The authors found that a concentrated aqueous solution of a heteropolyacid (20-80 wt%)exhibits specific functions as a catalyst. The concentrated aqueous solution of a heteropolyacid has been commercially applied for the novel process: the selective hydration of isobutene in mixed butenes to t-butyl alcohol (TBA).
In a concentrated aqueous solution of a heteropolyacid, isobutene is selectively (99.9%)hydrated to TBA at below 80°C (Fig.7) without hydration of 1- and 2-butenes (Fig.8) and dimerization of isobutene (Fig.9), and the hydration rate of isobutene is about 8 times faster than in an aqueous mineral acid solution (Fig.1). When a dilute aqueous solution of a heteropoIyacid or an aqueous mineral acid solution is used for the hydration of isobutene in mixed butenes, neither high selectivity nor high activity of the isobutene hydration has been observed.
The specific functions as a catalyst of the aqueous concentrated solution of a heteropolyacid have been investigated. The study on the kinetics of the selective hydration of isobutene in mixed butenes has suggested that the high activity and the high selectivity of the isobutene hydration can be attributed to the predominant coordination of isobutene and H₂O to a heteropolyanion among isobutene, 1-butene and H₂O (Fig.10).
The authors have found that heteropolymolybdic acids in a concentrated aqueous solution (10 wt% or more) tend to decompose in the reaction conditions to precipitate MoO₃. H₂O, MoO₃or their mixtures (Fig.11). The study of the hydrolytic decomposition mechanism of 12molybdophosphoric acid (PMo₁₂) on heating by 31P-NMR spectroscopy and Raman spectoroscopy revealed that PMo₁₂ is stabilized by the combination of additon of a small amount of H₃PO₄, a slight reduction of the heteropolyanion and an addition of an oxygen-containing substrate such as t-butyl alcohol and tetrahydrofuran, without causing any deterioration of the catalyst activity.

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For the purpose of calibrating the glass electrode in py r i dine, the conductometric and the potentiometric measurements were made for the mixtures of the nitrophenols with the ir tetrabutylammonium salts. A new equation have been derived for calculating the electrol y tic conductivity of ion from the ionic concentrations. This equation was applied to t he experimental values of conductivity in order to obtain more reliable equilibrium constants in these system. It was necessary to take into account the ion pair formation between the homo c onjugate ion and tetrabutylammonium ion, especially in the case of the very weak a c ids such as mono-nitrophenols. The equilibrium constants represented by eq. (3), (4), (6) and ( 18)were determined respectively as given in Table 4. A saturated solution of tetramethylammonium chloride in pyridine was used as the electrolyte solution of the reference electrode for the potentiometric measurement. The r elations between the potential of the glass electrode, E, and log(c_a/c₈), where c_a and c₈ den ote the analytical concentrations of nitrophenols and their tetrabutylammonium salts, respecti v ely, are summarized in Fig.2. The hydrogen ion activity, a(H⁺), in the mixtures of the nitrophenols and their salts was calculated by using c_a, c₈ and the equilibrium constants obtaine d above. The calibration curve in pyridine which pa(H⁺) values are plotted vs. po tential, are shown in Fig.3. A good linear relation was obtained in the mixtures of the nitr ophenols and their salts. The equation-for the calculation of pa(H⁺) from glass electrod e measurements was pa(H⁺)=(352-E)/64, where E was given in millivolts.

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It is known that liquid crystalline molecules can exist with guest molecules in the liquid crystalline state. If the structure of guest molecule is greatly different from that of the host molecule, a small amount of guest molecule disturbs liquid crystalline structure and inhibits the formation of the liquid crystal in the system. Therefore, the formation of liquid crystal can be controlled by structural change of the guest molecules. The photoisomerization of azobenzene molecule was utilized for this structural change. In this study, liquid crystalline molecules of carbonate and azomethine were used and methoxyazobenzene was used as the photoisomerizable molecule. The liquid crystal formation was measured by DSC and polarizing optical microscope. The phase transition temperature of the liquid crystal mixture after the structural change of the photoisomerizable molecule was also meastiied. It was found that the liquid crystal formation of the mixed system could be controlled by the 1.5 h irradiation of 365 nm light at the concentrations between about 5 to 30 mol% of methoxyazobenzene. When the film of this mixture was irradiated by 365 nm light under a masking plate, the masked image was clearly recorded by the isomerization of methoxyazobenzene. The image was observed under cross polarizers of polarizing microscope at liquid crystal temperature. However, this image was not observed at lower temperature because of the crystallization. When this mixture was raised at liquid crystal temperature, the masked image appeared again. Though the memory of the irradiation was preserved, the image became looser because of the diffusion and the reverse photo- or thermal-isomerization.

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Various alkali metal metatungstate hydrates, M¹₆[H₂W₁₂O₄₀]. RH2O ( M: Li⁺, Na⁺, K⁺)were synthesized by Freedman's method. The water content of products was varied by vacuum evaporation. The products were characterized with X-ray diffraction, IR spectroscopy and thermal analysis. The effect of water content on physical properties was investigated. Water vapor pressure was measured by the manometric static method, the proton transport number was determined from e. na. f. measurements and the a. c. impedance method was used for conductivity measurements.
X-Ray diffraction and thermal analys is of M¹₆ [H₂W₁₂O₄₀]. RH₂O with different R values showed there are different water sites in the crystal and that each sites has a specific dehydration temperature. Measurements of proton transport number indicated that the conduction was entirely protonic. The conductivities were 9.25 x 10^-4 for Li₆[H₂W₁₂O₄₀] . 31.9 H₂O and 1.84 x 10^-6 for K₆ [H₂W₁₂O₄₀]. 5.8 H₂O S/cm. The conductivities increased with increasing water content. From these results, it was concluded that water molecules, interacting weakly with alkali metal ions and [H₂W₁₂O₄₀]^6- anions, are main contributors to conduction of M^I₁₆ [H₂W₁₂O₄₀]⋅RH₂O.

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Formation of magnetoplumbite(MP)-type ferrite from β-alumina type ferrite has been investigated in terms of the structural similarity of both ferrites, which have the Mirror plane separating spinel blocks. Ba²⁺- β-ferrite (0.20 K₂O.1.45 BaO.11 Fe₂O₃) and the mixed phase of Sr²⁺-β-ferrite and MP-type Sr-ferrite (0.18 K₂O.1.33 SrO.11 Fe₂O₃) were obtained by immersing K⁺-β-ferrite powder into Ba(NO₃)₂ and Sr(NO₃)₂ melts, respectively, at 650°C. A large portions of these divalent β-ferrites transformed into MP-type ferrite at about 800°C without rearrangement of atoms in the spinel blocks. On the other hand, β"-alumina type Ba²⁺-β"-ferrite (0.02 K ₂O.1.10 B aO5.5 Fe₂O₃), in which the mirror plane is not in the st ructure, transformed into disordered intermediate phase at 700--800°C, and then formed MP-type ferrite at 1000°C. Therefore, the transformation of β structure into MP structure seems to be topotactic reaction based on the structural similarity of β and MP-type structures. This was confirmed using a single crystal; that is, the (001) plane of Ba²⁺-β-ferrite crystal turned into the (001) plane of MP-type Ba-ferrite. However, the single phase formed at higher temperature of 1000°C. Furthermore, the saturation magnetizations of MP-type ferrite obtained from Ba²⁺- and Sr²⁺- β-ferrites were respectively lower than those of normal MP-type ferrite. These would be associated with the residual K⁺ ions in these ferrites.

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Trace amounts of arsenate in medicines and chemical agents were determined by the spectrophotometric detection of molybdoarsenate-Malachite Green (As-Mo-MG) aggregate after preconcentration on membrane filter.
Test solutions were prepared by dissolving the samples in water to give dilute solution (0.01-0.1 mol. dm^-3). The As-Mo-MG aggregate was formed by the addition of t he MoMG reagent (mixed solution of ammonium molybdate and Malachite Green) to the solution. The presence of an adequate arhount of phosphate in the solution was found to accelerate the formation of the As-Mo-MG aggregate. The aggregate collected on a nitrocellulose membrane filter (pore size 3 μm) was dissolved in a small volume of Methyl Cellosolve along with the membrane filter, and the absorbance at 627 nm, A1, was obtained. The value of Al was proportional to the sum of the concentrations of arsenate and phosphate with a molar absorptivity of 2.8 x 10⁵ dm³ mol^-l cm^-1. The absorbance, A2 due to phosphate alone was determined on a separate portion of the test solution by following the procedure after reducing the arsenate to arsenite by thiosulfate. Then the arsenate concentration- was readily given as A1-A2. The calibration curve for arsenate was linear in the range of 0.1-14 nmolf test (γ= 0.998).
The method was applied to the determination of arsenate in 15 medicines and chemical agents such as sodium chloride, glucose and glucose injection. Arsenate at ppb levels was determined in a short time. The analytical recoveries of arsenate in 5 medicines such as glucose, fructose and sodium chloride, were between 92 and 103%. The results were not affected by the presence of Na⁺, K⁺, Cl^- in ca.10⁸ fold excess in these samples.

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For clarification of the photochemical reactivities of 2-pyridones toward ethylenes, quenching phenomena of the fluorescence of 2-pyridones by the ethylenes were measured, and the direct photoreactions between various 2-pyridones and ethylenes were analyzed. It has been found that 2-pyridones are fluorescent unless they have electron-withdrawing substituents and some electron-poor ethylenes quench the fluorescence to give photoadducts. The photoadditions occurred when the quenching constants (kqτ) were 0<kqτ <7.6 and the main products were regio- and stereoselective [2+2]cycloadducts across the 3, 4-positions of 2-pyridones. The reactions were concluded to proceed via exciplexes between the 2-pyri dones and the ethylenes, but to give no adducts when the CT properties of the exciplexes were too large. The main reaction was explained on the basis of MO theory. We also revised some descriptions on the fluorescence of 2-pyridone in our previous report.

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¹H- and ¹³C-NMR spectra of (3-substituted 2-methylpheny1)- and [2-(1-substituted alkyl)phenyl]ferrocenes with a steric hindrance around 2-alkyl group were compared with those of toluene analogues. In (3-substituted 2-methylphenyl)ferrocene, the observed steric perturbation effect on the ipso-carbon chemical shift of cyclopentadienyl ring was similar to that for 1-methyl carbon of the corresponding toluene analogues. On the other hand, in [2-(1substituted alkyl)phenyl]ferrocenes, the steric perturbation effect was larger than that for 1-methyl carbon of the corresponding toluene analogues. The preferred endo conformation containing the interaction between d-electron of the iron nucleus and an a-proton of 2-alkyl group has been proposed. Studies on Ferrocene Derivatives. VI

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A new 1 wt% Ru-0.1 wt%, Cu-SiO₂ catalyst for cyclohexene formation from benzene was prepared by a combination of chemical mixing and spray drying procedure. The combined procedure enabled mass production and cost down to prepare catalysts by changing the catalyst raw material from expensive alkoxides to cheaper cilloidal-sols. The conditions for the catalyst preparation and the hydrogenation reaction were optimized in order to increase cyclohexene yield. As a support of catalyst, snow-tex (C) gave the best result, among the six types of commercial silica-sols, two types of silica-gels dispersed in organic solvent and an alumina-sol The most effective solvent for preparing the catalysts was ethylene glycol and its optimum amount was 2.8 times in molar ratio to silica. When the catalysts were activated under hydrogen at 400°C for 5 h, cyclohexene yield was 34.7%. Next, we investigated non-corrosive additives into the reaction solutions to increase yield of cyclohexene. All the alcohols employed as an additive increased effectively cyclohexene yield except 1naphthol. Among them 1, 4-butanediol (5.0 g) and Benzyl alcohol (0.6 g) were more effective, and cyclohexene was obtained approximately 40% yield. Finally, we studied upon the life of the catalysts by repeating the reaction and refreshment. Cyclohexene yield decreased little by little with increasing of runs. The deactivated catalysts, however, were throughly regenerated having an initial performances by the refreshment as well as the initial activation.

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Oxidation of coal tar pitch, consisting of 92.8 wt% carbon, has been carried out in NaOH solution to find out the optimum conditions for the formation of water-soluble aromatic acids (W. S. A. A. ) and to characterize the oxidation products. In NaOH solutions, W. S. A. A. water-insoluble acids, oxalic acid and CO2, were formed, and the distribution of these products is similar to that in the oxidation of coal. In pure water, however, W. S. A. A. and oxalic acid were little formed. The yield of W. S. A. A. reached maximum at 5 mol /kg H₂O, and decreased with increasing NaOH concentration, from 51 wt% at 5 mol/kg-H₂O to 13 wt% at 25 mol/kg-H₂O (Fig.2). The yield of oxalic acid, however, increased with increasing in NaOH concentration, from 4 C% at 5 mol/kg-H₂O to 15.2 C% at 25 mol/kg-H₂O. The optimum conditions were as follows: 5 mol/kg-H₂O, 538 K, 3 h, 5 MPa O₂. Stirring speed little affected the yield of W. S. A. A. at 5 mol/kg-H₂O (Fig.7). Yield of W. S. A. A. under the condition were about 50 wt%, but more than 30 C% of pitch remained as residue. Carboxylic acids of benzene, naphthalene, biphenyl and a small amount of anthracene were contained in W. S. A. A. (Fig.8 and Table 1). The yield ratio (benzenecarboxylic acids/W. S. A. A.) increased with increasing reaction time, from 0.18 at 0.5 h to 0.51 at 6h.

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2-Bromo-N-(dialkylphenyl)maleimides, 2-methyl-N-(dialkylphenyl)maleimides and 2, 3dichloro-N- (2, 6-dimethylphenyl)maleimide have been prepared and screened antimicrobial activity for various fungi, yeast and bacteria.2-Bromo-N-(2, 6-dimethylphenyl)maleimide and 2, 3-dichloro-N-(2, 6-dimetylphenyl)maleimide showed comparative strong activity. Although other 2-bromo compounds showed weak activity and 2-methyl compounds showed no activity. We have found that substitution of hydrogen atom at 2-position with bromine atom or methyl group decreaseantimicrobial activity, especially for bacteria. N-Benzylmaleimides showed strong activity similar to N-phenylmaleimides, but substitution of hydrogen atom at 2-position with bromine atom, or substitution of hydrogen atom at methylene group with methyl group decreased activity. Some N-phenyl imides have been prepared and screened for antifungal activity using three species of fungi. These compounds showed no activity. The Studies on the Preparation and Antimicrobial Activity of Maleimide Compounds. II.

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The compound known as 12 CaO.7 Al₂O₃ corresponding to Ca₁₂Al₁₄O₃₃ has the possibility of anion substitution. The chemical formula of substitutional solid solution corresponds, to 11 CaO.7 Al₂O₃. CaX₂, where X is hydroxide ion or halogenide ion. In the present report, we investigated the substitution reaction of the fluoride ion between 12 CaO.7 Al₂O₃ and CaF₂. The phases in burned product were identified by mean of X-ray diffraction, and the amount of fluoride ion was measured with an ion-sensitive electrode., It was proved that 12 CaO.7 Al₂O₃ solid solution and CaO were formed by burning of 12 CaO.7 Al₂O₃ with CaF₂ at a temperature of 500°C. The compound 12 CaO.7 Al₂O₃ solid solution indicates 12 CaO.7 Al₂O₃ crystal occluding fluoride ions and the end member is 11CaO.7 Al₂O₃. CaF₂, that is, four fluoride ions are substituted for two oxide ions in the unit cell of 12 CaO.7 Al₂O, (Ca₂₄, Al₂₈O₆₆) as the maximum amount. Subsequently as the burning temperature was raised, 12 CaO.7 Al₂O₃ solid solution liberated fluoride ions gradually and was converted into 12 CaO.7 Al₂O₃. As the equimolecular mixture of 12 CaO.7 Al₂O₃ and CaF₂ was burned, the lattice constant (a₀) of 12 CaO.7 Al₂O₃ solid solution changed continuously. This showed that fluoride ions were occluded in 12 CaO.7 Al₂O₃ crystals and the value of a0 depended on the amount of fluoride ions. The value of a₀ decreased gradually with the rise of temperature between 400 and 1000°C, and then increased above 1000°C. Although 12 CaO.7 Al₂O₃, combined with CaO to form 3 CaO. Al₂O₃ at temperatures above 1050°C, 11CaO.7 Al₂O₃. CaF₂ formed 3 CaO. Al₂O₃ at above 1300°C. According to a quantitative analysis of the fluoride ions, 11CaO.7 Al₂O₃. CaF₂ reacted with CaO after the defluorination. These suggested that 11 CaO.7 Al₂O₃. CaF₂ was more thermostable than 12 CaO.7 Al₂O₃.

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Characterization of volatile organic vapor pollutants in ambient air was studied by comparing concentration ratios of hydrocarbons contained in both ambient air and exhaust gas of gasoline fuelled vehicles. Nine hydrocarbons (C₆-C₇ parafin and C₆-C₈ aromatic hydrocarbons)are usually observed in both ambient air and exhaust gas of gasoline fuelled vehicles. A personal computer program was provided to compare concentration ratios of the nine hydrocarbons between two analysis data and to estimate similarity of the both concentration ratios as an numerical index (SIM), which is defined as average of each difference all concentration ratios of nine hydrocarbons between two analysis data. The concentration ratios of nine hydrocarbons co ntained in exhaust gas of gasoline fuelled vehicles depend on kinds of commercially available gasoline, and slightly changed depending on kinds of vehicle and operating conditions. Averaged concentration ratios of the nine hydrocarbons in exhaust gas measured on various conditions seemed to be representative of typical pattern of exhaust gas of gasoline fuelled vehicles in usual use. An SIM value calculated from gas chromatographic data of a sam ple in the suburban area and the averaged concentration ratios of exhaust gas of gasoline fuelled vehicles was high similarity. This fact shows that the ambient hydrocarbons in this area is mainly originated from exhaust gas of gasoline fuelled vehicles and there are no stationary sources concerning these nine hydrocarbons in this area. On the other hand, an SIM value observed at a downtown in Tokyo showed low similarity, affected by some stationary sources such as printing shop located near the measuring point.

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Ohya-ishi powder contains about 65% by weight of clinoptilolite, a kind of zeolite. The Ohya-ishi may be applied to chemical industry, for example, an adsorbent, etc. for consideration of its mineral composition. Evaluation as adsorben t was carried out on the basis of a liquid phase adsorption procedure using an aqueous solution containing Methylene Blue or ammoniacal nitrogen as adsorbate. A comparative study of thermal characteristics of Ohya-ishi powder has been made to those of clinoptilolite contained as the main component in natural zeolites produced in Itaya district in Yamagata prefecture and in Futatsui district in Akita prefecture as comparative samples. By application of the liquid phase adsorption procedure, we have found the following facts.
(1) The clinoptilolite contained in Ohya-ishi powder had dfferent thermal character istics from those of comparative samples and was poorer in the heat resistance than the ordinary natural zeolite.
(2) Judging from the amount of adsorption of adsorbates, clinoptilolite content of these samples decreases Itaya, Futatsui and Ohya-ishi from the results of aqueous NH₄⁺ solution. And content of clay minerals decreases Itaya, Ohya-ishi and Futatsui from the results of aqueous Methylene Blue solution.
(3) No direct correlat ionship was found between the X-ray powder diffraction intensity and NH₄⁺adsorption capacity of clinoptilolite. However, the liquid phase adsorption procedure is an effective tracing means for more "microscopic" surf ace change, different from the X-ray powder diffraction procedure. Study on the Chemical Utilization of Ohya-ishi Powder. IV.

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Cyclohexanol dehydrogenation and cyclohexanone hydrogenation were performed with suspended noble metal catalysts. The orders of initial dehydrogenation rates, Pd>Rh-Pt>Ru and Rh>Pd-Pt>Ru obtained for the catalysts supported on carbon and alumina respectively, were different from those of hydrogenation. In cyclohexanol the suspende d states of carbon-supported catalysts were stable, with the dehydrogenation activity retained for a long period. The platinum catalysts were the most active for hydrogenation. Contrast between the palladium and ruthenium catalysts observed in the behaviors of dehydrogenation and hydrogenation is particularly interesting for developing good liquid-phase dehydrogenation catalysts.

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The hydrogenation of carbon monoxide has been investigated using Rh₄(CO)₁₂ catalyst in 1-methylpyrrolidine (MPD) solvent at temperatures of 210-270°C and syngas pressures of 500-1800 kg/cm2 (H₂/CO=1). The Rh₄(CO)₁₂-MPD system showed a high catalytic activity for ethylene glycol (EG) formation at a low catalyst concentration. Oxygenated compounds such as methanol (MeOH), methyl formate, ethanol (EtOH), ethylene glycol monoformate, 1-propanol, 1, 2 -propanediol (PD), and glycerol (GL) were formed as the by-p roduct. The selectivity to EG increased as the reaction pressure increased. Increasing reaction pressure increased the selectivity to GL and PD and diminished that to MeOH. Increasing reaction temperature diminished the selectivity to EG and Me0H and increased that to EtOH.

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Lactate dehydrogenase (LDH) activity in human plasma provides useful information for diagnoses of liver and heart diseases. However, LDH in human plasma inactivates during frozen storage. Therefore it is important to use fresh plasma for diagnosis. Sodium glutamate and glycerol are known to exert a cryoprotective effect on purified LDH. These cryoprotectants and sucrose also prevent the inactivation of LDH during extraction and purification processes. This paper deals with the effects of sodium glutamate to prevent the inactivation of LDH in human plasma during frozen storage. Sodium glutamate, glycerol and sucrose were almost equally successful in preventing the inactivation of purified LDH during frozen storage. Sodium glutamate prevented the inactivation of LDH in human plasma during frozen storage at -40°C and during cyclic freeze-thawing. Thus, for diagnosis of liver or heart diseases, it will be possible to store human plasma in a freezer after the addition of sodium glutamate.

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The regeneration of nicotinamide-adenine dinucleotide (reduced form NADH) by the reduction of NAD⁺ with hydrogen gas was carried out in the presence of the hydrogenase from Alcaligenes eutrophus, and the synthesis of 6-phosphogluconate (6-PG) was attempted by a combination of the above system and 6-phosphogluconate dehydrogenase. After 24 h, the conversion of 2-, ribulose 5-phosphate to 6-PG was 57.7% and turnover number of NAD⁺ was 8.2

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Alumina gels doped with polyamine nickel(II) and copper(II) complexes were prepared by the sol-gel technique. The gels were characterized by ESR and optical absorption spectrosco pies, thermogravimetry and magnetic measurement for both complexes to-elucidate the effect of adsorbed water. The nickel(II) complex molecules exist mostly in octahedral arrangement. The axial ligands of the configuration seem to change from the chloride ions to the surface hydroxyl oxygens of alumina gels through the formation of the Al-O-Ni linkage by drying. The copper(II) complex molecules are almost as free in tumbling motion as those in aqueous solutions, but they aggregate gradually and the motion stops with decreasing amount of adsorbed water.

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