Petroleum contains various kinds of heterocyclic organosulfur compounds refractory to conventional hydrodesulfurization. Several mesophilic and thermophilic bacteria, which are capable of cleaving efficiently carbon-sulfur bonds in dibenzothiophene as a model compound, have been isolated. When these desulfurizing bacteria were used for treatment of light gas oil previously processed through hydrodesulfurization, the refractory organosulfur compounds in the oil phase clearly decreased. Moreover, the thermophilic desulfurizing bacteria was found to be able to release sulfur atoms as sulfateion and leave the monohydroxylated hydrocarbon moieties intact on attacking dibenzothiophene and its various methylated derivatives at temperatures up to 60 °C.

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Structure and surface acid properties of η- and γ-aluminas chlorinated at high temperature were characterized using XRD, SEM, IR, XRF and XPS. When the aluminas were treated in Cl₂ and HC1 gas, transformation from η- or γ-phase to θ- and α-phases drastically occurred. Especially, cubic α-alumina crystallite particles of 2.0-2.5 μm were formed by the treatment with HCl (93 kPa) at 1273 K. The transformation was promoted in the presence of Na as bulk impurity.
In the IR absorption band of vibration of pyridine-ring on the aluminas chlorinated in chlorine (11kPa), only four peaks were assigned to pyridine molecules coordinated on Lewis acid sites, and shift ed to the high frequency by 5 cm^-1. The intensity of the 19b mode peak after outgassing at 773 K for 30min showed a maximum value at 973-1123 K, which was beyond two times that of the sample treate d in vacuo at the same temperature. Correlation was also established between the intensity of the 19b mode peak and the amount of chlorine on the surface.
It was suggested that the chlorine atoms bonding to aluminium cation (2.1 atoms nm^-2) promoted Lewis acidity strength of the nearest aluminium cations and the binding energies of Na, Si and Ti as bulk impurity corresponded to their oxide forms, of which the total amount did not exceeded the number of lattice defects in γ-alumina spine' structure.389

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The structures of (NH₄)_xH_3-xPW₁₂O₄₀ catalysts prepared by a homogeneous precipitation method using (NH₂) ₂CO in aqueous solution were studied in comparison with the structures of catalysts prepared by the conventional titration method using ammonia water. As for the samples prepared in a heated aqueous solution, i. e. by the homogeneous precipitation method at 383 K and by the titration method at 368 K, SEM, XRD, and BET measurments showed that nanocrystallites of (NH₄)_xH_3-xPW₁₂O₄₀ self-assembled to form dodecahedral aggregates for a wide range of x. In the cases of x<2 in these methods, large H₃PW₁₂O₄₀·nH₂O particles were formed on the outer-surface of the aggregates of (NH₄)_xH_3-xPW₁₂O₄₀, keeping a moderately high surface area and therefore a high catalytic activity even at x= ca.1.5. On the other hand, for the titration at 298 K, epitaxial connections between nanocrocrystallites were little formed and the surface area was very small for x≤2.0, similarly to the case of Cs_xH_3-xPW₁₂O₄₀. The differences between the two methods were explained by the different deposition processes of soluble H3PW12040 on (NH₄)_xH_3-xPW₁₂O₄₀.

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Catalytic combustion of particulate matter (PM) in Diesel engine exhaust gas has been examined using various titanium (IV) oxide supported catalysts. A copper catalyst (Cu/TiO₂ (Cl)), especially derived from copper (II) chloride, showed an excellent combustion activity among these catalysts, although most of catalysts increased their combustion activities by use of chlorides as starting materials. XRD analyses revealed that the formation of copper (II) chloride hydroxide (CuCl (OH)) is essential for the generation of active sites containing chlorine species. This means that the formation of the active chloride species composed of copper species will assist to promote the emergence of active oxygen species. The copper catalyst effectively worked under a simulated Diesel engine exhaust, suggesting that the active species are not so much poisoned by SO_x. Since the PM combustion was not affected by the presence of SOF (Soluble Organic Fraction) and the soot seemed to be an amorphous carbon, the ignition of solid by solid catalyst has to occur for the combustion, indicating that the key is the close contact of oxygen species activated on the catalyst with PM and the active structure containing chlorine species is essential for the development of new catalysts.

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Activity of TiO₂ based catalysts on the NO₂-NH₃-O₂ reaction was studied in the temperature range of 150-420 °C. The formation of NH₄NO₃ in the presence or absence of the catalysts has also been investigated. The following activity order was obtained at 250 °C.
Cr>Mn>Co>Pt>>Cu, Fe, Ce>V>Mo>W
Durability test for continuous NO₂-NH₃-O₂ reaction over V₂O₅-TiO₂ and Cr₂O₃-TiO₂ catalyst was carried for 20 hours at 250 °C. V₂O₅-TiO₂ catalyst lost its activity drastically after 4 hours mainly by the formation of NH₄NO₃. On the other hand Cr₂O₃-TiO₂ catalyst maintained the initial activity and the accumulation of NH₄NO₃ was negligible.

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Transparent perovskite (CaTiO₃: orthorhombic system) crystals were grown from a KF flux by a slow cooling method. The solubility of CaTiO₃ in KF increased with increasing temperature. At 1100 °C, CaTiO₃ had a solubility of about 7.3 mol%. The eutectic temperature was 835±5 °C. The crystal growth was conducted by heating mixtures of solute and flux at 1100 °C for 5 h, followed by cooling to 500 °C at a rate of 5 °C h^-1. CaTiO₃ crystals of sizes up to 3.9 mm were obtained from high-temperature solutions containing 4-15 mol% solute. The grown crystals were light blue or brown. The crystal sizes were dependent on the solute content. The most suitable solute content was 7 mol%. The basic form of the crystals was a hexahedron bounded by the {100}, {010}, and {001} faces. In certain instances, the {110}, {101}, and {011} faces were observed on the hexahedron crystals. The lattice parameters observed were a = 5.445 ± 0.002 Å, b= 7.649 ± 0.002 Å, and c= 5.383 ± 0.002 Å. The density was 4.02 ± 0.02 g cm-3. No phase transitions were observed for CaTiO₃ crystals in the range of room temp erature to 1100 °C on the basis of DTA data. The color of crystals became pale yellow or colorless on heating in air at 1100 °C for 24 h. Butterfly twins of CaTiO₃ were not grown from the KF flux.

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The C₃-symmetric tripodal ferrichrome model that contains three MeCON (OH) (CH₂)₂CONH sidechains attached to the smaller rim of α-cyclodextrin (α-CyD) as the rigid platform has been prepared and its structural features have been investigated by UV- and CD- spectroscopy. The linking of the side-chains to the CyD results in a twisting of the octahedral chromophore around the Fe³⁺ center, giving a Δ-cis, cis complex in water with a right-handed screw propeller, but the chirality is found to decrease with decreasing solvent polarity. Meanwhile, the binuclear tripodal complex with three MeCON (OH) (CH₂)₂ CONH(CH₂)₂ CON(OH) (CH₂)₂ CONH side-chains exhibits a significantly different solvent effect. The origin of the chirality will be discussed.

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The adsorption mode of lecithin (dioleoylphosphatidylcholine) or [3- (methacryloyloxy) propyl] trimethoxysilane (MPS) onto barium ferrite magnetic particles has been investigated by measurments of changes in solution concentration of the surfactant. Both adsortion isotherms of the surface active reagents on barium ferrite particles indicated to be of the Langmuir type. The occupied areas per one molecule on the surface of barium ferrite particles were estimated to be about 70 Ų/molecule for lecithin and 22 Ų/molecule for MPS at their saturated adsorption. In X-ray photoelectron spectroscopy (XPS) measurements for the adsorbed lecithin layer, the peak position in the binding energy distribution for the P (2p) photoelectron was observed to shift into slightly higher values with increasing amount of adsorbed lecithin. This implies that dipole-dipole interactions among the lecithin molecules become stronger because of increased high molecular packing in the adsorption layers. However, the peak position for the Si (2p) photoelectron remains almost unchanged due to slight interaction among the adsorbing functional groups onto the particles.

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This paper discusses the influence of KCl on the hydration of alite, that is a main component of ordinary Portland cement.
The amoun t of KCl addition was changed from 0 to 10% (counted by Cl). Heat liberation of the early hydration of alite with or without KCl were measured by conduction calorimeter. The rate of heat liberation of alite was accelerated by the addition of KCl. When the amount of KCl addition (counted by Cl)was 2 %, the hydration of alite was accelerated most. The induction period of hydration was reduced by the addition of KCl. But, the induction period of hydration of alite with KCl did not disappear like in the case of alinite hydration. The reaction ratio of alite was measured by XRD at late stage of the hydration. Th e reaction ratios of alite with 2 % KCl (counted by Cl) showed the maximum values, until the reac-ti on time 7 day compared with the case of other dosages of KCl. However, the reaction ratio of alite without KCl was showed the maximum value of 83% after 28 day. And the larger the amounts of KCl addition, the smaller the reaction ratios of alite.
The CaO/SiO₂ ratio of calcium silicate hyd rates produced by the hydration of alite with 2 % KCl(counted by Cl) was showed the maximum value until the reaction time 7 day. At the reaction time 28day, the ratio of CaO/SiO₂ of hydration products became large value with the amounts of KCl addition. Calcium silicate hydrates for the hydration of alite with KCl was contained chlorine. The larger the amounts of KCl addition, the bigger the Cl/SiO₂ ratio of hydrated products. When the dosage of KCl was 10% (counted by Cl), the ratio of Cl/SiO₂ of hydrated products was 0.29.

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This paper discusses the very early hydration of 12CaO·7Al₂O₃ glass containing Li20 compared with th at of 12CaO·7Al₂O₃ glass or 12CaO·7Al₂O₃ glass containing Na₂O or K₂O. These glasses were synthesized by fusion at 1500 °C and quenching. The hydration products of 12CaO·7Al₂O₃ glass containing 3mass% Li₂O were C₂AH₈ and lithium aluminate hydrate by XRD at very early stage. But the hydration product of others is produced only C₂AH₈. The heat liberation of various types of 12CaO·7Al₂O₃ glasses was measured by isoperibol calorimeter.12CaO·7Al₂O₃ glass containing 0.5 mass% Li₂O is the highest values of the heat liberation and the rate of heat liberation.
Therefore, because of its reactivity for hydration, 12CaO·7Al₂O₃ glass containing a small amount of Li₂O is to be expected as the new type of accelerator for cement and concrete.

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A technological process for decomposing nitrogen-containing compounds that exist in watercourse or marsh is strongly required to be established without delay to diminish the advanced eutrophy. In the present study, an electrochemical process to decompose aliphatic amino acids has been proposed in which amino acids are decomposed to CO₂, NH₃, acids and alcohols (not detected in the oxidation of glycine)in strongly alkaline solutions. Rate constant of oxidation of amino acids were evaluated from the potentiostatic oxidation, and the highest value was 8.94 x 10^-3 min^-1 for glycine and the lowest one 4.13 x 10^-3 min^-1 for isoleucine. In the oxidation at a constant current of 1.15 mA cm^-2, 1 mM glycine and arginine were almost completely decomposed within 60 min, but the electrolysis time longer than 120 min was necessary to completely decompose isoleucine and leucine.

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Carbonylation of 2-butyne-1, 4-diols was found to be catalyzed by cationic palladium (II) complexes such as [Pd (MeCN) ₂ (PPh₃) ₂ ] (BF₄) ₂ to give fulgides in good yields under mild conditions. The reaction pathway is also discussed.

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