Synthesis of various types of zeolites has been reported using as a starting material silica sols, gels, silicates or silicate minerals, all of which are polymers of silicic acid. In this study Zeolite A was synthesized from ethyl orthosilicate which was probably a monomer at the beginning of hydrolysis. Optimum conditions of synthesis and factors which influence the formation of Zeolite A were examined.
Ethyl orthosilicate was directly hydrolyzed by sodium aluminate solution in the presence of excess sodium hydroxide. After ultrasonic and mechanical stirring for an hour at 70°C, the solution was kept in the air bath at 70°C under atmospheric pressure for 48-120 hours. Zeolite A with high purity and crystallinity was obtained in a good yield from the starting mixture with the composition of 2∼4.5 Na₂0. Al₂O₃0.5∼2SiO₃200∼400 H₂0. Present method was effective for the synthesis of Zeolite A in the lower molar ratios of SiO₃/Al₂O₃ as compared with the ordinary methods using silica or silicates. The species formed were also investigated by the optical, X-ray diffraction, DTA, TGA, IR and chemical methods.

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The absorption rates of methanol, acetone and methylacetate vapor through the monomole cular layers of, C16 and C18 straight chain alcohol on water surface were measured under lower pressure And at room temperature.
The initial rates are fitted to the first-order kinetics with respect to vapor concentration and the ratedeterming step is the process of passing through the monolayer film.
The apparent activation energies calculated from the rate constants at different temperatures are shown in Table 2. It was found that the apparent activation energies increase linearly with increasing cross sectional area of the permeant molecule.
From the analysis of these experimental results an empirical equation for the rate constant k, (cm/sec) of the permeant molecule as a function of cross sectional area is presented below:
kf=16.6066 x 10¹²(V_M/N_A) ^1/3 eXP {a(V_M/N_A)^2/3-b}exp[-{c(V_M/N_A)^2/3-d}/T]
where a, b, c or d are a fixed number for the film, V_M is the volume of the permeant molecule and N_A is Avogadro number.

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The catalytic action of alkylammonium carboxylates on hydrolyses of p-nitrophenyl acetate (PNPA), hexanoate (PNPH), and laurate (PAPL) was studied in various nonpolar solvents. The catalytic activity of the surfactants was enhanced by the micelle formation (Fig.1 and Table 1), and increased with increase in the number of ammonium ions in the surfactant molecule and of the hydrogen atoms attached to the ammonium ion (Fig.3). The catalytic activity depended also on the kinds of esters and solvents, increasing in the order of PNPA >PNPH >PNPL, and of heptane cyclohexane>benzene in both of the nonmicellar and micellar solutions (Table 2). The hydrolysis of PNPA was also studied in mixed surfactant and solvent systems (Fig.4). The results of hydrolysis obtained in cyclohexane and benzene solutions of dodecylammonium propionate were compared with that of mutarotation of 2, 3, 4, 6-tetra-O-methyl-α-o-glucose in the same surfactant solutions reported by Fendler et al. (Fig.5).

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An attempt has been made to estimate the critical micelle concentration (CMC) of a desired surfactant by investigating the reported CMC values of about 240 different surfactants in relation to their structures.
Surfactant molecules were divided into structural units, such as hydrophobic and hydrophilic groups, counter-ions, etc., to which appropriate quantities (scores) were given by the method of multivariate analysis under the assumption that "a CMC value can be expressed by the linear combination of the score given to each structural unit ". Structural, units have been quantified by resolving a set of simultaneous equations with a computer and the results are summarized in Table 2. Under the above assumption, the CMC value of a surfactant has been estimated by using the scores shown in Table 2. Correlation coefficient ρAa between estimated and observed values is O.98 as a whole, which indicates that the way of estimating a CMC value, proposed in the present paper, is useful in practice with reasonable accuracy, especially, for surfactants having a relatively simple molecular structure.

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The kinetics of the reaction of N, N-disubstituted amino diphenyl phosphine (Ph₂PNR₂) with ethylene carbonate (EC) have been studied to elucidate the reaction mechanism of P-N compounds. The reaction followed the 2 nd order kinetics.
v=k₂[Ph₂PNR₂][EC]
Taft's equation between the rate constants and the substituents on the nitrogen atoms of Ph2PNR2 was applicable to this reaction, and p* and s values were determimed to be -1.04 and 0.78, respectively. The large negative p* and comparably small s values were characteristic of this reaction compared with those of the reaction between N, N-disubstituted ethylene phosphorus amide and acetic anhydride (-0.194 and 1.0, respectively).
These results seem to suggest that the nucleophilic attack by the nitrogen atom of Ph₂PNR₂ on the carbonyl carbon atom is the rate determing step and the interaction of the phoshorus atom with carbonyl oxygen or ester oxygen atom does not play an important role in the reaction.

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The reaction mechanism for the NO+NH₃ was studied by means of closed circulation system. The products were N₂ and N₂0, under the conditions studied. Isotopically labelled ammonia, NH₃, was also used in order to clarify nitogen-atom sources in the products. It was concluded that the reaction proceeds through the following successive steps.
This mechanism was led from the following results.
1) The selectivity to N₂, defined as N₂/(N₂+N₂0) in the gas phase, was high in the initial stage of reaction and then approached a constant value of O.67 under the conditions studied.(2) The main product in nitrogen was NN, while dinitrogen oxide was N₂0.(3) The redox scheme which was valid in the catalytic reduction of NO with H₂ or CO was found to be unappropriate.
The reaction mechanism (1) and (2) proposed here, compared with our proceeding studies concerning NO+H₂ or NO+CO reaction, well explained the characteristics of NO+NH₃ reaction, that is, selective reduction in a practical system containing significant amount of oxygen.

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Oxidation of CO with ¹⁸O₂ on Bi, Ca, Ni and La molybdate catalysts was investigated by measuring the ¹⁸O concentration in CO, . As shown in Table 1, the distribution of ¹⁸O concentration was in good agreement with the value calculated on the assumption that the isotopic mixing is very rapid. It is suggested that the ¹⁸O concentration in the products is close to that on the catalyst surface. Change in ¹⁸O concentration was plotted against the amount of CO₂ formed as shown in Fig.1 and 2. In the case of β, γ-Bi-Mo-0 and La-Mo-O, increase of ¹⁸O concentration was slow whereas that of a-Bi-Mo-O, CaMoO₄ and NiMoO₄ was rather rapid. It is likely that the lattice oxygen in the former group is mobile and is immobile in the latter. The former group has a layered-type structure with (Bi₂O₂²⁺), or (La₂O₂²⁺), layer. This layer contains lattice oxygen that has no bonding with Mo²⁺. The member of the latter group has no such lattice oxygen. The mobility of lattice oxygen is attributed to the layer structure like (Bi₂O₂²⁺), layer.

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Experiments on the methanol synthesis from carbon dioxide and hydrogen were carried out under the following conditions; catalysts: ZnO.Cr₂O₂.SiO₂.Al₂O₃, pressure: 40∼100 kg/cm², temperature: 260∼350°C, mole ratio for H₂/CO₂ in the feed gas: 2.06∼8.34, space velocity: 5 x 1O²∼5 X 1O²hr^-1
According to the experimental results, the degree of conversion of carbon dioxide to methanol increases with increasing pressure and hydrogen content in the feed gas. On the other hand, the conversion reaches a maximum at a given temperature and decreases with rising temperature. The formation of carbon monoxide occurs as a side reaction. This reaction is accelerated by the increase in reaction temperature and hydrogen content in the feed gas whlie it is only slightly accelerated by the increase in total pressure.
Results of the kinetic treatment of the experimental data showed that the overall reaction consists of the following two parallel reactions;
The initial rates of these reactions were found to be expressed by
The Arrhenius plots for k' and km give activation energies of 42 kcal/mol and 25.5 kcal/mol, again respectively.

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The reaction which occurs in the process of thermal decomposition of Cd(OH)₂ in the CO₂ atmosphere was studied by means of DTA. X-ray diffraction pattern, TG, DSC, IR spectra and specific surface area were as well measured.
A broad endothermic peak (240∼340°C) and a narrow exothermic peak were observed on a micro-DTA curve. By the analysis of X-ray diffraction pattern of this process, it was recognized that the dehydration of Cd(OH)₂ and the formation of CdCO₃ proceeded within this temperature range. Furthermore, an endothermic peak around 468°C was considered to appear by the decomposition of CdCO₃. Endothermic peak was observed only at 244°C and 370°C on a micro-DTA. By the result of X-ray diffractometric analysis, it was considered that the decomposition of Cd(OH)₂, and the formation of CdCO₃ took place under the same process as micro-DTA.

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The formation of graphite bisulfate lamellar compound on pyrolytic graphite electrode annealed at 3000°C was studied at 25°C in 0.001, 0.01, O.1, 1, 5, 10 and 18 mol/l sulfuric acid electrolytes by means of galvanostatic, cyclic voltammetric and X-ray diffractometric techniques. The following results were obtained:
(1) The anodic oxidation of graphite electrode were classified to two different reactions,
a) the evolution of oxygen on the electrode surface at lower sulfuric acid concentration and
b) the formation of lamellar compound on the electrode at higher sulfuric acid concentration. The oxidation potential shifted to noble direction by the increase of sulfuric acid concentration for the former reaction (a), but to basic direction for the latter reaction (b). These reactions competed in the 0.1∼1 mol/l sulfuric acid electrolyte.
(2) The formation of lamellar compound was correlated to the sulfuric acid concentration. Just after oxidation, 10 th∼20 th stage, 3 rd stage and 1 st∼2 nd stage of lamellar compound were formed with 1, 5 and 10 mol/l sulfuric acid electrolyte, respectively.

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The mechanism for the dispersion of metallic magnesium in the molten salts was studied. Magnesium particles of O.4 mm diameter were dispersed in the lower parts of the molten salts by agitating mixtures of magnesium and MgCl₂-KCl at 700∼900°C. The increase of magnesium oxide concentration in the molten salts augmented both the amount of magnesium dispersed and the homogeneity of magnesium particles by decreased the mean diameters of particles. The dispersed magnesium particles didn't coalesce each other and were not deformed even by the solidification of the molten salts. It was suggested that the stabilization of the dispersed magnesium particles was caused with magnesium suboxide films through the reaction of magnesium oxide with magnesium metal.

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Graphite fluoride is usually prepared by the direct fluorination of natural graphite under the fluorine pressures of 100 to 200 mmHg in the temperature range from 500 to 600°C. At the fluorine pressures below 50 mmHg, the decomposition of graphite fluoride took place appreciably before the completion of fluorination ; C : F=1 : 1 (Fig. 1) . To elucidate the phenomenon described above, the decomposition reaction of graphite fluoride was studied by DTA, TG and gas analysis in an inert gas atmosphere and in vacuum.
Under the condition of high-fluorine pressure, formation and crystallization of graphite fluoride proceeds rapidly so that the decomposition hardly occures. On the other hand, under the low-fluorine pressure, decomposition of graphite fluoride occurs appreciably due to the slow rate of crystallization. The decomposition can be accelerated by the additional effects ; 1) decrease of fluorine concentration at the reaction interface by the reaction of fluorine with fluorocarbon radicals, by dilution with the produced gases, 2) the local tempera-ture increase caused by the exothermic reaction of the decomposition.
The decomposition of graphite fluoride was inhibited in vacuum. This result suggested the rapid diffusion of reactive fluorocarbon radicals produced by the cleavage of C-C bonds out of the system in vacuum compared with that in the atmospheric pressure.

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Sodium thiosulfate was oxidized at 20∼75°C with HO, and NaClO in the solution having a total sulfur concentration of 0.04 mol-S/l. The oxidation of intermediate tri- and tetrathionates was also examined to elucidate the mechanism of oxidation of thiosulfate.
H₂O^2- Oxidation: Competitive reactions took place to form tri- and tetrathionates. At pH 4, the reactions (3)∼(5) proceeded so slowly that the reaction products were only tri- and tetrathionates formed by the reactions (1) and (2).
In the presence of Fe²⁺, however, thiosulfate was completely oxidized to sulfate even at such a low pH. At higher pHs, it was found that the oxidation of tri- and tetrathionates to form sulfate took place beside the direct oxidation of thiosulfate to sulfate.
NaClO Oxidation: Following reactions took place to produce tri- and tetrathionates, which were finally oxidized to sulfate in all of the pH region tested.

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The separations and determinations of formic, acetic, glycolic and lactic acids were carried out by means of a liquid chromatograph equipped with a heat- of -adsorption detector.
The mixture of the above four acids was separated from each other under the following conditions; separation column: 8 mm i. d. x 1550 mm long glass column packed with an anionexchange resin, AG1-X 8 (250∼400 mesh of wet base), sample size: 1 ml, eluent: 0.1 N HCl, flow rate: O.15 ml/min, separation column temperature: 45°C and detection column temperature: 35°C. The determination of each acid was successfully carried out despite the incomplete separations of glycolic and lactic acids. The calibration curves of the four organic acids were drawn by the measurement of the peak areas. Within the sensitivity (±3/1000°C) of the heatof -adsorption detector, the linear calibration curves were obtained in the concentration ranges: 0∼1.8, 0∼0.3, 0∼2.4 and 0∼1.5 mg/ml for formic, acetic, glycolic and lactic acids, respectively.
This determination method was applied to kraft pulp cooking liquor and satisfactory results were obtained except for glycolic acid. It was also applied to other pulp waste water.

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The stable conformations of 1-naphthaldehyde and 2-naphthaldehyde are investigated by NMR measurements with paramagnetic reagent technique. The stabilities of those conformers are in agreement with the results predicted by Fukui theory. The UV-spectra of these compound are also measured in several solvents.
The observed excitation energies and their absorption coefficients are compared with the results calculated by the semiempirical SCF-limited CI method.

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Air containing vinyl chloride (VC) of less than 1 x 1O⁴ ppm was irradiated by mercury lamp and sun light at room temperature. More than 99% of VC disappeared within 15 min by the irradiation with 100 W high pressure mercury lamp. The conversion of VC increased with the increase in the irradiation time. The initial rate of the decomposition increased with the decrease in the concentration of VC in the air, and the reaction was remarkably accelerated by the irradiation with UV light of shorter wavelength. The reaction also took place by the sun light irradiation, and even in winter, 50% of VC disappeared under outdoor exposure of two days. The effect of reaction temperature on the initial rate was negligible. As one of the decomposition products, chloroacetaldehyde was detected in the irradiated gas of short irradiation time. Hydrogen chloride and carbon dioxide were found in the sample of long irradiation time of 30 min. Air containing no toxic components could be obtained by washing the irradiated gas with an alkaline solution. On the basis of these results, a mechanism of the photo-decomposition of VC in the air under UV irradiation was proposed.

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The radical addition reaction of alkylbenzenes [1], X-C₆H₄-CHRR', (toluene, p-xylene, mxylene, o-xylene, p-chlorotoluene, p-methoxytoluene, ethylbenzene, cumene) to chlorotrifluoroethylene in the presence of di-t-butyl peroxide gave corresponding 1: 1 adducts [2] X-C₆H₄- CRR/CF, CHClF, together with 1: 2 adducts [3], X-₆H₄-CRR'(CF₂CClF)₂H, and cycloadducts [5]
. Dehydrofluorination of [2] with potassium hydroxide in dioxane gave the corresponding styrene derivatives [6], whereas the reaction with potassium hydroxide in alcohol gave the acetals of α-fluorocinnamaldehydes. Photo-halogenation and hydrolysis of the adducts were also carried out.

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NMR spectra of 7-oxa-2-norbornene derivatives obtained by the Diels-Alder reaction of furan or 2-methylfuran with acrylonitrile or methyl acrylate were studied. In ¹H-NMR spectrometry, the assignment of the signals was carried out i) by the comparison of each signal with those of corresponding norbornene derivatives, ii) by the use of spin decoupling, and iii) by the simulation of spectra employing the spectral parameters estimated. The 'H chemical shifts and the coupling constants are summerized in Table 1 and 2.
The ¹³C-NMR spectra were measured by noise-decoupled ¹³C FT method in CCl₄. The assingnment of their signals was carried out i) by comparing them with the those of chemical shifts of norbornene derivatives (Table 3), ii) by applying additivity rule of chemical shift, and iii) by using off-resonance proton decoupled spectra. The ¹³C-NMR chemical shifts observed are listed in Table 4 and 5.
Both ¹H and ¹³C-NMR spectra of 7-oxa-2-norbornene derivative are similar to those of corresponding norbornene derivatives. But each signal of the former is considerably separated by the deshielding effect of oxygen. Therefore, the ratio of stereoisomers present in the reaction mixture may be estimated by the signal intensity of NMR spectra.

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Several nickel isonitrile complexes were synthesized by the reaction of bis (1, 5-cyclooctadiene) nickel, (Ni(COD)₂), with alkyl isocyanides, (RNC). The reaction is shown as follows.
Bis (alkyl isocyanide) nickel, (Ni (RNC) ₂), and tetrakis (alkyl isocyanide) nickel, (Ni (RNC)₄), were prepared by mixing Ni (COD) ₂ and RNC at room temperature. Ni (RNC)₄ and Ni (RNC)₂ were also obtained by treatment of Ni (RNC) ₂ with 2 RNC, and by that of Ni (RNC)₄ with Ni (COD) ₂, respectively. (Alkyl isocyanide) (π-allyl) nickelchloride, (πC₃H₅NiCl(RNC)), was prepared by the reaction of Ni (COD)₂, allyl chloride and RNC.
The structure of Ni (RNC)₂ was examined by IR, NMR spectra and molecular weight measurement to confirm a polynuclear complex having RNC bridge bonding.
Ni (RNC)₂ and Ni(RNC)₄ catalyzed the oligomerization of butadiene and π-C₃H₅NiCl(RNC) acted as a catalyzer for the polymerization of the diene.

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In the course of our investigation on specificity of cyclization reaction by means of polypho-sphoric acid, it was found that 2-benzoyl-3, 4, 5, 6-tetrachlorobenzoic acid [1] and 2-benzoyl-3, 6-dichlorobenzoic acid [4] gave 3, 3'-oxydi (3-phenyl-4, 5, 6, 7-tetrachlorophthalide) [2] and 3, 3'-oxydi (3-phenyl-4, 7-dichlorophthalide) [5] in addition to 1, 2, 3, 4-tetrachloroanthraquinone [3] and 1, 4-dichloroanthraquinone [6], respectively. The structures of [2] and [5] were determined on the basis of their IR, UV and Mass spectra and chemical behaviors.

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The effects of reaction temperature and mercury catalysis on the isomer distribution in the monosulfonation of the title compounds have been studied in 90% sulfuric acid at various temperatures. The isomer ratios were determined by ultraviolet spectrophotometric analysis. The degree of ortho-substitution in the sulfonation of phenol, anisole, and phenetole was 45, 31 and 25% at 20°C for 1 hr; 35, 21 and 17% at 60°C; 14, 10 and 7% at 100°C, respectively. Ortho-substitution decreased with increasing size of the substituents. Additon of mercuric chloride as a catalyst resulted in the increase of the total yield of the sulfonation products as well as the degree of ortho-substitution.

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Ethylbenzene-4-sulfonic acid [3] was prepared by monosulfonation of ethylbenzene [D], while ethylbenzene-2-sulfonic acid [2] was obtained from o-ethylaniline[6] by the Gattermann reaction (sulfinic acid [7]), chlorination (sulfonyl chloride [8]) and hydrolysis. Both sulfonic acids were finally purified through their anilinium salts followed by the decomposition in potassium carbonate solution. They were characterized by the IR and NMR spectra, and by their sulfonamides and S-benzylthiouronium salts.4-Aminoethylbenzene-2-sulfonic acid [1O] was prepared by the reduction of the corresponding nitro compound, while 3-isomer [l2] was obtained by the baking process from p-ethylaniline [11]. The NMR chemical shifts for the methylene protons of these sulfonic acids are as followes; [2]: δ-1.62, [3]:δ -2.25, [l0]:δ-1.85, [l2]:δ -2.15 ppm (from internal H₂0 in D₂0).
In the sulfonation of [l] with 98% sulfuric acid, the ratio of the products, [2]/[3], decreases from 32/68 at 20°C to 6/94 at 120°C. Sulfonation of 4-nitroethylbenzene [5] was carried out in 20% oleum giving 2-sulfonic acid [9] as a main product independent of temperature or presence of mercury (II) chloride.
In the sulfonation of [11], the ratio of the products, [l0]/[12], is 79/21 at 20°C, but it gradually decreases to 60/40 at 140°C. The above ratio is not affected by mercury (II) chloride but the yield increases.

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Amido-bonded disaccharides, composed of amino sugars (benzyl 2-amino-2-deoxy-a-D-glucoand -α-D-mannopyranosides, and methyl 6-amino-6-deoxy-α-D-glucopyranoside) and uronic acids, were synthesized. The desired compounds were obtained in 37-75% yields by the dicyclohexylcarbodiimide method in the case of 1, 2: 3, 4-di-O-isopropylidene-α-D-galactopyranuronic acid, and by the direct addition method in the case of 1, 2-0-isopropylidene-α-Dglucofuranurono-6, 3-lactone. NMR Spectra of 0-acetyl derivatives of these disaccharides show the additive patterns of the corresponding monosaccharide derivatives.
By the similar methods, chloramphenicol base was acylated with the above uronic acids and benzyl /β-D-mannofuranosidurono-6, 3-lactone. However, these compounds show no biological activities.

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Reaction of erythro-N-benozoy1-β-phenylserine methyl ester [1] with phosgene gave 0- chloroformyl compound [2] as an unstable oily substance. The solution of this compound [2] in ethyl acetate was kept on standing for several months at room temperature to give threo-0-benzoyl derivative [3] as a result of inversion of the configuration on β-carbon atom. Heating of [2] on water-bath for a few minutes, however, provided mainly erythro-N-benzoyl-β-chloro-β-phenylalanine methyl ester [4] with retention of the β-configuration.
While, a diastereomeric threo-0-chloroformyl derivative [5] gave a mixture of trans-oxazolidone compound [6] and threo-chloro derivative [7] without any configurational change.
Reaction from erythro compound [2] to threo one [3] was discussed and following route was proposed erythro-N-benzoyl ester [2] →trans-oxazoline derivative [8] → threo-0-benzoyl ester [3].

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A study on the kinetics of the transesterification of dimethylterephthalate with ethyleneglycol catalyzed by metal-acetylacetonato complexes was made at 140∼160°C. The rate of the transesterification, RD could be expressed as follows
The rate constants determined from (2) was dependent on the metal in the catalyst and in the following order. Pb^2+>Zn>Mn²⁺>Co²⁺>Fe>Ni²⁺ =Cu²⁺ Cr", Sn4+.0, smilarly apparent activation energies increased in the following order: Mn²⁺Pb²⁺<Co²⁺<Zn²⁺<Ni²⁺<Cu²⁺.

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The effects of polymerization condition on the radical copolymerization of 2-chloroethyl vinyl ether with maleic anhydride and some properties of the alternative copolymer obtained were investigated. The activity of initiators for this copolymerization is in the order: lauroyl peroxide=azobisisobutyronitrile> benzoyl peroxide. As to the kind of solvent, benzene is the most adequate, and water and oxygen inhibit the copolymerization. The apparent activation energy determined from the rates of the copolymerization during the initial period at 40°, 50° and 60°C is 19.5 kcal/mol. The copolymer is easily soluble in acetone, dimethyl sulfoxide, N, N-dimethylformamide and dilute alkaline solution, but insolube in ether and benzene, and gradually soluble in dioxane, ethanol and water at room temperature. The intrinsic viscosity of copolymer is O.164 in acetone at 30°C. The release of HCl from chloroethyl group of the copolymer occurs when heating it in its alkaline solution. Two exothermic peaks, which accomponied by the release of HCl from the copolymer, appear at 300° and 400°C in the thermal analyses.

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Radical copolymerizations of cis-tetraamminebis (methacrylato) cobalt perchlorate, Co(MAA)₂, with methacrylic acid (MAA) were carried out in an aqueous medium which was adjusted to pH 3 at 30°C. It was found that Co(MAA)₂ copolymerizes with MAA but does not singly homo-polymerize. Relating to the reactivity of pentaamminemethacrylatocobalt (lff) perchlorate, Co (MAA), the reactivity of Co(MAA)₂ was discussed in terms of the data of monomer reactivity ratio, Q-e values and rate of copolymerization. It was also found that this type of metal-complex monomer, different from Co (MAA), can not exert significant influence on the microtacticity of the copolymers. The possible mechanism of the chain propagation was discussed.

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When maleic anhydride was added to Co (acac)₃-AlEt₃ catalyst system, which is known as a dimerization catalyst of butadiene, an active polymerization catalyst for butadiene was obtained. The investigation of the active species of this catalyst was carried out.
It was found that (π-cyclooctenyl) (π-1, 5-cylooctadiene) Co-maleic anhydride catalyst system gives polybutadiene of the same structure as that obtained with above three component catalyst system, Co (acac)₃-AlEt₃-maleic anhydride.
A new complex of cobalt coordinated with maleic anhydride and 1, 5-cyclooctadiene was obtained by the reaction of (π-cyclooctenyl) (π-1, 5-cyclooctadiene)Co with maleic anhydride. Polybutadiene of the same structure was also produced by this complex catalyst. Thus the active species of the catalyst was considered to be a cobalt complex with maleic anhydride as a ligand.
Dienophile compounds as well as maleic anhydride are effcetive for a ligand of cobalt complex to bring about the polymerization of butadiene. Crystalline polybutadiene with 1, 2- unit contents more than 90% is obtained when dialkyl maleate or fumarate is used as a dienophile compound.

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Isoprene was found to polymerize with ternary catalyst system of Co (acac)₃-AlEt₃-dienophile compound or with binary catalyst system of (π-cyclooctenyl) (π-1, 5-cyclooctadiene) Co-dienophile compound. Liquid cis-1, 4-polyisoprene was obtained when dialkyl fumarate or maleate was used as a dienophile Dompound in the catalyst system. cis-1, 4-polymerization content in this polymer is more than 90% and its molecular weight is about 8000.
The effects of alkyl group in dialkyl fumarate, temperature, solvent and hydrogen gas on isoprene polymerization with (π-cyclooctenyl) (π-1, 5-cyclooctadiene) Co-dialkyl fumarate catalyst system were examined.

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The temperature dependence of radiation-induced crosslinking of poly (vinylidene fluoride) (PVdF) was investigated in connection with temperature dependence of molecular motion measured with wide-line NMR.
The G values for crosslinking (C) and main-chain scission (S) were estimated from experimental determination of the gel fraction formed by Co-60 r-irradiation at various temperatures in vacuo.
The gel formation increases with increasing irradiation temperature (Fig.1), however, the activation energies of crosslinking and main-chain scission changed at 50°C (Fig.2): The G (C) increases with an activation energy of 1.36 kcal/mol below 50°C. Above 50°C, the activation energy decreased to 0.28 kcal/mol. The G (S) is independent of temperature below 50°C, while above 50°C, the G (S) decreases with an activation energy of -2.3 kcal/mol.
The gel fraction increases by post-irradiation-annealing, and the increment of the gel fraction increases with increasing annealing temperature (Fig.3). This agreed with the behavior of radical decay in irradiated PVdF (Fig.4).
The results of NMR (Figs.5, 6 and 7) suggested that at above 50°C the endlinking reactions of -CH₂-CF₂ and -CF₂ -CH₂ with -CH₂-CF-CH₂- and -CF₂ -CH-CF₂ - were accelerated by microBrownian motion in the amorphous regions.

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Water-soluble cationic polymers were prepared by the amination of the poly (vinyl alcohol) etherified with epichlorohydrin. In order to see the flocculating action of these polymers the kaolin suspension was used. The flocculation effect was studied by observing the supernatant suspension concentration in jar test, the sedimentation rate and sedimentation volume by the test tube.
When PVA (0.5 g) was treated with epichlorohydrin (4 ml) in 20% H₂SO₄ solution (6 ml) at 30°C for 1 hour, the degree of etherification was about 5 mol %. The cationic polymers having excellent flocculating action were obtained, when etherified PVA (M. W.8.6 x 1O^2-) was continuously aminated with 2-6 mole polyethylenepolyamine (to PVA) at 40∼80°C for 1∼4 hours. Cationic polymers which were obtained by the amination with diethylenetriamine, triethylenetetramine and tetraethylenepentamine under most suitable condition gave the same flocculation effect. The maximum rate of sedimentation was 6.3 cm/min, when the amount of polymers was 0.006% on kaolin. The relation between the flocculation effect and the expansion of cationic polymer in aqueous solution was discussed.

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Poly (vinyl chloride) resin used for electric wires was thermally decomposed at 500°C to obtain the crude oil in 20∼25% yield. This oil was mixed with various metal hydroxides and carbonized at 550 or 650°C. After washing the carbonized residue, active carbons were obtained in 0.9∼7.6% yield.
Adsorptive capacities of these active carbons toward the solutions of iodine, Methylene Blue, caramel, ligninsulfonate and humate were measured in terms of standard methods. From the correlation between adsorptive capacities (Table 2) and pore-size distributions (Fig.1∼3) of these active carbons, radii of the effective pores for adsorptions were found to be less than 15Å for iodine and Methylene Blue, less than 100Å for caramel and 100∼500Å for ligninsulfonate and humate.

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In the adsorption of organic substances in wastewater on activated carbon, their molecular weights play the most important role. An assumption was made that when high molecular weight substances are concurrently adsorbed with low molecular weight substances on micropores of activated carbon, the former substances tend to decrease the rates and amounts of adsorption of organic substances on activated carbon.
If this assumption is correct the rates and amounts of adsorption may increase by removing the high molecular weight substances from wastewater.
By using commercial ultrafiltration membranes, which fractionate organic substances (COD) according to their nominal molecular weight, five wastewaters and two activated carbons, the rates and amounts of adsorption were tested.
The experimental results showed that the rate and the amount of adsorption on the activated carbons increase when organic substances with nominal molecular weight of more than 10000 are removed. It was further found by analyzing the results that the components with a nominal molecular weight of more than 30000, particularly interfere with the adsorption.

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The sulfation of metal oxides and the thermal regeneration of metal sulfates to oxides were studied for the purpose to obtain suitable dry absorbents to remove SOW. The metal oxides used ware CuO, Mn₂O₃, Co₃O₄, NiO, Fe₂O₃, Al₂O₃, Cr₂O³, MgO, ZnO and etc., prepared from metal salts (sulfate or nitrate) and alkali (NaOH, Na, CO, or NH, aq.). The experiments were carried out using a thermobalance under atmospheric pressure and at 25 to 800°C (mainly 350 to 650°C) together with X-ray diffraction analysis. Inlet gases were 0.2-0.5% SO₂0.1%-1% O₂0-4 % H₂O-N₂, SO₃N₂, SO₂N₂ and etc., and the total gas flow rate was 600 Ncms/min for 100-200 mg of metal oxides. Also, the regeneration was studied in N2 or air stream at 650-800°C.
The following compositions (A-D) of metal oxides prepared from metal sulfates and NaOH at 70-100°C were selected to be suitable for sulfation and regeneration. And, it was elucidated that CuO, Mn₂O₃ and Co₃O₄ act as absorbents for SOx, Fe₂O₃ and NaOH as an oxidative catalyst for SO₂ to SO₂ (sulfation rate with SO₂ is higher than with SO₂), and Al₂O₃ as a carrier.

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Humic acid prepared through the oxidation of Miike bituminous coal by 5 N nitric acid (100±5°C, 3 hr) and chars prepared by carbonization of humic acid at 200, 300, 400, 550, 600, 700 and 800°C for 1 hr in an inert atmospher were used as adsorbent for methylmercury chloride (MMC).
After shaking 100 ml of 1 ppm MMC aqueous solution with O.1 g of adsorbents for 24 hr, the residual concentration of MMC in the supernatant solution was determined. The residual concentration of MMC increased with the elevation of carbonization temperature up to 400°C and decreased above 400°C (Fig.1). The presence of HCl or NaCl increased the residual concentration of MMC in the case of humic acid, char prepared at 200°C and Amberlite CG-50 (Fig.2, 3) On the other hand, in the case of chars prepared at 600 and 800°C and activated carbon, the presence of HCl or NaCl reduced the residual concentration of MMC (Fig.4, 5). From these results, it was concluded that humic acid and char prepared at below 400°C adsorb CH, Hg+ ion by ion exchange reaction, but char prepared at above 400°C adsorbs MMC as molecule. It was also found that the influence of Cl on the adsorption of MMC was more

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The iodide electrode was found to be responsive to diamminetetrakis (isothiocyanato) chromate (III) ion (R-ate ion) and to obey Nernst's equation in the region from 10^-5 to 10^-1 mol/l. This response seems to result from the formation of silver diamminetetrakis(isothiocyanato)chromate (III) membrane on the surface of the silver iodide electrode. This R-ate ion responsive electrode was used to measure the solubilities of R-ate salts of metals, amines, and surfactants. Solubilities obtained by this method agreed to those obtained by spectroscopic methods.

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Multivalent ions could be determined by a sim indirect method with the same or higher precis-wit Lhan that cbtainable with multivalent ion selective electrodes. The operation was as follows: A reacting ion selective electrode, whose response slope being S₁, was immersed into a monovalent reacting ion solution with a concentration of C_M and a volume of vm, and the electrode potential was measured. Next, a certain volume, V of n-valent ion solution to be determined, which quantitatively gave a precipitate with the reacting ion, was added to the reacting ion solution. When the potential change e, brought about by adding n-valent ion, measured, a concentration, Cz, could be calculated by the following equation:
The precision of this method was discussed in terms of the potentiometric precision as well as the volumetric precision (Figs.1 and 2). Theoretical calculation showed that the indirect method gave higher analytical' 'precision in a certain range of concentration than that given by thd'-'direct calibration curv-e mothod, when the potentiometric precision of multivalent ion selective electrodes was low. The above discussion was confirmed by determining sulfide ion by using a silver sulfide solid-state electrode and silver ion as a reacting ion.

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The surface state of iron species being dipped in the aqueous solutions of various pH was studied by X-ray photoelectron spectroscopy. The species treated in the solution with the pH from 4 to 9 had rather higher peak intensity of oxygen in hydroxyl group but had extremely weak peak intensity of metallic iron, compared with those obtained by the specimen treated in the solution with the pH above 9.
The presence of oxine showed no remarkable variations in the intensity ratio of two peaks at above pH 4. It was considered that this fact was attributed to the local formation film containing oxine on the surface.

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The reactions of 9, 9'-bifluorenylidene[1] with active methylene compounds [2], e. g., fluorene [2a], 2-methylfluorene [2b], 2-ethylfluorene [2c], indene [2d]p, malonitrile [2e], phenylacetonitrile [2f], ethyl cyanoacetate [2g], 2-butanone [2h], propiophenone [2i], 2-pentanone [2j], butyrophenone [2k] and 4-phenyl-2-butanone [2l], catalysed by KOH or Triton B in DMF or DMSO at room temperature give the corresponding 9-substituted 9, 9'-bifluorene derivatives [3] Michael type adducts, in good yields.

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The decomposition of tetramethyl-2-tetrazene [1] has been studied kinetically in the presence of benzyl halides, such as benzyl chloride (BC), benzyl bromide (BB), and benzyl iodide (BI) in the temperature range from 20 to 40°C in N, N-dimethylformamide (DMF). From the effect of halogen on the activation parameters for the reaction of [1] with benzyl halides, it was found that the value of ΔG‡ is scarcely influenced by halogens, and that the values of ΔH‡ (8.24 to 14.3 kcal/mol) and ΔS‡ (-33.8 to -42.3 cal/°K) are characteristic for those A5 reaction with, 2 mechanism. In additionClreacts with benzyl halides to form tetrame- thylhydrazine [2], N, N-dimethylbenzylamine [3] and dimethylamine [4]. Tetramethylhydrazine radical cation [5] was also detected by ESR.

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In the course of the investigation of the flame retardant for cellulosic materials, such as fabrics, plastices and etc., it was found that cellulose acquired durable flame retardancy by treating it with an aqueous solution containing 15% of orthophoshoric acid, 15% of urea, and 10∼20% of dicyandiamide, and that the treated cellulose was converted into amidinourea cellulose phosphate.
It was presumed that this property was attributed to the formation of amidinourea by the hydrolysis of dicyandiamide and also to the accelerating effects in the esterification of cellulose by dicyandiamide and the condensed phosphoric acid formed.

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