Cathodic oxygen reduction on poly (tetrafluoroethylene) (PTFE)-bonded electrode in alkaline solution was investigated by means of a current interrupt method. Mixture of carbon and complex oxide of perovskite-type La_0.6Sr_0.4MnO₃ and CaMnO_3-x, was used as electrocatalysts.
The electrochemical activity of PTFE-bonded carbon electrode for oxygen reduction was increased by mixing these complex oxides with carbon material (Fig.5). In the case of La_0.6Sr_0.4MnO₃, however, the activity was decreased gradually by repeating the cathodic and the anodic cycles of the steady state polarization. The complex oxides tested had relatively good corrosion resistivity under cathodic oxygen reduction in alkaline solution. The results of X-ray diffractometry and X-ray photoelectron spectroscopy suggested that the oxygen atom in the lattice of these complex oxides was reduced cathodically to produce oxygen defects at the surface in contact with electrolyte in the course of cathodic oxygen reduction. The specific surface area of carbon powder was decreased by the fabrication to the PTFE-bonded electrode (Table 3). When the surface area loss was approximately 50%, the PTFE-bonded electrode gave the best performance for oxygen reduction without distinction of carbons.

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12-Molybdophosphoric acid (PMo₁₂) in concentrated aque ous solutions decomposes on heating to precipitate molybdenum oxides. The decomposition scheme is explained in terms of Eqs. (6) and (5):
2H₃PMO₁₂O₄₀+6H₂O→H₆P₂Mo₁₈O₆₂ 6(MoO₃·H₂O) (6)
MoO₃·H₂O→MoO₃↓+H₂O (5)
The addition of 1wt%H₃PO₄ to 67wt% PMo₁₂ solution inhibited the formation of precipitates over a period of 3000 h at 70°C, although precipitates were observed when the H₃PO₄ added was less than O.5 wt%. Such a marked effect of H₃PO₄ was elucidated by Eq. (1).
3H₃PMo₁₂O₄₀+H₃PO₄⇔2H₆P₂Mo₁₈O₆₂ (1)
Studies using Raman spectra and ³¹P-NMR spectra revealed 18-molybdodiphosphoric acid (P₂Mo₁₈) was formed from PMo₁₂ via 9-molybdophosphoric acid (PMo₉) as expressed in Eq. (2) and Eq. (3).
3H₃PMo₁₂O₄₀+H₃PO₄+12H₂O⇔4H₃PMo₉O₃₁(OH₂)₃ (2)
2H₃PMo₉O₃₁(OH₂)₃→H₆P₂Mo₁₈O₆₂+6H₂O (3)
Eq. (2) is in rapid equilibrium even at room temperature, while the dimerization of PMo9 (Eq. (3)) proceeds slowly.
On the other hand, 12 -tungstophosphoric acid (PW₁₂) remained unchanged even in the presence of H₃PO₄ at 70°C.
The prohibition of 18-tungstodiphosphoric acid (P₂W₁₈) formation even at elevated temperature can be attributed to stability of PW₁₂ against the degradation into 9-tungstophosphoric acid (PW₉) in strong acidic solutions.

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Equilibrium and kinetics have been studied of the reactions between molybdophosphoric acids and phosphoric acid in concentrated aqueous solutions using ³¹P-NMR and a newlydeveloped ether-extraction method (Fig.1).
The formation reaction (Eq. (1)) of 18-molybdodiphosphoric acid (P₂Mo₁₈) from 12-molybdophosphoric acid (PMo₁₂) and H₃PO₄ was confirmed to be reversible (Fig.2).
3H₃PMo₁₂O₄₀+H₃PO₄ ⇔ 2H₆P₂Mo₁₈O₆₂ (1)
The equilibrium constant (K₁) at 70°C and the heat of reaction (-ΔH₁) were determi ned to be 8.12×10² (mol/dm³)^-2 and 248 kJ, respectively (Fig.3). The initial rate of reaction was formulated by
d[P₂Mo₁₈]/dt =k₁[PMo₁₂]^3/2[H₃PO₄]^1/2
where k₁=0.14dm³·mol^-1·h^-1 at 70°C (Figs.8, 9) and the activation energy=27kJ/mol (Fig.10).
Thus the P₂Mo₁₈ formation mechanism was kinetically demonstrated that PMo₁₂ reacts instantaneously with 1-1₃130₄to form 9-molybdophosphoric acid (PMo₉) which dimerizes into P₂Mo₁₈. The latter reaction was considered to be rate-determining step.
The equilibrium constant (K₃) at 70°C and the heat of reaction (-ΔH₃) for the PMo₉ dimerization reaction(Eq. (3)) were calculated to be 2.0 x 10¹²(mol/dm³)^-2 and 82kJ, respectively (Fig.4). The initial rate of reaction was expressed as follows: -d[PMo₉]/dt=k₃[PMo₉]², where k₃=2.0dm³·mol^-1·h^-1 at 70°C (Fig.6). The equilibrium constant (K₂) at 70°C and the heat of reaction for the PMo₉-formation reaction (Eq. (2)) from PMo₁₂ were derived from the values mentioned above.
3H₃PMo₁₂O₄₀+H₃PO₄+12H₂O ⇔ 4H₃PMo₉O₃₁(OH₂)₃ (2)
2H₃PMo₉O₃₁(OH₂)₃ ⇔ H₆P₂Mo₁₈O₆₂+6H₂O (3)

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Under the mild conditions 1, 4-cyclohexadiene was selectively hydrogenated to cyclohexene by heterogeneous nickel catalysts, Ni(acac)₂-Al₂Et₃Cl₃-phosphinated polystyrene complexes. Two types of phosphine-containing polystyrene beads were prepared; copolymerization of styrene and ρ-(diphenylphosphino)styrene, and phosphination of commercial polystyrene. The results of the hydrogenation were compared with those of the homogeneous system using Ni(acac)₂-Al₂Et₃Cl₃-PPh₃ catalyst. In order to obtain a good selectivity for the hydrogenation, the conditions for the heterogeneous system were desirable to be very similar to those for the homogeneous one. It was noteworthy that the selectivity was good at a low degree of crosslinking and at moderate amounts of phosphine ligands in the polymer, and while it was not so good at high crosslinking. The interesting features observed are discussed in connection with the active species and the active sites.

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Reductions of NO over fresh and aged Pd-rare earth catalysts supported on α-Al₂O₃ were investigated through activity examination, TPD-, and adsorption-measurements of NO. Sixteen kinds of rare earths, including yttrium, were used and NO reducing activities were measured using a simulated exhaust gas under the stoichiometric conditions.
It was found that the NO conversion of Pd-rare earth catalysts at lo wer temperatures were better than that of nonmodified Pd catalyst (Figs.1 and 5). Among the catalysts tested, La, Pr, Nd, and Sm were the most effective components (Figs.4 and 8). Except for Ce, the Pd-rare earth catalysts had better activities and selectivities for the NO-H₂ reaction below 300°C than the Pd catalyst (Fig.10) and FI, reacted with NO more easily than with O₂ (Fig.11). The reason why the Pd-rare earth catalysts had the excellent activity for NO reduction by H₂ is as follows: The amount of NO chemisorption on Pd-rare earth catalysts was higher than that on the Pd catalyst (Table 1) and also, the NO chemisorbed on Pd-rare earth catalysts were dissociated more easily than that on the Pd catalyst (Fig.12).

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In order to provide inorganic polymers with regularly porous structures for catalysis and inorganic ion exchangers, various iron phosphates were synthesized by hydrothermal reactions, and their characteristics have been investigated. (i) Fe_1.0-1.2m_0.8-1.5H_2.1-3.0(PO₄)₂ was obtained from iron (II) chloride and MH₂PO₄ (M=Na, K, NH₄). (ii) FeM(HPO₄)₂ was obtained from iron (III) chloride and MH₂PO₄. (iii) A yellowish brown or grayish green product composed of Fe^IIFe^III(PO₄)₂(OH)₂ and iron oxide hydrate was obtained from FeOOH, H₃PO₄ and (C₃H₇)₃N. (iv) A reaction product between FeCl₃, NaH₂PO₄, NaOH and (C₃H₇)₄NBr( 1: 1.5: 2-3: O.2, 170°C) did not contain the quaternary ammonium salt ad ded as a templating agent. (v) A product obtained under the same conditions as (iv) without (n-C₃H₇)4NBr gave the same X-ray diffraction pattern as the product in (iv), and the c ompositions of these products were identified as Fe^III_1.5 Na_1.5(PO₄)₂·O.7-0.8 H₂O. The treatment of (iv) or (v) with HCl substituted hydrogen ions for sodium ions in the structure. The HCl-treated product was further reacted with (n-C₃H₇)₃N. The primary d-value of the product was changed from 10.0-10.6Å and 9.9Å by these treatments, respectively. The results of thermal analysis (TG, DTA) revealed that the sodium ions in the product were exchanged with hydrogen ions and that amines were attached to the sites.

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Adsorption and desorption behaviors of [N'-(dithiocarboxy)hydrazinocarbonylmethyl]Sephadex (DH-Sephadex) for uranyl ion were investigated. Uranyl ion was quantitatively. collected from 50ml of 1× 10^-5mol·l^-1 test solution over the pH range of 4.6-6.7 by stirr, ing with O.1 g of DH-Sephadex for 30 min at room temperature, even in the presence of 1 x mol'l' of sodium nitrate, sodium chloride or sodium bromide, but it could not be collected from 1×10^-2mol·l^-1 solution of sodium citrate or EDTA. Uranyl ion could also be collected from 1000 ml of 5×10^-8mol·l^-1 test solution by batch method with O.3 g of DH-Sephadex or by passing 500 ml of 1×10^-7mol·l^-1 test solution through the column packed with 0.3 g of DH-Sephadex. However, in the column method, very slow flow rate, 0.1ml·min^-1, of test solution was essential. Uranyl ion was recovered from the DH-Sephadex by dissolving it in hot concentrated nitric acid or by eluting with concentrated nitric acid or 60% perchloric acid.

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Anodic oxidation of 2, 6-dimethylphenol in an alkaline dichloromethane in the presence of bromide ion gave poly [oxy (2, 6-dimethy1-1, 4-phenylene] with high efficiency. 4-Bromo-2, 6-dimethylphenol was isolated from the reaction mixture during the electrolysis. Bromide ion is assumed to serve as a mediator of electro-oxidative polymerization. The mechanism of this polymerization was discussed on the basis of results obtained in the measurements including cyclic voltammetry and double potential-step chronocoulometry.

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In order to elucidate the mechanism of the dehydrogenation of flavanones with DDQ, the reactions have been conducted in dry benzene in the presence of acetic acid or its derivatives. The reaction rates were measured by means of HPLC analysis.
This reaction is second order with respect to the co ncentration of [1] and DDQ in all runs. The apparent second order rate constant, k_{2, a} is directly proportional to the square root of the initial concentration of acetic acid (Fig.3(b)), and its logarithm is also proportional to the acid strengths (pK_a) (Fig.4).
For twelve flavanone derivatives ((1)-(12)) which have various substituents on the C₂ phenyl group, k_{2, a} gave a satisfactory Hammett-type linear free energy relationship using Brown-Okamoto's σ⁺ constant, and it was increased by the electron-donating group and decreased by the electron-withdrawing group.
All experimental results strongly sugg est that this reaction proceeds along the path of two step ionic mechanism and rate-determining stage is a hydride abstraction with quinol cation of DDQ. From the data of activation parameters obtained by Arrhenius plot, it is concluded that the isokinetic relationship applies in this reaction, which proceeds under the control of enthalpy.

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Kinetic resolution of tris (acetylacetonato) cobalt(III) [Co(acac)₃] by cathodic reduction was studied with optically active ammonium electrolytes. The reaction obeyed the pseudo-firstorder rate law. Enantioselectivity was elevated at low applied potential of working electrode and maximized at -1.30 V (vs. Ag/AgCl). It was also dependent on the concentration of the chiral electrolyte. Maximum enantiomer rate ratio (kΔ/kΛ) 1.10 was obtained by using (-)-N, N'-tetramethylenebis (dimethylmenthylammonium) diperchlorate. The efficiency of a pulse electrolysis which involved reduction of [Co(acac)₃] and oxidation of [Co(acac)₂] was also examined with the chiral ammonium electrolytes.

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The direct synthesis of ethylene glycol from carbon monoxide and hydrogen with a cobalt catalyst is described. The reactions were carried out in toluene varying the pressure from 600 to 1800 kg/cm². The major products observed were ethylene glycol, methyl form ate, methyl alcohol and ethyl alcohol. The yield and selectivity of ethylene glycol increased as the reaction pressure increased. It was found that an increase in the partial pressure of carbon monoxide and hydrogen increased the yield and selectivity of ethylene glycol. The glycol formation at 1800 kg/cm² (H₂/CO=-1) showed maximum at about 250°C. Above 250°C the formation of methyl alcohol and ethyl alcohol increased with the increase of temperature. The selectivity of ethylene glycol increased as the amount of the catalyst increased and show ed a maximum at a catalyst concentration of about 180 mmol/l. At higher catalyst concentrations the selectivity of methyl alcohol increased. The rate of ethylene glycol formation decreased with time. It was found that an accumulation of ethylene glycol in the catalyst system diminished the rate of glycol formation.
Phenol was found to be a good solvent for ethylene glycol formation. The reaction mechanism by which the production of the major products can be explained is discussed.

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The racemic structures of ammonium salt of N-acetyl-_DL-norleucine and the _DL-organic ammonium salts have been studied to explore the possibility of optical resolution by preferential crystallization. The _DL-salts employed here were ammonium salt (_DL-AM salt), methylammonium salt (_DL-MA salt), ethylammonium salt (_DL-EA salt), propylammonium salt (_DL-PA salt), isopropyl ammonium salt (_DL-IPA salt), _t-butylammonium salt (_DL-TBA salt), and 1, 1, 3, 3-tetramethylbutylammonium salt (_DL-TMB salt). The free energies of formation of racemate and the binary phase diagrams of melting point indicated that _DL-TBA salt is racemic solid solution at the melting point, and other _DL-salts formed racemic compound. However, it was found by the inspection of infrared spectra of _DL- and _D-AM salts, the solubilities, and the ternary phase diagram that _DL-AM salt existed in conglomerate at around room temperature. The optical resolution of _DL-AM salt was feasible in methanol, ethanol, 1-propanol, and 2-propanol at 10 or 25°C for the racemic solutions with degrees of supersaturation of 110 and 120%, although the stereochemical outcome in methanol was very poor. The optical resolutions by successive preferential crystallizations of _DL-AM salt were also achieved in ethanol at 10°C, and in 1-propanol at 25°C, and the _D- and _L-AM salts with optical purity of over 90% were obtained. The thermodynamic properties of these saturated alcoholic solutions of _DL-and _D-AM salts were also studied. It was possible to regard the ethanol, 1propanol, and 2-propanol solutions as being the regular solution, but it was not the case with the methanol solutions. In the methanol solution, a very strong interaction may exist between methanol and AM salt. The optical resolutions mentioned above suggest that such an interaction in the methanol solution poorly affects the optical resolution of _DL-AM salt.

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Poly[oxy-1, 4-phenyleneiminocarbonyl(3-carboxy-1, 4-phenylene)carbonylimino-1, 4-phenylene](PA) was prepared by a low-temperature solution polycondensation using N, N-dimethylacetamide (DMA) as an organic solvent, and PA films were converted to poly amide-imide (PAI) films by heating. It was difficult to enhance the mechanical properties of PAI films by cold and heat drawing of PA and PAI films at a constant temperature. Therefore, we have applied two treatment methods to PA films
(1) The films were drawn in a DMA/H₂O mixture (50: 50, v/v) at 50°C and the nheattreated under a tension of 29.4 MPa. The values of the breaking energy, the tensile modulus and the strength at break of the 3-fold drawn and heat-treated films (sample [6]) were 19.0 MPa, 7.6 GPa and 0.471 GPa, respectively.
(2) The undrawn films were heat-treated under a tension of 2.9 MPa (Temperature was raised from room temp. to 330°C at the heating rate of 16°C/min. ). The values of the breaking energy, the tensile modulus and the strength at break of the treated films (sample [5]) were 24.4 MPa, 9.7 GPa and O.549 GPA respectively. These values are about 2.7, 3.2 and 3.8 times as large as those of the undrawn PAI films (sample [3]).
The values of the breaking energy and the strength at break of sample [5] were decreased to 12.4 MPa and 0.472 GPa after a hour-heat-aging at 350°C in air. These values are about 2.4 and 3.9 times as large as those of sample [3] treated at 350°C in air. These results showed a high temperature durability of the drawn and heat-treated materials.

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A charge transport in some pyrazolines dispersed in polycarbonate films was studied. Three pyrazolines with the same chemical composition but with different substitution sites for a pendant 1-naphthyl group, namely, 3-(1-naphthyl)-1, 5-diphenyl-2-pyrazoline (pyrazoline [2]), 5-(1-naphthyl)-1, 3-diphenyl-2-pyrazoline (pyrazoline[3]), and 1-(1-napht hyl)-3, 5dipheny1-2-pyrazoline (pyrazoline [1]) (Fig.1), were utilized. The absorption spectra and the photocurrent pectra (Figs.2 and 3) of the three pyrazolines in polymer matrices were examined. The absorption maximum in pyrazoline[2] was located at the longest wavelength of 385 nm. Also, pyrazoline[2] gave the largest photocurrent among three pyrazolines. The drift mobilities of holes in three pyrazolines in polymer matrices were evaluated by use of the conventional time-of-flight method. Pyrazoline[2] gave the largest mobility value when the three pyrazolines were compared at the same applied field (Fig.9). The localization radii of hopping sites were analyzed from the relation between carrier mobilities and the concentration of doped molecules (Fig.10). Pyrazoline[2] gave the largest localization radius of 0.17nm, while pyrazoline[1] and [3] gave 0.12 nm and O.15 nm, respectively.

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2-(4-Acyloxyberizylideneamino)phenanthrenes and 2-(4-acyloxybenzyliden eamino)-9, 10-dihydrophenanthrenes were synthesized and their liquid crystalline behavier were examined. Both substances have a wide mesomorphic range and the mesophase of the former was thermally more stable than that of the latter. The results are shown in Fig.2 and Table 3, 4.

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Permeation characteristics of H₂, He, H₂, CO₂, CH₄ and C₂H₄ were studied by use of six kinds of porous glasses, the pore radii and volumes of which range from 10 to 12 nm and from 0.157 cm³/g to 0.817 cm³/g, respectively. The permeation rate of the porous glass, which has the pore volume of 0.157 cm³/g, could not been measured. The larger the pore volume, remarkably the higher value of the permeation rate. The permeatin rate of H₂ for the glass with the pore volume of 0.817 cm³/g was 1.88 x 10-7 m³(STP)/m². sPa(membrane thickness: 0.5 mm). This value was about 500 times as large as that reported by T. Kameyama et al. The permeation mechanism for the glass which has larger pore volume than 0.4 cm³/g was molecular flow, whereas surface flow was added to molecular flow for the glass with the pore volume smaller than 0.4 cm³/g. The path of the porous glass which had low porosity was very complicated.

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The liquid-phase hydration of acrylonitrile was carried out on the nickel oxide catalysts. The NiO(A) catalyst obtained by thermal decomposition of Ni(OH)₂ in a stream of decarbonated dry air selectively gives acrylamide. On the other hand, the NiO(B) catalyst obtained by thermal decomposition of NiCO₃·Ni(OH)₂ gives the maximum amount of bis(2-cyanoethyl)ether and small amount of ethylene cyanohydrin together with acrylamide. The product distributions on the two NiO catalysts are similar to those of the acid-base-catalyzed homogeneous hydration of acrylonitrile in liquid phase. Therefore, the acid and base properties of the two NiO specimens were examined. The acidic property was observed on the NiO(A)catalyst, while the basic property was found on the NiO(B) catalyst. A good relationship between the catalytic activity including conversion and selectivity and the amount of acid or base on both NiO catalysts was found out.

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The influence of support in using the different sources (commercial ox ides, metal alkoxides, TiCl₄, Ti(SO₄)₂) of metal oxides as supports (TiO₂ (anatase), γ-Al₂O₃) and of the pretreatment of the oxides (evacuation at 773 K) on the activity of Pd catalysts has been studied to find a favorable catalyst for methanol decomposition to H₂ and CO. The pretreatment by evacuation gave somewhat high surface area as well as high catalytic activity in comparison with that by no-evacuation. Catalytic activity (conversion to CO) increased as the surface area of these catalysts increased. The specific activity for TiO₂-support was higher than that for Al₂O₃-support (Fig.1). The catalytic activity was found to be proportional to the degree of dispersion of Pd on both TiO₂ and Al₂O₃ supports (Fig.2).

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The catalytic hydrogenolysis of exo-7-aminobicyclo[4. 1. O]heptane [1], exo-6-aminobicyclo[3.1. O]hexane [2] and their N, N-dimethyl derivatives [3] and [4] was studied in order to investigate the regioselective behavior of the amino and dimethylamino groups on the cyclopropane ring hydrogenolysis. The catalytic hydrogenation was carried out over Pd-C or Raney-Ni in hexane for 24 h at room temperature under atmospheric pressure or at 80°C under 50 kg/cm². The hydrognolysis of the cyclopropane ring occurred exclusively at the adjacent bond of the amino and dimethylamino groups. The hydrogenation of [1] and [2] was accompanied by the reductive alkylation to give secondary amines. A plausible pathway is presented.

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The decomposition of 1, 8-cineol [1] with formic acid in the presence of A-4 and A-5 zeolites afforded predominantly α-terpineol [6]. The decomposition of 1, 4-cineol [2] with trichloroacetic acid in the presence of A-4 zeolite afforded predominantly β-terpineol [4]. The decomposition of [2] with formic acid gave 1-terpineol [7] with high selectivity (90% at optimum).

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T_1s of protons of poly(ribouridylic acid) (poly(U)) were reduced by an addition of Mn²⁺. This phenomenon is considered to be caused by the dipole-dipole interaction between the proton and the electron spin of Mn²⁺. T₁ minima were obtained from the temperature dependence of T₁ of the complex, and the apparent distances between Mn²⁺ and the protons of poly(U) wer e estimated by substituting 1.59×10^-9 s of which value is estimated from the relation that τ^c equals ω_I^-1. But if Mn²⁺ is assumed to bind to N(3), these estimated distances are longer than those which are estimated from Mn²⁺-proton distances presumed from the Dreiding model by the Bloembergen equation. The reason for this result is considered that a part of Mn²⁺ which binds to phosphate group chelates to N(3). It was found that O.28 of Mn2+binds to N(3) from the ratio of T₁ estimated from the Dreiding model to T₁ observed.
τ^c of Mn²⁺-poly(U) complex at each temperature was eatimated from the: ratio of T₁ at each temperature to T₁ minimum. The comparison of these values with the τ^c of poly(U), which is obtained in the absence of Mn²⁺, indicates that the motion of poly(U) becomes slower in the presence of Mn²⁺ than in the absence of Mn²⁺.

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Although t-butyl 2-ethylperoxyhexanoate has been used industrially as an initiator for vinyl polymerizations because of its low risk of explosion, the decomposition rate and its reactivity toward vinyl monomers have not been reported so far.
The rate constants of the first order decomposition were dete rmined in 16 solvents at 60°C. These values increased with an increase in the solvent polarity. The overall rates and the initiation rates of vinyl polymerizations were determined at 60°C. For the polymerization of styrene, the both rates were almost the same as those obtained by the experiment using benzoyl peroxide.

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To manufacture a coal water slurry(CWS) which is combustible without dehydration, a series of nonionic surfactants was synthesized from polyethylenimine (PEI nonionic SAA). Their abilities for the preparation of highly loaded CWS were examined using Tatung coal powder.
The main findings are as follows.
1) Using PEI nonionic SAA, Tatung coal CWS of high coal content (up to 69%) can be prepared (Table 1).
2) When the molecular weight of polyethylene oxide per each side chain becomes about 5000, coal content in CWS becomes maximum (Fig.1).
3) Abilities of O-[poly(oxyethylene)] polyhydric a lcohol to make highly loaded CWS are low (Fig.2).

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