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As for plants, higher operation temperature is required so as to attain higher efficiency.The plant construction material requires not only good mechanical property at higher temperature but also better oxidation resistantce. It has become difficult to satisfy these requirements simultaneously by a single bulk material.One of the countermeasures is surface treatment such as PTA (Plasma transferred arc weldinhg), CVD (Chemical vapor deposition), PVD (Physical vapor deposition) and so on. Among surface treatment laser cladding is one of the outstanding methods because its higher power density enables to clad refractory materials or even ceramics. However, there has been little work on the oxidation behavior of laser clad NiCrA1Y layer.Therefore the oxidation behavior of laser clad NiCrAlY layer formed with single layer so as to take account of the influence of dilution from the substrate. Influence of Al content and heat treatment were also investigated.The results obtained are as follows;(1) The oxide formed on the NiCr10A1Y and NiCr20AlY clad layers was mainly α-Al2O3 and the growth rate of the oxide obeys parabolic rate law.(2) The parabolic rate constant of the NiCr10AlY clad layer is approximately the same with that of the bulk material, but that of the NiCr20AlY clad layer is larger by 1-2 orders of magnitude. The difference in parablic rate constant is caused by the formation of unstable faster growing θ-Al2O3 on NiCr20AlY clad layer at the initial stage of the oxidation.(3) The heat treatment makes the distribution of aluminum in the clad layer more homogenious which enhances the nucleation of Al2O3 at the initial stage of the oxidation, resulting in the lower parabolic rate constant.

Cetyltrimethylammonium bromide (CTAB) modified tobacco mosaic virus (TMV) virions so that the intrinsic fluorescence changed, viral infectivity decreased, sensitivity to RNase or UV irradiation increased, and coat protein subunits were released by the addition of Triton X-100. The change in fluorescence emission at 320 nm shifted to 340 nm was observed at 100 micrograms of CTAB per ml. This represents a change in the tryptophan environment inside the virion. At a lower concentration of CTAB, intersubunit contact was weakened, resulting in the release of coat protein subunits and an increase in RNase sensitivity. The release of coat protein took place gradually and two relatively stable intermediates were observed. Increase in UV sensitivity was observed at a lower concentration of CTAB and formation of pyrimidine hydrate was involved in this inactivation. The nature of the minor structural change leading to UV inactivation is discussed.

Vapor-phase catalytic reaction of pseudocumene with methanol has been studied by flow method using silica-alumina catalyst modified with nineteen kinds of metal salt.The silica-alumina catalyst containing 3.5wt% Ag showed the best result. The conversion of pseudocumene was 34% and the selectivity to durene and tetramethylbenzenes, 34% and 62%, respectively under the optimum reaction conditions: reaction temperature, 250°C; molar ratio of H2/(pseudocumene+methanol), 0.5-2.0; pseudocumene/methanol, 2.0; LHSV, 1.0hr-1.Rate of reaction increased in the presence of hydrogen. The activity of the catalyst became constant after three-hours' run, and the catalyst could be regenerated by heating in the air at 600°C for three hours.Disproportionation of trimethylbenzenes to xylenes and tetramethylbenzenes, and isomerization of xylenes, trimethylbenzenes, and tetramethylbenzenes occurred in addition to methylation of pseudocumene under these reaction conditions.

シクロヘキセンをステアリン酸コバルトの存在下, 60℃ 常圧で酸素酸化し, 酸化生成物について検討した。主酸化生成物は2 -シクロヘキセン-1-オン, 2-シクロヘキセン- 1 - オール, および(C6H9～10O2)2 で表わされる高沸点ペルオキシドであり, その他シクロヘキセンオキシドおよび少量ずつのシクロヘキサン, ベンゼン, シクロヘキサノール, シクロヘキサノンが同時に副生した。なお,2-シクロヘキセン-1-オールの赤外吸収スペクトルは未だ報告されたことがないが,これを求め,2-シクロヘキセン-1-オンの赤外吸収スペクトルはSadtler Standard Spectra記載のものは誤りで,DMSカードのものが正しいことを確かめた。

A kinetic study of the hydrogenation of maleic anhydride and intermediates using nickel-rhenium catalyst supported on kieselguhr has been carried out in order to investigate the activity of this catalyst on each reaction step and its effect on the reaction mechanism.It has been shown that this catalyst not only resists corrorsion by the organic acids such as maleic acid, succinic acid, propionic acid and butyric acid under the co-existence of water, but also directly promotes hydrogenation of maleic anhydride to tetrahydrofuran.The kinetic studies were done for each of the reaction steps involved in this process, and the orders and the rate of constants of these reaction steps were obtained. Especially, from the kinetic study of hydrogenation of succinic anhydride to γ-butyrolactone it is clearly noted that succinic acid and water are the strong inhibitors.There are three main reaction paths in this process as follows: "via γ-butyrolactone">"via polyester">>"via succinic acid".