Streaming dichroism of aminoanthraquinone disperse dyes, 1, 4, 5, 8-tetraamino-, 2, 3-diaminoand 2-aminoanthraquinone, solubilized (1.0-4.2 x10-4 mol/i) in 25% aqueous solution of poly(oxyethylene) (average degree of polymerization is 9.3) dodecyl ether, has been measured to investigate their modes of solubilization in the micelles of nonionic surfactant. It was demonstrated experimentally that 1, 4, 5, 8-tetraaminoanthraquinone was solubilized in the hydrophilic moiety of the micelles, facing the longer axis of the molecule in the direction of the cylindrical axis of micelle as possible. On the other hand, the 8-substituted ones, 2, 3-diamino- and 2aminoanthraquinone, were proved to be solubilized in the hydrophilic moiety of the micelles, the longer axis being nearly perpendicular to the micellar axis. Especially, it was inferred that the latter was solubilized lying somewhat more horizontally with increasing velocity gradient.

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The diffusion coefficient (D) of an electrolyte in agar gel was obtained by measuring change in the electrical conductance of the gel with the electrolyte diffusing in a cell shown in Fig.1. The D-values decreased gradually with the incease of the concentration of the diffusing solute between two electrodes for the conductance measurement. The values varied linearly with time. The characteristic diffusion coefficient (De) was determined by the extrapolation of the D vs. time line to time zero. The D. probably corresponds to the diffusion coefficient in a solution in infinite dilution. Therefore the D. obtained for the gel containing the electrolyte, before the diffusion experiment is probably the differential diffusion coefficient in the concentration of the electrolyte in gel before the diffusion experiment. De was found to be independent of the concentration of diffusing solute. D. of KCl in 0.5 g/100 cms agar gel at 25°C was measured with thirteen cells which have various distances (xE) from the top of a glass tube with the gel to the electrode (1-2 cm), and various diameters (4-8 mm). The De-values of KCl were in the range of (1.841-1.892) X 10-5 cm²/s.

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Hydrogen sorption by palladium sheet was investigated by measuring the sorption rate at the hydrogen pressure of 1 atm over the temperature range from 9°C to 60°C. The rate of hydrogen desorption from the 9-phase palladium sheet was also measured at 140°C to 310°C with the aid of a Pirani gauge. The amount of sorbed hydrogen was proportional to the square root of time. The sorption rate was independent of the thickness of the sheet (Fig.2). These results were analyzed by a model where the rate-determining step of the hydrogen sorption is a hydrogen-diffusion process in the 8-phase accompanying the a--q3 phase transition. The calculated values of the reduced diffusion coefficients were in good agreement with those obtained by different methods (Fig.8). The temperature dependence of the coefficient was expressed as Dp' (cm²/sec) =2.9 x 10-1 exp (-5460/R T). In the desorption process, there was an induction period, and after this induction period the amount of desorbing hydrogen was proportional to the square root of time (Fig.3), the desorption rate being independent of the sheet thickness (Fig.9). These results were explained by considering that the desorption process is controlled by two different processes, a phase transition process at the Pd surface and a hydrogen diffusion process in the ce-phase accompanying the phase transition in the bulk. The calculated values of the reduced diffusion coefficients over the temperature range from 140°C to 260°C were in agreement with those obtained by other measurements (Fig.11). The temperature dependence of the coefficient was expressed as Da' (cm²/sec) =3.0 x 10-8 exp (-5400/R T).

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Ultrasonic absorption spectra in aqueous or dioxane-water solution of formic acid were measured by the ultrasonic pulse method from 6 to 110 MHz, and ultrasonic velocities were measured by the interference of pulse wave and continuous wave at 5 MHz. Double relaxation absorptions were observed in 1 and 2 molar solution of formic acid and the cause of the relaxation appeared at a high frequency was inferred. The velum changes due to dissociation of formic acid, recombination, and dissociation rates were calculated on the basis of the ultrasonic absorption spectra, and compared them with the values obtained by other methods. The agreement between them was fairly good. Therefore, the ultrasonic absorption found in a high frequency would be attributed to the relaxation of dissociation equilibrium of formic acid in certain solution.

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The initial oxidation of the (100) plane and polycrystalline surfaces of iron at room ternperature has been investigated with a combined LEED-AES system. It was found that the oxidation reaction of Fe(100) clean surface in the 10-6 Torr of oxygen obeyed the linear law and Fe(100)-disordered-O structure formed. The heat treatment of this oxidized surface caused oxygen to diffuse from the surface to the bulk at the surface layers. The activation energy of the diffusion was 231 kcal/mol. A FeO(100)-like surface simultaneously formed below 550°C. The thickness of the surface layer was estimated to be about monolayer. The studies of the polycrystalline surface have shown the same results as those for the Fe(100) surface, except that the rate of oxidation at room temperature was slower and the activation energy of surface-to-bulk diffusion of the oxygen was 17--1 kcal/mol. This activation energy was smaller because of the diffusion along the grain boundaries. A FeO-like surface formed below 650°C. The Fe0-like surface was so stable that it was not destructed by heating up to 750°C and so inactive that it was not reduced by H₂ of 10-5 Torr and not by CO of 10-6 Torr., at higher temperatures up to 750°C as well.

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The surface acidities of heat-treated titanium(N) oxide sulfate and ammonium titanium(N) oxide sulfate were studied in connection with the surface acidity of titanium oxide prepared in the presence of sulfate ion. The amine titration and the catalytic dehydration of 2-propanol Were carried out for the determination of the acidity. The composition and structure of these compounds heated at various temperatures were also investigated by the use of chemical analysis, X-ray diffraction and IR absorption. The surface acidity of titanium(N) oxide sulfate became appreciable when this compound was heated at above 400°C, and attained a maximum at 550°C. A correlation was found between the acidity and the amount of dehydrated sulfate (TiOSO₄) formed by the heat-treatment. The existence of sulfonyl group was recognized in the range of temperature at which the sample has considerable amounts of acid (400-600°C). Besides Bronsted acid sites, Lewis acid sites were detected when the sample was heated in vacuo, although most of the sites converted to Bronsted sites in contact with water vapor. Accordingly, the vacant site of Ti ion activated by attached sulfonyl group may be the origin of the acidity. In the sample of ammonium titanium(N) oxide sulfate, ammonium hydrogensulfate formed when the sample was heated at lower temperature such as 250°C, and the existence of this compound and TiOSO₄ might be the cause of the solid acidity of the sample.

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Reactions between acrylamide and hydrogen in the presence of cyano(2, 2'-bipyridine)cobalt complex (Co-CN-bpy) were studied at 30°C and 1 atm of hydrogen pressure. (1) Only hydrogenation reaction of acrylamide proceeded when the molar ratio of acrylamide to Co-CN-bpy complex (acrylamide/Co ratio) was not more than 1. (2) Both hydrogenation and polymerization reactions occurred concurrently at the ratio, between 1 and 10. (3) Polymerization mainly proceeded when the ratio was above 10. The rate of the hydrogenation of acrylamide in the presence of Co-CN-bpy complex was expressed by the following rate equation. R=kCo-CN-bpy. J1-1AcrylamideT.9[E]0.5 The apparent activation energy of the hydrogenation was estimated to be 15.7 kcal/mol. The mechanism of the hydrogenation of acrylamide in the presence of Co-CN-bpy complex was discussed on the basis of these results.

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Vapor-phase oxidative dehydrogenation of isobutyraldehyde over Bi208-MoO^2- catalyst has been investigated with reference to the composition of the catalyst and to the reaction conditions suitable for the selective formation of methacrylaldehyde, and the nature of oxygen species participating in the reaction was elucidated. At 450°C, conversion of isobutyraldehyde, yield of methacrylaldehyde and selectivity to it were low when MoOs content was below 40 atom%, but they were markedly enhanced in proportion to MoO₃ content when its content was above 50 atom% and finally MoOs catalyst acted in the highest yield and selectivity (59.8 % and 72.9%, respectively). A similar tendency was also observed in the formation of maleic anhydride during the co-oxidation with furan, and gave evidence for the important role in the dehydrogenation due to the lattice oxygen of Bi2O^2- (MoO₃S 40 atom%) and Mo6+, --0 of MOOS (MoO50 atom%) through a redox mechanism. This mechanism was further supported by the following observations: (1) a close relationship existed between the yield of methacrylaldehyde and the amount of Mo'+ formed during the reaction over various Bi20, - MoOs catalysts, (2) the rate of methacryladehyde formation over MoOs catalysts, promoted with alkali metal oxides, increased with decreasing electronegativity of alkali metal ion added, and (3) bismuth metal (MoOs S 40 atom%) or MoO, (Moos z50 atom/) preferentially formed in the reduction of the catalysts with isobutyraldehyde. Thus, it was deduced that while abonded type lattice oxygen, -Bis+-O-Bis+, of Bi2O^2- served as a hydrogen eliminator from iso butyraldehyde, double bonded type one, Moe+.0, was much more effective for the dehydrogenation. The type of bonding between oxygen and metal ion showed a strong effect on the selectivity of dehydrogenation.

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To elucidate the chemical reactivity of the hydrogen atom absorbed in the hydrogenated alloy PrCo51-1, 1, the hydrogenation of ethylene was carried out over PrCo5H₂.4 in the absence (A) or presence ( B ) of hydrogen in gas phase. PrCo5112.4 was prepared from PrCo, according to an ordinary procedure with repeated heating and cooling in hydrogen atmosphere. The hydrogenation of ethylene was conducted at about 0°C in a conventional gas circulation system in a pressure range of ethylene 5--16 cmHg and of hydrogen 0--38.0 cmHg. The hydrogenation rate was followed by gas chromatography. In the case of (A), the total gas pressure in the gas phase remained constant during the reaction. The hydrogenation rate was independent of the partial pressure of ethylene and it increased in proportion to the concentration of the absorbed hydrogen atom. The rate of desorption of the absorbed hydrogen atom from PrCo5H₂.4 also measured under a reduced pressure. The desorption rate was approximately the same as the hydrogenation rate under the similar conditions. From these results, it was concluded that the migration process of the absorbed hydrogen atom from the bulk of the alloy to its surface was rate-determining. In the case of (B ), on the other hand, the hydrogenation rate was accelerated by the gaseous hydrogen; the rate increased almost linearly with increasing pressure of hydrogen. The hydrogenatial of ethylene was also conducted over PrCo, under the similar conditions.

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The 1-12--D2 equilibration was conducted on an intermetallic compound LaNi5H3.5 over a temperature range 5 to 96°C, and a mechanism for the equilibration was proposed. When only D2 was introduced to the catalyst at a temperature as low as 96°C, the equilibration hardly took place. However, the equilibration proceeded rapidly even at low temperatures when mixtures of H₂ and D2 were introduced. The observed initial rate of the equilibration over a temperature range 60 to 96°C obeyed Eq. ( 1 ), ko exp (-1.1 kcal/RT) pH 21-0.1D2-1, .0 ( 1 )where PH, and PD2 are the partial pressures of H₂ and D2, respectively, and ko is a constant. Eq. ( 1 ) suggests that the rate of the reaction is controlled by the adsorption process of H₂ on the catalyst surface almost completely covered with D2 molecules. As the catalyst was warmed up to 00°C, the reaction took place even when only D2 was introduced. The observed initial rate over a temperature range 5 to 10°C was expressed by Eq. ( 2 ), r=ko' exp(-7.4 kcal/RT) PD2-1'° ( 2 )Eq. ( 2 ) suggests that the rate of the reaction is controlled by the migration process of hydrogen atoms from the bulk of LaNi, Hs., to the surface almost completely covered with D2 molecules.

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In the catalytic combustion of town gas on some supported metallic catalysts, it has been found that the reaction rate changes periodically. This auto-oscillating phenomenon was studied by means of the continuous measurement of the surface temperature by using an infrared thermometer under varying reaction conditions and catalyst compositions; the mechanism of this phenomenon was discussed.The auto-oscillations was observed most evidently when a supported plate-shaped catalyst containing 1.8% Cu was used. In this case, the lower temperature limit of the oscillations gradually approached to the upper one (On) with increasing atmospheric temperature and consequently, the amplitude and the frequency of the oscillations decreased monotonously. A stationary oxidation continued when the fuel concentration was high; however, the oscillations occurred with increasing oxygen concentration, and the amplitude increased with increasing n. An influence of gas velocity on the oscillations was rather minor. The oscillations disappeared by the addition of small amounts of platinum metals to the 1.8 % Cu catalyst, or by the addition of copper itself, and the stationary oxidation occurred at on. The effect of addition was in the following order: RhPtRdCu. Moreover, the oscillations also disappeared when a very thin (80 g) platelet of Rh or Pt (catalyst) was put closely on an outer surface of the 1.8% Cu catalyst of 1.0 mm thick, and the stationary oxidation was obtained at a high temperature, at which the diffusion of reactant being a ratedetermining step. Even supported catalyst containing 0.001% Rh showed a sufficient effect. On the basis of these facts, it was considered that the auto-oscillations are the surface phenomena which arise from the comPlexing changes of mutual relations among the surface reaction rate, the adsorbed concentrations of oxygen as well as reductants, and the retardation of reaction due to the adsorption of the products.

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By considering material balances and effects of concentration ratio of hydrogen peroxide to chlorate, it was found that products of the reaction between chlorate and hydrogen peroxide were chlorine dioxide, chlorine and oxygen, and that amounts of chlorine was small as compared with others. The main reaction was represented by the equation (1), 2 ClOa" + H₂O^2- + 2 H⁺=2 ClO^2- + 2 H₂O + O^2- (1) The formation of chlorine could be explained by assuming that chlorine dioxide first disproportionate to chloride in the hydrogen peroxide solution and this chloride reacted with chlorate in sulfuric acid solution. The reaction rate was estimated to be first order for both Cl0, - and 112O^2- by measuring the change in absorbance at 360 nm. The perhydroxyl radical HO, was found to play an important role in this reaction by using p-nitrophenyl acetete and allylthiourea. Based on the assumption of the oxidation and reduction mechanism of hydrogen peroxide with metal ion proposed in the previous reports by Haber, Weiss, Baxendale, Saito and Stein, following equations were proposed as elementary reactions. H₂O^2- + H⁺=113O^2-+ (pK, , -- .7) kl Cl0 + H3O₂+=ClO^2- + H₂O + HO^2-. k-1 k2 HO^2-. + Cl0 + H⁺ ClO^2- + H₂O °2Experimental results favored the appropriateness of these derived equations.

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Diffusion profiles in Pyrex glass after exchange in molten potassium nitrate were obtained by secondary ion mass spectrometry and the chemical etching-flame photometric method over the temperature range 350.450°C (Figs.1, 3, and 4). The former method was applicable to the diffusion in the narrow region within 1, u of the surface. Secondary ion intensity ratios, I (39K+) r(28si+) and /(28Na+)//(28Si+), were proportional to atomic concentrations of potassium and sodium ions in Pyrex glass, respectively (Fig.2). The distortion of the profiles due to ion etching was negligible (Fig.3). The interdiffusion coefficients, which depended on potassium concentration (Fig.5), were described by an Arrhenius' equation D=8.2 X 10-4 exp (-26000/R T) cm². s-1 at about 2 atomic% K, where R is the gas constant in calole-Iegreci and T is the absolute temperature. The results were in good agreement with those estimated from Garfinkel's data (Fig.6).

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Aluminium triisopropoxide is a well known associate substance, and exists in trimeric, or tetrameric associate in crystal, or in solution. These associates in solid state are very stable and do not dissociate into monomers up to 200°C. Even in a solution, they do not dissociate upon adding a solvent or upon heating them at a high temperature. Thermal analyses were performed by using DSC. DSC curves of the crystalline aluminium triisopropoxide (ATP) show two endothermic peaks; the first is sharp and the second is broad. The observed differences among the first peaks, which are due to different crystallization procedures, suggest the. existence of two kinds of polymorphisms. In comparison with the first, the second peaks, appeared in two kinds of crystals, are in good agreement with each other and the occurence of the second ones reveals the presence of the markedly high binding energy in the intra-associate in preference to the inter-associate. Thus, DSC measurements manifested some interesting conclusions concerning the polymorphism, the dissociation of the associates, and the change in enthalpy and entropy.

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It is well known in an atomic absorption spectrophotornetry that phosphate or fluoride ion interferes with the determination of Ca or Fe and the interference is eliminated by the addition of such organic substance as EDTA. This report deals with the investigation on the elimination of the interference by dispersing the carbon black, (Mipubishi # 600, 14 nm) in terms of ultrasonic irradiation in the sample solution. EDTA or organic solvent was less effective than carbon black for the elimination of the anion interference at a high concentration. In addition, the burner head was contaminated with EDTA. Optimum concentration range of carbon black was 0.01.0.05 wiv%. The influence of other absorptive metals on carbon black, or the paticular change in blank test was not observed. Sample flow rate and background absorption were scarcely changed by the addition of carbon black and relative standard deviation of measurements was 0.10, --90.56%.

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The reaction of fi-(monosubstituted amino) a, 8-unsaturated ketones (enamino ketones) and ethyl /3- (monosubstituted amino) crotonates (enamino esters) [ 1 ](substituent: Ph, Me, H) with acetic anhydride or acetyl chloride and o-nitrobenzenesulfenyl chloride [ 6 ] was investigated, and the configurations of the products were established. The acetylation of primary and secondary enamino ketones and enamino esters gave N-acetylated [ 3 ] and/or C-acetylated products [ 2 ], while [ 1 ] reacted with 16 J to give exclusively C-(o-nitrophenylthio) subjtutes [ 4 ]. From the IR and NMR spectral data, it was confirmed that a few C-acetylated enamino ketones and enamino esters existed entirely in the intramolecular hydrogen bonded a-acetyl and a-ethoxycarbonyl enamino ketone form, respectively. Moreover, the effect of N-acetyl, a-acetyl and a-ethoxycarbonyl group on the delocalization of x-electrons in the hydrogen bonded chelate ring was discussed.

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Various binary mixtures consisting of a base and magnesium chloride promote the carboxylation of various kinds of active methylene compounds with carbon dioxide. Monocarboxylic acid is obtained as a only product in excellent yield. The reactions are promoted by such a strong tertiary amine as triethylamine or triethylenediamine, but not by such a weak tertiary amine as pyridine or N, N-dimethylaniline. Primary or secondary amines are not effective. Among the chlorides of uni-, bi-, and tri-valent metals, magnesium chloride is the most effective substance to promote the carboxylation of indene or acetophenone.

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N, N' -Disubstituted sulfuric diamides were obtained in good yield by the reaction of. N monosubstituted amidosulfate with phosphoryl chloride and pyridine under refluxing in 1, 2- dichloroethane. In addition to N, N'-disubstituted sulfuric diamides, N, N-bis(monosubstituted sulfarnoyl) alkylamine were obtained as a by-product under severe reaction conditions. On the other hand, sulfuric diamide was not obtained from N, N-disubstituted amidosulfate under similar reaction comditions. The formation of N, N'-disubstituted sulfuric diamides would be explained as equation ( 6 ).

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Mass-transfer effects on sulfonation of benzene or toluene with sulfuric acid and on the ratio of toluenesulfonic acid isomers were studied. In the homogeneous system, the reaction rates were measured by ultraviolet spectrophoto meter at different concentrations of sulfuric acid. The reaction rates were of the first order with respect to the concentration of benzene or toluene and the rate constants were expressed by exponential functions of the concentration of sulfuric acid. In the heterogeneous system, the reaction rates were measured by changing interfacial area, volume, or acidity of sulfuric acid phase. It was found that the reactions took place in the laminar film of sulfuric acid phase, which would be probable in view of the film theory, and that the diffusion rates of organic matter were lower than those of the chemical reaction, which would be probable in view of the reaction rate concept. The ratio of toluenesulfonic acid isomers f ormed in the heterogeneous system was in good agreement with that of them formed in the homogeneous system. This result can well be explained in terms of the mechanism that the diffusion and the chemical reaction took place simultaneously in the laminar film of sulfuric acid phase and that the reaction rates in the heterogeneous system were the same as those in the homogeneous one.

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Debromination of meso-Stilbene Dibromide by 2-Tetrahydrofuryl Hydroperoxide Kuniaki Iron Faculty of Science, Kwansei Gakuin University; Nishinomiya-shi 662 Japan Present Address: Department of Chemistry, Faculty of Science, Kobe University; Rokkodai, Nada, Kobe-shi 657 Japan Debromination of meso- and dl-stilbene dibromides by 2-tetrahydrofuryl hydroperoxide(THF HPO) in THF and its reaction courses were studied. When a solution of meso-stilbene dibromide in the ethereal solvent (THF, 2, 5-dimethyltetrahydrofuran, dioxane) was heated in the presence of air, the dibromide lost two bromine atoms to yield trans-stilbene. But no debromination was observed when their ethereal hydroperoxide(HP0) was thoroughly removed from the solution or when the radical inhibitor was added. Therefore, this debromination was considered to proceed by a radical chain reaction, which was initiated by the decomposition of their HPO. The reaction of 2-tetrahydrofuryloxyl radical, generated in THF by a redox pair, THF HP0 and iron(II) ion, at 0"---5°C, with vic-dihalides was carried out to give olefin, hydrogen halide, 3-halopropyl formate and the decomposition products of the HPO. On the basis ofquantitative analysesof the reactionproducts, it became obvious that the 2-tetrahydrofuryloxyl radical directly abstracted a halogen atom of the dihalide before the 8-scission to 3-f ormyloxylpropyl radical occured. The reactivity of dihalides to the oxyl radical decreased in the order, dl-stilbene dibromide, ---meso-stilbene dibromidestyrene dibromidetrans-1, 2- dibromocyclohexanemeso-stilbene dichloride. This order seems to depend upon the resonace stability of the radical produced by dehalogenation.

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A novel procedure for a preparation of 5-benzyl-3-furylmethanol [. / c] which is a useful intermediate for an insecticidal ester (pyrethroid) is proposed (Fig.1). An important starting material, methyl 3-methyl-2-furoate 4 was prepared from acetoacetaldehyde dimethyl acetal 2 and methyl chloroacetate C 3 under mild conditions. Bromination of 4 with N-bromosuccinimde (NBS) in the presence of a radical initiator (e. g. a'-azobisisobutyronitrile and white light) gave methyl 3-bromomethyl-2-furoate 5 . The brominated compound L5 was treated with sodium acetate in glacial acetic acid to give methyl 3-acetoxymethy1-2-furcate C 6 3, which was then chloromethylated to give methyl 3- acetoxymethy1-5-chloromethy1-2-furoate b. The key step in the present procedure is this chloromethylation of 2, 3-disubstituted furans.5-Chloromethylated furan b was treated with benzene to give methyl 3-acetoxymethyl-5-benzyl-2-furoate [10 la] which was hydrolyzed to give 5-benzy1-3-hydroxymethy1-2-furoic acid Cu1 c. An aqueous suspension of the furoic acid (11 c) in the presence of a small amount of potassium carbonate was decarboxylated at 190-200°C in an appropriate autoclave to afford 5-benzyl-3-furylmethanol Cl c in an excellent yield. The procedure described above may be one of the most convenient and of industrial use for synthesis of [1 c].

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Two polymeric dyes were prepared by homopolymerization of 4-E (m-methacrylamidopheny1)- azo-3-methyl-1-pheny1-2-pyrazolin-5-one ( I -M) and of 2-[ (m-methacrylamidophenyl) azo]acetoacetanilide -M to improve light fastness of azo series polymeric dyes. The GPC analyses and VP() molecular weight determination have proved that both the polymeric dyes have a broad distribution of molecular weight and that the average degree of polymerization ranges between 14 and 28, depending on the initiator concentration. Visible and infrared absorption spectra show that the polymeric as well as monomeric dyes are present as a hydrazone form but that the polymeric dyes are hypsochromic compared to the corresponding monomeric dyes. The comparison of light fastness of the polymeric and monomeric dyes have been made in poly (methyl methacrylate) cast film. No appreciable difference in light fastness between the polymeric and the corresponding monomeric dyes is observed (see Fig.1). Light fastness of the polymeric dye derived from I -M is considerable better than that of C. I. Pigment Yellow 1 used as a control, but that of a polymeric dye derived from II--M is very poor. Bleeding resistance of the polymeric dyes is excellent.

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The kinetics of the dyeing of formalized( I ) and acid-treated. formalized(II) -PVA fibers with direct dye have been studied at 80 and 90°C. Each dyeing was made in an infinite bath with 3 x10-5 molg of Congo Red and with 0.1 moll/ of sodium chloride. The apparent diffusion coefficient (D) and the apparent rate constant of dyeing (K) decreased with an increase in the degree of formalization of the fibers. D and K for If were fairly greater than those of I. The amount of dye adsorbed for II at equilibrium was markedly larger than that of I. It is suggested that the kinetics of the dyeing of PVA fiber with direct dye are appreciably affected by the cross-linking formed in the formalization reaction of the polymer.

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The effect of the quaternary salt catalysts on the displacement reaction of benzyl halides Ci a-1 g in aqueous cyanide solutions has been examined. Whereas hydrolysis to the corresponding benzyl alcohol takes place under conventional conditions, benzyl cyanides C2 g are obtained as a sole product in the presence of a catalytic amount of certain quaternary salts. Ammong the catalysts tetrabutylammonium bromide has given excellent results. The analysis of kinetic data in terms of a liquid-liquid heterogeneous reaction model has revealed that the reaction in the organic phase is rate-determined and that the rates of cyanide replacement show a first order dependence on the concentration of 1 a and catalyst. On the basis of apparent rate constants, the relations between catalyst structure and catalytic effects have been discussed. The efficiencies of catalyst have been evaluated quantitatively.

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An N-methylacridinium^-7, 7, 8, 8-tetracyanoquinodimethane complex salt (MAQ2) was dispersed into polymers. The effect of polymers on the properties of the polymer-MAW composites was studied. When the polymers having electron donor groups were used, uniform composites were obtained, and they showed high conductivities. The stronger was the electron donor groups in the polymer, the less the stability and conductivity of the composites became. When polycarbonates were used, the phase separation of the needle crystals of MAQ, ' was observed, and the values of resistivity of these composites were high in films. The stability of these systems was not lower than that of MAQ2'. It was considered that charge-transfer interaction existed among the electron donor polymers and MAQ2' in the uniform composites, but no interaction existed among the separated composites. The interactions among the polymers and MAQ, ' which depend on the structures of the polymers, affected the properties of the composites.

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Viscosity of PVC plastisol was investigated at 30-0.1°C by the use of an E type rotary viscometer. This PVC plastisol gives high viscosity only in the copresence of 2-dibutylamino1, 3, 5-triazine-2, 4-dithiol (DB) metal salts and polyethers (12.10CH8-ECH₂O-CH₂-KCH₂OR2). Polyethers which give high viscosity to a PVC plastisol have both such alkoxyl (OR) as OCH₃, 008148, OC, H and OH for two end groups. The viscosity of a PVC plastisol increases with increasing ether chain number of polyethers. Polyethers with two OH or two OCHE end groups scarcely increase the viscosity of a PVC plastisol. The viscosity of a PVC plastisol, also depends on the kind of metal in DB-metal salts and changes in the order MgCaBaNa, which agrees with the increasing order of electron negativity of the metals. On the basis of the above results and of the electronmicroscopic observation, the high viscosity behavior of a PVC plastisol was explained in terms of the speculation that crowds of ether groups, absorbed on the surface layer of PVC particles, coodnate to DB-metal salts and, consequently, PVC particles are combined with one another by an electrostatic force.

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To study the diffusion of ions in agar-agar gel, experiments were carried out for onedimensional diffusion of ions into agar-agar gel containing electrolyte or not. Concentration distribution of ions in agar-agar gel was measured at 25°C and the relation between the position of the precipitate and the time of its appearance were elucidated. The diffusion constants of K2CrO₄ and CuSO₄ in the gel of various agar-agar concentrations not containing electrolyte were determined on the basis of the concentration distribution of CrO^2-2- and Cu". In the K2CrO^2--CuSO₄ agar-agar gel system, when 1. 2CrO₄ diffuses into the gel containing CuSO₄, the concentration of sol particle, as a reaction product in the gel, is about one order of magnitudes greater than that in water. Accordingly, the outer electrolyte diffuses into the innner region across the precipitation front. The concentration distribution obtained was cornpared with the calculated one obtained by a model based on the unsteady state diffusion accompanied by an instantaneous reaction between two electrolytes. As a result, for the concentration distribution of CrO^2-2- and Cu" in the region of the continuous precipitation, the experimental values were in good agreement with the theoretical ones. Furthermore, it was found that in the case of the formation of precipitates with rhythmical type, the advancing speed of the front could be approximately estimated by this model.

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The electrochemical oxidation of iron cyanide complex ions hexacyanoferrate(II) and (Ill ions) in aqueous solutions was carried out under the irradiation of ultraviolet light. Hexacyanoferrate ( I1) and (111) ions in alkaline solution were converted into aquapentacyanoferrate10 ions under the ultraviolet irradiation. Upon further irradiation, they released cyanide ions and iron (Ill) hydroxide precipitated. The irradiation experiments were carried out by using three types of mercury lamp. The release rate of cyanide ions was in the following order: low super lowhigh pressure lamps and accelerated with increasing pH of the solution. Since released cyanide ions were easily oxidized electrochemically, iron cyanide complex ions could be decomposed by the combined use of ultraviolet irradiation and electrochemical oxidation.

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Polymerization of cyclic dimer of 6-hexanelactam catalyzed by sodium hydroxide in the presence of polyhexanamide was studied. The polymerization proceeded according to the firstorder kinetics and the rate constant was expressed by the sum of the catalytic term (k_cocm) and the non-catalytic term (k_cooNa) On the basis of the experimental results, k_comi and k-cooN. at 310°C were calculated, respectively, as7follows k-cooH =0.31 x 10-2(//hr)/ (-NH₂ meq/kg), k_cooN. ---=0.10 x 10-2(//hr)/(-NH₂ meq/kg).

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Polychlorinated biphenyl (PCB) was effectively decomposed by heating it in a molten mixture (mp: ca.110°C) of A1Cl3 (60 mol%), NaCl (20 mol%), and KCl (20 mol%). As shown in Table 2, 53.9g of PCB, consisting mainly of trichlorobiphenyl, was decomposed giving 23.9g of carbonaceous matter by treating it with the above mixture for 10 hours at 400°C under airbubbling. The amount (12g) of unchanged PCB, recovered as benzene soluble matter, diminished to a few grams after twice treatment. Another kind of PCB, consisting mainly of pentachlorobiphenyl, reacted rarely as above, while it decomposed in the presence of aluminium powder yielding an insoluble and infusible carbon-like matter.

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