The mechanism of chemical wear of copper with n-hexadecane containing sulfur was studied. The influence of sulfur concentration, load and temperature on the chemical wear has been investigated. As the mechanism of wear is complex, the simplest possible reaction system was selected.
From this work, it is found that there is optimum sulfur concentration at which wear rate and friction coefficient are minimum. From observation of surface and wear particles, it is made clear that before and after the minimum, the mechanism of wear changes. In the less than minimum region, adhesive wear seems to be the main mechanism and in the higher concentration region, the mechanism of wear is mainly flaking of surface films. From the results of the electron diffraction analysis of films and elemental analysis of wear particles, the films are found to be mainly CuS. By EPMA analysis of sulfur concentration in surface films, the minimum is considered to be due to critical film thickness.

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The steam-reforming of n-heptane over the Ni-WO₃ catalyst was carried out under the total pressure of 1atm and at a reaction temperature ranging from 450°C to 500°C. Other reaction conditions such as feed rate and feed composition were also varied in a wide range.
The kinetic analyses of the experimental results give the following rate equation:
r=r_CO+r_CO2=kp_H2O/(1+K_CO2p_CO2+K_H2p_H2)=k_COp_H2O/(1+K_CO2p_CO2+K_H2p_H2)+k_CO2p_H2O/(1+K_CO2p_CO2+K_H2p_H2)
The activation energy for the over-all reaction was 28.1kcal/mol, and the activation energies for the CO formation and for the CO₂ formation were found to be 33.8kcal/mol and 10.1kcal/mol, respectively. An irreversible surface bimolecular reaction mechanism explains the rate equation, but the further details of the reaction mechanism remain unresolved.

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Isomerization of n-pentane was investigated mainly by pulse technique in the temperature range from 300°C to 420°C using zeolite Y catalysts in which park of the Na⁺ ions were exchanged by ammine complex ions of palladium or platinum. These catalysts were found to be more selective than palladium or platinum supported on silica gel for n-pentane isomerization to isopentane against hydrogenolysis. Particularly, on Pd/NaY catalysts no hydrogenolysis could be observed, and isomerization took place exclusively.
Isomerization selectivity of NaY catalysts containing Pd or Pt was, however, strongly influenced by pretreatment in a stream of air prior to reduction. Palladium or platinum in the zeolite catalysts which were pretreated in air at temperatures near 300°C and reduced at 450°C was so highly dispersed that X-ray measurement could not detect crystals of these metals. Such treatment enhanced hydrogenolysis activity and reduced isomerization selectivity. On the other hand, selective catalysts for isomerization of n-pentane were obtained by reduction of those NaY catalysts containing Pd or Pt which were pretreated at below 250°C or above 350°C. Reduction of the catalysts pretreated under these conditions formed relatively large sized crystals of Pd or Pt on the outer surface of the zeolite particles.
From the results, it was implied that isomerization over NaY catalyst containing Pd or Pt would be promoted by protonic acid sites which were formed in the reduction processes of transition metal-ammine complex ions to metals.

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By contacting gaseous deuterium with hydrogen-reduced (Ni, Pd and Pt) metal-Y zeolites at 300°C and 400°C, it was shown that these solids contained surface hydrogn readily exchangeable with deuterium. The catalytic behavior of these solids for reactions of p-xylene was found to be similar to that of partially decationated HY zeolite. These results suggest the existence of proton on the surface of these solids.

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The catalytic cracking of aliphatic mercaptans and sulfides on the silica-alumina catalyst were investigated by the use of a pulse reactor.
The cracking reactivities of aliphatic mercaptans and sulfides increase in the following order:
C₂H₅SH<n-C₃H₇SH<n-C₄H₉SH<i-C₃H₇SH<sec-C₄H₉SH
(CH₃)₂S<(C₂H₅)₂S<(n-C₃H₇)₂S<(n-C₄H₉)₂S
This order is also consistent with the order of the stability of alkyl carbonium ions produced from the corresponding alkyl groups. The linear relationship was observed between the logarithms of the apparent rate constants of the cracking reaction of aliphatic mercaptans and sulfides and the enthalpy change of formation of carbonium ion from the corresponding paraffins.
From these results, a hypothesis was proposed that the catalytic cracking of aliphatic mercaptans and sulfides on the silica-alumina catalyst takes place with the carbonium ion mechanism.

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The decrease in activity and deactivation of silver catalysts were elucidated by measurement of surface area, determination of surface residues by means of oxidative desorption and analysis of the plot of η vs p_i, where η is the degree of deactivation and p_i is the partial pressure of component i.
The decrease in activity due both to sintering of silver and the formation of some oxidized state of silver diminished within the first three hours. Another factor that decreased the activity was the formation of surface residues by adsorption of ethylene oxide. The formation of surface residues and adsorption of ethylene oxide were reduced in the presence of water, carbon dioxide and excess oxygen. The analysis of η vs. p_i gave some information as to the behavior of adsorption of oxygen, water and carbon dioxide on the catalyst.
Based on the results, a mechanism for the stationary activity of the catalyst has been suggested.

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A kinetic study for oxidation of ethylene was carried out using an integral reactor and a silver catalyst promoted by potassium sulfate under stationary state. Measurements were made under ordinary and higher pressures. Empirical rate equations were found to be:
r_C2H4O=k₁P^0.33C_C2H4C_O2^1/2-k₃P^0.24C_C2H4OC_H2O^-1/2
r_CO2=k₂P^0.32C_C2H4C_O2, where P is the total pressure, and k_i and C_i are the rate constant and mole fraction for component i, respectively.

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As is widely known, the BWR equation has been well applied to predict the mixture properties such as P-V-T relations, enthalpy and vapor-liquid equilibria. In the present study, it was applied to infinite dilution K-values and Henry's constants of carbon dioxide and hydrogen sulfide in the methane-n-octane mixture. The behavior of these nonhydrocarbons in paraffinic mixture is an important knowledge in natural gas process. As a result, the BWR equation was found to be successful by introducing a binary interaction parameter.

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Isooctenyl alcohols were prepared from hydrolysis of diisobutylene monochlorides which were obtained by chlorination of diisobutylene. Analysis and identification of diisobuylene monochloride and isooctenyl alcohol and hydrolysis of the diisobutylene monochloride to isooctenyl alcohol in the presence of alkalis and solvents were studied. The following results were obtained.
(1) Structures of the products were determined by the comparison of their IR and NMR spectra with those of authentic compounds. The diisobutylene monochloride contained 1-chloro-2-neopentyl-2-propene, cis-1-chloro-2, 4, 4-trimethyl-2-pentene, trans-1-chloro-2, 4, 4-trimethyl-2-pentene and 3-chloro-2, 4, 4-trimethyl-1-pentene, and the isooctenyl alcohol contained 2-neopentyl-2-propene-1-ol, cis-2, 4, 4-trimethyl-2-pentene-1-ol, trans-2, 4, 4-trimethyl-2-pentene-1-ol and 2, 4, 4-trimethyl-1-pentene-3-ol.
(2) Reaction conditions in the presence of alkalis were studied. Among the alkalis used, sodium carbonate, sodium bicarbonate and calcium hydroxide gave favorable results, and the optimum pH value was in the range of 8∼11. When a strong alkali such as sodium hydroxide was used, favorable results were obtained by keeping pH at 8∼10.
(3) DMSO was found to be one of most effective solvents in that the rate of hydrolysis was high and primary isooctenyl alcohols were obtained in high selectivity.
(4) The kinetic studies showed that hydrolysis of monochloride was of the S_N2 type.
(5) Examination of the product composition during hydrolysis in DMSO showed that secondary monochloride changed to primary isooctenyl alcohols by isomerization. The reaction path of four isooctenyl chlorides, which were contained in the monochloride, was discussed.

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Geophysical well log interpretation methods have able not only to calculate the porosity and the water saturation of the formation but also to perform the lithological analysis of formation materials. The methods of lithological analysis adopted at routine works in well logging are all indirect method which is based on the material balance equations composed with geophysical well log data and physical characteristics of the formation materials. But it is fact that many problems exist on these log interpretation methods, especially on the selection of reasonable value of physical parameter of formation materials for all cases of the formation.
Authors point out the problems of log interpretation methods used at routine works and discuss the usefulness of direct analysis methods of formation materials on the improvement of log interpretation.

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