The characteristics of organic electrolyte solutions which were prepared by dissolving electrolyte salts into organic olvents, and the application of these solutions to lithium batteries have been studied. Chemical and electrochemical stability and high electric conductivity are required for the electrolyte solutions of lithium batteries. The organic electrolyte solutions of present practical lithium batteries are discussed in terms of the viscosity and dielectric constant of the solvents, ionic association and the other properties. The smooth chargedischarge of lithium electrode in the electrolyte solution is essential in order to develop new rechargeable lithium batteries. The influence of the solvents and electrolyte lithium salts on the cycling behavior of lithium electrode have been investigated and the results are discussed in connection with the reactivity of the solvents, the preferential solvation of the solvent with Li⁺, the influence of coexisting anions, lithium alloy electrodes, etc.

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The enol concentrations of 1-(p-substituted phenyl)-1, 3-butanediones (p-XC₆H₄COCH₂COCH₃; X = Br[1], Cl[2], H[3], NHCOCH₃[4], C₂H₅[5], CH₃[6], OCH₃[7], OH[8], NH₂[9]) in ethanol wered etermined by the use of a modified Meyer's method, and the kinetics and equilibriumo f the keto-enolt automerismin [1]-[9] weree xamined. The rate constants (k₁) for the keto-enol tautomerism and those (k₂) for the bromination to the enol form of [1]-[9] at 0-30°C were calculated as (3.1-0.5)×10^-3s^-1 and 0.1-0.3s^-1, respectively. Althpugh the values of k₁ decreased as the substituents became more electron-donating, the valuesof k₂ were nearly constant regardless of the nature of the substituents. The equilibrium constants (K_E) for the keto-enolt automerism of [1]-[9] were determined to be 36.0-2.4; they decreased as the substituents became more electron-donating. The keto-enol tautomerism follows the Hammette quation, consequentlye, lectron-donating and -withdrawing substituents stabilize keto and enol isomer, respectively. This substituent effect is explained by the resonancee ffect. The thermodynamic pcarameters of [1]-[9], ΔH (-8.4-27.1kJ⋅mol^-1) and ΔS (-9.7- -69.5 J⋅mol^-1⋅K^-1), were marked by small in the case of [1]-[4].

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New type of in-cell sintering anodes for Molten Carbonate Fuel Cell were characterized. The anode tape was fabricated by a tape casting technique. Five samples were fabricated from Ni powder (sample A), Al₂0₃ adsorbed Ni powder (B), Ni-10Cr alloy powder (C), Ni-SrTi0₃ powder (D), and amixture of Ni and Ni plated SrTiO₃ powder (E). The burnout process (i. e. in-cell sintering) was conducted by supplying humidified H₂ and raising the temperature up to 650°C (Fig.2). To test creep endurance, samples were kept under compression 0.3 MPa at 650°C for 1000 h. The thickness and the pore size distributions were measured after the test. The polarization behaviors for H₂ oxidation were also measured (Fig.3).
All samples were sintered under burnout conditions except sample C. The thickness of samples decreased by 3% (sample D) to 65% (sample A) during the burnout process. In the creep test, sample D, C and E showed good endurance to creep, while sample D was not suitable as an electrode because of its high electric resistance. The polarization for H₂ oxidation with sample A, B and E at low fuel utilization (U_f=7% at 200 mA/cm₂) was as small as that of conventional sintered type anodes (Fig.9). At high U_f (-80%), their polarization was by 20-40 mV larger than that of sintered type. These results show that the in-cell sintering anodes would be applicable in MCFC, though further work is required to improve their creep endurance and polarization behavior.

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The structures of two associates G₁, and G₂ composed of 1-hexadecanol (C₁₆0H), octadecyltrimethylammonium chloride (OTAC) and water were examined by X-ray diffraction, electron microscopy and optical microscopy. The associate G₁ appearing at the (C₁₆OH/OTAC) molar ratio below 1.5 formed lamellar structures having a lot of hydrated-water molecules. The associate G₂ appearing at the molar ratio between 1.5 and 3.0 formed two types of bilayer structures which depended on the preparation temperature. The liposome-like vesicular structure with a closed bilayer was formed by the preparation at temperatures above the melting point of the associate G₂. The lamellar structure having a long interplaner spacing (120Å)was formed at preparation temperatures below the melting point of G₂. The results suggest that the associate G₂ consisting of three C₁₆OH molecules and one OTAC molecule, behaves like phospholipids or dialkylammonium salts having two long alkyl groups which easily form bilayer structures.

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In order to obtain hydrogen tetratitanate H₂Ti₄0₉⋅nH₂0 crystals with more active ionexchange ability from acid treatment of K₂Ti₄0₉, the synthesis of K₂Ti₄0₉ was carried out by the hydrolysis of mixed alkoxides solution rather than by the reported melting methods. The ethanol solution of potassium metal, commercial C₂H₅0K or (CH₃)₃COK was mixed with titanium isopropoxide respectively and hydrolyzed slowly by H₂O-C₂H₅OH solution. The influence of the compositions and the conditions for hydrolysis to obtain K₂Ti₄O₉ were investigated. One component of hydrolysis products, KOH, is known to dissolve to a great extent in H₂O-C₂H₅0H solution. However, the composition of hydrolysis precipitates was not much different from the starting solutions.
The exothermal peak for crystallization of the dried precipitates with mole ratio Ti/K=2-3 was observed to be in the same temperature range at about 580°C by DTA. The same intermediate product between amorphous and crystalline one was found to be formed by the calcination at 600°C for 1 h.
All products synthesized f rom C₂H₅OK or (CH₃)₃COK and titanium isopropoxide on these hydrolysis conditions were found to become single-phase crystals of K₂Ti₄0₉ after the calcination at 1000°C for 1h when mole ratio Ti/K=2 in the starting solutions.
The results of X-ray diffraction analysis for synthesized K₂Ti₄O₉ crystals were in good agreement with those of Dion and co-workers except for a small change in the intensity, w hich was considered to be caused by crystalline orientation. Needlelike crystals of length more than 30 μm were found by SEM observation.

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Solvent extraction-ICP atomic emission spectrometry was applied to the determination of thorium in phosphate minerals such as xenotime, monazite and apatite.
Phosphate minerals were treated with hot concentrated sulfuric or nitric acid. After removing insoluble residue by filtration, thorium was extracted with O.05 mol⋅dm^-3 1-phenyl-3-methyl-4-trifluoroacetyl-5-pyrazolone-dibutyl ether at pH O.2. The thorium content in the monazite, xenotime and apatite was found to be 6.8, 0.43 and (0.4-1.5)×10^-3%, respectively.

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Separation of peptides under alkaline conditions were performed using a newly developed “capsule type” column material. Those new type packing materials, silicone polymercoated silica, gels modified with alkyl groups, are for reversed-phase liquid chromato graphy (RPHPLC). Silica gel employed here has an average micropore diameter of 120Å and an average particle diameter of 5μm. Silica gel is covered with a homogeneous silicone polymer film of 7Å in thickness.
The retention time of peptides decreased with an increase in pH. The separation performance for peptides is much better by use of an alkaline than an acidic eluent.
A dilute ammonium carbonate buffer (O.0025M) is useful as an alkalin e eluent in view of the stable baseline, high resolution and high volatility.
The recovery of peptides was higher than 90 percent with an alkaline eluent, while it about 80 percent with an acidic eluent.
The “capsule type” column packing materials can be used in a wide pH range (2-10), with high resolution.

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The equilibria and kinetic aspects of palladiumn(II) extraction from hydrochloric acid by three kinds of alkanal oximes with different alkyl-chain length-dodecanal oxime, decanal oxime and octanal oxime-in toluene, were studied along with the aqueous solubiliti es and the interfacial adsorption equilibria of the extractants. The aqueous solubility of alkanal oximes decreased with the increase of the alkyl-chain length, while their interfacial activities were not affected by the alkyl-chain length of the extractants. From the results of the loading test, palladium(II) was found to be extracted as 1 : 2 Pd : extractant complex with all kinds of alkanal oximes employed in the present study. From the kinetic study, the extraction rate with dodecanal oxime, which is practically insoluble in the aqueous solution and interfacial active, was reasonably interpreted by the interfacial reaction model where the reaction rate is determined by the formation of the intermediate complex at the interface between the aqueous and organic phases.
On the other hand, the extraction kinetics by other two kinds of alkanal oximes with shorter alkyl-chain length and, therefore, with considerable aqueous solubility were explained in terms of the reaction mechanism in which the extraction rate is controlled by the formation of the intermediate complex simultaneously taking place at the interface and in the aqueous phase.

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Most of the bis(methine) type merocyanine dyes (MD) undergo photoisomerization in solution. The purpose of this study is to determine the structure of these photoisomers by means of ¹H-NMR. One of the major difficulties in conformational analysis up to now was too fast thermal equilibration in the systems studied so far. This problem was overcome for the first time by discovering a very slow thermal isomerization in 3-allyl-2-thioxo-5-[2(1, 3, 3-trimethyl-2-indolinylidene)ethylidene]-4-oxazolidinone (NK 1774 ) which made it possible to isolate the photoisomers by recrystallization. Some other new systems were a lso investigated by enriching photoisomers up to 30-60% by exposing the solution to the light followed by quick measurements. The results were consistent in all MD systems investigated. The rotational axis, where the photoisomerizations take place, is the bond which connects the acidic ring group to the =CH-CH= bridge. The isomers with their absorption at a longer wavelength were determined as cis and trans for the component at a shorter wavelen g th. The center axis of the =CH-CH= bridge did not seem to rotate. The conformation around this axis probably keeps trans because the coupling constants of the two bis(methine) protons were 12.6 - 13.5 Hz in all MDs. The great change in chemical shifts of these protons was also of interest. This fact was explained in terms of switching the deshielding effects of the carbonyl group upon one proton to the other in consequence with isomerization. The amount of the deshielding effects upon H_α in cis forms was very large (2.63ppm) compared with the typical values (0.4ppm in acetophenone). Such extraordinary effects would be explained by ionic contributions in the pi-electron system of MD as well as the geometrical preferences.

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The reaction of thiirane with methyl isothiocyanate in DMF gave N-methyl-1, 3-dithiolan-2-imine [1] and 3-methyl-1, 3-thiazolidine-2-thione [2]. The ratio of [1] to [2]. was largely increased by the addition of tertiary amine such as triethylamine, and decreased by addition of the salts such as tetraethylammonium bromide or lithium chloride. In the reaction of thiirane with phenyl isothiocyanate, the main product was N-phenyl-1, 3-dithiolan-2-imine even using lithium chloride catalyst at 120°C, though 3-phenyl-1, 3-thiazolidine-2thione was also formed in 12% yield. Reactions of substituted thiiranes such as methylthiirane with methyl isothiocyanate gave 1, 3-dithiolane-2-thiones in addition to the compounds corresponding to [1] and [2]. Although there are two possible structures concerning the compound corresponding to [2], it was determined to be 5-substituted compound by means of ¹³C-NMR spectroscopy.
The mechanism was presumed as follows : the first step was the formation of 1, 3-dithiojanes and followed by the reaction of 1, 3-dithiolanes with thiirane to give 1, 3-thiazdlidine-2-thiones.

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The rates of oxidation of ethylene with aqueous thallium(III) chloride and thallium(III) bromide were determined by measuring the consumption of Tl³⁺ according to the initial velocity assay. The resultant rate equations are as follows:
TlCl₃; υ₁=k₁ [Tl³⁺]^1.16⋅P_C2H4^0.90⋅[Cl^-]^-1.04 (mol/l⋅min)
k₁=9.90 × 10⁵⋅exp {-15200/RT} (mol⋅cm²/l⋅kg⋅min)a
TlBr₃;υ₂=k₂ [Tl³⁺] ^0.84⋅P_C2H4^0.82⋅[Br^-]^-0.84⋅ μ^0.73⋅[H⁺] ^-0.06 (mol/l⋅min)
k₂=1.55 × 10⁷ ⋅ exp { -19100/RT } (mol²⋅ cm²/l²⋅ kg ⋅ min)
It was concluded that both reactions proceed in accordance with similar rate equations, i. e.
υ=k [ Tl³⁺ ] ⋅ P_C2H4 ⋅ [ X^-]^-1
although other minor side reactions might be additionally included under these experimental conditions, particularly in case of thallium(III) bromide. In other words, the rate of reaction is linearly proportional to the concentration of thallium(III) ion and the concentra t ion of ethylene, respectively, and inversely proportional to the concentration of the halide ion. This equation differs from either of the known equation of oxidation with thallium(III) compounds other than halides and that of similar oxidation with Pd(II), so it suggests that the reactions studied here should have different reaction mechanisms from these known reactions.

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Ethylene was oxidized with thallium(III) bromide in aqueous solution to form ethylene bromohydrin as a major product as in the oxidation with thallium(III) chloride giving ethylene chlorohydrin, but thallium(III) fluoride did not give fluorohydrin.
The oxidation of propylene with thallium(III) chlor ide and thallium(III) bromide resembled that of ethylene in its reaction outline, but the selectivity of halohydrin was found to be lower under the same conditions and an increased amount of acetone was formed. The rate constant for the oxidation of propylene was only 6 to 15 times of that for the oxidation of ethylene.
The authors discussed the reaction mechanism of these oxidations by considering the obtained results together with the kinetic result as well as the comparison with other similar reactions, and proposed the most likely series of reaction routes which comprise the following three steps: the first step of preliminary equilibrium where olefin attacks TlCl₄- complex ion to form the π-complex, the rate determining second step where the π-complex is converted into oxythallation adduct (σ-complex) by water, and the final step where the halogen atom shifts to form halohydrin.
This m echanism is closer to that of the oxidation with palladium(II) than to the mechanism so far considered in the oxidation with thallium(III) and suggests that the difference between the palladium(II) oxdation and the thallium (III) oxidation is not based on the difference in properties between both metal ions, as Henry proposed, but should be attributed to the difference between the halide complex ion system and the other anion system.

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The salt of (S)-4-thiazolidinecarboxylic acid (abbr eviated to (S)-THC) with equimolar (2R, 3R)-tartaric acid, ((R)-TA) crystallized from an aqueous solution containing (RS)-THC and (R)-TA, and (S)-THC with 94-100% optical purity was obtained in 34-73% yield from this salt. From the mother listuor (R)-THC with approximately 100% optical purity was also given in 38-42% yield. The salt of (RS)-THC with equimolar racemic tartaric acid was found to be a conglomerate composed of the (S)-THC ⋅ (R)-TA and (R)-THC ⋅ (S)-TA salts and was optically resolved by successive preferential crystallization at 20°C in water. Recrystallization of the obtained salt from water and the subsequent treatment with ethanol and methanol gave optically pure (R)- and (S)-THC and (S)- and (R)-TA.

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A new method for functional endoscopic examination which employs the measurements of gastric mucosal electrical impedance using an endoscope has been developed. The impedances were evaluated in some kinds of gastric muscosal lesions in the frequency range of 100Hz-100kHz. The levels of the impedance in rats and dogs were measured as basic exami nation. As a clinical examination, the levels of the impedances were examined for 63 patients with gastric muscosal lesions and normal controls.
The Cole-Cole plots were measured correctly both in the animals and human. The ColeCole plot of the patients with gastric cancer was clearly different from that of the controls. The frequency f(X=0), at which the reactance becomes zero, was 10.1±1.2 kHz for cancer patients, whereas the f(X=0) was 14.7±2.7 kHz for the controls. The values of both R(X=0) and (Z) were lower in the cancer patients than those in the controls. However, f(X=0) showed no remarkable difference between the cancer lesions and their surroundings, while R(X=0) in the cancer lesions dropped significantly against that of their surroundings. These results indicate that the measurements of mucosal impedance are very useful in the clinical diagnosis of the gastric cancer.

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1-Ethyl-1-(phenyl, p-tolyl, p-chlorophenyl or p-methoxyphenyl) biguanides were prepared by the reactions of 1-arylbiguanides with ethyl iodide. New isopropenyl-1, 3, 5-triazines, e. g., 2-amino-4- (N-ethyl-p-methyl (6), N-ethyl-p-chloro(7) or N-ethyl-p-methoxy(8) anilino) 6-isopropeny1-1, 3, 5-triazines were prepared from 1-aryl-1-ethylbiguanide with met h acryloyl chloride. The homopolymerization of these monomers and their copolymeriza tions with styrene and methyl methacrylate (M₁) were carried out using azobisisobutyronitrile as an initiator in dimethyl sulfoxide. The copolymerization parameters (r₁, r₂, Q₂ and e₂) were determined for these monomers. The relationships between the glass transition temperatures of these copolymers and composition of the copolymers were investigated. Thermal polymerization of (6) - (8) was studied by differential scanning calorimetry (DSC). The ceiling temperature (TV_C) and the heat of polymerization (ΔH_p) were obtained from DSC data. The values of T_C and ΔH_p of (6) - (8) were 161 - 167° and -10.8 - -11.2 kcal/mol, respectively.

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Styrene macromonomers differing in molecular weight we re copolymerized with 2-hydroxyethyl methacrylate (HEMA). Cast films of the graft copolymers dissolved in DMF were prepared on surface of Hg. The surfaces of films on Hg and air sides showed hydrophilic and hydrophobic properties below 80-90 wt% of HEMA. The critical surface tensions from the Zisman plots and the surface free energies calculated from the harmonic mean equation increased with an increase in HEMA content and a decrease in the molecular weight of macromonomers. The distribution of polar groups from the surface to bulk of films was investigated from ESCA. The concentration of the polar groups, especially OH groups, of the film surface which had been in contact with Hg was very high in the vicinity of the first surface layer. However, it decreased with distance from the surface and remained constant in the inner layer. Therefore it can be concluded that some polar groups in the graft copolymers in solution migrate to orient towards the Hg surface and are more concentrated in the first surface layer region than in bulk of the films formed after the evaporation of DMF, determining the hydrophilicity of the surfaces.

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It has been generally accepted that the viscosity of a poly (vinyl acetate) (PVAc) emulsion depends on its composition and its polymerization process. It has also been shown that, even if the polymerization procedure for vinyl acetate (VAc) as well as the degree of polymerization and the degree of saponification of poly (vinyl alcohol-vinyl acetate) (P(VA-VAc))used as a surfactant are kept constant, PVAc emulsion shows different viscosities when different kind of P(VA-VAc) is used.
The causes of this difference in the viscosity of PVAc emulsion were investigated.
1) One of the causes is the sequence distribution of acetoxyl group of P(VA-VAc). The longer the sequence length of acetoxyl group, the higher the surface activity of P(VA-VAc)results in.
The s equence length of acetoxyl group increases with decreasing the dielectric constant of the solvent, in which the saponification of PVAc is carried out.
Typical examples of such solvents are benzene and acetone in methanol. In these media, the saponification is found to be accelerated by the action of sodium hydroxide nearby the hydroxyl groups generated by the reaction. For this reason, the sequence length of acetoxyl group becomes longer.
2) Chain branching: In the case of PVAc which is obtaind by emulsion or suspension polymerization, chain branching is the major factor for making the resulting P(VA-VAc)highly active as a surfactant, and this gives a high viscosity of PVAc emulsion.

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The saturated magnetization( σ ) of the ferrite sludge formed by ferrite process treatment of wastewater containing heavy metals was measured over a wide range of dilution ratio ( f ) (ex. when the heavy metal concentration rate of the experimental liquid waste to the origin al one is 1/10, f=10) of wastewater, and the effects of heavy metal ion concentration on the wastewater treatment by ferrite process were discussed quantitatively.
The dilution ratio dependence curves of saturated ma gnetization for various heavy metal ions except Zn are similar to each other and shift along the dilution ratio axis with a kind of heavy metal ions (Figs. 2 and 4). The curves have the slope of 1.0 at low f region, 2.6 at middle f region and approach σ(=92 emu/g) of Fe₃0₄ with increasing f, asymptotically. Through the measurement of the X-ray diffraction pattern, it was found that the rapid decrease of a with decreasing f resulted from the formation of hydroxides and/or by-products in ferrite process (Fig.2 and Table 2). The desirable σ of the ferrite sludge, precipitated in the wastewater treatment, is above 60 emu/g for the magnetic separation, the stability of the process, the effective use and the applications of the sludge and the safe disposal of the treated water (Fig.2 and Table 3).

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Photochromism of 1, 1, 3-trimethyl spiro [indoline-2, 3'-naphth[2, 1-b] [1, 4]oxazine] and corresponding three N- (higher alkyl) derivatives (alkyl=C₈H₁₇, C₁₄H₂₉, C₁₈H₃₇) in solutions and in solids was studied. The absorption spectra of four compounds at their thermal equilibrium, those after UV-irradiation and the rates of thermal fading of colored species were measured. The long alkyl substituents moved the thermal equilibrium between colored and non-colored species towards colored states. In nonpolar solvents, the association of colored species was suggested. The thermal decays of colored species proceeded in a first-order kinetics in solutions, and in a nonpolar solvent, it became slower with increase of length of alkyl chains. The T_g values of glassy films were largely dependent on the length of alkyl chains. Above the T_g, photochromic behaviors were very similar with these in solutions. But below the T_g, non-first-order thermal decays characteristics to glassy states were observed.

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The preparation method of polycondensed fused-polynuclear aromatics (COPNA) film was studied using naptharene(N), anthracene(A), phenanthrene(Ph) and pyrene(Py) as fused aromatic hydrocarbon and 1, 4-benzenedimethanol as crosslinking agent. Properties of resulting COPNA films were studies mainly on effects of the fused aromatic hydrocarbon used as raw materials.
Inso luble and infusible COPNA, films were obtained by heating oligomer films at 120-400°C, which were prepared by casting" method using the each oligomer (M_n=1500-1900)/CHCl₃ solution.
Changes of structure and weight of COPNA films were observed scarcely until 400°C. Films from the aromatics except phenanthrene gave the characteristic flourescence spectrum of the each excimer. From results of measurement on their properties, it was found that COPNA films were characterized by a good heat resistance and a high modulus; density 1.15-1.23g/cm³, tensile strength 30-70 MPa, Young's modulus 1.5-2.5 GPa, thermal degradation temperature 440-500°C.
Making a comparison of COPNA films, following orders were obtained on their properties; tensile strength N (30MPa) < A < Ph < Py⋅Ph (70 Mpa), Young's modulus A (1.5 GPa) < N < Ph < Py⋅Ph (2.5GPa), thermal degradation temperature A (440°C)<Py⋅Ph ≤ N = Ph (500⋅).

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Combustion of 1, 2-dichlorodthane, a model compound of harmful volatile chlorinated organicsw, asc arried out on various metal oxide catalysts using an ordinary flow reacto under atmospheric pressure. Transition metal oxides of the first series in the periodic table exhibited high combustion activity, producing a large amount of carbon dioxide and molecular chlorine. As molecular chlorine is reactive, its formation is undesirable in view, of possible production of even more harmful chlorinated by-products. On the other hand, the reaction on acid catalysts such as silica-alumina and titania-silica and on base catalysts such as calcium (II) oxide resulted in incomplete combustion with high yields of carbon monoxide and hydrogen chloride. Most of the oxides suffered chlorination by molecular chlorine or hydrogen chloride and their combustion activity changed during reaction. Especially basic oxides such as calcium (II) oxide reacted with these inorganic chlorines quite easily. However, silica alumina was not attacked by the inorganic chlorines and hence was free from poisonin g by them. Therefore, the following multiple procedure was proposed for the combustion of volatile chlorinated organics. Chlorinated organics are first decomposed by acid catalyst s mainly to hydrogen chloride and carbonaceous moiety. The resultant hydrogen chlo ride as well as molecular chlorine are trapped effectively by basic oxides such as calcium (II) oxide, and, finally, the carbonaceous residues will be converted to carbon dioxide completely by combustion catalysts such as transition metal oxides.

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The maximum of the decoloration rate of the dye 2-(m-substituted phe nylazo)phenoI-4sulfonic acids in pH 8.0 region by the reaction with ozone could be accounted for by the proton dissociation equilibrium (_??_) of the two ionic species of the dye and by the discrepancy between the two pseudo-first-order rate constants (k_obsd(for HD^n-1)>k_obsd(for D^(n+1)-)) that were estimated for the ozone decolorations of these two ionic species. The time dependences of the compositions of the ozone oxidation products of the dyes were also discussed. The bromo and chloro substituents of the dyes were decomposed easily to Br^- and Cl^- ions, respectively. The sulfo substituent was also converted to SO₄^2-. In these reaction s, the final organic product was shown to be oxalic acid.

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The hydrogen isotope-exchange reaction between each of th e two kinds of solid amines, 'sodium iminodiacetate and sodium glycinate, and tritiated water vapor has been obse rved at 50-80°C. Following results were obtained on the basis of A″-McKay plot of the data from the observed activity.1) The acidity of amines can be expressed in terms of the acidity based on a kinetic logic. 2) The acidiy increases with an increase in temperature. 3) The acidity of amino group is 1.5-1.9 times higher that of imino group. 4) The ratio of acidities of several functional groups and compounds can be expressed as follows; (-OH) : (-COOH) : (MHPO4) : (-NH₂) : (=NH) =10²: 10¹ : 1 : 1 : 1, where M is Ba, Sr, Ca, and Mg, respectively.

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The azodye, SOT-Red 2 G (Hodogaya Chemical Co.), which is used in dye transfer thermal printing system, interacts with poly (vinyl alcohol), (PVA). The Hildebrand plot measured by visible absorption spectra gave the equilibrium constant of 2.77l/mol. The Scatchard plot suggests that the dye binds to PVA cooperatively.
Addition of SOT-Red 2 G to DMSO solution of PVA increases the solution viscosity. This indicates that SOT-Red 2 G makes an intermolecular cross-linking junction between PVA chains. The infrared spectra indicate that azo group of the dye binds to OH group of PVA with hydrogen bond. The dynamic viscoelastometry also indicated that PVA chains are intermolecularlly cross-linked in the presence of the dye molecules.

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The temperature(T) dependence of the cholesteric pitch(P) in the solutions of poly[(L-leucine)co-(γ-benzyl L-glutamate)] and poly [(L-alanine)-co-(γ-benzyl L-glutamate)] was investigated under the following conditions;( 1 ) The system is in thermodynamic equilibrium to obtain the value of time-independent pitch; ( 2 ) The system is in anisotropic single phase not including isotropic or gel phase. The solvents used were m-cresol, 1, 4-dioxane and N, N-dimethylformamide (DMF). Concentration of the copolymers was all determined to 0.250g per 1cm³ solvent. Two functional forms were assumed for the analysis of experimen tal data obtained. Both plots of 1/P vs. T and 1/P vs.1/T are shown in Figs. 1 and 2respectively. We calculated the standard deviation from the straight line obtained by the least-squares method (Table 1).
The results are summarized as follows. ( 1 ) In the solutions of m-cresol and of 1, 4 dioxane, 1/P was linear against 1/T in the variety of the copolymers. ( 2 ) In the solution of DMF, however, both plots mentioned above deviated extremely from the straight line.

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