Phenyl radical and pyridyl radical isomers were treated by the INDO open-shell method to elucidate their total energies, charge distributions, bond orders and unpaired electron orbitals in the ground state. The calculated results suggested that pyridyl radical isomers are more stable than phenyl radical due to the delocalizability of unpaired electrons. The ESR spectra of these radicals were revealed by the calculated, spin coupling constants and compared with the observed ones. The agreement between the theoretical and observed spectra is good for phenyl radical but relatively poor for pyridyl radical isomers.
The calculated results suggested that the production of 2-pyridyl radical by the reaction of pyridine cation radical with pyridine might energetically be possible.

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NMR line widths and ¹H and ¹³C spin-lattice relaxation times T₁ have been measured on mixed solutions of a nonionic surfactant, hexaoxyethylene dodecyl ether (abbreviated a s C₁₂(E0)₆) and a fluorescent dye, sodium 2, 2' (4, 4 '-biphenyldiyldivinylene)dibenzenesulfonate (abbreviated as FD) in H₂O and/or D₂O. Narrowing of the line width of the alkyl CH₂ protons of C₁₂(E0)₆, which is related to spin-spin relaxation time T₂, takes place with increasing concentration of FD. The relaxation time due to intermolecular interaction, calculat ed from the observed T₁ and T₂, suggests an increase in the diffusion coefficient of alkyl CH₂ protons in the hydrocarbon core of the micelle. This could be explained as a result of a change of the micelle structure of C1₂(EO)₆ by the electrical charge of FD molecules trapped in th e poly ( oxyethylene) shell of the micelle. An anion-like nature of the micelle, developed as increasing amount of the FD trapped in the poly ( oxyethylene) shell, presumably cause th e diffusion of alkyl CH₂ protons of C₁₂(EO)₆ in the micelle core.

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The refractive index increment of the mixed solution of SDS (sodium dodecyl sulfate) and PVP (poly (vinylpyrrolidone)) was measured under various conditions. There are two def ini tions of the refaCtive index increment, (∂n/∂c_p)μ_s and (∂n/∂c_p)c_s. (∂n/∂c_p)c_s is a quantity measured when concentration of total SDS, c_s, is kept constant, and (∂n/∂c_p)p, is a quantity measured when chemical potential of SDS, μ_s, is kept constant.
It was found that (∂n/∂c_p)μc_s is independent of c_s, but (∂nl∂c_p)μ_s depends on c_s^f which is the concentration of free SDS when the dialysis attains equilibrium. The increments of two refractive indices are correlated with each other.
The additivity between the refractive ind ex increment of SDS and that of PVP was found. By using this principle, the amount of SDS bound to PVP (x) was calculated. The result agreed well with those obtained by analysing SDS by the Epton method. A curve connecting x and c_s^f is bell-shaped.

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A new method is presented for finding a priori all the possible mechanisms of an observed reaction. The method also gives the a priori pathways for synthesizing a target product from some starting common reagents. This very much simplifies the new field of designing organic syntheses with the aid of a computer.

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In order to have some information on the surface character of nickel boride catalyst, the h ydrogenation of some cyclic olefins over four kinds of nickel catalyst has been studied at 30°C under atmospheric hydrogen pressure.
The rates othfe hydrogenation were in the order: cyclohexene>cyclooctene over Raney-Ni (R-Ni) and the decomposition of nickel(1I) formate (D-Ni), and cyclooctene>cyclohexene over nickel boride (Ni-B) and nickel phosphide (Ni-P).
A small amount of alkali promoted the hydrogenation of cyclohexene bu t slightly depressed that of cyclooctene over all catalysts used, and the reaction rate became higher for cyclohexene than for cyclooctene even with Ni-B or Ni-P. The relative rate of hydrogenation of cyclohexene to that of cyclooctene, however, was quite different depending on the catalysts, and the order was D-Ni>R-Ni>Ni-BNi-P.
The results of competitive hydrogenation indicated that the order of adsorption strength of reactants on these catalysts was cyclooctene> cyclohexene> 3-methylcyclohexene, irrespective of the catalysts used and added acid or alkali.
The order of catalytic activity per unit surface area was Ni-B>R-Ni>D-Ni>Ni-P for all reactants used.

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In connection with the reaction mechanism of the allylic oxidation of propylene over metallic palladium, adsorption and reactivity of propylene and oxygen over Pd-black were studied at 25-100°C by means of electrobalance method and pulse reaction technique. The influence of water on the oxidation was also investigated. Adsorption measurements revealed that propylene is adsorbed in reversible or irreversible type (Fig.2); the latter becomes dominant at higher temperatures. The irreversible adsorption was further classified into at least 4 groups (Fig.8)from the reactivity toward oxidation to carbon dioxide and hydrogenation to propane. In contrast to this, propylene adsorption on palladium oxide occurs only in reversible type (Fig.3). O n the other hand, oxygen adsorption on metallic palladium proceeds irreversibly to form a surface monolayer. It was found that propylene pulse to preadsorbed oxygen gives acrylaldeh while no allylic oxidation occurs from oxygen pulse to preadsobed propylene. This suggyedstes, that, in the presence of adsorbed oxygen, only reversibly adsorbed propylene is effective for the formation of z-allylic intermeditate in allylic oxidation. It was found that water not only promotes the allylic oxidation but also depresses the total oxidation.

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Needle crystals of Zn₂GeO₄ were obtained by heating the mixed powder of 2 ZnOGeO₂*(0.5 g) with graphite powder ( 0.0 5-0.5 g) in a polcelain crucible at 1000-1100°C for 20 minutes.
The crystals are colorless and transparent whose width and length are 20-40 dua nd 7- 15 mm, respectively. The growth direction is along chexa xis. The lattice constants are ah_max = 14.23₂Å, chex=9.52_ηÅ.
Zn₂GeO₂ p owder is immediately produced from the starting mixture. of ZnO and GeO₂ at an elevated temperature. Upon reduction of Zn, GeO, with graphite powder, vapor of Zn and Ge0 with the ratio of 2: 1 evolves in a crucible. Vapor of Zn and GeO reacts again w ith oxygen to produce Zn₂GeO₄ crystals according to the following equation: 2Zn GeO+ 3/2 O₂→ Zn₂GeO₄.
Under the optimum condition (graphite powd er: 0.25 g, temp.: 1050°C) for the crystal growth, the formation rates of vapor of Zn and Ge0 are 3.6 x 10^-6 mot/sec and 1.8 X 10^-6 moli sec, respectively. The crystals grow upon reaction of these vapor species with oxygen in an air introduced into a crucible through a space between it and its lid. The flow rate of oxygen into a crucible was determined as 3.5-7.0 x 10^-6 mol/sec from the weight loss of contents in the crucible. The crystals probably grow under the excessive supply of oxygen.

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The removal of nitrogen oxides with O₃ oxidation-alkali absorption was studied as the first step of denitration of waste gases. NO-N₂ gas was mixed with an ozonized air and introduced into packing tower (50 mmφ X 700 mm, Raschig ring 10 mmφ X 10 mm), and NO_x formed was absorbed by alkaline solutions. The effects of gas flow rate (5-15 l/min), NO_x concentration (140-744 ppm), mole ratio O₃/NO (0-3), temperature of solution (6-56°C), com position and flow rate of solution (0.043-0.55 l/min), and SO₂ concentration (1000-1800 ppm) on NO_x removal were investigated. Under the optimum condition maximum removals, 85% and 95%, were obtained at mole ratios of O₂/NO of 0.5 and 1.5, respectively, because N₂O₃ and N₂O₅ formed at those ratios were absorbed more rapidly than NO₂ formed at a ratio of 1. O.
The removal was decreased with increasing gas flow rate and decreasing NO_x conc entration. When temperature was raised, removal was decreased especially at O₃/NO= 0.5 because of lowering of equilibrium N₂O₃ concentration. The composition and concentration of alkaline solution affected little on the removal. The removal by Na₂SO₃ solution was increased with increasing O₃/NO mole ratio. Sodium hydroxide concentration of 0.5% was enough to obtain a high removal decreased gradually with the increase of NaOH concentration. Removal was not affected by the presence of SO₂.

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The zirconium compounds used in this study were zirconium (IV) hydroxide (NH), zirconium (IV) chloride oxide (Cl), zirconium (IV ) nitrate oxide (NO), zirconium (IV) oxalate oxid e (OX), zirconium(IV ) acetate oxide (AC), zirconium (IV) mandelate (MA) and hydrous zirconia (B1, Bl 0.0 1, Bl 0.1). These compounds were heat-treated at 600-1300°C. The values of Δ2θ=2θ₁₁₁-2θ₁₁₁ were measured by X-ray diffractometry, where 2θ₁₁₁ and 2θ₁₁₁ are diffraction angles of (111) and (111) lines, respectively.
The samples were classified into four groups being based on the relations between Δ2θ=2θ values and the heat-treatment temperatures at 600-1000°C: (1) Δ2θ=2θ values increase to 3.25-3.27with increasing temperature from 600 to 800°C but do not change above 800°C (Cl, NH, MA, AC), ( 2 ) Δ2θ=2θ values increase with increasing temperature from 600 to 800°C and reac h a maximum value of 3.29 and above 800°C they decrease to 3.25-3.27 (NO, OX), ( 3 ) Δ2θ=2θ values increase to 3.28 with increasing temperature (Bl, B1 0.1), ( 4 ) Δ2θ=2θ values decrease to 3.2 7 with increasing temperature (B1 0.01).
At 1000-1300°C Δ2θ=2θ values of all sa mples except B1 and Bl 0.1 vary in the same manner. Decrease in Δ2θ=2θ values with increasing temperature turns to increase in them above 1100°C. At 1200°C Δ2θ=2θ values are nearly equal to 3.30 which is in agreement with calculated value obtained from the known lattice constants of monoclinic ZrO₂. The samples Bl and B1 0.1can be distinguished from others by the absence of decrease in Δ2θ=2θ values at 1100°C.
The variations of Δ2θ=2θ values were explained in terms of the stress associated with the meta stable tetragonal-monoclinic and high temperature tetragonal-monoclinic transformations.

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The method is described for the colorimetric determination of chromium (VI) in natural and waste water containing reductants.
In the presence of red uctants, the reaction of chromium (VI) with diphenylcarbazide (DPC)forms Cr (VI) - DPC chelate under alkaline condition but not under acidic condition.
In this experiment, the solution containing chromium (VI) and reductan ts was made adjust to the prescribed acidity after several minutes followed by the addition of DPC into the solution under alkaline conditions.
Recomended pH and standing time for the first reaction are 8.5 and five minutes. Optimal dose of the reagent was 4 ml of 2% of diphenylcarbazide in ethanol for the 50 ml of sample solution in final volume. Under these condition, the determination of chromium (VI) was not interfered by the following ions at the amounts indicated; sulfide (8 x 10^-6 moles), sulfite (4 x 10^-6), thiosulfite (4 x 10^-6), dithionite (4 x 10^-6), nitrate (80 x 10^-6), oxalate (80 x 10^-6), and hydroxylamine (80 x 10^-6) for 0.4 x 10^-6 moles of chromium (VI) respectively.
By the standard addition method, chromium (VI) could be det ermined even in the presence of 80 X 10^-6 moles of sulfite ion. The method should be applied for the determination of chromium (VI) containing reductants more than the amounts indicated above.

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compounds on the basis of the manometric pressure measurement of carbon dioxide. About 30 mg of sample is decomposed in a stream of oxygen and carbon was oxidized to carbon dioxide over the catalyst layer (mixture of manganese dioxide and silver oxide). The gas was trapped as dry ice by liquid air, followed by the manometric measurement of carbon dioxide expanded into a known volume. Optimum conditions for the determination was discussed in terms of amount and composition of the catalyst, duration of combustion and the flow rate of oxygen gas. Under the proposed conditions, the analysis of standard compounds gave the following statistical results. Benzoic acid:
68.848± 0.004% (Calcd.68.845%); Saccharose: 42.120±0.004% (Calcd.42.106 %); Sulfonal: 36.860± 0.014% (Calcd.36.821%); p-Chlorobenzoic acid: 5 3.621±0.076% (Calcd.53.699%); p -Fluorobenzoica cid: 59.9 64±0.016% (Calcd.60.004%); Nicotinic acid: 5 8.413±0.042%(Calcd.58.538%).

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is one of the most important problems to prepare the reliable standard solutions of extremely dilute concentration comparable to the samples.
In the present work, standard solutions of 0.1-500 ppb cadmium ions and 1000 ppb lead ions were prepared and stored in containers of glass or polyethylene. During the storage in the containers especially in glass containers, exponential decreases of cadmium and lead concentration were observed evidently. This fact was explained in terms of adsorption of the metal ions to the container walls. Effect of pH on the adsorption was also investigated in a pH range of 1-14. In the case of glass containers adsorption of cadmium occurred at pH> 6 and the adsorption became maximum in the vicinity of pH 9.5. A similar pH dependence was also observed on lead ions, stored in glass containers. The adsorption occurred at pH>3 and the maximum adsorption appeared at around pH 8.5. According to these results, the participating species with the adsorption of cadmium and lead were substantiated as Cd (OH)⁺ and Pb (OH)⁺, respectively: By taking the above facts into consideration, suitable media for stabilizing th e standard solutions were investigated and, as a consequence ethylenediaminetetraacetic acid(EDTA)was found to be the most eminent for the purpose. In practice, in the presence of 10^-4/l EDTA the standard solutions were stabilized enough for at least six months and the metal ions can be determined by the atomic absorption spectrometry (cadmium) and the differential pulse polarography (lead) without special interference due to the presence of EDTA.

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A method for the determination of ppb level of iron has heen developed by utilizing its catalytic ability to increase the oxidation reaction rate of Bindschedler's Green leuco base (4, 4'-bis (dimethylamino) diphenylamine, BGL) by hydrogen peroxide. BGL was oxidized to Bindschedler's Green (BG⁺) which showed a maximal absorbance at 725 nm. The initial reaction rate was estimated by the fixed-time method, the maximum absorption wavelength of BG⁺ being measured spectrophotoxnetrically.
Catalytic reaction m echanism was proposed as follows The rate constants and equilibrium constant were estimated as k₁=8.2 x 10³mol^-1⋅l⋅min^-1, k₂= 4.5 x 10⁵mol^-1⋅l⋅min^-1 and K_h=10^-4.8mol⋅l⋅min^-1 at 25°C.
The oxidation reaction proceeded in pseudo zero o rder to BGL (Fig.2), the reaction rate being related linearly only with the iron concentration. Under the proposed conditions, trace iron up to 100 ng/25 ml could be determined by measuring the absorbance at 10 min after the initiation. By adjustment of variables affecting the absorbance such as reaction period and temperature (Fig.5), sensitivity could be elevated to 0.5 ng-Fe/25 ml. Since BG⁺ showed an apparent molar absorptivity of 10⁷-10⁸ (Table 2), this method was 1000-10000 times more sensitive than 1, 10-phenanthroline method.
Among diverse metal ions, copper (II) exhibited a significant interference (Table 3), which could be estimated by masking iron with an addition of F^- (Table 4). Then the net effect by iron was determined by substracting the interference due to copper from the overall reaction.
Trace iron in tap water and in highly pure cadmium (Table 5 and 6), and soluble iron in water can be determined satisfactorily by the proposed method.

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r-acetylene flame, ammonium perchlorate (5 x 10-1 m ol/l) increases the absorption of ytterbium (50 ppm) by about 29 times. The enhancing effects of HCl, HNO₃, HBr and HClO₄ in the range of 1O^-4-1O^-1 and the depressing effect of HI in the range of 10^-4-10^-3 mol/l are eliminated by the addition of ammonium perchlorate (5 x 10^-1mol/l) which enhances the ytterbium absorption. But remarkable depressing effects of H₂SO₄ and H31₃PO₄ can not be eliminated sufficiently.
The effects of common cations except Al³⁺ or Na⁺ and rare earth elements are eliminated by the addition of ammonium perchlorate. Yb₂O₃ added to La₂O₃ is determined by the atomic absorption method without lanthanum interference by the addition of ammonium perchlorate.
The calibration curve for ytterbium in the presence of ammonium perchlorate (5 x10^-1 mol/l )is linear in the range of 0-50 ppm and it gives more sensitivity by about 29 times than that of ytterbium alone.

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The half-wave potential of Pb²⁺ ion in dimethyl sulfoxide (DMSO), N, N-dimethylformamide (DMF) and propylene carbonate (PC) is shifted to the negative side on the addition of halide ion (X-). The shift of the half-wave potential decreases in the order Cl^->Br^->I^- among the X ions, and in the order PC>DMF>DMSO among these three solvents. This fact shows that a highly stable complex is formed in PC with the smallest donor number among these solvents. In the presence of excess X^- ion in DMSO, the complexes of PbCl3^-, PbBr⁺ and PbI⁺ are formed. On the other hand, the complexes of the type PbX4^2- are formed for ev ery X ion in DMF and PC.
In DMSO and DMF solutions, the diffusion current of Pb²⁺ ion in the presence of X ion increases for Cl and Br ions, while it remains constant or decreases for I^- ion. The increase of diffusion current (or diffusion coefficient) can be explained well by the replacement of the solvent molecules solvated to Pb² ion by X^- ion. Because the diffusion coefficient increases in the cases of Cl^- and Br^- ions, the molecular weight being smaller than those of the solvent molecules released by replacement. On the contrary, it remains constant or decreases in the case of I^- ion, the molecular weight being greater than those of the solvent molecules released by replacement.
In PC solution, the reduction wave is separated into two waves (the first and second waves)at C_x/C_pb (mole ratio) ≤ 2. The first and second waves correspond to the reduction waves of free Pb²⁺ and PbX⁺ ions, respectively. The precipitate of PbX₂ appears in PC in the range of C_x/C_pb≤3. The precipitate dissolves completely to produce a soluble complex in range of C_x/C_pb>3. The diffusion current for the soluble complex is larger than that of the Pb²⁺ ion appeared in the absence of X^- ion. The diffusion current decreases slightly by the addition of excess X^- ion. The decrease is caused by the increase of viscosities of PC solutions.

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A strip of homogeneous cation-permselective ion exchange membrane of the hydrogen form (Ashiplex CK-1, 2 cm in width, 0.02 cm in thickness and 30-50 cm in length) was placed in a migration apparatus (Fig.1). The behaviour of the mixed band containing two alkali metal ions (couples of Cs⁺-K⁺, Rb⁺-K⁺ and Na⁺-K⁺) followed by Li⁺-band, was observed by passing a constant direct current of 20 mA. As the electromigration proceeded, the length of the mixed band decreased and two new bands, each of which consisted of single alkali metal ion, appeared at the front and the rear of the mixed band. It was also observed that the sum of transport numbers of cations in the mixed band was unity and each band moved with all the same constant velocity, in other words, with an ideal “ isothachophoresis”. The order of the mobility in the membrane, K⁺>Rb⁺>Cs⁺>Na⁺ > Li⁺, was ascertained both by electromigration experiments and by conductivity experiments (Table 1). It was demonstrated that the couple of Rb⁺-Cs⁺ was easily separated to produce pure alkali metal ion by the present procedure without using any complex forming reagent.

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Sodium benzenesulfonate (BS), sodium p-toluenesulfonate (PTS), and sodium m-xylene-4sulfonate (MXS) in detergents were determined by high speed liquid chromatography employing a micro spherical strong anion exchanger (TSK-Gel LS-222 6 μ) as a column packing.
BS, PTS, and MXS in the column effluent were monitored by a spectrophotom etric detector at 220 nm. The column used has good performance as shown in Fig.1. Elution times of BS, PTS and MXS were decreased with the increase of perchloric acid and methanol concentrations in the eluent, the increase of column temperature also decrease the elution time (Figs.2, 3 and Table 1). The recommended conditions for the analysis were as follows: column; 5 mm I. D. and 50 mm in length, eluent; 0.2 mol/l perchloric acid-methanol/water (1/9 v/v), column temperature; 40°C, flow rate; 1.3 ml/min. Ingredients in detergents did not interfere the analysis, because inorganic and organic builders which did not absorb light at 220 nm were eluted earlier than BS, and higher alkylbenzenesulfonates, main components in detergents, were strongly held by the anion exchanger. Calibration curves for BS, PTS and MXS were linear within a range of 1-7 μg, respectively. Recoveries of BS, PTS and MXS for known samples were satisfactory. By using this method, lower alkylbenzenesulfonates in several commercial detergents were determined without any interferences.

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n the commercial reagent grade naphthalene were carried out by gas chromatographic method. Benzo[ b ]thiophene and 2-methylnaphalene, contained as a relatively large amount of impurities in the naphthalene were detected directly with flame ionization detector (FID). Benzo[ b ]thiophene whose con centration in the naphthalene being lower than 20 ppm could be directly determined with flame photometric detector (FPD) up to 1 ppm.
To the naphthalene, whose impurity concentration being lower than the limit of detection of FID or FPD, the preconcentration technique by rapid zone melting was applied and additional 9 impurities, such as indan, indene, tetralin, 1-methylindene, 1-methylnaphthalene, 2-methyl benzo[ b ]thiophene, quinoline, 2, 6-dimethylnaphalene and biphenyl, were identified by gas chromatography-mass spectrometry.
The commercial spec ial grade naphthalene containing ca. 0.5% impurities was purified by zone melting method and recrystallization. Rapid zone melting conditions for concentration of impurities and purification of the naphthalene were evaluated and the best condition was found as follows: rotation speed is 125 Hz, alternating period of rotation is 0.4 sec and zone travel rate is 60 cm/hr. For the naphthalene containing large amount of impurities, rapid zone melting after recrystallization was found to be effective.

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of small amounts of CO gas with a new type of color-producing tube, which is improved conventional gas detector tube and may be referred to as total conversion type color-producing (TCC) tube, was described following the previous report on the determination of NO_x.
The supported color-producing reagent was prepared by uniform lower temperature drying of the aqueous solution of reagent (O.20% Pb(NO₃)₂, 1.6% HNO₃, and 20% H₂O) on 60-80mesh particles of specially purified silica gel and calcination at 500°C. This extremely light yellow reagent was shown to react with CO gas producing deep dark brown color, and the coloration was found to proceed instantaneously up to completion (1 mol Pd(NO₃)₂ consumed 0.70 mol CO).
The TCC tu be, constructed of glass tube of 1-3 mm in diameter and less than 80 mm in length filled with the color-producing reagent, was tested for CO analysis by measuring th e length of coloration with 20-250 ml samples of diluted CO gas and with a flow rate below 35 ml/min. The tone and intensity of coloration were observed to be constant and uniform throughout the length of coloration, irrespective of temperature and CO concentration. Excellent linear relation between the length of coloration and the total quantity of CO in the sample was established in every case. Thus, 2500-4 ppm of CO can be determined with a precision of average relative error 2.5% by the suitable use of TCC tube with diameter of 3, 2 or 1 mm.

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Irradiation of mixtures of 2-pyridones and acrylates or acrylonitrile gave a novel type of photoadducts, 3-substituted 3, 4-dihydro-2 (1H)-azocinones [1] and three types of [2+ 2]cyclo adducts. The formers were ring-expansion products which were considered to be formed by a new type of photoreaction and the latters were endo-7-substituted cis-3-azabicyclo[4.2. O]oct-4en-2-ones [2], exo-7-substituted cis-3-azabicyclo[4.2. 0]oct-4-en-2-ones [3], and exo-7-sub stituted cis-2-azabicyclo[4.2. 0]oct-4-en-3-ones [4]. As main products in these reactions were compounds of type [3], the addition-orientation was fairly regioselective. The structures of these photoadducts were mainly determined by PMR, ¹³C-NMR, and MS spectra and by the use of NMR shift-reagents.
Solvent-effec ts on the reaction of N-methyl-2-pyridone with methyl acrylate were also examined. Then, [1 a]/[3 a] ratio was 0.09-0.3 6, which was larger in protic solvents and [4 a]/[3 a] was 0.0 5-0.15, which was larger in polar solvents.

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1, 4-Disubstituted 2, 6-piperazinediones were allowed to react with chloranil in benzene and 1, 3-dipolar cycloadducts were obtained. The reaction may proceed via the formation of unstable mesoionic intermediate through dehydrogenation of piperazinediones by chloranil followed by cycloaddition of chloranil to the intermediate. When the reaction was carried out in the presence of N-phenylmaleimide, the cycloadduct of the mesoionic intermediate with N-phenylmaleimide was obtained. The yield of cycloadducts was highest (59%) when the piperazinedione have a phenyl substituent at position 4.

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The reaction of 1-butene has been investigated over various WO₃-SiO₂ catalysts. As shown in Fig.1, for the disproportionation of 1-butene kneaded catalysts are superior to impregnated catalysts. DTA curves and X-ray diffraction patterns show the existence of free WO₃ in all impregnated catalysts and in the kneaded catalyst containing 8 or 10 wt % of WO₃. But, in the kneaded catalyst containing 5 or less wt % of WO₃, free WO₃ is scarcely recognized. The active site for the disproportionation would intimately relate to the well dispersed WOprobably combined with silica. The isomerization activity of impregnated catalyst, whose WO₃ content being lower than 8 wt %, is higher than that of kneaded catalyst containing the s ame amount of WO₃ as the former one. The activities of both impregnated and kneaded catal y sts increase linearly with increasing WO₃ content in the range of 0-5 wt % of WO₃. The double bond migration seems to be caused by the originally existing site on the silica and by th e site formed by the mixing of WO₃ with silica. The isomerization is inhibited by a small amount of alkali metal. The double bond migration may occur on the acidic site of the catalyst. The ability of alkalis for the retardation of double bond migration is in the following or d er: Cs>K>Na. This order agrees with that reported about MoO₃Al₂O₃ catalyst. Large amounts of alkali metals interfere with the disproportionation; consequently, the improvement of selectivity is restricted.

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Finely powdered copper phthalocyanines were prepared by the reaction of 1-amino-3-imino isoindolenine nitrate with copper (II) hydroxide. The product was obtained in better yield when the glycerol containing urea was used as a solvent and the temperature of the reaction was maintained at 140°C for a few minutes under vigorous agitation. The product was filtered at 80-90°C, then the solid was washed with dilute hydrochloric acid, dilute sodium hydroxid e solution, hot water, and ethanol successively, and dried at 80°C.
The product is polymorphous metastable α-form with a c haracteristic peak 2 θ = 8.5 ° (d= 10, 40å ) in the X-ray diffraction pattern. A hue of the product is brilliant blue (λd= 475.9 nm)and the particle size of the product is 0.1, -0.5 μm.

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4, 4'-[2, 7-Fluorenylenebis (iminocarbonyl)]diphthalic dianhydride (FBTA) was prepared by the solid phase condensation reaction of 4 (cliloroformyl) phthalic anhydride with 2, 7-fluorenediamine. Polyamide-imides were synthesized by the bulk polycondensation reaction of FBTA with aromatic diamines at high temeratures, and the reaction conditions were investigated. As an aromatic diamine, p-phenylenediamine, 4, 4'-diaminodiphenylmethane, 4, 4'-diaminodiphenyl ether, 4, 4'-diaminodiphenyl sulfone or 2, 7-fluorenediamine was used.
The polymers, [1]-[5], are insoluble in organic solvent such as DMF, DMAc or DMSO, and slightly soluble in conc.H₂SO₄. Reduced viscosities of polymers increased with increasing reaction temperatures. Reduced viscosities of polymers obtained at 300°C were measured in conc. H₂SO₄ solution at 30°C and their values are 0.09-0.43.
From the thermal analyses, it was found that these po lymers decompose at 450-600°C in nitrogen atmosphere.

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Neither hexaamminecobalt (III) chloride, [Co (NH₃)₆]Cl₃ nor tris(ethyenediamine)cobalt(III)chloride, [Co(en)₃]Cl₃ can initiate the photopolymerization of acrylamide in an aqueous solution, but in the presence of potassium thiocyanate these complexes are found to sensitize the photopolymerization markedly.
The rates of photop olymerization sensitized by the complex-potassium thiocyanate mixtures are roughly dependent on the square root of the concentrations of both complexes and thiocya nate. In the case of [Co(NH₃) ₆]Cl₃, the rate of polymerization is directly proportional to the concentration of acrylamide, but in the case of [Co(en)₃]Cl₃, the order of the overall reaction is of ca.1.7 with respect to monomer concentration, indicating that monomer is involved in the initiation step.
Spectroscopic investigation of these mixtures showed that a significant change in absorption spectrum is due to the formation of an ion-pair between a complex cation and a thiocyanate anion. Further, the formation of a transient radical, which is identified as (SCN)₂⋅^-, was confirmed by a flash photolytic study.

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Graft polymerization of styrene onto ethylene-vinyl acetate copolymer (EVAc copolymer, VAc contents: 28.5 and 33.0 wt %) initiated by azobisisobutyronitrile was studied. EVAc copolymer was partially bydrolyzed by alkali to form OH group on the copolymer backbone. The partially hydrolyzed EVAc copolymer was esterified by maleic anhydride. Styrene was graft polymerized onto esterified EVAc copolymer by using azobisisobutyronitrile as an initiator. Maleic acid group of esterified EVAc copolymer may form complex with styrene and the radical graft polymerization may be initiated from this complex. In this graft polymerization, the rate of polymerization is the same as that of homopolymerization of styrene and the graft efficiency is very high.
Physical properti es of graft copolymer are as follows: Tensile strength: 150-170 kg/cm²; Tensile elongation: 320-500%; Tensile impact strength: 250-500 kg/cm².
Number average moleculer weight (M_n) of graft polystyrene is about 10000, measured by GPC, and M_w/M_n is about 1.5.

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Thermal decomposition of polystyrene was studied in a batch with fluidized bed, 35 mm ID, at 380-550°C, in a nitrogen or an air, whose pressure and flow rate being one atmosphere and 2.0 to 4.0 cm/sec, respectively.
The overall reaction is of the first order. The contact particles used were silica gel, silica sand, serpentine, magnetite sand, silica balloon, tire char and glass beads. The yield of oily product, amount of styrene monomer and rate to thermal decomposition of polystyrene are almost independent of the size of contact particles. However, different results are obtained with different contact particles. When magnetite sand or silica sand is used in an air, an oily product is formed from polystyrene in 70-80% yield, with higher rate constant and with more amount of styrene monomer than the case using other particles.

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In an aqueous solution of constant concentration (C_L) of sodium p-methylbenzenesulfonate (MBS) or p-dodecylbenzenesulfonate (DBS), the adsorption rates of the above solutes on a granular activated carbon were measured at 20°C in an agitated tank. The intraparticle diffusivities which refer to the concentrations of adsorbate in particles (D_i') or in so lution (D_l), the surface diffusivity (D_s) and the pore diffusivity (D_p) were investigated.
D_l' is not changed by the adsorption ratio (F=Q_t/Q_∞) in the adsorption of DBS and in the adsorption of MBS when the ratio is smaller than 0.6 (Fig.2-4). Consequently, the concen tration of solution in particles (C_p) was considered to be constant as far as D_i' was constant. D_i'changes greatly with C_L' (Fig.5, 6). The pore diffusion controls the intraparticle diffusion when CD_L'is more than 10^-3 mol/l, but the surface diffusion controls it when C_L is less than 5 x 10^-5mol/l. D_s is determined by the interpolation of D_i' to be 2 x 10^-9 or 1 x 10^-10 cm²/sec for the adsorption of MBS or DBS, respectively. D_p is calculated from parallel pore model to be approximately 5 x 10^-7 or 3 x 10^-7 cm²/sec for the above two cases, again respectively. D, was estimated to be 1/2-1/14 times of the molecular diffusivity in an aqueous solution (D_L).

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Na⁺ content in bayerite usually amounting to about 0.7% could be economically diminished to about 0.05%. The process includes the treatment with CO₂ on concentrated aqueous slurry of bayerite, for example, at 170°C for about 5 hours under a pressure of 40 kg/cm² of CO₂ in an autoclave. The product is free from any contaminations during the treatment and the concentrations of impurities other than Na⁺ are invariable. When the treating temperature exceeds 180°C, bayerite changes to boehmite, which causes some reduction of particle size.

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[in Japanese]

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Amination of potassium m-toluenesulfonate (m-TSK) with sodium amide, in liquid ammonia at 130°C for 7 hr gave m-toluidine in 91% yield. Higher selectivity for meta amination was acquired at somewhat a lower temperature and by a longer time, for example at 115°C for 9 hr it was as high as 99.9%. Sodium alkylamide (R= Et, Bu) which was prepared by the reaction of RNH, with sodium amide, reacted with m-TSK in RNH2 at 140-165°C for 6-10hr to give 85-91% of N-alkyl-m-toluidine accompanied with small amounts of m-toluidine and R₂NH (R = Bu) Phenylamination of m-TSK with sodium anilide in aniline, DMA or xylene at 185-225°C for 6-8.5 hr gave N-phenyl-m-toluidine in 88-92% yield, and the formation of m-toluidine was not observed in this case.

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The ring-opening addition of 3-(substituted methylene)phthalides ([1] and [2]) with amines forming benzamide derivatives [4] was investigated. The reactivity of phthalide was greatly enhanced by the introduction of an exocyclic carbon-carbon double bond onto the 3-position of phthalide, and [1] and [2] a kind of enol lactones, reacted readily in N-methyl- 2-pyrrolidone with aliphatic amines at room temperature, as well as with an aromatic amine at 80°C.3-(Substituted methylene)thiophthalides [3], sulfur analogs of phthalides, were much less reactive than the corresponding 3-(substituted methylene)phthalides toward amines.

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Water-insoluble precipitates were obtained by mixing hydrochloric acid solution of sodium dextransulfate (DS) and that of chitosan in various concentrations.
The mole ratios of N/S in polyelectrolyte complexes (PEC) from A-1 to B-3 are from 0.79 to 2.51. It was found that the concentration of the reactants, the melecular weight of DS, and th e concentration of acid in solution affect the ratio of chitosan to DS in the polyelectrolyte complex produced.
IR spect roscopic studies revealed that the structures of polyelectrolyte complexes of A series are different from those of B series, although both polyelectrolyte complexes have common constituents.
All polyelectrolyte complexes of A series are insoluble, even if they are heated in popular organic solvents. But, the polyelectrolyte complexes of B series are soluble or partially soluble in dimethyl sulfoxide md in the water/potassium bromide/aceton mixture (60: 20: 20 by wt% )at elevated temperatures.
Blood tests were performed by measuring the weight of thrombus formed within an appro priate interval of time, after calcium chloride solution was added to ACD blood which had been in contact with PEC. A firm clot is scarecely formed up to 15 min, after calcium chloride solution was added to ACD blood on the polyelectrolyte complexes of A series. On the contrary, the polyelectrolyte complexes of B series enhance the coagulation of ACD blood.

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In order to obtain fundamental data on the production of peroxyisobutyric acid, vapor phase oxidation of isobutylaldehyde has been studied at 100-230°C for residence time of 10-80 sec and with the concentration of the reactants over explosive limit (concentration of isobutvl aldehyde was 78%). Below 180°C, the main by-product was isobutyric acid, but above 180°C, an increase of temperature and residence time increased the decomposed products such as isopropyl alcohol, CO, CO₂, propane, propylene. The selectivity of peroxyisobutyric acid was decreased (Fig.1, 2). Reactivity of isobutylaldehyde was so much higher than that of acet aldehyde that mixing of ozone did not influence the reaction.

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A new organic pigment, 5-(5, 6, 7, 8-tetrabromo-2, 3-naphthalenedicarboximido)-3'-hydroxy henzoquinophthalone (2 (3-hydroxy-2-quinoly1)-5-(5, 6, 7, 8-tetrabromo-2, 3-naphthalenedicarbox imido)-1 H-benz[ f ]indme-1, 3(2H) -dione), has been prepared to get a substitute for Cadmium Yellow (CdS). The quinophthalone is similar to CdS in color and has good pigment properties, being resistant to light, heat and organic solvents.
Several 5-(substituted phthalimido)-3'-hydrox ybenzoquinophthalone derivatives were synthesized by the reaction of 5-(substituted phthalimido)-2, 3-naphthalenedicarboxylic anhydrides with 3hydroxy-2-methylquinoline-4-carboxylic acid. The contribution of the 5-substituted phthalimido groups in these compounds to some properties as a pigment was discussed.

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The cis-1, 4 polymerization of isoprene catalyzed by Ti(OBu)₄-AlEt₃-Br₂ mixtures is inhibited by the addition of NaCI. The catalyst, prepared by the addition of NaCl (10-15 mol% on AlEt_s, viz., NaCl being equimolar with Ti(OBu)₄) and then Ti(OBu)₄ to the reaction mixture of AlEt₃ and Br₂, greatly inhibits the polymerization of isoprene. These results were considered to be due to the form ation of complex between NaCl and AlEtBr₂; AlEtBr₂ exsists in both liquid and solid phases of the catalyst and is necessary species for the formation of active sites.

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A simple microdetermination of selenium in organoselenium compounds has been carried out. Selenium in the sample is oxidized quantitavely under the presence of oxygen in Schoniger flask and the resulting selenious acid was absorbed in 10 ml of aqueous 1% NaOH solution in the flask during 30 min. Selenium in the absorbent was determined by the absorbance measurement at 420 nm by means of 3, 3-diaminobenzidine method.
The proposed, method is very convenient, highly reproducibl e, and accurate to within ±0.4%for samples containing 0.8-2.4 mg of selenium.

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It is well known that phosphate or fluoride ion interferes with the determination of Ca or Fe by atomic absorption spectroscopy and such interference is removed by the addition of organic substance such as EDTA.
This report deals with th e removal of the interference by the addition of carbon, to utilize its paucity of ionic adsorption. Carbon black powder saitsfactorily removes the interference occurred in the spectroscopic determination of the elements, such as Al and Ti having a strong affinity for oxygen, in air-acetylene flame. Further work is now in progress.

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