The solubilities of 1-dodecyl-2-pyrrolidone (D. P.) were determined in aqueous solutions of various kinds of addends by measuring the optical density at 550 nm and 25°C.
When electrolyte such as NaSCN is added in the solution, the solubility of D. P. increases, while electrolyte such as NaC1 decreases the solubility of D. P. These facts may lead a conclusion that the solubility of D. P. depends on the water structure in the aqueous solution of the addend.
Among poly (vinyl alcohol) (PVA), poly (ethylene glycol) (PEG) and poly (vinyl pyrrolidone)(PVP) with almost the same degree of polymerization, PVA is the most effective and PVP is the least effective on increasing the solubility of D. P. Since D. P. has positive charges more or less in aqueous solution, the polar groups as well as the hydrophobic groups of these polymers affect the solubility of D. P. As for PEG, the solubility of D. P. increases with the increase in the degree of polymerization.
The solubility of D. P. increases with increased amount of sodium dodecyl sulfate (SDS), as satisfies the relation of SDS/solubilized D. P. =1/2 in mole ratio. This solubilization is observed even under the critical micelle concentration (CMC) of SDS, and the aqueous solution shows the anomalous viscosity of dilatant flow. The suspension of Japanese Acid Clay is stable in aqueous solution of SDS, but not stable in aqueous solution of SDS with D. P. It is, threfore, concluded that there is a specific interaction between SDS and D. P., probably the formation of large mixed micelle.
The fact that the rate o f increase of the optical density above the solubility of D. P. decreases with increasing of the solubility of D. P. seems to indicate that the average radius of D. P. droplet of the emulsion decreases with increased affinity of the solvent to D. P.

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Ethylene polymerization has been studied kinetically with a soluble Ziegler-Natta catalyst. At molar ratios of Al/Ti not smaller than 2, the polymerization rate increased rapidly with the polymerization time and reached a maximum value, and then it started to reduce immediately. The rates during the rate reduction process, R, were expressed by the following equations.
Where R₀ and R₀', were hypothetical initial polymerization rate obtained from the rate reduction processes by the extrapolation of the polymerization rate to zero time.
At lower catalyst concentrations ([ (C₅H₅)₂TiCl₂]< 10^-2 mol/l), the decay constant k_t was independent of the concentration of catalyst component and ethylene pressure. Therefore, it was concluded that the reduction was due to the self-deactivation of polymerization centers. R, was expressed as follows:
It was presumed that 1 mol of (C₅H₅)₂TiCl₂, 2 mol ofEtAlCl₂ and 1 mol of ethylene participated in the formation of polymerization centers, and excess EtAlCl₂ inhibited the polymeriza tion reaction reversibly.

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The co-pyrolysis of 1, 1, 2-trichloroethane (TCE) and diethyl ether on activated alumina wascarried out in order to elucidate the catalytic mechanism for the reaction of CH₂ClCHCl₂+Et₂O = CH₂=CCl₂+EtCl+EtOH (1)
Reaction (1) was found to proceed according to Rideal-Eley's mechanism . The elementaryreactions consist of the following three process :
A+ l⇔ Al ( 4 )
Al+B⇔ Rl+S ( 5 )
Rl⇔ R+l ( 6 )
The symbols A, B, R, S and l represent TCE, diethyl ether, dichloroethylenes, ethyl chloride andthe active vacant site on alumina, respectively.
The kinetic data are in agreement with the equation based on the desorption controlling stepon a single-site of the catalyst:
where k is the rate constant, and P_A, P_B, P_R and P_S are the partial pressures of TCE, diethylether, dichloroethylenes and ethyl chloride, respectively. K and K_S in equation ( 9 ) represent the equ ilibrium constants denoting K_A·K_r·K_R and K_A·K_r, in which K_A, K_r and K_R are the equilibrium constants for equations ( 4 ), ( 5 ) and (6).

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The catalytic activity of cold-worked platinum for the oxidation of hydrogen was markedly decreased by annealing under vacuum in the temperature range of 400-500°C. In the case of the hydrogenation of ethylene, the change of the catalytic activity takes place in the range of 150-400°C. These temperature ranges agree with those of disappearance of the dislocations and point defects produced by cold-working, respectively. This fact indicates that the active sites on the platinum for the two reactions are different from each other. The catalysts annealed at high temperatures (deactivated catalysts) were reactivated by a chemical treatment of the surface such as oxidation in O₂ at above 200°C followed by reduction in H₂. However, this recovered activity was decreased by the subsequent annealing under vacuum in the range of 350-400°C. It seems reasonable to assume that the active sites generated by the chemical

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The spectral sensitization of silver chloride using dyes has been studied electrochemically by measuring the dye-sensitized photocurrent. The following electrochemical cell was constructed: Pt ( I ) /electrolyte ( I ), dye/AgCl/electrolyte ( II ) /Pt ( II ), where the dimension of the silver chloride crystal was 8 x 8 x 0.5 mm. Dyes used as senitizesrs were 1, 1'-diethyl-2, 2'-quinocyanine chloride, 3, 3'-diethylthiacarbocyanine iodide, fluorescein, etc. Since the dark current was greater by a factor of more than 10³ than the photocurrent, a light chopper and a lock-in amplifier were used to determine the photocurrent selectively.
It was found that the sensitized photocurrent incr eased with increasing concention of the dye up to about 10^-4 mol/l, then attained a saturated value. This behavior was interpreted in terms of the Langmuir adsorption of the dye to the silver chloride crystal. It was observed that the sensitized photocurrent increased remarkably with increasing concentration of silver ions in the electrolyte solution ( I).
The results obtained in the present study were in good agreement with those obtained in the photographical investigation.

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The electrode potentials of tantalum chlorides in molten potassium chloride were measured by using a silver-silver chloride reference electrode. Potentials of the reference electrode was referred to a chlorine electrode in the temperature range from 775 to 875°C.
The standard potentials, E_Ta/Ta(II)⁰ and E_Ta/Ta(IV)⁰ and the redox potential E_{Ta(II)/Ta(IV)}⁰ were determined as fnllnws:
(A) E_Ta/Ta(II)⁰/V=- 1.6 7+6.4 X 10^-4T/°K (V) up to 4 x 10^-4mele fract.
E_Ta/Ta(IV)⁰/V=- 2.01+7.7 X 10^-4T/°K
E_{Ta(II)/Ta(IV)}⁰/V=- 2.35+9.0 X 10^-4T/°K
(B)E_Ta/Ta(II)⁰/V=- 1.74+7.2 X 10^-4T/°K above 4 x 10^-4 mele fract.
E_Ta/Ta(IV)⁰/V=- 1.65+5.0 X 10^-4T/°K E_{Ta(II)/Ta(IV)}⁰/V=- 1.56+2.8 X 10^-4T/°K
The equilibrium constants (K) of the reaction Ta (IV) +Ta=2Ta (II) in the melt were expressed in the following equations.

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Needle crystals were prepared by the addition of ethyl alcohol to aqueous 6 N potassium hydroxide solution saturated with zinc oxide and characterized by means of DTA, TG, X-ray diffractometry, flame photometry and chemical analyses.
The results reveled that these needle crystals were represented as KZn (OH)₃·3H₂O.
These crystals are supposed to decompose at around 600°C as shown in the following equations.KZn(OH)₃·3H₂O→ KZn(OH)₃ + 3H₂O ↑ at 117°C
2KZn(OH)₃ → 2ZnO + 1/2 K₂O₂↑ + K↑ + H₂O↑

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The authors have recently reported that TiO₂ powder with high rutile-form content can be produced by vapor phase reaction of TiCl₄-H₂-CO₂ system. In this work, the formation of TiO₂ powders from the TiCl₄-H₂-CO₂ and the TiCl₄-H₂O-H₂ systems was studied with emphasi s on the effects of reaction conditions on the formation of rutile-TiO₂.
( 1 ) In the reaction of the TiCl₄-H₂-CO₂ system, the content of rutile-form increased remarkably at around 900°C and became more than 90% at temperatures above 1000°C (Fig.2). The contents of rutile-form could be 100% by introducing reactant gases into the higher temperature zone of reactor (Method (B) in Fig.1 ( I )). Usually, the products had oxygen deficiencies and were black to white. The colored products became white by heating up to ca.700°C (Table 1). The average particle-size of the products was the range from 0.05 to 0.95, um (Fig.6, Table 2).
( 2 ) In the reactio n of the TiCl₄-H₂O-H₂ system, the content of rutile-form incresed rapidly in the temperature range from 800° to 900°C and was 100% at 1000°C (Fig.2). The products were bluish. The average particle-size of the products was in the range from O.05 to 0.08 μm (Fig.6, Table 2).
( 3 ) Among s everal reaction systems examined hitherto, the rutile-TiO₂ content in the products increases in the order of TiCl₄-O₂ system <TiCl₄-H₂O system < TiCl₄-H₂O-H₂, system, TiCl₄-H₂-CO₂ system (Fig.2), indicating that the formation of rutile-TiO₂ is facilita ted in reducing atmosphere. This suggests that the transition of an anatase-like cluster to the rutile one is accelerated by the partial reduction of the cluster (Fig.10).

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When phosphate rock is ground, its solubility in 2% solution of citric acid is much increased and its utility value for phosphate fertilizer is also increased without any treatments such as acid decomposition and melting.
For example, the citri c solubility can be increased from 34% to 92% for Florida phosphate rock and from 13% to 74% for Kola phosphate rock by 60 hours grinding. Although increases of solubility and reactivity depend on dividing of particle and increase of structural distortion by grinding, the change from fluorapatite Ca₅F(PO₄)₃ to hydroxyapatite Ca₅OH(PO₄)₃ with defluorination by the mechanochemical reaction between fluorapatite and silica (mainly quartz)in phosphate rock is not negligible as the other cause.
The defluorination as found in phosphate rock is recognized during grinding the mixture of pure calcium fluoride and quartz. This phenomenon is also found in synthesized fluorapatite quartz system, and the change from fluorapatite to hydroxyapatite is confirmed from the analysis of X-ray diffraction pattern and infrared spectra. The citric solubility can be raised up to 92% by grinding alone in the case of Florida phosphate rock having fine particle of apatite and sufficient amount of quartz for defluorination and up to 85% by grinding with additive quartz as atomic ratio F/Si 4 in the case of Kola phosphate rock having coarse particle of apatite and insufficient amount of quartz for defluorination.

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The interlayer cations in synthetic expandable layer minerals such as Li-taeniolite [LiMg₂Li·(Si₄O₁₀)F₂] and anhydrous Na-fluoro-hectorite [Na_1/3Mg_2(2/3)Li_1/3(Si₄O₁₀)F₂] were con firmed to be ion exchangeable, Ton exchange of interlayer cation by various cations, such as Li⁺, Na⁺, K⁺, Rb⁺, Cs⁺, Mg²⁺, Ca²⁺, Sr²⁺, Ba²⁺ Co²⁺, Mn²⁺, Ni²⁺, Cd²⁺, Cu²⁺, NH₄⁺, brings about the marked change in swelling and dehydration characteristics. The swelling and dehydration characteristics of exchanged minerals are determined mainly by the interlayer cations exchanged and the difference of characteristics among ion exchanged Li-taeniolite or anhydrous Na-fluoro hectorite can be explained in terms of ionic size, charge number and hydration energy of interlayer cations.

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The “masking effect of alumina”, viz., the endothermic peak appeared at the melting point of 8-quinolinol (Hquin) in differential thermograms, disappeared when the sample was diluted with alumina, was reexamined.
Infrared spectra and X-ray diffraction data indicated that α -alumina does not react with Hquin and their mixture gives no “masking effect” as shown in Fig. 1. While, when Hquin was diluted with γ-alumina, the color of the mixture changed to yellow, and the “masking effect” was clearly recognized in DTA curves as shown in Fig.3. The absorption spectra of the solution obtained by extracting the mixture with chloroform, powder diffuse reflectance and infrared spectra of the solid mixture (Figs.2 and 4) showed the formation of Al (quin)₃.
Characteristic X-ray diffraction peaks of Al (quin)₃ did not appear. This fact su ggested that the Al (quin)₃ is formed only on the active surface of γ-alumina and the crystal does not grow to be detectable by X-ray diffraction.
By the use of this result, α and γ-alumina are conveniently distinguished with each other by the color change occurred when they are grinded with Hquin.

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A simple method of separation and determination of PO₄^3- in condensed phosphate and phosphate glass has been studied.
To 80 ml of the sampl e solution containing PO₄^3-, P₂O₇^4-, P₃O₁₀^5-, P₃O₉^3-, and (PO₃)_π^π-(sodium metaphosphate megtaapshosphate glass), 40ml of 5 NNH₄NO₃, 40 ml of 5 N HNO₃, and 17.5% amm onium molybdate solution were added and stirred for 20-30 sec. After the solution was allowed to stand for 5 min at 18-20°C, the precipitate formed by the reaction of PO₄^3- and molybdate ion was separated by glass filter (G 4) with suction and washed with 2% HNO₃, and then it was dissolved in 2.5% ammonia. The PO₄^3- separated from condensed phosphate was deter mined gravimetrically as Mg₂P₂O₇.
The experimental errors were within ± 0.0005g in the range of 0.05-4.175g as P₂O₅ of PO₄^3- without condensed phosphate. In the case of PO₄^3- in the presence of P₂O₇^4-, P₃O₁₀^5-, P₃O₉^3-, and (PO₃)_π^π- (O.1g as P₂O₅, respectively), the same errors were in the range of 0.01-0.125 g as P₂O₅ of PO₄^3-. The above procedure gave also the satisfactory results for the determination of PO₄^3- in alkali aluminophosphate glass containing 40 mol% of P₂O₅.

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It has been known that iron (III) reacts with 8-quinolinol to form a water insoluble complex. However, in the presence of sodium dodecyl sulfate (SDS) which is a most typical anionic surfactant, the precipitate of the complex is made water soluble above a critical micelle concentration (CMC) of SDS, while it is not made below the CMC. This phenomenon may be ascribed to the dissolution of the complex into the micelle of SDS, which is called the solubilization. The solubilized complex is stable for at least 2-3 days and has two absorption maxima at 460 and 580 nm. Absorbances keep nearly constant values over a high concentration region above the CMC of SDS.
This describes the spectro photometric method for the determination of iron (III) based on the coloration of the iron (III) 8-quinolinol complex solubilized in the SDS micelle. Recommended procedure is as follows: Take sample solution containing up to 500μg of iron (III). Add 5 ml of 0.6% 8-quinolinol solution, 1 ml of 0.625 mol/l SDS solution and 10 ml of distilled water. Adjust the pH to 5.0 with NH₄OH solution and CH₃COONH₄ solution and make up the final volume to 50 ml with distilled water. Measure the absorbances at 460 and 580 nm against a blank. Beer's law holds for 1-10 ppm of iron 010. The apparent molar extinction coefficients at 460 and 580 nm are 4.7 X 10³ and 3.6 x 10³, respectively.The sensitivities at 460 and 580 nm are 0.011 and 0.015 pg Fe (III)/cm² for log (I₀/I) = 0.001 level, respectively.
The interference of copper ( II ) can be eliminated by addin g KCN solution as a masking agent, and that of vanadium ( V ) by measuring the absorbance at 580 nm after the solution is finally made alkali.

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In order to increase the selectivity of the colorimetry of chromium and vanadium, the separation by means of anion exchange chromatography was tested. The column, φ O.8 X 5.0cm packing (50-100 mesh) Dowex 1 X 4 anion exchange resin was used for the separation of chromium. The solution containing chromium (VI), zinc (II ), cadmium (II ), iron (III) and reducing organic substances contained in industrial waste water was introduced into the column and then the substances other than chromium (VI) ware removed by washing the column with distilled water. Finally chromium (VI) was reduced to chromium (III) by hydroxylamine in the eluent and eluted. The concentration of sulfuric acid and hydroxylamine in the eluent were O.1 moll/and 0.001 mol/l respectively. For analyzing chromium (III) in the mixture of chromium (VI)and chromium (III), after removal of chromium (VI) it should be oxidized to chromium (VI)anion with the oxidant, e. g., sodium peroxide or hydrogen peroxide, before introducing it into the column. In terms of the pretreatment by using the acetate form resin column, chromium (VI) and chromium (III) can be determined separately in the solution whose con centration ranges from O.05 ppm to 0.5 ppm despite the presence of contaminants, which interfere with the colorimetric determination of chromium (VI) using diphenylcarbonohydrazide, in the original solution.
The separation of vanadium ( V) in the solution containing copper (II), cobalt (II) and etc. was made using the mixed solution of hydrochloric acid (2 mol/l) and hydroxylamine (0.2 mol/l)similarly to chromium (VI). In terms of the similar pretreatment vanadium could be determined precisely as far as 0.1 ppm by the colorimetry using 4 (2-pyridylazo) resorcinol despite the. presence of copper (II ), cobalt (II), nickel (II ) and etc in the original solution.

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In the ion-exchange chromatography of amino acids, it has been experienced that the resolu tion between threonine and serine become poor as the time for elution is shortened. Separation parameters to obtain a rapid separation of amino acids without decreasing the resolution were studied.
A spherical cation exchange resin of 9% cross-linked divinylbenzene particle diameter 11-14 μm was used as a column packing material, which was filled in the glass cloumn (i. d.: 9mm). The column efficiency of 0.05 mm was necessary for serine to be separated from threonine by 70% in terms of degree of separation [{(H₂-H₁)/H₂}x 100]. This value was obtained when maximum linear velocity of mobile phase was 0.14 cm/sec and the resin height was 13.5 cm. The resolution decrease in ninhydrin reaction tube was not negligible. When the retention time of threonine and serine was 12-14 minutes and i. d. of reaction tube was 0.5 mm, the degree of separation between them was varied 1% per one meter of tube length.
Under the optical conditions the separation of eighteen constituents of amino a cids in protein hydrolyzates completed within 60 minutes at low inlet column pressure of 10 kg/cm² by a single column.

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Hirate-machi, Kita-ku, Nagoya-shi 462 Japan The isobutane chemical ionization mass spectra of 19 alkylbenzene isomers have been determined using a quadrupole mass spectrometer at the source temperature of 75°C (Table 2).
The (M+ H)⁺ ion intensities of xylenes, ethyltoluenes and diethylbenzenes decreased in the order m->o->p-, while those of trimethylbenzenes decre4sed ii the order 1, 3, 5->1, 2, 4->1, 2, and those of tetramethylbenzenes decreased in the order 1, 2, 3, 5->1; 2, 3, 4->1, 2, 4, 5-. The order of (M+H)⁺ ion intensities of alkylbenzene isomers except trimethylbenzenes agreed with the order of the basisities.
The order of (M-H )⁺ ion intensities of the alkylbenzene isomers except trimethylbenzenes was opposite to that of (M+H)⁺ ion intensities.
The hyperconjugation effect due to the methyl substituents was observed in both proton and t-butyl addition reactions.

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Nitrophenyl p-toluenesulfonates were allowed to react with various nucleophilic reagents in liquid ammonia and the effects of the above reagents on the reaction courses were studied.
In the reactions of nitrophenyl p-toluenesulfonates with 1-hexanethiol, 1-dodecanethiol, benzenethiol and pentachlorobenzenethiol, thiolate anion attacks aryl carbon atom selectively, and the corresponding unsymmetrical sulfides are formed in high yield (Table 5).
On the other hand, in the reactions of 2, 4-dinitrophenyl p-toluenesulfonate [1] with hexylamine, cyclohexylamine, morpholine, piperidine, 2-methylpiperidine and 4-methylpiperidine, b oth C-O and S-O scission reactions occur (Table 7). But in the reactions of nitrophenyl p-toluenesulfonates, only S-O scission occurs, and no C-O scission takes place.
In the reactions of nitrophenyl p-toluenesulfonates with amines attack on sulfonyl sulfur is enhanced by the chlorine being substituted in phenolic moiety.
The reactivity of sulfonyl sulfur is markedly influence d by the steric factor of nucleophilic reagents.

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Tsurumi-ku, Yokohama-shi 230 Ja p a n The experimental conditions for the synthesis of benzonitrile by the reaction of α, α, α- trichlorotoluene with liquid ammonia have been carefully, scrutinized. When α, α, α- trichlora toluene was allowed to react with 17.5 fold mole of liq. NH₃ at 125°C for 2 hrs, benzonitrile was quantitively obtained. The addition of inorganic salts in this reaction system raised the yield of benzonitrile remarkably.
As the reaction pro ceeded, the yield of benzonitrile with respect to the consumed starting materials decreased owing to the formation of benzamidine hydrochloride. Ammonium chloride formed in the reaction accelerated the formation of benzamidine hydrochloride.

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Nitration of some benzene derivatives with copper (II) nitrate in acetic anhydride at 40°C was investigated. The yields of the nitro compounds are high in the case of benzene, toluene, ethylbenzene, anisole, and m-xylene, low in the case of o and p-xylene where acetoxylation of the benzene ring occurs, and zero in the case of chlorobenzene and nitrobenzene (Table 1). The above results and the orientation of the nitration are similar to those of nitration in nitric acid-acetic acid. An intermediate, 4-acetoxy-1, 2-dimethyl-1-nitro-2, 5-cyclohexadiene [1] was obtained by the reaction of them with o-xylene at low temperatures. The distribution of the decomposition products of [1] in acetic anhydride and acetonitrile (Table 4) elucidated the course of the formation of ring-acetoxylated products and the effects of addition of acetonitrile on this reaction (Table 2). These results suggested that acetyl nitrate is an active nitrating species in the reaction shown at the beginning.

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The rate of oxidation of 1-methylnaphthalene by cobalt (RI) acetate in acetic acid (Fig.1, 3)can be expessed as follows:
The first term in the equation works in the range of concentration less than 1.67 mol/1 H₂O and at 1.67 mol/l H₂O it works negligibly in comparison with the second term (Fig.4). These facts suggested that two kinds of active species should be considered for such a reactive substance as 1-methylnaphthalene. A synergetic effect was observed by the addition of cerium (IV) acetate to cobalt (III) acetate (Table 1).
The ρ value obtained from Hammett plots for the oxidation of substituted toluenes (Fig.6)by cobalt (III) acetate decreased with increasing Co (III) /Co_total at lower H₂O concentrations. This result can be interpreted in terms of the above equation, since the first term in this equation is more serious than the second one at lower Co (III) concentrations.

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A high speed liquid chromatographic technique was applied to analyze the oxidation products of 4-nitro-2-toluenesulfonate (NTS) by molecular oxygen in alkaline solution at 60°C.
The analysis was carried out under the following conditions, viz., Zipax-SAX column: 2.1 i.d. X 1m; temperature 40°C; pressure: 40 kg/cm²; mobile phase: mixture of 0.2 mol// NaClO₄ and water (gradient rate 1%/min, flow rate 0.4-0.5ml/min); detector: UV photometer (254 nm).
Following products were detected and identified by authentic samples: 4, 4'-dinitro-2, 2'bibenzyldisulfonate (NDS), 4, 4'-dinitro-2, 2'-stilbendisulfonate (NSS), m-nitrobenzenesulfonte (m-NBS), 2-formy1-5-nitrobenzenesulfonate (FNBS) and 4-nitro-2-sulfobe nzoate (NBS)The suggested oxidation schemes were as follows:
where, process (A) is a main reaction, and process ( B ) is a side reaction.
The rates of both processes increase with increasing alkaline con centration.

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Polypropylene resin composites, consisting of fine particles (the diameter was less than O.1μ)of sulfonated styrene/divinylbenzene copolymers which were prepared by the emulsion copolymerisation method and dispersing in a polypropylene matrix, were shaped into sheets. By treating the sheets with hot water, the heterogeneous cation exchange membranes of excellent electrical and mechanical properties, were obtained.
The effects of crosslinking of sulfonated styrene/divinylbenzene emulsion copolymers on the properties of the heterogeneous cation exchange membranes were investigated in detail. Hetero geneous cation exchange membranes, consisting of sulfonated styrene/divinylbenzene emulsion copolymers of high degree of crosslinking (divinylbenzene content: 15 wt% and 20 wt%) and dispersing in a polypropylene matrix, have very low specific resistance, although a cation (sodium ion) scarcely diffuses into those cation exchange resins which are composed of net-works of tightly crosslinked polymers with attached sulfonic acid group. It has been presumed that the cavities, which were formed among the particles of cation exchange resins and polypropylene matrix by the hot water treatment, and the surfaces of cation exchange resins played an important role in these heterogeneous cation exchange membranes.

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To find a mechanism of the anion-induced conformational transition of basic poly (α -amino acid) s in aqueous solution, the interaction of Cl^-, Br^-, I^-, ClO₄^- and SCN^- anions with poly (L-homoarginme) (PLHA), which has the same methylene length as poly (L-lysine)(PLL), was investigated in the neutral pH region by measuring the ORD, conductivity and viscosity and by observing the behavior of salting out.
PLHA was found to change its conformation from coil to helix at smaller concentration of the counter ions than PLL. The helix-content of the polymer increased in the order:Cl^-≤Br^-<I^-<ClO₄^- <SCN^-. The series is similar to that for the salting out of the polymer by NaCl, NaBr, NaI, NaClO₄ and NaSCN.
Independently, a sequence wa s determined to be Cl^--Br^-<I^- <ClO₄^- -SCN^- for the nonelectrostatic binding of the counter ions to the polymer by the use of deviation from the additivity law for conductivity. The sequence is also similar to those for the non-electrostatic binding to PLL and to other basic polyelectrolytes, and/or is similar to the sequence for lowering the reduced viscosity of PLHA.
From these results, it is conclud ed that the anion, which has a greater ability to break the water structure, can induce easily the coil to helix transition, which is caused by forming the ion-pair at the hydrophobic domain on the polymer surface. As guanidinium ion breaks the water structure more strongly than the ammonium ion, PLHA can change the conformation at smaller concentration of the anions than PLL.

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The reactions of bivalent transition metal acetylacetonates (M (acac)₂) with ethylene glycol (EG)were studied at 150°C. Mixed complexes of Co (II), Zn(II), and Ni (II). containing, both EG and acac were isolated, and characterized by the measurements of electronic, infrared as well as pmr spectra, X-ray diffraction and elemental analysis. The reaction of Co (acac)₂(H₂O)₂ or Co (acac)₃ with EG affords Co(acac)₂(eg), and the similar reaction with Zn (acac)₂ affords Zn (acac) (eg). These mixed complexes contain chelated structure with EG; however, Ni (acac)₂ (H₂O)₂ affords Ni ( acac)₂ (H₂O) (eg), which dose not contain chelated structure with EG, and no such mixed chelate is obtained in the case of Cu (acac)₂. On the basis of these results, the reaction mechanisms were discussed. The kinetics of transesterification reactions of dimethyl terephthalate. (DMT) with EG catalyzed by these isolated mixed complexes was studied at 140-160°C and. compared with the similar reaction catalyzed by metal acetylacetonaw. The catalytic activities of Co (acac)₂(eg) and Zn (acac) (eg) are higher than those of Co (acac)₂(H₂O)₂ and Zn(acac)₂. However the activity of Ni (acac)₂(H₂O)(eg) is inferior to th at of Ni (acac)₂(H₂O)₂.

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Methyl or halogen-substituted conjugated diene, e. g., isoprene (IP), 1, 3-pentadiene (PD), 2, 3-dimethylbutadiene (DMBD) or chloroprene (CP), was copolymerized with acrylonitrile (AN) at low temperatures in the presence of AlEtCl₂/VOCl₃ catalysts which gave alternating copolymers responsible for butadiene (BD) /AN copolymerizations.
Alternating copolymers were obtained with respect to copolymerizations under the specific conditions described above and these copolymers were characterized by copolymer compositions, IR and NMR analyses. The copolymerization rate was qualitatively increased in the following order CP<BD<IP≅ PD<DMBD with increasing values of ionization potential of diene monomers and producing order of Diels-Alder adduct in the present copolymerizations. In CP/AN copolymerization, the condition to give alternating copolymer was restricted within narrower limit than that of BD/AN, IP/AN, PD/AN or DMBD/AN copolymerization.
The microstructure of diene units of the resulting alternating c opolymers were all 1, 4-structure similarly to BD, on the other hand, DMBD and CP were presumably cis-1, 4-structure, IP/AN alternating copolymer showed stress-crystallization behavior like balata and was superior in mechanical strength to random copolymer having same composition. CP/AN alternating copolymer was resinous material.
However, the copolymer having AN (about 36 mol%) was elastic material which showed excellent mechanical properties and resistance to oil.

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The polymerization of methyl methacrylate (MMA) initiated by hydridocarbonyltris (triphenyl phosphine) rhodium ( I ) (hydrido Rh complex) -organic halides was studied. Effect of combina tion of organic halide with hydrido Rh complex on the polymerization was studied and found that only carbon tetrahalides have the polymerization ability. The polymerization of MMA in benzene initiated by the hydrido Rh complex and carbon tetrachloride (CCl₄) was kinetically investigated. In the lower concentration range of CCl₄ the rate of polymerization (R_p) was expressed by the following equation:
R_p= k[Hydrido Rh complex]^0.5·[CCl₄]^0.5· [MMA]^1.5
The apparent overall activation energy for the MMA polymerizatio n by these initiators was estimated to be 12.2 kcal/mol. The composition curve of the copolymerization of styrene with MMA in this system agrees with that of the radical polymerization and the polymerization of MMA is inhibited by p-benzoquinone and α, α-diphenyl-β-picrylhydrazyl. It was concluded on the basis of the above two facts that the polymerization of MMA in this system proceeds through a free-radical mechanism.

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The radiation-induced crosslinking of two commercial products KF and Kynar consisting of poly (vinylidene fluoride) (PVdF) has been investigated; KF and Kynar were the products polymerized in suspension at lower temperature and in emulsion at higher temperature, respectively. The two polymers differ one another in molecular structures and physical properties (Table 1 and Fig.1); particularly the concentrations of -CF₂-CF₂- bond and of branches in Kynar are higher than those in KF.
A marked difference in radiation effect betw een the two polymers was also observed; Kynar is more easily crosslinked than KF (Figs.2 and 3) and hydrogen fluoride formation from KF is less than that from Kynar (Figs.4 and 5).
KF differs from Kynar in efficiency of cross linking and in dehydrofluorination. This may be due to the irregularity of their molecular structures. It was suggested that dehydrofluorina tion of alkyl radical to form polyenyl radical was blocked by -CF₂-CF₂- bonds in polymer chain, and the probability of recombination of radicals increased to form crosslinks. The results of the radiation-induced crosslinking experiments on the copolymers of vinylidene fluoride and tetrafluoroethylene (Fig.6) were well interpreted in terms of the above suggestion.
As the branches in the polymer chain decrease the crystallinity and increase the molecular mobility of the segment in amorphous region, the crosslinking efficiency was assumed to be improved by branching.

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The most suitable conditions for the regeneration of 3 kinds of granular activated carbon, made from coal, which adsorbed contaminants from the pulp bleaching waste (Table 1, 2) were investigated. The spent carbon was heated in pure N₂ or in the mixture of N₂ and steam (10%). The pore distribution and the adsorptivity of the regenerated carbon were com pared with those of the virgin carbon.
The spent carbon a, b or c which adsorbed about 15 wt% of contaminants was not able to regenerated enough in N₂ (Fig.3-5). The suitable conditions for the regeneration of the carbon in steam are dependent on the kinds of virgin carbon. The spent carbon c was able to be regenerated at 680°C, but the spent carbon a was not able to be regenerated enough at lower temperatures than 750°C in steam (Fig.8-10). The suitable conditions are also dependent on the adsorbed amount of contaminants. The spent carbon d which adsorbed less contaminants than the spent carbon a was able to be regenerated at 700°C in steam (Fig.11).

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The catalytic activity and selectivity of aluminum phosphate containing sulfate ion for the dehydration of 1-butanol and the isomerization of 1-butene were investigated as a function of the content of sulfate ion. The sulfate ion showed a promoting effect when the content was low, but showed a poisoning effect when it was high. The selectivity was also affected remarkably by the addition of sulfate ion. The correlation between the catalytic activity and the acidic property was also discussed.

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The catalytic activity of various transition metal nitrides was examined for the reduction of NO with ammonia. Some metal nitrides, especially Fe₂N and Zn₃N₂, were more active than the corresponding metal oxides. The activity order was Fe₃N > Cu₃N > VN ≥ CrN ≥ Zn₃N₂ > > TiN, Mn₄N, the sequence being well coincided with that rep orted for the ammonia decomposition reaction. As for the selectivity of the reaction for N₂ or N₂O, Fe₂N and Zn₃N₂, which are interstitial nitrides, were found to produce N₂O very selectively while the other nitrides favored N₂. Brief discussion was presented concerning these results.

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The electrochemical reduction of the purine bases and their nucleosides in DMF has been investigated by polarography, cyclic voltammetry, and controlled-potential electrolysis. In neutral DMF solutions, these purine bases are initially reduced in a one-electron, diffusion- controlled process at a fairly negative potential to produce an unstable radical anion, which then takes a proton from parent purine to produce a free radical and an anion. The free radical is probably deactivated by fast dimerization to form dimer, or by chemical reaction which is followed by a further one-electron reduction. The reaction of anion with mercury at the electrode produced an oxidation wave.

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In the previous paper the binding behavior of optically active dansyl amino acids to bovine serum albumin (BSA) was reported. As a result of the study it was concluded that the dansyl amino acids bind to BSA making difference between their optical isomers, the binding constants of D-isomers are larger than that of L-isomers. In the present paper a study on the quenching of fluorescence of tryptophane residues in BSA by the binding of optically active dansyl amino acids was made. The quenching may be attributed to energy transfer from tryptophane residues to dansyl group bound to BSA. In the case of the binding of dansyl phenylalanine, higher degree of quenching was observed for D-isomer than for L-isomer. This result suggested that the differences in the binding constants of the optical isomers are due to the different interactions based on the stereospecific factors between the optical isomers and amino acid residues in the neighborhood of the binding sites of BSA.

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A so-called non-charged membrane such as cellulose acetate membrane has actually a small amount of charge, and the charge of the membrane varies with pH. The salt rejection of cellulose acetate membrane has a minimum value at pH 3, viz., at isoelectric point. The lower the annealing temperature of the cellulose acetate membrane, the larger the variation of the salt rejection with pH. When the concentration of NaCl in the feed solution is lower than 0.001 mol/l, the salt rejection of cellulose acetate membranes annealed at 80°C and of 6-nylon membranes decreases. This phenomenon would be caused by the circuit current occurred pronoucedly in piezodialysis.

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The liberation of hydrogen cyanide from sodium cyanide solution was studied both experi mentally and theoretically. The experiment was carried out by bubbling nitrogen through the solution in a contactor under the semi-batch operating condition at various temperatures, gas flow rates, pH values and concentrations of sodium cyanide in aqueous solutions. The observed liberation rate of hydrogen cyanide was compared with that predicted from eq. ( 6 )or eq. (12). The observed data were in satisfactory agreement with those evaluated from the proposed equations.

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