Among a number of theoretical formulae Eq. (4)∼(7') proposed hitherto for the freezing-point depression of capillary liquid, the authors' formula Eq. (6) is the most general one because the contact angle is taken into account. All the formulae cited here, however, give only the limiting temperature T_f, at which the meniscus surface of the capillary liquid condensing in pores of radius r_f commences to freeze (Fig.3-b).
The effective contact angle Θ as well as the radius of conical pore has been defined with relation to the radius of curvature of menisci by Eqs. (2) and (3). The conical-pore model presented here may be generalized for any type of pores in porous materials. By using these new concepts, a model of freezing phenomenon has been proposed. Frozen layer formed initially in gas-liquid interface, with non-zero value of Θ_SG, is thickened keeping Θ_SG constant, as the temperature decreases (Fig.3-c). On the basis of Laplace's and thermodynamical equations in the three phase equilibrium of the sorbate in pores, a theoretical formula Eq. (18) has been derived. The formula relates the radius of curvature of solid-liquid interface to temperature T, and is easily applicable to the calculation of the amount of the sorbate melted during temperature rise, if the distribution of the pore size is known. Heat capacity curves calculated (Figs.4, 6, 7, 8, 10 and 11) are in fair agreement with the experimental results of Morrison et al. or Antoniou. The values of solid-gas or solid-liquid interfacial tensions and effective contact angles have also reasonably been determined (Tables 1, 2 and 3).
Anomalous excess heat capacity of the condensate, which remained so far without a reasonable explanation, is satisfactorily interpreted by the, capillary condensation theory.

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The surface of silica gels was treated in the following way: the silica gels soaked into the hexane solution of various alcohols, i. e., saturated linear, branched chain, phenyl and unsatu- rated alcohol as well as several dioles, were allowed to react with them in autoclave under high pressure and at high temperatures, (pulled out from) the vapour at or near the temperature of critical point of hexane, and washed with alcohol or benzene and hexane. It was confirmed that (1) these surface-treated silica gels were organophilic, except the gels treated by diole, on the basis of the preferable property of dispersion toward the mixed media like water-benzene, (2) the surface groups attached on silica gel were assigned as the alcoxy group through the elemental analysis and the surface area calculated from argon adsorption isotherm at 77°K: and the silica gels treated with the unsaturated alcohol still kept the double bond character, (3) silica gels showed hydrophilicity after the treatment with diole, since one of the hydroxyl groups of diole reacted with a silanol of the silica gel and (4) silanols of the silica gel did not react with the tertiary alcohols like tert-butanol or tert-pentanol.

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It is well known that the differential thermal analysis (DTA) is very useful for investigating a thermal change, for instance the phase transition. We have constructed a modified DTA apparatus with high sensibility capable of measuring the properties of the polymer solutions and solids. Using this apparatus, the melting temperature of the D-and L-mandelic acid with various composition (D-L systems) and DL- and L-mandelic acid with various composition (DL-L systems) have been estimated on the basis of the analyses of DTA curves, respectively.
The temperature-composition diagram of mandelic acid obtained are shown in Fig.3-1 for D-L system and in Fig.3-2 for DL-L system, respectively and the melting temperature of D-L system and DL-L system are summarized in Table 1 and 2, again respectively. Assuming that the melting point depression theory can be applied to the D-L system, we have the following eauation;
where, X is the mole fraction, T., the melting temperature of a pure, T_m, that of a solution containing the sample, ΔH, the heat of the fusion of mandelic acid, respectively. On the other hand, the diagram of DL-L system can be analyzed in terms of Mauser's theory as follows;
where, x₁, x₂ are the mole fractions of the antipodes, ΔH is the heat of fusion of racemate, and T, T are the melting temperatures of racemate and its solution, respectively.
The thermodynamic quantities of the fusion of D-, L- and DL-mandelic acid have been estimated from DTA curves, in Eq. (1) and Eq. (2), and the results obtained are summarized in Table 3, 4 and 5, respectively. The agreement between the heats and entropies of fusion of D-, L- and DL-mandelic acid estimated from DTA curves and those of D- and L-mandelic acid obtained from Eq. (1) as well as those of DL-mandelic acid obtained from Eq. (2) is fairly good. It was found that DTA are very useful for investigating a thermal change, for instance the change in phase of optically active compounds.

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The effect of dopants (Li₂O, Al₂O, In₂O₃, Ga₂O₃) on the oxidation reaction and the electrical conductivity of cobalt(II) oxide were investigated. The kinetic data obtained in the temperature range from 450° to 700°C in oxygen atomosphere were expressed by Jander's equation. The oxidation rate of pure CoO was proportional to Po₂^1/6. The trivalent dopants increased and the monovalent decreased the oxidation rate of CoO. The activation energies for the oxidation of pure and trivalent oxides doped, and Li₂O doped CoO were 33, and 37 kcal/mol, respectively. The effect of dopants on the electrical conductivity conformed to the theory of doping.
These results and the defective structure of the spinel Co₃O₄ suggest that the oxidation rate of CoO is controlled by the diffusion of cobalt ions, Co²⁺, in the spine! layer.

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The interaction between pentaethylene glycol-dodecyl ether(C₁₂E₅) and sodium dodecyl sulfate (SDS) was investigated from the spectra of iodine in aqueous solution containing C₁₂E₅ and SDS. When SDS is added in the aqueous solution of C₁₂E₅ and iodine, the wave length of maxi-mum absorption shifted, and the absorbancy is reduced regularly, with the change of the con- centration of SDS added.
Two break points are observed in the plot of absorbancy against the concentration of SDS added, the first break point being at the 1/10 molar ratio of SDS to C₁₂E₅, and the second break point at the equi-molar concentration. The break points and the slope of the plot indicate that the interaction between C₁₂E₅ and SDS increases rapidly from the concentration. of 1/10 molar ratio of SDS to C₁₂E₅, and that the interaction reaches a miximum at the equimolar concentration.
These trends are observed for various concentration of C₁₂E₅.

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The surface pressure-mean area curves of the mixed monolayers of 1-monostearin and cholesterol as well as 1-monolaurin and cholesterol were measured. In the relation between mean area and mole fraction of cholesterol for both mixed monolayers, negative deviation from the additivity rule of mean area was found to be greatest at a mole fraction of cholesterol of 0.5. The dissolution rate of 1-monolaurin from the mixed monolayer of 1-monolaurin and cholesterol was obtained by measuring the rate of decrease in surface pressure at constant area. Surface pressure of the mixed monolayer, which had been compressed rapidly and held at the constant area, decreased linearly with the square root of elapsed time. The surface concentration of 1-mon olaurin corresponding to each surface pressure was calculated from the relation between mean area and mole fraction of cholesterol. Logarithm of surface concentration of 1-monolaurin varied linearly with the square root of elapsed time as in the monolayer of 1- monolaurin itself. The rate constant of the dissolution of 1-monolaurin decreased when the mole fraction of cholesterol exceeded 0.5.
It was concluded that the complex with one mole of 1-monoglyceride to one mole of cholesterol was formed in their mixed monolayer.

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The oxidation of the reduced solid solution Sr_1-xM_xFeO_2.5+x/2(MY³⁺ and La³⁺) was studied by means of the high temperature X-ray diffractometry and the thermogravimetry. The end member SrFeO_2.5, which is isostructural with the brownmillerite having orthorhombic symmetry, changes to the cubic perovskite-type structure when Sr is substituted for Y in the composition range of 0.15<x<0.25 and for La in the range of 0.30<x<0.60. When the samples were heated at a constant rate in air, the oxidation reaction of SrFeO_2.5 started at 356°C and ceased at 458°C and the structure of SrFeO_2.5 then transformed into the cubic perovskite-type. The increase of the M content in this solid solution lowered both the starting and the ceasing temperature of the oxidation. Oxygen self-diffusion coefficient was successfully evaluated by a diffusion equation derived from the observation of the weight gains due to the incorporation of oxygen. The activation energy for the mobility of oxygen in the oxygen-deficient perovskite- type structure was obtained to be 6∼8 kcal/mole. The energy required for the structural change from the brownmillerite-type phase to the cubic perovskite-type one was estimated to be 43 kcal/mol which decreased with the increasing M content.

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In order to elucidate the catalytic action of fatty acids on the autoxidation of cyclohexane, the autoxidation of cyclohexane and the decomposition of cyclohexyl hydroperoxide (CHP), which was regarded as an intermediate of the autoxidation, were studied in the presence of various fatty acids such as acetic [1], propionic [2], caproic [3], monochloroacetic [4], and dichloroacetic [5] acids.
It was found that the addition of the fatty acids caused the considerable effects on the cornposition of the expected products(cyclohexanol+cyclohexanone), as well as an acceleration of the rates of both the oxidation of cyclohexane and the decomposition of CHP as described below.
The decomposition rate of CHP was first-order and zero-order with respect to the concentrations of CHP and acid, respectively.
The decomposition rate constants of CHP at 130°C in n-dodecane containing 3.8 mol% fatty acid at the initial CHP concentration of 0.02 mol/l were 5.98×10^-3 for [1], 8.61 × 10^-3 for [2], 7.51×10^-3 for [3], 35.4×10^-3 for [4] and 38.4 × 10^-3 min^-1 for [5]. Furthermore, the activation energy for the decomposition in the presence of acetic acid at 130∼170°C was 17.9 kcal per mole. The main products of the decomposition were the acid esters of cyclohexanol and cyclohexanone, and the yields of the products after saponification of the decomposition products were 82.3, 79.9, 80.3, 68.9 and 59.1 mol% for [1], [2], [3], [4] and [5], respectively. The order of these values were approximately in the inverse order of the acidic strengths which were related to the above decomposition rate constants. A similar tendency in the yields was observed in the autoxidation of cyclohexane.
From the above results, it was presumed on the autoxidation of cyclohexane in the presence of fatty acid that the decomposition of CHP by the ionic mechanism to the formation of the desired products takes place predominantly.

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The effect of temperature, dose-rate and various additives such as acetone, nitrate ion, nitrous oxide and water have been studied in γ-radiolysis of liquid ammonia. Up to doses of about 10¹⁹eV/g almost dose-independent G-values of 0.12 for N₂H₄, 0.82 for H₂ and 0.21 for N₂ were obtained at 30°C.
The N₂H₄ concentration at the steady-state was 5.6 × 10^-7 mol/NH₃ mol for doses greater than 8 × 10¹⁹eV/g, where G-values of H₂ and N₂ increased to 0.84 and 0.27, respectively. The stationary N₂H₄ concentration showed a significant increase upon lowering the irradiation temperature in the case of liquid phase. In solid phase, at -196°C, G-values were 0.08, 0.2 and 0.04 for N₂H₄, H₂ and N₂, respectively.
The rate of formation of N₂H₄ depended on dose-rate at relatively high dose. The presence of nitrous oxide, a typical electron scavenger in aqueous solutions, led to a decrease in the N₂H₄-yield. On the other hand, a maximum yield of N₂H₄ was obtained at the concentration of about 50 mol % NH₃ in an aqueous solution at the irradiation temperature of 30°C.

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The catalytic cracking of various aliphatic sulfides on the silica-alumina catalyst by the use of a pulse reactor was investigated. The cracking reactivity of these sulfides increased in the following order.
CH₃SCH₃<C₂H₅SC₂H₅<C₃H₇SC₃H₇<n-C₄H₉SC₄H₉ This order is in accordance with that of the electron donability of alkyl group adjacent to sulfur atom in the sulfide molecule, because a linear relationship was observed between the logarithms of the apparent first order rate constants of this reaction and the Taft σ which is the measure of the electron donability of alkyl group in the molecule.
On the other hand, the cracking activity of the silica-alumina catalyst decreased when the effective acid sites on the catalyst surface were poisoned by treating it with KOH solution in the range of 0 to 0.14 meq/g. However, the observed apparent activation energy did not change by this treatment. Aliphatic sulfides were also decomposed in the presence of solid phosphoric acid catalyst having predominantly Brönsted acid sites and the order of the cracking reactivity was nearly similar to silica-alumina.
From these results, it was concluded that the cracking of aliphatic sulfides on silica-alumina catalyst proceeds on the Brönsted acid sites.

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Silica xerogel is used as a support of metal catalysts. This paper deals with the relation between the physical structure and the supporting effect of the silica xerogel on the dispersibility and the heat resistivity of the supported palladium particles. It was found that specific area of metallic palladium (a measure of dispersibility) was a function of the micropores and the rate of sintering of palladium particles (a measure of heat resistivity) was proportional to the mean radius of the micropores. Consequently, it may be concluded that the mean radius of the support may play an important role in the dispersibility and heat resistivity of palladium particles.

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"Silicagel" has been usually aged in alkaline solution such as caustic ammonia, because it was considered to be an acidic substance. However, it has recently been recognized that silicagel was a kind of amphoteric substance. In this report, it was examined whether silicahydrogel could be aged in an acidic solution such as sulfuric acid solution, and what kind of xerogel were obtained from the hydrogel. Specific surface areas of the aged silica xerogel in sulfuric acid decreased to a half of that of the unaged one, while the total volume and the mean radius of micropores increased proportionally to the increase of concentration of sulfuric acid. The physical structure of silica xerogel aged in an acidic solution was shown to be ap- preciably different from that of silicagel aged in an alkaline solution.

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Co-oxidation of cyclohexane with acetaldehyde in the presence of cobaltous acetylacetonate catalyst has been investigated in benzene at 40∼70°C. In the absence of the aldehyde, cyclohexane is not oxidized, but in its presence in high selectivity (95 %), forming cyclohexanol, cyclohexanone and e-caprolactone. The mechanism of this reaction is different from the reported mechanism of the oxidation of the neat cyclohexane. In co-oxidation, cyclohexane is oxidized consecutively (cyclohexane → cyclohexanol → cyclohexanone → ε-caprolactone). In the absence of the catalyst, (I) and (II) proceeded by the reactions of cyclohexane and cyclohexanol with acylperoxy radical which is formed in the autoxidation of aldehyde. The step (III) is the reaction of cyclohexanone with peracetic acid (Baeyer Villiger reaction). With cobalt catalyst, (I) and (II) seem to proceed also by the reaction with acyloxy radical or acylperoxy radical which is produced by the decomposition of peracetic acid.

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CH₃CF₃ a by-product of the process preparing CH₂=CF₂ from CH₃CCl₃ or CH₂=CCl₂, is fairly stable and not easily dehydrofluorinated by pyrolysis. The objects of this paper are to find effective metal fluoride catalysts, and to elcidate their activities for dehydrofluorination.
Experiment has been carried out by a flow reactor in the absence or presence of various metal fluorides, and the acidities of these fluorides has been determined by the normal butyl amine titration method.
The results obtained are as follows:
1) The dehydrofluorination in the absence of catalyst at temperatures higher than 750°C is of the first order kinetics and the reaction rate constant k is given by
k =1.63 × 10¹⁰ exp (-53800/RT)
2) As in the dehydrofluorination of CH₃CHF₂ which was reported by us previously, (synthesized) AlF₃, FeF₃, MgF₂ are acive for dehydrifluorination at lower temperature as 530°C, while (commercial) AlF₃, CaF₂, SrF₂, BaF₂, ZnF₂, CdF₂, MnF₂, SnF₂ are inactive. All the catalytically active fluorides have some acidity, while inactive fluorides have none, and hence the acidity appears to be oirrelated with the catalytical activity.
3) Basic aluminum fluoride has been found active and the most stable. The dehydrofluorination reaction catalyzed by this catalyst has been proved to be surface reaction controlling, and the activation energy is 28.3 kcal/mol.

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The Pd(II)-Cu(II)-Y zeolite catalyst was prepared by two-step ion exchange of Na⁺; in the first place with Pd(NH₃)₄Cl₂ aqueous solution, and in the second with CuCl₂ aqueous solution. Vapor phase oxidation of propylene in the presence of steam over the catalyst in the temperature range of 100∼150°C at atmospheric pressure gives acetone with good yield comparable to the homogeneous catalytic systems. Selectivity of acetone formation was higher than 80 %. By-products were carbon dioxide, acetaldehyde, propionaldehyde and trace amount of acids. These results suggested that electron transfer occurred from Pd(0) to Cu(II) existing in the definite sites of the zeolite structure. The catalyst deactivation by ammonia addition and the low catalytic activity of the Pd(NH₃)₄(II)-Cu(NH₃)₆(II)-Y zeolite catalyst suggested that the active species were the partially aquated Pd(II), and Cu(II) ions.

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New photosensitive polymers which have high sensitivities and low softening temperatures were prepared by the condensation reactions of poly(2-hydroxyethyl acrylate)(PHEA), poly(2- hydroxypropkyl acrylate)(PHPA) and 2-hydroxyethyl acrylate-vinyl acetate copolymer(PHEAVAc) with cinnamoyl chloride.
Polymerization of 2-hydroxyethyl acrylate could be conducted in water or in aprotic polar solvents such as hexamethyl phosphoramide(HMPA). The condensation reaction of PHEA with cinnamoyl chloride proceeded easily in HMPA and the reaction product was soluble in organic solvents such as toluene and ethyl methyl ketone, but the product obtained by the Schotten-Baumann reaction changed to an insoluble material after drying. This might be attributable to an intermolecular transesterification of PHEA occured as a side reaction. Polymerization of 2-hydroxypropyl acrylate and copolymerization of 2-hydroxyethyl acrylate and vinyl acetate were conducted in HMPA and the condensation reactions of the polymers thus obtained with cinnamoyl chloride were carried out in HMPA.
The photosensitivities of these polymers containing 5 wt % of 5-nitroacenaphthene as sensitizer were found to be ca.2∼8 times higher than that of KPR, which is a commercially available photosensitive resin made from polyvinyl cinnamate.
The softening temperatures of the polymers were 45∼60°C and were lower than that of polyvinyl cinnamate(107°C).

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Electrical conductivities, absorption spectra and thermally stimulated current of single crystals of potassium dichromate were measured to make clear its electrical and optical properties. The activation energy of ionic conduction was found to be 1.21 eV along the perpendicular axis to (113) plane.
The fundamental absorption edge of a potassium dichromate crystal along the perpendicular axis to (120) plane was 2.16 eV at 293°K. Further, it was found that the absorption edge shifted to shorter wavelength, as the temperature decreased.
It was detected by the measurements of thermally stimulated current that the carrier traps were located at 0.46 eV and 0.50 eV below the conduction band along the perpendicular axis to (113) plane. These traps may be anisotropic, since the thermally stimulated current along the perpendicular axis to (120) plane was only slightly observed.

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This paper deals with the electrodeposition of nickel from Ni(CF₃COO)₂-HCONH₂ solutions. The properties of Ni(CF₃COO)₂-HCONH₂ bath and the mechanism of electrodeposition of nickel were studied.
Specific conductance of a Ni(CF₃COO)₂-HCONH₂ solution and apparent molecular volume of Ni(CF₃COO)₂-HCONH₂ became constant when the concentration of Ni(CF₃COO)₂ was increased beyond about 200g/l.
There was a tendency for Ni(CF₃COO)₂-HCONH₂ solution to increase its viscosity with the increase of the concentration of Ni(CF₃COO)₂.
Bright and smooth nickel deposits were obtained at a current density in the range of 0.5∼2.0 A/dm² from Ni(CF₃COO)₂ 80∼100 g/HCONH₂ 11 bath at 60°C, the current efficiencies for cathode and anode being about 90 % and 100 %, respectively.
The cross-section of the nickel deposits was found to have granular structure. The grain orientation was strong [111], but weak [220] and [200]. The grain size was 70∼80 Å.
The rate of electrodeposition of nickel from Ni(CF₃COO)₂-HCONH₂ bath at a current density ranging from 0.9 to 4.8 A/dm² was controlled by a charge transfer reaction.

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Infrared spectra were measured for the synthetic pyralspite garnets [Mg₃Al₂Si₃O₁₂(Py), Mn₃Al₂Si₃O₁₂(Sp)] and the ugrandite garnets [Ca₃.Al₂Si₃O₁₂(Gr), Ca₃Fe₂AlSi₃O₁₂(GA), Ca₃Fe₂Si₃O₁₂(An), Ca₃Cr₂Si₃O₁₂(Uv)] Four bands(A-D) were observed for Py and Sp in the range of 1000∼800 cm^-1, in which three of them, B, C, arid P were assigned as the split of stretching vibration, v_s, of SiO₄ tetra hedron. However, two bands for Gr and GA and three bands for An and Uv were observed in the same range (Table 2 and Fig.1), although four bands were always observed for the natural garnets.
The site group splitting of SiO₄ tetrahedron was defined as
Δv_s= B-(C+D)/2
It has been known that the distortion of SiO4 tetrahedron in pyralspite garnets was greater than that in ugrandite garnets (Fig.2). The tetrahedral edge distortion was defined as δ_t= d_u-d_s/d_u×100, where d_e is the length of shared edge between SiO₄ tetrahedron and dodecahedron, d_u is the length of unshared edge of SiO₄ tetrahedron. It was shown that the smaller the tetrahedral distortion the smaller became the site group splitting (Fig.3).
The frequencies of IR bands (A-G) which might relate to SiO₄ tetrahedron decreased with increasing lattice constant, and ionic radii of dodecahedral and/or octahedral cations(Fig.4 and 5). IR bands related to octahedral cations (H and I) were observed in the following ranges, AlO₆: 480∼450 cm^-1, FeO₆: 430∼380 cm^-1 and CrO₆: 450∼410 cm^-1. The difference of the amounts of octahedral distortion did not appear explicitly in the octahedral IR band splitting because the octahedral distortion was considered to be less than SiO₄ tetrahedral one in the garnet structure.

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Emerald single crystals have been grown by a molten V₂O₂ flux technique. V₂O₂ and natural beryl crystal mixture at the ratio 4 : 1 (wt %), containing 5.0 wt. % Cr₂O₃, were charged in platinum crucible. Soaking temperature was about 1050°C and natural beryl was used for seed.
Synthetic emeralds were examined by the microscopic observation, Laue photograph, infrared spectrometry, etc.
It is found that the condition with the nutrient temperature being higher than that of natural beryl seed and an use of buffle plate proved an excellent for the emerald growth. Without an use of buffle plate, a large number of small emerald single crystals, having hexagonalcolumnar habits, were grown near liquid surface.
A solubility curve of the synthetic emerald in V₂O₂ flux were examined and found that about 6.3 g of synthetic emerald was melt in V₂O₂ at 1050°C. Laue photographs of both c and m planes of synthetic emeralds were identical with that of natural beryl, and showed good crystallinities.
Infrared spectra of synthetic emeralds were recorded from 400 to 4000 cm^-1 on powder samples using a KBr wafer technique. Band with maxima at 490, 520, 590, 648, 679, 738, 802, 955, 1015, 1200±5cm^-1 were observed and were in essential agreement with the literature values for beryl.
The 3, 500 cm-' broad band might be attributed to water molecules picked up by the KBr during sample preparat ion.
During crystal growth of emerald, card-like hexagonal tabular steps were observed on c-plane, the thickness being about several ten microns.

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Department ofApplied Chemistry, Faculty of Engineering, Kyushu University Hakozaki, Fukuoka-shi, Japan Dehydration phenomena observed in four crystalline hydrates were investigated by means of polarization microscope using thin single crystal specimens. Dehydration were observed from CuSO, 5 H₂O to tri-hydrate, similarly, Na₂CO₃ 10 H₂O ---+- hepta-hydrate, H₂C_2CO^2-2 H₂O anhydrate, and Na₂13407 10 H₂0--di-hydrate. In the former three cases, dehydration extended from a few original points isotropically to the single crystal plates, while an apparent anisotropy was observed in the last case.
Further measurement of the anisotropy in the dehydration of Na₂1340710 H₂O, using specimens having various orientations, revealed the anisotropy to be most marked in the (100) plane, and the dehydration to proceed preferentially along 001 direction. This direction coincides with that of {Na(H₂0)4} chains in the crystal structure of Na₂13, 07.10 H₂O, and, therefore, it is considered that the existence of such a chain structure may bring about the anisotropy in its dehydration.

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In aqueous solutions, manganese (III) ion in ethylenediaminetetraacetatomanganate (III) complex (Mn(I)CEDTA) is reduced to manganese(III) ion, so that at least a part of the ligand EDTA is expected to be converted into some fragmental species. This paper deals with the chemical formula of the species which are formed by this decomposition. This decomposition reaction involves the decarboxylation from EDTA ligand, and therefore, the charge of fragmental species must be changed. This difference in charge is very useful for the separation of the fragmental species. The methods of separation are as follows:
After the completion of the decomposition reaction, cobalt(II) acetate and hydrogen peroxide were added to the solution, and air was passed through the solution to form substitution-inert Co(III) complexes which coordinate with the fragmental species of the decomposition. products. The cobalt(EI) complexes thus obtained were separated by ion-exchange chromatographic technique to an anionic, a cationic and a non-charged part. From the anionic and the cationic part crystals were obtained and identified by elemental analysis and IR spectra. Products in the noncharged part were identified by visible spectrum and ion-exchange chromatographic behavior. These results are listed in Fig.1, Fig.3, Table 1 and Fig.4 respectively. By this procedure, the formations of ethylenediaminetetraacetatocobaltate(M) (CoOVEDTA), ethylenediaMinetriace- tatocobaltOn (CoMEDTRA) and ethylenediaminediacetatocobalt(1g) (Co(Iii)EDDA) complexes were confirmed.
From these results, it was concluded that decomposition products of Mn(III)EDTA complex in aqueous solutions contained EDTRA and EDDA. In addition to these, it was found that unchanged EDTA still remained even after the completion of the reduction of manganese(ll) to manganese(I1) in Mn0(11)EDTA complex. The amount of unchanged EDTA was determined as a function of pH, as given in Table 2.

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On bombardment of natural chromium with a particles up to 44 MeV, ⁵²Fe, the intended nuclide of this study, and other nuclides were formed and they were throughly examined. The stacked foils of electrolytically deposited chromium metal were used for bombardment. The excitation curves and thick target yields curves of these nuclides were determined from the results of activity measurements. It was found that ⁵²Fe was mainly formed by (α, 2 n) reaction of ⁵⁰Cr and the excitation curve for this reaction showed maximum cross section of 1 mb when the energy of a particles was 31 MeV. ⁵⁵Fe, byproduced nuclide, being not chemically separated from ⁵²Fe, was formed by (α, n) and (α, 2 n) reactions of ⁵²Cr and ⁵³Cr, respectively. The maximum cross section was found 225 mb when the energy of α particles was 15 MeV.
From the thick target yields curves, it was found that the total amounts of ⁵²Fe produced were 3.8 and 8.2, μCi/μAhr but the ratios of activities ⁵⁵Fe to ⁵²Fe were 11.3 and 6.3 % for 30 and 40 MeV of a particles, respectively. The total activities of byproduced nuclides amounted to about 1 mCi/μAhr for the latter case, but these nuclides could easily be separated from ⁵²Fe with quite high yield by the proposed radiochemical method.
For the production of ⁵²Fe completely free from ⁵²Fe, it requires to use an enriched ⁵⁰Cr target, but it has several disadvantages such as high cost and tedious procedure for recovery of ⁵⁰Cr for reuse.
It may be said that as a conclusion a bombardment on natural chromium produced ⁵⁴Mn with reasonably high yield and was superior to the sHe bombardment on natural chromium. The amounts of ⁵⁴Mn and ⁵²Mn obtained by this method were six and seventh times, respectively, as much as those obtained by ³He method.

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It is well known that an anion which forms an insoluble salt with mercurous ion accelerates the anodic dissolution of mercury. Tungstate ion in neutral and slightly acidified potassium nitrate media produces a three-step anodic wave. A study of the characteristic of the anodic waves, the first (I) and the second (II), has revealed the following peculiarities: 1) The limiting current shows the remarkable abrupt rise. A change of 30 mV results for the limiting current to become fully developed.2) The addition of tungstate ion shifts the starting potential of the wave (I) and (II) to less positive value but does not change the limiting currents.3) The temperature coefficient of the height of the wave is relatively small for the wave (I) compared to a diffuMon controlled limiting current.4) The limiting current is proportional to the corrected pressure of mercury, h_corr. and the i_corr.t_d value remains constant at 1.41±0.02 μC for the wave (I) and 6.03±0.07μC for the wave (II). Therefore, by assuming the formation of a mono-molecular film of Hg₂WO₄, the area per molecule is calculated to be 69.6 Ų for the wave (I) and 18.3 Ų for the wave (II) respectively.5) Electrocapillary curves, measured by the droptime method, show that a remarkable change in the interfacial tention occurs in the potential range of the limiting current of the wave (I).
From the results above, it is concluded that the first and the second waves are caused by the oxidation of mercury to produce a thin film of very insoluble mercurous tungstate. Though mono-molecular in thickness, these films are so cohesive that they prevent the oxidation of mercury. Therefore, the second wave shifts to more positive than the first by 140 mV and the third more positive than the second by 120 mV. As the third wave appeares just before the appearance of dissolution wave of mercury, it is difficult to elucidate the electrode reaction but it seems to be not diffusion but kinetically controlled wave.

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The polarographic behavior of oxalate ion, which forms an insoluble salt with mercurous ion has been studied in neutral and acidified potassium nitrate and acetate buffer solutions. In neutral and slightly acidified solution, oxalate ion produces a three-step anodic wave. The first (I) and the second (II) are attributed to the phenomenon that a mono-molecular film of mercurous oxalate are formed by the oxidation of mercury. Peculiarities of the anodic wave are as follows: 1) The limiting current rises with the remarkable abruptness. Changes of 6 mV for the wave (I) and 7 mV for the wave (II) are resulted for the limiting currents to become fully developed.2) The addition of oxalate ion shifts the starting potential of the waves (I) and (II) to less positive value but does not change the limiting currents.3) The temperature coefficients of the height of the waves (I) and (II) are relatively small.4) The limiting current is proportional to the corrected pressure of mercury, and the i_corr. t_d, value remains constant at 1.36 ± 0.03 μC for the wave (I) and 3.21 ± 0.07 μC for the wave (II). Therefore, by assuming the formation of a monomolecular film of Hg₂(COO)₂, the area per molecule is calcu- lated to be 68.6 Ų for the wave (II) and 28.8 Ų for the (II) respectively.5) Electrocapillary curves show that a remarkable change in the interfacial tention occurs in the potential range of the limiting current of the wave (I).
From the results above, it is concluded that they are both absorption waves. As the third wave appears just before the appearance of dissolution wave of mercury, it is difficult to elucidate the electrode reaction.
The anodic wave of oxalate ion is remarkably affected by the addition of small amounts of halogen ions. The first wave shifts to more negative potential and a new maximum appears just after the second wave. The height of the maximum is proportional to the halogen ion concentration. Therefore, the method is found to be suitable for the determination of halogen ion at the concentration range of 10^-5 mol/l.

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The thermal decomposition of mono-, di-, and tribromobenzenes at 650∼850°C has been studied by gas chromatography. At lower temperature (700°C), each sample showed chracteristic pyrolysis pattern. It was revealed that each pyrogram was composed of peaks due to bromobenzenes different from, starting one. This change in number of bromine in resultant molecules would be attributed to the dehalogenation and substitution reactions which occurred in a decomposition tube.
Nucleophilic behavior of bromine produced in dehalogenation reaction was studied by a comparative examination of the decomposition products with the reaction-index calculated by a MO (Huckel approximation) method.
At higher temperatures (800°C), similar pyrograms were obtained irrespective of structural isomerism of starting bromobenzenes. This colligative properties of thermal decomposition phenomena would be resulted from the random substitution process.

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On the basis of the NMR spectra of ion-exchange resin swollen in aliphatic alcohols, a degree of dissociation of sulphonated resin in the H-form, swelling, and a motion of alcohols inside the resin were investigated. The shift of the peak due to OH proton of alcohol inside the resin depended upon the hydrogen ion molalities and alcohol contents of swollen resins. The chemical shifts of OH protons of alcohols inside and outside the resin were shown to be related uniquely to the mole fraction of protons in alkoxonium ions(ROH₂⁺). The degree of dissociation of H-form resin, Dowex 50 W, was estimated and, concerning with the solvent, it followed the following sequence: water>methanol>n-propanol. From the measurements of width of the peak due to OH protons of alcohols inside and outside the resin, it was presumed that the susceptibility of the resin was about -0.80 × 10^-6, and that when the contents of alcohol per mole of exchanged group were less than 4 moles, the motion of alcohol molecules in the resin was markedly restricted.

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The photochemical reaction of 4-nitropyridine in the hydrochloric acid-2-propanol solutions has been investigated under the atmosphere of oxygen. Photolysis of the 2 × 10^-3, 2 × 10^-2, and 1 × 10^-1 mol/l solutions of 4-nitropyridine gave 4-hydroxypyridine, N, O-di 4-pyridyphydroxylamine, and 4-hydroxylaminopyridine, respectively. By means of UV spectroscopy, it was found that N, O-di 4-pyridyphydroxylamine was formed in the dark by the condensation reaction of 4-hydroxylaminopyridine hydrochloride with 4-hydroxylaminopyridine, both of which were formed photochemically. The result of the quenching study and of the value of the intersystem crossing coefficiency of 4-nitropyridine hydrochloride suggested that the photochemical reaction which produced 4-hydroxypyridine proceeded via the triplet state of 4-nitropyridine hydrochloride. The nitrite and nitrate produced by the photolysis of 4-nitropyridine were assumed as the intermediates of the 4-hydroxypyridine formation.

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Oligomerizations of isoprene with the catalysts consisting of CoCl₂, NaBH_{4 and} Ph₃P in ethanol were investigated in detail.
A new 1, 3-coupled dimer of isoprene, 2, 3, 5-trimethyl-1, 4, 6-heptatriene [1], was mainly obtained when the molar ratio of Ph₃P to CoCl₂ was smaller than 1 (Table 1). But the two linear 4, 4- and 1, 4-coupled dimers, 2, 7-dimethyl-1, trans-3, 7-octatriene [3] and 2, 6-dimethyl-1, trans-3, 6-octatriene [4], were obtained when the molar ratio was larger than 1 (Table 2).
In both cases, some linear 1, 4- and 4, 4-coupled dimers, dimethyloctadienes, were also obtained. In these oligomerizations, in place of Ph₃P other trialkylphosphines (tri-n-butylphosphine and diethylphenylphosphine) and ditertiaryphosphine (bis-diphenylphosphinoethane) were studied as the ligands (Table 3 and 4). Furthermore, the solvent effect was also observed, that is, the cyclic dimers, 2, 4-dimethyl-4-vinyl-1-cyclohexene and dipentene (and/or diprene) were obtained by the use of the aprotic solvent such as toluene (Table 5).

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The reactions of propylene oxide with Grignard reagents (RMgX) in various ethers have been tested. Relations between the reaction conditions and compositions of obtained four alcohols (CH₃CH(R)CH₂OH, CH₃CH(OH)CH₂R, CH₃CH₂CH(R)OH and CH₃C(R)(OH)CH₃) were investi- gated, and the reaction mechanism was also studied. The Grignard reagents were prepared from ethyl bromide, ethyl iodide, isopropyl bromide, isopropyl iodide and bromobenzene; and diethylene glycol dimethyl ether, tetrahydrofuran, ether, n-butyl ether and anisole were used as solvents.
The proportions of propylene oxide to Grignard reagent did not show any influence on the distribution of alcohols, while they affected the ratio of alcohols to halohydrins. Yields of halohydrin increased with increasing ratio of Grignard reagent to propylene oxide. Organic groups in Grignard reagents did not affect the proportion of four kinds of alcohols, but with regard to halogens in the Grignard reagents, the steric factor affected the compositions of two kinds of halohydrin (CH₃CH(X)CH₂OH and CH₃CH(OH)CH₂X). As a significant difference in the compositions of alcohol was observed between ether and tetrahydrofuran (solvents), product distributions against the reaction time were investigated in the reactions between propylene oxide and halohydrins in both solvents. Finally, possible two courses for the formation of alcohols were infered. The Grignard reactions of aldehyde or ketone were investigated to confirm the proposed mechanism.

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In connection with the synthesis of disperse dyes and pigments, the contribution of annellation in the thermal stability of some colouring matters have been studied.
Benzimidazole, phthaloperinone, 3'-hydroxyquinophthalone, quinazolone-phthalone and their annellation derivatives were prepared by the reaction of substituted phthalic or 2, 3-naphthalenedicarboxylic anhydride with o-phenylenediamine, 1, 8-diaminonaphthalene, 3-hydroxy-4-carboxyquinaldine or 2-methyl-4-quinazolone. The fastness to sublimation for these compounds on polyester fibre and to migration on polyvinylchloride sheet, and the thermal behavior by thermal gravimetric analysis (TGA) were tested. The thermal stabilities for the annellation derivatives prepared from 2, 3-naphthalenedicarboxylic anhydride are excellent in comparison with those for the derivatives from phthalic anhydride. These facts remarkably suggest annellation effect to the thermal stabilities of colouring matters. Further, an annellation effect to colour and lightfastness of these colouring matters also were discussed.

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Reaction condition of monosulfonation of Cu-phthalocyanine (Cu-Pc) with fuming sulfuric acid and purification methods of the products were studied. When the reaction of Cu-Pc with 30% fuming sulfuric acid was carried out at 15±1°C, the monosulfonate was obtained in fairly good yield. It was found that the products can be separated by means of salting out method or by the use of adsorption chromatography on silica gel when the yield of the monosulfonate was relatively high and electrophoresis on cellulose acetate membrane was usefull for the quanti- tative analysis and the structure of monosulfonate was determined.

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Aliphatic polyrhodanines were prepared by the polycondensation reaction of bisrhodanines with dialdehydes terephthalaldehyde(TPA), glutaraldehyde(GA), and glyoxal(GO)(Table 5). The bisrhodanines(ethylene bisrhodanine(EBR), trimethylene bisrhodanine(TBR), hexamethylene hisrhodanine(HBR), decamethylene bisrhodanine(DBR), and dodecamethylene bisrhodanine(DoBR)) were synthesized from the corresponding diamines via dithiocarbamate (Tables 1 and 2).
The infrared and ultraviolet absorption spectra of the polymers were measured to confirm their proposal structures. Elementary analysis agreed with the values calculated for the aliphatic polyrhodanine (Table 6). The reduced viscosities of the obtained polymers were 0.05∼0.35 in concentrated sulfuric acid (Tables 3 and 4).
In a series of aliphatic polyrhodanines prepared from bisrhodanine with TPA, the electrical resistivity and its activation energy(E_a) increased with increasing the number of methylene chain. The values of E_a(eV) were 0.9₄ for EBR-TPA, 1.3₅ for TBR-TPA, 1.8, for FIBR-TPA, 2.2₅ for DBR-TPA, and 2.3₆ for DoBR-TPA (Fig.2 and 3). For the aliphatic polyrhodanines, EBR-GO and EBR-GA, their electrical conductivity above their softening temperature were found to be higher than the values measured at low temperature occurred the drastic change of conductivity coincides with the temperature appeared the weight loss by thermogravimetric analysis about 135°C for EBR-GA, and about 148°C for EBR-GO.

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The effect of bis(2-chloro-l-methyl)ethypether (CIPE) on the cationic polymerization of styrene initiated by antimony pentachloride (SbCl₅) was studied in cyclohexane solution. The poly- merization degree was increased by the addition of small. amount of CIPE, whereas the rate of polymerization was decreased with increasing of CIPE. The overall activation energy was 7.7 kcal/mol.
CIPE forms a stable complex with SbCl₅, which may be dissociated on heating to chloroisopropyl carbonium cation. This carbonium cation is capable of initiating the cationic polymerization of styrene. But the oxonium anion (ClCH₂CH(CH₃)O-SbCl₅) may be more stable than carbonium cation. Therefore the high molecular weight polystyrene (MW=180000) was obtained.

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The effects of polymerization conditions were investigated on the graft copolymerization of methyl methacrylate (MMA) initiated by ceric ammonium nitrate on starch and triethylamino starch (TEAS) in aqueous medja.
Under the conditions such as starch or TEAS concentration of 2 %, HNO₃ concentration of 0.014 N, polymerization temperature of 50°C and reaction time of 2 hrs., the total conversion (T), the percentage of grafting (P) and the graft efficiency (E) became higher with increasing initiator concentration and lower with increasing monomer concentration (4∼17 %).
The polymerization temperature (30∼60°C) appeared to be most suitable at 50°C from the results of (P). On the polymerization time, (T) and (P) became higher with increasing the time. (P) and (E) showed maximum values at some concentration of starch or TEAS respectively, and similarly with HNO₃ concentration also. The value of (P) became larger at the region of high HNO₃ concentration with low concentration of initiator, whereas in the case of low concentration of HNO₃ with high concentration of initiator.
(P) and (E) of the aqueous suspension system of starch or TEAS were generally higher than that of the aqueous solution system, and the results of the starch system were larger than that of the TEAS system.
The graft copolymer was quite insoluble in boiling water, methanol and acetone, but dissolved in dimethylsulfoxide. Therefore, the cross-linked structure seemes to be absent in this copolymer.

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The polymerization of vinyl acetate with trapped radicals in various organic solids, especially lauTic acid, irradiated with ⁶⁰Co γ-rays, was investigated. It was observed that vinyl acetate is polymerized with various irradiated organic solids but its rate of polymerization is low. As one of the cause of this low yield, the recombination of radicals, formed by the dissolution of irradiated organic solids in monomer solutions, may be considered.
In the polymerization of vinyl acetate with pre-irradiated lauric acid at 20° C, the yield of poly (vinyl acetate) was maximum when methanol content in monomer solution used to control solubility of lauric acid was 7.7 percent and when prerradiation dose on lauric acid was 2∼4 MR.
The effect of polymerization temperature on the yield of poly (vinyl acetate) is important. At low temperature, the polymerization of vinyl acetate appeared to be mainly induced by trapped radicals but in the case of polymerization at 60° C, it seemed to be initiated by decomposition of peroxide produced with irradiation.

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The study of the oxidation of propylene in liquid phase based on Hochst-Wacker process was carried out experimentally in packed columns.
The capacity coefficients for chemical absorption in packed columns, calculated by the reaction factor-matching method using the chemical absortion data obtained in an agitated vessel, were in good ageement with those obtained experimentally.
It was found that this reaction could be treated as chemical absorption accompanied by simultaneous reversible pseudo-first order reaction and that the chemical absorption rates in packed columns could be estimated by the reaction factor-matching method using the data obtained in an agitated vessel.

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Plate efficiency of a distillation column was calculated by taking into account the vapor concentration distribution in the plate spacing.
Generally, although it has been assumed that the vapor in the plate spacing has been completely mixed (being uniform vertically toward vapor-flow direction), actually, the vapor phase in the column has not been completely mixed.
This paper deals with the mixing effects on the plate efficiency, EMV, based on the dispersion model:
This equation indicates that the larger the Fern, the smaller is the Emv and its effect incieases with increasing PeL and EOG.
But it is very much small under the usual operating condition.

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The ultra-fine ferric oxides of 50 to 650 Å in diameter were examined by X-ray diffraction, differential thermal analysis, electron microscope and H₂O adsorption in order to find the cor- relation of the ultimate and agglomerated structures of the ferric oxides with the heat of im- mersion in water, ΔH_I.
It was shown that ΔH_I is almost independent of the particle size, except B-500-1 and B500-2, samples which showed higher ΔH_I values (Fig.2). These two samples were prepared by heating amorphous hydrous oxide at 500&deg; C, and showed partial crystallization to α-Fe₂O₃ and considerable sintering. Higher ΔH_I values of the sintered samples were interpreted by the' presence of interparticle micropores, through which H₂O molecules are more easily permeable than N2 molecules. The surface activity incident to the structural change is also thought to be pertinent to the higher ΔH_I.

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The catalytic activities of MgO-Al₂O₃ with various compositions for the title reactions have been examined. The MgO-Al₂O₃ of molar ratio 20 showed a maximum activity for the decomposition of diacetone alcohol when calcined at 400° C, the activity being greater than that of MgO. The activity was found to correlate with the basicity of the catalysts. The activity for the alkylation of phenol increased with increase of the MgO content, the highest activity being observed for MgO-Al₂O₃ of molar ratio 20 where the yield of o-cresol was 66 %. The activity was entirely different from that of MgO or Al₂O₃. The basicity of MgO-Al₂O₃ cor- related with the activity, but not with the selectivity.

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Orientation in the Friedel-Crafts acylation of 3-methoxydiphenylene oxide [1] was studied. The reaction of I with acetyl chloride in the presence of aluminium chloride in nitrobenzene was carried out at 20° C for 1 hr, 2-acetyl-3-methoxydiphenylene oxide was obtained in 86 % yield. The site of acylation of I was elucidated. Similarly, the reaction with benzoyl chloride, 2-benzoyl-3-methoxydiphenylene oxide was obtained in 90 % yield.

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The ring-opening of trans-4-methoxystilbene oxide [1] with benzoic acid in chloroform gave a monobenzoate [2], which was converted to ketobenzoate [3]. The structure of [3] was determined by comparision with authentic ketobenzoates. The result revealed the doubtful mechanism of double inversion mechanism involved in the ring opening of [1].

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It has been reported by Cainelli that the reaction of benzaldehyde with methylene iodide and the amalgam of magnesium with mercury affords styrene. When a small amount of mercury was used for this reaction, the yield of styrene was remarkably increased (Fig.1). According to this method, following aldehydes and ketones gave the corresponding carbonyl-methylenated products in the yields given in the parentheses: p-methylbenzaldehyde (75 %), p-chlorobenzaldehyde (67 %), n-heptaldehyde (48 %), diethyl ketone (68 %), cyclohexanone (38 %).

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It was found that a metal powder alone can initiate telomerization reaction. The telomerization reaction of ethylene with carbon tetrachloride under ethylene pressures by batchwise system initiated by metal zinc powder were studied.
In this catalyst system, the reaction rate based on the concentration change of carbon tetrachloride was obtained larger than that in a system with other general radical initiator such as α-α'f azobisisobutyronitrile.
When solvents were used the extent of conversion of carbon tetrachloride and average telomerized degree of telomers were, in general, larger than those with metal zinc alone. The extent of conversion of carbon tetrachloride was about 90 % in the presence of zinc and tertbutanol in a temperature range from 70 to 90deg; C.

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It was found that the metal powder and metal salt catalyst system can initiate the telomerization reaction. The telomerization reaction of ethylene with carbon tetrachloride under ethylene pressures by batchwise system using the catalyst with tin and lithium chloride was studied.
The reaction rate was accelerated by addition of tert-butanol ranging from 5 to 10 vol % of carbon tetrachloride in those catalyst systems. The extent of conversion of carbon tetrachloride were about 80 % under the favorable reaction condition where 5 g/l of tin and 0.5 g/l of lithium chloride were used and the reaction was carried out in a temperature range from 70 to 90deg; C for 4 hours.
The reaction rate by the present catalyst system was larger than that by other general radical initiator such as α-α' azobisisobutyronitrile or benzoyl peroxide and long life of catalytic activity was obtained.

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The bulk investigation on the polymerization of methylmethacrylate (MMA) was carried out by using 2, 2'-azobisisobutyronitrile as initiator. For the termination rate constant (kt), the following equation was obtained.
where kt₀ is the initial kt independent of the viscosity of the polymerizing system, P_n is cumulative number of average degree of polymerization and x is conversion rate. The time-con. - version rate curves and the values of number of average degree of polymerization calculated by the above equation were in good agreement with the experimental results up to 50∼40 % conversion rate.

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