¹³C-NMR spectra of monosubstituted anilines have been measured in 20 mot % DMSO and in methanesulfonic acid. The total electron densities for rn and p-substituted anilines have been obtained by the CNDO/2 MO method.
In m- and p-substituted compounds, changes in ¹³C chemical shifts of the ring carbons by protonation on the amino group are very large the ring carbons to which the amino group is attached show high field shift by about 20 ppm. On the other hand, the carbons at ortho and para positions show downfield shifts by 8-13 ppm and 8-15 ppm, respectively, whereas changes in chemical shifts of the carbons at meta position are extremely small.
The displacements of the chemical shifts for the ring carbons due to t he protonation were found to be well correlated with the differences between the total electron densities obtained for the anilines and the anilinium ions (Table 3, 4 and 5).
These results suggest that, in m- and p-substituted an ilines, the displacements of the shifts are mostly influenced by the electronic effect due to the hybridization from sp² to. sp³ at the amino-nitrogen.

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We constructed a differential flow microcalorimeter designed by Picker et al. in order to measure excess heat capacities of binary mixtures and checked the reproducibility of the calorimeter by using aqueous NaC1 solutions, because Desnoyers suggested it as a standard chemical solution. We obtained the following equation for the apparent molar heat capacity, c_{p, φ}: C_{p, φ} =-82.46+20.59 m^1/2+35.86 m-11.37 m^3/2 This result is a little smaller than that of Picker et al. but the error is believed to be about 1% of 50JK^-1⋅ mol^-1.
Using this calorimeter, we measured excess heat capacities, C_p^E of following binary mixtures:
1) Heptane cyclohexane and + benzene
2) Carbon tetrachloride + benzene and -I toluene In the heptane system, C_p^E is negative but in the carbon tetrachloride system, C_p^E is positive. The experimental results are at variance with the Prigogine-Flory corresponding state theory which predicts C_p^e= 0. It may be explained in terms of the difference in the molecular orientation in pure components and the mixture, which is suggested by Patterson et al.

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In order to get information on structures of the highly concentrated aqueous solutions of non-ionic surface active agents, concentration dependences of gelation, temperature, cloud point, degree of depolarization of scattered light and dissymmetry coefficient of micelles have been investigated at varying temperatures. Non-ionic surface active agents used are poly (oxyethylene) alkyl (C₈ and C₉)phenyl ethers and dodecyl ether. The experimental results showed that 40-70% aqueous solutions of agents were optically anisotropic and formed liquid crystal. The ratio, 1: 1-1√ 3: 1/2, of Bragg's long spacings obtained by small-angle X-ray scattering and the results of polarization microscopic observation revealed that in the region of 40-70% in concentration, middle phase with hexagonal array of cylindrical micelles(negative birefringence) was formed and that lamellar micelles (positive birefringence) were not formed at least up to this concentration. At lower concentration each solution showed negative streaming- birefringence and with increasing concentration its absolute value increases until it decreases after the maximum point. Moreover, as the concentration increases further, streaming- birefringence of the solution was changed from negative to positive values at a definite concentration, which is much lower than 40% depending on nature of the agents. These characteristic phenomena observed in streaming-birefringence are discussed in detail assuming that with increasing concentration polyoxyethylene groups which are situated outside micelles interlink gradually to form network by mediation of water molecules in the solution.

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The rates of the oxidation of sulfur dioxide on several activated carbons treated with various gases such as nitrogen, hydrogen, water vapor and air, respectively, were investigated by means of a TGA apparatus at 100°C in an atmosphere of mixed gases of sulfur dioxide, oxygen, water vapor and nitrogen, whose composition was similar to that of the normal boiler gas.
The rates of the oxidation were expressed by equation ( 1 ) or ( 2 ). The specific activity of the carbon was increased by a treatment with nitrogen or hydrogen at 800°C, while it was decreased by a treatment with air at 350°C. The specific activity of the carbon changed reversibly by the successive treatments with air at 350°C and nitrogen at 800°C. A treatment with water vapor at 800°C had almost no effect on the specific activity although it increased the specific surface area. The results obtained in the effect of surface treatment on the desorption spectrum of the activated carbon revealed that the air treatment at 350°C produced the surface oxides, the oxygen of which was desorbed from the surface at relatively low temperature, and that the fraction of the surface oxygen desorbed as CO₂ was more in the carbon subjected to the air treatment than that subjected to the nitrogen treatment. These results lead to the conclusion that the catalytic activity is closely related to the basic oxide on the carbon surface.

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By the use of an electron microscope the kinetic study on the localized oxide crystal growth, appeared on the surface of iron metal powder (1.3 μ average diameter) by the treatment of it with a mixed gas (80% oxygen and 20% water vapor) at 300-600°C, was carried out.
Two crystals [cylindrical whiskers (CW) and sword-shaped platelets (SP)] grow somewhat uniformly with average lengths of O.45 and 0.8 μ, respectively, and with surface densities of 10⁸-10⁹ cm^-2 at above 400°C. The diameters of CW and the widths of SP vary mainly from 9 to 67 nm and from 20 to 320 nm, respectively, with increasing temperature from 300 to 470°C;. thus, the total amounts of volumetric growths of CW and SP can be determined. T he former decreases rapidly with increasing temperature, whereas the latter remains almost unchanged. As a result, a maximal temperature for the localized crystal growth is about 470°C.
The elongation rates of CW and SP obey the logarithmic rate law after passing a con stant incubation period of 2.5-2.7 min, irrespective of temperature. On the other hand, rates of increase in surface densities show self-accelerating characteristics, whose induction periods of O.1-0.5 hr become longer with a rise in temperature. This induction period is the time required to arrange the incubation process, and the diameters of CW and widths of SP are formed during a constant incubation time at the nucleation sites located in the dislocations within the metal.
All the above kinetic results were found to elucidate the root growth mechanism.

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The mechanism of dehydrogenation of isopentane was studied on active charcoal catalysts impregnated with Cu, Fe or Co. The emphasis was placed on the effect of hydrogen partial pressure in the gas phase on the reaction rate, and the role of hydrogen reverse-spillover on metal-impregnated carbon catalysts.
The rate of the reaction on the metal impregnated active charcoal catalysts decreased with the increase of hydrogen partial pressure without changing selectivities, while the rate on active charcoal without metal was independent of hydrogen partial pressure. The suppressive action of molecular hydrogen on metal impregnated active charcoal catalysts was explained by the potential model of hydrogen fugacity based on the ordinary- and reverse-spillover of hydrogen.
The kinetic study of the reaction suggests that the rate-determining step on the catalysts with a sufficient amount of metal is not the desorption of hydrogen from carbon surface but the abstraction of hydrogen from paraffin by carbon. In this case, hydrogen molecules in the gas phase diffuse onto the carbon through the metal and inhibit the abstraction of hydrogen by carbon. When carbon was impregnated with a small amount of metal, the rate-determing step was thought to be the migration of hydrogen from carbon to metal surface.
The activation energy of hydrogen abstraction from isopentane by carbo n was evaluated to be 6.4 kcal⋅mol^-1 from kinetic data.

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Dehydrogenation of isopentane with active carbon catalysts were studied in the presence of several hydrogen acceptors at temperatures from 400°C to 500°C. When ethylene, oxygen or nitrogen oxide was used as a hydrogen acceptor the the yield of dehydrogenated products from isopentane increased several times, and in stead of hydrogen, ethane, water or nitrogen was produced, respectively. The product distribution of the reaction in the presence of ethylene or a small amount of oxygen, was about the same as that of simple dehydrogenation. But when there existed a certain amount of nitrogen oxide or oxygen in the reaction system, for example 1/12-1/3 atm, the selectivity of isoprene increased markedly. Butadiene and sulfur dioxide were also effective hydrogen acceptors which gave butenes and elementary sulfur and hydrogen sulfide, respectively.
The kinetic stud y of the reaction led to the conclusion that hydrogen acceptors react with hydrogen atom on the carbon which makes of the hydrogen desorption from the catalyst thermodynamically more favorable. Thus, the apparent activation energy of the reaction decreases and the rate increases by the addition of hydrogen acceptors.

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The fixation of heavy metals by the spinel formation was proposed as one of the methods of treatment of the wastes containing the metals. The study was carried out on Cd0-Fe₂O₃mixtures as an example in order to examine the effect of spinel formation on the dissolution of CdO was observed to be restrained effectively by the following two ways: the decrease in the ratio of CdO to the mixtures at the formation of insoluble spinel and the confinement of CdO in the skeleton of spinel.
An experimental rate e quation of the spinel formation reaction was proposed as dx/dθ0=k(x_ex), where θ is reaction time, k the rate constant, and x and xe the conversion ratio to spinel at θ and θ= ∞, respectively.

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To clarify the reaction process between sodium tungstate and chlorine in the presence of carbon, the weight change of mixture of sodium tungstate and carbon on heating in a chlorine stream was examined by thermogravimetry. The volatile and non-volatile products formed by the chlorination of sodium tungstate in the presence of carbon at various temperatures were also examined by X-ray diffractometry and chemical analysis. The chlorination processes of intermediate disodium ditungstate (Na₂W₂O₇) and disodium tetratungstate (Na₂W₄O₁₃) were studied, as well, in the same way as described above.
The reaction between sodium tungstate and c hlorine in the presence of carbon occurs even at room temperature to form disodium ditungstate and sodium chloride. The disodium ditun gstate reacts with chlorine above about 270°C to form disodium tetratungstate, which then reacts with chlorine above about 290°C to form tungsten trioxide. In these reactions, sodium chloride is formed as a common by-product. Then, the tungsten trioxide thus formed reacts with chlorine above about 350°C to form volatile tungsten dichloride dioxide and tungsten tetrachloride oxide. The ratio of tungsten tetrachloride oxide in the volatile product increase s with the increase of the reaction temperature.

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Silver, gold, barium, bromine, cobalt, chromium, cesium, hafnium, rubidium, antimony, scandium, strontium, tantalum, thorium and uranium in shells belonging to Pelecypoda collected from Oligocene, Miocene, Pliocene, Pleistocene and Recent deposits in the northeastern Japan, were determined by nondestructive neutron activation analysis, to study the behaviors of trace elements in shells during the process of fossilization.
The samples were irradiated with therm al neutron in the TRIGA Mark IC Reactor of Rikkyo University (flux: 5 x 10¹¹ n/cm²/sec) for 12-47 hours. Gamma rays of the nuclides formed by the (n, γ) reactions were measured twice, i. e., for 3000 seconds after 5-9 days cooling, and for 10000-60000 seconds after 2-6 months, by using a 4096 channel GEOSCIENCE pulse height analyzer and an ORTEC Ge(Li) detector.
The relationships among the contents o f trace elements in shells, the crystal forms of calcium carbonate, and geological age were examined in statistical point of view. The content of strontium in aragonitic Recent shells and those of antimony, strontium and uranium in aragonitic Pleistocene shells were higher than those in calcitic shells of same geological age. On the other hand, thorium content in calcitic shells from. Pliocene to Oligocene was higher than that in aragonitic shells. The contents of silver, barium, cesium, hafnium, scandium and uranium showed a tendency to increase with age and the reverse was true for bromine and strontium. The contents of trace elements in the sedimentary rocks in which fossil shells were buried were also determined and the influence of deposits on the fossilization of shells was discussed. The contents of trace elements in Recent shells were compared with those in sea water, and it was found that all elements except bromine in aragonitic shells were enriched in shells from sea water.

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A high speed liquid chromatography has been applied to the analyses of phenylurethanes, diurethanes from 4-methyl-m-phenylene diisocyanate and diurethanes from 4, 4'-diisocyanatodi phenylmethane by using a porous copolymer of styrene-divinylbenzene (Hitachi Gel # 3010) for a column packing and a detector of UV 254 nm.
The urethanes were not separated by meth anol, ethanol, and methanol/hexane as a mobile phase but were separated by hexane, and methanol/H₂O. The retention time was increased by the addition of water to the methanol mobile phase. There was a linear relationship between the water concentration and the logarithmic retention time. The urethanes was eluted in the order: methyl, ethyl, propyl, butyl. The behavior of reversed-phase partition chromatography was suggested. Whereas the column efficiency (HETP) was decreased by the increase of water concentration, resolution was improved to a large extent.
The urethanes were satisfactorily separated with methanol/H₂O (80/20 vol %) as a mobile phase. A linear relationship was obtained between the peak intensity (peak height and peak area) and the concentration of the urethanes less than 6 x 10^-2 mol/l.
Quantitative analyses of the urethanes have been made possib le by the results in this work.

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The oxidation of benzoylacetone (abbreviated as BA) and its derivatives with peracetic acid has been followed iodometrically. The initial rate of the consumption of peracetic acid satisfied the following equation: Rate = { k₂ + k₃ C _H2SO4}C_BA C_AcO2H The first and second terms represent the non and the acid-catalyzed oxidation, respectively. The plots of log k₂ vs. (σ+ 1.00 Δ_r⁺) and log k_s vs. σ gave straight lines with slopes of -0.79and -0.85, respectively. The formation of several materials containing acids, aldehydes a n d an ester such as benzoic, pyruvic, benzoylformic acids, carbon dioxide, benzaldehyde, phenylglyoxal, and acetonyl benzoate were confirmed by means of GC and/or TLC. From these results, a probable mechanism which involves an epoxidation by an attack of the positive oxygen atom of peracetic acid on BA and protonated peracetic acid on BA was postulated and discussed. In this oxidation, Baeyer-Villiger reaction would take place slightly as a side reaction giving acetonyl benzoate. In addition, it was confirmed that H atom (or alkyl group) on active methylene of BA (or alkyl-substituted BA) did not migrate in our reaction condition.

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The kinetic study on the ring opening reactions of β-propiolactone with N, N-disubstituted aminodimethylstibine was carried out by means of IR spectral analyses to find the decrease in β-propiolactone (β-PL), this reaction is of second order. The reaction rate increases wit h increasing electron density on the nitrogen atom, and the substituent effect on the reac tion rate could be explained in terms of the Taft's equation. The reaction rate increas es with increasing polarity of the solvent. The existence of dipolar transition state was suggested by these facts.

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Photolysis of a benzene solution of benzophenone phenylhydrazone [7] hydrazone [8], or oxime [9] in the presence of oxygen with a high pressure mercury lamp through a Pyrex filter afforded benzophenone in quantitative yield (Table 1). In contrast to this, photolysis of a methanol solution of cyclohexanone phenylhydrazone [10] or oxime [11] in the presence of oxygen with a low pressure mercury lamp gave cyclohexanone in very poor yield (Table 1). These results demonstrated that the stability of the intermediate radical [16] (for hydrazones)and [20] (for oximes) is strongly associated with the yield of the ketones. Assumed mechanistic paths for the formation of the ketones are presented in Scheme 3 and 4. This type of photoreaction would be of practical value for the regeneration of aromatic ketones from their hydrazone or oxime derivatives.

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Upon heating an ethanol solution (50%) of ethyl α-oxo or α-hydroxyiminocarboxylates and hydrobenzamide [1] at 100°C in a sealed tube for 3 hours, 3-substituted 3-pyrrolin-2-one derivatives are formed. Active methylene compounds would react with the reactive intermediates which are produced in situ by the acid catalyzed cleavage of[1]. (C₆H₅CH=N)₂CHC₆H₅⁺ H+ → C₆H₅CH=NH+C₆H₅CH=N-CHC₆H₅+
The structures of the new products and the formation mechanisms were discussed.

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The hexane-soluble part of the coal tar pitch was separated by means of gel permeation chromatography (GPC), to elucidate the distribution of the structural unit of which the average chemical structure of pitch consists.
Nuclear magnetic resonance spectru m (NMR), ultraviolet absorption spectum (UV), molecular weight (MW) and elementary analysis were measured on the fractions, and the structural parameters of the average structural unit and the average molecule of the fractions were determined.
Molecular weight of the fractions separated by GPC was in the range of 200-280. The aromaticity index (f_a) of the fractions showed the values of 0.76-0.95. It is estimated from the degree of condensation of aromatic rings (H_au/C_a) that the average structural unit consists of 2/-5 condensed aromatic ring systems. Moreover, the average structural unit and the condensed aromatic ring system in one molecule on an average are almost the same, suggesting that the average structural unit itself forms one molecule on an average.
The frame structure of the fractions is estimated by UV and GPC ana lysis to be polycyclic pen-type condensed.

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Polymerizations shown in the following equations give polyester diols with various terminal monomer units.
The formation of these terminal units depends on the kinetics of the polycondensation reaction. The kind of terminal units is closely related to the reactivity of polyester diols with isocyanates, affecting the properties of the resulting polyurethane resin. This paper deals with the relative amounts of these terminal u nits of the polyester diols, which were found by using ¹H-NMR spectroscopy with the addition of tris(dipivaloylmethanato)europium, Eu(DPM)₃, as a shifting reagent.
The addition of Eu(DPM), to the solution of polyester diols brought about downfield shifts in their ¹H-NMR signals, which could be explained in terms of contact and pseudo contact shifts interactions. The downfield shifts were remarkable in the case of methylene protons of terminal units. Consequently, the signals assigned to methylene groups of the terminal monomer units (-COOCH₂CH₂CH₂CH₂CH₂CH₂OH, -OCOCH₂CH₂C1-1₂CH₂COOCH₂CH₂OH, -OCOCH₂CH₂CH₂Cl₂CH₂OH) could be distinguished fro m each other and also from those of internal monomer units.
In the case of the mixture of polyester diols or copolyester diols containing two or more kinds of terminal units such as -COO(CH₂)_nCH₂OH n=1, 3, 4, 5 and -OCO(CH₂)₄CH₂OH, the signals of the methylene protons, adjacent to hydroxyl group, splited into two or more peaks in accordance with the existing terminal units by the addition of the shifting reagent. The relative amounts of each terminal unit could be determined from the areas of these signals.

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These membranes were consist of cation exchange resin particles, (less than 44, μ in diameter)dispersed finely in a polypropylene matrix. By treating them with hot aqueous highly concentrated solutions of electrolytes, the heterogeneous cation exchange membranes with high ion transport number and with low specific resistance were obtained.
The influence of treatment with hot water and wi th hot aqueous solutions of various electrolytes on the membranes was studied. It was found that the above treatment is the most important one to determine the properties of the membranes. When the membranes were treated with hot aqueous solution of electrolytes, cation exchange resin particles swell and expand pushing away the polypropylene matrix of the membranes the above treatment results the formation of narrow cavities between cation exchange resin particles and polypropylene matrix, and the formation of fine micro-cracks in the polypropylene matrix. On the basis of the detailed investigation on the treatment with hot aqueous solution of sodium chloride, th e optimum conditions for the synthesis of good heterogeneous cation exchange membranes were found as follows: (1) the temperature is above 100°C, ( 2 ) more than 20 minutes treating is required and ( 3 ) the concentration of aqueous sodium chloride solution is as high as possible.

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The measurement of the ultrasonic velocity in the dilute solution of polymer revealed two kinds of compressibilities of polymer dissolved in solution.
The one of them is “compressibility of mixing unit” (k₂ and/or k₂'), which was obtained by applying the Nomoto's additivity to the polymer solution, and based on the Lennar d-Jones potential between the hypothetical mixing units of polymer.
The hypothetical mixing unit has the same chemi c a l potential as that of the segment and its volume is approximately equal to that of the solvent.
In various polymer solutions, k₂ and/or k₂' are i n herent to polymer species irrespective of the solvent or the molecular weight of polymer, as shown in Table 2 and 3. Consequently, polymer solution in MHz range was considered to be a liquid mixture com posed of the hypothetical mixing units and solvent molecules.
The other is “partial specific compres s ibility” (k₂₀) which is the partial molar quantity of the solute. The experimental results shown in Table 2, 3, and Fig.3 show that k₂₀ different from k₂ and/or k₂' changes with either good or poor solvent irrespective of the molecular weigh t of polymer in various polymer solutions.
On the basis of the examin a tion of the experimental behavior of km and the studies on the excluded-volume effects, k₂₀ was found to be dependent upon the effective volume (β) exclud ed to one segment due to the presence of another, as shown in Fig.4. Therefore, it was co nsidered that k₂₀ depends on the potential of mean-force W(γ) between the hypothetical mixin g units.
However, the above conclusions about k₂₀ are not available for the solution of polymer consisting of very poor solvent near θ state, as shown in Fig.4.
It is of interest that by the measurements of k₂₀ in MHz range, the state of polymer in very poor solvent was found to differ from that in good solvent.

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Cationic polymerization of dimethylstyrenes (DMS) was carried out with sulfuric acid as an initiator. All monomers showed large initial and saturated conversion rates. The rate constants of the Propagation reaction were calculated in terms of the kinetic treatment for nonsteady state. Both the propagation and termination rates are in the following order: 2, 4->3, 4->2, 6->2, 5->3, 5-DMS. The monomer transfer constant ratio was calculated by the relationship between the concentration of the reagent and the molecular weight of the polymer formed. On the basis of the monomer transfer and propagation rate constants, the transfer rate constant was determined. These results showed that o- or p-methyl substituted DMS tends to accelerate the propagation rate, and m-methyl substituted DMS easily brings about the chain transfer reaction toward the monomers.

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Copolymerization of 2, 4-, 2, 5-, 2, 6-, 3, 4-, or 3, 5-dimethylstyrene (DMS) with styrene was carried out by using sulfuric acid as an initiator. The monomer reactivity ratios of styrene (M₁)-DMS (M₂) are 2, 4-DMS: ₁=0.60, r₂= 4.3 2, 5-DMS: r₁=0.70, r₂=2.1 2, 6-DMS: r₁= 3.70, r₂= 0.2 3, 4-DMS: r₁=0.25, r₂=4.6 3, 5-DMS: r₁= O.40, r₂=2.0 On the basis of the propagation rate constants and monomer reactivity ratios, the rate constants of the cross-propagation reaction were calculated as follows: 2, 4-DMS: k₁₂=710, k₂₁= 430 (l/mol⋅min)2, 5-DMS: k₁₂=600, k₂₁= 46 (l/mol⋅min)2, 6-DMS: k₁₂=110, k₂₁= 3300 (l/mol⋅min)3, 4-DMS: k₁₂=1680, k₂₁= 190 (l/mol⋅min)3, 5-DMS: k₁₂= 1050, k₂₁= 16 (l/mol⋅min)

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A part of cyano groups in polyacrylonitrile was hydrated into carbamoyl groups and this influence on the thermal behavior of the polymer was examined.
The hydration of cyano groups was carried out by treat i n g polyacrylonitrile with concentrated hydrochloric acid in N, N -dimethylformamides olution. When hydrochlorica cid was added in excessd uring hydration, a part of introducedc arbamoyl groups is protonized and, consequently, a new infrared absorptionb and appears at 3400cm^-1.
The thermal behavior of residual amidified sample which does not show 3400cm ^-1 band differs from partially protonizedo ne. The initiation temperature (ca.270°) of a sharp exothermic peak in DTA curve of the former sample, measured in nitrogen, is the same as that of polyacrylonitrile but the peak temperature shifts to higher temperature side and the differential temperature becomess maller. In case of the latter sample an exothermicr eaction occurs over a wide range at a lower temperature and the initiation temperature of its exothermic peak is about 210°.
On the basis of the infrared spectral analysis, it was proved that carbamoylg roups do not initiate the thermal polymerization of cyano groups, occurred during the exothermic reacti on, but protonizedc arbamoylg roups show an ability of initiation,

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The previously reported poly (vinyl alcohol) beads were formalized and then etherified with epichlorohydrin or acetalized with bromoacetaldehyde diethyl acetal. Formalization and etherification have been performed to make crosslinking in the beads and to introduce halogen into the resin matrix, respectively. Bromoacetalization brings about simultaneous crosslinking and introducing of halogen. Strongly basic anion exchangers were obtained from the etherified or bromoacetalized poly (vinyl alcohol) beads prepared by the amination of them with trimethylamine, triethanolamine or N, N-diethyl-1, 3-propanediamine. The highest value of the total exchange capacity and the degree of swelling of strongly basic anion exchangers are approximately 2.4 meq/g and 40 ml/g, respectively. The exchangers contain quaternary, am monium groups as much as 20-100% on total exchange groups. Weakly basic anion exchangers were prepared from the above poly (vinyl alcohol) beads by amination of them with methylamine, ethylenediamine, diethylenetriamine, triethylenetetramine or tetraethylenepentamine. The highest value of the anion exchange capacity and the degree of swelling of weakly basic anion exchangers are approximately 7.0 meq/g and 24 ml/g, respectively. The bead-shaped anion exchangers obtained are moderately resistant to alkali or acid.

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Bisphenol type epoxide resin was cured with polylaurolactam and the progress of curing was followed by observing the changes in reactive groups, gel content, flow properties, X-ray diffraction patterns, molecular weight and mechanical, dynamic mechanical as well as bonding properties.
On the basis of the above observations and the chemical structure, the cured resin was found to have non-crosslinked and linear structure and its molecular weight to be about 15 X 10⁴.
Tensile, tensile shear and peel strength, and elongation increase with proceeding c ure of epoxide resin with polylauloractam.
As to amine-cured epoxide resin, tensile and tensile shear strength increase but elongation and peel strength decrease with proceeding cure.
The reason for the above differences can be explained by the following mechanisms: (a)high relaxational ability of the former due to high molecular weight and linear structure, (b) rigid structure of the latter due to short-chain crosslinking.
An excellent correlation of entanglement density ag ainst tensile strength and elongation of polylaurolactam-cured epoxide resin was found to exist.

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In the dehydrosulfurization of ethanethiol over alumina catalyst, diethyl sulfide were predominantly formed at lower reaction temperature, and ethylene was the main product at higher temperature.
Diethyl sulfide was also formed at lower temperature in the thermal desorption of ethanethiol adsorbed on alumina. Infrared absorption spectra of ethanethiol adsorbed over alumina indicated that the -SH group of the ethanethiol was dissociated and that the interaction with the catalyst surface produced the hydrogen bonding hydroxyl group.
The adsorption scheme of ethanethiol in the dehydrosulfurization was proposed.

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Binodal solid-solubility curves of ternary isomorphous oxide systems were estimated by the assumption of the regular solution. For the ternary system in which only pairs of components, 1-3 and 2-3, form continuous series of solid solutions, s 1 and s 2 respectively, it was assumed that the tie-lines were parallel to the side 1-2 (Fig.1). Then, the solubility of the binary system of s1(x₃)-s2 (x₃) was obtained by the equal tangents method through the calculation of Gibbs energy of mixing, ΔmG (x₂, x₃) = ΔmH* ( x₂, x₃) T ΔmS^id( x₂, x₃), where ΔmS^id is the entropy of ideal mixing of a ternary system, and ΔmH* is the enthalpy of mixing of s (x₃)2(x₃) binary system. The values of TΔmH* were calculated by applying the emp irical formula. Good agreement between estimated solubilities and experimental binoda l curves was found for the ternary systems of Al₂O₃-Fe₂O₃-Cr₂O₃ (1520 K) and CaTiO₃-BaTiO₃-SrTiO₃(1530 and 1700 K), for which experimental data had been available.

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The method of spectrophotometric determination of cobalt(IIII) with 6-hydroxy-5-nitroso-1, 2, 3, 4-terahydro-2, 4-pyrimidinedione (HNPD) was investigated. HNP D reacts easily with cobalt to form a water-soluble complex. Cobalt(M)-HNPD complex has an absorption maximum at 367 nm against a reagent blank. The calibration curve obeys the Beer's law over the range from 0 to 2 μg/ml of cobalt(III) at 367 nm; the molar extinction coefficient of the complex and the sensitivity are 4.05 x 10⁴ cm^-1mol^-1/ and 1.46 X 10^-3 μg⋅cm^-2, respectively, for log(l₀/l)=0.001. Large amount of iron interfered with the determination. The variation co efficient was 0.54% in the case of 10 pg/10 ml of cobalt(III). The ratio of cobalt(III) to HNPD in this complex was confirmed to be 1: 1 by the the mole ratio method.

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Upon treatment of 1-fluoro-, 1, 4-difluoro and 1, 2, 3, 4-tetrafluoroanthraquinones with concentrated sulfuric acid, 1-hydroxy-, 1, 4-dihydroxy and 1, 2, 3, 4-tetrahydroxyanthraquinones were readily obtained, respectively. Similarly, 2-fluoroanthraqUinone was also converted into 2-hydroxyanthraquione despite the low yield. Upon treatment of 3-fluorophthalic anhydrid e and p-chlorophenol with sulfuric acid, 1, 4, 5-trihydroxyanthraquinone was directly prepared. Reaction mechanism of these hydroxylation was discussed.

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The thiocarbonyl compounds [1]- [11] were found to be effective as corrosion inhibitors in acidic media.
The mo st effective compound was 2-mercaptobenzimidazole which showed 92.1 % and 100%inhibitive effect at the concentration of 32 and 250 ppm, respectively.
The effect of these compounds was found to be due to t he formation of an insoluble chelate film on the copper surface. The structure of the chelate taken from the film was identified by the comparison of its IR and FIR spectra with those of the authentic samples prepared directly from CuCl₂ (or CuSO₄) and the compounds [1]- [11].
In FIR spectra of these compounds, the characteristic absorp tion bands considered to be due to γ( Cu-ligand) and γ(Cu-C1) were observed in the range of 245-280 and 300-530 cm^-1, respectively.

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The catalytic degradation of polyethylene, polypropylene, poly-1-butene and polystyrene in the presence of anhydrous aluminum chloride was carried out. The results obtained were compared with those of thermal degradation.
( 1 ) The catalytic degradation reactions occur in the temperature range of 150-250°C which was lower as far as 100-150°C than that of the thermal degradation. ( 2 ) Cracked oil contains a large amount of isoparaffins. ( 3 ) A good deal of carbonaceous solid with small HiC value is formed. ( 4 ) In catalytic degradation of polystyrene, benzene is a main product.
On the basis of these results, the catalytic degradation reaction was assumed to proceed via carbonium ion species.

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