Schiff bases such as 4-substituted N, N'-bis(1-acetonylethylidene)-1, 3-[1], 3-substituted N, N'-bis(1-acetonylethylidene)-1, 4-benzenediamines [2], and 4-substituted N-(1-acetonylethylidene)-1, 3-benzenediamine[3] (substituent; Cl, H, CH₃, OCH₃ or OH) were synthesized by the condensation of acetylacetone with corresponding benzenediamines in ethanol. The predominant structure among the enol imine-keto enamine tautomeric isomers of these Schiff bases was estimated on the basis of IR and NMR spectra, and the absorption bands in ultraviolet region were assigned. The presence of vm, and vc, c, absorption bands at 3200-3000 cm^-1 and 1620-1600 cm^-1 respectively, and of CH and NH protons signals at 4.9-5.3 ppm and 11.9-43.2 ppm, again respectively, indicated predominance of keto enamine form which have the chelate ring in terms of intramolecular hydrogen bond. It was found from IR and NMR spectra of [ 1] and [2] that the methyl radical bonding to nitrogen atom side and the hydrogen bonded imino radical of chelate ring adjacent to the substituent of 3- or 4-position of aromatic ring are not equivalent, when compared them with those of the chelate ring of 1-position. The absorption bands of 44-42 x 10³cm^-1 and 32-28 x 10³cm^-1 observed in ultraviblet region were

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Methanation of CO and CO₂ over Ni catalysts supported on various oxides was investigated by means of a pulse, a continuous flow, and temperature-programmed desorption techniques. With CO-methanation the apparent reaction rates were roughly proportional to the Ni surface area of the catalyst. In contrast, CO₂-methanation proceeded considerably over the Ni/MgO catalyst in spite of its small Ni surface area. Ni on silica-alumina having a larger Ni surfase area was less active in CO₂-methanation. The specific activity was not so sensitive to a support material in CO-methanation. The results of a temperature-programmed desorption of CO showed that CO was adsorbed strongly at the temperature range of CO-methanation higher than about 130°C. On the other hand, CO₂ was adsorbed weakly except on the Ni/MgO catalyst, and the adsorbed CO, readily desorbed below the temperature range of CO₂-methanation. The high activity of the Ni/MgO catalyst for CO₂-methanation might be associated with its high activity of CO₂ adsorption. The reaction rate of CO-methanation was found to be first order with respect to the H₂ partial pressure, and to be zero order with respect to the CO partial pressure. For CO₂-methanation the reaction order varied between 0.3 and O.6 with respect to the CO, partial pressure and was near zero with the H₂ partial pressure.

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By using a pulse technique, CO and CO, methanations were studied on a Ni/SiO₂ catalyst at around 200°C. Gas chromatogram of the products obtained from CO and CO, methanations showed the pronounced tailing of the CH4 peak, as shown in Fig.2. In methanation from the mixture of CO and H₂ or CO, and H₂ using He as a carrier gas, the tailing of the CH4 peak was not observed, and the amount of the product was less than that formed in H₂ carrier gas by a factor of about 100. These results indicated that the stable adsorbed intermediate, (X)0, d, formed on the catalyst from CO or CO, was methanated slowly. From the kinetic studies of these tailings, the rate constants of the surface reaction and the activation energies in CO and CO, methanations were determined. In both reactions the rate constants of the surface reactions were in good agreement with each other and the activation energies were 19 kcal/mol, as shown in Fig.5, indicating that CO, methanation proceeded through the same intermediate as that in CO methanation. By adding the results of CO disproportionation, it seemed more probable that (X)0, d was M-CHOH rather than M-C or M-CO.

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N-Methylation of aniline with methanol over MgO catalyst was carried out by using a continuous flow reactor at an atmospheric pressure. The reaction proceeded both acidic and basic positions as active sites, and N-methylaniline was selectively produced. The optimum conditions for this reaction were as follows: reaction temperature was 480°C and contact time was 6.7g-cat·hr·o1-1. The reaction order was of O.5 with respect to aniline, and of O.4 with respect to methanol. The observed activation energy was 16.2 kcal/mol.
The effects of substituents on this reaction were discussed on the basis of the Hammett law: the reaction constant p was -1.73, indicating that this reaction is an electrophilic one. The reaction constant and the rate equation for substituted anilines suggest that the rate-determining step of this reaction is an attack of methylation on aniline.
The order of the catalytic activity of MgO containing an additional substance was found to change in the following order: MgO(containing 2 wt% S0, 2)Mg0(prepared from Mg(OH)2)=MgO (containing 2 wt% PO₄8) MgO (prepared from 4 MgCO₃Mg(OH), 5H₂O). The influence of calcination temperature on the catalytic activity was less for MgO(containing 2wt% SO₄^2-) than for other MgO catalysts.

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The structure of alumina-supported palladium catalysts has been studied. The catalysts were prepared by an impregnation method and were calcined under different conditions (Table 1). Amount of uptake of both CO and O₂ on the catalysts was determined by a pulse technique. The degree of dispersion of palladium, D, ratio of number of Pd atom on the surface to total number of Pd atom, was evaluated from the amount of CO uptake. The difference between the amount of 0, uptake and a half of the amount of hydrogen required to form the monolayer adsorption on surface palladium, %IT, was regarded to be the amount of O₂ consumed by hr drogen atom diffused from alumina to palladium.471 is approximately proportional to D and the amount of palladium on the surface being in contact with alumina surface.
Two types of palladium re-dispersion which bring about an increase in surface area of palladium were observed in the Pd-Al2O^2- (Cl) catalysts containing chloride ion (Figs.3, 4 and 5). The results were explained as follows: In the presence of sufficient amount of chloride ion, fine palladium metal is formed via an intermediate which was considered to be a certain complex between palladium chloride and surface alumina. On the other hand, in the absence of chloride ion, rough palladium metal with many holes is formed via palladium oxide crystallite.
The hydrogenation of benzene was carried out with both simply calcined catalysts and redispersed catalysts, by using the pulse technique. It was found that the catalytic activity depends on the structure (Figs.6 and 7). The activity per atom of surface palladium is dependent on D whose values being 0.2-1.0 (Fig.8). After further discussion, it was concluded that when D is less than 0.73 this dependence was considered to be the migration of hydrogen, spilt over alumina.

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Cooperative incorporation of dinitrogen and sodium (or cesium) takes place on metallic ruthenium, as observed with potassium. Although the rate of dinitrogen incorporation decreases in the order of Cs K Na as shown in Fig 1., the relative amount of dinitrogen aginst sodium, (or cesium) incorporated is close to unity, indicating that the compounds, (MN₂ Ru) n analo- gous to (KN₂Ru), as suggested for K-Ru system are also formed in the Na-Ru or Cs-Ru system. The above uptake sequence of alkali metals are in accord with the activity sequence of ruthenium catalysts promoted by alkali metals in the isotopic equilibration of dinitrogen as shown in Fig 2.
The cooperative incorporation of dinitrogen and potassium was further examined for other Mil th group metals. The extent of dinitrogen uptake on those metals in the presence of potassium (under conditions of 350°C, 300 Torr N₂) was found to be much less than that on ruthenium, while the uptakes on iron family metals are generally larger than those on cobalt family metals. Since the potassium uptake increases linearly with increase in the dinitrogen uptake with an inclination of unity in mole basis as shown in Fig 3, the analogous ternary compounds of potassium-dinitrogen-transition metals are suggested. In addition to (KN₂ Ru) n the iron and osmium compounds, in particular, were found to give hydrazine upon hydrolysis of these compounds.

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The mechanism of H₂0 activation over Rh catalysts supported on various metal oxides (Al2O^2-, SiO^2-, Cr208, UO₂, VO^2-, MoO^2-, and WO^2-) was studied by the pulse reaction using CO and H₂0 as reactants, and was discussed in relation to m-xyleneteam reaction. Rh/metal oxide catalysts were generally classified into two groups on the basis of the mechanism of H₂0 activation. First, in the activation of H₂0 over Type I catalysts (Rh/Al2O^2-, Rh/SiO^2-, and Rh/Cr2O^2-) surface OH groups are formed (Eq. (4)). Second, in the activation of H₂0 over Type II catalysts (Rh/UO₂, Rh/VO^2-, Rh/MoO^2-, and Rh/WO^2-) the cleavage of H₂0 molecule into gaseous H₂ and surface oxygen atom occurs (Eq. (7)). The resulting surface OH groups (Type I catalyst) and resulting surface oxygen atom (Type 11 catalyst) were both active for CO oxidation (Eqs. (2) and (6)). The order of the activities for CO oxidation of the Rh/metal oxide catalysts was well correlated to that of the steam-dealkylating activities for m-xylene, which were measured by a flow reaction method.

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The inhibition effect of 6-substituted 1, 3, 5-triazine-2, 4-dithiol monosodium salts (RTD, 6- substituted groups; -N(C₄H₉) =DB, -NHC₃H₅= AN, -SH, TT) on the corrosion of copper al loys has been investigated in the ASTM aqueous solution without mechanical agitation at 50+ 1°C for 20 days. The inhibition of RTD was affected by the kind and amount of secondary metal component such as Zn, Al, Sn and Ni in copper alloys. The corrosion of copper alloys was completely inhibited in the presence in DB and AN with concentration more than 10^-4 mol//. The effective concentration of AN for the inhibition of the alloys corrosion remained unchanged regardless of the kind of copper alloys, while the effective concentration were affected by the kind. Especially, TT was effective only for the inhibition of Cu-Zn alloy and Cu-Ni alloy. In a 1% aqueous solution, AN gave a high inhibition effect on the corrosion of Cu-Zn alloys, a Cu-Sn alloy and a Cu-Ni alloy. Polarization measurements showed that RTD inhibited both anodic and cathodic reactions on the surface of copper alloys. However, RTD seems mainly to act as a stranger anodic inhibitor from inhibition view points, The reactions of RTD with the surface elements of capper alloys are also discussed with Polarization resistance measurements of copper alloys in an aqueous RTD solution.

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The phase equilibrium relationship of the system LiVO₃NiO in the three component system Li2O-Ni0-17205 was investigated by means of high and normal temperature X-ray diffraction techniques, thermogravimetric analysis, and differential thermal analysis. The phase diagram of the system LiVO₃NiO was constructed in the temperature range between 500° and 1550°C. The successive processes in air from a mixture of Li2C08, NiO, and 17205 to a spinel type compound LiNiVO₄ proceeded through the formation of both LiNi(VO₃)3 and LiV0₃. The lattice constant of LiNiVO₄ at 1000°C worked out at 8.220±0.001 A, whereas it was 8.217 A at 700°C. About the change in the lattice constant it appeared that the cation arrangement in LiNiVO₄ is NirVt_Olv (LiNixs)M0, (1 x 0.15), so that the change may be caused by an increase in the concentration of Ni²⁺ ion in the tetrahedral sites. However, to occupancy of Li+ in the four coordination positions and oxygen deficiency at high temperature are also Possible, so that these may leave problems to be solved in future. For LiNiVO₄ the electric conductivities over the temperature range from 250° to 1050°C and the thermoelectromotive forces at about 900°C were measured. Activation energies 1.48 eV above 810°C and 0.557 eV below 810°C came out from the electric conductivity measurements. Oxygen partial pressure depen- dence of the electric conductivity of LiNiVO₄ was examined over the range 6 X 10-5 to 1 atm of Poe No correlation was gained in the PO₂ ranges 6 x 10-5 to 4 X 10-3 and lx 10-' to 1 atm, but the electric conductivity was in proportion to PO₂^-0.23';."over PO₂ 4 x 10^-3' to 1 x 10^-1' atm.

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Emerald crystals have been formed in two binary fluxes of Li20-MoO^2- and Li2O-V205 using the slow cooling method and the temperature gradient method under various conditions. In the flux of Li20-MoO^2- carried out in the range of 2-5 of molar ratios (MoO^2-/Li20), emerald was crystallized in the temperature range from 750 to 950°C, and the suitable crystallization conditions were found to be the molar ratio of 3-4 and the temperature about 900°C. In the flux of Li20-1/205 carried out in the range of 1.7-5 of molar ratios (V205/Li20), emerald was crystallized in the temperature range from 900 to 1150°C. The suitable crystals were obtained at the molar ratio of 3 and the temperature range of 1000-1100°C. The crystallization temperature rised with an increase in the molar ratio of the both fluxes. The emeralds grown in two binary fluxes were transparent green, having the density of 2.68, the refractive index of 1.56, and the two distinct bands in the visible spectrum at 430 and 600nm. The emerald grown in Li20-V205 flux was more bluish green than that grown in Li2O-MoO^2- flux. The size of the spontaneously nucleated emerald grown in the former flux was larger than the latter, when crystallized by the slow colling method. As for the solubility of beryl in the two fluxes, Li20-VP5 flux was superior to LiO-MoO, flux whose small solubility of SiO₂ caused an experimental problem to the temperature gradient method. The suitability of the two fluxes for the crystal growth of emerald by the flux method was discussed from the view point of various properties of above-mentioned two fluxes.

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The extent of the interference caused by co-existence of a sulfate ion on the flame atomic absorption spectrophotomety of calcium, and removal of the interference by addition of carbon powder such as carbon black and active carbon were studied. The addition of carbon black was found to be very effective. The optimum amount of carbon black to be added was about 0.08% to the sample volume. Absorbance of calcium solution accompanied with a sulfate ion was increased 50% by the addition of carbon black, while calcium solution without a sulfate ion showed 1.2 times greater absorbance by the addition of carbon black. As both absorbance for the samples containing carbon black were agreed precisely, the addition of carbon black was recognized to remove the interference of a sulfate ion completely. The addition of organic solvents were found to be incapable of removing the sulfate ion interference.

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A packing method of strongly, acidic cation exchange resin which is 5-6 am in particle dia, meter and 12% cross-linked divinylbenzenesulfonic acid was studied in order to obtain a high and stable column efficiency for the separation of amino acids. It was found that the column packed at higher pressure yielded a higher resolution when the dynamic slurry packing method *as emplo3ied. The resin was allowed to shrink by treating with a solution containing a high concentration of alkali: metal salt solution or a mixed water-ethanol solution prior to the high pressure packing. Height equivalent to a theoretical plate of 0.018mm for glycine was obtained with a column packed with a slurry of the resin involving 2 molg LiCl solution at 200 kg/cm' 'for 2 hours.

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1, 2, 3, 4-Tetrachlorobutanes (TCB) were dehydrochlorinated by sodium hydroxide in aqueous methanol to give 2, 3-dichloro-1, 3-butadiene (2, 3-DCB-1, 3) and 1, 2-dichloro-1, 3-butadiene. Dehydrochlorination of meso-TCB gave cis-1, 2, 4-trichloro-2-butene together with the substi- tution products, cis-1, 2-dichloro-4-methoxy- and cis-1, 4-dimethoxy-2-chloro-2-butenes. On the other hand, dl-TCB was converted into trans-1, 2, 4-trichloro-, trans-1, 2-dichloro-4-methoxy-, and trans-1, 4-dimethoxy-2-chloro-2-butenes. meso-TCB was converted into 2, 3-DCB-1, 3 in a good yield, whereas a fairly large amount of the methoxy compounds was obtained from dl-TCB. Since 2, 3-elimination took place by the trans-elimination of hydrogen chloride from dl-TCB as a starting material, 2-alkenes were favorably formed.1, 2-Elimination dominated in meso-TCB because of steric requirement and, as a result, 2, 3-DCB-1, 3 was obtained in a good yield. Further results obtained are summarized as follows. (1) The yield of 2, 3-DCB-1, 3 depended on the ratio of methanol to water, and showed a maximum in the range 75-85 vol%. (2) As the concentration of sodium hydroxide increased, the yield of 2, 3-DCB-1, 3 from meso-TCB decreased, and that from dl-TCB increased. (3) With the increasing reaction temperature, the selectivity for the formation of 2, 3- DCB-1, 3 from meso-TCB decreased and that from dl-TCB increased.

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Phenylacetylenes E 1 reacted with aliphatic azomethines C 2 J in the presence of a catalytic amount of zinc chloride, yielding 3-phenyl-2-propynylatnines C 3D. The reaction of p-nitrophenylacetylene with N-isobutylidene-t-butylamine gave, in addition to propynylamine 13 k, trans-2, 2-dimethy1-4- (p-nitrophenyl) -3-butenal C 6 J after treatment with acid. Phenylacetylenes C 1 reacted with N-benzylideneanilines C 7 J under catalytic influence of zinc ( chloride to give quinoline derivatives C10). Analogously, 2, 4-diphenylbenzo[h]quinoline C.12 was obtained from phenylacetylene and N-benzylidene-1-naphthylamine. The present method offers a facile synthetic route to a variety of 2, 4-diphenylquinoline derivatives.

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A novel synthesis of alkylpyridines from some lower olefins and ammonia was studied. In a series of reactions of ethylene with ammonia in the presence of palladium(j) chloride, 27methylpyridine and 5-ethyl-2-methylpridine were predominantly obtained in high yield. when copper(11) chloride as a redox reagent was added to the above system, palladium(jI) chloride was found to function as a catalyst, and both the conversion of ethylene and the selectivity of alkylpyridines were increased remarkably. The optimum conditions for production of alkylpyridines were as follows; the reaction temperature was 200°C and the molar ratios of PdCl2/ C_2CI-I4, CuCl2/C_2CH4, and NH₃/CuCl2 were O.01, 1-1.5, and 5, respectively. Under these conditions, the conversion of ethylene was nearly 65%, and the selectivities for 2-methylpyridine and 5-ethyl-2-methylpyridine were 7, -12% and abuot 48%, respectively. It is assumed that the reaction proceeds via acetaldehyde formed by the catalytic reaction of tetraammine palladium and-copper complex ions with ethylene.

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The Pariser-Parr-Pople MO mthod including the variable β approximation was applied to the calculation of electronic absorption spectra of azobenzene derivatives. The best values of necessary parameters for the azo group were determined by using the orthogonal array table L9 in the experimental design method.
On the basis of the results calculated by use of these optimum parameter values, the substituent effects on λ_max a of azobenzene derivatives. were discussed. An examination of hydrogen bond and steric effects on λ_max appears to suggest that the direction of the shift of Am. x due to the hydrogen bonding. at the /β-nitrogen atom of the azo group depends on the electron-withdrawing power of sUbstituents, and that the observed bathochromic effect of the 2-methyl group on the λ_max of 4-dimethylaminoazobenzene is attributed to the steric hindrance between the azo and the 2-methyl group.

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Catalytic reduction (5% platinum or 5% palladium placed on carbon and under 1 atm of H₂) of o-nitroanisole ID with hydrogen was carried out in sulfuric acid-methanol solution at a room temperature. The reaction products were o-anisidine [2], 2, 4-dimethoxyaniline [3], and 2, 6-dimethoxyaniline[4]. The products [3] and [4] were considered to form in terms of the Bamberger-type rearrangement of o-methoxyphenylhydroxylamine, formed in the course of catalytic reduction of to [1]to[2]. The yield of amines ([2], [3], [4]) was significantly dependent upon the amount of sulfuric acid. Pt-C catalyst is more effective than Pd-C to obtain significant amount of [3] and [4] When catalytic reduction of [ 1] (4.0 g) over Pt-C (120 mg) was carried out in 40 ml of methanol, the maximum yield of [4] was achieved when 20.0 g of sulfuric acid was added (the yield of C[2], [3], or [4] being 56%, 12%, or 27%, respectively) and that of [3] was achieved when 40.0 g of sulfuric acid was added (the yield of [2], [3]or[4] being 33%, 26% or 2%, respectively). It was also found that addition of dimethyl sulfoxide, a catalyst poison, enhances significantly the yield of rearrangement products: for example, while the yield of [2], [3], or [4]being 81%, 18%, or 1%, respectively, in the case of 2.8 g of sulfuric acid and in the absence of dimethyl sulfoxide, the yeild of [2], [3] or [4] being 55%, 28%, 9%, respectively, in the presence of dimethyl sulfoxide (0.05 m/).

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Methronole, cyclic dimers of (1-propenyl)benzene, was shown by their NMR spectra to be a mixture of almost equal amounts of 1, 2-cis-2, 3-trans (a-racemate) and 1, 2-trans-2, 3-trans (r-racemate) isomers of 1-ethyl-2-methyl-3-phenylindans. Various kinds of reaction conditions were examined to obtain the dimers (Table 2), and it was found that the ratio of the formation of r-racemate to a-isomer increased as reaction temperatures were raised.

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The polymerization of vinyl monomer initiated by the system of hydrophilic macromolecule, Cu TO ion, and water was called"uncatalyzed polymerization"by the authors, because of an absence of conventional initiators. A revised initiation mechanism of this polymerization was expressed by Eq. (2). The invariance of the valency of Cu 10 ion during the polymerization was confirmed by ESR spectra. The formation of a complex between Cu(11) ion and macromolecule was ascertained by UV spectrum and electro-conductivity methods. A HMO calculation supported the mechanism expressed by Eq. (2). Kinetic behavior showed that the process of polymerization was as follows: (1) The hydrophilic macromolecules form hydrophobic area (HA) which is the agglomerate of the macromolecules giving at the same time the reaction field favorable to polymerization; (2) In this HA, vinyl monomer is incorporated; (3) Then, in it, the radical polymerization proceeds. By scanning with electron microscopic method, the formation of HA of chondroitinsulfate and poly(vinylphosphonic acid) in a water phase became apparent. It has previously been reported by the authors that Michaelis-Menten-Lineweaver-Burk's equation could well be applied to the uncatalyzed polymerization, and the reaction order with respect to macromolecule was O.5 or 1. O. In order to explain these results, the kinetics of polymerization was considered. Also this paper deals with a summarized conculusion obtained from the studies on the uncatalyzed polymerization.

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As a study on the preparation of well-defined polymers, the grafting reaction of living polystyrene with methyl vinyl ketone-styrene copolymer (P(MVK-S)), acrylaldehyde-styrene copolymer, methyl acrylate-styrene copolymer, or poly (methyl acrylate) was carried out under various reaction conditions, and the grafting efficiencies of the backbones were evaluated by means of gel permeation chromatograph (GPC). The solvent effect on the degree of grafting was noticeable in the reaction of polystyryllithium with P(MVK-S); the extent of grafting of living ends was 46% or 72% when tetrahydrofuran or benzene was used as a solvent, respectively. Although the influence of reaction temperature on the degree of grafting was not significant, it was high at a low reaction temperature. When Li+ was used as a counterion of a polystyryl anion, the extent of grafting of living ends reached the higher value of 86%, but in the case of K+ it was 26% at most. This striking effect of counterions suggests that the strong coordination of Li+ to the oxygen atom of a carbonyl group makes the carbonyl carbon atom more electropositive and, consequently, makes the nucleophilic addition of a carbanion more esey. On the basis of the GPC measurements and the model reaction by use of 3-methyl-2-pentanone, a side reaction in this grafting reaction was confirmed to be ahydrogen abstraction due to polystyryl anions.

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The grafting reaction of p-formylstyrene tyrene copolymer (P(FS-S)) with living polystyrene was investigated. The extents of grafting of living ends and formyl groups were evaluated by both the GPC method and an"Me method"which was based on the increase in the number-average molecular weight of the polymer recovered after the grafting reaction. It was shown that living polystyrene was grafted onto P(FS-S) to a high extent of 70-80% in a polystyryllithium-benzene system. In a polystyrylpotassium-THF system, the extent of grafting of living ends was as high as 75% at a low mole ratio of living ends to carbonyl groups ([LE]/[C=0] = 0.207), but it decreased with increasing [LE]/[C=0] ratio and was 53% when its ratio was O.866. In case of the reaction of p-isopropylbenzaldehyde with a, a-dimethylbenzyl-K which is regarded as the model reaction, the carbonyl addition took place almost quantitatively. These facts suggest that the carbonyl addition of living polystyrene is susceptible to the steric hindrance by branches. GPC measurements of the recovered polymers gave evidence that the grafting reaction involves to a small extent the monomeric termination and the dimeric termination of living polystyrene and the cross-linking reaction of backbone polymer as side reactions.

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In order to clarify the thermal degradation mechanism of polyamides and the correlation of the mechanism and evolution of toxic gases (HCN, CO), thermal analyses and thermal degradation were carried out for Nylon 6, Nylon 6 cross-linked by disulfide chains, Nylon 6, 6, silk and wool under a He stream and in vacuum. The degradation products were characterized by GC, MS and IR.
The thermal degradation of the synthetic polyamides was initiated at 320-350° C and their thermal gravimetric analysis always showed one-step TG curves. The main products obtained from pyrolyses of Nylon 6 and Nylon 6 cross-linked by disulfide chains were e-caprolactam and CO₂, and the amount of e-caprolactam from Nylon 6 cross-linked by disulfide chains was larger than that from Nylon 6. e-Caprolactam was assumed to be produced by a radical mechanism. In case of Nylon 6, 6, the main products were CO₂, NH₃ and H₂O. However, HCN and CO were scarcely evolved in the pyrolyses of these synthetic polyamides.
In contract to the case of synthetic polyamide, the thermal degradation of silk and wool was initiated at 200-250° C, and yielded CO₂, H₂0 and NH₃ as the main products. In this case, the TG curves showed three-steps, and hence the cross-linked reaction was assumed to occur easily and to produce larger amounts of HCN and CO compared with synthetic polyamides.

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Preparation of activated carbon(AC) from 8 species of coal whose coking property and ratios (1.87.7) of fixed carbon (FC) to volatile matter(VM) being differ widely, was studied to find the most suitable process or conditions to obtain a large surface area Sg(m2(AC)/g(AC)) and a high yield Y(g(AC)/g(raw coal)). The value of Sp= YS. (m2(AC)/g(raw coal)) or Se= YS, /ce(m2(AC)/g(sum of FC and ash)) was used as a criterion, which was expected to attain a high value as possible.
The two-step activation process which was the combination of carbonization of coal to char with flowing air, HCl-air mixture gas, CO, (dry method), and/or conc. H₂SO₄(wet method), and activation of char with steam, as well as other process of direct activation of coal were tried and compared, changing such experimental conditions as carbonization atmosphere, carbonization temperature and time(4° Cimin, 300-400° C, mainly 3 hrs for dry method; 150° C, 1 hr for wet method), activation atmosphere(H₂O-N, , CO₂, 1120-0O^2-N2; mainly 10% H₂ON2), activation temperature, and time(700-1000° C, mainly 900° C; 0.5-7 hrs). Drying at 110° C for 1 hr in air was selected as the weight criterion of raw coal(-12/-1-24 mesh, average diameter 1.0 mm).
The main results obtained are as follows:
( 1 ) The coking property and the ratio of FC/VM of coal in the direct activation process and the carbonization methods in the two-step activation process, namely the physicochemical properties of coal and char, controlled the pore developing process(S, vs. Y; Sc vs. Yla) through the activation. The basic carbon structure of AC, found by X-ray diffraction analysis, had been determined by the structure of coal or char prior to activation.
( 2 ) To prepare AC of large S. in high yield, the direct activation and two-step activation by dry carbonization were excellent for raw coal whose FC/VM was below 3 or the content of FC+Ash was below 75%, and the two-step activation by wet carbonization was suitable for raw coal of high degree of coalification. The typical performance in this study was to prepare AC with S. =500-1000 m2/g, whose yield being 40, -70%, comparable to commercial ACs.
( 3 ) Steam(10% H₂0-N2) activation at relatively high temperature(900° C) for 0.5-, 2hrs was preferable to a low temperature and long-time operation. Pretreatment of char with an inactive gas(N2) at 900° C improved the yield of AC during activation, forming partially hard carbon in char.
( 4 ) Adsorption capactity(q) of prepared AC for 12, UO₂2+ and PO V' in liquid phase was independent of raw coal and preparation methods, and showed proportionality toward S. as follows: q (mg (12) 1g (AC) ) =1.20 S.(A), q(mg (U)1g (AC) ) =0.18 S. (B) or q (mg (PO₄8-) / g (AC) ) = 0.012 Se. (C).
( 5 ) Catalytic activity of prepared ACs for air oxidation of Fe"in sulfuric acid solution was comparable to that of commercial AC prepared from coconut shell. As reported previously. the ACs prepared from poly(vinyl chloride) and polycarbonate gave the same adsorption abili- ties as shown in Eqs. (A) and (B), but only half in Eq. (C), and no catalytic activity toward air oxidation of Fe'.

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Nitrogen monoxide NO was oxidized to nitrogen dioxide NO₂ with corona discharge in the presence of 02. Electrical factors were studied in the oxidation reaction. The following results were obtained:
( 1 ) Negative corona is most effective for the discharge oxidation of NO.
( 2 ) For a given applied power per unit gas volume W(Wh/m8), the amount of NO oxidation, q is independent of the residence time of the gas mixture, and proportional to W0.7-0.8.
( 3 ) At a constant power W the amount of NO oxidation increases with the decrease of the radius of the discharge pipe used R(mm).
( 4 ) The radius of discharge wire r(mm) has an optimum value rM, for the discharge reaction.
These results are summarized by
Where a and 8 are experimentally determined parameters; a=0.7-0.8, 80(rrm), O(rrm).

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The reaction of NO and 02 in gas mixtures of N2, 02 and NO was studied in corona discharge. The reaction mechanism was discussed in connection with 03 generated. Conclusions are as follows.
1) At given discharge power, the amount of NO oxidation is independent of NO concentration, but dependent on 02 concentration. The amount of NO oxidation is proportional to 02 concentration in negative corona, but nearly constant for the content of 02 above 5% in positive corona.
2) At 200 ppm NO-20% 02-N2 Balance, NO is oxidized to NO₂ in negative corona, and the amount of NO₂ determined reaches the miximum value at a supplied electric power of 40 Whims. When higher power is supplied, a very small amount of N20 is observed, and 0, begins to be observed.
3) These results showed that the main reaction takes place due to the oxidation of NO by 03, that is generated in corona discharge.

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Nitrogen monoxide NO was oxidized in corona discharge in the presence ofj O^2-. The effects of gas temperature and of the amount of 1120 and SO₂ added on the discharge reaction were studied. The effect of NI-I, added on NO decrease was also studied. The following results were obtained: ( 1 ) The amount of NO oxidation increases with the decrease of temperature, and is approximatedly given by exp(2800/T). Nitrogen oxide NO is generated at high temperature. ( 2 ) Water vapour H₂O increases the amount of NO oxidation and lowers the amount of NO generated. (3 ) For no addition of NH₃, NO oxidation is independent of the concentration of SO, contained. ( 4 ) In the case of the addition of NH₃, the amount, of the decrease of NO increase in. the presence of SO₂, and the increases is greater for higher concentration of SO₂ Jane' larger amount of NH₃ added. However, the addition of NH, is hardly effective over the equivalent to NO and SO₂.

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Activated carbons were prepared from residual carbons in tires pyrolyzed at 550°C for 30 minutes. The composition of rubber of the tires used in this study was SBR 60, BR 40, and carbon black 70 in weight respectively. Three species of carbon blacks, HAP, HS-HAF, and GPF, which had different structures and diameters were used. In order to elucidate the influence of different properties of rubber, NR 80-SBR 20/HAP 50 system was also investigated. The residual carbons were ground to the fine powders and granulated to particles in size of 3.5-12 mesh. A sulfite pulp waste liquor was used as a binder. The activation of the granulated carbons was carried out in a stream of CO, at 900°C by using the vertical activation reactor made of quartz glass tube, 40 mm I. D. and 400 mm length. The adsorbability for Methylene Blue, specific surface area, and pore size distribution of activated carbons were determined. It was observed that the activated carbons obtained in this study had a characteristic pore size distribution. All of the activated carbons had a narrow pore size distribution concentrated at around 300-320 A in radius in both cases of SBR-BR-HAF and SBR-BR-HSAF, 630 A in case of SBR-BR-GPF, and 250 A in case of NR-BR-HAF. It seemed that these characteristic pore size distributions depended on the type of rubber species, natural or synthetic rubber, and particle size of carbon blacks in the tires. On the other hand it may be considered that the pore size distribution measured in this study represents the empty spacing surrounded by the walls of the external surfaces of very fine carbon partjcles.

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A combined anion-exchange-spectrophotometric method has been developed for the determination of zirconium and uranium in silicate rocks. A rock sample weighing about 1 g is decomposed with a mixture of perchloric and hydrofloric acids and is taken up in hydrochloric acid. If any residue remains, it is absolutely necessary to open it up by sodium carbonate fusion and to combine with the main fraction. Traces of zirconium and uranium are then co-precipitated together with aluminum and iron(a) hydroxides, and adsorbed by anion exchange on a Amberlite CG 400 column from 0.1 moll/ sulfuric acid solution. The adsorbed zirconium and uranium are eluted consecutively with 4 mold hydrochloric acid and 1 mol/l perchloric acid. Zirconium and uranium in the respective effluents are subsequently determined photometrically with arsenazo III. Results on the determination of zirconium and uranium in standard rocks of the U. S. Geological Survey and the Geological Survey of Japan are quoted.

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The reactions of meso-1, 2, 3, 4-tetrachlorobutane (TCB) and 3, 4-dichloro-1-butene (3, 4-DCB1) with sodium hydroxide in aqueous alcohols were performed at 30°C in order to see the effects of the nature of alcohols upon the rates of the reactions. The consumption rate of TCB was found to decrease in the order: i-PrOH s-BuOH EtOH PrOH i-BuOH BuOH C51-1110H C8H130H Me0H. A similar reactivity order was observed in the case of 3, 4-DCB-1: i-PrOH PrOH Et0H s-BuOH i-BuOH BuOH C51-1110H C61-1180H Me0H. The trends may be explained in terms of the inductive and steric effects of alkyl groups on the nucleophilicity of alkoxide anions.

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The reaction of the benzyl Grignard reagent with alkyl chloroformates has been investigated. The reaction with methyl chloroformate afforded methyl phenylacetate 1, methyl o-toluate C 2j and, in addition, a trace of dimethyl homophthalate C 3. The formation of C 2D decreased with increasing basicity of the solvents in the order: Et20 THF THF-1-HMPA. The diminished yield of C2D was obtained also in the reaction of benzyllithium which has higher ionic character of the C-M bonds relative to the Grignard reagent. The formation of o-toluate C2 decreased in the order of the reactivity of alkyl chloroformates; C1COOCH3 C1COOC2H5, C1COO(CH2)3CH81COOCH2CH(CF18)2 C1C00(Cli2)8CH3. A plausible reaction pathway is proposed on the basis of these findings.

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The reaction of 5-methyl-1, 3-cyclohexanedione with 1-hydroxy-2-propanone in the presence of zinc chloride to give (±)-evodone was examined in a benzene, dichloromethane, or meth- anol solution at room temperature or at reflux temperature. When the reaction was carried out in benzene at room temperature, (±)-evodone was obtained in 59% yield (the yield based on the consumed diketone: 84%).
The reaction of ethyl acetoacetate with 1-hydroxy-2-propanone in the presence of zinc chloride was also investigated. The reaction in boiling ethanol or benzene gave ethyl 2, 4-dimethyland 2, 5-dimethyl-3-furancarboxylates, while the reaction in boiling methanol gave only the 2, 4-dimethyl isomer.

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