We propose possible fromation mechanisms of C₆₀Br₆ which have been obtained by pursuing the most probable reaction sites of C₆₀ and intermediates. Each intermediate is o btained by a ddition of s ingle bromine cation or single bromide anion onto the favorable atomic site for a preceeding intermediate. Here we assume that the reactivities of C₆₀ and intermediates are determined by the nature of t heir conjugated electron systems. Reactivity indices (the total electron density and the frontier electron density) of C₆₀ and intermediates are calculated by the simple Hiickel molecular orbital method. According to our mechanisms, C₆₀Br₆ is prepared through an intermediate which has a cyclopentadienyl anion-like conjugated electron system or a more low symmetrical one. The present findings strongly suggest that the for mation reaction of C₆₀Br₆ dose not take place through a usually suggested intermediate which has cyclopentadienyl cation-like conjugated electron system. This result suggests that the bromination reaction of C₆₀ proceeds in such a manner that tha reaction intermediates become as aromatic as possible. We also propose a new hypothesis that the bromination reaction of C₆₀ proceeds in s uch a man ner that each neutral intermediate is a ttacked by bromide anion. It naturally explains why the bromination reaction of C₆₀ culminats in Car6. This hypothesis is consistent with the fact that C₆₀ has a relatively high electronegativity, and is worthwhile for being confirmed experimentally.

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Adsorption behavior of SO₂ on alkali metal (Li⁺, Na⁺, K⁺, Cs⁺) ion-exchanged ZSM-5 zeolites has been studied as a function of temperature (273 594 K) and pressure (0.7 66.5 kPa). The adsorption states have been characterized by IR, XPS, and XRF techniques. The theoretical calculation of the adsorption interactions was performed based on a simple isolated cation model. The isosteric heat of adsorption evaluated by Clausius-Clapeyron eq uation on alkali metal ion-exchanged ZSM-5 extended up to 76 kJ/mol, and it was larger than that on silicalite (ca.30 kJ/mol), indicating the strong interaction between the alkali metal cations and SO₂. The theoretical calculation has revealed that there might be two types of SO₂ adsorbates as physisorbed species on a cation. Each was mainly stabilized by the dipole interaction, or the quadrupole interaction. The observed IR spectra for adsorbed SO₂ could indeed deconvoluted into two components, showing the existence of two kinds of ad sorbed SO₂. Some irreversible adsorption of SO₂ was observed within the adsorption conditions adapted in this study. Comparison of results between the volumetric and the spectroscopic measurement of irreversible adsorption (ca.20 and 0.2 mlNTP/g, respectively) suggested that a small amount of strongly adsorbed species (or ad-species containing sulfur) created some closed space in the zeolite pore structure.

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The acid properties, the steaming durabilities, and the catalytic activities for methanol conversion were investigated on various ferrialuminosilicates with different Si/Al ratio and Si/Fe ratio, aluminosilicates with different Si/A1 ratio, and ferrisilicate having MFI structure. Pyridine TPD showed that the amount of strong acid sites inc reased with increase of iron and aluminium contents in the ferrialuminosilicates and that the acid strength of ferrialuminosilicates was weaker than that of aluminosilicates. The amount of strong acid sites increased with increase of iron and aluminium contents up to about 400 μ mol/g in the ferrialuminosilicates after steaming at 873 K for 18 h, and it was constant over about 400 μ mol/g of iron and aluminium. The ferrialuminosilicates containing about 200 μ mol/g of iron showed the high activities in the conversion of methanol to hydrocarbons even after steaming.

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Calcium sulfite hemihydrate crystals with various shapes and sizes were synthesized from calcium chloride and sodium sulfite by a metasilicate gel-growth method. The purpose of this study is to determine the optimum conditions for the crystal shape control. The effective factors for the crystal shape control was found to be pH and ionic product ([Ca²⁺] [SO₃^2-]) in the gel. Calcium sulfite hemihydrate was obtained in six kinds of shapes; three poly-spherical shapes at 5.5-6.6 of the initial pH in the gel, the poly-columnar shape at 6.5, the plate-particular shape at 4.8 and the poly-plate shape at 6.5, respectively. The change in the poly-spherical shape to the plate-particular shape was also observed. It is found that the preferable conditions for constructing the individual crystal shape were given by both the ionic product of [Ca²⁺] [SO₃^2-] and the initial pH in the gel.

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The chelate resins of malonic acid dihydrazides-formaldehyde series, such as MDH-FA, Et⋅ MDHFA and Bu⋅ MDH-FA, were synthesized by the polycondensation of malonic, ethylmalonic and butylmaionic acid dihydrazides (MDH, Et⋅ MDH and Bu⋅ MDH) with formaldehyde (FA), and the collecting ability for Mn²⁺, Co²⁺, Ni²⁺, Cu²⁺, Zn²⁺ and Cd²⁺ was investigated by the batch and column methods. The collecting efficiency for these metal ions decreased in the order of MDH-FA > Et MDH-FA > Bu⋅ MDH-FA. By the batch method, the collecting efficiency of metal ions on the MDH-FA and Et⋅ MDH-FA resins indicated the maxima values at pH 5.5-7.0 for Ni²⁺ and Cu²⁺, and at pH about 7.5for Co²⁺, and increased with pH for the other metal ions. When the aqueous solution of pH 5.5 containing each metal ion of about 10 ppm was flowed down from the upper part of column (10 mmφ x 40 mm)packed with the MDH-FA or Et⋅ MDH-FA resin, Cu²⁺ was almost completely collected, though the collection suffered a small contamination from Ni²⁺ and Zn²⁺. On the other hand, the MDH-FA resin was able to collect the metal ions of six kinds with the collecting efficiency more than 85% from the aqueous solution adjusted to pH 7.8.

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In our previous work, during summer in 1989, the methane concentration in the soil at 80 cm in depth at 332 sites was investigated in the Tokyo metropolitan area. In this study, the emission rate was estimated on the basis of the data by using numerical analysis. The numerical analysis was carried out on the assumptions that methane in the soil moved in a vertical-one dimension by advection-diffusion. The permeability coefficient and the diffusion coefficient of the soil in the artificial area and low ground area were measured by using the Osozawa's method. As a result, the steady state emission rates in these area were 5.74 x 10² g/m²/y in summer and 11.5 g/m²/y in winter. It has been estimated that the methane emission rate in the Tokyo metropolitan area ranged from 84 to 150 Gg/y. The artificial area and low ground area where the permeability coefficient and the diffusion coefficient in the soil were investigated has an area of about 3.97 x 10⁸ m². The emission rate from these area was estimated to be about 4.57 228 Gg/y, suggesting that the methane production in the soil is one of the important source in the Tokyo metropolitan area.

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Decomposition of p-chlorophenol (p-CP) was carried out at 150deg; C under an oxygen pressure of 0.3MPa in aqueous solutions, and the effect of noble metals supported on alumina or titania was studied. The decomposition of p-CP was accelerated by the addition of all the catalysts except silver. The activites of the catalysts were in the order of Pt>> Pd > Ru > Rh > Ag. In the case of 5 % platinum supported on alumina, the conversion of p-CP and reduction in TOC after 30 min were 90% and 89%, respectively, indicating that p-CP was mainly decomposed to give carbon dioxide and water.
The effects of the platinum supported on various titania on the decomposit ion of p-CP and on the reduction in TOC were studied. The rate of the reduction was found to be higher on the catalyst with anatase-type titania than that with rutile-type one. We also found that the catalytic activity was increased with decreasing sizes of titania. By-products formed during oxidation of p-CP were mainly organic acids, such as maleic acid, malonic acid, acetic acid, and chloroacetic acid. Most of these intermediate products were further decomposed at a considerably high rate. The decomposition of p-CP was supposed to proceed via free radical reaction, as well as hydrolysis and decarboxylation.

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Attempts were made to apply thermally regenerable resins to the treatment of boiler-water containing divalent cations at a low concentration, as a promising substitute for the present technology, which requires periodical make up of chemicals for softening. Thermally regenerable resins were prepared for desalination of brackish water (3000 ppm NaCl) to a level of tap water, where multivalent cations were strongly bound on the resin and regarded as a cause to degenerate the column capacity. However, cyclic thermal regeneration of Sirotherm TR-10 has been demonstrated in the present work for a tentative standard condition of boiler-water of 0.001 meq/ml CaCl₂ (50 ppm as CaCO₃). Thus about half of the Ca²⁺ entrapped at 20° C on the fresh resin eluted on heating up to 80° C employing pure water for desorption, followed by the reproducible trapping of Ca²⁺ at 20° C for the next supply of 50 ppm Ca²⁺ in feed. A leak concentration as low as 5 ppm was attained for the heating-cooling cycles under a continued supply of water with 50 ppm Ca²⁺, where the resin capacity available for the reversible cycle was about 20% compared with that of the fresh resin.

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Propertis of the lignin and the lignin-carbohydrate complex obtained from steam-exploded Sugi wood were studied by use of a cylation. The lignin was acylated with acetic anhydride, palmitoyl chloride, and benzoyl chloride in p yridine at room temperature, and the acylated lignins had lower melting point and higher solubility in organic solvents than untreated lignin. Distribution of molecular weight of the acylated lignins was investigated by gel permeation chromatography (GPC). Based on the weight-average molecular weight determined, the number of phenylpropane units in the lignin was e stim ated as ca.6 to 10. A cetylation of the lignin-carbohydrate complex with refluxing acetic anhydride in t he presence of sodium acetete gave the partially acetylated product, from which cellulose triacetate depolymerized during the acetylation process was extracted with chloroform in a quantitative yield in accordance with the cellulose content of the lignin-carbohydrate complex.

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The deterioration of three way catalysts for the reduction of NO_x from the exhaust of natural gasfueled engine cogeneration systems was studied using the analyses of used catalysts and accelerated tests of trial catalysts which contain a variety of species and amounts of noble metals. The results show that the catalysts for gasoline-fueled automobiles do not have sufficient activity of methane oxidation after a couple of thousands hours operation, the window in which NO_x and CO are simultaneously converted shifts to a rich air/fuel (A/F) ratio, though the window still exists. This means that NO_x is not removed at the controlled A/F ratio. The results of the tests using artificially deteriorated catalysts clarified that the deterioration is caused by the sintering of noble metals. Further, from the experiments varying species and amounts of noble metals, it was also proven that Pt plays an essential role in methane oxidation and that the shift of the window can be suppressed by maintaining the surface area of Pt with increases in Pt amounts and in the Pt/Rh ratio. Besides, the increase in Pt amount contributed to an increase in the oxygen storage capacity of the catalyst due to CeO₂ and enabled operation under dynamic A/F control for a long time.

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We have developed the principle of vapor lubricants and raised it up as the new technology for the problem appearing frequently in small power motors. This paper deals with the mechanism of how and why the vapor lubricants give rise to (an) excellent performance. The following conclusions have been obtained mainly on the base of [1 to 1 adduct propylene oxide (PO) and HG]. (1) Lubricants can keep in vapor condition for over a few years. (2) Easy burning of lubricants is caused by tertiary carbon of PO and HG in their molecular structures. (3) Once the contact surface is covered by the lubricant film, the adsorption of undesirable organic silicone vapor is inhibited and the Si0₂ powder formation of insulation material is prevented. (4) Lubricants can't easily degrade for a long time.

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Concentration dependence of aggregates of copper chlorophyllin (Cu-chin) molecules in ethanolwater mixed solvents has been investigated by ESR and vaper pressure measurements. Cu-chin exists as oligomeric species in low ethanol concentration (5%) while it forms monomeric one in high ethanol concentration (75%). The vaper pressure measurement showed that the aggregate exists in dimeric form in dilute aqueous solution ( < 1 mmol dm^-3), and in polymeric form (degree of polymerization = 7)in higher concentration.

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In order to develop biocompatible materials, many workers have studied on conjugation of gelatin with synthetic polymers, for example, by graft polymerization of vinyl monomers onto gelatin in aqueous solution or by dry-blending of gelatin powder with synthetic polymers.
So, it was tried to esterify carboxyl groups of the aspartic and glu tamic acid residues of gelatin with a functional alcohol, and a reactive gelatin modified with allyl ester groups was newly obtained by chlorotrimethylsilane mediated reaction of gelatin and allyl alcohol. The degree of esterification was found to be determined by the ¹HNMR spectroscopy.
The resulting allylated gelatin wa s proven to cause graft polymerization through its allyl groups with styrene monomer by the action of radical initiator in an organic solvent to result in a gelatin/synthetic polymer conjugate.

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The protecting effect of dithiolatocobalt (III) complexes of the type [CpCo (S₂C₂X₂)] (M) against photodegradation of a cyanine dye 1'-buty1-1, 3, 3, 3', 3', 5-hexamethyl-2, 2'-benzo[e']indodicarbocyanine perchlorate (D) was studied in a t hin layer film system for digital recording and in an acetonitrile solution for the mechanistic examination.
The dithiolatocobalt (M) show much higher protecting effect than bis (benzene-1, 2-dithiolato) nickel complexes which are used industrially.
The protecting effect of d ithiolatocobalt complexes is due to the quenching of the excited triplet state of D as well as due to the quenching of singlet oxygen.

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