Epoxidation of olefins by molecular oxygen was developed by combining aldehyde with a catalytic amount of nickel (II), iron (III), vanadium (IV), and manganese (II) complexes containing 1, 3-diketonato ligands. The efficiency of catalysts was improved by designing the structure of the ligands, and various olefins, styrene derivatives, and α, β -unsaturated carboxamides were oxidized to the corresponding epoxides in high yields. It was also revealed that the stereofacial selection of cholesteryl derivatives in the aerobic epoxidation was different from that of the conventional epoxidation using peroxy acids, such as mCPBA or peracetic acid. Novel manganese (III) complexes having optically active 1, 3-diketo-type ligands, N, N'-bis (3-oxobutylidene) diamine derivatives, were designed and synthesized on the basis of the characterization of X-ray analysis. In the presence of a catalytic amount of these manganese (III)complexes, enantioselective and aerobic epoxidations of unfunctionalized olefins were achieved by the combined use of molecular oxygen and pivalaldehyde, and the corresponding optically active epoxides were obtained with good-to-high enantiomeric excess. It was found that the absolute configuration of the resulting epoxides was reversed by the addition of N-methylimidazole. Based on these observations, the key intermediates in the present aerobic epoxidation were tentatively proposed to be acylperoxomanganese complexes.

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The propagators of the chain and the ring molecules with same molecular units are expressed in terms of trigonometrical functions. These expressions are convenient to practical calculations of several quantum chemical quantities. For exercises, the charge density of the chain and the ring molecules with same diatomic molecular units are calculated.

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A potentiometric hydrocarbon sensor which consists of a single comaprtment cell has been constructed using a high temperature proton conductor as a solid electrolyte. A sensor element, Pd | CaZr_0.9In_0.1O_3-α | Au, gave stable EMFs for methane, ethane or propane in air at 700° C. The 90% response time was less than 10 s, and the relationship between EMF and hydrocarbon content was almost linear. The sensing mechanism was based on a steam concentration cell, which resulted from the difference in combustion activity for hydrocarbons between the two electrodes.

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The ratio (R) of the amount of CO per the total amounts of CO and CO₂ from the TPD (temperature programmed desorption) profiles in an helium stream after CO admission were compared among variously-pretreated MgO. R was sensitively changed by the starting materials and pretreating atmospheres; hydrated MgO, Mg (OH)₂originating MgO showed larger R than reagent MgO, and helium-pretreated MgO larger than hydrogen or oxygen-pretreated MgO. These results were ascrib ed to the difference of the properties of two pararell reactions in relation with the degree of coordinatively unsaturation (d. c. u. ) of the surfaces. CO cluster formation proceeded preferably on the sites of higher d. c. u. than the Boudouart reaction did. R was thus suggested to be available as a parameter to evaluate d. c. u. of the surfaces.

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Addition of barium to automotive Palladium three-way catalyst has been found to be effective for improvement of NO_x reduction activities. Additive effects of Ba to Pd/γ -alumina catalyst were revealed by NO_x reduction using simulated exhaust gases, chemisorption of reaction gases, water gas shift reaction, steam reforming reaction and propylene oxidation. Remarkable improvement in the NO_x reduction activities by the addition of Ba were recognized both (1) in the temperature range of 100 to 500° C under stoichiometric simulated exhaust gas and (2) under reducing conditions of the simulated exhaust gas. The roles of Ba were concluded as follows: (1) Under the stoichiometric simulated exhaust gas, the enhancement of NO chemisorption by the addition of Ba led to the selective reduction of NO rather than O₂. (2) Under reducing conditions of the simulated exhaust gas, the suppression of chemisorbed hydrocarbons (propylene etc.) on Pd by the addition of Ba allowed the NO_x reduction to proceed smoothly.

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The residual strain in epitaxially-grown PbTiO₃ and PZT films prepared on (100) MgO substrates by CVD was observed by X-ray diffraction. The lattice parameter ratio of c-axis to a-axis (c/a) in film was smaller than that of the powder. This is caused by the thermal strain owing to the thermal expansion difference between the film and the substrate below the Curie temperature. The large expansion of c -axis and shrinkage of a-axis of the film comparing with that of the substrate under the cooling process below the Curie temperature made the large strain in the film. On the other hand, the nonuniform strain in the film was also larger than that of powder. This is thought to be originated to the gradient of the lattice parameters along the film thickness.

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In order to clarify the swelling characteristics of fluorine micas, swelling pressure accompanied with absorbing water was measured with load cell for powder compacts of Li-taeniolite [LiMg₂Li (Si₄O₁₀)F₂], its Ge-substituted analogue, and Na-taeniolite series micas [Na_xMg_3-x, Li_x (Si₄O₁₀)F₂] (x= 1. O-O.4). Swelling pressure, generated by absorbing water into the powder compacts of 0.30 g with the sample cell volume being restricted, attained to its equilibrium value in about 10 h. This equilibrium value, i. e., swelling pressure (MPa) increased with decreasing porosity of powder compacts as well as the amount of absorbed water (wt%) at its equilibrium. This can be explained in terms of the degree of expansion of basal spacing (d₀₀₁) because the expansion depends on the porosity of the specimen, i. e., the free space for water uptake, indicating the intimate relation between the porosity and the amount of water molecules intercalated into the interlayer region. Thus the swelling pressure was lower when the amount of water absorbed was larger since the basal spacing was fully expanded to be stable, revealing little residual swelling potential. This leads to the conclusion that swelling characteristics of various fluorine micas having different swelling characteristics should be compared by the swelling pressure (MPa)or reduced swelling pressure (MPa/mmol) at the normalized conditions, i. e., at the same amount of water absorption. Based on these normalized conditions, it was clearly shown that Li-taeniolite had larger swelling pressure than its Ge-substituted analogue although both micas had free swelling properties. It was also shown that the Na-micas having limited swelling (two-layer hydrated type) had the smaller swelling pressure than the Na-micas having free swelling properties. These facts suggest that the swelling pressure is a useful parameter to describe the swelling characteristics of fluorine micas.

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Dipivaloylmethanato (dpm), acetylacetonato (acac), and ethyl acetoacetato (etac) complexes of bismuth(III), strontium (II), and calcium (III) with a high purity as a precursor to BSCCO superconducting oxide were prepared. Bismuth complexes were obtained by the reaction of bismuth trichloride with Hdpm in the presence of triethylamine or by the reaction of bismuth triethoxide with Hacac and Hetac. On the other hand, strontium and calcium complexes were prepared by the reaction of metals with the ligands. The solubilities and spectral analyses of these complexes were investigated.

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Polymethylbenzophenones (1a1j) reacted with fuming nitric acid in acetic anhydride to give 2-(nitromethyl)polymethylbenzophenones (2a-2j) in satisfactory isolated yields. Compounds 2a-2d underwent the intramolecular nucleophilic substitution/cyclization by equimolar amount of 1, 8-diazabicyclo[5.4.0]undec-7-ene and subsequent oxidation by KMnO₄ in MeOH/CH₂Cl₂ or by Na₂Cr₂O₇ in AcOH to afford the corresponding polysubstituted anthraquinones (3a-3d) in good isolated yields. Comounds 2e-2j underwent the intramolecular vicarious nucleophilic substitution of hydrogen/cyclization by 2 molar amounts of Na₂CO₃ in acetone and subsequent oxidation by Na₂Cr₂O₇ in AcOH to give the coresponding polysubstituted anthraquinones 3a-3f.

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The degradation of several synthetic water-soluble polymers, such as poly (sodium acrylate) (PSA), poly ( sodium methacrylate) (PSM), poly ( sodium 2-ethylacrylate) (PSE), polyacrylamide, and poly(ethylene oxide), with L-ascorbic acid (ASA) was investigated in a phosphate buffer solution adjusted at pH 7 at 30° C under introduction of air of constant flow rate. The progress of degradation was monitored by the reduction of relative viscosity of the reaction system. All these polymers were degraded easily. The degradabilit y of the acrylate polymers increased in the order; PSE < PSA < PSM. The extent of consumption of ASA in these systems determined by the decrease in UV absorption based on ASA also increased in the order of PSE < PSA < PSM < control, so these polymers suppressed the oxidation of ASA. The initiation mechanism of the polymer degradation is discussed; ASA/O₂ generates hydroxyl radical during the oxidation process, and the hydroxyl radical abstracts hydrogen atom from the polymer at α -position of the substituent of the monomer unit, or the hydroxyl radical accepts one electron from the carboxylate anion to generate the acyloxyl radical followed by decarboxylation, especially in the case of PSM. The activity of ASA/O₂ in the polymer degradatio n was found to be significantly high as compared with commercial hydrogen peroxide. Thus, ASA/O₂ would be effective for waste polymer treating agent.

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Concentrations of atmospheric and rainwater organic acids such a sformic, acetic and oxalic acids in the Hiroshima prefecture, westem Japan, during 1993-1995 were determined by ion chromatography. Concentration ranges of formic and acetic acids detected in the ambient air were O-8 and O-12 ppbv, respectively and in rainwaters O-38 and O-24 μ M, respectively. Oxahc acid was detected only in rainwaters at the range of O1.5 μ M. The percentage of free acidity (hydrogen ion concentration) generated from organic acids to that from the total acidic substances (inorganic and organic acids) was 8.0% in average with a range of 3.5-15.1%, implying that organic acids contribute to the acidification of rain. Measurements of organlc acid concentrations in car exhausts and combustion gases of incinerator were carried out to evaluate the role of anthropogenic activities in the production of atmospheric organic acids. The results indicate that these fossil fuel combustion gases contain from ppbv level to hundreds ppbv level of formic and acetic acids.

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The effective methods for extraction and removal of heavy metal ions from an anaerobic sludge were investigated. Extractability of heavy metal ions was increased by the conversion of the anaerobic sludge into an aerobic sludge. By the addition of acid (pH 2) or ligands (pH 7), heavy metal ions such as Cu²⁺, Cd²⁺, Pb²⁺ and Zn²⁺ were extracted from the aerobic sludge in a 50 100% yield and metals extracted with acid were easily recovered by the adoption of neutralization method but less recovered with cation exchange resin. The e lectrolytic method can be favorably used to remove metal ions in solution also when both ligands and suspended solid are present. In order to carry out extraction and recovery of metal ions at the same time, the aerobic sludge suspension was electrolyzed at pH 2 and 6 in the presence of NTA. In this method, metal contents in aerobic sludge were reduced to below 15% except for Pb²⁺ at pH 2 after 7days and recovery of metals on electrode was over 80% in the presence of NTA. When the anaerobic sludge suspension was treated in a similar manner with forced aeration, metal contents were reduced to below 25% except for Cd²⁺ and over 60% of metals were recovered.

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The reaction of benzo[b]cyclohept[e][1, 4]oxazine (1) (0.26 mmol) with m-phenylenediamine (2)(0.31 mmol) in 1-BuOH (1 ml) under argon at 80° C for 48 h gave two major tropopodands; Namely, 10 (3-aminophenylamino)benzo[b]cyclohept[e][1, 4]oxazine (3) (Y=38%) and 3 (3-aminophenylamino) -2-phenylaminotropone (4) (Y = 29%). Moreover, the above reaction in the presence of Ni (OAc)₂ · 4 H₂O (0.25 mmol) at 80°C for 24 h afforded two Ni(II) complexes 5 (Y = 5%) and 6(Y ≥ 84%) of the products 3 and 4, respectively. The structures of the products were established on the basis of their spectroscopic (UV-vis, MS, IR, and NMR) data. Possible reaction pathways for the formation of these compounds are discussed.

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The cross-coupling reaction of the Grignard reagent with alkylating reactants (RBr, RI, and ROTs)was carried out in the presence of copper (II) acetate and organic copper (II) complex catalysts (0.01- 0.05 molar amount) in tetrahydrofuran. The reaction readily gave higher hydrocarbons (n-C₁₇H₃₆, n-C₂₃H₄₈, n -C₂₆H₅₄, n -C₂₇H₅₆, n -C₂₉H₆₀, n -C₃₀H₆₂, and n-C₃₁H₆₄ ), 1 - phenyloctadecane, and 1-cyclohexyloctadecane as the desired products in 90 99% isolated yields under mild conditons (-10-60° C, 2 -5h). In particular, copper (II) acetate was found to be much more effective than con ventional inorganic copper (II) salt catalysts (Li₂CuCl₄, CuX₂) from the viewpoints of availability, solubility, stability, and activity.847

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The new anti-microbial material was obtained by the reaction of silver acetate with sodium sulfite and sodium thiosulfate. From the following facts, it was suggested that the product was composed of thiosulfato silver complex; the facts were drastic change of solubility during the procedure, observation of no responce of the solution with chloride ions, no sensitivity to the silver-selective-electrode of the solution containing the product, and also estimation of the numbers of dissociated ions in the solution of the complex through the process of electric conductivity measurements of the solution.

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