High-Performance Na⁺, K⁺ and Cl- ion selective electrodes (ISEs) are reported. These are based on a new concept, which is an ion recognition site formed by molecular interaction. In the case of Na and K ISEs, crown ether compounds connecting with planar substituents were used as the ionophores. The selectivities depend on the structure of substituents. It is found that the intermolecular interaction of the planar substituent plays an important role on the improvement of selectivity. The selectivities of interactive mono (crown ether) are equal to that of bis (crown ether). It means that ion recognition site like a bis (crown ether) is formed by the interaction of mono (crown ehter)s. In the case of Cl ISE, immobi lized synthetic bilayer membrane with quaternary ammonium salts was used as the ion sensitive mem brane. In the immobilized synthetic bilayer membrane, ordered molecular aggregates is formed. It is f ound that the molecular orientation improved the Cl selectivity. The insufficient selectivity over lipophilic anions can be controlled by addition of aliphatic alcohol. These resulting ISEs exhibit high speed response and long life time, and they are applicable to clinical use which demands both accurate measurement and high speed processing.

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We have studied thermal and acid denaturation of ovalbumin by use of generalized two-dimensional (2D) near-infrared (NIR) correlation spectroscopy. NIR spectroscopy provides unique information about the hydration and structure of proteins which infrared and Raman spectroscopy do not offer. However, there observed a number of bands due to overtones and combination modes in the NIR region, so that spectral analysis in the NIR region is not always straightforward. Thus, we have employed 2D correlation spectroscopy to analyze the NIR spectra. By using 2D correlation analysis we have been able to separate bands due to water and protein amide groups. We have calculated synchronous and asynchronous correlation spectra of ovalbumin aqueous solutions by use of its concentration as the perturbation from 45°C to 80°C at an interval of 2°C and from pH 5.8 to pH 2.4 at an interval of pH 0.2. The 2D correlation analysis have suggested that the sudden change in the hydration around 68°C causes the unfolding process of the secondary structure and that in the acid denaturation the hydration changes markedly around pH 3.0, leading to the gelation. Our studies have demonstrated that 2D correlation NIR spectroscopy holds considerable promise in the studies of hydration and secondary structure change of proteins.

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The effect of added water on structual change in castor oil was studied by a hot wire method. The change in kinematic-viscosity coefficients for anhydrous and hydrous castor oil were measured to evaluate the interaction between water and castor oil molecules.
The kinematic-viscosity coefficient gradually in creases with increasing the water content and reaches the maximum value at 4075 ppm of water. However, with the further increase in water, the kinematicvisocosity coefficient sharply decreases due to the destruction in the liquid structure of castor oil. Eventually, the maximum value is attained at the solubility limit of water in oil.
The ratio of the number of hydroxy groups of glycerol triricinoleate in the castor oil to the amount of water molecule is 5/mol H₂O at the maximum kinematic-viscosity coefficient, where the liquid structure is developed due to the intermolecular crosslinking of water.
However, the crosslinking of water disappears at the solu bility limit of water and a water cluster is formed. In this case, water acts as a kind of a plasticizer and decreases the kinematic-viscosity coefficient.
The liquid sturucture is gradually destroyed at each water content with the rise in temperature from 10 to 50°C and it almost disappears at 60°C.

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Iridium catalysts supported on MFI-type metallosilicates were prepared and their catalytic activity for the selective reduction of NO_x with hydrocarbons under oxygen rich condition was investigated. The as-prepared catalyst hardly reduces NO_x to N2 though it showed very high activity for the hydrocarbon conversion with oxygen. After subjecting the activation treatment in 10%H₂0 N₂ at 700°C, on the other hand, the activated catalyst showed very high NO_x reduction activity. The activated catalyst selectively and efficiently reduced NO_x to N₂ with olefinic and aromatic hydrocarbons at 300-500°C in the stoichiometric to lean conditions.
The characterization by XRD and EXAFS revealed that the Jr species existed in the form of oxide (IrO₂) and metal in the as-prepared and activated catalysts, respectively. In addition, H₂-TPR meas urement showed that the activated catalyst had active oxygen species on the Jr metal surface which was more reactive (reducible) than oxygen species on IrO₂ and bulky Jr metal. It was inferred that the high NO_x reduction activity of the activated catalyst resulted from the presence of the active oxygen spe cies which might react with hydrocarbons to form reactive oxygenated intermediates.

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Adsorption of ammonia vapor to fibrous titanium dioxide hydrate having layered crystal structure was studied. The resulting total yield of adsorption ammonia was 4.26 mmol/g, that was the sum of two kinds of amount, by surface adsorption and by intercalation in the crystal lattice, which could have been distinguished from each other. From the latter value the obtained composition was (NH₄) _1.1H_0.9Ti₄O₉mH₂O, m=1.5T. he product had the same number of NH₃ and larger number of H₂0 mole cules in its chemical formula and larger spacing of layers, in comparison with the similar product by the reacition with ammonia aqueous solution.

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A method was developed for the determination of the compositional fluctuation region in the ternary solid solution of rhombohedral PbZrO₃-PbTiO₃-Pb (Mg_1/3Nb_2/3)O₃ system. The compositional fluctuation region was determined from fluctuation limits of lattice spacing and Curie temperature. The fluctuation of the lattice spacing was determined from the measurement of the dependence of broadening of powder X-ray diffraction peaks on diffraction angle. The fluctuation of the Curie temperature was determined from the width of the peak of dielectric constant at the Curie temperature. Lines of compositions having the lower and upper limits of fluctuations of h00 lattice spacing and Curie temperature were drawn on the ternary diagram. An ellipse region area that touches such compositional lines was drawn. This area was considered to be the compositional fluctuation region.

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The authors synthesized a new type poly (oxymethylene) with a long alkyl group using stearyl alcohol (1-octadecanol) as a chain transfer agent during the polymerization of trioxane. In the case of solution polymerization of trioxane using 1, 2-dichloroethane as a solvent and 1, 3-dioxolane as a comonomer, it was found by gas-chromatographical method that during the polymerization most stearyl alcohol fed to the polymerization system was consumed, and by ¹H-NMR method octadecyl unit was confirmed in polymer. However, there was some difference between the consumed stearyl alcohol and octadecyl unit found in polymer. It was observed that the octadecyl unit in polymer was less than the consumed stearyl alcohol. It was deduced that the low molecular weight oxymethylene copolymer with relatively higher comonomer incorporation was soluble to the methanol, which was used as a washing solvent. In the case of bulk polymerization of trioxane using no solvent, fairly good agreement was observed between the consumed stearyl alcohol and octadecyl unit found in polymer except in the case of high feed of stearyl alcohol.¹H-NMR analysis of the obtained polymer showed that the proton of some methylene of octadecyl group attached to the polymer end shifted to the lower magnetic field compared to that of the free stearyl alcohol. The oxymethylene unit connected to the stearyl group was also observed at 4.87ppm, which proved octadecyl group was surely connected to the poly (oxymethylene) end. t Synthesis of EndGroup Modified Poly (oxymethylene) by Chain Transfer Reaction. Part 1.

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The influence of the state of water on the water vapor permeability through different cation forms of the Nafion® membranes was studied. Two alkali metals (Na and K) and two amino sugars (an equimolar mixture of α-D-glucopyranosyl-(1→6)-2-amino-2-deoxy-α-D-mannitol and its D-glucitol (GPA)and D-glucosamine (GLU)) were used as counter ions. Based on the two state-model, the content and mobility of non-freezing water were determined using DSC and ¹⁷O-NMR. The water vapor permeability of the Nafion® membranes depended on the solubility of water in the membrane while the diffusivity of water vapor through the Nafion®membranes was related to the mobility of non-freezing water rather than water uptake in the membranes. The diffusivity of water through the Nafion®membrane containing GPA was the lowest value in this study because, for the membrane, the fraction of non-freezing water was the greatest and the mobility of non-freezing water was the lowest. The uptake of freezing water in the Nafion® membrane was depressed by the bulky structure of amino sugars and the mobility of non-freezing water around amino sugars was lowered by local aggregation of the hydroxyl group of amino sugars compared to other counter ions.

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The effect of UV irradiation on lacquer tree paint films containing UV absorbents, 2-hydroxybenzophenone and 2-hydroxy-4-octyloxybenzophenone, was investigated and discussed on the basis of reversed micelle structure and the evaluation method for the paint films, which we previously proposed.
The development of UV resistance appeared to be related to the effect on the curing reaction and the degradation was not inhibited on insufficient curing. On the other hand, the suppression effect of absorbents on the degradation was observed for the paint films taking a fully developed, reserved-micelle structure. The curing reaction would be little interfered with the absorbent having a molecular structure like Urushiol.

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Isomerization of erythro-1, 2-dipheny1-1, 2-ethanediol (1a) into threo-la was successfully achieved by treatment with 2 molar amounts of potassium t-butoxide in refluxing THF for 2 h. Monoesters or diester of erythro-la with pivalic acid or benzoic acid were also isomerized into the corresponding threoisomers, when treated with 4 molar amounts of potassium t-butoxide even at room temperature. erythro/threo-Isomerization of 1, 2-bis (4-methoxypheny1)-1, 2-ethanediol and 1, 2-bi s (4-methylphenyl)-1, 2-ethanediol proceeded under the similar conditions but failed for isomerization of 1, 2acenaphthenediol.

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