In order to confirm the reaction mechanism for the previously reported ammoxidation reaction using SO₂, ammoxidation reaction of toluene and ethylbenzene using Br₂ as an oxidizing agent was investigated.
C₆H₅CH₃+NH₃+3Br₂→C₆H₅CN+6HBr+25.0kcal/mol
(1) Activated alumina (γ-Al₂O₃), diatomaceous earth and fused alumina (Alundum; α-Al₂O₃) catalyzed the reaction at lower temperatures by 130-140°C than that in the case of SO₂, and particularly γ-Al₂O₃ and diatomaceous earth were very active, but the activity of these catalysts rapidly decreased in the course of reaction, and benzylbromide instead of benzonitrile was formed over the decayed catalyst or at lower temperatures. The rapid decay of catalyst activity resulted from the deposit of NH₄Br crystal and carbonaceous matter over the catalyst surface. In the case of ethylbenzene benzylcyanide was produced together with styrene and benzonitrile. It was inferred that the formation of benzylcyanide in this case was due to far lower reaction temperatures than those in the case of SO₂.
(2) From the above experimental results and the theory of radical reaction by Semenov, the reaction mechanism was inferred as follows;
C₆H₅CH₃→Br•→HBrC₆H₅CH₂→Br₂→Br•C₆H₅CH₂Br→NH₃γ-Al₂O₃C₆H₅CH₂NH₂→Br•γ-Al₂O₃→HBrC₆H₅CN
NH₃→γ-Al₂O₃NH₃(ads.)→Br•→NH₂(ads.)→HBr→γ-Al₂O₃
where the route (1) is probably a main process. This mechanism is similar to that of the reaction using SO₂.

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The catalysis of bismuth sulfate in the liquid phase oxidation of hydrocarbons and the decomposition of tert-butyl hydroperoxide has been investigated. Bismuth sulfate exhibits catalytic activity in the oxidation of olefins, but it does not with non-olefinic hydrocarbons, and it also decomposes tert-butyl hydroperoxide only in the presence of olefin. The rate of oxidation is the first order with respect to the concentration of olefin and about one-half order with respect to that of bismuth sulfate. The decomposition rate of tert-butyl hydroperoxide is the first order with respect to the concentration of the hydroperoxide and of bismuth sulfate. The catalytic and thermal decomposition rates of tert-butyl hydroperoxide do not depend on the concentration of olefin, but the rates increase with the decrease of ionization potential of olefin. Electron donative olefins and bismuth sulfate seem to accelerate the heterolytic decomposition of hydroperoxides and to initiate the autoxidation of olefins.

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The vertical sweep efficiency of waterflooding in carbonate reservoirs and the associated relative permeability-saturation relationship were studied with a mathematical reservoir model. The model consisted of 30×25 or 15×10 cells, and the rock properties of each cell were characterized so that the model represented the cross section of carbonate reservoirs. A production well and an injection well were located on each side of the model, and seven cases of waterflooding performance were calculated with various distribution of reservoir rock properties. The performance was then compared with those predicted by three vertical sweep efficiency calculation methods, and it was concluded that the vertical sweep efficiency was best predicted by taking an average of the efficiencies by the two methods: a method based on the Buckley-Leverett displacement principle6) assuming a reservoir consisting of one layer, and the Stiles method5) with the above displacement principle using the smoothed permeability profiles determined by the Fourier series trend analysis. Meanwhile the Stiles method using the unmodified permeability profile of cells penetrated by the injection well gave very low vertical sweep efficiencies in many cases.
Investigation of the absolute permeability revealed that the geometric average of permeabilities of cells penetrated by the wells was almost as large as the absolute permeability of the reservoir determined by the reservoir performance but the arithmetic average was greater, when the horizontal variation of the cell permeability was large, while the arithmetic average was as large as the reservoir permeability but the geometric average was smaller, when the horizontal variation was small.
It was also concluded that the relative permeability, which gives nearly 110% of the predicted vertical sweep efficiency if no truncation error is envisaged, should be employed in a large cell model with only one intermediate cell between the injection well cell and the production well cell, in order to compensate for an effect of truncation errors on the efficiency.

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The purpose of this study was to determine how the aging of asphalt in actual pavement in service for three years varied with depth below the pavement surface and transverse distance from the pavemenet side. Then the properties of recovered asphalt from the core were observed with gel permeation chromatography, infrared-spectroscopy, and chromatographic fractionations. The following results were obtained:
1) The density of core increased toward the center line with traffic roads, and the penetration of asphalt recovered from the core corresponded to tendency of the core density.
2) Properties of recovered asphalt greatly depend on the depth below the pavement surface, and the hardening and oxidation of asphalt rapidly proceed in the depth 0-0.5cm below the pavement surface. This phenomenon is more clarly seen in the side of pavement.
3) The asphalt in the upper section-i.e. 0-0.5cm below the pavement surface-shows remarkable deviation from the linear relation between the extinction coefficient of carboniumbond and the reciprocal of penetration observed by thin film and rolling thin film oven tests, but the asphalt in the lower section shows a good agreement with the linear relation.

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Separation of m, p-xylenes by selective trans-tert-butylation of m-xylene was studied. Mole fractions of each components in equilibrium in the reaction of m-xylene with tert-butylalkylbenzenes were determined and the equilibrium constants were obtained. They are, 4.34 for di-tert-butyltoluene, 0.29 for tert-butyltoluene, 0.48 for di-tert-butylbenzene and 0.11 for tert-butylbenzene. Di-tert-butyltoluene was found to be suitable for the separation of m, p-xylenes, and 98% pure p-xylene was obtained from mixed xylenes (m:p=2:1) by the three-stage transalkylation reaction.

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