As a result of electrostatic interaction at the air-water interface, a stable monolayer of a charged amphiphile was formed on an aqueous solution of a counter charged polyelectrolyte. The polyion-complexed monolayer could be transferred on a solid substrate as LangmuirBlodgett films. The pressure-area isotherm of the polyion-complexed monolayer was strongly dependent on the chemical structure of the polymer. Morphological studies of the in situ observation of the surface monolayer by a fluorescence microscope indicate that the surface chemistry of the polyion-complexed monolayer was affected by charge density of the polyelectrolyte, flexibility of the polymer main chain, flexible hydrophilic spacers in the polymer chain, steric and hydrophobic interaction with the polymer side chain, etc. The redox potential of the LB film of the water soluble viologen amphiphile was strongly affected by pH when the monolayer was prepared on an aqueous poly(acrylic acid) solution. Stoichiometric ion pair formation in the complex LB films estimated by elemental analyses using X-ray photoelectron spectroscopy and adsorption kinetics of the polyelectrolyte to the surface monolayer observed by an ATR (attenuated total reflection) technique using SPP (surface plasmon polariton) resonance strongly suggest that the counter charged polymer must be regularly bound to the charged surface of the monolayer. LB films prepared by the polyion complex technique were applicable to an electrochemical catalyst of an enzyme reaction, an optical ion sensor, and a photoelectrochemical cell.

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Liquid phase oxidation of cyclohexene with 02 has been studied using Pd-supported heteropoly compounds and homogeneous catalysts. A Pd-supported Cs2.5110.5PMo6W040 was found to be efficient for the catalytic oxidation of cyclohexene to produce cyclohexanone (Wacker-type oxidation) and cyclohexenone (allylic oxidation), whereas PdC12-CuCl2 showed a very low activity under the same conditions. While the activity of Pd-supported Cs2.5H0.5PMo6W6040 decreased during the reaction, it was recovered by the heat treatment of the catalyst powder in helium or hydrogen. From the time course of the products and 02pressure dependence, it was shown that the two products were formed through a parallel reaction. At 80 °C and 8 atm of 02, turnover frequency (TOF) for the total products reached about 25 on the basis of Pd atom, which is greater than that for a homogeneous Pd(NO3)2-H3PMo6W6040 system. The rate of the formation of cyclohexenone (a llylic oxidation)was influenced by the pretreatment conditions. On the other hand, the rate for cyclohexanone (Wacker-type oxidation) was insensitive. These results support the different active sites for the two reactions.

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Activataed carbon is widely used as the adsorbent and the catalyst of oxidation. However, there are little studies about the reduction reaction by activated carbon. In this paper, the effect of the solution conditions and the pretreatment of activated carbon on the reduction of Fes+ was investigated. The experiments were carried out as follows: Activated carbon was added to the HC1 solution containing Fes+ and the time course of Fe2+ concentration was measured by o-phenanthroline method. When the reaction was carried out in an atmosphere of nitrogen, activated carbon was added to the HC1 solution and degassed with an aspirator and then Fes+ solution was added after passing the N, gas. In the presence of dissolved oxygen, the time course of Fe2+ co ncentration displayed a maximum curvature, but it displayed increasing curvature in an atmosphere of nitrogen (Fig.2). Consequently, activated carbon can reduce Fes+ to Fe2+ in the presence or absence of dissolved oxygen and oxidize Fe- to Fes+ if oxygen is dissolved. Reducing ability of the activated carbon decreased by th e acid treatment in the presence of oxygen (Table 2, Fig.3) and by the Fes+ treament (Fig.6). However, reducing ability was restored by drying the treated carbon (Figs.4, 5, 6) and the degree of restoration of reducing ability increased with an increase in the drying temperature (Fig.4). Initial reduction rate was not affected by the presence of dissolved oxygen (Fig.7), Fe+ (Fig.8)and acid concentration (Fig.9). These results suggest that at the begining of the reaction, only reduction reaction proceed even if oxygen is dissolved.

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The potassium silicate fertilizer produced from fly ash of domestic coal by calcination with potassium carbonate and a small amount of magnesium hydroxide is highly soluble in citric acid but that from the ash of imported coal contains an appreciable amount of insoluble K20. The difference was found to be due not only to the chemical composition but also to the mineral structure of the ash. The imported coal ash w as solubilized by adding domestic coal ash and lime. Major soluble components in the products obtained by the process were K20. Al203.2 Si02, K20. Al203, 2 CaOMg0.2 SiO2, 3 CaOMg0.2 SiO2 and a small amount of an unknown compound, possibly K20. Al203Si02. A considerable amount of glass containing K20 was also formed. The glass was highly soluble when the 0/Si ratio exceeded 3.2.

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Adsorption behavior of Co(II)-nitroso R salt anionic complex (Co NR) on chitin, and a new determination method for ppb levels of Co(II) were studied.
Co(II) is collected as its nitroso R salt(NR) anionic compl ex on chitin at pH range 4.0-7.0, its complex has the composition of Co(II): NR =1: 3. The adsorption isotherm of Co NR on the chitin was known to be fitted by Freundlich equation. The Co NR adsorbed on chitin is eluted with 5 x 10-2 moldm-3 ammonia water, and the absorbance of the eluent was measured at 240.7 nm by atomic absorption spectrophotometry. The calibration curve was linear below Co(II) 8.0 mg/500 cm' (aqueous phase). Relative standard deviations (n=10) of this method were 2.6% for 5 ppb Co(II), 2.4% for 10 ppb Co(II), determination limits (S/11.3) were O.4 ppb for Co(II). For the determination of 5.0 ig of CoaD, the pre sence of diverse ions such as Cd(II), Pb(II), Mn(II), Zn(II) and Bi(III) up to 100 times that of Co(II), and Ni(II) and Cu(II) up to 20 times did not interfere. Interference of Fe(III)with the determination of Co(II) could be masked by adding 10% disodium hydrogenphosphate. The proposed method can be applied to the determination of Co(II) in several water samples.

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Kinetic study of the equimolar reactions of acetic anhydride with various alcohols was investigated under varying dilution of the reactants. The second order reaction rate constants varied according to the change of the initial concentrations of the reactants. The rate constants obtained at an infinite dilution of the reactants were considered to be the real intrinsic rates of alcohol monomers, and varied according to the class of alcohols as follows. The correlations of the rate constants kwwith Taft's substituents constant σ *, and the electron density on the oxygen atom of the alcohol were fairly good in each class of the alkyl substituents of the alcohols. Those correlations show the fact that the electron donating substituents on the alcohols accelerate the esterification reaction, and the in teraction of the oxygen atom of the alcohol with the carbonyl carbon of anhydride plays an important role in this reaction.

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3-Aryl-2-nitroacrylic esters(1) reacted with two molar amounts of TiCl4 in dicholoromethane at 0 ° C to give 3-aryl-3-chloro-2-hydroxyiminoesters(2) in reasonnable yield. The procedure described here may be a general method for the syntheses of the titled compounds 2.

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4, 6-Diamino-2 H-1, 3, 5-thiadiazine-2-thione reacted with amines in DMF at room temperature to form the adduct, N'-substituted (or N', N'-disubstituted)-1\15-dithiocarboxybiguanide (10)(Table 1). Treatment of 10 with alkali produced 1-substituted-4, 6-diamino-1, 3, 5-triazine-2(1 H)-thione ( 2 ) and 4-amino-6-(substituted amino)-1, 3, 5-triazine-2 (1 H)-thione ( 3 )(Table 2). When 10 was heated in boiling water 6-amino-1, 3, 5-triazine-2, 4(1 H, 3 H)dithione (13) and N'-substituted (or N', N'-disubstituted)-biguanide (14) were obtained in addition to 2 and 3 (Table 3). On the other hand, 10 was converted into 1 and 14 by treatment with dilute hydrocholoric acid (Table 4). The structure of 10 was confirmed by IR an d NMR spectral data, and by alternative synthesis from 14 and carbon disulfide. Routs of the reaction of 1 with amines and the reactivities of 10 were also discussed (Figs.2-4).

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For the solid hydrates of α -, β -, and γ -cyclodextrin (CD)s, the partial molar volume (V) of their water of cystallization was determined at 25 ° C by dilatometry as a function of water molar ratio R (=water/CD). The results obtained are as follows.1) For every CD, V increases stepwise at R=1, 2, 5.6, 6.7 (α -CD), R=1, 2, 7.5, 11 (β -CD), and R=6.3, 14 (γ -CD) with increasing R, which gives the existence of 4 kinds of hydrated wate rs. Where, the water at R=1 and 2 for p-CD was first found in this research.2) On measurement, two water molecules located at the center of cavity of a CD molecule can be volumetrically identified and the V of each hydrated water has no dependence on the molecular weight of CD (Mc D) 3) With the 3 rd hydrated water, R(=ca.6) depends little but depends on McD.4) As for the fourth water, both R and V depend on Aim). The hydration states of these water have been discussed by comparing the present results with literature data obtained by X-ray mesurements.

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Inferaction between water soluble diverse, synthetic, polypeptides in aqueous solution was studied by circular dichroism (CD) spectra. The interaction was evaluated from the significant difference between minimum of maximum peaks of CD spectra in ellipticity for mixed solution of two peptides and mean ellipticity of the each peptide. The minimum peak of a mixture for poly(Ala, Pro); A with Poly(Ala, Asp); B, or Poly(Ala, Lys); C, respectively, was less than the mean value of those of A and B or A and C. The minimum peak of polyproline; D with B was less than the mean value of that of D with C. While, the CD pattern of the mixture of poly(Ala, Asp); A, with poly(Gly, Pro); E or poly(Ala, DL-Trp); F, respectively, was accordance with average of those A and E or A and F.

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Nolinear optical properties are investigated for the derivatives of alkanoylamino-a-cyano cinnamates which have asymmetric carbon atoms at their alkyl positions. A new compound, a-cyano-P-(2-phenylpropionylamino)cinnamic acid methyl ester (CPAC-methyl), has been found to be highly effective nonlinear optical material. Both enantiomers of CPAC-methyl (R- and S-isomers) show strong second harmonics (SH) intensity (40 times as that of urea)by powder SH measurement, while racemate was completely SH-inactive. X-Ray diffraction study and the measurement of optical purity have revealed that the crystal structure of CPAC-methyl changes drastically depending upon the ratio of two enantiomers in crystal. CPAC-methyl has rather good transparency at blue light region. The molecular orbital calculation based on MOPAC gave molecular hyperpolarizability β=7.18 x 10-30 ω=0. We also made a rough estimation of nonlinear optical coefficients. b y using oriented gas model. The largest coefficient was 60pm /V.

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We investigated some properties of poly(γ -gluramic acid) newly produced by Bacillus subtilis F-2-01. From the C-NMR spectra of native poly(r-glutamic acid) and its methyl ester obtained by diazomethane treatment, the r-glutamyl structure in poly(r-glutamic acid) was confirmed. The molecular weight was determined with GPC-LALLS (gel permeation chromatography and low angle laser light scattering)method. The diastereoisomer ratio of L- and D-glutamic acids in poly(r-glutamic acid) was evaluated to be 40: 60 with the post-labeling HPLC technique (GITC derivative-method). Other properties were determined (pIC, , , =2.27, [x]= 7.0 (C=1.0, H20)). Free _acid type of poly(r-glutamic acid) was soluble in dimethyl sulfoxide, hot N, N-dimethylformamide and N-methyl-2-pyrrolidone. Thermal decomposition temperature (Td =235.9 °C) and melting ternperaure were determined with TGA and DSC analysis.

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The alginate is an anionic polysaccharide which is composed of 1, 4-linked β -D-mannuronic acid (M) and 1, 4-linked α -L-guluronic acid (G). It is well-known that a sodium alginate aqueous solution forms a gel by introducing divalent metal inos. In the present study, the effect of 114/G ratio on the gelation by Mg2+ ions is investigated by way of rheological and small angle X-ray scattering (SAXS) measurements using a cone-plate type rheometer and a 6 m point focusing SAXS camera, respectively. The guluronic acid rich alginate solution forms the gel at lower concentration of added MgC12 than the mannuronic acid rich alginate. This is because the guluronic acid rich alginate has a higher affinity for Mg2+ than the mannuronic acid rich alginate. SAXS measurements revealed that the gel of the alginate aqueous system has a mass fractal structure at the gel point and the fractal dimension of the structure is 1.45.

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Dialkylphenacylsulfonium salt undergose photoinduced transformation into an ylide form with concomitant release of anion. As this transformation is reversible, we prepared oilsoluble dibuty1(4-methoxyphenacyl)sulfonium percholorate ( 3 ), which in 1, 2-dichloroethane showed an ability to control perchlorate concentration of the aqueous phase in the organic/aqueous tow-phase system by UV-irradiation. Photo-driven active transport of perchlorate through an organic layer by 3 as a carrier was also examined.

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Reaction of carbon dioxide with alcohols and alkyl halides in the presence of potassium carbonate was found to afford unsymmetrical carbonic esters in good yields under mild conditions. The reaction mechanism was also discussed.

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When a mixture of diphenylmethamols and iron(III) chloride (FeC13) was heated in benzene, Friedel-Crafts' diphenylmethylation took place to yield triphenylmethanes with the corresponding benzophenones as by-products. The yield of triphenylmethanes could be eleva ted without a formation of benzophenones by adding a small amount of tribenzylamine to the benzene solution of diphenylmethanols and FeC18. Pentylamine and hydroquinone could be used to get more yield of triphenylmethane in the reaction of benzene with diphenylmethanol. t Synthetic Reaction Using Iron(la) Chloride. V.

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Bond-structure of hydrocarbon and density of polar groups at the surface region of argon and oxygen plasma-treated polyethylene (Ar-PE, 02-PE) were investigated by means of the XPS 1 s and valence band spectra. In case of An-PE, branching and cross-linking hydrocarbo n units occur first, then reaction of radical survived with oxygen and/or nitrogen results in polar groups at the film surface. In case of 02-PE, oxidation of the polymer film is prior to branching and cross-linking.

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Surface modification method of fine magnetite particles by use of silane coupling agents having fluorocarbon chain was investigated. The magnetic fluid (1, 1, 2-trichloro-1, 2, 2trifluoroethane base) was prepared preliminarily by using oleic acid as a surfactant, and then allowed to react with the silane coupling agent. The amount of oleic acid removed from the magnetite surface during the reaction with the coupling agent was measured by the alkaline titration in methanol, and the high exchange rate (>99%) was observed. The modified fine magnetite particles with silane coupling agent could be well dispersed in poly (chlorotrifluoroethene) and produced the fluoro-oil based magnetic fluid.

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The new-type forest decline found in Europe and North America has been ascribed toatmospheric oxidants (Ref. 1-3). Organic hydroperoxides are important oxidants (Ref. 4), andits formations from ozone-natural hydrocarbon reactions were reported. To investigate theformation mechanism as well as to determine atmospheric concentration of hydroperoxides, a technique for efficient collection is necessary. We tested the applicability of mist chamberdeveloped by Cofer et al. (Ref. 7) to the collection of gaseous hydroperoxides. The mistchamber was found to have the advantage in following three points : 1) large flow rate, 2)collection efficiency as high as bubbling, and 3) less H202 production in the trapping solutionduring the sampling of ozone-containing air.

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