Thermodynamic quantities for the transfer of tris (1, 10-phenanthroline) iron (II) perchlorate from water to a mixed solvent were determined by solubility measurements, The standard free energies of the transfer were divided into the electrostatic components which consist of a change in dielectric constant and non-electrostatic part. The quantity of the latter was related to the standard free energy of the transfer of phenanthrene which can be a model compound for the chemical interaction of the complex with the solvents. The unusual behavior of the complex in solubility can be ascribed to the high contribution of the chemical interaction b etween the aromatic constituent of the ligand and the solvent molecules. The partial mo lar volumes of tris(1, 10-phenanthroline)iron(II) chloride in the mixed solvents were interprete d in terms of the structure of the bulk solvent and the hydrophobic nature -of the ligand.

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The removal of Cl- contained in α-Fe₂O₃ powders has been studied by heating in air with addition of 0.4∼1.4 vol% SO₂ in the temperature range from 20°C to 500°C for 0.5∼2.0 h. The amount of Cl- contained in α-Fe₂O₃ was effectively decreased to 0.044% in the case of heating at 150°C for 1.0 h in air containing 0.4 vol% SO₂ (Fig.1). The chloride ion was replaced by SO₂ in two stepwise processes in which the molar ratios of Cl- to SO₂ were 1.5and 0.3 (Fig.2). The replacement reaction appeared to be retarded by water originally contained in α-Fe₂O₃ and to be accelerated by water added to air for heating. Most of the replaceable Cl-, which was otherwise extractable with water almost completely, existed on the surface of α-Fe₂O₃. The rest of Cl-inside, the crystals could be removed only by the procedure shown in the present investigation (Table 1).

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Conversion of isobutyric acid at 350°C over the phosphorus-promoted MoO₃ catalyst (13/Mo, 1/10 atom ratio) was 77.5% when it was prepared by calcination at 300°C in air. However, the conversion decreased to 59.9% and 26.1% when prepared by calcination at 400°C and 500°C, respectively. The selectivity for the formation of methacrylic acid was close to each othe r, i. e., 44.5% and 42.7 %, over the former two catalysts, respectively; but it was as low as 28.4% over the last (Fig.2 and Table 1). Structural analyses for these three catalysts by means of X-ray diffraction and IR spectroscopy revealed that ammonium dodecamolybdophosphate was formed in the catalyst calcined at 300°C. However, it was also revealed that a small portion of ammonium salt formed was decomposed to MoO₃ when heated at 400°C with the catalyst calcined at 500°C which was composed of MoO₃ (Fig.3 and Table 2). The arsenic-promoted MoO₃ catalyst, which had dodecamolybdoarsenate structure, also showed relative ly high activity and selectivity as compared with those of the antimony and of the bismuth-promoted MoO₃, catalysts which had no heteropolymolybdate structure (Table 3). Therefore, it is concluded that the strong promotional effect of phosphorus as well as of arsenic on the MoO₃ catalyst is not attributed to the special properties of Va group elements but to the formation of dodecaheteropolymolybdate compounds. This conclusion agrees well with the findings previously reported. The highest activity and selectivity for the phosphorus-promoted MoO₃catalyst was observed at P/Mo=1/12 atom ratio; the catalyst produced methacrylic acid with a highest yield of 41.1% at 350°C (47.5% selectivity) and at a highest selectivity of 59.0% at 300°C (21.3% yield), respectively (Figs.4 and 5). The mechanisms of a redox cycle of the catalysts and of the oxidative dehydrogenation are also studied, and the participation of the terminal lattice oxygen bonded to molybdenum ion in the catalytic reaction as well as the formation of methacrylic acid and acetone through an identical intermediate are discussed.

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ZnO-TiO₂ containing no sulfate ion was prepared by a coprecipitation method. Samples were calcined at 550°C in air before theiruse. The amounts of chemisorption of pyridine and CO, were measured by a gravimetric technique using a quartz balance, and the amounts ob tained were taken as the amount of acid or base.
The formations of ZnTiO₃, Zn₂Ti₃O₈ and Zn₂TiO₄ were observed by X-ray diffraction analysis. However, a part of ZnO and TiO₂ in the mixtures was considered to be amorphous. On the basis of these results, the composition of the ZnO-TiO₂ binary system was estimated (Fig.2). The BET surface area of ZnO-TiO₂ (molar ratio, 50: 50) was larger than those of ZnO and TiO₂ (Fig.3). The amounts of acid and base per unit surface area showed maxima at ZnO-TiO₂ (85: 15) and ZnO-TiO₂ (15: 85) respectively (Figs.5 and 6). IR spectra of pyridin e and NH3 chemisorbed on TiO₂ and ZnO-TiO₂ (85: 15) indicated that the acidic sites formed by mixing were Lewis-type (Figs.7 and 8). The formation of basic sites was not observed in ZnO-TiO₂ containing sulfate ion. The conversion of O_2- to Brönsted-type acidic sites by withdrawing a proton did not occur on the surface of ZnO-TiO₂ (15: 85). The formations of acidic and basic sites were explained on the basis of the hypothesis proposed by Tanabe et al.

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In order to elucidate the effect of molecular structure of organic metal complexes on the dark- and photo-conductivity, organic metal complexesw ith imidazole or 2-substituted imidazo les (substituent = m ethyl, heptadecyl, phenyl) were prepared by mixing ethanol solution o f bivalent metal (M (II) = Fe, Co, N i, Cu, S n, Hg) chlorides and ethanol or acetone solution of imidazo le c ornpounds. The crystals of imidazole metal complexes showed octahedral or tetra4edral struct ure. The number of ligands in the complexes was four or six in the case of octahedral structure and usually four in that of tetrahedral one. The conductivity of imidazole complexe s was in the following order; Fe>Co>Ni. It increased with decreasing second ionization potential o f a metal. The photocurrent was weak under an irradiation of visible light. It was suggeste d that the 'major carrier of photocurrent was an electron on the basis of an irradiated polarity effect of an electrode.

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The electrolytic decomposition of aqueous hydrogen bromide was experimentally studied for the development of the bromine-based thermochemica 1 water decomposition cycles. The reversible potentials of both hydrogen and bromine electrodes (E_H2, E_Br2) were determined from the e. m. f. measurements and their overpotentials on a smoothed Pt electrode were also measured in concentrated aqueous solutions of HBr at 25, 35, and 50°C, respectively.
E_H2 shifted linearly to noble potentials with an increase of the molality of HBr (m_HBr) due to the increase of the mean molal activity coefficients and was higher than 150 mV (vs. SHE)in the azeotropic solution of HBr (Table 1, Fig.3). As supposed from the Nernst equation for bromine electrode, E_Br2 became less noble with increasing m_HBr or with decreasing mi, (Table 2, Fig.5). The theoretical decomposition voltage of HBr was about 700 mV or less than that in its azeotropic solutions containing dilute Br₂, at anode.
The current-potential relationship of hydrogen evolution reaction at a Pt cathode clearly followed the Tafel equation with a slope of 30 mV/decade (Table 3, Fig.6). The hydrogen overvoltages were less than 100 mV at 100 mA cm-2, but, the additional increases of the overvoltages due to evolving hydrogen bubbles were observed at higher current densities.
The bromine electrode reaction at a Pt anode proceeded almost reversibly and a linear polarization curve was obtained in the range of current density below 100 mA cm-2 (Fig.7). The limiting current density was not observed up to 1000 mA cm-2 in a stirred solution. The bromine overvoltage decreased with increasing mHBr and was considerably smaller than that of hydrogen in the azeotropic solutions of HBr containing Br₂.

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Graphite fluoride (CF)n is decomposed to form perfluorocarbons and a kind of amorphous carbon which is usually called a residual carbon. When the residual carbon is fluorinated, (CF)n with a high crystallinity can be prepared even at low temperature as com pared with other carbon materialso. This paper describes the studies on the structure and physicochemical properties of the residual carbon by ' means of X-ray diffractometry, Raman spectroscopy, thermo-gravimetry and differential thermal analysis. In addition, the effect of its structure on the fluorination process is discussed.
(1) The residual carbon is extremely amorphous as it has a very small Lc value. However, it has a three-dimensional structure partially. Most of carbon atoms in the residual carbon constitute the hexagonal network, though the stacking of network is random.
(2) Fluorination of the residual carbon is of reaction-controlled eve n at temperature as low as 250°C. The graphite fluoride prepared from the residual carbon has a higher crystallinity than that from other amorphous carbons. Fluorination at temperatures higher than 300°C leads to a decrease in the yield of (CF)n because of the thermal decomposition of (CF)n formed. The thermal decomposition in the course of (CF)n formation can be depressed by gradual heating.
(3) It is unnecessary to use highly oriented graphite in order to obtain (CF)n, with high crystallinity. Carbon with a large layer plane and random stacking of layers is suitable for the fluorination, yielding easily (CF)n with high crystallinity.

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Nitridings of 60 Nb-40 Ti (wt%) alloy powder (grain size is nearly 80μm), Nb-Ti alloy plate (Nb: 20, 40, 60, 80 wt%) and 50 V-50 Nb (wt%) alloy plate specimens with N₂ (1 atm) atmosphere were carried out at 700∼1350°C. The nitriding processes were investigated by microscopic observation, X-ray diffractometry and X-ray microprobe analysis and the possibility of composite nitride formation was discussed. In the nitridings of Nb-Ti alloys, Ti-rich nitride precipitated as needle-like crystal remaining nitrogen poor Nb-rich nitride or alloy. But Tirich nitride and Nb-rich nitride (or alloy) phases reacted to form (Nb, Ti) N as nitriding proceeded further. In the nitridings of 60 Nb-40 Ti powder and Nb-Ti plate (Nb: 20, 40, 60, 80wt%, thickness is nearly O.3 mm) specimens, (Nb, Ti)N single phases were obtained at 1300°C 4h, and 1350°C within 48 h, respectively. In the nitriding of 50 V-50 Nb plate specimens (thickness is nearly 0.8 mm), needle-like nitride was not observed but a nitride layer with alloy composition developed from the surface into the inner part of specimen. (V, Nb)N single phases were obtained at 1350°C within 48 h.

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By using γ-manganese (N) oxide (MnO₂) electrode as an indicator electrode, the electrodereaction of ethylenediaminetetraacetic acid (EDTA) and several other complexanes has been investigated. The characteristic cathodic current peak of manganese (IV) oxide increases in the presence of complexanes. This is because the reduction of manganese (IV) oxide is accelerated through the complex formation. The heights of both the anodic and cathodic peaks are directly proportional to the complexane concentration. The electrode-reaction is extremely dependent on pH of the electrolysis solution; the characteristic cathodic peak cannot be observed at a pH higher than 2.5. The specific height of cathodic peak increases in the order of IDA<NTA<EDTA<DTPA.

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Hexaethylbenzene [6] and its related compounds have been nitrated under a, variety of conditions and the products characterized. When treated with nitric acid alone at room temperature, [6] gave 2, 3, 4, 5, r6, 6-hexaethyl-2, 4-cyclohexadienone[7] as a major product, while the reaction with mixed acid afforded 3, 6-dinitro-1, 2, 4, 5-tetraethylbenzene [14] along with a complicated mixture of unidentified carbonyl, nitro, and nitrooxy compounds. Pentaethylacetophenone [15] and pentaethylstyrene [9], were also converted to [14] via the loss of the acetyl and vinyl groups, respectively. However, 2, 3, 4, 5, 6-pentaethyl-α-methylbenzyl nitrate [8] failed to undergo a direct displacement of the α-nitrooxyethyl group with a nitro group under the conditions employed. By treatment with excess of mixed acid, 4, α-dimethylbenzyl nitrate [17] produced 4, α-dimethy1-3, 5-dinitrobenzyl nitrate [18] and 4-methyl-3, α, β-trinitrostyrene [19]. From 2, 4, 6, α-tetramethylbenzyl nitrate [20], an intimate mixture of the expected 3-nitro- and 3, 5-dinitro derivatives [21] and: [22] and an unidentified side-chain, nitrooxylation product was obtained. On the basis of the products isolated, a possible reaction pathway by which [6] can be converted to [14] has been suggested.

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The reductive coupling of iodo-p-xylene (IPX) by the use of palladium catalysts was carried out in the system consisting of reducing agent, solvent, base, and catalyst, etc. The optimum conditions for each parameter were examined.2, 2', 5, 5'-Tetramethylbiphenyl (TMB) was obtained in 74% yield under the optimum conditions with hydrazine hydrate, methanol, sodium h ydroxide, palladium chloride, and mercury (II) chloride (Fig.5). Both palladium chloride and mercury (II) chloride were reduced to the metals by hydrazine at the initial reaction stag e. The produced amalgam existed throughout the reaction and was quantitatively recovered after the reaction. In the cross-coupling of iodobenzene and iodomesitylene, biphenyl and 2, 4, 6-trimethylbiphenyl were obtained, while 2, 2', 4, 4', 6, 6'-hexamethylbiphenyl was not formed at all (Fig.7). The yield of biphenyls was decreased by the use of phenylhydrazine in place of hydrazine. These results were explained by the mechanism of dimerization through the reaction of an aryl palladium complex with iodoarene, which was different from the reaction mechanism reported by the previous investigators. The total reaction scheme, shown in Fig.1, was newly proposed.

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A high yield (95%) of p-aminobenzaldehyde was obtained when p-nitrotoluene was allowed to react with sodium polysulfide in the presence of N, N-dimethylformamide. The product was isolated in 90% yield as the chlorobenzene solution of p-aminobenzaldehyde when extracted from the reaction mixture. Alternatively, p-aminobenzaldehyde was obtained as sulfate (yield 90%) when the residue obtained by steam distillation of the reaction mixture was allowed to decompose with sulfuric acid.

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The reaction of dibenzofuran derivatives [1] with lithium (in a molar ratio of 1: 3) in boiling dioxane gave 2-hydroxybiphenyl derivatives in high yields. In the reactions of unsymmetrically methyl-substituted dibenzofurans, the bond between the unsubstituted ring and the oxygen of [1] was selectively cleaved to give methyl-substituted 2-phenyl phenols. On the contrary, in the reactions of phenyl-substituted dibenzofurans, the C-O linkage with the substituted ring was cleaved to give 2-(phenyl-substituted phenyl) phenols. The reaction of benzo [b]naphtho[2, 3-d]furan with lithium gave 2-(2-naphthyl)phenol in excellent yield. The regioselectivity of the cleavage reaction is discussed in terms of the differ ence in electron affinity between the two aromatic rings in [1].

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The effect of alkali halides on the catalytic activity of copper (II) acetate for the decomposition of α, α-dimethylbenzyl hydroperoxide in acetic acid has been examined. The activity of dimeric copper (II) acetate in the absence of alkali halide was poor. α, α-Dimethylbenzyl hydroperoxide decomposed rapidly as a result of the formation of copper (II) chloro complexes. The decomposition was accelerated with the increasing [LiC1]/2[Cu₂(0Ac)₄] ratio. Acetophenone was found to be a main product in the decomposition of α, α-dimethylbenzyl hydroperoxide by use of copper (II) chloro complexes. The reaction mechanisms which could explain the experimental results are discussed.

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Reverse osmosis separation of a single component aqueous solution of L-glutamic acid was carried out in a batch cell (200c m3) using the DDS-cellulose acetate membrane under the operating pressure of 1.96 MPa⋅G at 303K. High pH of the resulting solution (16 cm3 of initial permeate) as compared to that of the feed solution was noted (Fig.1). The phen omenon suggests that the cation (hydrogen ion) produced by dissociation of the mono amino dicarboxylic acid which is a zwitter ion is also adsorbed by the membrane. Also rejection increased as the concentration of the feed solution decreased. This behavior was consi dered to be due to the enlargement of electrostatic repulsion caused by increase of the proportion of ionic species R by increase of pH of the feed solution (Figs.2, 3 ). A model for the adsorptio n of the hydrogen ion was proposed (Fig.4). Equations for the hydrogen ion con centration adsorbed ([H⁺]a) and for the amount adsorbed (M) were theoretically derived, B y integration of [H⁺]a, between the limits zero and Ve (V where [H⁺]ais zero), the equilibriu m amount a' dsorbed (Me) was calculated (Figs.5-8). Adsorption isotherm of the hydrogen ion w as a pproximately represented by the Langmuir formula for each amino acid (Fig.9). When the amount adsorbed approached the equilibrium amount adsorbed rapidly, electrostatic repulsi on between monoamino dicarboxylic acid and dissociated groups of the membrane was w eakened with neutralization of the membrane caused by adsorption of the hydrogen ion. Rejection decreased as a result and approached constant value as permeation proceeded (Figs.10, 11). When the amount adsorbed approached the equilibrium amount adsorbed slowly, rejection wa s almost constant since charge density of the membrane was not varied so much with adsorpt ion of the hydrogen ion (Figs.12, 13).

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The separation of a solvent mixture of benzene and cyclohexane was investigated by the pervaporation technique. Membranes were synthesized by a crosslinking reaction of copolymer of 2-hydroxy-3-(diethylamino) propyl methacrylatestyrene with cyanuric chloride. The permeation mechanism was studied with respect to the chemical structure of the membrane. The desorption experiment was carried out on the solvent swollen membranes. The benzene composition in the membranes was found to be in agreement with that in the permeates. This result indicates that separation occured mainly in the process of dissolution of the solvents to the membranes, suggesting that selectivity and diffusivity can be controlled independently.
The permeation rate increased with the benzene composition in the feed. With regard to AA (O.7 )-StCC 5, the bending point was observed at the composition of about 50 wt%. It was found that a completely selective permeation of benzene was accomplished below the benzene composition at the bending point. On the other hand, plasticizing action took place in the membranes above the benzene composition at the bending point, resulting in the permeation of cyclohexane. It was observed that the bending point moved with the copolymer composition and the degree of crosslinking in the membranes. These results indicate that the perfectly selective membranes can be designed for any composition of feed solvents.

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A new type of a charged membrane has been prepared from the 4-vinylpyridinestyrene copolymer and performance of the membrane was examined. The preparation of the weak-basic type membrane was carried out in the N, N-dimethylformamidedioxane solvent medium. The membrane performance was very poor as a reverse osmosis membrane. The strong-basic type membranes were prepared by the reaction of the 4-vinylpyridinestyrene copolymer with I ( CH₂)nI (n = 4, 6) in N, N-dimethylformamide. The reaction was conducted to introd uce quarternary groups and intermolecular closslinking into membrane. These membranes have water flux of 2∼10l/m2⋅h and salt rejection of 90∼97% under 80 kg/cm2 with O.5% NaCl aqueous solution. These properties are closely related to the interstitial ionic concentration and water content of the membrane. The salt rejection (Rs), water permeability (k) and water content (H) were found to be expressed by equation, k=A⋅exp (BRs), k=ko⋅exp(-B'(1-H)/H).
The composite membrane was formed by casting the polymer solution in ultra-thin film on a polypropylene micro-porous supporter and by subsequent solvent evaporation at 65°C for 30min. Ethyl methyl ketoneN, N-dimethylacetamide (2/1, wt/wt) was found to be a prope r solvent for quarternarization of the copolymer and film casting. The membrane prepared from the 4-vinylpyridinestyrene (1/1, mole ratio) copolymer quaternized with 2 moles equivalent of the iodide had a good performance as a reverse osmosis membrane: water flux of 13.4l/m2⋅h and salt rejection of 97%.

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Inter-polymer anionic reverse osmosis membranes were prepared from ethylene-vinyl alcohol copolymer (EVA) and poly (styrenesulfonic acid) (PSSA) The effects of composition of a casting solution, temperature, and time of heat treatment on the performance of the resulting membranes have been studied. A mixture of 1-propanol and water (71.7/28.3, wt%) was used as a casting solvent. Membranes were prepared by casting a homogeneous polymer solution on a horizontal glass plate and by evaporating the solvent at a proper temperature. EVA homogeneous membrane had very poor performance as a reverse osmosis membrane. The optimum composition of a casting solution was as follows: weight percentage of EVA/PSSA/solvent being 9/6/85. The membrane was formed by casting the solution and heating at 120°C for 45min to give a good performance for reverse osmosis, viz., water flux of 4.5∼7.2l/m2⋅h an d salt rejection of 90∼91% under 80 kg/cm2 with 0.5% NaCl aqueous solution. The water flux and salt rejection closely related to interstitial ionic concentration and water content in a membrane.

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Decomposition reactions of nitrite (NO₂^-) in the rain water sampled in Kobe area were investigated. The concentration of NO₂^- and pH of the samples were adjusted at [NO₂^-]₀=0.03∼3 ppm (containing both NO₂^- and HNO₂) by adding NaNO₂ and at pH=7∼2 by addin g H₂SO₄ or NaOH to the rain water. The NO₂^--decomposition rates were increased with a decrease in pH value and with an increase in temperature at pH=5∼2 (Figs 2∼6, 10), and were influenced by the other ions in the rain water (Fig.9) and by the gas-liquid interface of the sample water (Fig.8). More than one-third of the total amount of NO₂^--N decomposed was oxidized to N08--N (Fig.11).
These results indicate that NO₂^- in the rain water is decomposed by the disproportionation reaction shown as 2HNO₂=NO+NO₂+H₂O (3 HNO₂= HNO₃+2NO+H₂O) and that some amount of the NO, reducted product, is further oxidized to NO₃^-, and support the previous field study that the NO₃^--N/NO₂^--N ratio in the rain water sampled in urban areas increased with a decrease in pH¹.

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The rain water was collected by sequential sampling of 50 ml per every 0.5 mm rainfall in Kobe area during the period from July, 1976 to March, 1977, and the concentrations of dissolved ions, pH and electric conductivity in the water were determined and compared with those of atmospheric pollutants in the same area. The H⁺ concentration and H⁺/(H⁺+Na⁺+NH₄⁺) mol%, werp higher in summer than that in winter (especially in the initia l rainfall, 2.5mm>, Table 1, Fig.5). The H⁺ concentration changed depending mainly on NO₃^-, and also increased with an increase in the electric conductivity in summer and autumn (Fig.4). Whereas the Cl^-/Na⁺ molar ratio in the rain water was nearly equal to the composition of sea water, the ratio in particulate mater in the air was lower than that of sea water (especially in summer) by the reaction of NO₂-H₂O with NaCl (Figs.2, 3). The concentrations of NH₄⁺-SO₄^-2 and Na⁺-Cl^- in the rain water decreased gradually with an increase of the rainfall amount, and the decrease was more remarkable for Na⁺-Cl^- (Fig.1).
The molar concentrations of the anions in the rain water were fou nd in the order of SO₄^2->Cl->NO₃^- in the period from summer to winter, and those of the cations were found in the order of H⁺>NH₄⁺≈Na⁺ in summer and autumn, and Na⁺>H⁺≥NH₄⁺ in winter (Fig.5).

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By using γ-mangane(N) oxide (MnO₂) electrode as an indicator electrode, the oxidation of ethanol was investigated. A characteristic anodic peak was observed in the cathodic sweeping, and the peak height increased with increasing concentration of ethanol. As the pH of solution increased, the anodic peak potential shifted towards a more negative side (about 600 mV) at. pH 11. A similar behavior of ethanol was also observed with a platinum electrode.

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Liquid-liquid distributions of five alkali ions between solvents such as nitromethane, nitrobenzene, 4-methyl-2-pentanone, or 4-methyl-2-pentanol and aqueous sodium perchlorate solutions were studied at 25°C. The distribution ratio (D) was higher in the increasing order of the ionic size of the alkali metal ions for the nitromethane and nitrobenzene. However, the values of D of these metal ions were rather similar when the solvent was 4-methyl-2pentanone and 4-methyl-2-pentanol. The distribution ratio was found to be reduced by the co-extraction of sodium, perchlorate.

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A new class of 6, 13-bis (arylamino) triphenodithiazines have been prepared by a novel synthetic procedure and their several properties were determined. The preparative method consisted of the following two steps. ( a ) The condensation of chloranil with an arylamine in a molar ratio of 1: 2 in ethanol gave 3, 6-bis (arylamino) -2, 5-dichloro-1, 4-benzoquinone [3] in high yield. ( b ) The reaction of [3] with the zinc salt of 2-aminobenzenethiol in Cellosolve containing C₂H₅ONa gave eight derivatives of title compounds [6].
The structures of [6] were confirmed on the basis of the elemental analysis, infrared spectra and mass spectral data. The streak color of the eight compounds was deep violet and the absorption maxima of their visible spectra in dioxane were found to be in the narrow visible region from 556 to 560 nm. Their decomposition temperature examined by DTA were as high as 428∼500°C.

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