Regarding the standard entropy and enthalpy of solution of gaseous solutes in solvents, δS°_s and δH°_s, Abraham's linear equations are examined to clarify the significance of th e solute parameter R_HS, and the solvent parameters. On the basis of a previous work on ionic hydration, J. Phys. Soc. Jpn.55, 1021(1986), an effective solute radius re=2r_sw(δS°_{s, m}/δS°_cw)^1/2 is introduced after discussing the correlation between δS°_sx. and the square of the van der Waals b radius rb. Here the subscripts m and x of δS°_s denote the scale of molality and of mole fraction, δS°_cx is the standard entropy of condensation of water vapor, -118.8, J.mol-1.K-1 at 298 K, and r_sw is the Stokes radius of water, 1.07×10^-8cm at 298 K. It is found out that r_e² just equals 2 R_HS. The effective area r_e2 can be extensively used in nonaqueous solvents. Referring to solutes and solvents treated by Abraham, δS°_{s, x}, δH°_s, and the standard Gibbs energy of solution δG°_sx can be expressed as linear, equations of r_e², with coefficients B_S and B_H and constant terms A_S and A_H characteristic of solvents. Effec tive solute radii r_e.o at δG°_{s, x}=0 are calculated for 28 solvents by using individual values of A_H, A_S, B_H, and B_S. For water alone, there is no real value of re.o. For 27 nonaqueous solven ts, the averaged value of r_e.o is (2.56±0.20)×10^-8 cm, by which an averaged nonaqueous solvent is discussed. An excess amount of δG°_{s, x}, for water from that for the averaged nonaqueous solvent is attributed to the hydrophobic hydration of solutes.

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The thermal decomposition of platinum chlorides was investigated by TG and DTA and characteristics of the Pt-coated electrodes were discussed. Both crystals and aqueous solutions of H₂PtCl₆.6H₂0 and PtCl₄.5H₂0 were decomposed firstly into PtCl₂ and finally into Pt^o of which forming temperatures were 330°C and 530°C, respectively. On the other hand, the TG curve showed that Pt(IV) was reduced to Pt^o at about 400°C when Pt(IV) was dissolved in butyl alcohol (n-BuOH). Titanium/Pt electrodes with large roughness were tentatively prepared by applying H₂PtCl₆-n-BuOH solution on Ti bases and heating even at lower temperature (300°C). The roughness was, however, lowered gradually as the heating temperature was risen. When the electrodes were prepared at higher temperature, the Ti/Pt joining points were better sintered and the exposed Ti, surface was also better protected against corrosion by formation of titanium(IV) oxide, so that the lifetime of the electrodes could be prolonged. Other organic reagents were examined as the solvents and it was concluded that the thermal decomposition of Pt(IV) in the organic reagents takes place readily via the redox reaction of a Pt(II)-complex.

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A new type sensor was constructed for the measurements of ozone, one of major photochemical oxidants. Ceramic tubes were coated with dilute aqueous metal nitrate solutions and heated in a furnace to form the thin films of transition metal oxide (Co₃0₄, CuO, Mn0₂, and NiO). The electric resistance of the thin films was measured when they were exposed to ozone. The responses were related with the adsorption process. The conductivity of an n type semiconductor, Mn0₂, decreased, and those of p type semiconductors, Co₃O₄, and NiO, increased as shown in Table 1. Thus ozone is adsorbed to the metal oxide films as an electron acceptor. The electric conductivities varied with the time and did not reach constant values. Fig.5 indicates that at constant ozone concentration the conductivity of the Co₃0₄sensor varies with the O.6 th power of the time at 0°C. The conductivity of the Co₃0₄sensor depended on the O.6 th power of the ozone concentration at a constant reaction time (Fig.6). The conductivity of the Co₃0₄ sensor increased by 20% of its original value when the sensor was exposed to O.06 ppm ozone (the environmental quality standard of photochemical oxidants) for 50 min. Thus the sensors are sufficiently sensitive for practical environmental analysis of, 'ozone. Water vapor affected the conductiliity. of the Co₃0₄ sensor (Fig.9). The sensitivity to water is 10^-4-10^-5 times of that to ozone, and it may not be neglected in the field measurements.

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The Indium Tin Oxide (ITQ)/p-Si heterojunction electrode was coated with polyaniline and its derivatives in order to improve the durability of photoerectrochemical (PEC) cells composed of ITO/p-Si electrode. ITO (containing 5 wt% SnO₂) was evaporated by an electron beam evaporator, onto Si substrate. Conducting polymers were prepared by galvanostatic electropolymerization on ITO/p-Si at 10 μA.cm_-2. A 500 W Xenon lamp with an infrared filter was used for illumination. Although the quantum yield and the energy conversion efficiency of the PEC cell using the polymer-coated electrode were reduced by its higher resistance and photoabsorption of the polymer itseli. However, the stability of the PEC cell was greatly improved. Particularly, th e photocurrent of the PEC composed of ITO/p-Si coated with polyaniline was found to be less, than 20% degradation of the' initial current value after 100 h photoirradiation.

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Since some photocatalytic activities have been observed for the complex oxides of Ti, Zr, and Hf, it has been aimed in the present report to find if the corresponding complex oxides of rare earth elements have similar activities or not. SrDy₂0₄, SrY₂0₄, Sr₂Ce0₄, SrCe0₃, and SrSm₂0₄ were synthesized and were treated in CS₂, and 0₂ atmospheres at elevated temperatures. Those synthesized with NiO and those without NiO were tested for the comparison'of their catalytic activities using t 1:1 CH₃OH/H₂0 and O.24 moldm^-3 Na₂S/H₂0 as reactants. The photocatalytic activities observed from those complex oxides, which were treated by CS₂-0₂ cycles, were comparable to those of Ti, Zr, or Hf. A particular point observed fro m rare earth catalysts is that they are found to be effective for generating hydrogen without NiO as Co-catalyst. Such capability of rare earth oxides may be explained by their small electronegativities.

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The oxidation process in slurries of calcium sulfite hemihydrate to α-calcium sulfate hemihydrate at 125°C and 2kg/cm2 was examined. After the pH value of the calcium sulfite hemihydrate slurries was adjusted to 9, 4 or 3, the slurries was heated from room temperature to 125°C and then oxidized with air at 125°C. The concentrations of sulfite and sulfate ions in the liquid phase, and the convertion rate of calcium sulfite hemihydrate to α-calcium sulfate hemihydrate in the solid phase, were determined.
Calcium sulfate dihydrate formed during the heating process of the slurries was converted to α-calcium sulfate hemihydrate at 125°C. When calcium sulfate dihydrate disappeared in the solid phase, α-calcium sulfate hemihydrate was precipitated without the formation of calcium sulfate dihydrate.
The overall ra te of conversion from calcium sulfite hemihydrate to α-calcium sulfate hemihydrate in slurries was controlled by the dissolution rate of oxygen. to the slurries, the dis, solution rate of calcium sulfite hemihydrate in water, the oxidation rate of sulfite ions to sulfate ions in the liquid phase, and the precipitation rate of α-calcium sulfate hemihydrate from the liquid phase. The dissolution rate of calcium sulfite. hemihydrate into water appears to affect the overall reaction rate.

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A method of preparing tin chelate compounds using bis(acetylacetonato)copper(II) [Cu (acac)₂], bis(dibenzoylmethanato)copper(II) [Cu(dbm)₂], and bis(ethyl acetoacetato)copper(II) [Cu(etac)₂] has been investigated.
Tin(II) chloride (SnCl₂) reacts with [Cu(acac)₂] in a molar ratio of 2: 1 to give an oxidative addition product [SnCl₂(acac)₂] and a partial replaced product [SnCl(acac)]. Similar results were also noted in the reaction between SnCl₂ and [Cu(bdm)₂]. However, only the corresponding oxidative addition product, [SnCl₂(etac)₂], was isolated from the reaction of SnCl₂ with [Cu(etac)₂] under the same reaction conditions.
The equimolar reaction of SnCl₂ with [Cu(acac)₂] afforded the oxidative addition product and bis(acetylacetonato)tinan [Sn(acac)₂], together with the formation of a trace amount of [SnCl(acac)] as the reaction products. The mechanism for the formation of these products is discussed.

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Electrolyte cobalt (III) complexes with quadridentate dioxime, formulated as [Co(Hbhen)B₂]Cl₂ or [Co(Hbhpn)B₂]Cl₂ were isolated, where dioxime ligand H₂bhen was N, N'-bis(2-hydroxyimino-1-methylpropylidene) ethylenediamine and H₂bhpn was N, N'-bis(2-hydroxyimi-no-1-methylpropylidene)-1, 3-propanediamine, while B was aniline or its derivatives, and X was Cl-, Br-, or I- ion. Thermal decomposition of these complexes was also studied in the solid state by thermogravimetry (TG) and differential thermal analysis (DTA).
An endothermic phenomenon was observed at the first stage of therma l decomposition of these complexes. The analytical studies on the infrared and electronic spectra of therma l decomposition products revealed that the endothermic phenomenon was due to the replac ement of axial ligand (base B) by the outer-sphere anion. It was found that a new green compound was formed as the replacement product at the first thermal decomposition of [Co(Hbhpn)B₂]X₂complex. The electronic, infrared, and X-ray photoelectron spectra of the green compound suggest that the constitutional formula is [CoX₂(Hbhpn)].

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Photodegradation of tributyltin chloride (TBTC) in sea water by irradiation with ultraviolet light has been investigated by means of gas chromatography equipped with an electron-capture detector (ECD-GC). For ultraviolet light irradiation was used Fadometer (Model: Mitsubishi MH-1, high pressure mercury vapour lamp: H 400-F, main wavelength: 365 nm, intensity: 8.68 x 103 μW/cm²). After irradiation, the residue of TBTC in sea water was extracted into hexane and measured by gas chromatography. Recoveries of TBTC from sea water sample were 93-97%-at 1.2 μg/ml and the relative standard deviation of peak area (n=5) was 3.3%. From this photod. egradation work, the half-life of TBTC in sea water was estimated to be 257 h (about 11 d). It was, suggested, that TBTC in sea water was decomposed to other butyltin compounds such as di- and monobutyltin compounds by irradiation with ultraviolet light.

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3-(Hydroxymethylene)camphor, the enol of 3-formylcamphor, was allowed to react with ethyl glycinate to give aminomethylene compound. The alkylations of the compound with methyl iodide and benzyl chloride in the presence of LDA afforded L-amino acids in low asymmetric yields such as Ala (9.2% e. e.) and Phe (4.3% e. e.), respectively.
On the other hand, D-N-methylalanine (43.3 % e. e.) and D-N-me thylphenylalanine (26.5% e. e.) were obtained by the same alkylations when ethyl N-methylglycinate was used instead of ethyl glycinate. Thus pronounced effect of N-substituent of glycine was observed.
exo-3-Formyl-3-methylcamphor was prepared and allowed to react with ethyl glycinate to give Schiff base. The Schiff base would be expected to activate the methylene group of glycine moiety and to increase the enantioselectivity by 3-methyl group of camphor moiety. The alkylations of the Schiff base with methyl iodide, benzyl chloride and isobutyl iodide gave L-Ala (70.2% e. e.), D-Phe (84.7% e. e.) and L-Leu (71.6% e. e.), respectively. And the alkylations with sec. alkyl halides were also examined.

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Products distributions in nitration of dibenzofuran (DBF) have been examined in detail under 35 reaction conditions. Each condition has been evaluated from the view point of the yield of nitrodibenzofuran.3-Nitrodibenzofuran was selectively prepared under the following nitration conditions (nitrating reagents, molar ratio to DBF, reaction temp., time, and the yield by GLC): 99% HNO₃ in AcOH, 12, RT-95°C, 1h, 79%; 99% HNO₃ in CF₃COOH, 1.2, 0°C, 1h, 89%; and 65% HNO₃ in 65% H₂SO₄, 50-400°C, 4h, 69%. On the other hand, 2-nitrodibenzofuran was obtained as a major product (47% yield) in the reaction of DBF with 1-cyano-1-methylethyl nitrate/AlCl₈ (1.2 equiv.) in nitromethane at 25°C for 1h. The isomer distribution in the nitration products of DBF has been determined. under the controlled reaction conditions, low conversion and no formation of dinitrodibenzofurans. The distribution order 3>2>1>4 was observed in nitration with HNO₈, while, 2>3>1>4 with alkyl nitrate/Lewis acid or NO₂BF₄. Comparing with isomer distributions for other electrophilic reactions of DBF, the positional reactivity has been discussed by the nature of transition state of the nitration.

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The Ullmann-type homocoupling of aryl sulfonates to biaryls has been studied with the low valent nickel catalysts generated in situ from nickel(II) chloride, triphenylphosphine, sodium iodide, and zinc powder under ultrasounds irradiation in N, N-dimethylformamide. The reactivity of aryl sulfonates examined increased in the following order: methanesulfonate<p-toluensulfonate<trifluoromethanesulfonate. This reaction was compatible with a variety of functionalities such as ketone, ester, amide, and nitrile. Yields dropped with 2-substituted aryl trifluoromethanesulfonates and further to no reaction with 2, 6-disubstituted ones. Irradiation of ultrasounds effectively accelerated the reaction to he able to reduce the reaction time to half in certain cases compared to the ordinary magnetic stirring.

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Effect of protic solvents such as methanol on the pyrolysis of S-ethyl-S-phenyl-N-tosylsulfimide (SN [1]), S-ethyl-S-2-pyridyl-N-tosylsulfimide (SN [2]), and 2-(N-tosylethanesulfinimidoyl)pyridine 1-oxide (SN [3]) were studied in comparison with those of aprotic solvents, benzene and 1, 4-dioxane.
The relative rate in benzene: 1, 4-dioxane: methanol for the pyrolysis of SN (1) was 8.5: 5.5: 5.1 at 100°C. The activation parameters of SN [1] in methanol were Ea=115.1kJ/mol and ΔS&^ne;=-41.0 J.K-1mol-1. The E_a value was similar to that for SN [3] or S-phenyl-S-(1- and 2-phenylethyl)-N-tosylsulfimides [4] whereas ΔS&^ne; was about 1/5 that for SN [3] The isotope effect in methanol, k(_MeOH)/k(_MeOD), on the pyrolysis rates of SN [1]was about 0.82, while those of SN [2] and SN [3] were found to be nearly unity. The relations between log [MeOH] and log k for SN [1] and SN [3] gave straight lines with slopes of -O.45 and -O.58, respectively. The substituent effects gave linear Hammett correlations with a positive slope in all solvents. The ρ-values were O.792 in benzene, O.809 in 1, 4-dioxane and 0.851 in methanol. The retardation of the pyrolysis of sulfimide in the protic solvent may be ascribed to the formation of hydrogen bond between the protic solvent and the nitrogen atom of sulfimide function, of the substrate in the ground state.

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The preferential conformation of (o-substituted phenyl)ferrocenes were discussed by the method of 'H-NMR. On (o-hydroxy- and o-alkylphenyl)ferrocene, the bond between phenyl group and cyclopentadienyl group as twisted and steric conformation in which the substituent was situated on the endo position (Fig.2 and 4) was preferred. In the case of (o-chloroand o-nitrophenyl)ferrocene, exo position was preferred. On the other hand, the preferential conformation of (2-chloro-6-methyl- and 2-methyl-6-nitrophenyl)ferrocene was assumed to be twisted as well as (o-substituted phenyl)ferrocenes. But in the preferential conformation of (2, 6-dimethylphenyl)ferrocene, the steric hindrance was, avoided. by vent of bond angle between phenyl group and cyclopentadienyl group (Fig.5). The driving forces were considered as follows: (i) van der Waals repulsion between a-proton in cyclopentadienyl group and ortho-substituent (ii) interaction between the d electrons of iron atom in ferrocene and ortho-substituent.

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For the purpose to investigate causes of uremia from view of chemical substances, studies were done to identify specific chemical components in plasma of patients with chronic renal failure. As reported previously, we have found a chromatographic peak (peak 2a) specific to uremic plasma and showed possibility of the peak to contain uremic toxins. In, this paper, the peak fraction was further fractionated to UV-absorbing subpeaks and subjected to identify their components. As a result, 10 components summarized in Table 1 were clarified and their possibilities as uremic toxins were discussed. Among them, 2-deoxy-2, 3-dehydro-Nacetylneuraminic acid [1], N²-phenylacetylglutamine [3] and quinolinic acid [4], known to be human metabolites, were likely to act as uremic toxins from their biological activity.4-[[(Carboxymethyl)amino]carbonyl]phenyl β-glucopyranosiduronic acid [5] was noteworthy as its orthoisomer was found in uremic fluid by L. Zimmerman, et al. and P. Gallice.

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New isopropenyl-1, 3, 5-triazines, e. g., 2-(amino or anilino)-4-(N-methyl-, ethyl- or butylanilino)-6-isopropenyl-1, 3, 5-triazines [1]-[5] were prepared. The homopolymerization of thesme monomaenrs and cropolmerizations with syrene, nethmyl methacrylate and mathylate (M₁) were carried out using azobisisobutyronitrile, as an initiator. The copolymerization parameters (r₁ r₂ Q₂ and e₂) were determined for these monomers. Thermal polymerization of these monomers was studied by differential scanning calorimetry (DSC). The ceiling temperature (T) and the heat of polymerization (ΔH_p) were obtained from DSC data, These ΔH_p and T_e values are in good agreement with those measured by the equilibrium monomer concentration determined by isothermal DSC. These monomers form ed glassy state when rapid cooled after melting. Some discussion was made, about the glassy state of the polymer-monomer system.

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An encapsulation process of magnetic metal particles was investigated for the purpose of manufacturing powder cores for electronic power devices. The following two points were essential in this encapsulation process: the polymer particle attachment to the metal particle surface by static electrification. and the filming process from latex.
A latex contaning 0.5 μm polystyrene particles was mixed with powdery Fe-1%Si alloy (44-74 μm) to obtain a well-dipersed state. This polymer particle-attached powder was h eattreated for 30 min at 180°C to transform the polymer particles into a thin film. The metal particles were thus encapsulated in a uniform film.
The polymer particle-attached powder (Capsule A) and the film-encapsulated powder (Capsule B) were compacted at 600 MPa pressure to yield powder cores(Core A and Core B). Magnetic measurements on these cores indicated that the permeability for Core A decreas ed in higher frequency range. According to SEM observation for core fracture, polymer particles were partially lost from the metal surface by the friction force during compaction. On the other hand, Core B had good frequency characteristic and low iron loss. The reason was that the film, having a high deformation ability and adhesive force to the metal surface, was not exfoliated by the friction force, and remained as a sufficient insulator between metal particles. A magnetic powder core, having a high metal volume fraction, has been thus manufactured.

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Several kinds of poly[(alkylaminomethyl)styrene]beads were synthesized and their pro-perties were examined as stationary phases of high-performance liquid chromatography. Separation behaviors of some aromatic compounds were studied with these b e ads, and it was clarified that the retention time of more hydrophobic compound is longer than that of l ess hydrophobic one These results imply that the polymer beads are available as a stationar y phase of reversed phase chromatography. But the effect of hydrogen bonding betw een the secondary amino groups of the stationary phase and a protic solvent such as water is n ot negligible and hydrophilic layer formed around these amino groups becomes important wh en the length of alkyl chain is short, and results in a longer retention time for more hydrop h ilic compound.

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An adsorption of metal ions on the Dowex chelate resin A-1 was examined by means of a batch and column methods in the presence of magnetic field. Metal ions used were Fe(III), Ni(II), Co(II), Cu(II) and Zn ions. Magnetic flux density was 0.12 T (batch metho d) and 0.2 T (column method). An amount, velocity and rate of adsorption were increased by the magnetic field effects. The velocity of adsorption increased by about 3-50% compared with their values in the absence of magnetic field by a batch method. Most efficient concentration of metal ion was about 0.1 mg/cm3, and that of flow rate was 30 cm3/min (Fe(III), Ni(II) and Cu(II) ions), 20 cm3/min (Co(II) ion), and 45 cm3/min (Zn ion) by a colum n method. The adsorption rate increased by about 1-11% compared with their values in the absence of magnetic field. Fe(III) ion was 1.0-6.5%, Ni(II) ion was 7-11%, Co(II) ion was 1.0-2.2%, Cuan was 0-2.0%, and Zn ion was 4.0-9.0%. The adsorption amount per unit mass of the resin increased by about 1-6% by both methods in the presence of the Magnetic field. It was assumed that the magnetic field effects was the cost down on the working operations.

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γ-Irradiation led to decoppositien of CHCl₃ with the G-value (G(-CHCl₃)) of 1.8 to produce CO₂ in a He-saturated aqueous solution. The yield of CO₂ was nearly equal to half amount of the consumed CHCl₃. In the N₂0-saturated systein, the G(CHCl₃) value was 2.2 and 3/4 molar amount CO₂ was preduced per 1 mole of CHCl₃, consumed The deecomposition of CHCl₃ was enhanced by the addition of HCOONa to both the He-and N₂0-saturated systems. In the presence of 500 times excess amount of HCOONa, the G(-CHCl₃) values were increased by 6.5 times in the He-saturated solution and 4.2 times in the N₂0-saturated solution. In the lower concentilation range of HCOONa the main radiolysisp roduct was CHCl₂CHCl₂. Upon increasing the concentration of HCOONa, the yield of CH₂Cl₂ increased, while that of CHCl₂CHCl₂ decreased.

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The microwave spectra of 2-methylpyridine 1-oxide and 2-methyl-d₃-pyridine 1-oxide were observed in the frequency range from 16 to 34GHz. The transitions of the ground state a-type R-branch, b-type R-branch, and b-type Q-branch were assigned and the followingrotational constants for the ground state were determined: The I_c-I_a-I_b value of the principal moments of inertia calculated from the above rotationalconstants is_-3.12uA² for the normal species, and -6.20uA² for the methyl-d₃ species. These values indicate that the molecate frame of CH:CHCH:CHC(CH)N→O is planar.

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exo-3-Formy1-3-methylcamphor was synthesized by a following route, for the purpose of asymmetric alkylation of glycine.
Methyl 3-methyl-3-camphorca rboxylates [4] were obtained by the methylation of methyl 3-camphorcarboxylate [3] with sodium hydride and methyl iodide in good yield. The products were separated into two parts by treating with ligroine, i. e. a crystalline part [4a](mp 88-48.5°C) and an oily one [4b]. It was found that the structure of [4a] was determined as exo-3-carboxylate and that of [4b] was as endo-one by the analyses of their NMR data. The reduction of [4a] with LiAlH₄ gave diol[5] And exo-3-formy1-3-methylcampho r was obtained as a slightly unstable liquid (bp 123°C/13 mmHg, [α]_D²⁰ 162.5°) by the oxida-tion of [5] with Collins' reagent.

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Oxy-Cope rearrangement of 4-vinyl-1, .6-heptadien-4-ol [1] at 330°C gave 1, 8-nonadien-4one [4] along with 2, 8-nonadien-4-one [5]. The ketone [4] was converted to the title compound [2] as a mixture of (E)- and (Z)-isomers, by the treatment with LDA and, trimethylsilyl chloride. Alternatively the nonatriene [2] was prepared selectively by the anionic oxy-Cope rearrangement of [1] followed by quenching with trimethylsilyl chloride. Intramolecular Diels-Alder reaction of [2] afforded only cis-3 a-trimethylsiloxy-2, 3, 3 a, 6, 7, 7 a-hexahydro-1 H-indene [3], irrespective of the stereochemistry of [2].

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