SiO₂-TiO₂ pillared montmorillonite clay, prepared by intercalation of SiO₂-TiO₂ sol into the clay layer, was subjected to two drying treatments of supercritical drying with CO2 and air heat drying. The thermal conductivities of the pillared clays under the two drying treatments are discussed in view of their structure. The rmal conductivity of the pillared clay under air heat drying didnot show lower thermal Conductivity than that of air. However supercritical drying treatment with CO₂ gave lower thermal conductivity than that of air. Thermal c onductivities of gas in pillared clays under both treatments are lower than conductivity of air, since both pillared clays have smaller pore size than the length of mean free path. Therefore the difference of thermal conductivities of both pillared clays was sug gested to be due to the change of conductivities of pillared clay solid structure. By supercritical drying, card-house structure was created at silicate layer, which has lower contact each other and results in low thermal conductivity. By the increase of SiO₂-TiO₂ sol, the thermal conductivity became lower. This indicates that the increase of card-house structure portion enhanced to give lower contact each other.

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The catalytic decomposition of CFC-112 and CFC-113 (CFCs) in the presence of ethanol over iron (III)chloride supported on active charcoal was carried out under various reaction conditions. The carbon atoms of the CFCs ended up as CO and CO₂, the chlorine atoms as ethyl chloride and the fluorine atoms as hydrogen fluoride.
The catalytic activity of various metal halides supported on active charcoal was investigated for the decompo sition of CFC-113 at 210°C. It was found that the catalytic activity of several metal halide was superior to that of iron (III) chloride.
The catalytic d ecomposition of CFC-113 in the presence of various alcohols (or ethers) was performed over iron (III) fluoride supported on active charcoal in order to investigate the effect of molecular structure of alcohol on the destruction of CFC's. The higher homologues of n-alkyl alcohol increased the conversion of CFC-113. It is reasonable to consider that the nucleophilic reactivity of the alcohols might be increased by the inductive effect of larger alkyl groups. However, ethers with larger alkyl groups showed a smaller reactivity, because of steric hindrance of the bulky alkyl groups.
While the catalytic activity of iron (III) halides supported on active charcoal dec reased during the decomposition of CFC-113, the durability of catalytic activity was greatly improved by the addition of copper (II) chloride.

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The catalytic decomposition of various chlorofluorocarbons (CFCs) in the presence of alcohols over FeX₃/CuCl₂ supported on active charcoal was carried out in order to investigate the relationship between their molecular structure and reactivity.
It was found that ethyl chloroforma te was an intermediate in the catalytic decomposition of carbon tetrachloride in the presence of ethanol. Therefore, the catalytic decomposition of CCl₄ is initiated with the dissociation of CCl₄ into CCl₃⁺ and Cl^- in the presence of FeX₃. The nucleophilic attack of alcohol to CCl₃⁺ may give alkyl trihalomethyl ether. It is considered that this intermediate played an important role in the postulated step, The catalytic decomposition of CFC-11 took place even at a temperature below 200°C. Decrease in the conversion of CFC-11 could be prevented by keeping the reaction tempera ture at 250°C or above.
As the reaction system was under a reductive atmosphere, iron (III) halide was reduced into low-valency iron. However, the low-valency iron was oxidized with copper (II) chloride into iron (III) chloride. Thus, the copper-assisted catalytic decomposition of CFC-12 could be continued for a long time at 330°C. The more fluorine atoms CFCs had, the harder the catalytic decomposition of them became, owing to the increase in the bond dissociation energy.

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SiO₂ powder was allowed to react with Cd(OH)₂ for 1 week and 2 months respectively, after adjustment to various pH's by adding some aliquots of KOH to the 0.005 M of Cd(NO₃)₂ solution containing SiO₂ powder. Potentiometric titration curves for solutions with and without SiO₂ powder were obtained by plotting pH of each test solution after the reaction as a function of the amount of K OH added. X-Ray diffraction and scanning electron microscopy were also performed for the reaction products. Formation of Cd(OH)₂ and cadmium silicate occurred after 1 week and 2 months, respectively. Differe nce in the shape of potentiometric titration curves of the solutions with and without Si02 powder was f ound, which suggested that there was the difference between the state of Cd(OH)₂ precipitated in the bulk of solution and that deposited onto the surface of the SiO₂ powder after 1 week of reaction. The shape of the titration curve obtained after the reaction of 2 months reflects the formation of cadmium silicate. The formation of cadmium silicate was found to occur by the reaction of SiO₂ powder with Cd(OH)₂ in the pH region of near 8 where SiO₂ powder was hardly dissolved. It is concluded that cadmium silicate is formed by the reaction consisting of deposition of Cd(OH)₂ onto SiO₂ powder surface by adding KOH and subsequent interfacial reaction between the deposited Cd(OH)₂ and the substrate of SiO₂ powder, and not by the reaction of the dissolved silicic acid with cadmium ion in the solution.

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The characteristics of sepiolite for the separation of carbon dioxide from N₂-CO₂ mixture were evaluated by gas chromatography. It was found that the heat of adsorption of carbon dioxide became higher and the separation ability improved with the heat-treated temperature for sepiolite in the range between 573 K to 873 K. The heat of adsorption is about 53 kJ/mol for all the samples heat-treated at 873K. These effects were considered from the viewpoint of the removal of water molecules as follows: when the water molecules coordinated to the edge magnesium atoms both inside and outside of the channels are removed by heat-treatment, magnesium ions form electrostatic fields which polarize the sorbate thus creating an affinity for carbon dioxide.

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In order to clarify the features of complex formation and characteristics of pillared micas, chromia pillared fluorine micas were prepared from polynuclear hydroxochromium (III) solutions (PHC) having different OH/Cr ratios and expandable Lit-exchanged fluorine mica [Li_0.8Mg_2.2Li_0.8(Si₄O₁₀)F₂]. The chemical species in PHC as well as the intercalated species into the interlayer region of mica were identified by high performance liquid chromatography (HPLC). At the early stages of adding NaOH solution to chromium (III) chloride solution, Cr-oligomers such as dimer and trimer were formed with decreasing a monomeric species. However, when the OH/Cr ratio of PHC increased, polynuclear hydoroxochromium (III) with widely distributed molecular weight were formed. Ratios of the monomer, oligomers and polymers in PHC changed with heat treatment; the dimer and trimer were transformed into the tetramer and polymers having apparent fractional molecular weight of 10000-300000. When solutions containing polymers of low average molecular weight were used, oligomers (trimer, tetramer etc. ) were selectively intercalated. On the other hand, when solutions containing polymers of higher average molecular weight were used, monomer was also intercalated, resulting in the decrease of the amount of fixed Cr. The basal spacing d₀₀₁ of pillared micas (200°C) showed almost constant value despite the difference in the amount of fixed Cr. This indicates no distinct relation between basal spacing and amount of fixed Cr.

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The α -tricalcium bis (phosphate) (α -TCP) was hydrolyzed in solubilized collagen solutions of several collagen concentrations (0.05 to 0.4%) for pH 5 at 30° C for 24 hours. The resulting hydrolyzed products were investigated by X-ray diffraction, Fourier transform infrared spectroscopy, thermal analysis and chemical analysis. The main hydro lyzed products were hydroxyapatite (HAp) and octacalcium dihydrogen hexakis (phosphate) (OCP). The formation of HAp and OCP was accelerated in solutions of collagen concen trations over 0.2%. It was suggested that collagen was dispersed uniformly in hydrolyzed products and formed composite with HAp and OCP by interaction among them. HAp in the hydrolyzed product was nonstoichiometric hyd roxyapatite (DAp). As the product contained OCP and collagen in addition to DAp, it might be useful as a raw material of bio-materials.

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Synthesis of (6E, 9E)-2, 3-epoxy-3, 7, 11, 11-tetramethylcycloundeca-6, 9-diene (2) from humulene (1) by the known method has been carried out through 4 reaction steps, in very low total yield, and the final step needs troublesome purification of 2 by chromatography over silica gel impregnated with silver nitrate (10 per cent). In order to overcome the above problems and research for reactions leading for epoxide 2, we developed a new synthesis of 2 from 1 in good total yield.
Diepoxidation of 1 with 2 molar amounts of m-chloroperbenzoic acid p roduced compound 8, of which purification was done by recrystallization from hexane. Selective reduction of 6, 7-epoxy ring in 8 with Ti (II) into a double bond was successful and gave 2 contaminated with a small amount of (2E, 9E)6, 7-epoxy-3, 7, 11, 11-tetramethylcycloundeca-2, 9-diene (3) in 42.7% yield together with 1(27.3%)and unchanged 8(25%). By the formation of crystalline silver nitrate complex of 2 in a similar manner used for 1, pure epoxide 2 was obtainable without use of the troublesome chromatography over silica gel impregnated with silver nitrate.
Merits of our new synth etic method of 2 are: (i) it requires only 2 reaction steps to give a good total yield (32%) of 2, and (ii) very simple purification procedure is necessary to obtain 2, and the byproducts 1 and 3 are recyclable.

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The cellulose porous membranes modified with tannic acid were prepared for use as an affinity membrane for bovine serum albumin (BSA). First, cellulose membrane was treated with diaminohexane (AHC membrane). Then, tannic acid was bound to AHC membrane with its hydroxy group (AHCCOOH membrane) and carboxy group (AHC-OH membrane), respectively. The pH dependence of BSA adsorption on AHC-COOH membrane and AHC-OH membrane was investigated in a batch-wise mode and in a dead-end flow mode. As a result, the adsorption of BSA on AHC-COOH membrane was dependent on the soution pH in both mode, but that on AHC-OH membrane was not. This difference was elucidated by the changing pK of tannic acid immobilized on each membrane. The recovery of BSA from AHC-COOH membrane was also studied. When NaCl solution (2 mol/dm³) was used as a eluant, BSA adsorbed could be recovered. The citrate buffer (pH 2.0) was good as a solvent for elution.

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For practical use of the peptides with specific bio-functions it should be desirable to fix them onto a vinyl polymer substrate without spoiling their prominant function. For the fixation, a reagent named “ linker ”, should be required to mediate binding between the substrate and the peptide. Accordingly, the linker reagent should contain two functional groups having different reactivity. Here, β -allyl aspartate having both amino acid residue and allyl group w as selected as a useful linker reagent. The reagent was easily synthesized by esterification of aspartic acid with allyl alcohol in the presence of chlorotrimethylsilane as a coupling agent in a high yield and high purity. The resulting β -allyl aspartate was highly soluble in common organi c solvents such as methanol and dimethyl sulfoxide and then successfully reacted with vinyl polymers by the action of radical initiator to result in the chemical bond between polystyrene or poly (1-vinylethylene) and the allyl group. The results revealed that β -allyl aspartate can be potentially used not only as the simple surface modifiers, but also as a linker reagent equiped with a function of synthesizing a peptide.

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Waste water containing chromium (VI) is oxidized by ozone under ultraviolet (UV) radiation.
The waste water after the oxidation process is purified by passing through a cation exchange resin column and then through an anion exchange resin column. The period of time required for o zone to oxidize chromium (III) and organic matter with UV radiation was only one third of that without the radiation.
Electric conductivity of the effluent w ater from the anion exchange resin column was less than 20 μ S/cm. This deionized water can be reused as rinsing water in the plating processes.
Concentrated chromium (VI) solution discharged from regeneration of an anion exchange resin is refined by a proper ion exchange method. Chromium (VI) solution with high purity is recovered from this solution.
Ba sed on these experiments, we devised a practical recycling system where water in t oxic chromium (VI)waste water can be reused as deionized water on an industrial scale at a plating factory, and chromium (VI)in the waste water can be also recovered as the raw material of chromium.

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To improve the functional properties of Nylon-6, several s-triazine compounds with phenoxy and sulfonate substituents were synthesized and reacted with Nylon-6 in melt state. Especially, sodium 4(4, 6-diphenoxy-1, 3, 5-triazin-2-ylamino) benzenesulfonate (1a) consisting of a s-ulfanilic acid unit was found to react selectively with the terminal amino groups without decreasing its original solution viscosity, when the molar ratio of la relative to the terminal amino groups of Nylon-6 was 1-2. The reaction was confirmed by the decrease of the terminal amino groups. Sodium 4 ( 4, 6-diphen oxy-1, 3, 5-triazin-2-ylamino) ethanesulfonate containing taurine unit was also effective for the capping reaction, although the solution viscosity of Nylon-6 was much decreased probably due to the amide exchange reaction with taurine moiety. The reaction product of Nylon-6 and 1a was spun into filaments, which showed an decreased dyability to an acidic dye but an improved dyability to a basic dye compared with those of the original Nylon-6. When the filament was treated by the aqueous solution of poly(oxyethylene) with amino terminal groups, the water absorption was increaseed to 11%.

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Synthesis of ZSM-5 with the SiO₂/Al₂O₃ ratio of 100 and silicalite under elevated gravity was carried, out using a centrifuge oven. It was found that the crystallization rates of ZSM-5 and silicalite are enhanced under elevated gravity. It was also found the maximum crystal sizes of ZSM-5 and silicalite synthesized under 100 G are about 2 times larger than those synthesized under 1 G.

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