The fluorescence properties of 7-substituted coumarins were studied on the bases of the following two points; energy difference between nπ* and nπ* states (ΔE) and nature of the fluorescent state. The energy difference (ΔE) increases with the increase in electron donating power of the substituent, X. For derivatives with small ΔE the fluorescence yield increases with the increase in ΔE, indicating that nπ* character of the fluorescent state plays an important role in the emission properties. Further increase in ΔE, however, results in the decrease in the fluorescence yield. It was found that this drastic change in the fluorescence yield is closely related to the solvent shift (Δν_solv) of absorption spectrum and is also related to the contribution of charge transfer configuration arrising from electron transfer from styryl to the carbonyloxy group (CT_so) to the fluorescent state. Therefore, it seems probable that the CT_so-character of the fluorescent state is another factor controlling the fluorescence properties of 7-substituted coumarins.

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To discuss the effects of intraparticle diffusion on the gas adsorption process in the pellet, the processes were simulated on thethree cases of adsorption by mass transfers for ( I ) volume diffusion only, (II) surface diffusion only and (III) these two diffusions together. At the same time concentration changes of gas flow were measured for benzene adsorption on alumina pellets at 50°C to obtain the adsorption curves. The volume diffusion coefficient D_Ke was calculated by the pore radius (38 Å) of pellet, the adsorption rate constant k_ads by the adsorption curve for the small particles of the adsorbent and the surface diffusion coefficient Ds by the adsorption curve for the large pellet (Fig.4 and Table 1). The experimental adsorption curves are in good agreement with the theoretical results for both of the cases II and III equivalently as shown in Fig.4. Therefore, it indicates that the volume diffusion can be neglected when the surface diffusion is predominant. This fact might explain well that the adsorption from gas phase by the volume diffusion is very little, because the adsorption concentration becomes high by the surface diffusion and easily reaches the equilibrium state between surface and gas phases in the pore, with the surface diffusion being predominant (Fig.6).

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The effects of temperature and pH on solubility, self-decomposition reaction and mass transfer were studied to grasp the characteristics of ozone in aqueous solution from the viewpoint of water treatment. Regardless of flow rate, the linear relationship existed between concentration of ozone in the feed gas and equilibrium concentration of ozone in aqueous solution, and its proportionality constant (apparent distribution coefficient m) decreased with increase of both temperature and pH. The experimental date on the self-decomposition of ozone was most satisfactorily explained if the reaction was assumed to be of the first order, so that decomposition rate constant (k) increased remarkably with increase of both temperature and pH. The overall mass transfer coefficient (K_L) was affected by the flow rate as well as temperature and pH, and it decreased with increasing flow rate by the interaction of bubbles, increasing with increase of temperature and decrease of pH. The real distribution coefficient (m*) and Henry's constant (E) can be calculated from the apparent distribution coefficient by taking account of the self-decomposition of ozone, so that they become _??_where, a is constant area per unit volume of column, and X is a constant. The values calculated from the equations above satisfactorily agreed with the values previously reported.

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The reduction characteristics of silica supported nickel-platinum composite oxide catalysts were investigated by a thermal analysis method. The catalysts were prepared by an impregnation. The reduction peak of platinum oxide was found at 70°C and that of a mechanical mixture of NiO and PtO₂ was found at 70°C and 240°C. However, the nickel-platinum composite oxide showed a single reduction peak, at a temperature lower than that for nickel oxide. The results suggest that the phenomenon is attributable to hydrogen spillover from Pt (or Pd) to nickel oxide or the formation of a Ni-Pt composite oxide.
The catalytic activity was tested with the hydrogenation of ac etone. The nickel catalyst, when reduced at temperatures higher than 400°C, showed a remarkable decrease in the catalytic activity, while a nickel catalyst with a small addition of PtO₂ (0.01%) showed a considerable thermal stability for the aboye reaction. The catalysts containing 4% or more of PtO₂ showed no catalytic activity wheh they were reduced at temperatures lower than 400°C. However, when reduced at higher temperatures, they showed a gradual increase in the catalytic activity. The gas chemisorption (H₂ or CO) data also indicated a peculiar characteristic similar to the catalytic activity. This peculiarity was considered to be related with the formation and decomposition of the intermetallic compounds of nickel-platinum.

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The reduction characteristics of alumina supported nickel-ruthenium composite oxide catalysts were investigated by a thermal analysis method. The reduction peak of ruthenium oxide was found at 150°C. A nickel-ruthenium composite oxide, low in the ruthenium content, showed a single reduction peak at a temperature lower than that of nickel oxide. The catalytic activity was tested with hydrogenation of acetone. As a general tendency, the catalytic activity increased with the reduction temperature below 400°C, irrespective of the amount of nickel loaded on the catalyst carrier and the amount of ruthenium addition. However, the catalyst, reduced above 400°C, showed a remarkable decrease in the activity.H₂ chemisorption behavior indicated a characteristic tendency, corresponding to the catalytic activity. From consideration of both the amount of H₂ chemisorbed on the catalyst and the current distribution in depth from the catalyst surface, it is concluded that the surface area of exposed metal on the catalyst is decreased by the catalyst diffusion into the carrier as well as sintering of the catalytic metal.

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Temperature programed decomposition of Mo (CO)₆ adsorbed on Bi₂O₃-Al₂O₃ was studied and metathesis reaction of olefin was performed on it. Decarbonylation of Mo (CO)₆ on Bi₂O₃-Al₂O₃consists of two peaks having maxima at around 150 and 320°C. The characteristics of these two decarbonylation processes are quite similar to those on Al₂O₃ except the appearance of a shoulder on the high temperature peak. The low temperature peak is considered to correspond, to a reversible formation of Mo(CO)₃ but the high temperature peak corresponds to an irreversible process accompanied by the oxidation of molybdenum with OH group on alumina of Bi₂O₃-Al₂O₃. It was found that the shoulder part of the high temperature decomposition d id not make an evolution of hydrogen although the oxidation of molybdenum with OH group generated hydrogen. From these results, Mo(CO)₆ adsorbed on alumina of Bi₂O₃-Al₂O₃ is oxidized by the reaction with the OH group on it, but the surface. of Bi₂O₃ does not seem to have such OH groups. The metathesis of propylene was carried out on the Mo(CO) ₆/Bi₂O₃Al₂O₃ catalyst prepared by the evacuation at various temperatures. The catalytic activit y markedly depends on the temperature of the evacuation, and the maximum activity was obtained by the evacuation at about 150°C. This fact results that Mo (CO)₃ formed by the thermal decomposition is effective for the metathesis reaction.

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The sintering behavior and mechanical properties of the alumina-chromia solid solution (chromia concentration: 0∼50 mol%) were studied at low partial pressure of oxygen (P₀₂≈10_-11atm) and in air in the temperature range from 1400 to 1700°C. The sintering behavior was strongly affected by the chromia concentration in the solid solution and also by the partial pressure of oxygen. The sintering characteristics were affected by the addition of small amount of chromia (5 mol%) at both atmospheres. This suggests that the additions of small amount of chromia to the alumina inhibits sintering. At the higher chromia concentration (10∼50mol%), the sintering behavior was complicated. At low oxygen pressure, the high er the chromia concentration, the higher the relative density. In air, the higher the chromia concentration, the lower the final density at 1500 and 1600°C. In contrast, at 1700° in air the whole sintering processes were accelerated, and the behavior was similar to that found in sintering at low oxygen pressure. These results suggest that the solid-state mechanism (s)(volume diffusion or/and grain boundary diffusion) occurs dominantly at low oxygen pressu re and that both the solid-state mechanism (s) and the evaporation condensation mechanism concurrently occur in air. The bending strength of the sintered body changed with its relative density. The relation between strength and porosity obtained for the specimens fired in air satisfied the Duckworth equation for each composition. Hypothetical strengthes of specimens without pore were estimated by extrapolation. Among the estimated strength the highest value was found for the specimen with 20 mol% chromia. When the firing temperature and sintering time were increased, the abnormal grain growth occurred and bending strength decreased.

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Electrical conductivities of the Sm₂O₃-ZrO₂ and Yb₂O₃-ZrO₂ solicl solutions containing 10∼50mol% of each rare earth oxide were measured. The electrical conductivity of the Sm₂O₃-ZrO₂ system decreased and its apparent activation energy increased with increasing Sm₂O₃ content. The structural change from fluorite to pyrochlore phase increased the conductivity, and a conductivity maximum and an activation energy minimum were found at 25∼30 mol% and 30mol% of Sm₂O₃, respectively. However, the Yb₂O₃-ZrO₂ system which does not have pyr ochlore phase showed neither the conductivity maximum nor the activation energy minimum. The ionic transport number of the sample which showed the conductivity maximum (Sm₂O₃: 25 mol%) was measured with an oxygen concentration cell. The ionic transport number was higher than O.9 in a wide range of temperature and partial pressure of oxygen.

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Six sulfanilamide derivatives were precisely determined by the amperometric titration with potassium iodate. The reduction current of iodate ion at a rotating platinum electrode (2000rpm) was measured at a potential of +0.6 V vs. SCE. The method is based on the bromination of sulfanilamide derivatives with potassium iodate in the presence of potassium bromide and the hydrochloric acid (or sulfuric acid). Sulfanilamide (2×10^-5∼10^-3 mol/l), N¹- (6-methoxy3-pyridazinyl) sulfanilamide (2×10^-5∼2×10^-3 mol/l), N'-(2, 6-dimethyl-4-pyrimidinyl) sulfanilamide (2×10^-5∼2×10^-3 mol/l) and 4-amino-N- (5-methyl-3-isoxazolyl) benzenesulfonamide (2×10^-5∼10^-3 mol/l) were determined with the relative error and the coef ficient of variation both less than O.3 %. N1-(2-Pyrimidinyl) sulfanilamide (2×10^-4∼10^-3 mol/l) and N-[4-(2-thiazolylsulfanoyl)phenyl]phthalamic acid (2×10^-5∼2×10^-4 mol/l) were determined with the relative error less than 2% and the coefficient of variation less than 0.2%. The presence of tablet diluents (starch, lactose, magnesium stearate, calcium phosphate and sodium hydrogencarbonate)did not disturb the determination. The recommended procedure proceeded as follows. After 5 ml of 2×10^-3 moli/ sulfanilamide, was introduced into the titration cell, 7.5 ml of 4 moli/potassium bromide, 3 ml of 10 mol/l hydrochloric acid and water were added to make total volume up to 50 ml. The resultant solution was titrated at room temperature with 0.05 ml portions of potassium iodate standard solution at intervals of 10 s. The experimental conditions for other sulfanilamide derivatives are shown in Table 1. Titration time was about 7 min.

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Upon heating p-toluenesulfonamide [1] at 240 260°C for 48 h, di-p-toly1 disulfide [2] S-(p-toly1) p-toluenethiosulfonate [3], di-p-tolyl sulfide [4], p-sulfamoylbenzoic acid [5], ammonium p-toluenesulfonate [7], and ammonium sulfate [8] were obtained as a result of thermal decomposition. p-Toluenthiol [6], toluene [9], and ammonia were also detected. Mechanism for predominant formation of [2] was described. Owing to relatively high stability of [1], extent of pyrolysis was less than 28% under the present reaction conditions. No thermal decomposition occurred below 200°C.

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Tris (2-phenoxyethyl) isocyanurate (TPEIC) was prepared by the reaction of tris (2-hydroxyethyl)isocyanurate with phenol and was found by the thermal analysis techniques to be thermally stable and to have dimorphic crystals depending on the cooling conditions of DTA. No difference in the pyrolytic behavior was observed in these dimorphic crystals. These dimorphic crystals showed marked differences in DTA curves (Fig.5), IR spectra (Fig.6), and X-ray diffraction patterns (Fig.7), however. In the decomposition by electron impact, the molecular ion peak was detected clealy. The fragmentation of a triazine ring was considered to take place after successive cleavage of the three. side chains of TPEIC.

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In order to see the bathochromic shift due to the amino group in benzenoid ring, 1, 4-naphthoquinone derivatives [7a∼e] having the amino groups at 5, 8-positions and the additional substituents (Cl, Br, CH₃, OCH₃, NH₂) at 2, 3-positions have been synthesized.5, 8-Diamino2, 3-dichloro-[7 a], 5, 8-diamino-2, 3-dibromo-[7 b] and 5, 8-diamino-2, 3-dimethyl-1, 4-naphthoquinones [7 c] were obtained by nitration, hydrolysis and reduction of the corresponding 2, 3disubstituted 5-acetylamino-1, 4-naphthoquinones [7a∼c] (Scheme 1).5, 8-Diamino-2, 3-dimethoxy [7 d] and 2, 3, 5, 8-teramino-1, 4-naphthoquinones[7 e] were synthesized by the reactions of 5-acetylamino-2, 3-dichloro-8-nitro-1, 4-naphthoquinone [5 a] with CH₃Na and potassium phthalimide, respectively (Schemes 2, 3). For these compounds in ethanol, UV and visible absorption spectra were measured. The strongest bathochromic effect was obtained for [7 b]which showed the longest wavelength band at 636 nm. The bathochromic and hypsochromic shifts were observed for the derivatives having electron-withdrawing and electron-donating groups at 2, 3-positions, respectively.

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The direct amination of anthraquinone in the presence of butylamine and the rhodium (I)complex was examined in basic solvents. Some methyl-substituted pyridines as solvents enha. nced the yield of 1- (butylamino) anthraquinone [1 a] in the presence of [RhCl (PPh₃)₂]₂ equimolar to anthraquinone. In β- and γ-picolines and 3, 4- and 3, 5-lutidines, the amination product [1 a] was obtained in better yield than in diglyme, while pyridine, α-picoline, quinoline and isoquinoline gave. low yields. Higher basicity and smaller steric requirement of the solvents seem to be preferable for the formation of [1 a] (Table 2). The yield of [1 a] rose to about 50% in β-picoline (3.75 ml) under the following optimum conditions; anthraquinone: 25 mmol/l, butylamine: 2.6 mol/l, [RhCl (PPh₃)₂]₂: 40 mmol/l at 110°C for 10 h in air (Table 3and Figs.1, 2 and 3).
In the reaction of an thraquinone-d₈ with butylamine in β-picoline under N₂, [RhCl (PPh₃)₂]₂ catalyzed a D-H exchange reaction at the α-positions of anthraquinone to afford anthraquinone2, 3, 6, 7-d₄ in 91% yield (Table 4). From these results a tentative reaction mechanism for the amination was proposed (Fig.4).

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Structural changes of melt-quenched poly (ethylene terephthalate) (PET) on annealing have been studied mainly with the infrared spectroscopic method. The structural features of annealed PET are characterized by the trans fraction in the ethylene part and the planarity of the terephthaloyl part. These features are successfully explained from the consideration that the resulting structure is formed through the solid-solid transition from our previously proposed structure for melt-quenched PET. Crystallization at lower temperature (below 200°C) is induced by the local conformational changes of distorted chains and ordering to the more perfectprystalline state at highertemperature (above 200°C) takes place through sliding diffusion of chains which results in the increase of long period. The two-step crystallization can not be explained in terms in the random coil structure for melt-quenched PET.

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2-Diphenylamino- or 2-dibenzylamino-4, 6-bis(p- or m-aminoanilino)-1, 3, 5-triazines reacted with benzophenone-3, 4: 3', 4'-tetracarboxylic dianhydride in N, N-dimethylacetarnide to form solutions of poly (amic acid)s of high molecular wight. These polymers were converted to polyimides by heating at 150°C under reduced pressure. These polyimides are soluble in pyridine, dioxane, epichlorohydrin, m-cresol, tetrahydrofuran, formic acid, sulfuric acid and aprotic polar solvents such as DMA, DIViF, DMSO and NMP. The polyimides with the dibenzylamino substituent are thermally stable to heating up to 360°C, whereas those with the diphenylamino substituent are stable up to 430°C.

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New polyimides containing substituted melamine structure in the main chain were synthesized in N, N-dimethylacetamide by condensing pyromellitic dianhydride with 2- (R-substituted)4, 6-bis. (p- or m-aminoanilino)-1, 3, 5-triazines (R = dicyclohexylamino, 9-carbazolyl, diphenylamino and dibenzylamino). The reaction proceeded in two steps, i. e., the polyaddition and the imidation reactions, similar to the mechanism of polyimide formation. Intrinsic viscosity of the polymers was O.21∼0.62 dl/g. The solubility of the polyimide increased with increasing order of the substituted groups of the 1, 3, 5-triazine ring, show below: dicyclohexylamino>9-carbazolyl>diphenylamino, dibenzylamino.
Thermal decomposition of polyimides having dicyclohexylamino or dibenzylamino group occurred at a side chain but the decomposition of other polyimides both at main and side chains simultaneously.

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New polyimides were synthesized by polymerization of pyromeiitic dianhydride and 2-dialkylamino (R₂N) - 4, , 6 -bis (p-or m-aminoanilino)1, 3, 5-triazines (R=H, CH₃ C₂H₅, CH₂CH₂OH, CH₂CH₂OH₅ and CH₂CH₂CN). The intrinsic viscosity of the polyimides was i n the range 0.18∼0.73 dl/g. The polyimides, which had bis (2-cyanoethyl) amino or bis (2-ethoxyethyl) amino in the 1, , 3, 5-triazine ring, were soluble in acid, aprotic solvents and pyridine. Solubili ty of the polyimide increased with the increasing number of alkyl carbon in the. substituent. When the substituent in the 1, 3, 5-triazine ring had either a lone pair of electrons or no hydrogen participating in hydrogen bonding with other molecules, the polyimide had good solubility.

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The polymerizations of ethyl acrylate initiated thermally by α, α'-azobis (isobutyronitrile)and photo-sensitized by α, α'-azobis (cyclohexanecarbonitrile) have been carried out at 30°C in various aromatic solvents. The thermal and photo-sensitized polymerization rates k_pth and k_pph respectively, changed markedly with solvents and increased in the order: toluene <b enzene<chlorobenzene<bromobenzene<o-dichlorobenzene. The rate of initiation k_i was determined by the inhibitor method using 2, 2-dipheny1-1-picrylhydrazyl as an inhibitor. The initiation rate was practically independent of these solvents in contrast to the change in the values of 2 k_t/k_p². The values of 2 k_t/k_p were obtained by the rotating sector method. The propagation rate constant k_p and termination rate constant 2 k_t were derived on the basis of the values of 2k_t/_p² and 2k_t/k_p. The k_p values changed markedly with the variation of solvents, while the 2k_t values changed a little. The remarkable change of k_p was considered to be dependent on the noticeable change in k_pdue to the interaction between solvents and propagating radicals. The interdependence between 2k_t and the viscosity of solvents could not be found.

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As a change in molecular conformation or in molecular bending property of polyelectrolytes with hydrogen ion concentration was noticeable, polyelectrolyte complexes (PEC) were prepared by mixing [2- (diethylamino)ethyl]dextran hydrochloride (EA) and sodium poly (styrenesulfonate)(NaSS) having especially large bending property at different hydrogen ion concentrations and in different order of dropping.
A coagulation curve of PEC in solution was found to vary in order of dropping. The PEC prepared with a same mole ratio SIN of mixture solution at a termination of coagulation was similar in structure, especially in compOsition ratio of two components, irrespective of an order of dropping, whereas the PEC prepared with a different mole ratio SIN and at a high hydrogen ion concentration showed a high composition ratio SIN in the PEC, and it was found to be similar to that prepared from EA and sodium dextran sulfate (DS), having small bending property reported in the previous paper. The IR spectroscopy, elemental analyses, and solubilities of PEC, revealed that the structure and properties of PEC prepared at a high hydro gen ion concentration, were different from those of PEC prepared at a low hydrogen ion concentration. It appeared that the bonds between SO₃H and OH groups in PEC were formed at a gigh hydrogen ion concentration. Moreover, the molecular conformation of this PEC was found to differ from that prepared from of EA and DS. This would be a change in degree of dissociation of DS and NaSS with hydrogen ion concentration and in difference in the extent of bending property of DS and NaSS.

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The influence of cold-drawing and annealing on α-, β-, and γ-dispersions of Nylon 6 fiber has been investigated. Differences in superstructures among 15 kinds of Nylon 6 fibers which were prepared by various combinations of cold-drawing and annealing exerted influence in a complex manner on the features, the absorption temperatures, and the apparent activation energies of these dispersions. The behaviors of the dispersions were discussed in terms of the previously reported information about the superstructures and the physical and mechanical properties of the fibers which were obtained by the same procedure as this study. The results are summarized as follows.
( 1 ) The peak te mperatrue and the apparent activation energy were most sensitively affected by the history of the fibers in the case of the α-dispersion, and the effect of the history became smaller for β- and γ-dispersions in an ascending order. As the motional units of segments related to a dispersion get larger, the dispersion appears to become more sensitive to the variation of the superstructure.
( 2 ) The intensities of the β-dispersion peak increased by cold-drawing and decreased by annealing. The results can be understood by the assignment that the β-dispersion is due to the movement of the amide groups free from intermolecular hydrogen-bonding.
( 3 ) The intensity of the γ-dispersion peak was dependent strongly on the orientation of molecular chains.

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To obtain a crosslinking agent with high reactivity toward ultraviola ray, dicinnamyl male ate monomer and oligomers have been prepared by the reaction of maleic anhydride with cinnamyl alcohol. Their photosensitivities were examined. Radical polymerizability of clicinnamyl maleate monomer in solution was poor, and average molecular weight of the obtained oligomers was 1000∼1500. Photochemical reaction of dicinnamyl maleate in methanol brought about dimerization of cinnamyl group, and bulk polymerization brought about products: with lactone rings. Addition of a radical polymerization initiator or a triplet sensitizer to dicina myl maleate improved its photosensitivity, but scarcely increased its spectral sensitivity distribution. The photosensitivity of pentaerythrytol triacryiate, one of the typical photocrosslinking agent, was improved by the addition of dicinnamyl maleate. A joining power of dicinnamyl maleate increased but its adhesiveness decreased with UV-irradiation. Upon heating, selective adherence for various toners occurred; it was useful for joining and hardening material to make a portrait.

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Kinetics of: thermal decomposition of manganese(I1) carbonate into manganese(IV) oxide under the conditions of reduced pressure was studied by using vacuum thermobalance, being referred to phase diagrams of Mn-OO₂-O₂ systems.
The pressure in the reaction tube was k ept at ca.10^-4 mmHg and a weight loss was isothermally measured at 623∼698°C. To express a rate of reaction appropriately, a heat transfer, mass transfer, and chemical reaction models were examined. In the case of heat transfer model, the particles packed within the quartz dish were assumed to be a pellet, and the overall rate determining step of the reaction was determined in terms of a heat transfer rate from surrounding to decomposing interface. In the case of mass transfer or chemical reaction m odel the decomposition of the packed particles occured independently due to a distribution of specimoi in a wide space these two cases regarded to be a “shrinking core model”.
The heat transfer and the mass transfer models were not adopted. The chemical reaction model was found to express the overall rate adequately and the chemical rate constant k was determined by this model.

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The reduction of NO with NH₃ and the oxidation of NH₃ CO and H₂ with O₂ were investigated to establish the relations among gas composition, temperature, fractional conversion of each reactant and the reaction scheme in NO-NH₃-CO-H 2-O₂-H₂O-N₂ system. The experiments were carried out by using a flow reactor under an atmospheric pressure and at 550∼1050°C. The composition of inlet gas consisted of NO (0∼1000 ppm)-NH₃ (0∼4000 ppm)-CO (0∼1%; mainly 1000 ppm)-H₂ (0∼1%; mainly 1000 ppm)-O₂(0∼5%; mainly 5%)-H₂0(0, 10%)-N₂and the residence time was 0.37 Ns. The results obtained are summarized as follows.
1) Reaction temperature for both NO-reduction and NH₃-oxidation was low ered by adding CO and H₂; the higher CO and H₂ concentration, the larger their effect. The effect of H₂ was much superior to that of CO. The fractional conversion of NO showed a maximum at a certain temperature which depended on CO or H₂ concentration, and the conversion of ca.80% was attained under coexistence of O₂ of ca.1%, CO and H₂. However, it was generally difficult to obtain the high conversion of NO by adding CO and H₂.
2) The apparent oxidation rate of CO was remarkably promot ed under the coexistence of H₂0. Also, both oxidations of CO and H₂ were considerably accelerated with NO, but wer e inhibited with NH₃.

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Theoretical and experimental investigations have been made by using the oxidation reduction potential (ORP), which is symbolized as E, as a dynamic method to maintain the activated sludge in favourable states. The changes in both ORP and pH were measured by a continuous addition of the dilute hydrochloric acid to the various states of activated sludge slution, i. e. aerobic sludge, aerobic endogenous sludge, anaerobic sludge and sterilized sludge solution. The difference of ORP (ΔE) decreased linearly with that of pH (ΔpH). The slope (∂ΔE/∂ΔpH)was affected only by the states of sludge solution and was expressed as the following equation;
_??_
Where n is an integer, R is the gas constant, T is the absolute temperature and F is the Faraday constant.
The experimental results show that n. was about 2 for the aerobic states and for the sterilized states, about 3 for the endogenous states, about 1 for the anaerobic states. These integers were theoretically deduced by the assumption that the electrode was electrochemically in a state of equilibrium. This dynamic method is highly useful to monitor the states of activated sludge solution.

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Current distribution in an electrolytic cell was measured using the method of rotating double probe electrode (RDPE), in which the current between two points in a solution was detected as an A. C. signal. The results indicated that the plots of the output signal versus the current density gave linear relations when a platinized platinum bipolar RDPE was used for the current with uniform distribution in a copper 00 sulfate solution and synthetic sea water at 25°C(Fig.1 and Fig.2). The current direction was measured within an angular accuracy of ± 6°. The current intensity measured and its direction for the current-flow lines with non-uniform distribution were in agreement with the calculated intensity and direction within an error of 10% and 10°, respectivery, at a rotating speed of 13 rps (Table 1). It was found that the platinized platinum electrode, regarded as a low surface impedance electrode, was much more sensitive and stable than a copper or a silver electrode as a practical reversible electrode.

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The influence of hydrogen treatment on the characteristics of the porous LaNi₅ electrode used for an alkaline hydrogen-oxygen fuel cell was investigated. The anode consisted of a double structure of porous films a thin film of LaNi5 alloy, which was coated with the alloy and Teflon dispersion solution (60% aqueous suspension of poly (tetrafluoroethylene)), at the liquid side was superimposed on the thin film, which was made of Teflon powder and active carbon produced by a hot press, at the gas side. The anode, which was characterized by the current density of 175 mA/cm2 at the overvoltage of 0.25 V and the limited current density of 280 mA/cm2, was obtained by the hydrogen treatment of the electrode made of mechanically grounded LaNi5 alloy for` 3 h at above 200°C under the hydrogen atmosphere.

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Use of silver salt was examined to enhance reliability of the flow injection analysis (FIA) for the chemical oxygen demand with potassium permanganate (COD_FIA⋅Mn). To compare with CO_Dm based on a Japan Industrial Standard, pertinent operating conditions of the FIA were investigated for waste water samples by using D-glucose or lactose as a standard. It has turned out that the most reliable results could be obtained by adding O.05% of silver nitrate into the flow of acidic permanganate solution as a catalyst. Under the proposed conditions, chloride up to 1000 mg⋅l^-1 did not interfere with the determination. The newly proposed FIA method could be successfully applied to industrial waste water samples.

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The cation exchanger was prepared by sulfonation of diphenyl phosphonate-furfural resin and the elution behavior of metal ions on this resin was investigated in HC1 and HCl-acetone solution. The ion exchange capacity of the dry resin in the hydrogen form is at the range of 0.7 to 2.5 meq/g-R, depending on the conditions of sulfonation. At HCI solution, the onl y separations of Cd²⁺ and Pb²⁺ ions are possible by elution with 0.20 moll HCI. At HCI-acetone media, Cu²⁺, Cd²⁺, Zn²⁺ and Pb²⁺ ions were eluted in that order with 0.05 mol/l HCI-80 vol%acetone medium. Cu²⁺ can be separated from Zn²⁺ or Pb²⁺ each by elution with 0.015 moli/HCI-80 vol% acetone medium and so does Cu²⁺ from Cd²⁺ with 0.01 molt/ HCI-80 vol% acetneo medium.

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The melting characteristics of highly-drawn isotactic polypropylene films have been investigated as a function of draw ratio λ by differential scanning calorimetry. In the case of drawn films with 15≤λ<20, two main endothermic peaks appeared in every case and the melting region remained almost unchanged even at various heating rates from 2 to 20°C/min. On the other hand, the melting regions for the films with λ≥20 became much narrower as the heating rate decreased. Then, an extremely sharp endothermic peak, the half width of which was about 0.2°C, was observed at the slowest heating rate. of 2°C/min in the present study. Furthermore, the annealing of the films with 15≤λ<20 increased the height of the higher melting peak but decreased that of the lower peak. The annealing of the films with λ≥20, however, developed markedly the lower endothermic peak and reduced the height of the higher melting peak at the same time.

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Various factors affecting ion permselectivity of a liquid membrane containing dibenzo-30crown-10 as a carrier were studied. Experiment on diffusion of potassium or sodium ion from salt solution to pure water across a liquid membrane was carried out. The complex containing polyether ring of dibenzo-30-crown-10 and potassium ion is steric and stable; this liquid membranehad some characteristic permselectivities. ( 1 ) The greater the ET value of the solvent of this liquid membrane, the greater became a flux and permselectivity. (2) The smaller the ratio of anionic charge to ionic radius, the greater became a flux and permselectivity. ( 3 )An increase in permeability of alkaline metal ions was the following order: Li⁺<Na⁺<Cs⁺<K⁺<Rb⁺.

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