Redox reaction of 2, 3: 5, 6-dibenzo-1, 3 a, 4, 6 a-tetraazapentalene (1) and 2, 3: 4, 5dibenzo-1, 3 a, 6, 6 a-tertaazapentalene (2) has been investigated by using ESR techniques. On the alkali metal-reduction of both compounds, the ESR spectrum of the phenazine anion radical (C^4-.) was finally observed after the appearance of a structureless broad signal (Fig.2and Scheme 1). The ESR spectra for the cation radicals of (1) and (2) were measured (Tables 1 and 2). The hyperfine splitting constants (hfsc) derived from their analyese are nicely supported by molecular orbital (MO) calculation of these molecules. The electronic states of (1) and (2) are compared with those of indeno[2, 1-a]indene (3).

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Copper indium diselenide, CuInSe₂, is one of the most promising materials for photoelectrochemical application because of the excellent output stability and high efficiency of energy conversion of the cell using its single crystal photoelectrode. In this work, an attempt has been made to obtain CuInSe₂ films by a simple electrodeposition technique with an emphasis on the effects of additives in the plating bath on the morphology and some properties of deposits. Smooth CuInSe₂ films with good adherence to the substrate have been obtained by electrodeposition on Ti plates from a simple sulfate bath containing CuSO₄, In₂(SO₄)₃, H₂SeO₃ and small amount of gelatin as an additive under a careful con trol of deposition potential.
The occur rence of co-deposition of the three elements of which deposition potential varies greatly with each other, is based on the underpotential deposition of In on a substrate covered with Se and Cu species. A comparison of SEM photographs displayed in Fig.9 ( a ) and ( b ) clearly shows that gelatin in the plating bath contributes to the deposition of CuInS e2films with very homogeneous thickness. EPMA data (Fig.3) and X-ray diffractometric analysis (Fig.11) indicate that these films annealed at 600°C in nitrogen atmosphere have a chalcopyrite structure with nearly stoichiometric composition. Most of these films have exhibited the p-type photoresponse in a photoelectrochemical system. The band gap has been estimated to be 0.98 eV for the direct transition by extrapolation of the linear (I_ph×hν)² versus photon energy plots shown in Fig.14.

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Adsorptive activities of various, stable and nontoxic metal oxides for phosphate ion were examined in order to find an effective adsorbent for the removal of excess phosphate ions in the human blood. The adsorption experiments were mainly carried out in a diluted aqueous solution of NaH₂PO₄.
The adsorptive acti vities of metal oxides appered to be dependent on the surface basicities of the oxides. Thus, MgO showed the highest activity among the oxides tested in this experiment. The adsorptive activity of MgO was further enhanced by an addition of a small amount of Ti02. The amount of phosphate ions adsorbed on the TiO₂ doped MgO roughly corresponded to the amount of surface OH groups detrmined by the exchange with F^- ion (Fig.5). Langmuir equation was applicable to this adsorption (Fig.6), and saturated amount of adsorption on the TiO₂ doped MgO (Ti/Mg atomic ratio=1/99) at around room temperature was calculated to be about 10 mmol of phosphate ion per 1 g of the mixed oxide. The amount of adsorbed phosphate ion was not affected by the presences of various metal ions.

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Effects of pressure upon the rate of mutarotation of α-D-glucose to β-D-glucose in dimethyl sulfoxide over an alumina catalyst have been studied at a constant temperature of 40±0.1°C under various pressures in the range of 0.1-90 MPa. The initial α-D-glucose concentration was varied in the range of 2.8-12×10^-2 mol/dm³.
It was concluded that the same surface reaction proce eds in the pressure range examined, though an increase of the pressure retarded the reaction rate. Thus the kinetic parameters Kα(α-D-glucose adsorption coefficient), Kβ(β-D-glucose adsorption coefficient), k1 (the rate constant for the surface forward reaction), and k2 (the rate constant for the surface backward reaction) were evaluated as a function of pressure.
The pressure dependences of both Kα, and Kβ were very small (the volume changes ΔVα=ΔVβ=0 cm³/mol), suggesting that the desolvation from anionic adsorption sites compen sates a negative volume change on adsorption. On the other hand, fairly large positive activation volumes were obtained; V1≠=22±4 cm³/mol (surface forward reaction) and V2≠=20+3 cm³/mol (surface backward reaction). This is in sharp contrast to the negative activation volume for the homogeneous catalysis and suggests that the transition state of the heterogeneous reaction is quite different from that of the homogeneous reaction. A simple model calculation has shown that a formyl group rotation step which requires a vacant hole of 22 cm³/mol is mainly responsible for the most of the observed positive activation volume.

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HexOltioreacetone (HFA) was readily formed by circulating a gaseous mixture of hexafluoropropene (HFP) and. oxygen over platinum group metals supported on carbon. Only CO₂ was detecteli as the by-product after the HFP oxidation. Both epoxidation of HFP to hexafluoro; propylene oxide (HFPO) and isomerization of HFPO to HFA were not observed over Pd/C catalyst. Thus, it could be possible that HFA was formed directly by the oxidation of HFP.
An induction period was observed in this oxidation, while it was not observed for the reaction carried out over the used catalyst.
XPS, study for the supported Pd catalyst suggested that the surface of metallic Pd particles acted as the active sites for the HFA formation.

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Zirconium-montmorillonite clays prepared by intercalation in ZrOCl₂ aqueous solution were investigated by Extended X-ray Absorption Fine Structure (EXAFS) with synchrotron radiation. X-ray absorption of Zr K-edge was measured for two Zr-montmorillonites with diffreent amounts of exchanged Zr cations, ZrOCl₂ aqueous solution and Zr0₂. Radial distribution obtained from Fourier transformation of EXAFS spectra showed two peaks due t o the Zr-O and Zr-Zr bonds at about 2.1Å and 3.5Å, respectively. The intensities of peaks due to Zr-Zr and Zr-O bonds suggested that the polymerization of Zr cation with degree of four and two occurred in the interlayer of the clays. MEM (Maximum Enthropy Method) spectra showed the presence of fine structures of Zr-O bonds which could be attributed to the mixture of Zr-OH and Zr-OH₂ bonds. The longer Zr-O bonds were found to disappear by the heat treatment at 500°C, indicating the formation of pillars of zirconium oxide in the interlayer of montmorillonite.

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A method for preparing crystalline titanium (IV) bis(hydrogenphosphate) dihydrate, Ti(HPO₄)⋅2H₂0(γ-TiP), was established by the reaction' of titanium(IV) hydroxide, TiO₂⋅nH₂0, or titanium oxide, TiO₂ (rutile and anatase type), with orthophosphoric acid in an autoclave.
In the titanium(IV) hydroxide and titanium(IV) oxide systems, the preparation of γ-TiP was significantly affected by mixing ratio (P₂0₅/Ti0₂), heating temperature, heating time, and water vapor pressure in the autoclave. The recommended method for the preparation of γ-TIP can be summarized as follows; in the titanium (IV) hydroxide system, the mixing ratio of P₂0₅/Ti0₂ is 1.2-1.5, the heating temperature is 225-250°C, heating time 3 h, and water vapor pressure over 15 a tm, and in the titanium(N) oxide system the mixing ratio is 1.5, heating temperature 200-210°C, heating time 3 h, and water vapor pressure over 8 a tm. γ-TiP prepared by the present method effectively adsorbed ammonia in an aqueous solution and ammonia gas.

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The kinetics of aniline elimination reactions of [Ni(acac)₂B₂] complexes {Hacac=acetylacetone and B=aniline or its derivatives} have been studied in the solid state by the Coats Redfern method on the basis of the weight loss curves recorded at a heating rate of 1°C/min in nitrogen stream, 100 ml/min, :
[Ni(acac)₂B₂]_??_Ni(acac)₂B +B↑_??_Ni(acac)₂ +B↑
The values of the rate constant and the activation energy were determined from the slopes of the plots of log[-log(1-α)/(2.303. T²)] vs 1/T. Then, the activation free energies (ΔG) were calculated from the values of the activation energy and the frequency factor. The ΔG/values for the first and the second elimination reactions, ΔG(383K) and ΔG(435K), varied in the range of 109-127kJ.⋅mol^-1 and 130-439 kJ⋅mol^-1, respectively, depending on the nature of aniline derivatives. A linear correlation was observed between the ΔG values and pKa values of aniline derivative except for the complexes with p-chloroaniline and p-bromoaniline. These complexes with p-chloroaniline and p-bromoaniline were more stable (ca.26 kJ⋅mol^-1) than expected from their pKa, values. These results suggested that the kinetic stability of [Ni(acac)₂B₂] complexes mainly depends on the pKa and the heat of sublimation of aniline derivatives.

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Radiation pretreatment of cellulosic wastes such as saw dust and chaff was studied by using electron beam accelerator, in which irradiation effect was increased by increasing irradiation dose and dose rate, by after heating irradiated materials at 100-140°C, and by irradiation in the addition of alkaline solution. Trichoderma reesci cells producing cellulase were immobilized by using fibrous porous carrier obtained from radiation polymerization. The filter paper, cellobiose, and CMC activities in the immobilized growing cells were higher than those in free cells. The activity in the immobilized cells obtained with hydrophobic carrier was higher than that obtained with hydrophilic one. Durabiltty of the immobilized cells was examined by repeated batch culture. It was found that the enzyme solution produced in the culture of the immobilized cells can hydrolyze effectively saw dust pretreated by radiation.

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Production conditions of fructooligosaccharides(I) from sucrose catalyzed by immobilized p-fructofuranosidase(II) were investigated. β-Fructofuranosidase(II) was obta ined from Aspergillus oryzae and DEAE-cellulose was found to be the best among several carr iers tested. The optimal temperature and pH for production of I were 40°C and 7.8, respectively. Glucose formed from sucrose decreased the fructosyl-transferring activity in the same manner as the case of the enzyme from Aspergillus niger. To utilize sucrose effectively, glucose was converted to fructose by glucoseisomerase at the time when the hydrolyzing activity overcame the transferring activity and then the transferring reaction was carried on using II. It was concluded that this two step process was useful for the production of I from sucrose under restriction of the hydrolyzing activity.

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5, 10, 15, 20-Tetrakis(α, α, α, α-o-pivalarnidophenyl)porphyrinatoiron(II) derivatives bearing a side chain with a terminal imidazolyl group were synthesized. A formyl group was introduced. at the 2-position of the corresponding porphyrinatocopper(II) using Vilsmeier-Haack reaction. The resultant 2-formylporphyrinatocopper(II) was demetallated with sulfuric acid. Treatment of this with sodium borohydride gave the 2-(hydroxymethyl)porphyrin in a quantitative yield. Reaction of this successively, methanesulfonyl chloride, sodium azide, and triphenylphosphine yielded the 2-(aminomethyl)porphyrin. Condensation of the 2-formy lporphyrin with malonic acid in the presence of piperidine (Knoevenagel reaction) selectively afforded the 2-(trans-2-carboxyeth'enyl)porphyrin. Using these functionalized porphyrins, 5, 10, 15, 20-tetrakis(α, α, α, α-o-pivalamidophenyl)porphyrinatoiron(II) derivatives bearing a terminal imidazolyl group were prepared.

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2-[trans-2[[L-[2-Hexadecylcarbamoyl-1-[[3-2-(methyl-1-imidazolyl)propyl]carbamoyl]]ethyl]carbamoyl]ethenyl]-5, 10, 15, 20-tetrakis(α, α, α, α-o-pivalamidophenyl)porphyrinatoiron(II) was efficiently solubilized in physiological solutions with surfactants, such as a poly(oxyethylene)derivative, and L-a-dimyristoylphosphatidylcholine. The resultant micelle or liposomeembedded lipophilic porphyrinatoiron binds molecular oxygen reversibly under physiological conditions (pH 7.0 aqueous medium, 37°C). The oxygen- and carbon monoxide-binding rate constants and affinities were similar to those of red blood cell.

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Hydroxymethylation of melamine with formaldehyde was kinetically investigated in aqueous acetate buffer solution ([CCH₃COOH]/ECH₃C00^-1=1.0), and Arrhenius plot was established, to estimate activation parameters. In addition, the equilibrium constants and the changes of the enthalpies were evaluated for the conjugate acid formation by the reaction of melamine with H⁺, N-(hydroxymethyl)melamine formation by the hydroxymethylation of melamine with formaldehyde without additional catalyst, the conjugate acid formation by the reaction of N-(hydroxymethyl)melamine with H⁺, and the acid dissociation of acetic acid.
By the use of these thermodynamic parameters together with the literature values of the equilibrium constant and the change of the enthalpy for hydroxymethyl cation formation by the reaction of formaldehyde with H⁺, the frequency factors of the forward and reverse reactions were evaluated, when the forward reactions of the respective elementary reactions on the acid-catalyzed reaction mechanisms reported previously, are assumed to be ratedetermining steps.
As a result, acid-catalyzed reaction mechanism based on the thermodynamic investigationin this paper was in agreement with the mechanism speculated from the slope of the Bronsted plot in the previous paper.

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Eight t-butyl esters of substituted perbenzoic acids having o-, p-methoxy, o-, m-, p-chloro, 0-, p-nitro and o-carboxyl groups were synthesized. Five o-, m-substituted derivatives of these perbenzoates have not been reported yet. The first-order decompostition rate constants (kd)were determined in chlorobenzene at 120°C and the substituent effects on kd were discussed together with those for the other t-butyl perbenzoates given in the literature.
The Hammett, plot for these four m-, p-substituents and p-methyl group gave a straight line, but a plot of p-methylthio group deviated from the line. However, all of the substi tuents was closely correlated with the modified Hammett equation considering the resonance effect, log(k/k0) = pσ+γER; ρ=-0.7 and γ=O.33 were obtained. This result shows that the decomposition rates of these perbenzoates are governed by, both the factors of polarity and resonance of the substituents.
The decompositio n rates of perbenzoate were increased by a o-methoxy or o-chloro group, but decreased by a o-carboxyl or a o-nitro group. A linear correlation was found between kd and o-substituent constant, ρ*. The substituent effects observed for o-substituents were found to be much smaller that those of o-phenylthio and o-methylthio groups which were reported by Martin et al. There were attributed to the effect through the benzene ring like p-substituents rather than neighbouring substituent participation proposed by Martin et al.

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New isopropenyl-1, 3, 5-triazines, e. g., 2-(amino or anilino)-4-(p-ethyl or butylanilino)-6isopropeny1-1, 3, 5-triazines [ 1]--[ 4] were prepared. The homopolymerization of these monomers and their copolymerization with styrene, methyl methacrylate and methyl acrylate (M1) were carried out using azobisisobutyronitrile as an initiator in dimethyl sulfoxide. The copolymerization parameters (r1, r2, Q 2 and e2) were determined fo r these monomers. The relationships between the glass transition temperatures and composition of the copolymers were investigated. Thermal polymerization of [1][4] was studied by differential scanning calorimetry (DSC). The ceiling temperature (Te) and the heat of polymerization (ΔHp) were obtained from DSC data. The effect of alkyl groups was observed in the thermodynamic parameters of polymerization.

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Network polymers which have highly ordered and densified crosslinkages are expected to be a new material with good mechanical properties.
In order to obtain these polymers, it has been studied on both preparation of 1, 6-bis (acryloylamino)-2, 4-hexadiyne as a monomer capable of forming a dense crosslinkage in the solid state and their molding method under hydrostatic pressure.
(1) The title diacetylene compound has two functio nal groups, that is, a diacetylene moiety and a carbon-carbon double bond. These unsaturated groups are highly reactive toward thermally induced solid state reaction. IR spectral observations and TGIDTA analyses show the two step reaction composed of the polymerization of the diacetylene moieties and the reaction of the acryloyl groups occurs in the solid state. Consequently this compound was observed to undergo crosslinking through the two step reaction, yielding a dense network polymer.
(2) The powder compression molding of the compound was investigated. The properties of moldings are highly dependent on the applied pressure and the molding temperature. These moldings have excellent properties isotropically, such as modulus, ultrasonic velosity, Vickers hardness, thermal conductivity. The maximum value of moduli reached 18 GPa. In this case the value of Vickers hardness (255) largely surpasses those of iron (138) or coppei (80). The thermal conductivities of the moldings are about two or three times larger than those of common polymers.

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This paper presents the results on application of hydrous zirconium (IV) oxide dynamic membrane layered on ceramic membrane(Zr-CM membrane) as a separation membrane in the membrane reactor, which produces 5′-inosinic acid (IMP) from ribonucleic acid (RNA). The consecutive enzymic reactions were carried out by using two enzymes(phosphodiesterase and AMP-deaminase). The membrane reactor was composed of a feed tank, a Zr-CM memberane filter and a feed pump. Low molecular compounds (IMP and mononucleotides)produced by enzymic reactions were separated from high-molecular compounds (RNA and enzymes) by Zr-CM membrane filter. It was expected that both enzymic reactions and filtration by Zr-CM membrane went on simultaneously and that a steady state was attained by adding requisite amounts of RNA, which corresponded to the amount of IMP and mononucleotides removed from the membrane reactor by filtration.
The membrane reactor, filled with 0.95 dm³ of 50 g/dm³ RNA containing 100 units of phosphodiesterase and 1000 units of AMP deaminase, was operated under gauge pressure of 2 kg/cm² and feed velocity of 1 m/s at 50°C for 166 h. Activities of two enzymes were kept constant by adding enzymes at intervals. Enzymic reactions and filtration reached a steady state after 70 h, the rate of RNA addition was balanced with that of mononucleotides filtration. Rejection of RNA, flux, concentration of IMP and conversion ratio from AMP to IMP were found to be constant at 0.95±0.02, O.03 m³/ (m²d), 21-22 dm³ and 0.95±0.02, respectively.

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The cross-linked polystyrene resin containing L-lysine-N^α, N^α, N^ε-triacetic acid moieties has been prepared by regioselective introduction of L-lysine onto polymer beads thro ugh its ε-amino group, followed by carboxymethylation of the amine moieties. The ligand grou p which is structurally close to nitrirotriacetic acid locates relatively remote from the pol ymer matrix by spacing with carbon chain. The equilibrium adsorption capacities, and distr ibution coefficients of the newly prepared resin have been studied for group Bib metal ions and other common metal ions. The maximum adsorption capacities for these metal ions are ca.1.2-1.5 mmol/g-resin which is close to the ligand content involved in the resin (1.54 m m ol/g-resin). The selectivity sequence of the resin for the representative metal ions is as follows: Ga(III)>In(III)>Cu(II)>Al(III)>Ni(II)>Zn(II)>Co(II)>Fe(II). The present resin can retain trivalent metal ions such as Al ( ffi ), Ga(M), and In= much mo re firmly than the conventional chelating resins having iminodiacetic acid moieties. The meta l ion solution (pH 1.8, 2 dm³) containing Ga(III) (2.1 mM) and Zn(II) (200 mM) has been pass ed through the column of the present resin (5 g), Ga(III) is quantitatively adsorbed (ca, 98 %) on the resin, while Zn( II) is found in the eluate. In a similar manner, the selective recover y of Ga(III) and/or In(III) from acidic solution containing large amount of Zn(II) or Al(III) has been demonstrated using a column of the present resin.

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Metal components composition of hopeite films formed on galvannealed steel and phosphophyllite films formed on cold rolled steel by the treatment in various zinc phosphate solutions shown in Table 1 are determined (Table 2), and the Laser Raman spectra for these films were observed. The influence of metal components composition on the peak position and profile of Raman spectra were investigated.
Raman spectra for these films were shown in Figs.1-5. Four clear peaks due to PO₄^3- were found in the region of 800-1300 cm^-1. Orthophosphate (PO₄^3-), which is regular tetrahedron, has four basic vibration modes of νi, ν2, ν3, and ν4, (Fig.6), ν1, and ν3 being observed in 800-1300 cm^-1. Essentially, ν3, degenerates triply. But in the crystalline state of zinc phosphate films, the symmetrical shape of regular tetrahedron of PO₄^3- will be deformed by the interaction, and the degeneracy of ν3 are untied and splitted to three peaks. Accordingly, it was considered that the spectra with four peaks containing ν1, were generated. Here, main peak corresponds to v, and other three peaks correspond to ν3.
The values of Raman peak for various zinc phosphate films were compared (Table 3). For both hopeite films and phosphophyllite films, Raman peak shifted to lower wavenumber with the increase of nickel or manganese (Fig.7). In particular, the Raman band of hopeite films formed in solution C and D was similar to that of phosphophyllite films formed in solution A.
Modified structure of hopeite films by the doping of nickel or manganese has been analyzed as Zn₃_xMex(PO₄)₂⋅4H₂0 (Me: Ni or Mn). This structure is different from neat hopeite films of Zn₃(PO₄)₂⋅4H₂0 and is modified to the structure as phosphophyllite films. Thus, it was possible to correlate the modification level of zinc phosphat e films by the observation of PO₄^3- peak shift in Raman spectra.

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The distribution of some trace elements (Sn, Cu, Pb, Zn, and Mn) in the bottom sediments at Maizuru Bay, Kyoto Prefecture and at Seto Harbor, Nagasaki Prefecture has been studied.
The concentrations of tin, copper, lead, zinc and manganese were determined by atomic absorption spectrophotometry (AAS) after wet ashing with a mixture of hydrochloric and nitric acids (3: 1). The analytical results are given together with coefficients of correlatio n between some trace elements. The concentrations of copper, zinc, lead and man ganese at MaizuruB ay weres ignificantlhyi ghert han thoseat Seto Harbor, whilet he concentration of tin was almost the same in each Bay. According to the distribution of some trace elements, it is found that copper, zinc and lead in the bottom sediment at the Bays show a similar behavior, although manganese and tin show different behaviors.

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The line width of each hfs line in ESR spectrum of a cation of N, N, N′, N′-Tetramethylpphenylenediamine (TMPD^.+) formed in a mixture with butyl titanate polymer varies with the nuclear spin quantum number. Simulation of the ESR spectrum of TMPD^.+ has been made using the line width which varies with nuclear spin quantum number. The contribution of τc(A-B) m₁/h² term to the line width was investigated to see which of the m_Ivalues, m_I of benzene ring protons, m_I, of methyl protons, or m, of nitrogen nuclei, is contributing most.
The result indicates that the line width originating from the protons of the benzene ring is nearly 10 times as large as those coming from the protons of the methyl groups and the nitrogen nuclei. Therefore TMPID^.+ in the butyl titanate polymer is considered to be fixed at the phenyl ring.

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Several λ-MnO₂ specimens were prepared by HCl-treatment of LiMn₂0₄ synthesized by heating the mixtures of Li₂CO₃ and MnCO₃ (Li/Mn molar ratio 0.05-0.5) at 600-1000°C for 8 h.
The effect of synthetic conditions of LiMn₂0₄ on the lithium adsorbability has been studied. The λ-MnO₂ specimen which shows high Li adsorbability could be formed from products with Li/Mn =0.1-0.25 at 800-1000°C (Fig.1).
The λ-Mn0₂ under the above synthet ic conditions collected lithium selectively from geothermal brines at 100°C (Table 1).

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Effects of the conditions of hydrofnermal decomposition (temperature, time, alkaline concentration, degree of filling and addition of Na₂Si0₃) on the formation of carbon from chlorinated organic materials were studied by using a microautoclave.
The carbon formed by dechlorinating decomposi tions of 1, 1, 1 -trichloroethane had spherical particles with uniform diameters (3-5 νm). Silicate ion had a large effect on carbonation of 1, 1, 1-trichloroethane under the alkaline hydrothermal conditions of 300°C, 300 kg/cm², 24reaction time. It was easy to form graphite structures. However, polychlorinated adamantanes did not transform to graphite tructure but only to the amorphous one with addition of Na₂SiO₃.
It was suggested that the silicate acts as a catalyzer of graphitization from organic materials and the graphite among silicate rocks may be formed at relatively mild conditions around the critical point.

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N-Alkylation of phenanthro [9, 10-d] triazole [1a] gave the mixture of 1- and 2-alkyl derivatives, the latter being predominant. The ratio of these isomers was in contrast to the N-methylation of benzotriazole [3a]. N-Phenylation of [1a] gave the 2-phenyl derivativ e [2f] exclusively. The 2-position of [1a] was alkylated in preference to the 1-position, contrary to the previous paper.

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