A new method of forming O/W emulsion having fine and uniform droplets has been developed. This method consist of two steps. The first step is to make O/D gel emulsion by adding oil to a surfactant phase containing water and diols. The second process is to make O/W emulsion by adding water phase to the O/D emulsion. The factors for forming O/D gel emulsion was investigated from the phase diagrams of water?liquid paraffin-1, 3-butanediol-surfactant systems and the interfacial tensions between surfactant and oil phases. It has been elucidated that the composition of surfactant-1, 3-butanediol-water is important in making O/D gel emulsion, and that the role of diol is to prevent D phase forming liquid crystals. The range of HLB-number where the fine O/W emulsion forms is broadened by using the D phase emulsification method.

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The rates of air oxidation of iron(II) in solution were measured in the presence of copper (II) and/or iron(III) oxidehydrate at a fixed pH. The rate equation obtained for solutions containing iron(III) oxide hydrate but not copper(II) was :
-d[Fe(II)]/dt=k₁[Fe(II)]·P_O2 (1)
where[Fe(II)] denotes the total concentration of all the iron(II) species in the system. The equation obtained for solutions containing copper(II) but not iron(III) oxide hydrate was :
-d[Fe(II)]/dt=k₂[Fe(II)]²·P_O2 (2)
The rate constants k₁, and k₂ were found to increase with the concentraions of iron(III) oxide hydrate and copper (II), respectively, and hence they catalyse the reaction.
Provided that the rate of oxidation in the presence of both copper(II) and iron(III) oxide hydrate is expressed as the sum of the rates of (1) and (2), the following equation is obtained :
1/k₁ln([Fe(II)]₀(k₁+k₂[Fe(II)]))/([Fe(II)](k₁+k₂[Fe(II)]₀))=P_O2·t (3)
where [Fe(II)]₀ is the initial value of [Fe(II)]. With the values of k₁, k₂, P_O2 and [Fe(II)]₀, the theoretical [Fe(II)] vs. time relationship was calculated from eq. (3), and it agreed well with the experimental results.
The catalytic action of iron(III) oxide hydrate and copper(II) was explained in the following way. For iron(III) oxide hydrate a small portion of iron(II) is adsorbed, and the oxidation proceeds via the adsorbed species. In the presence of copper(II) a small amount of copper(I) is formed by the redox reaction between iron(II) and copper(II), and thiis copper(I) initiates the reaction between iron(II) and oxygen.
The proposed mechanism gave quantitative explanation of the dependence of the oxidation rates on the concentrations of iron(II), iron(III) oxide hydrate and copper(II), and the partial pressure of oxygen.

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It was attempted to group the reaction system on the basis of the isokinetic temperature(β) for the deacylation of variuos phenyl esters catalyzed by L-histidine derivatives and hydroxamic acids. The correlations between the β value and the average of experimental temperature (T) for the distinct reaction systems were as follows: (a)β>T for the micellar system, ( b ) β<T for the bilayer system, (c) β>>T for the macromolecular system. Furthermore, it was suggested that the indistinct reaction system would be grouped by the β value in connection with the T value.

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The electrode reaction mechanisms and the chemical equilibria of bis(β-diketonato)nickel(II) complexes in dimethyl sulfoxide were studied by means of conductivity measurements, cryoscopy, polarography (dc, diff. pulse, and oscillograph), and cyclic voltammetry. The complexes of [Ni(dbm)₂], [Ni(bfac)₂], [Ni(ftac)₂], and [Ni(ttac)₂] were used : dbm^-, bfac^-, ftac^-, and ttac^- denote the enolate anions of dibenzoylmethane, benzoyltrifluoroacetone, 2-furoyltrifluoroacetone, and 2-thenoyltrifluoroacetone, respectively. In 0.05 mol·dm^-3 TBAP solutions, the main conclusions are summarized by the scheme(I) for [Ni(dbm)₂] and by the scheme(II) for the other complexes.
Ni(uni-dbm)⁺←slow→Ni(bi-dbm)⁺←k₂₃, k₃₂→
2e↓1st wave 2e↓2nd wave
Ni(bi-dbm)(uni-dbm)←slow→Ni(bi-dbm)₂
2e↓3rd wave 2e↓4th wave (I)
Ni(uni-L)⁺←slow→Ni(bi-L)⁺←slow→
2e↓1st wave 2e↓2nd wave
Ni(bi-L)(uni-L)←slow→Ni(bi-L)₂
2e↓3rd wave 2e↓4th wave (II)
In the above schemes, unidentate and bidentate are abbreviated as uni- and bi-, respectively.

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This paper reports the results of the newly developed reanodizing method applying to the electrolytic colored films on aluminum. The purposes of the reanodizing method were to give various functions and more durability against the colored films. Porous anodic oxide films were formed in aqueous solution of sulfuric acid or phosphoric acid, and then coloring and reanodizing were performed on the films. As the results, the colors of the films, colorized by the deposition of nickel or tin, became lighter. The color of the films by the nickel deposition changed to colorless state which is generally obtained by the anodizing, while the color by tin slightly changed. The colors of these films were controlled by the reanodizing voltage and/or the electrolytic duration. Furthermore, variations of the microstructures in cross-section of the colored films were observed before and after reanodizing by a transmission electron microscope. From the observation by the transmission electron microscope and current density-reanodizing time curves, the following presumption was made : In the case of the nickel deposition, leaving of the nickel deposits from the pores by reanodizing causes the color change, while in the case of the tin deposition, the tin deposits in the pores were passivated by reanodizing and bring slight color change. Especially, the leaving of the nickel deposits from the pores seemed to depend on the presence of ultra fine particles in the deposits and on the uneven thickness of the anodized barrier layer. On the other hand, the durabilities of these colored films were found to be improved considerably by increasing the thickness of the barrier layer or by formation of the chemically stable passive state layer.

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When a Fe₃O₄ film deposited on a stainless steel was soaked in a Fe(OH)₂ suspension bubbled with air, Fe₃O₄ grew on the film. Its surface reaction was investigated. When iron(II) ions adsorbed on the film were oxidized, a γ-FeOOH-like layer was formed and transformed to Fe₃O₄ through further adsorption of iron(II) ion. A γ-FeOOH film deposited on a stainless steel by anodic oxidation was transformed to a Fe₃O₄ film through adsorption of iron(II) ion. Moreover, it was found that the surface of the Fe₃O₄ formed in the course of the air oxidation was composed of a γ-FeOOH-like layer and the iron(II) ion adsorbed on the layer. A surface reaction mechanism that the γ-FeOOH-like layer is formed on the surface by oxidation of the adsorbed iron(II) ion and transformed to the new Fe₃O₄ layer is speculated on the basis of the above results. A ferrite formation mechanism in solution was also discussed.

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The kinetics of the complexation reaction of scandium(III) with Arsenazo III has been studied by a stopped-flow spectrophotometric method in the pH range 0.5-0.9 at μ=0.5 (Na-ClO₄) and 25°C. The reaction was of first-order with respect to the concentrations of scandium(III) and Arsenazo III and of inverse first-order with respect to the hydrogen ion concentration. The rate-determining step in the complexation reaction was found to be the 1 : 1 complex forming reaction between scandium(III) and Arsenazo III (H₅R^3-). The rate constant at μ=0.5 and at 25°C was calculated as 2.21×10⁴ dm³·mol^-1·s^-1. The activation parameters are as follows : Ea=48.5kJ·mol^-1, ΔH^≠=46.0kJ·mol^-1, ΔS^≠=-7.28J·K^-1·mol^-1 and ΔG^≠=48.1kJ·mol^-1. The water-exchange rate constant for scandium(III) ion was evaluated to be 2×10²s^-1 on the assumption that the complexation reaction obeys the Eigen mechanism. In connection with the kinetic study the acid formation constants of Arsenazo III have been determined spectrophotometrically at μ=0.2 and at 25°C : logK^H_H6R=1.80, logK^H_H5R=3.31, logK^H_H4R=6.65, logK^H_H3R=8.86, logK^H_H2R=11.10 and logK^H_HR=-14.92. These values are in approximate agreement with the latest ones reported by Budesinsky. A method for the purification of Arsenazo III is also described.

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Kinetics and mechanism of the complexation reaction of uranium (VI) with Arsenazo III have been studied in the pH range 0.3-2.0 by using a stopped-flow spectrophotometric method. The reaction scheme can be expressed as follows :
where H₆R^2- and H₅R^3- refer to bivalent and tervalent anions of Arsenazo III, respectively, K^H_H6R is the acid formation equilibrium constant of H₆R^2- and P is the reaction product. Rate constants, k₁ and k₂, are kinetically determined at 25°C and μ=0.5 : k₁=2.07×10⁵dm³·mol^-1·s^-1 and k₂=1.25×10⁶dm³·mol^-1·s^-1. If these reactions follow the Eigen mechanism, the ratio of the experimentally obtained rate constants, k₂/k₁ (=6.0), can be discussed in terms of the difference of the outer-sphere association constants [K_{OS(UO2²⁺, H6R^2-)} and K_{OS(UO2²⁺, H5R^3-)}].
These values were determined using the so called Fuoss equation for ion-pair fermation, and then its ratio was calculated to be 3.8-6.4. Consequently, the difference of the rate constants is approximately in agreement with that of outer-sphere association constants and can be explained merely by means of an electrostatic factor. The rate constant of water-exchange for uranyl ion was also estimated to be 3×10⁴s^-1. The temperature dependence of the rate constants was examined and the thermodynamic constants were calculated in each reaction path (Table 1).

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Experiments for the formose reaction, which was considered the formation process of sugar in the stage of chemical evolution, were carried out with an aqueous solution of formaldehyde and calcium hydroxide as a base catalyst by applying three different types of energy sources (wet discharge, ultraviolet irradiation (254 nm) and heat) and the effects of the energy sources on the sugar formation were discussed. The sugar product distribution was almost independent of the energy sources, however, the sugar yield was extremly high when the wet discharge was employed as an energy source. Moreover, when the initial concentration of formaldehyde was as low as 0.01 mol/l, the formose reaction still occurred by the wet discharge. Products such as glycolaldehyde, glyoxal and formic acid were formed in an aqueous formaldehyde solution by the both energy sources of wet discharge and ultraviolet irradiation. These results also revealed that formyl radicals play an important role in the sugar formation. In the formose reaction by the ultraviolet irradiation, other phenomena were found that the decomposition of sugars was inhibited, and the yield of sugars increased by the addition of the mercury (II) salt. Results in the present experiments suggested a possibility that the wet discharge and the ultraviolet irradiation would have an important effect on the prebiotic synthesis of sugars on the primordial earth.

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Correlation between the electrode processes and the electronic configurations on the reversible electrode potentials of ruthenium(II) 2, 2′-bipyridine complexes ([Ru(bpy)₂X₂] : where X₂ is bpy, (py)₂, (NH₃)₂, en, (CN)₂, (C₂O₄), gly, (acac) and (Cl)₂) have been studied. It has been found that ruthenium(II) 2, 2′-bipyridine complexes undergo one oxidation and two or three reduction proceses corresponding to reversible one electron transfer in nonaqueous solvents. According to the molecular orbital diagram, it is deduced that one electron is removed from the t_2g orbital of predominant metal character in oxidation process, resulting in the d⁵ low-spin state, while in the reduction process the electron enter π* antibonding orbital of predominant ligand character. It is found that the peak potentials are shifted according to the ligand attached directly to the central ruthenium(II) atom. The degree of potential shift in oxidation process is larger than in reduction process. In this systems the experimental results are in fair agreement with the relation expected from the molecular orbital diagram. A good linear relationship between the difference of oxidation and first reduction potential, ΔE₁*, and the lowest charge transfer energy, E_t2g→π* have been obtained.

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The ordinary velocity order of the migration of alkali metal ions is Li⁺>Na⁺>K⁺ with an eluent in a strong acid cation exchanger column, but the velocity order of the electromigration of alkali ions is K⁺>Na⁺>Li⁺ both in aqueous solution and in the cation exchange resin. The effective separation of Li⁺, Na⁺ and K⁺ may be realized by the simultaneous use of ion exchange and electromigration.
The equilibrium coefficients (to be RM/RH=1) of Diaion PK series (MR type) were measured between hydrogen ion and monovalent ions (Li⁺, Na⁺, K⁺, Rb⁺, Cs⁺, NH₄⁺). The effect of the degree of cross-linking on the equilibrium coefficients is similar to that for gel type ion exchangers. An electric field was applied to an ion-exchange column (Diaion PK 228, NH₄ form, height ; 105 mm, diameter ; 10 mm) in the reverse direction to the eluent (0.10 mol/l NH₄Cl) flow in each experiment for the separation of Na⁺ and K⁺. The effluent volumes required to elute Na⁺ and K⁺ were almost in proportion to the spended electric power. When a constant electric current (42 mA) was applied in the reverse direction to the eluent (at first 0.05 mol/l HCl 120 ml, at second 0.10 mol/l NH₄Cl) flow on a H form column (height ; 105 mm, diameter ; 8 mm), Li⁺, Na⁺ and K⁺ (0.32 meq., each) have been separated perfectly.

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The extraction of indium(III) from aqueous oxalic acid solution containing chloride ions with trioctylamine (TOA, R₃N) in xylene has been studied. The composition of the extracted indium(III) species has been investigated by several methods. The results obtained show that the mole ratio of indium(III) to oxalate in the complex is 2 : 3.
The chloroform solution of the extract was subjected to gel permeation chromatography (GPC). The chromatogram indicates that several species are present in the extract. Isolation of two species in the extract was carried out by preparative GPC. The chemical analysis of both isolated species implies that one of the species (species [a]) consists of indium(III), oxalate, chloride and R₃NH⁺ and the other (species [b]) chloride and R₃NH⁺. The mole ratio R₃NH⁺ : indium(III) : oxalate : chloride for the species[a] is 2 : 2 : 3 : 2. The species[a] was also confirmed by infrared(IR) spectra and elemental analysis. According to these investigations, it is concluded that the compositional formula of the species[a] is (R₃NH)₂In₂(C₂O₄)₃Cl₂ ; the formula is also supported by the thermal analysis. The empirical formula of the species [b] was estimated to be R₃NHCl on the basis of the mole ratio of R₃NH⁺ to chloride and IR spectrum. The molecular weights estimated by GPC suggests that both species [a] and [b] are present as aggregates in the chloroform solution.

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The reaction of thietane with hydrogen atom was investigated at 300 K and 2130 Pa using a conventional discharge flow apparatus.
In the wide range of conversion of thietane, propylene was mainly produced, and small amounts of ethylene, cyclopropane, propane and ethane were also obtained (Table 1). In the reaction of 3, 3-dimethylthietane with hydrogen atom, isobutene and 1, 1-dimethylcyclopropane were mainly produced (Table 2). These results are different from those of thietane-carbon atom systems, where cyclopropane was selectively produced.
When deuterium atom was used instead of hydrogen atom, propylene produced was found to be composed of C₃H₅D, which attained 85% of total propylene (Table 3 and Fig. 1). Since H-D exchange for thietane was not observed at all, deuterium atom of C₃H₅D was considered to be taken in either during or after propylene was formed. In order to make this point clearer, the reaction of propylene with deuterium atom was undertaken. It was found that H-D exchange for propylene did not proceed so rapidly and was accompanied with considerable deuteration and deuterolysis (Table 4). Since the ratio C₃H₅D/propane in propylene-D system was found to be much smaller than that in thietane-D system, it was concluded that deuterium atom of C₃H₅D was taken in during propylene was formed.
The reaction mechanism analogized from the similar, systems (thietane-C, thiirane-H, thiolane-H) was found not to be able to explain the above results. The following mechanism including allyl radical was proposed tentatively. The first step producing allyl radical is estimated to be exothermic (Table 5) and the second step
(CH₂)₃S + H → CH₂CHCH₂ + H₂S
CH₂CHCH₂ + H → C₃H₆* → C₃H₆
→ CHCH₂ + CH₃
is considered to produce a definite ratio of propylene and ethylene via chemically activated propylene (Table 6). The characteristic feature of thietane-H (or -D) system was able to be explained qualitatively by assuming the inclusion of allyl radical.
Based on the above reaction mechanism, the reaction of 3, 3-dimethylthietane with hydrogen atom is considered to go on a different reaction path because of the presence of two methyls. The reaction mechanism analogous to thiirane-H system seems to explain the main product isobutene.

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Synthesis of alkyl esters from monosubstituted methyl chlorides, carbon monoxide and methyl alcohol under various conditions has been studied kinetically in the presence of a catalytic amount of [Co₂(CO)₈]. By postulating a reaction scheme which could explain the experimental result satisfactorily, the rate equation has been derived as
V₀=(k₂k₃[Co]₀[RX]₀P_CO)/(k₂[RX]₀+k₃P_CO) (equation 15)
The rate constants of oxidative addition, k₂, and carbon monoxide insertion, k₃, have been determined (Table 5) and proved to be related with the Taft' σ* constants of the substituted groups.

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The separation of sodium oxalate from the by-products such as sodium benzenepolycarboxylates(NaBC) and sodium carbonate in the oxidation of Yallourn coal (C 66.8% d.a.f.) has been studied by using the difference of solubilities in sodium hydroxide solutions. Solubilities of sodium 1, 2-, 1, 4-, 1, 2, 4-, 1, 2, 4, 5-, and 1, 2, 3, 4, 5-, benzenepolycarboxylates in sodium hydroxide solutions (10-'25% NaOH), were measured, and the solubility product (K⁰_sp) of 1, 4-NaBC was calculated by the extended Debye-Hückel expression. The solubilities of NaBC except for 1, 4-NaBC were in the range 7.0-58.7g/100g-10% NaOH solution, decreased with the increasing concentration of NaOH, and were in the order : 1, 2, 4->1, 2->1, 2, 4, 5->1, 2, 3, 4, 5->1, 4- (Tables 2-6). 1, 4-NaBC was practically insoluble in 25% NaOH solution (Table2). The solubilities of 1, 4- and 1, 2, 3, 4, 5-NaBC were not very dependent on temperature (Tables 2, 6). Solubility product (K⁰_sp) of 1, 4-NaBC, (4.8×10^-4) was obtained using solubililies in NaCl solutions (Table 7, Fig. 1).
Sodium oxalate was separated from the actual oxidation products of Yallourn coal. The oxidation products (a mixture of sodium oxalate, sodium carbonate, NaBC, and other intermediates) (113 g) were washed first with 25% NaOH solution (150 g), and then, twice with 10% NaOH solution (100 g) (Fig. 2). The residue was washed with a small amount of water and dried. Thus, sodium oxalate was recovered 95% from the oxidation product, and the purity of crude sodium oxalate was 90% as it contained iron oxide, sodium carbonate and etc.

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Three series of new surface-active macrocycles (aminimide crown ethers ; [2], [4] and [6]) bearing aminimide group were prepared in the yields of practical use by treatment of the corresponding dihydroxy(aminimide)s ([1], [3] and [5]) with oligoethylene glycol ditosylates in THF in the presence of NaH (Scheme 1). Some aqueous solution properties and catalytic efficiency on the reaction of 1-bromooctane with saturated aqueous alkali metal iodides were examined for these aminimide crown ethers (AICE). The data were compared with those of several reference compounds (Scheme 2). AICE were easily soluble in water without the Krafft point and cloud point in the temperature range 0-100°C. Aqueous surface tension at critical micelle concentrations (CMCs) of AICE was cosiderably low (33-37 dyne/cm) (Table 2). CMCs of AICE were much higher than those of alkyl crown ethres [8] and were similar to those of N-alkyl monoazacrown ethers [9] (Fig. 1). Among three series of AICE, [2] having the aminimide group separated from the crown residue had higher CMCs and showed more pronounced alkyl-chain length dependence of CMCs than those of [4] and [6] having the aminimide group inserted partially or wholly into the crown part (Fig. 2). With respect to thecatalytic action, [4] and [6] had high efficiency despite the larger hydrophilicity, and they exhibited greater selectivity for alkali metal ions than that of "dicyclohexyl-18-crown-6" (Table 3). The results are discussed in terms of the structural effects on the complex formation and from the viewpoint of the hydrophliic-lipophilic balance of the catalyst-salt complex formed in the reaction phase.

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Syntheses of triarylmethanes by the condensation of aniline derivatives with benzaldehyde were studied by the use of H-form ion-exchange resins (Nafion-XR and Amberlyst-15) in place of the commonly employed Brφnsted or Lewis acids. In a typical run, a mixture of oanisidine (0.15 mol) and benzaldehyde (0.05 mol) was heated at 155-158°C for 6 h in the presence of Nafion-XR. The optimum amount of the catalyst in the above reaction was 30 wt% on benzaldehyde for formation of the condensation product. Its yield reached to 92.3%. Examination of HPLC revealed that two components were contained in the product in a ratio of 89.1 : 10.4%. The main product (89.1%) and by-product (10.4%) were identified as 4, 4′-diamino-3, 3′-dimethoxytriphenyl methane and its isomer, respectively, by means of their NMR, UV, elemental analysis and color-development test. Similar condensations of various aniline derivatives with benzaldehyde produced the corresponding triarylmethanes. Steric hindrance by substituents in the aniline derivatives affected the yields and the isomer ratios of the products. Catalytic effect of Amberlyst-15 was usually not so good as those of Nafion-XR under similar reaction conditions.

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The phenolic sesquiterpene xanthorrhizol, 5-(1, 5-dimethyl-4-hexenyl)-2-methylphenol[1a] was synthesized through a new synthetic route, and the cyclization of its intermadiate was investigated. Starting from 4-(p-toluoyl)butyric acid [7], 2-methyl-6-(3-hydroxy-4-methylphenyl)-2-heptanol [4a] and its methyl ether [4b] were synthesized via 5-(3-methoxy-4-methylphenyl)hexanoic acid [12b]. [1a] and its methyl ether [1b] were obtained by dehydrating [4a] and [4b] with SOCl₂ or POCl₃, respectively. The dehydration of [4] with formic acid yielded [1] along with 8-hydroxy-ar-himachalene [14a] or its methyl ether [14b]. By heating with p-toluenesulfonic acid [4b] afforded a mixture of dihydroxanthorrhizol methyl ether [15b], 5-methoxycalamenene [16b] and 7-methoxycalamenene [17b]. The cyclization of [4b] with HBr gave a mixture of the phenolic compounds [15a], [16a] and [17a]. These results indicate that [14] was isomerized to [16] and [17] with an acid catalyst such as p-toluenesulfonic acid or HBr. Each of hydroxy- and methoxycalamenene [16] and [17] was a diastereomer mixture consisting of about cis-isomer 20% and transisomer 80%. Dehydrogenation of [17a] and [17b] gave 7-hydroxycadalene [18a] and its methyl ether [18b], respectively.

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Pentaerythritol derivatives such as mono-, di-, tri- and tetraesters of 2-ethylhexanoic acid, and mono- and dibenzylidene ethers were prepared as additives for PVC. These materials were mixed with DOP (20 phr) and Zn stearate/Ca stearate (2/1) (3 phr) at 150°C for 10 min using an open roll. Compounded PVC films were heated at 160°C up to 120 min in a circulating air oven to examine the synergetic effects of these materials on inhibiting zinc burning, so-called stabilization of PVC.
1) Monobenzylidene ether, mono- and diesters in the coexistence of metal soaps slowed down the appearance of zinc burning and prolonged good initial color of PVC films. The synergetic effects would be attributable to the formation of the colorless complex between two hydrxyl groups in the molecules and zinc chloride formed.
2) Mono-O-(2-ethylhexanoyl)pentaerythritol showed the greatest synergetic effects among these materials, and had a good solubility in PVC-DOP. Therefore, it can be used practically as a secondary stabilizer instead of pentaerythritol with Zn/Ca soaps.

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In order to reuse waste paper pulp (WP) and synthesize an effective adsorbent for metal ions and dyes, 2-(dimethylamino)ethyl methacrylate (DM) was graft-copolymerized onto the WP containining lignin (22.7%) and cellulose by the method previously reported. The removal of metal ions from aqueous solution by adsorption on the WP-DM graft copolymers (WPG) was investigated in a batchwise operation. The order of the amount of adsorbed metal ions at pH 4-6 was Cr⁶⁺>>Fe³⁺>Cu²⁺>Hg²⁺>Pb²⁺>Cd²⁺>Zn²⁺. The amount of the adsorbed Cr⁶⁺ was 1. 4 mmol/g WPG in the case of 20% (cationic group 0.76 mmol/g) grafting WPG. The adsorption efficiency of the copolymer of low degrees of grafting was higher than that of high degrees of grafting. For example, 5 anions (e.g., HCrO₄^-) were adsorbed on one cationic DM in case of 5% (cationic group : 0.22 mmol/g) grafting WPG. The adsorption isotherm was found to be Freundlich type, e.g., m=13.1C^0.41. The adsorption of Cr⁶⁺ on the WPG took one hour to reach equilibrium at pH 1-4.5. Adsorbed Cr⁶⁺ on the WPG was easily eluted by 1 mol/l NaOH.

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Substituent effects on the ozone decoloration reactions of 1-(m-substituted phenylazo)-2-naphthol-3, 6-disulfonic acids in aqueous solutions were investigated. The relationship between the logarithm of the decoloration rate and the index (pK_OH, or σ_m value) of the basicity of the dye (Fig. 4, 5) indicates that the decoloration reaction proceeds by nearly the same mechanism as that of the ozonolysis of monosubstituted ethylene. The effect of the change in keto-enol ratio of the dye on the ozone decoloration reaction (Fig. 6) suggests that, of their two tautomeric isomers, the ketohydrazo-form plays a dominant role. From these results, it seems likely that ozone attacks the CN^α bonds of the ketohydrazo-forms of the dyes.

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From 2, 4-diphenyl-1-butene, a thermal decomposition product of waste polystyrene, 2, 4-diphenylbutyl 2, 4-diphenylbutyrate (DPBB) was synthesized and its thermal stability was examined by thermogravimetric analysis. Poly (vinyl chloride) (PVC) sheets containing DPBB and/or bis(2-ethylhexyl) phthalate (DEHP) and also a stabilizer were prepared and their mechanical and some physicochemical properties were examined.
It was found that ( 1 ) the thermal stability of DPBB was higher than that of the typical plasticizers for PVC, such as DEHP and dibutyl phthalate, ( 2 ) the PVC sheets plasticized with DPBB also showed high thermal stability, and ( 3 ) DPBB did not interrupt the effect of DEHP on compatibility with PVC.
High thermal stability of DPBB may be due to the inhibition of formation of six-membered-ring transition state in the cis-elimination reaction by the introduction of phenyl groups onto β-carbon atom in alkyl chains.

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The measurements of the longitudinal relaxation time (T₁) and the computer simulation were carried out in order to investigate the comformations of the complex formed among copper chlorophyllin (Cu-chln), poly(N-vinylpyrrolidone) (PVP) and adenosine-5′-monophosphate (5′-AMP). It was found that T₁′s of all the protons of 5′-AMP except H₈ decreased by the formation of Cu-chln-PVP-5′-AMP complex. The comparisons of the observed T₁′s with the results of the computer simulations have led to the conclusion that the adenine ring is parallel to the chlorine ring. The conformation of the Cu-chln-PVP complex was also discussed.

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The electrochemical behavior of bis (hexafluoroacetylacetonato) nickel(II) was studied in 0.05 mol·dm^-3 TBAP-DMSO or 0.1 mol·dm^-3 TBAP-DMSO by differential pulse polarography and cyclic voltammetry. In the previous paper, it has been reported on the basis of the conductance data that [Ni(hfac)₂] in DMSO is involved in the chemical equilibrium (1).
[Ni(hfac)₂] ←→ Ni(hfac)⁺ + hfac^- (1)
The dissociation of [Ni(hfac)₂] in the bulk of the solution was also supported by cryoscopy in this paper. The following electrode reaction mechanism was presumed :
[Ni(hfac)₂] + 2e → Ni(hfac)₂^2- (2)
Ni(hfac)⁺ + 2e → Ni(hfac)^- (3)
Ni(hfac)₂^2- → Ni(hfac)^- + hfac^- (4)
Ni(hfac)^- → Ni⁰ + hfac^- (5)
where k₁ and k₂ denote the rate constants of the dissociation reactions (4) and (5), respectively.

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Prepration of calcia-stabilized zirconia powders by spray-pyrolysis technique and their sinterabilities were investigated. The spray-pyrolysis of ethanol-water (2 : 1 in vol.) solution of ZrO(NO₃)₂ and Ca(NO₃)₂ at 950-1150°C gave cubic-ZrO_2ss(CaO : 15, 20 mol%) or tetragonal-ZrO_2ss(CaO : 10 mol%). The powders consisted of hollow or flake particles (1-5μm). The sinterability of 15 mol% CaO powders showed a maximum at the spray-pyrolysis temperature of around 1050°C and tended to increase with an increase in the concentation of spray solution. The powders prepared by pyrolysis of the solution with [Ca²⁺ + ZrO²⁺] > 0.55 mol/l at 1050°C gave sintered bodies with relative densities above 90% by firing at 1500°C for 2 h.

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The Cr(VI) in an acidic solution was reduced to Cr(III) and was most efficiently adsorbed at pH about 5 by the retorted shale from Thailand oil shale (spent shale). It is considered that these behaviors of Cr(VI) in an aqueous solution is due to the action of the deposited carbon in the spent shale, which was activated with various salts of Ca, Mg, Na, K and the like during the retorting of the oil shale.

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