The phase transition point of I(Cl-13), C-C(CF-13)3 was found in terms of differential thermal analysis to be about 5°C. An X-ray study of the powdered sample showed that the crystal belonging to the high-temperature solid phase consists of body-centered cubic lattice with a=7.84A and Z=2 at 15°C. A comparison between symmetry of the molecule and that of the crystal led to the conclusion that in the high temperature solid phase the constituent molecule has the freedom of both orientational and rotational motions.

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The adsorption isotherms of fatty acids (sodium salts) with various carbon numbers (N) on activated carbons with different pore size distributions were measured in aqueous solutions. The observed isotherms were well fitted by the following equation:
CC x=7, (ex, a: constant)
where a expresses the adsorbability at infinite dilution. The a was found to be related to the carbon number N of the solute by the following:
log a. PT-Fr (r: constant)
where 8 is positive. For the solute with same N, a increased with decreasing mean pore radius of activated carbon. increased with decreasing pore size.
These results were discussed in terms of adsorption thermodynamics.

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In the presence of poly (vinylpyrrolidone) (PVP), the amount of sodium dodecyl sulfate (SDS) adsorbed on kaolinite was smaller in the low concentration of SDS than that for the case of no PVP added, while the amount was larger in the high concentration of SDS than that for no PVP. The amount of SDS adsorbed on kaolinite for no PVP added followed the Langmuir type isotherm. The PVP adsorption showed that the adsorption increased or decreased with the increase of SDS, depending on the affinity of adsorbed PVP (or PVPSDS complex) to water and the conformation of the PVP or the complex. These phenomena were explained by the competitive or cooperative adsorption of PVP and SDS.
The SDS adsorbed on kaolinite was divided into two groups; SDS directly adsorbed on kaolinite and SDS forming the complex with PVP on kaolinite. It was suggested that the binding ratio of SDS to PVP in the complex on kaolinite was larger than that in the bulk solution.
Comparison of the adsorbability of kaolinite with its dispersibility showed that the amount of adsorbed PVP required for the sufficient disperse of kaolinite was much less than the maximum amount of PVP adsorbed on kaolinite. The mean diameter of kaolinite particles in the suspension became smaller by the addition of PVP to SDS than that for no SDS, and the addition of SDS before PVP was more effective than the addition of PVP before SDS.

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A copper-evaporated organic film, consisting of a poly (vinylchloride) -type matrix and a photochromic benzospiran derivative, was tinged with magenta (Amax = 520 nm) and copper was removed from the surface under successive treatments of electron bombardment (12 kV-7 x 10-7 coulomb/cm²) and heating (about 150°C). The coloration was due to the formation of a colored chelate (metallochrome) and closely related to a change in chemical properties of the surface copper. In the bombarded part, an open-ring species of benzospiran derivative (1', 3', 3'-trimethy1-8-methoxy-6-nitrospiro[2 H-1-benzophyran-2, 2'-indoline]: SP), showing a chelating function, and hydrogen chloride, liberated from the matrix, appeared. By post-heating, a magenta copper (II) chelate was formed between an open-ring species of SP and copper (II) chloride, prepared by the liberated hydrogen chloride, at the boundary of two layers. The thermal change in the surface copper was influenced by heating conditions. The chlorination of copper was active in air to accelerate the chelation. As a result, the surface copper layer of thickness 20A apparently diffused into the organic layer by the chelation.
This phenomenon (metallochromic doping) is expected to be useful for electron lithography to form a metallic hard mask for producing integrated circuits and to apply to a digital micro-recording medium. A positive-type metallic pattern, consisting of an additional deposited metal, was formed on residual copper in the nonbombarded surface.

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The high dielectric constant films of 40 to 106 were obtained by dispersing 4 to 8 weight percent of N-methylacridinium- (7, 7, 8, 8-tetracyanoquinodimethane) complex salts (MA CO₂') in butyral resin modified with epoxy polymer. The dissipation factors of the films were in the range of one to two percent, but the electrical properties of the film varied depending on the polymers used and the manufacturing conditions of the composite films, although the concentration of the charge transfer complex in polymer was fixed. Electrical, chemical and optical analyses of the film have revealed that the mechanism of the observed high dielectric constant was due to the precipitation of many fine charge-transfer crystals separated from each other with extremely thin polymer layers. In conclusion, the evidence presented in this study indicates that the composite film is considered as a kind of barrier-layer dielectrics, that is, extraordinary thin layers of the polymer, which exist among charge-transfer complex crystals, work as dielectrics.

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Cerium silicon triphosphide (P-type), CeSiP3, is orthorhombic with a = 5.861 ( 1 ), b= 5.712 ( 1 ), c= 25.295 ( 3 ) A, V=846.7 A3, space group Pn21a and Z=8. The crystal structure has been determined by the Patterson method from the X-ray intensities of 1372 independent reflexions measured on a four-circle automatic single-crystal diffractometer, and refined to R = 0.048.
This structure is probably characterized by the following layer arrangement along the cxis,
[P] [Ce] [SiP2] [Ce] P [Ce] [SiP2] [Ce]
Ce atoms have an approximately square-planar coordination in the [Ce] layer. In the p layer, two-linked P atoms form one-dimensional zigzag chains along the b-axis, P-P distances being 2.25 and 2.35A. In the [SiP2] layer, six-membered rings with boat conformation form two-dimensional infinite network perpendicular to the c-axis. Each Si atom is linked with deformed tetrahedron of P atoms, and then half of P atoms are linked with three Si-atoms, while the rest are linked with one Si atom. The one-linked P atoms are at the position of the bridging atoms to the [Ce] layer. Each Ce atom is surrounded by nine P-atoms in this structure. The average Ce-P distance is 3.08A.
Lattice constants for LnSiPs (Ln =Ce-Sm) shows lanthanoid contraction, the extent being especially large along the a-axis.

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The rates of hydrolysis of sodium dithionate in a phosphate buffer solution (0.2 mol//), sodium hydroxide solutions (0 to 1.02 mol/l) and sulfuric acid solutions (0 to 0.780 mol//) were investigated in the temperature ranges 140 to 180, 120 to 150, and 80 to 130°C, respectively. It was found that the hydrolysis of sodium dithionate was an acid-base catalytic reaction, and that the overall reaction rate was expressed as follows:
[S₂062-]/d t=(katf1+1+kaq kb[011-1ENa+]) [S₂062-] log ka=17.735-28.1 x 103/4.58 T-4 SVI-/(1+ I) (m^-1r-') log kaq=13.607-32.5 x103/4.58 T (hr-') log kb=12.093-26.6 x 103/4.58 T-I-2 SV I 1(1+ AST-) (m^-2. hr-')
where S is the Debye-Hiickel limiting slope, and AK is the only adjustable parameter at each temperature. The rate-determing steps in the alkaline and acid hydrolysis are probably the reaction between NaS₂06+ and 0H⁺, and S₂06' and H⁺, respectively.

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Needle crystals of BaW04 were prepared by slow cooling of the high-temperature solution consisting of binary mixture of BaWO₄ and KCl. A mixture of BaWO₄ and KCI was kept at 900 or 1000°C for 5 hr and gradually cooled to about 500°C at a rate of 5°C/hr. Results obtained are summarized below:
(1) Needle crystals of BaW04 were obtained from the fluxed melt whose solute content being 1-35 mol% (soaking temperature was 900°C) or being 1-15 mol% (soaking temperature was 1000°C)
(2) The needle crystal, whose maximum length being 3.4 mm and whose diameter being 25, a, was obtained. The needle crystal thus obtained was tetragonal prism and had silky luster and smooth surface.
(3) The growth direction of needle crystal was <001>.

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Fibrous vanadate crystals of the system V205-H₂0 were synthesized hydrothermally at temperature ranging from 200 to 600°C under water vapor pressures of 50 to 400 atm for a duration within one month. A reagent grade V20, and its crystalline mass obtained by cooling after melting at 800°C for five hours were used as the starting materials. The products were examined by X-ray diffractometry, microscopic observation, infrared spectrometry, differential thermal analysis etc.
A solubility curve of V205 in water at a constant pressure of 200 atm for two days showed that about 1.9g of V205 dissolved in water at 320°C and above 400°C its solubility decreased with increasing temperature. The length of the fibrous vanadate crystals increased with the treatment time below 320°C, but decreased above 400°C, at a constant pressure of 200 atm. Vanadate fiber length had a tendency to increase with the increase of temperatures and pressures in synthesis. The optimum conditions were found to be near 500°C and 200 atm for one hour treatment. The pH of the solutions in the reaction at 400°C and 200 atm for two days, affected the length of fiber. Long fibers were synthesized at the pH of 2.8, 4.2 and 6.0 after the reaction. X-ray powder diffraction patterns showed that V205 H₂O (navajoite) was stable under present experimental conditions and that above about 500°C V20520 and an unknown phase with platy crystal habit were produced with navajoite. DTA curves showed that a large peak for the endothermic reaction near 610°C was attributed to the evaporation of bond water. An absorption band near 3500 cm-' on IR spectrum was assigned to the vo. or vH₂0 stretching vibrations and a band near 1000 cm-' to the vv =0 stretching vibration. A silky fiber (navajoite) having a maximum length of 3.6 mm and 1 pm in diameter was synthesized. The fiber was elongated along [010], and found to have a light brown color and flexibility.

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8-Quinolinol and its derivatives (5-sulfo-, 2-methyl- and 5, 7-dihalo-8-quinolinol) exhibit intense fluorescence in concentrated acids at an ordinary temperature, but water quenches this fluorescence. Excited singlet state properties of these compounds in concentrated sulfuric or perchloric acid have been studied. Absorption and fluorescence spectra, prototropic equilibrium constants between cations and zwitter ions, fluorescence quantum yields, fluorescence lifetimes, and fluorescence polarization spectra were investigated.
The maxima in absorption and fluorescence spectra of 8-quinolinols shifted to longer wavelengths; the quantum yield and the lifetime of the fluorescence diminished with decreasing concentration of acids. From the results, the fluorescence of 8-quinolinols in concentrated acid has been attributed to an inhibition of n-ir transition due to protonation of quinoline nitrogen. The same was true for the fluorescence of metal 8-quinolinolates; i. e., an inhibition of n-ir transition in 8-quinolinols due to protonation or chelation brought about fluorescence, and the fluorescence sensitivity indexes of these compunds decreased with decreasing atomic number of the central atom: H+A13+Ga3+In3+ for 8-quinolinolate, H+Mg2+ Zn2+Cd2+ (tetrahedral) Als+Gas+In3+ (octahedral) for 5-sulfo-8-quinolinolate.

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AB206 Type oxides, where A=Mg, Ni, Cu, Co, Zn, Mn, and Ca; B-=Nb or Ta, were grown from a Na₂13407+B203 flux below 1300°C. All of the ANb2O6 crystals have the orthorhombic columbite structure. ATa206 crystals of A=Mg, Ni, and Co have the tetragonal tapiolite structure, and those of A=Cu and Mn have the columbite structure. For ZnTa2O6 obtained, tetragonal and tapiolite type phases coexisted. The solid-solution of ANb2O6-ATa2O6 system with A=Mg, Co, and Zn has been found as partially soluble.

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1-, 2-, 3-, and 4-Hydroxyquinolizinium bromides were synthesized from the corresponding derivatives of pyridine, and their plc values were spectrophotometrically determined in aqueous solution.
2- and 4-Hydroxyquinolizinium bromides are strong acids, as is to be expected from the conjugation between hydroxyl group and azonia nitrogen. But the pKa values of 1- and 3- hydroxyquinolizinium bromides were also considerably smaller than 1- and 2-naphthols, isoconjugative to them, respectively (Table 4). The pKvalues can be linearly plotted to the effective 7r-electron density defined as -4= go/ (1+ anro, o) on the basis of the Hiickel MO omegatechnique (Fig.2).
The linear plots of the plc, values against the effective 7r-electron density can be classified into three groups of A, B, and C A-group includes the hydrocarbon 7r-electron system, B-group the 7r-electron system having a dipole moment, and C-group the system possessing a cation. The differencies among them are reasonably ascribed to the electrostatic interactions between the proton and the dipole moment or the cation. The calculations of the electrostatic interactions by using the equation proposed by Kirkwood and Westheimer are found to be rather in good agreement with the observations (Table 7), in spite of some simplifying assumptions. The solvent effect on the plc, value was also discussed from the above mentioned viewpoint (Tables 9 and 10).

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The PMR solvent shifts (Peel, - vc6D6) of the methyl (or methylene) groups attached to the nitrogen atoms in 2, 4-dimethyl (or diethyl) -3, 5-bis (arylimino) -1, 2, 4-thiadiazolidines, 2-aryl3-arylimino-4-methyl (or ethyl) -5-methyl (or ethyl) -imino-1, 2, 4-thiadiazolidines, 2-methyl (or ethyl) -3-arylimino-4-aryl-5-methyl (or ethyl) imino-1, 2, 4-thiadiazolidines, and 2, 4-dimethy1-3, 5-bis (arylimino) -1, 2, 4-thiadiazolidine 1-oxides have been measured and related to the Hammett a constants or the Taft a constants (Table 1, Figs.1-7). From these experimental results, it was found that there was a reasonably good correlation between the solvent shifts (vcci, c6D6) for the methyl (or methylene) groups attached to the sp2-hybridized nitrogen atoms and the corresponding Hammett a constants (Table 2, Figs.1-7). On the other hand, the solvent shifts for the methyl (or methylene) groups attached to the spa-hybridized nitrogen atoms have been shown to be correlated with the corresponding Taft a constants (Table 2, Figs.1, 3, 4 and 6).
The results can best be explained in terms of the concept of the conjugated system between the nitrogen atoms and the benzene rings in the 1, 2, 4-thiadiazolidine derivatives. t Studies on 1, 2, 4-Thiadiazolidine Derivatives.

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Catalytic activity of molybdenum metal powder (ref eyed to as Mo-p) on the epoxidation of various olefins with t-butyl hydroperoxide(t-BuO0H), and the effect of solvents on this reaction have been investigated. The catalytic reaction was found to be highly selective for the epoxide formation with high conversion of the hydroperoxide. The reactivity of 1-hexene, 1-octene and cyclohexene correlates well with the ionization potential of the olefins. This correlation suggests that the reaction proceeds through the electrophilic attack of the hydroperoxide on the olefins. The rate of epoxidation of cyclohexene was found to be first order with respect both to cyclohexene and t-BuOOH. The activation energy was estimated as 24 kcal/mol, which was very close to that of the epoxidation catalyzed by MoOs (25 kcal/mol). These kinetic behavior shows that the present catalytic reactions are similar to those catalyzed by other molybdenum compounds reported in the literature. The heterogeneous epoxidation with Mo-p seems to proceed along the same scheme as that of the epoxidation in the homogeneous system.
The solvent such as an alcohol, ether or ketone reduced the reactivities. The inhibiting order was as follows: 2-propanol-BuOHt-BuOHCl, 4-dioxaneyclohexanoneanisole. Due to the interaction between Mo-p and the electronegative oxygen atom, the reaction of Mo-p with t-BuOOH was considered to be inhibited. The solvents carrying no oxygen atom in the molecule did not hinder the intermediate formation of Mo-p with t-BuOOH.

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The predominant tautomeric structures of reaction products [3] of acyclic 8- (monosubstituted amino) a, 0-unsaturated ketones or ethyl 8-(monosubstituted amino)crotonates (substituent: Ph, Me, H) with benzenediazonium salt were elucidated. From the IR and NMR spectral data, it was shown that [3 a--' j] existed entirely in the intramolecular NH... N hydrogen bonded form. In nonpolar solvents at room temperature, the methylimino derivatives [3 b, e, h] were concluded to exist as a tautomeric equilibrium mixture of imino hydrazo form ( B ) and enamino azo form (C ), while in polar solvents the ( C ) form predominated. The phenylimino derivatives [3 c, f, j] were inferred to exist predominantly as the (B) form both in nonpolar and polar solvents at room temperature.

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Kinetic studies on the reaction of terephthalic acid with ethylene oxide to form bis[2- (2- hydroxyethoxy) ethyl] terephthalate (BEET) were made in the presence of quaternary ammonium terephthalate (HOOC-C6H₄-000eN0 (C₂H₅) 3C₂H₄0H) in nitrobenzene. When an excess of ethylene oxide was allowed to react with terephthalic acid, esterification of terephthalic acid proceeded in the initial stage, then hydroxyl groups, generated in the initial stage, reacted with ethylene oxide to give BEET.
Such an etherification already proceeded in the initial stage as a side reaction and yielded small amounts of BEET. It was concluded that this reaction proceeded in terms of two different mechanisms depending upon the presence or absence of terephthalic acid in the presence of terephthalic acid free hydroxyl groups reacted directly with ethylene oxide, forming hydrogen bonding with acid or alcohol, to form ether linkage while in the absence of terephthalic acid occurring after its consumption, quaternary ammonium alkoxide (HOC₂H₄0OC-C6H₄-COOC₂H₄09N(C₂1-15) 3C, H₂OH) reacted with activated ethylene oxide.

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The Michael reactions of 2-pyridone, 3-nitro-2-pyridone or 4-pyridone with substituted ethylenes gave 1-substituted pyridones. The orientational selectivity of electrophilic ethylenes in those addition reactions was opposite to that of nucleophilic ethylenes, For example, the reaction of 2-pyridone with methyl acrylate gave methyl 3-(2-oxo-1, 2-dihydro-1-pyridyl) propionate and with ethyl vinyl ether gave 1- (1-ethoxyethyl)-2-pyridone.
When poly or symmetrically substituted ethylenes were used, Michael reactions did not take place.
The rection mechanism of pyridones with ethylenes were discussed.

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The formation of resin containing phosphorus by the reaction of diphenyl phosphonate (DPP) with aldehydes has been investigated. In particular, formaldehyde reacted vigorously with DPP to produce novolak type resin containing phosphorus. Thermal properties, solubility, and curing of this resin were examined in comparison with those of phenol resin (Novolak).
The yield was 91.0%, and the amount of phosphorus contained in the resin was 10.7 wt%. This resin showed thermal plasticity below 160°C. The thermal property and solubility of this resin were approximately the same as those of phenol resin. This resin was cured by hexamethylenetetramine. The curing rate was 97.0 wt% at 150°C for 20 min by the addition of 10 wt/ hexamethylenetetramine. The cured resin had higher resistance to acid and alkali than that of the cured phenol resin.
The hydroxymethylation mechanism of the reaction of DPP with formaldehyde was also discussed.

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Methacrylic acid, ethyl acrylate and methyl methacrylate were copolymerized in the presence of -Fe2O₃r by the action of sodium hydrogensulfite in water. The locus of polymerization, the mechanism of coating -Fe2O₃r with copolymers and the interaction between the copolymers and r-Fe203 were investigated. Following results were obtained;
(1) The polymerization of vinyl monomers started in water phase by the oxidation-reduction reaction between HS03- and Fe"- ions.(2) The surface of -Fe2O₃r was coated by the unstable polymer emulsion particles which were formed at the initial stage of polymerization. The copolymers found on the surface of r-Fe203 increased with decreasing stability of polymer emulsion particles.(3) The interaction between copolymers and T-Fe203 was strengthened by methacrylic acid. In this case, copolymers on the surface of r-Fe203 wick could not be extracted with acetone amounted to 0.176 g/g-r-Fe203.

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The reverse osmosis separation of some monoamino monocarboxylic acids was carried out by batch cell under an operating pressure of 20 kg/cm'. G and its temperature of 30°C, using DDS-cellulose acetate membranes.
Taft's polar parameter (E a*), Taft's steric parameter (E E5), and nonpolar parameter (E S*) were correlated with polarity of covalent bond, molecular weight of substituent, and interaction energy of London-van der Waals dispersion force, respectively. As a result, these characteristic parameters which can be applied to only aliphatic amino acids were applied to sulfur containing amino acids, aromatic amino acids, and hydroxy amino acids. As the absolute value of nonpolar effect (w*ES*) obtained from the correlation mentioned above increased, the rejection of amino acid decreased. Also, it was found that there was the correlation between the coefficient (w*) related to E S* and the number of carbon atom contained in a substituent. As a result, w* of aliphatic amino acids having straight substituent and hydroxy amino acids varied as the number of carbon atom, but co* of aliphatic amino acids having branched substituent, sulfur-containing amino acids, and aromatic amino acids varied inversely as the number of carbon atom. These relations were approximated by a firstorder equation.

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The removal of chromium (VI) from the solution in terms of adsorption on coprecipitated silica-titania gel, prepared by homogeneous precipitation method, was investigated. Initial pH of the solution, alkali-treatment of the adsorbent, rate of adsorption, saturated amount of adsorption, elution of adsorbed chromium (VI), and recovery of the adsorbent were discussed. Despite chromium (VI) was best adsorbed at pH of ca.2, the capacity of the adsorbent markedly improved by alkali-treatment and the rate of adsorption became high; the time to reach an equilibrium became short. In this case, saturated amount of adsorption and equilibrium concentration obeyed Freundlich-type adsorption isotherm, x = K. clin, where K=1.92 and 1/n=0.70. The saturated amount of adsorption was 2 mg Cr/g at 1 ppm of equilibrium concentration.
When the alkali-treated adsorbent, after complete adsorption of chromium (VI), was shaken in 1 N NaOH solution, 90% of the adsorbed chromium (VI) was eluted, and the capacity of the adsorbent recovered completely. Even after alternately adsorption and elution six times repeated, function of the adsorbent did not change.

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Self-association of acetamide [1] and benzamide [2] and mutual association of m-aminobenzoic acid and o-nitrophenol [3] and that of m-aminobenzoic acid and p-nitrophenol [4] in dioxane solution have been studied by cryoscopic and ebulliscopic methods. [1] and [2] formed trimer, their association constants being 2.61 and 2.51 at 11.8°C and 2.25 and 2.08 at 101.4°C, respectively. [4] formed 1: 1 association compound, its association constant being 1.12 at 11.8°C and 1.25 at 101.4°C. [ 3 ] formed 1: 1 association compound, its constant being 0.64 at 11.8°C.
From these data, thermodynamic calculations of 4G (Gibbs free energy change), zIS(entropy change), or z1H(enthalpy change) for these association reaction were made.

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Selective catalytic hydrogenation of cyclopentadiene (CPD) to cyclopentene (CPE) with bis(dimethylglyoximato) dipyridinecobalt (II) (Co (Hdmg), py, , dipyridinecobaloxime), which showed more stable catalytic activity than Co (Hdmg), py, as reported previously, was carried out in the Dimethyl Carbitol solution (3.3 x 10-2 mol/l) by continuous feeding of CPD (6.7 x 10-5---'4.2 X 10-4 mol/min) at 40-60°C under bubbling flow (60--300 m//min) of hydrogen. A 45.3 mol/ mol of CPE (per mol of catalyzer) was obtained in the maximum yield, when the hydrogen flow rate and the reaction temperature were 220 ml/min and 40°C, respectively.

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Substituted benzyl ethyl ethers were refluxed with 2, 3-dichloro-5, 6-dicyano-1, 4-benzoquinone (DDQ) in benzene for 3 hrs, to afford substituted benzaldehydes, the corresponding diethyl acetals, and 2, 3-dichloro-5, 6-dicyanohydroquinone (DDQH₂). The reactivities of the ethers were dependent on substituents. When benzyl ethyl ether was refluxed with DDQ in methanol for 3 hrs, benzaldehyde dimethyl acetal was given in 18.3% yield. On the other hand, when benzaldehyde diethyl acetal and DDQ was heated in benzene under reflux a small amount of ethyl benzoate was obtained.

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Several new nitro derivatives of sydnone compounds were synthesized by nitration of the sydnones with potassium nitrate in concentrated sulfuric acid.3-Benzylsydnone gave 3-(mnitrobenzyl)sydonone and 3- (m-nitrobenzy1)-4-nitrosydnone on treatment with 1-2 and 6 eq. moles of the nitrating agent, respectively. The nitration of 3, 4-diphenylsydnone occurred only at the p-position of the 4-phenyl ring. From these results (summarized in Table 1), the 3- and 4-sydnonyl groups are suggested to be electron-attractive and electron-releasing, respectively, showing a duality in electronic effect of the sydnone ring.

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Conditions under which the oxidation rate of nitrogen monoxide to nitrogen dioxide is influenced by the presence of diolefins were studied in a gas chamber. The oxidation rate of nitrogen monoxide was found to depend to on a reaction temperature, kinds, constituents, as well as concentrations of diolefins present and the mole ratio of nitrogen dioxide to nitrogen monoxide. It was expected from this experiment that oxidation rate of nitrogen monoxide was heightened by the atmospheric diolefins.

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