Phase diagrams of (C₁₂H₂₅)₂N(CF₁₃)₂+Cl- (DDAC), (C₁₄H₂₉)₂N(CHs)₂Cl- (DTAC), and (C₁₈.H₃₇)₂N(CH₃)₂+Cl-(DOAC)-water systems as a function of temperature are presented. It was found that in DOAC-water system, the molecular solution phase, two-phase region of the liquid crystalline and water phases, and the liquid crystalline phase (lamellar structure) exist slightly above the melting point of the hydrated solid surfactant (Krafft point); whereas the region of the micellar solution may present within a very narrow range of concentration between the molecular solution and two-phase region in the cases of DTAC and DDAC-water systems.
Critical concentration to form an aggregate was determined from the surface tension-concentration curve. Two-phase region, composed of dispersed liquid crystal of aqueous solution of DOAC, is optically bluish-white and very stable to phase separation, but splits into, two phases under centrifugation (-19000 g, 1 hr). Various single liquid crystalline phases can be formed through considerably small concentrations, i. e., 18 wt% of DDAC, 3 wt% of DTAC, and 3.7 wt% of DOAC.
The phase diagrams of dialkyldimethylammonium chlorides-water systems resemble those of Aerosol OT and lecithin-water systems. It was considered that each HLB of these surfactants is optimum due to two long-chain alkyl groups.

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The temperature effect of Aerosol OT distribution between water and carbon tetrachloride was investigated and analyzed on the basis of its thermodynamic parameters in both phases in the range of 20-60°C. The standard transfer free energy (from water to carbon tetrachloride) was determined by the direct analyses of solute in equilibrium at dilute concentration. The standard transfer enthalpy was obtained from the enthalpy of solution both into water and carbon tetrachloride. This was compared with the value from the free energy vs. temperature relation. The activity coefficients in both independent phases were obtained from vapor pressure depression data. The standard transfer entropy and heat capacity were obtained from the thermodynamic analyses of the standard transfer free energy and enthalpy. These thermodynamic parameters were discussed on the basis of water structure.

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The electrical conductivity of fine crystals of iron(111) hydroxide oxides (α-Fe.00H, β-FeOOH, and γ-FeOOH) with chemisorbed SO₂ was measured in vacuum under the compression at 400 kg/cm' in the frequency range from dc to 10 MHz and the temperature range from 30 to 120°C. For all samples, the conductivity was considerably decreased by the chemisorption of SO₂ see Fig. The effect of chemisorption of SO₂ was smaller for γ-FeOOH than for α-FeOOH and β-Fe00H. A small change in the activation energy for conduction' was observed after the chemisorption of SO₂. These results were explained by the concept that the excess delectrons are trapped in the vacant chemisorptive levels of SO₂. The sites of chemisorption for SO₂ on the surfaces of FeOOH were estimated by use of the residual electrostatic valence of surface oxygen, which was calculated after the Pauling's theory., An SO₂ molecule appears to be chemisorbed bidentately on two surface oxygen atoms of large residual electrostatic valence in the cases of α-FeOOH and β-FeOOH, and on four surface oxygen atoms of OH for γ-FeOOH.

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Carbonylation of methanol with supported rhodiun metal catalysts was studied under the atmospheric pressure and in the temperature range from 170°C to 250°C. Addition of methyl iodide was necessary for the reaction to take place. Metallic rhodium exhibited a notable activity only when it was supported on active charcoal. Major product was methyl acetate, while minor product being acetic acid. Acetic acid probably forms successively from methyl acetate through its hydrolysis, The selectivity of acetic acid increased with the increase in the reaction temperature. The apparent activation energy of the carbonylation was 8.5 kcal/mol. Reaction orders with respect to the partial pressures of methyl iodide, methanol and carbon monoxide were O.0, 1.0, and O.6, respectively. They differed significantly from the values, 1.0, O.0, and O.0, which were obtained under pressurized condition. The adsorption of carbon monoxide on the catalyst was observed to be weakened by methyl iodide. The reaction path seems to be composed of a sequence of elementary reactions similar to those of liquid phase reaction catalyzed by rhodium complexes. They are the oxidative addition of methyl iodide to rhodium, the insertion of carbon monoxide into the methyl-rhodium bond to form an acyl complex, and the methanolysis of the complex to form methyl acetate and hydrogen iodide. Hydrogen iodide thus formed reacts with methanol very rapidly to form methyl iodide. While the oxidative addition has been pointed out to be the rate determining step in the liquid phase reaction or in the pressurized gas-solid reaction, the methanolysis of the acyl complex is considered to be rate determining under the present reaction conditions.

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NO-CO, NO-H₂, NO-C₃H₆, and NO-NH, reactions have been investigated on a number of transition metal oxide catalysts by pulse reaction technique. The catalysts have been divided into two groups with respect to their behaviors to the above reactions. Namely, Fe₂O₉, Cr₂O₃, CuO, Co₃, NiO, MnO₂, and ZnO catalysts (group A catalysts) are active for all reactions, whereas V20, , MoO₃, WO₃, and SnO₂ catalysts (group B catalysis) are active only for NONH, and NO-C₃H₆ reactions but inactive for NO-CO and NO-H₂ reactions. These results showed that mechanisms of NO-NH, and NO-C, H, reactions may be different from that of NO-H₂ (or NO-CO) reaction. The activity of group A catalysts for NO-NH, reaction is proportional to that for NO-H₂ (or NO-CO) reaction, which suggested that a close relationship between the mechanisms of NO-NH, and NO-H₂ (or NO-CO) reactions may exist on group A catalysts. The selectivity of N₂ in NO-NH, reaction on group A catalyst is lower than that on group B catalysts. The differences in behavior between group A and B catalysts were also found in the kinetics of NO-NH, reaction. Namely, reaction rate of NO-NH, reaction is proportional to on V₂0, catalyst (group B catalyst) and to on Fe₂O₃ catalyst (group A catalyst). It has been inferred that the rate of NO adsorption and the reduction of adsorbed NO by adsorbed hydrogen are slower on V₂0₅ catalyst than on Fe₂O₃ catalyst.

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In order to reveal the features of carbon formation, the decompositisn of butane on supported nickel catalysts was studied, using a pulse technique over the temperature range of 400-500°C. The conversion of butane was proportional to the catalyst weight till the higher, degree of decomposition. This indicates that the conversion is zero order reaction. The anomaly was found in the temperature dependence of reaction rates of some catalysts. In spite of much carbon deposit enough to cover the nickel surface in the catalysts, the degree of decomposition of butane did not decrease at higher temperatures. These characterisics' were not related to the preparation of the catalysts or catalyst supports, but to the crystallinity of nickel. In the case of catalysts with larger size crystalline nickel, there was a flection in the Arrhenius plot, and their catalytic activities were maintained without any decrease at higher temperatures, even though carbon was deposited on them.

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Half-wave potential of Ph²⁺ ion shifts to the negative side with increasing mixing ratio of three kinds of solvents to nitromethane; The above solvents are dimethyl sulfoxide (DMSO), N, N- dimethylformamide (DMF), and propylene carbonate. The solvation numbers of Pb²⁺ ion were determined from the shift of the half-wave potentials due to a change in mixing ratio. These numbers are 5.7, 5.9 and 5.8 for DMSO, DMF and propylene carbonate, respectively, which agreed well with hydration number (5.7). This indicated that Pb²⁺ ion is solvated with six solvent molecules. Logarithms of the formation constants for Pb²⁺ ion solvation are 13.7, 10.2 and 2.5 in DMSO, DMF and propylene carbonate, respectively, indicating that DMSO molecules with high donor number are most strongly solvated to Pb²⁺ ion. Diffusion current (i_d) of Pb²⁺ ion decreases with increasing mixing ratio of the solvents to nitromethane. The decrease in id is proportional to the increase in viscosity (7η) of the mixed solvents. The product of diffusion current and square root of viscosity (i_d, η^1/2) is not constant and decreases with increasing mixing ratio. The proportion of the decrease in 4, 07112 is the largest for propylene carbonate-nitromethane mixture, probably being due to the difference in molecular weight of solvated Pb2+ ion formed by the replacement propylene carbonate with nitromethane molecules.

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By the immersion of flaky natural graphite (20-3/4-50 meshes) into huming nitric acid and subsequent heat-treatment above 100°C, the exfoliated graphite was obtained. It had much bigger specific area (Table 1) and larger lattice strain (Table 2) than the original graphite. On the exfoliated graphite, much faster fluorination was achieved (Fig.1 and Fig.2). The dissociation of fluorine molecules to atoms was found to be a rate-determining step in the formation of graphite fluoride from the exfoliated graphite, whereas the process of diffusion of fluorine molecules was the rate-determining step on the original flaky graphite. The graphite fluoride obtained from the exfoliated graphite had larger interlayer spacing, better crystallinity and larger fluorine content than that from the original graphite (Table 3).

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This paper describes the appearance and disappearance of during the growth of emerald single crystal prepared by V₂O₅ flux method. Both spherical seeds of 5 and 10 mm in diameters, and thick platy seeds cut parallel to crystallographic orientations and noncrystallographic orientations of 5 and 10 mm in length were prepared from natural beryl. Their surfaces were polished and made smooth. All experiment were runs at 1050°C and zit was made 10°C. When spherical 10 mm seed was used, m (1010) and c (0001) appear at the earliest stage, (before 5 hrs) followed by the appearance of a (1120), p(1011), o (1122), s (1121), u (2021), v (2131) and n(3141) after 8 hrs. After 10 hrs, u-, v- and n-faces disappeared. A small prism face (3140) was observed between m- and a-faces, and soon disappeared as growth proceeded. o-, s- and p-faces disappeared after 200, 250 and 275 hrs, respectively. The final morphology after 275 hrs was hexagonal prism consisting of only c (0001) and m (1010). In the case of thick platy 10 mm seed cut parallel to non-crystallographic directions, c (0001) m (1010) and a (1120) faces appeared at first (after 5 hrs), followed by the appearance of p-, sand o-faces after 24 hrs. The latter two faces disappeared after 165 hrs and the former face after 270 hrs. The final form was again hexagonal prism consisting of c(0001) and m(1010) only. In the case of thick seed of the same size cut parallel to crystallographic directions, the faces parallel to the cut plane appeared and developed well at first, but u-, v- and n-faces, which all inclined at higher angle to the c-face, disappeared after 100 hrs. o- and s-faces remained after 300 hrs and p-face after 500 hrs. In any case, the final forms were similarly hexagonal prismatic form consisting of c(0001) and m(1010) faces.

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An attempt to grow crystals of LiGaO₂ and LiGa₅O₈ was made by slow cooling of Pb0- 1320. flux with varying Pb0/13208, in which LiGaO₂ was dissolved as a solute.
About 43 g of LiGaO₂ was dissolved in 100 g of Pb0(80 mol %)-13203(20 mol %) flux at 1300°C.
The growing of crystals was conducted by heating mixtures at the highest temperature of 1300°C for 5 hours followed by cooling to 500°C with a rate of 5°C/hr.
LiGaO₂ or LiGa₅O₈ crystal grew from the flux of PbO(100-60 mol%)-B₂O₃(0-40 mol %) or Pb0 (55-15 mol%)-13208(45-85 mol%), respectively. It seemed that the growth of two kinds of lithium gallium oxide crystals mainly results from the difference in the amount of chemical reaction between B₂O₃ (an acidic oxide) in the flux and a part of Li20 (a basic oxide) in the solute.
Densities of LiGaO₂ and LiGa₅O₈ crystals, picnometrically determined, are 4.24 and 5.81 g/ cm', respectively. They were in good agreement with the calculated values.

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Pyrolyses of the mixtures of (NH₂)₂C0 and KH2PO₄ were carried out and the properties of the products were studied to explore the possibility of introduction of P-N bonds into the condensed phosphates. The mixtures in various molar ratios of (NH₂)₂C0/KH₂PO₄(=U/P) were heated at 850°C for 1 hr and quenched. Nitrogen content in the products increased with the increase of the amount of urea until the U/P reached 5, above which nitrogen content was almost uninfluenced by the change of U/P. The amount of nitrogen in the form of ammonium ion was very little. The average chain length of the resultant phosphate, ft, was markedly reduced by the inclusion of nitrogen. DTA curves of mixtures showed exothermic peaks near 300°C, whereas DTA of individual (NH₂)₂C0 and KH₂PO₄ did not show any exothermic peak. The absorption bands, which might be associated with P-N bond, were found in the IR spectra of the products obtained by heating the mixture at 300°C for 1 hr. The mixture of high U/P gave a colored amorphous substance. When it was reheated at 300°C for several hours, the color faded and ftincreased by a factor of about three, accompanied with deammoniation. Above results suggested that the condensed phosphates with terminal groups of -NH, were formed in the present process. During the pyrolysis of the mixture of high U/P, the groups of P-0 and P-O-P were reduced to give the lower oxophosphates and the homologues of phosphorus-hydrogen compounds containing phosphine.

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The influence of sodium aromatic sulfonates including two series of anionic surfactants, on the hydration of alite (3 CaO, SiO₂ solid solution) and portland cement was studied by means of conduction calorimeter (see Fig.2). And dispersion of cement with anionic surfactants was discussed by means of sedimentation velocity. Amount adsorbed on cement was determined by UV method.
Compounds consisting of short hydrophobic chains scarcely affected the hydration of cement (see Table 2). Anionic surfactants retarded remarkably the hydration, and the retarding mechanisms were dependent on the structure of anionic surfactants. Type I anionic surfactants have a hydrophilic group (-SO₃Na) at the end of the molecule. Type ii anionic surfactants have hydrophilic groups in the molecule.
Surfactants of type I showed the critical amount of addition. The hydration of cement was not retarded when less surfactants were added than the critical amount, but it was strongly retarded when more surfactants were added than the critical amount. On the other hand, in the case of type II, retarding effect became gradually larger with increasing amount of surfactants (see Table 2, Fig.8).
It was suggested that surfactants type I, when present more than the critical amount (see Fig.14-(a)), were closely adsorbed on cement particles. And the hydration of cement was inhibited by the close adsorption of type I anionic surfactants. But in the case of type If anionic surfactants, instead of close adsorption, flat adsorption occurred (see Fig.14-(b)).
These results were consistent with the results of sedimentation velocity and amount adsorbed (see Fig.10, 12).

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Isotope dilution mass spectrometry was applied to the determination of a minute amount of copper in the Watarase river water, inter-laboratory cross check sample in Japan. Sample size required was smaller than 1g. The sample was taken into a 50 ml teflon beaker and 0.5μg of ⁶⁵Cu spike in O.4 g of O.1 N nitric acid was added. The spiked sample was treated with each 50 μl of nitric acid and perchloric acid and was evaporated to dryness in a heated pyrex glass oven being supplied with the high purity nitrogen gas. The residue was dissolved in a mixed solution of 15μ of 0.9 % phosphoric acid and 30 μl of O.06% silica gel suspension solution. Through a micro-pipette tipped with polyethylene capillary, an aliquot of this concentrated solution was loaded onto the center of a single rhenium filament, ion source unit of a Hitachi RMU-6 Type mass spectrometer. The isotope ratio of the spiked sample, ⁶³Cu/⁶⁵Cu, could be recorded with the coefficient of variation from O.3 to 2.2%, the detection limit being O.08 ng. The copper concentration in the Watarase river water was found te be 58.6± 0.5 ppb and accorded with those by other methods such as atomic absorption spectrophotometry and neutron activation method.

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In the flame emission spectrophotometry of europium, 0.5 molt/ ammonium perchlorate increased the emission intensity of europium by about 2.4 times for air-hydrogen flame and by about 2.2 times for air-acetylene flame, respectively. These enhancing effects were applied to the elimination of the interferences of various coexisting elements and aids on the determination of europium.
The interference of aluminium was not eliminated, but those, of other elements including rare earth elements were completely eliminated by the addition of 0.5 mol/l ammonium perchlorate. The interferences of hydrochloric, nitric and perchloric acid in the concentrations below 0.5 moll/ were eliminated by the same method.
Europium oxide added to calcium oxide was determined without matrix interference in the presence of O.5 mol/l ammonium perchlorate.
The results obtained by using both flames agreed with each other.
The coefficients of variation of the present method were 1.1 % for air-hydrogen flame and 2.5% for air-acetylene flame, respectively.

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In the flame emission spectrophotometry of ytterbium by using air-hydrogen and air-acetylene flame, the emission intensity of ytterbium remarkably increased in the presence of ammonium perchlorate. In the case of 0.5 molfi ammonium perchlorate, the increases were by about 4.5 times for air-hydrogen flame and about 19 times for air-acetylene flame, respectively. These enhancing effects were applied to the elimination of the interferences of various coexisting elements and lithium. tetraborate on the determination of ytterbilm. The interference of aluminium was not eliminated, but those of other elements including rare earth elements were completely eliminated by the addition of 0.5 moll/ ammonium perchlorate. Though the lithium tetraborate remarkably supressed the emission intensity of ytterbium, ytterbium oxide added to lithium tetraborate was determined without matrix interference in the presence of 0.5 mol/l ammonium perchlorate in, the both flames. The results obtained by using both flames agreed with each other. The coefficients of variation of the present method were 1.4% for airhydrogen flame and 2.3% for air-acetylene flame, respectively.

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The adaptability of KAP, RAP, and TAP analyzing crystals for the fluorescent X-rays of the ultra-light elements such as F and Na was compared. The intensity of reflected fluorescent X-rays, the peak to background ratio of the fluorescent X-rays, the wave distribution of incident X-rays, the fluorescent X-rays of crystal surface, and the stability of crystals were evaluated as the factors to select the analyzing crystal.
The disperse ability of three crystals was the same extent, because these surface spacings were almost identical. The intensities of reflected fluorescent X-rays for the experimental relative ratios were TAP: RAP: KAP= 100: 59: 33 on Na-K_a, line and 100: 63: 31 on F-K_a line. The intercept of the intensity to the curve by KAP gave the value of about twice as much as that TAP on the calibration curves of fluorine. In addition, the angle of the tangent to the curve by ATP was larger by a factor of 4 than that by KAP. Therefore, the values obtained by using TAP showed greater precision than that obtained by using KAP. This fact was also proved from the standard deviation of fluorine in the cement samples. The detection limits for the cement sample were 0.028 % for TAP, O.052 % for RAP, and O.142 % for KAP on fluorine, and 0.004 % for TAP and O.009 % for RAP on sodium.
On the other hand, the precision and the sensitivity were improved by using the detector equipped with the gas-density stabilizer and center-wire cleaner and consequently the variation of X-ray intensity and the lowering of disperse ability were suppressed by the above method.

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A system has been developed in which kinetic phenomena are followed by rapid transfer of successive free induction decay signals (FID) to floppy disk on line with FT-NMR. Carbon-13 chemically induced dynamic nuclear polarsation (CIDNP) from thermal decomposition of benzoyl peroxide in tetrachloroethylene was observed by 39 parallel accumulation without sequential time averaging.
Thus we found polarized peaks which weakly appeared temporarily during the course of the reaction and the polarized peak due to tetrachloroethylene.
Pentachloroethane appears to be formed from multiple reaction paths and tetrachloroethylene is reproduced by free radical reaction. A possible formation of C₆H₅CO-0-Cl is suggested from CIDNP spectra and mass spectroscopy. Intermediate formation of CCl₂=CCl. is also estimated from mass spectroscopy.

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The oligomerization of furan catalyzed by hydrochloric acid gave two major products, 4, 7-di(2-furyl)-4, 5, 6, 7-tetrahydrobenzo[b]furan [1] and 2, 4, 4-tri (2-fury1)-1-butanol [2]. The former was dehydrogenated to afford 4, 7-di (2-furyl)benzo[b]furan [3] by treatment with tetrachloro-p-benzoquinone and the latter was converted to its acetate [4] by acetic anhydride.
The formation of the tetramers and 2 is considered to proceed via the trimers, 2, 5- di (2-furyl) tetrahydrofuran [5] and 2, 4-di (2-furyl) tetrahydrofuran [6], respectively. The tetrahydrofuran ring of the latters was immediately cleaved by acid to give the corresponding hydroxy derivatives, 1, 4, 4-tri(2-fury1)-1-butanol [8] and [2]. The butanol [8] was converted to [1] by the intramolecular ring closure via the stable carbonium ion [9], but the similar reaction of [2] did not occur. The mechanism appears to be reasonable on the basis of the fact that the 1-phenyl-1, 2, 3, 4-tetrahydronaphthalene was formed by the reaction of 1, 4- dipheny1-1-butanol and hydrochloric acid.

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The oxidation of 1, 2, 4, 5-tetramethylbenzene (TMB) was investigated under the pressure of oxygen using two or three transition metal salts and bromide as catalysts in acetic acid. Activities of the catalysts, composed two transition metal salts and bromide, are in the following order, Co-Mn-Br > Co-Ce-Br> Co-Br >Co-Cr-Br=Co-Ni-Br > Mn-Ce-Br > Ce-Cr-Br. The multiple effect of Co-Mn and Co-Ce in the presence of bromide was observed at various atomic ratios, even hundredth of Mn or Ce to Co, and Co to Mn. The activity of Co-Mn-Br is affected by the addition of other metal salts. The effect of these metal salts on the oxidation of TMB is in the following order, Ce> none addition> Hg= Cr=Ni> Sn>>Zr>>Cu. Thus, Co-Mn-Ce-Br was found to be more active catalyst than Co- Mn-Br.
The initial rate of oxidation catalyzed by Co-Mn-Br or Co-Mn-Ce-Br under 20 kg/cm² of oxygen pressure is independent of the concentration of TMB. However, the yield of pyromellitic acid and the extent of oxidation increase with decreasing concentration of TMB.
The distribution of the products was also studied as a function of an extent of oxidation. The couse of reaction from TMB to pyromellitic acid and the high selectivity of the latter were elucidated.

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To study the photofading reaction of azo dye, the photofading of 1-arylazo-2-naphthols [1] in certain solvents has been examined.
Upon photofading of 1-p-tolylazo-2-naphthol in methanol under oxygen atmosphere, pmethylanisole, p-anisic acid, and methyl p-anisate were obtained as main products. The rate of photofading of [1] was accelerated in the presence of Methylene Blue, a singlet oxygen photosensitizer. While, this reaction was inhibited by the addition of 1, 4-diazabicyclo[2.2.2] octane, a singlet oxygen quencher, and more than 90% of unchanged starting material remained. The rate of photofading of [1] was studied with regard to the solvent effect on a singlet oxygen production as well as its destruction. From these results, it was suggested that the photofading of [1] in solution may be dependent on a self-sensitized photooxidation by a singlet oxygen. Attack of a singlet oxygen to hydrazone, tautomeric form of [1], gave unstable peroxide [13] type intermediate, which decomposed to give 1, 2-naphthoquinone and p-substi- tuted benzenediazonium ion. The latter species reacted with methanol to form methoxybenzene derivatives.

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The basicities of azo and anthraquinone disperse dyes in an aqueous solution were determined spectrophotometrically by means of Eq. (7) and the relations between the basicity and the chemical structure of the dyes were discussed.
Where εd and edi, are molar absorptivities of the neutral and the ionized dye respectively; ea, is apparent molar absorptivity of the dye solution at varied pH. The plots of e. (ε_spp-εd)10^PH gave a straight line and the value of the pKa was obtained from the slope of the regression line. The pK_a of one of the amino nitrogen in an anthraquinone dye (1) depended on the pKa of the aromatic amine adjacent to the quinone nucleus of the dye(Table 5, 6, Fig.11).
The protonation to an azo dye C 8 took place on the 8-azo nitrogene and its basicity was determined in terms of linear plots of Eq. (7) by employing the longer wavelength than 500 nm.
The introduction of substituents at X, Y-positions varied definitely the pKa of 8-azo nitrogen (Table 1, 2). The basicity of 8-azo nitrogen depended rather on the pKa of the anilines, which used as a coupling component of the dye, than on the Hammett's 0. value of the substituent Z at p-position (Fig.9, 10).

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Wetting energies at Vinylon/water interface increased with increasing concentration of poly (ethylene oxide) (PEO) up to a certain concentration, being tentatively termed critical adsorp- tion concentration (CAC), beyond which the wetting energy approached a limiting value. The values of the CAC of PEO with molecular weight of 0.5×10⁶(PEO-3 N), 1.7 × 106(PEO-10N) and 3.5 × 10⁶ (PEO-18 N) were 0.05, 0.01, and 0.008 g/100 ml, respectively. The adsorbed amounts of PEO-10 N and PEO-18 N on Vinylon/water interface from solution, whose concentrations being higher than CAC, were found to be two-three times greater than those calculated by assuming a monomolecular adsorption layer consisting of closely packed randorp-coiled PEO molecules. C-Potentials of Vinylon fibers in PEO solution decreased with increasing concentration of PEO. The C-potential of Vinylon fibers at CAC has coincided with the calculated value of C-potential obtained by assuming a shear plane to be located within the monomolecular layer thickness in diffused double layer at the interface. The (mean) surface coating rate of Vinylon surface by PEO, whose concentration being lower than CAC, was estimated from ζ-potential vs. concentration curves and the result has been discussed in terms of Frumkin isotherm. The ζ-potentials at higher concentration than CAC decreased with increasing thickness of adsorbed layer which was estimated by the adsorbed amounts and the volume per molecule of closely packed random-coiled PEO. These results suggested that PEO molecules are adsorbed on Vinylon surface in a random-coiled form of the nearly same configuration as in solution, whose concentration being lower than CAC, and in a deformed random-coil or so-called looped form extended toward the solution, whose concentration being higher than CAC.
Permeation properties of PEO solution toward the fiber bed have been discussed in view of the present experimental results.

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The polymerization of isoprene catalyzed by TiCl₄-Al(i-Bu)₃ in benzene was investigated to see a drop in polymerization: It was found that a commercial cis-1, 4 polyisoprene, when contacts with catalyst, degrades the catalytic activity and that [η] of the obtained polymer decreases with progressing polymerization. On the basis of these facts, it was considered that a drop in polymerization was due to the scission of chain of the polymer. In order to retard this scission, the polymerization of isoprene was studied in the presence of several amines. Upon addition of certain secondary amines to isoprene, the polymer with [η]=4 was easily obtained.
The equilibrium constants (K'_N) of the adsorption, in the presence of certain secondary amines, were calculated and compared them with [η] of the obtained polymer. A good cor- relation between K'_N and was found. It was concluded that certain secondary amines, producing large.1 value, are preferable to retard the scission of chain of the polymer, produced by the addition of TiCl₄-Al(i-Bu)₃ catalyst.

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The effects of cobalt on Mo03-Co0/Al₂O₃ catalysts have been investigated in relation to the behavior of adsorbed oxygen by means of ESR and X-ray diffraction methods.
The addition of cobalt to MoO₃/Al₂O₃ catalyst causes the stabilization of 0, - ads-orbed on the catalyst and inhibits the formation of MoO₃ crystallite. The O₃- adsorbed on heptavalent molibdenum of MoO₃-CoO/Al₂O₃ catalysts is remarkably reactive for propylene.

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Linear equations, taking into account the presence of certain strong acid or base, were proposed in order to determine simultaneously the concentration and dissociation constant of monobasic weak acids by using the results obtained by a potentiometric titration.
The volume of titrant (Δv) equivalent to the weak acid, the volume of titrant (v₆) equivalent to the strong acid, and the dissociation constant of the weak acid (K) can be determined by applying the titration data to the following equation and solving the resulted equations simultaneously:
where z is a function of both the volume of titrant and the pH value, and a_H is the activity of hydrogen ion.

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gem-Dichlorocyclopropanes were reduced easily by lithium aluminium hydride in boiling tetrahydrofuran to afford cis-trans mixtures of the corresponding monochlorocyclopropanes. The cistrans ratios were determined by GLC. The relatively high isomer ratios were obtained for the reduction of (2, 2-dichloro-cyclopropyl)benzene and 7, 7-dichloronorcarane in both of which a hydrogen atom in the substituent is close to the cis-chlorine atom. The reduction proceeds presumably via a synfacial mechanism in which the attacking hydride and the chlorine atom attacked are on the same side of the cyclopropane plane.

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The SO₂ adsorption isotherms of the precipitates obtained by culturing Thiobacillus Ferrooxidaris in iron (II) sulfate solution were determined by a gravimetric method. Although X-ray diffraction diagrams of dry precipitates were identical to those of jarosite (KFe₃(SO₄)₂(OH)₆), it was observed that the structure became amorphous by washing with distilled, water and the surface area increased accordingly. Only the crystalline products showed remarkably high adsorption for SO₂ (1.32-1.51 mg/m²). A possible correlation between high SO₂ adsorption capacity of the bacterial oxidation products and the layer structure of jarosite was inferred.

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