The double resonance technique developed recently facilitates the observations of the nuclear quadrupole resonance (NQR), especially the resonance of below 2 MHz and of low natural abundance. But the double resonance technique is not widely used because of some problems in the method of the adiabatic demagnetization. For the demagnetization, we employed a small elevator mechanism driven by a stepping motor. The stepping motor used has advan- tages that the demagnetization speed can be controlled electronically and that the demagnetiza- tion condition in each experimental cycle is held constant. In order to perform the double resonance experiment automatically, we designed and built a digital pulse generator (Fig.11) with a quartz time base. As a result, the intensity of the free induction decay in each experi- mental cycle i. e. the base-line of the obtained spectrum was stabilized. With the apparatus (Fig.2) we could easily detect nitrogen NQR in several heterocyclic compounds (2-thiouracil, 2, 4-dithiouracil, 2-mercaptobenzothiazole, isatin, etc., see Table 1) whose proton relaxation times of the order of one minute. But this apparatus can not be utilized for samples whose relaxation time is about one second or less. The application of the double resonance technique to samples of short relaxation time may be made by a rapid switching system with an electro- magnet of a superconductor.

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An experiment was conducted for the improvement of wettability of oxygen electrodes with activated carbon. Charcoal activated with ammonia gas at 950° C (activated carbon) was fluorinated in view of the fact that graphite fluoride has low surface energy. Adsorption isotherms of water on the activated carbon and its fluorination products were determined to evaluate change in wettability with fluorination. It was found that water adsorption isotherms for the activated carbon and its low fluorination products were typically S-shaped and that the micropores in these samples play an important role on the adsorption of water. These samples at low relative pressure had adsorption behavior similar to each other and the amount of water adsorbed on the samples was proportional to relative pressure. Significant differences, however, were observed for measured adsorbed volume and heat of adsorption between the activated carbon and its fluorination product. On the other hand, the high fluorination products adsorbed only a small amount of water in the whole range of relative pressure. This hydrophobic phenomenon is due to the low surface energy of graphite fluoride. These results suggest that the activated carbon partially fluorinated will be useful for the improvement of wettability of oxygen electrode with activated carbon.

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It was found that change in interfacial curvature has an influence upon the free energy of, diffuse double layer, especially when a potential difference is applied across the interface such as in the case of electric emulsification. The change in free energy (per cm²), Δ f ^e(C), due to the deformation of double layer with interfacial curvature C was theoretically derived from the Poisson-Boltzmann equation with the Debye-Hiickel approximation. If we assume that interfacial curvature changes under the condition of constant interfacial area, the direction of the change in curvature is governed by the sign of interfacial rigidity G^e(C)=(ð Δ f^e(C)/ð C). For spherical interfaces with G^e< 0, e. g. interfaces of vapor/liquid, mercury/water or water/ oil, this double layer effect causes increase in interfacial curvature. Since emulsification is accompanied by increase in curvature C, it takes in the direction of projection of interface with negative G^e (C). These considerations can be applied to the experimental conditions of electric as well as mechanical emulsification, except the aerosol formation, where the potential drop takes place mainly in the vapor phase, the double layer effect being negligible.

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Relations between concentration of calcium ions and the amount of ions adsorbed (Γ _t) on iron(III) oxide (Fe₂O₃) or on titanium oxide (TiO₂) in solutions containing sodium dodecyltri (oxyethylene) sulfate (R₁₂O(E0)₃SO₃Na), sodium hydroxide, sodium chloride and calcium chloride were studied, in order to know the behavior of alkylpoly (oxyethylene) sulfate ions in hard water. These experiments were conducted under the following conditions; in the presence of definite concentration of R₁₂O(E0)₃SO₃Na and 0.3 mmol/l sodium hydroxide, at an ionic strength of 0.01 and at 25° C. Two kinds of linear increases of Γ _{R12O(EO)3SO3-} and Γ _ca2+ with increase in ratio of calcium ion concentration to the total concentration of cations (C_ca2+/(C_ca2++ C_Na+)) were found for Fe₂O₃ and TiO₂. The values of Γ _Na+ and on the other hand, were much smaller over the whole concentration ratio of C_ca2+/(C_ca2++ C_Na+) (Figs.1, 2 and 3). These results show that the cooperative adsorption of R₁₂O(E0)₃SO₃^- and calcium ions on Fe₂O₃ and TiO₂ takes place in the presence of other ions. Stern charge densities (σ) around Fe₂O₃ or TiO₂ particles were calculated from the obserbed values of Γ_t.Maximumvalues of σwerefoundonthecurvesofσvs.C_ca2+/(C_ca2++ C_Na+)duetothemutualchargecancellationofR₁₂O(E0)₃SO₃^-andcalciumionsonFe₂O₃or TiO₂(Fig.5).

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The interaction of transition metal ions with hydrous SnO₂ surface has been investigated by measuring the amount of H⁺ released from the oxide and the amount of metal ions adsorbed on the oxide surface. Aqua ions Cu²⁺, Co²⁺, Ni²⁺ and Mn²⁺ enhanced the amount of H⁺ released from SnO₂, whereas stable complex ions such as [Fe(phen)₃]²⁺ and [Co (en)₃]³⁺ had very little interaction with the oxide. The relation between the amount of H⁺ released and that of metal ion adsorbed, and the pH-dependence of the relation suggest that the surface interaction is the coordination reaction of aqua-metal ions with the deprotonated surface sites formed in acid-base reactions of SnO₂. The experimental data on the surface complex formation indicate that two surface species are formed with stoichiometric ratios (the deprotonated site/metal ion) of 1: 1 and 2: 1. A correlation was found between the formation constants of the surface complexes and the cor-responding values for hydroxo complexes of metal ions.

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Reductive characteristics of heteropoly acids and their metallic salts were examined in con-nection with their catalytic properties for heterogeneous oxidation. These compounds were prepared by the methods given in refs, 4-7. Reduction of these compounds was mainly carried out in a H₂ (5.72%)-N₂ (balance) flow with increasing temperature by continuous measurement of hydrogen consumption. The results were expressed by Temperature Progra- med Reduction (TPR), the profiles of which were illustrated by the relation between temper-ature and H₂ consumption. As Figs.2-6 show, the reduction of H₃PMo₁₂O₄₀ or its analog (H₄PVMo₁₁O₄₀, H₅PV₂Mo₁₀. and H₄SiMo₁₂O₄₀) occurs only at nigh temperatures (above 450° C), where irreversible destruction of polyanion structure (Keggin structure) occurs. Ag-, Cu-, and Ni-salts, can be reduced at low temperatures (Figs.7, 8) where polyanion structure is not destroyed, as evi- denced from the reproducibility of TPR profile after the reoxidation at 300° C with O₂. As Figs.7, 8 and Table 2 show, the reducibility of the salts is in a following sequence: Ag-salt> Cu-salt> Ni-salt> acid. The degree of the reduction, occurred at the low temper-atures, corresponds to the removal of three oxygens per one anion irrespective of counter cations, which is in agreement with a polarographic result: the polyanion in aqueous solu- tion is able to accept six electrons. When these salts were reduced by CO, the reducibility is found to differ from that of hydrogen (Table 2): Cu-salt> Ni-salt> acid> Ag-salt. The catalytic activities of these com-pounds for the oxidation of H₂ and CO are well correlated to the reducibilities of the com-pounds by the corresponding reducing agents (Table 2 and Fig.10). Based on the results, the possibility of catalyst design was suggested.

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The catalytic activities of Pd ribbons for the hydrogenation of C₂H₄ and for the oxidation of H₂ were markedly increased by chemical pretreatments of the surface of the ribbons such as their thermal oxidation by O₂ and further reduction by H₂. Such a chemical treatment of the catalyst did not noticeably change the surface area and the surface structure of the catalyst. These findings were found to be very similar to those previously observed for Pt. It is suggested that some surface defects serving as active sites for the reactions are generated by these chemical treatments. In the case of the oxidation of CO over fresh annealed-catalysts, an acceleration in reaction was always observed during the reaction. We propose an interpreta- tion that this acceleration period corresponds to the stage of the production of new active sites by the oxidation reaction itself, which is similar to the one proposed by Baddour et al. for the oxidation of CO over supported Pd catalysts.

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The extraction of zirconium chloride from hydrochloric acid solutions has been carried out by benzene solutions of trioctylamine (R₃N) and tricaprylmethylammonium chloride (R₃R'NCl; R=C₈-C₁₀). The complexes, (R₃NH)₂ZrCl₆ and (R₈R'/N)₂ZrCl₆, have been isolated and dried through vacuum evaporation of benzene from organic phases, and investigated by thermogra-vimetry and differential thermal analysis. The complexes and their thermally decomposed pro-ducts have also been examined by both infrared spectrophotometry and X-ray diffractometry. It is concluded that the thermal decomposition of the complexes proceeds in the following sequence: in which t- and m-ZrO₂ represent metastable tetragonal and monoclinic ZrO₂, respectively. The symmetry of these complexes is inferred to be an octahedral structure.

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The mechanism of thermal decomposition of neodymium(III) acetate monohydrate and its anhydrides was studied by TG, DTA, X-ray diffraction, infrared spectroscopy, mass spectro-scopy and chemical analysis. The monohydrate begins to lose its water of crystallization at about 120° C, and the dehydration occurs only in one step. The anhydrous acetate dehydrated below 160° C shows a X-ray diffraction pattern of amorphous nature, crystallization taking place at 170° C to yield the anhydride of stable lower temperature type. The anhydride shows another crystallographic transformation at 220° C, giving the anhydride of stable higher tern-perature type. Both anhydrides of the stable lower and higher temperature types have a strong hygroscopic character, increasing their weigh by about 7-8% in air within several hours, and yields perfect monohydrate. The anhydrous neodymium(III) acetate releases acetone and carbon dioxide in the temperature range of 240-400°C, passing through two intermediate compounds in the course of decomposition, and yields neodymium(III) carbonate oxide as a final product. Both new intermediate compounds are insoluble in water. Presumably they have the same composition as neodymium(III) acetate oxide. The anhydride prepared from neodymium(III) acetate and acetic anhydride by a wet process exhibits a crystallographic transi-tion at 270°C, conventing to the anhydride of higher temperature type mentioned. Both anhydrous nedymium(III) acetates of the stable lower and higher temperature types are of new polymorphs of anhydride, and a heat of transition is given 2.8 kcal/mol.

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The various crystalline forms of alkaline earth metal sulfites were prepared from hydroxides or carbonates of calcium, strontium or barium by heterogeneous reaction. The effect of tem-perature on the form of particles produced was remarkable. Calcium sulfite hemihydrate was obtained as a form of plates, a formless mass, spherical mass and flowery mass depending on the temperature ranging from 10 to 90° C (Fig.1 and 4). In the case of strontium sulfite, granules and a formless mass were obtained. Pillars, granules and a formless mass were obtained in the case of barium sulfite. The crystal size of calcium sulfite hemihydrate prepared from hydroxide decreased with decreasing reaction temperatures. It was revealed that a formless mass was produced when the size of a primary particle was O.4-1 μ m and a spherical mass was produced when the size was about 0.3 μ m. Formation mechanism of the spherical mass was discussed on the basis of the form of reaction products for the Ca. Cl₂-Na₂SO₃ system, a SEM observation of the cross section of the spherical mass and their chemical composition.

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Fluorination of graphite by fluorine gas and characteristic properties of partially fluorinated products were studied by means of X-ray diffraction analysis, ESCA and measurements of heat of wetting and specific resistivity. The partially fluorinated graphite particle consisted of both a fluoride layer near the surface and the inner unreacted graphite. Measurement of crystal lattice strain in the unreacted graphite indicated that a large strain was produced at the reaction interface and gave rise to mechanical destruction even in the unreacted graphite as well as in the fluoride layer. An ESCA spectrum of C l₃ of the sample surface gave three peaks assigned to CF, > CF₂ and -CF₃ groups, and another peak due to the carbon atoms not bound with fluorine atoms. The intensity of the last peak decreased with increasing degree of fluorination of graphite. The heat of wetting of the partially fluorinated graphite in 1-butanol was much larger than that of perfectly fluorinated graphite, owing to the chemical exothermic reaction of the wetting liquid with the fluorine atoms weakly bound to cabon atoms of graphite. The intrinsic heat of wetting obtained by subtracting such chemical exothermic contribution from the apparent heat of wetting was still larger than that of perfectly fluorinated graphite, and it decreased with increasing degree of fluorination of graphite. This might be due to the presence of carbon atoms not bound with fluorine atoms on the sample surface. The specific resistivity of the partially fluorinated graphite was much lower than that of insulating perfectly fluorinated graphite and increased with increasing degree of fluorination. The dependences of ESCA spectrum intensity, heat of wetting and specific resistivity on the degree of fluorination suggested that the direct fluorination of graphite progressed leaving a small quantity of carbon atoms unbound and/or intermediately bound with fluorine atoms, and the remaining carbon atoms were gradually fluorinated with increasing extent of fluorination.

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The Co²⁺-containing γ -Fe₂O₃ with a high coercivity as recording materials consists of two types, cobalt adsorption type and cobalt solid solution type. The incorporation of cobalt into acicular γ -Fe₂O₃ particles was studied morphorogically. The cobalt ferrite grew uniformaly on the surface of the γ -Fe₂O₃ particles for Co-epita γ -Fe₂O₃ obtained by wet coprecipitation (addition I ), while the cobalt diffused into the γ -Fe₂O₃ particles for Co-doped γ -Fe₂O₃ obtai-ned by hydrothermal synthesis(additionII). The coercivity of Co-epita γ -Fe₂O₃ and Co-doped γ -Fe₂O₃ increased with increasing cobalt content. The coercivity of Co-epita γ -Fe₂O₃ was higher than that of Co-doped γ -Fe₂O₃ for the same cobalt content, but increased up to that of Co-doped γ -Fe₂O₃ by means of heat treatment at 300-500° C.

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The copper (II) complexes of N-(1-acetonylethylidene)-m- and -p-aminobenzoic acids [ 5 ], [ 6 ] as well as their methyl esters [ 7 ], [ 8 ] were prepared by the reaction of copper (II) acetate monohydrate with the corresponding ligands in dehydrated methanol and THF media. The composition of these complexes was determined by elemental and thermal analyses and the measurement of molecular weight. The configuration of each complex was investigated from the magnetic and spectral data. The mole ratio of copper (II) to ligand was 1: 2 for the monomeric complexes [ 5 ], [ 7 ]and [ 8 ]. The configuration of the complexes in solid states and in noncoordinative solvents such as benzene or chloroform was square planar for [ 5 ] and perhaps distorted square planar for [ 7 ] and [ 8 ]. The complexes [ 5 ] [ 7 ] and [ 8 ] in pyridine and DMSO media were presumed to form a quinque- or sexa-coordinated ad-duct involving one or two molecules of these solvents. The complex [ 6 ] appeared to have a copper-copper linkage bridged with carboxylato groups as suggested by a subnormal magne-tic moment at room temperature and appearance of coo- vibration. Thus, this complex was assumed to become polynuclear by this linkage. The complex [ 5 ] having the free carboxyl group was easily hydrolyzed with the atmospheric moisture. The mechanism of hydrolysis for [ 5 ] was elucidated from the decomposition products.

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The three possible isomers of [Co (L-orn)₂] i. e., L-trans (O), L-cis (O)-trans (N_a) and L-cis(O)-cis(N_a) and one isomer, DL-cis(O) of [Co(D-orn) (L-orn)]⁺ complex have been prepared by ion-exchange chromatography from the reaction product of L-ornithine and a cobalt(III) complex such as trinitratotriamminecobalt(III). The presence of the LD complex suggests that the conversion of the L-amino acid into the D-amino acid occurred. Isomerization with active carbon of any of the above three isomers of [Co (L-orn)₂]⁺ complex invariably gives mixtures of only the three isomers of [Co(L-orn)₂]⁺ in the ratio of 0.09: 0.57: 0.34 in the order mentioned. Calculation of the strain energy minimization was tried for all the iso-mers. The order of the magnitude of the calculated free energy difference has corresponded to that for the free energy difference obtained by equilibration.

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A method is presented for the determination of traces of tin, based on co-precipitation with thorium hydroxide followed by a flameless atomic absorption measurement. Tin was co-preci-pitated quantitatively with thorium hydroxide and its flameless atomic absorbance was not affected in the presence of thorium. The proposed procedure and the results are as follows: To a sample solution (100-2000 ml) containing 2, -20 μ g of tin is added 1 ml of thorium nitrate solution (10 mg Th/ml) and pH is adjusted to 9 with aqueous ammonia. The precipitate is separated by filtration and dissolved in 10 ml of 2 N hydrochloric acid, and then made up to 100 ml. An aliquot (10 μ l) is injected into the cavity of a carbon tube flameless atomizer. The optimum conditions for the deter-mination of tin were; drying at 20 A (160° C) for 10 sec, ashing at 50 A (700° C) for 30 sec, atomizing at 240 A (2750° C) for 10 sec, an argon flow rate of 1.5 l/lmin and an injection volume of 10 μ l. A linear calibration curve was obtained in the range of 20-200 ppb of tin. Among 41 diverse ions tested, tellurium interfered with the determination when its concentrations were more than 100 times of the tin. The sensitivity for 1% absorption was 1.4 ppb and the coefficient of variations (10 replicate samples) was about 2% in each case. The combined me-thod could be applied to the determination of trace tin in aluminum alloy and brass.

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Extraction behavior of palladium(II) from aqueous oxalic acid solution with trioctylamine (TOA) in benzene was investigated to determine the composition of a complex involved in the extraction. The stoichiometry of the complex was determined by either of the mole ratio method, the method of continuous variation and the slope ratio method. Mole ratios of [oxalate/H(II)] and [TOA/Pd(II)] in organic phase were found to be 2.0 and 2.1, respecti-vely, at a constant mole ratio of 3.42 for [oxalate/Pd(II)] in the aqueous phase. The effect of hydrogen ion concentration on the distribution ratio of palladium(II) was also examined. A slope of the plot of log D vs. pH of the aqueous phase was about -2.0 at the equilibrium. These results suggest that the oxalatopalladate(II) species is associated with two molecules of R₃NH⁺. With respect to the effect of TOA concentration the plots of log D vs. log[R₃N] yield a slope of about 2. O. Based on these observations we come to a conclusion that the extracted palladium (II) species in the organic phase predominantly consists of (R₃NH)₂Pd(C₂O₄)₂.

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Synergistic effect of 2, 2'-bipyridine(bpy) on the extraction of manganese (II) and cobalt (II) with benzoylacetone (Hbza) carbon tetrachloride solution was studied. A remarkable enhance-ment of extraction due to the synergistic effect of 2, 2'-bipyridine for manganese (II) -benzoyl-acetone complex was observed and explained by the formation of an adduct complex, Mn (bza) ₂ (bpy). A similar synergistic effect was noted for the extraction of cobalt (II)-benzoyl-acetone complex at a lower concentration range of 2, 2'-bipyridine, but the effect decreased with increasing concentration of 2, 2'-bipyridine owing to the predominant formation of Co(bpy)²⁺ in the aqueous phase. Based on these observations, the following extraction procedure for the separation of manganese(II) from cobalt (II) was established. Either 5 or 10 ml of the aque- ous solution, which is 0.1 mol/l in sodium chloride, is equilibrated with an equal volume of O.1 mol/l benzoylacetone-0.5 mol/l 2, 2'-bipyridine carbon tetrachloride solution by shaking the mixture for 1 hour. The aqueous phase should yield pH 7.5 after the equilibration. By this process, only manganese(II) is selectively extracted into the organic phase, and it can be stripped into 1 mol/l nitric acid.

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Hydroxyl stretching bands have been recorded for some 3-cyclohexen-1-ols and 1-alky1-3-cyclo-hexen-1-ols in dilute carbon tetrachloride solutions. The 3-cyclohexen-1-ols [1] - [3 ] showed two peaks at 3612-3615 and 3623-3628 cm^-1. In the case of the alcohols with adjacent isopro-pyl group, however, both the trans [ 4 ] and cis isomers [ 5] showed three peaks, each at 3612, 3623, and 3634 cm^-1; 3601, 3623, and 3634 cm^-1, respectively. On the other hand, 1- alkyl-3-cyclohexen-1-ols [ 6 ]-[10] showed two peaks at 3599-3603 and 3616-3619 cm^-1 except for the (E)-1, 3-dimethyl-6-isopropyl-3-cyclohexen-1-ol [11] which had two peaks at 3615 and 3624 cm^-1. These compounds are concluded to be present mainly in half-chair conformation. The con-formation with the equatorial substituent in the homoallylic position is more stable than the conformation with the axial substituent. When the hydroxyl group is forced to exist in the axial position, it interacts intramolecularly with π -electrons of double bond.

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The thermal reactions of 2-pyridone with several N-substituted maleimides gave the 1: 2 Michael and Diels-Alder (MDA) reaction products in addition to the 1: 1 Michael(M) reaction products and the Diels-Alder (DA) adducts. A large variety of DA adducts were obtained and charactarized for N-methyl-2-pyridones. The MDA products were found to be formed by the M reactions followed by the DA reactions. The kinetic analyses gave the following information. The electron-withdrawing N-substitue-nts of the maleimides accelerate the M reactions more than the DA reactions, and give larger product ratio, exo/endo. The activation energies for the DA reactions are 24-31 kcal. mol^-1 which are close to those obtained for retro-DA reactions and become large when polar solvents or acetic acid are used. These abnormal phenomena are attributed to the unique dipole-interac-tions in these reactions.

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The effect of added stabilizers on the photodegradation of polyurethane has been examined in the presence of the singlet and triplet oxygens. The higher the quenching capacity of the stabilizer for the singlet oxygen, the smaller was the rate constant of the photodegradation of polyurethane. The presence of singlet oxygen appeared to play an important role in the pho-todegradation of polyurethane at the initial stage as compared to the triplet oxygen. However, no difference was observed between the singlet and triplet oxygens after prolonged irradiation.

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The photochemical reaction of 2, 4-bis (methoxycarbonylamino) toluene (BMCAT) has been pursued in relation to the coloring of urethane compounds. The photoirradiation was carried out under the bubbling of oxygen or nitrogen with a high pressure Hg-lamp. The Isosbestic point at about 252 nm in absorption spectra and isoemmisive point at about 346 nm in fluorescence spectra were observed in the initial step of the photoirradiation. The photorearrangement reaction occurred systematically in the initial step and formed amino compounds. The irradiated products were separated by solvent extraction, distilltion under reduced pressure and TLC. The products were identified by elemental analysis, IR, UV, MS and NMR. After the prolonged photoirradiation, the color disappeared by the: cleavage of the colored compounds. The presence of oxygen accelerated the reaction rate of photodegradation.

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This paper describes the possibility of optical resolution of _DL-mandelic acid (_DL-MA) amine salts by preferential crystallization procedure. The _DL-MA amine salts of primary amines such as butylamine and aniline, secondary amines such as dipropylamine, diisopropylamine (DIPA), diphenylamine, and dicyclohexylamine were prepared. The salts forming racemic mixture, racemic compound, and racemic solid solution were classified by comparing the infrared spectra, melting point, and solubilities of racemic modifications with those of optically active modifications. The results were as follows. ( 1 ) The DIPA salt formed racemic mixture. ( 2 ) The dicyclohexylamine and the diphenylamine salts formed racemic solid solutions. (3)The butylamitie, aniline, and diethylamine salts formed racemic compounds. The resolutions of the _DL amine salts of diethylamine, DIPA, dicyclohexylamine and diphenylamine. were carried out. As the results it was possible to resolv eonly the DIPA salt. Optical resolution of _DL-MA DIPA salts was studied under the conditions of several temperatures and supersaturations. It was found that the optically active isomer resolved at supersaturation from 116% to 125% had high optical purity. The time course of resolution with several temperatures and supersaturations was additionally studied.

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2-Benzoyl-3, 6-dimethylbenzoic acid [ 1 ] in polyphosphoric acid at 100-130° C gave 6, 12- dimethy1-5-oxo-10-pheny1-9 H-benzocyclooct [8, 7, 6-de] anthracene-11, 10-carbonolactone[ 3 ] and 4, 4', 7, 7'-tramethy1-3, 3'-diphenyl-3, 3'-oxydiphthalide [4] in addition to 1, 4-dimethyl-9, 10- anthraquinone [2] at 100-130° C but gave [2] and [3] only at 150QC. The structures of [3] and [4] were determined on the basis of their MS, IR, NMR and UV spectra and chemical behaviors.

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Focusing on the changes of molecular conformation and molecular bending for polyelectrolytes with hydrogen ion concentration, polyelectrolyte complexes (PEC) were prepared by mixing the mixture of carboxymethylcellulose (CMC) and sulfate of poly (vinyl alcohol) (PVSK) having especially large extent of bending with chitosan at different hydrogen ion concentration and in different order of mixing. The molar ratios of S/N in the PEC thus prepared were estimated to be between 0.40 and 0.91, and the content of CMC in the PEC formed at high hydrogen ion concentration was also found to be less than that formed at low hydrogen ion concentration. It was found that the composition of the PEC was very sensitive to the concentration of hydrogen ion. On the basis of the data of IR spectra, elemental analyses, color reaction with Toluidine Blue, degree of swelling for water, and studies on solubility, the structure and properties of the PEC was found to vary according to experimental conditions. Moreover, the molecular conformation and composition of the PEC was found to differ from that consisting of carboxymethyldextran (CMD), sodium dextran sulfate (DS), and chitosan reported in previous paper (Nippon Kagaku Kaishi, 1979, 127). It seemed to depend upon the degree of dissociation and the conformation of CMD, DS, PVSK and chitosan changing with hydrogen ion concentration and upon the difference of the extent of molecular bending between CMC- PVSK, CMD and DS. In addition, blood tests for antithrombogenicity were done according to Imai's method. Both PEC consisting CMC-PVSK-chitosan and of PVSK-chitosan was found to have an antithrombogenic character.

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The Refractive and reflective indeces of Y₂O₃ sintered pieces were measured. The Y₂O₃ specimens are transparent and have a 100% relative density. A tungsten lamp, sodium discharge lamp or He. Ne laser was used as the sources of light for measuring the refractive indeces. The light from these sources in the wavelength range of 0.44-0.67 μ m was polarized with a Polaroid HN-38 polarizer to obtain Brewster's angle θ. The refractive indeces were calculated from the tan θ equation. A Hitachi infrared spectrophotometer, type 215, was used to measure the reflective indeces of Y₂O₃ specimens. A glass plate with a deposited Al layer on its face was used as the reference material with a 100% reflective index. The N_D of the Y₂O₃ specimens was 1.910 ± 0.006. Furthermore, the relation between refractive index n and wavelength λ (μ m) was given by Cauchy's equation as follows: 9.33 x10^-3 n=1.884+ λ 2 The reflective indeces of Y₂O₃ specimens were 10% between 2.5-8 μ m. The indeces of the specimens, however, decrease at wavelength of more than 8 μ m and reached 3.3% at 13 μ m.

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Fe₂O₃-CuO-Al₂O₃ catalyst was found to be excellent in both activity and stability to heat in NO-CO reaction. A plausible reaction mechanism was tentatively proposed on the basis of informations obtained in a pulse-reaction method. The reason why the catalytic activity was enhanced by the mixing of Fe₂O₃ with CuO was discussed.

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Bis (2, 2'-bipyridine)- and bis (1, 10-phenanthroline)carbonatoruthenium (II) complexes were syn-thesized by refluxing the corresponding dichloro complex in water with traces of formic acid, and passing the solution through an anion exchange column of carbonate form in order to remove chloride ions and to form the desired complex. Both complexes were dark violet, and diamagnetic. Electronic spectra of the complexes in dichloromethane and absorption curves of their crystalline powders were measured. The complexes were found to be nonelectrolytes in dichloromethane. The IR data indicated that the carbonato group in the complexes is coordinated to a ruthenium as a bidentate ligand.

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Semimethylxylenol Blue reacts with zirconium to form a water-soluble red complex. The colored solution has an absorption maximum between 578 and 581 nm and shows a definite absorbance over the pH range from 1.4 to 2. O. The reaction is very sensitive and the sensitivity of the determination is 9.8 x 10^-4 μ g Zr/cm² for log (I/I)=O.001 at 579 nm, and Beer's law is obeyed up to 0.8 μ g/ml of zirconium. Of 44 diverse ions examined, gallium, bismuth (III), hafnium, thorium, iron (III) and fluoride interfere with the determination. But the effect of iron (III) is eliminated with ascorbic acid and the interference from bismuth (III) can be also removed by filtration of its oxide compound precipitated.

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The asymmetric hydrogenation of methyl pyruvate to (+)-methyl -methyl lactate using Pt-C catalyst modified with cinchonidine was studied. Preheating of the catalyst at 200-400° C in hydrogen atmosphere before modification with cinchonidine was found to be necessary for high asymmetric-inducing activity to be acquired. The catalyst thus prepared had high asymmetric selectivity (optical yield=78.7%) in ethanol containing a small amount of cinchonidine.

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6-exo-Acetoxy-exo-isocamphane [ 5 ] was stereospecifically given in 18% yield (GLC; isolated yield was 7.5%) by Bertram-Walbaum hydration of camphene [1].6-exo-Hydroxy-exo-isocamphane [ 6 ] was obtained by hydrolysis of [ 5 ], and 6-endo-hydroxy-exo-isocamphane [ 8 ] was derived by dehydrogenation of [ 6 ], followed by LiAlH₄ reduction. The structures of [5 ]-[8 ] were assigned on the basis of their MS, IR, NMR spectra and their authentic data. Compound [ 6 ] has such elegant odor as nojigiku alcohol [10], but [ 8 ] has an odor like borneol.

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Nitrogenous substances produced by the ozonization of azo dyes [ 1 ]-[ 5 ] in aqueous solution were investigated. Nitrogen gas was found to be the main product. The yields of nitrogen gas, differing from one another due to the variety of dyes, were 65-92% based on the total nitrogen of azo group and pyrazole ring. Only minor amount of nitrate was produced. In the case of [ 2 ] in addition to nitrate, a small amount of ammonium ion was produced. The qualitative analyses of nitrogenous residue after the ozonization by means of spot tests showed the absence of nitrosamine, C-nitroso, nitro, and amine compounds.

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