In order to make clear the influence of the surface structure of cadmium series pigments on their dispersion properties, the heat of immersion of CdS-ZnS. pigments was measured and was compared with their degree of dispersion in plastics. Of all the CdS-ZnS series pigments studied, the heat of immersion of the a-type (hexagonal) samples was 900-960 erg/cm² in water and 220-330 erg/cm² in benzene, and that of the 8-type (cubic) ones was 420-500 erg/cm² in water and 320-440 erg/cm² in benzene. These results indicate that the β -type crystal is more oleophilic than the a-type one and explain the fact that the 8-type crystal is better disperesed in plastics.

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Hydrogenation of phenol catalyzed by Pd/C suspended in cyclohexane was studied kine-tically and a most adequate rate equation was presented by assuming Langmuir-Hinshelwood model. The product distribution and the effects of hydrogen partial pressure on initial rate were measured as shown in Figs.5, 6 and 7 under the conditions that mass transfer effects were negligible. As seen from Fig.5, cyclohexanone formed selectively at first and the formation of cyclo-hexanol was negligible until the starting phenol was nearly completely consumed, so that the reaction was analyzed as two independent reactions (phenol → cyclohexanone and cyclohexanone → cyclohexanol). Assuming Langmuir-Hinshelwood or Rideal-Eley mechanism and taking into account not only the initial rate but also the change of concentration of phenol with time, the most adequate rate equations for reaction (I) and (III) were determined as Eq. (16) and Eq. (17), respectively, by means of linear or nonlinear least squares methods. Validity of these equations are demonstrated by the agreement between the experimental and calculated values as shown in Figs.5, 6 and 7. The apparent activation energy of the reaction and the heats of adsorption of hydrogen and phenol were obtained from the temperature dependency of the constants in the rate equations. The reaction mechanism based on the kinetic studies was proposed.

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Hydrogenation of aniline with Ru-Pd and Ru-Pt alloy catalysts supported on activated carbon was investigated under an atmospheric pressure of hydrogen in the temperature range from 30° to 60° C. Under these conditions the pure Ru and pure Pd catalysts had very low activity for this reaction, but the alloy catalysts of these metals were active and in these alloy series a maximum activity appeared at about 25 atom% of Ru content. At the maximum point the activity was about 15 times as great as that of the pure Pd catalyst which was prepared by the same method as these alloy catalysts. The selectivity for cyclohexylamine increased by 15 mol% as compared with that of pure Pd at the composition of 25% Ru. In order to study the influence of the amino group of aniline on the hydrogenation of the benzen ring, benzene was hydrogenated with these alloy catalysts. For this reaction a maximum activity appeared at about 75 atom% of Ru content. On Ru-Pt alloy series, the hydrogenation of aniline did not show a maximum activity and the activity decreased greately when Ru was added to Pt. On this Ru-Pt series, the selectivity for cyclohexylamine changed almost linearly between the both pure metals. The hydrogenation of benzene with this alloy series was also studied. This alloy catalysts had higher activity than that of the pure metal when the reaction was carried out at 30° C. On both Ru-Pd and Ru-Pt alloy series, the compensation effect for the hydrogenation of aniline was recognised except the pure Ru catalyst. The activity and selec-tivity of the catalysts which were prepared by the deposition of a small amount of Ru on Pd or Pt metal surface, were also investigated.

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Heterogeneous catalytic reaction of a-picoline in a stream of hydrogen at 280-380° C has been investigated over Co-MgO (1: 2.8) catalyst to elucidate its reaction mechanism. A pyrex-glass tube reactor of continuous flow type was used at atmospheric pressure, equipped with a micro-feeder and a product trap. The products consisting of pyridine, 2, 6-lutidine, ammonia, and methane, were analyzed by gas chromatography and titration. With regard to the reaction occurred at 300-360°C, a close correlation between 2, 6-lutidine yield(Y) and ammonia yield(X) was obtained as shown in the following linear equation, Y= 0.706X+ 1.5 (mol%) The initial rates of formation of ammonia, 2, 6-lutidine, and pyridine at 300° C were obtained as 8.8 x 10-3, 9.9x 10-3, and 6.2x 10-3 mol/g-cat. hr, respectively. In particular, under the reaction conditions of 0.33-0.97 atm. of partial pressure of hydrogen and at 300° C, interrela-tion between the rates of 2, 6-lutidine and ammonia formation was obtained, approximately, as follows: r2, 6-L = rNH3 -8.0 x 10-4 (mol/g-cat. hr) From these results, it is concluded that the 2, 6-lutidine farmation proceeds with consecutive mechanism bringing about ammonia formation by hydro-cracking of pyridine ring as the first step.

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An uranium-antimony oxide catalyst, claimed in the patents for the oxidation of propylene to acrolein, has been investigated from a standpoint of structure and activity relationships. Catalytic activity tests were carried out by a flow system and a pulse reaction method. X-ray pattern, D. T. A. -T. G. A. curve and low frequency infrared spectrum of the U-Sb binary oxide catalyst system were measured for characterizing the catalyst structure. The following con-clusions were obtained. (1) High selectivity of propylene to acrolein in excess of 70% was achieved over the catalysts with a lower atomic U/Sb ratio than 4/6 and those calcined at high temperatures above 700° C. (2) The formation of double oxide (USB3010) was observed by calcination at about 620° C. On the basis of direct relationship between calcination of tem-perature above 700° C and appearance of catalytic activity for selective acrolein formation, we recognized USb3O10 as the active component of catalyst. (3) From the experiments of reducing catalyst with propylene pulses and reoxidizing catalyst with oxygen pulses, several interesting informations on the catalysis were obtained.

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Anodizing of Al was carried out in oxalic acid-oxalate solutions over the pH range from 1.7 to 6.4 at constant anodic potentials and variation of the anodizing current, the structure of the film and the amount of dissolved Al ions were observed with time. The current-time curve was divided into four successive periods of a, b, c and d in relation to the surface struc-ture of the film. In the initial period of anodizing (period a), the current falls nearly expo-nentially with time in accordance with the growth of the barrier layer. After a certain period of time the lowering of current ceases (period b) and the current begins to increase with time (period c) and finally reaches a steady value (period d), owing to the pore initiation and the growth of the porous layer. It was found that an appreciable amount of film dissolves even in the period a; the rate of dissolution is affected strongly by the anion species in the solution but scarcely changes with the pH of the solution. A high rate of dissolution observed at periods c and d increased remarkably with rise of anode potential and with fall of pH. This is explained in terms of the mechanism which assumes the formation of cation defects at the outermost part of the barrier layer and their interaction with protons in the solution. A new method of determining the barrier layer thickness of the porous type film was proposed.

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Various kinds of reaction products were obtained on dehydration of mixtures of NaH2PO4 2H20 and H3B03 with various mole ratios by heating at 400-750° C. The products were. subjected to chemical analyses, IR spectrophotometric measurements and DTA. When a mixture of 3 moles of NaH2PO4 2H20 and 2 moles of H3B03 was heated at 400-400° C, a new compound containing macromolecular chains with a skeleton of B-O-P linkages was considered to be formed; the obtained compound was light, finely-divided and sparingly soluble powder and its mp was about 700° C. When initial mixtures had a mole ratios of NaH2P04.2H20 to H3B02 other than that of 3: 2, the reaction products consisted of some complicated polymers characterized by the formation of B-O-P linkages. In the cases of the glassy products with n value of 9-18, their water-soluble parts showed the ortho- pyro-: tri-: high polymeric phosphoric acid ratio (in P205) to be 1: 4: 2: 2 (n-6); here, n refers to a mole number of NaH2PO4.2H20 mixed with 2 moles of H3B03. The addition of a small amount of H3B03 to NaH2PO4.2H20 showed the tendency that the thermal conversion of NaP03-(II) into Na3(P03)3 was appreciably prevented.

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The decomposition equilibrium of WCl₆ in the gas phase and some thermodynamic properties of WCl₅ were studied. Electronic spectra of gases produced by sublimation, evaporation and decomposition of these substances were measured. The vapor pressure of WC15 was measured by a Bourdon-type manometer. Absorption bands in gas phase were observed at 39.2, 30.8, 27.0 and 23.2 kK for WCl₆, at 42.6, 36.4, 28.2 and 12.1 kK for WCl₅ and at 31.7 kK for W₂Cl₁₀. It was confirmed from the change of electronic spectra of WCl₆ on heating that tungsten hexachloride decomposed above 240°C according to the chemical equation, WCl_6(g) =WCl_6(g) + 1/2 Cl_2(g). The equilibrium cons-tant of the above reaction was given as log K=-4.46 X 10³/ T+ 5.66 (240-466°C). The sublima-tion pressure (P_sub) and the evaporation pressure (P_evap) of WCl₅ were given by the following equations : log P_sub (atm) - 4.11 x 10⁸/ T+ 7.41 (150-251°C), log P_evap (atm) = 2.77 X 10³/ T+4.85 (251-287°C). The equilibrium constant of the reaction, W₂Cl_10(g) = 2 WCl_6(g) was given as log K= -1.35 x 10³/ T+ 3.47 (256-480°C). From these results, the following thermodynamic values were obtained;ΔG⁹dec, =20.4X 10³-25.9T cal/mol, zilidec=- 20.4 kcal/mol and ΔSdec=25.9 cal/deg mol for the reaction, WCl_6(g) =WCl_5(g)+1- 1/2 Cl_2(G)Δ ; G⁰sub = 18.8x10³-33.9T cal/mol, ΔH_sub= 18.8 kcal/mol and ΔS_sub= 33.9 cal/deg.mol for the reaction, WCl_5(g) = WCl_5(g) ; ΔG⁰_evap = 12.7X10³- 22.2 T cal/mol, ΔH_evap= 12.7 kcal/mol and ΔS_evap= 22.2 cal/deg. mol for the reaction, WCl_5(g) = WCl_5(g) and ΔG_diss= 6.18 X 10³-15.9T cal/mol, ΔH_diss= 6.18 cal/mol and ΔS_diss= 15.9 cal/deg.mol for the reaction, W₂Cl_10(g) = 2 WCl_5(g).

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Surface structure changes of alkali halides crystals on adsorbing water vapor molecules in multilayer have been studied by means of X-ray powder diffraction. Effects of particle size and some surface properties of the salts on the intensities of X-ray diffraction by the concerned samples were examined. Three salts, KI, KBr and KC1, were adopted as samples, and their evaporated films, fine crystals and powders ground to 200 mesh were prepared and used. The multilayer adsorption of water molecules on the salt results in a formation of the hydrated ions. At that time it is found that both the su-rface state and the X-ray diffraction intensity change and caking of the salt appears. The intensity of X-ray diffraction by the salt with low crystallinity, such as evaporated films of KI and KBr, increased above the vapor pressures of water molecules forming the hydrated ions. This fact might be attributed to a rearrangement of the surface ions. On the contrary when the salt had a high crystallinity, the depression of the diffraction intensity appeared in the vapor pressure range. The value of the vapor pressure at which adsorbed water molecules act to form the hydrated ions was peculiar to the material. Their values are 40, 51 and 55%rH for KI, KBr and KC1, respectively. From the above results it may be expected that X-ray diffractometry is an effective method for detecting formation of hydrated ions on a salt and for studying its caking-process.

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Antimony-doped stannic oxide film was prepared as follows; butanol solution of stannous caprylate containing di-isoamyloxy ethoxy antimony was coated on a glass substrate, and dried at room temperature for thirty minutes. The resultant film was dried at 110° C in a drying oven for thirty minutes, then it was heated in a electric furnace at the temperature up to 200-600° C for twenty minutes. The film formation process was examined by thermogravimetric analysis, infrared spectro-metry, and X-ray diffraction and electron diffraction methods. The effects of the amounts of antimony oxide and coating-heating repetition on the electric resistivity of prepared film was also examined. When a film of organic stannous compound solution was dried at 110° C, it showed an iridescent interference color and an amorphous stannous oxide phase deposited in it. This amor-phous stannous oxide phase change to crystalline stannic oxide phase by heating at 350° C. The higher the antimony oxide content in the film, the higher the changing temperature of stannous oxide to stannic oxide and the deeper the blue color of prepared film. The film became harder by heating at a temperature above 400° C. Surface resistivity of undoped stannic oxide film was about 6 meg-ohm at room temperature showing non-metallic conduction. In the case of the antimony-doped stannic oxide film, however, the surface resistivity was about 5-50 k-ohm at room temperature showing metallic conduction. The resistivity of the latter film was reduced remarkably by the repetition of coating and heating procedure.

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The silver-glaze of smoked tile is so far considered to be high grade graphite deposited on surface. The electric resistivity of the surface of the samples made in Fukaya district is measured. Its value is essentially higher than that of artificial graphite. X-ray diffraction and electron diffraction studies on surface carbon chemically scrapped off from tile-body reveal that this carbon layer is not highly crystalline but amorphous. Observation by scanning electron microscope also shows that the deposited carbon has characteristics of pyrolytic carbon. On the basis of these experimental studies, it is concluded that the carbon deposited on surface of smoked tile is not high grade graphite but pyrolytic carbon with turbostratic structure.

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The authors designed a special ball mill made of Pyrex glass for the determination of micro amounts of water released from rock sample during mechanical grinding (Fig.1). A set of balls which is made up of 4 balls of g5 16 mm, 30 balls of 13 mm and 4 10 mm, and 200 balls of 4 5 mm and rocks sample of uniform grain size (1.00 to 0.84 mm) are placed in the ball mill. The ball mill is connected with a cylinder of nitrogen gas, silicagel-P205 drying tubes, gas flow meters and a Karl Fischer titration vessel by a glass and copper pipes, as shown in Fig.2. An adsorbed water in the ball mill is expelled by passing the dried nitrogen gas. After taking off the ground glass joints a, e and f from the ball mill, the ball mill was placed on a revolving holder and rotated at 120 rpm more than two hours. When the ball mill is revolved for 120 minutes, 99.2% of 10 g of a basalt samples are pulverized to pass through a 0.044 mm (325 mesh) testing sieve. It is confirmed that con-tamination of the ball mill with the atmospheric moisture is negligibly small during a five hours run. After pulverizing the sample, the. ball mill is connected with the Karl Fiscer titration vessel in the same way as the prescribed procedure. The water released from rock sample during grinding is transported by flowing the dried nitrogen gas with constant flow rate to the Karl Fischer titration vessel and absorbed into an anhydrous mixture of methyl alcohol and ethylene glycol (1: 1). After that the mixture was titrated by Karl Fischer method. The accuracy is confirmed to be ± 0.02 mg H2O. The amounts of water released from the most usual fresh volcanic rocks and from many glassy rocks was determined to be less than 0.0001%. This value may be considered negligible. The rocks including so-called"residual magmatic water"and highly hydrated glassy rocks released large amount of water. If the water released on mechanical grinding are disregarded, the amounts of water in the rocks can not be correctly evaluated. Liparites, from Nii-shima and Kozu-shima, absorbed even an extremely small amounts of water which remained in dried nitrogen gas during mechanical grinding and analytical procedure.

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Atomic masses (A) of the most stable nuclides are generally led by linear summations of a pair of proton and neutron (p - n) for nuclides whose atomic numbers (Z) are below 30 and p - n n for those above 30Z nuclides. Binding energies (b. e.) are calculated in conformity of it, and additions of 4b. e.14Z to b. e. of deutrium or tritium, according to whether Z are even or odd, give those of the first 20Z nuclides. LIB. e.14Z are averaged 18 Mev below 20Z and 20 Mev above 25Z, which approximately correspond with binding energies per proton (b. e. p. p.). Binding energies per nucleon (b. e. p. n.) bear the maximum value around 25Z, since b. e. p. n. = b. e. p. n. Z/A. Neutrons increase after additional formulae: 2n are required to combine with every accumulation of lop between 20Z and 40Z nuclear groupings, while neutrons, accumulated beside p n during a compilation of 10 nuclides, are not transferred to the next coming 10Z group before 50Z nuclide is completed. These formulae are crossed with several features in stabilizing nuclides, magic numbers and others. On the basis of these findings the alpha particle theory is hardly acceptable and the coefficient of surface tension in the Bethe equation is found to be overestimated.

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For the production of ⁵⁴Mn by the α- and ³He-particle reactions on natural chromium, their excitation curves and thick-target yields were measured. Also various conditions in the production procedure, especially the chemical separation of manganese in a hydrochloric acid solution of the bombarded target after the removal of ⁵²Fe were examined. A stack of thin chromium plates was bombarded by α- or ³He-particles beam of 44 MeV maximum energy, and the manganese activities were measured nondestructively or after the chemical separation. The excitation curve of the α-reaction shows a maximum of 490 mb near 30 MeV energy, and that of the ³He-reaction, a maximum of 80 mb near 18 MeV. The thick-target yields for 40 MeV incident energy are 6 μCi/μAhr and 1.1, μCi/μAhr for the α-reaction and the ³Hereaction, respectively. The α-reaction thus proved to give a higher yield of ⁵⁴Mn than the other possible reactions. The bombarded chromium target was dissolved in a hydrochloric acid solution (8 N) from which the ⁵⁴Fe was removed by an extraction method. The remaining solution was saturated with a pure HC1 gas in such a way to bubbling it through the solution, from which almost all the non-radioactive chromium and other byproduced active contaminants were removed by an anion exchange method. The manganese solution thus obtained was evaporated to dryness, and the Cl^--free residue was dissolved in 50 ml of 10 mol/l H₂SO₄ together with 2 g of KIO₃. And then from the resulting solution the Mn was distilled out as Mn₂O₇ into a trap containing a small amounts of dilute HCl solution plus H₂O₂. To maintain the solution at 10 mol/l of sulfuric acid concentration and 166°C which is the optimum conditions for distillation, azeotropic nitric acid vapour (120.5°C) was added gradually into the boilling solution. The ⁵⁴Mn was obtained in carrier-free state. The chemical yields over all the chemical procedure proved to be >90% with a sufficient radiochemical purity. The production method of ⁵⁴Mn via the α-reactions on natural chromium proved to be superior in higher yields and some other reasons to other possible reactions.

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Acid hardening of resol type phenolic resins are used in adhesives for wood working. abrasives and other several fields. Mechanisms of the reaction had been studied by several workers, but there were almost no work published in which instrumental analysis were used. In this papar, mechanisms of acid hardening of phenolic resins were studied by infrared spectrometry. Resol type phenolic resins were prepared by the use of NaOH catalyst, and their mole. ratios (F/P) were 1.0, 1.5, 2.0. The samples were acidified by 1 N HCl. Heating temperatures were 60 and 120° C. To follow the reaction quantitatively, intensity ratio method was used taking the 1610 cm^-1 band as intensity standard. The results were as follows.1.60° C hardening The main reactions were formation of methylene linkage (active p-position+methylol group) and dimethylene ether linkage (methylol group+methylol group). Small amount of carbonyl group was detected, which formed by the oxidation of methylene linkage.2.120° C hardening Samples of mole ratio (F/P) 1.5 and 2.0: The reactions were divided into two stages. At the first stage, formation of dimethylene ether linkages was remarkable. At the second stage, dimethylene ether linkages were decomposed, and phenolic hydroxyl groups decreased. At this stage, formation of quinone and quinone methide type carbonyl groups was suggested. Absorption intensity at 1650 cm^-1 (carbonyl group) increased remarkably. Sample of mole ratio (F/P) 1.0: At early stage, methylol group and dimethylene ether group disappeared, and after that intensities of out of plane deformation band of benzene rings were almost unchanged. Carbonyl group was made mainly through the oxidation of methylene group.

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The application of polarogphic method to the CHCl₃-extract of the ternary complex composed of Hg(II), Cl- and pyridine(py) is studied. Mercury(II) reacts with chloride ion in the presence of pyridine and forms the ternary complex HgCl₂py₂. The complex is extractable into chloroform in the pH range from 5.5 to 6.5. The ternary complex can be reduced at the dropping mercury electrode and the reduction wave is applied to the determination of mercury(II). At first, mercury(II) is extracted into chlorofrom as the ternary complex HgCl₂py₂. The 6 N HNO₃, the most suitable supporting electrolyte solution, and methylcellosolve, the mixing solvent, are added to the chloroform extract. This ternary mixture is employed as the polaro- graphic electrolyte solvent. In the AC polarographic method, it is unnecessary to purge dissolved oxygen. The reduction of the ternary complex HgCl₂py₂ may be considered to proceed in one step involving the addition of two electrons, as shown by HgCl₂py₂ + 2e^- Hg↓ + 2Cl^- + 2 py The half-wave potential of this wave is about +0.18 V vs. SCE. The plot of log{i²/(i_a-i)} against potential E is linear and has a slope of 30 mV at 20°C. The limiting current i_d is proportional to the root of the height of the mercury column. Consequently, the electrode reaction is reversible and diffusion-controlled. The relative temperature coefficient of i_d is 1.44% deg^-1 at 20°C. The available range of the present method covers from 0.2 mg (5 x 10^-5 mol/l) to 1 mg (3 X 10^-4 mol/l) of mercury (II) in 20 ml of sample water and the time required for a single deter-mination is about 30 min. Cu²⁺, small amounts of Fe²⁺ and Fe³⁺ do not interfere, but I^-, Br^- and SCN^- interfere.

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Ion exchange separation of gadolinium, europium, samarium, neodymium and praseodymium was studied using mixed solutions of methanol-acetatic acid-nitric acid, and those five rare earths we the Amberlyst-A 29 (nitrate form). The rare earths described above were strongly adsorbed on the top of the column from solutions consisting of 90% methanol, 5% glacial acetic acid and 5 % 7 mol/l nitric acid. Then, Gd, Eu, Sm, Nd, and Pr were eluted in this order by passing successively the four kinds of eluents : (flow rate : 0.7.0.8 ml/min)
( 1 ) MeOH-17 mol/l HOAc-7 mol/l HNO₃ (volume ratio : 90 : 5: 5).
( 2 ) MeOH-10 mol/l HOAc-7 mol/l HNO₃ (80 : 15 : 5).
( 3 ) MeOH-8 mol/l HOAc-7 mol/l HNO₃-H₂O (75 : 15 : 5: 5) and ( 4 ) H₂O.
It is confirmed that up to 0.007 mmol of Gd, Eu, Sm, Nd, and Pr are satisfactorily separated with a column of 1.1 cm diameter and 21 cm length.

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To obtain the temperature dependency of reaction kinetics and heat of reaction in liquid phase from single experiment instead of several runs at various temperatures, a new calorimetry that is carried out with the " Triplet Calorimetry" operated at rising temperatures is developed. The calorimeter consists of three equivalent jacketed-vessels (1000 ml stainless autoclaves) each of which has an agitator, a thermocouple and an internal heater. The first is used for reference, the second for reaction analysis, and the third for compensation of equipmentfactors by means of periodic step responses with the internal heater during the reaction. The heat transfer medium is heated at constant rate and is recycled through medium heater and each jacket. Film coefficient of outer side of vessel wall may be influenced by the effect of rising temperatures. So the coefficients of three vessels must be equal with one another by means of flow control of the medium. Applying this calorimetry to the analysis of hydration of acetic anhydride in 70% aqueous acetic acid solution, Q = 13.60 ± 0.5 kcal/mol and k= 7.89 x 107 exp (-15.8 x 103/R T) sec-1 under n=1 were obtained in the range of 20-40° C.

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A simple and efficient analytical method is described for determinations of higher normal paraffins, normal oleffins, and α -olefins. Such olefins which contain paraffins were converted to the corresponding alcohols by hydroboration-alkaline hydrogen peroxide oxidation. The mixture of paraffins and alcohols was analyzed by gas chromatography. From this datum, the amounts of paraffins and olefins were calculated. Further, the ratio of α -olefin to inner olefins was determined from that of 1-alcohol to inner alcohols. The composition obtained by this method was in excellent agreement with that of the known samples, as indicated in Table 7. A mixture of straight-chain paraffins and olefins which were separated from a thermally cracked Kuwait crude oil by urea adduct procedure was analyzed by the method, and the analytical result was listed in Table 9.

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Cyclohexanone was irradiated with γ-ray in the presence of some chlorinated hydrocarbons. Main products were confirmed to be 2-(1-cyclohexenyl)cyclohexanone [1] and 2, 6-di(1-cyclohexenyl)cyclohexanone [2]. Any expected condensation product between cyclohexanone and chlorinated hydrocarbons was not detected. The rates of formation of [1] and [2] were found to be nearly proportional to the dose rate. Maximum yield of 47.5% of [1] was obtained in the presence of 20% moles of tetra- chloroethylene. Effect of the coexistence of chlorinated hydrocarbons on the yields of [1] and [2] decreased in the order: tetrachloroethylene> trichloroethylene> cis-1, 2-dichloroethylene, carbontetrachloride> chlorgform> methylenechloride>1, 1-dichloroethane. mkhanism on the forniation of [1] and [2] was discussed.

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In the liquid-phase hydrogenation of 2-ethylhexanal over nickel-kieselguhr under pressure, 2-ethylhexanal(di-2-ethylhexyl) acetal is produced in the equilibrium state between 2-ethylhexanal and 2-ethylhexanol, as shown in the following scheme; [2-ethylhexanal] + 2[2-ethylhexanol] [2-ethylhexanal (di-2-ethylhexyl) acetal] + [H₂O] Equilibrium constant of the acetal formation was measured at various temperatures and the enthalpy of formation was found to be -10.6 kcal/mol. It was also found that the hydrogenolysis reaction of 2-ethylhexanal(di-2-ethylhexyl)acetal over the nickel-kieselguhr catalyst is of the first order reaction and activation energy of the reaction is about 10.2 kcal/mol. Effect of organic acids and water as additives on the reaction rate of 2-ethylhexanal hydrogenation and on its side reaction was studied.

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A systematic separation of natural raw waxes, carnauba wax, candelilla wax and bees wax, has been carried out and the results of the pattern-analysis of their components are described. Both non-aqueous media anion exchange resin column and silicagel column chromatography under 45° C were used for the isolation, and the method of systematic analysis was established. The isolated substances were characterized by IR, TLC etc. The distribution of carbon chain length was determined by use of the programmed temperature gas chromatography on SE-52 as liquid-phase. Their carbon chain length was determined by the method (advanced method of vapour-phase hydrogenation and gas chromatography) developed by us in the previous paper. It was found in this study that each raw wax showed its characteristic distribution of carbon chain length.

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Cationic dyes containing primary to quaternary amino groups undergo complex arid dissocia-tion reaction. There are several molecular species of cationic dyes in each pH region. By the use of a model cationic dye, bis(m-nitrobenzyl) amine (BNB) which showed a simple spectral change at various pH, the dyeing mechanism of acrylic fiber was investigated in detail at various pH by the cylindrical film roll method at 95°C. The acid dissociation constant of BNB was determined spectrophotometrically to be 7.4 in aqueous HC1-CH3COONa (ionic strength I=-0.1) solution at 25°C. Both cationic and non-ionic species, [2] and [1] of BNB are present in a neutral or a weakly acidic aquous solution (Equation ( 1 )). On the other hand, acrylic fibers have two kinds of dyeing sites, strong acid groups from the fragment of polymerization catalyst or from a monomer, and weak acid groups. The amount of effective dyeing stites in acrylic fibers changed at various pH, as shown in Table 1, which was confirmed by the pH dependence of the adsorption of [2] (Fig. 2). In the dyeing of acrylic fibers, there are three kinds of dyeing mechanism, which work simultaneously at various pH (Table 2). The adsorp-tion isotherms of [1] and [2] were obtained at pH 1.5, 4.2 and 6.8 (Fig. 1). The adsorptions of [1] and [2] were also measured over pH range from 0.2 to 6.8 (Fig. 2). The concentration distributions of [1] and [2] for the diffusion in polyacrylonitrile were obtained at pH 5.0, 6.0 and 6.8 (Fig. 3-6). At pH lower than 4.2, the distribution of [2] was exclusively obtained. The contribution of various dyeing mechanisms was discussed by these results. It may be concluded that the acid dissociation reaction of BNB does not occur in acrylic fibers.

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Acidic components of S. altissima roots were methylated with diazomethane and repeatedly chromatographed on silica gel to give two oily bitter principles [3] (C₂₆H₄₀0₄, bp 180-190° C/ 0.01 mmHg) and [4] (C₂₆H₄₀0₄, bp 190-195° C/0.02 mmHg), and one crystalline bitter principle, methyl altissimate, [16] (C₂₁H₃₂0₃, bp 108-109° C). Upon reduction with LiAlH₄, [3] gave the diol [5] and seqcis-2-methyl-2-butenol-1 [8], and [4] gave the same diol [5] and seqtrans-2-methyl-2-butenol-1 [7]. The acetylation of [5] gave the monoacetate [9], which was oxidized with Jones' reagent, and reduced by the Huang-Minlon method to give kolavenol [12]. The monoketone [14] derived from [5] possessed two active hydrogens in the α position of the carbonyl group. Methyl altissimate [16] was identical with the neutral product obtained from chromic acid oxidation of methyl kolavenate Based on the above chemical evidences and the spectral properties of derivatives, it was determined that [3], [4] and [16] were methyl 6-angeloyloxykolavenate, 6-tygroyloxykolavenate and 2-ketokolavenate, respectively.

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Free radicals produced by γ -irradiation of vinyl acetate in the solid have been studied with electron spin resonance (ESR) and the changes of these radicals on the visible light irradiation have been also examined. An oriented solid of vinyl acetate was prepared for ESR measurement by the solidification of vinyl acetate around an aluminum rod at -196° C or -117° C and with subsequent γ -irradiation (dose; 8 X 106 rad) at -196° C. The oriented crystalline solid prepared at -117° C gives an ESR spectrum consisted of a singlet and additional adsorptions in the dark at -196° C. After irradiation of visible light for 10 minutes, ESR spectra of oriented crystalline solid exhibit a distinct hyperfine structure and a definite anisotropy on the rotation of the solid in the dc magnetic field. These spectra consist of a quartet (A1 =12.5 G), an anisotropic triplet and an equivalent four lines (A1=103 G, A2=16 G), corresponding to the radicals, CH, COO3COO., . H2COOCH=CH2 and CH2=C H, respectively. The prolonged irradiation with visible light for 300 minutes yields the apparent five lines, consisted of a pair of triplet (A1=10 G, A2=20 G) and the above-mentioned triplet corresponding to the radicals CH2CHO and CH2COOCH=CH2, respectively. The spectrum of the r-irradiated glassy solid prepared at -196°C consists of strong four lines which is confirmed to be isotropy and of a weak doublet splitted by 120 G, corresponding to vinyl radical. Irradiation of the glassy solid with visible light for 30 minutes gives a sharp quartet (A1=23 G) assigned to CH3. produced by the photolysis of CH3C00., A broad triplet (A1 =22 G) becomes to be observable on elevation of the temperature to -160° C and remains up to -100° C. This triplet is assigned to CH2COOCH= CH2. In conclusion, both the crystalline and the glassy solids produce the same radicals on γ -irradiation.

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The treatment of sewage with granular activated carbon is a promising method for the recovery of water. The most suitable conditions for regeneration of carbons used for the clarification of sewage after activated sludge treatment was investigated. The carbon samples used for the sewage treatment in the conditions of Table 1 were heated with a thermobalance (Fig.1) in an atmosphere of nitrogen mixed with 0-10% oxygen. The adsorption properties of the regenerated carbons were compared with the virgin carbons in terms of the adsorption rates and isotherms of methylene blue or sodium dodecylbenzenesulfonate. The weight of the carbons used for the sewage treatment decreased rapidly at 100°C to 550°C in compliance with the desorption of the contaminants (Fig. 2). The adsorption properties of the regenerated carbons, which were heated in nitrogen for 10 min. at a constant temperature in the range from 200°C to 600°C, are compared with the virgin carbons (Fig. 3-5). Those of the regenerated carbons heated above 550°C were equal to the virgin carbons. The con-taminants desorbed equally in pure nitrogen and in nitrogen containing oxygen, but the activated carbons were decomposed by the oxidation above 400°C in the atmosphere of nitrogen containing oxygen (Fig. 6). The rates of this decomposition are expressed by the next equation, d Wt/dt=kWt(02)n where Wt is weight of carbon at time t. The decomposition rates of the carbons used for the sewage treatment were faster than the virgin carbons (Fig 7-9). The effect of the oxygen concentration on the decomposition rates of the carbons used for the sewage treatment was smaller than the virgin carbons (Fig. 10-42), but the activation energies of the decomposition reaction showed only a slight difference (Fig. 13). The oxygen concen- tration had little effect on the adsorption properties of the regenerated carbons (Table 3).

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The muscarine-like activity of acetylcholine(Ach) and 2-aminoethanol(ETA) derivatives and the acute toxicity of tropolone(TRP) derivatives were discussed on the basis of the molecular orbital theory. The order of the activity of Ach and ETA derivatives is in agreement with that of the nucleophilic reactivity index, fr(N) of the nonbonding, vacant p2-orbital of the central atom (N+, P+, or As+) in the onium group. The activity in the acute toxicity of TRP derivatives is explained in terms of the nucleophilic reactivity index, DR(N)= _??_ _??_ fr(N4), of the vacant π -orbitals.

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The half wave potentials of 6-phenylfulvene, 6-methyl-6-phenylfulvene, 1-benzylideneindene, 9-benzylidenefluorene, and their derivatives with p-methyl, p-methoxy, and p-N, N-dimethylamino substituents on the phenyl group were studied in relation to the lowest vacant molecular orbital energies which were calculated on the basis of the LCAO-MO methods. The parameters of coulomb and resonance integrals for hetero atoms which were proposed by Streitwieser and Zweig were adopted. The linear relationship between the halfwave potentials and the lowest vacant molecular orbital energies by HMO method gave the correlation coefficient of 0.959. Furthermore, the results using 0.9β and 1.1β as resonance integrals for essential single bonds and essential bouble bonds, respectively, in HMO calculations gave better linear relationship with correlation coefficient of 0.992.

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Cadalene, a dehydrogenation product of some sesquiterpenes, was synthesized as follows. p-Methylacetophenone [1] was converted into 4-(p-tolyl)valeronitrile (9) passing through diethyl 2-(1-p-tolylethyl) malonate [4] (bp 142° C/2 mmHg). The action of Grignard reagent on[9]yielded 2-methyl-6-(p-tolyl)-3-heptanone [12b] (17.4%, by 154-165° C/15 mmHg), which was cyclized to 1, 6-dimethyl-4-isopropyl-1, 2, 3, 4-tetrahydronaphthalene [14b] passing through the alcohol [13 b]. Cadalene [/5 b] was obtained by dehydrogenation of [14b] and also of the isopropylation product of 4, 7 -dimethyl-1, 2, 3, 4 -tetrahydronaphthalen-1 -one [11] with sulfur. Similarly, 5-(p-tolyl)-2-hexanone [12a] (36.8%, by 110-115° C/4 mmHg) afforded 1, 4, 6- trimethylnaphthalene [15 a].

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