carbon dioxide evolved by metabolism of the bacteria with free Ca²⁺ in the composite afforded CaCO₃, (2) Ca²⁺ in the central part migrated to the outer part due to lowering Ca²⁺ concentration in the outside. The superfine fibers were finally biodegraded to water and carbon dioxide.

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There have been many studies on the fabrication of microcapsules by the use of various techniques. Among these techniques, liquid phase separation method is most promising for microencapsulation of trimellitic anhydride (TMA) since it provides TMA microcapsules without using an aqueous solution. TMA, used as foaming control agent in the field of printing, was microencapsulated by liquid phase separation (called solvent displacement method) in organic solvents. The solubility parameters were used in order to determine the raw materials of TMA microcapsules. Considering the solubility parameters of polymer, copoly (ethylene/methacrylic acid) was used as the capsule wall material. In our experiments, two kinds of solvents, toluene (solvent (a)) and Isopar-L (solvent (b)), were used. The following conditions were adopted: (1) The wall material was completely dissolved in solvent (a); (2) TMA powder was well dispersed in solvent (a) but was not dissolved in solvent (a); and (3) the wall material and TMA powder were not dissolved in solvent (b). By using the mixtures of lecithin and basic barium petronate (BBP) or basic calcium petronate (BCP) as charge control agents, TMA microcapsules were charged both positively and negatively. The liquid toner prepared in this study was applicable to a commercial printing machine. Furthermore, the foaming control effects satisfied the requirements for products in the printing industry.

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Measurements of sulfur dioxide (SO₂), nitrogen oxides (NO_x), ozone (O₃), and meteorological parameters like wind speeds and wind directions were carried out from February 1997 to February 1998 at 4 sites of Mt. Gokurakuji (the elevation at the summit: 693 m), Hiroshima prefecture, in order to investigate the distribution patterns and diurnal variations of air pollutants with respect to areas of the Japanese red pine forest declines. SO₂ concentrations were low (less than 10 ppb) at every observation site. Higher concentrations of NO_x (80–330 ppb) were observed during the night time and early morning at the sites (altitude 120 m, 130 m) near the city area. NO_x concentration near the summit of Mt. Gokurakuji was as high as 20 ppb at daytime and a few ppb at the nighttime and showed the different patterns of diurnal variation from those at the sites near the city area. Concentration of O₃ at the summit was lower during north wind and increased during see breeze, which suggests that photochemically produced O₃ was transported from the city area in which NO_x was emitted. Emission rates of NO_x and the number of vehicles at the surrounding cities of Mt. Gokurakuji have been increased by a factor of 2.5 and 2.0, respectively from 1980 to 1996. Annual concentrations of NO_x at the surrounding cities have been increasing slightly from 1985 and O_x concentrations have also been increasing every year. On the other hand, SO₂ concentrations have been decreasing with the decrease of emission rates of SO_x at the surrounding cities.

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In order to catch the characteristic of the flow at saline wedge, the experiment for occurrence and flowing of saline wedge using a rectangular open channel was performed. Saline wedge is generally so stable that the visual observations are easy, and interfacial layers are measured with the aid of visualization method. As a result of the experiment, it was found that a saline wedge was reproduced well, and the form of tip of saline wedge changed by relative density and the amount of discharge on the upper reaches. It was also found that the thickness of the downstream freshwater depth was dependent upon the number of Richardson. The degrees of the dilution near the separation point could be displayed at the function with F_io in the density layer.

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A simple extraction method for the determination of the endocrine disrupting nine phthalic esters, by gas chromatography/mass spectrometry (GC/MS) with electron ionization (EI) is described. These compounds were adsorbed on a disk-format solid phase from river water, rain water and atmosphere. A capital acetone and hexane were investigated as solvents for elution of the nine phthalic esters adsorbed on the solid phase. As a result, a capital acetone and hexane turned out to be very effective and a high recovery (about 100%) was obtained for nine phthalic esters in distilled water and reagent gas. This method was successfully applied to river water, rain water and atmosphere.

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In order to raise the specific power of paste-type positive electrodes for Ni–MH batteries, the relationship between the characteristics of positive electrodes and particle-diameter of the active material (nickel hydroxide) was investigated by using different particle size of active materials synthesized by the reactive recrystallization method. The specific power of paste-type positive electrodes was improved about three times higher than that of conventional ones by optimizing the diameter of the active material. The specific power of the developed paste-type positive electrodes was almost equivalent to that of sinter-type positive electrodes. The discharge capacity of the developed paste-type positive electrodes was about 20% larger than that of sinter-type positive electrodes.

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The electrolyte matrix of Molten Carbonate Fuel Cells (MCFC) is generally reinforced with a mixture of alumina fibers to provide strength within the cell. However, alumina fibers corrode and are changed into lithium aluminate by reaction with lithium carbonate in molten carbonate. Lithium aluminate have two crystal structures in molten carbonate, α-phase and γ-phase. It is known that lithium aluminate undergo mutual crystal structure transformations between α- and γ-phase in molten carbonate. Therefore, the stability of electrolyte matrix is lowered. It is reported recently that α-lithium aluminate is more stable than γ-phase in molten carbonate. We have studied on α-lithium aluminate fiber instead of alumina fiber. We synthesized it at low temperature under CO₂ atmosphere by the solid state reaction of γ-alumina fiber with lithium carbonate. Further, it was found that α-lithium aluminate fiber was synthesized with keeping fiber structure. The evaluation of stability of this fiber in molten carbonate were performed by comparing with alumina fiber. The mixture of α-lithium aluminate fiber and α-lithium aluminate powder was stable and the crystal structure of this mixture remained α-lithium aluminate. It can be expected that application of α-lithium aluminate fiber instead of alumina fiber improve the stability of the electrolyte matrix for MCFC.

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Hydrogenation reaction of CO₂ over Rh/FSM-16 and Rh/SiO₂ catalysts prepared by impregnation method was carried out. The Rh/FSM-16 catalyst showed higher CO₂ conversion and turnover frequency than Rh/SiO₂ one. The main product was CO over SiO₂ supported catalyst, but it was CH₄ over FSM-16 supported one irrespective of reaction temperature. From the results of TEM and H₂ chemisorption, the mean particle size of Rh for Rh/FSM-16 was smaller than that for Rh/SiO₂. The ratio of chemisorbed CO to chemisorbed H was smaller for Rh/FSM-16 catalyst than Rh/SiO₂ one. It was suggested that this finding reflected the difference in product selectivity of CO₂ hydrogenation between FSM-16 and SiO₂ supported Rh catalysts.

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CO₂ hydrogenation was carried out over alkali metals such as Li, Na and K promoted silica-supported Rh–Co catalysts (Rh–Co–M/SiO₂). Na additive was most effective of the three alkali metals for ethanol formation over 5 wt% Rh–Co(1 : 1)/SiO₂. The added amount of Na influenced product selectivity as well as CO₂ conversion. The highest ethanol selectivity was obtained over 5 wt% Rh–Co–Na (1 : 1 : 0.5)/SiO₂ catalyst. The mechanism of promotion effect of Na added amount was investigated by means of in situ FT-IR observation during reaction. The variation of Na added amount changed the ratio of Rh₂–(CO)₃ and bridged type adsorbed CO species to linear type one. This finding suggested that the amount of Na affected on the hydrogenation ability of Rh–Co/SiO₂ catalysts, leading to the difference in CO₂ hydrogenation activity.

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The wet oxidation treatment of catechol and ethylenediamine was carried out. The combination of electrolysis with photocatalysis method was adopted, for these compounds can complexate easily as ligand with heavy metals and it is very difficult to treat complex compounds formed. TOC measurement showed that the waste water contained catechol only was oxidized by the combination method more efficiently than by electrolysis, photocatalysis or the combination method of electrolysis with photolysis. The same result was obtained for the waste water of cathecol contained copper or cadmium, and that of ethylenediamine contained copper. It was suggested for the acceleration effect that the combination of electrolysis with photocatalysis method could produce new active oxidizer and increase the oxidation rate to promote the decomposition of the organic compounds.

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