By utilizing inclusion complex formation of simple host compounds which had been designed by our idea, separation and optical resolution of a wide variety of organic compounds were achieved effectively. By the same method, water-soluble inorganic and organic compounds were isolated from aqueous solution. Design of some new chiral host compounds was also described.

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An aqueous solution of flavin mononucleotide (FMN) was photostabilized by addition of caffeine and purine bases. However it was destabilized by the addition of pyrimidine bases or p-cyclodextrin, which are generally known to stabilize dyes. Caffeine and purine bases supres s the decoloration of FMN by the formation of a complex with FMN. The fluorescence intensity of FMN decreased by addition of caffeine and purine bases but did not change by addition of pyrimidine bases of β-cyclodextrin. The difference UV spectra of FMN-caffeine complex had a peak at 493nm and this absorption peak was due to the pyrazine ring of FAIN: The quinone moiety of FMN molecule is considered to be covered by caffeine but not to be covered by pyrimidine bases or β-cyclodextrin.

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It is well-known that photoelectrochemical H2 evolution at p-type semiconductors is improved by surface deposition of a noble metal, but its mechanism has not been established clearly. Therefore, we examined the mechanism of photoelectrochemical reduction of proton at Pt deposited p-type indium phosphide photocathode in acidic aqueous electrolyte by measuring its separation factor (S value). This is given by
S= (Ch/Cd)_gas/(Ch/Cd)_soln
where Ch and Cd are the atomic concentration of the isotopes H and D (determined by mass spectroscopy) with respect to the total amount of hydrogen atoms. The deposited Pt was found to be dispersed like islands on the surface (Fig.2). With increase in the amount of Pt deposition, the onset potential for cathodic photocurrent moved to more positive values and the photocurrent increased (Fig.4).
The separation factor measurement is one of the techniques that can be used to estimate the mechanism of hydrogen evolution on the electrode. The S value for Pt-deposited InP corresponded to the one for Pt electrode at high current density (Fig.6). Getting a hint from this S value result, we propose the following mechanism to explain the catalytic effect of Pt island (Fig.7). Under illumination, the photocurrents are concentrated on the deposited Pt islands, so that the potential for the deposited metal is raised, due to this potential shift the photoexcited electrons can pass through the islands to protons. This is quite a new perspective about the electron-transfer mechanism at the interface between a semiconductor coated with metal islands and an electrolyte.

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The stability of Pt catalyst in a phosphoric acid fuel cell was s tudied. The results showed that Pt was lost from the cathode and found in the matrix, and deposited on the anode surface, as shown in Fig.1. This transport of Pt catalyst depended strongly on the potential (Fig.3). The Pt catalyst was quite stable under normal operational voltages (700-600 mV) of the fuel cell, but at OCV Pt was lost quickly from the cathode, resulting in a substantial performance loss (Fig.8). Particle growth was observed in the anode as well as in the cathode (Fig.2). These results indicate that both dissolution-redeposition and migration-coalescence may be involved in the mechanism of Pt particle growth in the cell components. The dissolution rate of Pt catalyst was estimated as functions of potential and temperature, assuming that diffusion of Pt ions in the electrolyte is the rate-determining process (Fig.9). Although the agreement between the calculated and experimental results is not satisfactory (Fig.10), the present results showed the influence of potential and temperature on the stability of Pt catalyst in a phosphoric acid fuel cell.

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The products obtained during hydrolysis processes of Mg(OCH₃)₂ were studied by TEM, XRD, thermal analysis and FT-IR.
When methanol existed in the reaction system, the hydrolysis did not proceed from Mg(OCH₃)₂ to Mg(OH)₂ at 20 and 60°C.
It was observed by TEM that the crystal shapes of resulting Mg(OH)₂ in water were hexagonal plates, while those of resulting Mg(OH)₂ in saturated water vapor were thin films. Crystallite sizes of Mg(OH)2 in water were little affected by the variation of reaction ternperature or of time, the sizes were D₀₀₁=ca.10 nm and D₁₁₀=ca.30 nm. On the other hand, crystallite sizes of Mg(OH)₂ in saturated water vapor varied from 3 to 10 nm in D₀₀₁ and from 15 to 30 nm in D₁₁₀ with increasing reaction temperature and time.
In water, Mg(OH)₂ molecule was once dissolved and changed to crystalline Mg(OH)₂, which was precipitated out of solution. In contrast, in saturated water vapor, a water molecule was incorporated into the interlayer of Mg(OCH₃)₂ and then Mg(OH)₂ was formed by exchanging a methoxyl group for the hydroxyl group due to water.

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Three composites: CF(NiCu)Al, CF(CuNi)Al, and CF(NiCuNi)Al carbon fiber/aluminum were prepared by hot pressing techniques at temperatures of 500°C for 1h ((P-1) method), 500°C for 1.5h ((P-1.5) method), and 670°C for 1h (M-method), and at a constant pressure of 200 kg/cm² (2.03 x 107 Pa).
Carbon fiber was coated by Ni or Cu metal in order to have a good joining with the aluminum matrix.
The maximum tensile strength of CF(NiCu)Al composite prepared by the (P-1) method was about three times as large as that of (NiCu)Al metal composites. Two hot pressing techniques, P- and M-method, were u sed; the former was superior to the latter because it had better joining characteristics. Also, the (P-1) method was superior to the (P-1.5) method.
XPMA study of CF(NiCu)Al composite revealed that about 15-50% of the Al diffused to Cu while only 10% of Cu diffused to Al; 20% of Ni diffused to Cu, while 30% of Cu diffused to Ni. In the case of the CF(CuNi)Al composite, only 5% of Ni diffused to Al and 10%of Al diffused to Ni. The diffusion quantities of Cu and Ni were the same, while only 1% of Cu diffused into carbon fiber.

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The oxidation of ethylene by thallium (III) chloride in aqueous hydrochloric acid solution was investigated at temperatures between 120 and 170°C.
Ethylene was oxidized stoichiometrically with Tl(III) to yield in situ ethylene glycol (EG). The oxidation proceeded by typical successive reaction from ethylene to EG via ethylene chlorohydrin. When the molar ratio of [Cl^-]/[Tl³⁺] in the solution was above 7, EG was formed in 80% yield. The effects of reaction period and temperature on the yield of EG were examined, and the results obtained were plotted contour graphically. The optimum conditions for the preparation of EG were thus determined as follows. The best results will be obtained by running the reaction for 3-5 h at 140-150°C.
The effects of Tl³⁺, H⁺, Cl^- and alkali metal cations on the reaction were also studied, the results suggesting that most of EG was not formed by direct oxidation of ethylene with T1(III) but formed by hydrolysis of ethylene chlorohydrin.

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The reduced copper-catalyzed reactions between a secondary alcohol containing m carbon atoms and a primary alcohol or aldehyde containing n carbon atoms were performed under various conditions to clarify the mechanism of the formation of esters in this reaction. The catalyzed reactions resulted in the formation of esters containing md-n carbon atoms and ketones containing m, 2 m, 3 m, m+n, and 2 n-1 carbon atoms. It was proved that the esters were produced via a hemiacetal intermediate which was formed from the secondary alcohol and the aldehyde. On the other hand, it was found that the ketones containing 2 m, 3 m, and m-Fn carbon atoms were formed by condensation between the ketone produced from the secondary alcohol and the starting alcohol, and the ketone containing 2 n-1 carbon atoms was formed by elimination of carbon monoxide and hydrogen from the hemiacetal intermediate produced from the primary alcohol and the corresponding aldehyde.

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Oxidation of guaiazulene [1] with peracetic acid in acetic acid at 15°C for 3 min gave three major products: Namely, [1K²] (10.0%. isolated yield), a very important key intermediate for novel Intermolecular One-Carbon Transfer in autoxidaition of [1] and its cycloheptatriene isomer [1H₂] (20.0% isolated yield), and the structurally novel biguaiazulenone [1Q₂] (18.0% isolated yield). The reaction also afforded nine separable compounds as minor products (2.0-5.0% isolated yield): Namely, the oxidation product of the side chain [1K₁], guaiazulenequinone [1Q₁], monomeric and dimeric products containing an extranuclear carbon unit ([1L], [1A₂]), biazulene [1B] and 1 H-inden-1-ones ([1C₁], [1E], [1H₂], [1I]), the structures of which were established by the spectroscopic (UV, MS, IR, and NMR) data. Possible reaction pathways are suggested for the formation of these twelve products.

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When a nitroethane solution of iron(III) chloride (FeCl₃) and benzopinacol [1] was allowed to stand at room temperature for 24 h, 1, 2, 2, 2-tetraphenylethanone(benzopinacolone) [7] was given in quantitative yield. The high yield of some benzopinacolones was also found in the reaction of corresponding di-o-tolyl [2] di-m-tolyl [3], di-p-tolyl [5] and di-p-chloro, and tetra-ii-toly1 [6] benzopinacol analogs with FeCl₃ in mild reaction conditions (50°C, 3h), respectively. The reaction seems to proceed in an intramolecular pathway.

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5, 10, 15-Tris (α, α, α-o-pivalamidophenyl) -20-[α-o-[4-[ [12-(1-imidazoly1) dodecyl]carbamoy1]2, 2-dimethylbutanamido]phenyl]porphyrins were synthesized. The long alkyl-chained deriva- tive (n=12) [8] was chemically stable, but the short alkyl-chained derivative (n=3) (10)gradually decomposed on exposure to air and room light in dilute benzene solution. Two reasons were considered to contribute to the stability of the porphyrin [8]: The long distance between the porphyrin ring and the imidazole ring and the preservation of fully delocalization of 18-π electron of the porphyrin system. Conformational structure of the iron(II) complex of [8] was also discussed.

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Monovalent metal salts of 2-hydroxyethyl hydrogen phthalate (HEP) were prepared by the reaction of (HEP) with carbonates of alkali metals such as Li, Na, and K. The curing reactions of the systems of the metal salts, anhydrides, and bisphenol A diglycidyl ether were also investigated. Hexahydrophthalic anhydride (HPA) and maleic anhydride (MA) were used as the anhydrides. Further, some model reactions were conducted by using monovalent metal salts of methyl hydrogen phthalate. In the curing reactions and the model reactions, these metal salts showed catalytic activities which increased with decreasing electronegativities of alkali metals, that is, in the order of Li<Na<K. Therefore, the reactions were presumed to proceed by ionic mechanism. In this case, MA was more reactive than HPA. As for the properties of the cured resins obtained, the effect of introducing ionic linkage appeared clearly in heat distortion temperature and glass transition temperature. Furthermore, for the cured resins based on MA, compressive strength increased by introducing ionic linkage.

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For Hopeite crystals as zinc phosphate films formed on surface pretreated steel sheets of automobile body, EXAFS methods were applied to analyse the local structure of heavy metal components contained in these crystals, and a relationship between these spectral data and the modified crystal structure of Hopeite was discussed.
Analysis was done by observing XANES spe ctra and Fourier transformation of EXAFS for two kinds of powdered Hopeite crystals formed in zinc phosphate solution shown in Table 1.
XANES and EXAFS spectra for Zn-K absorption edge of the HOpeite crystals containing a manganese component were compared with those of the manganese free sample (Figs.2 and 3, Figs.6 and 7). Both spectra showed almost same values of the absorption edge (9.662-.9.663 keV), but the amplitude of XANES and EXAFS spectra for the former was smaller than that for the latter. These facts are explained that the manganese component generated a crystalline strain and the local structure of the crystal was disordered.
Further, XANES and EXAFS spectra for manganese compo nents in Hopeite crystals were investigated (Figs.4 and 8), and compared with those of MnO and MnO₂ as standard sam ples (Figs.5 and 9). Though Mn-K absorption edges were 6.545-4.546 keV for both the modified Hopeite crystals and MnO, that of MnO₂ showed a higher value by 5-6 eV than the former samples. The peak position of EXAFS relating to first neighboring atom showed the same difference as in XANES. These facts suggest that manganese exists as Mn²⁺ in the modified Hopeite crystals. However, the spectra patterns of XANES and EXAFS were different between the modified Hopeite crystals and MnO as oxide.
XANES spectra and Fourier transformation of EXAFS provided a conclusion that the modified Hopeite crystal has a structure of Zn_3-xMn_x(PO₄)₂⋅4H₂0.

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The development of the effect of regeneration retardant added to the “young” viscose at an early stage of ripening has been studied.
Cyclohexylamine (CHA) or polyethy lene glycol (PEG) as regeneration retardant was added to the viscose with various ripening degrees. At some time intervals after the addition of regeneration retardant, the viscose was spun and D-value, swelling degree and load-elongation curve of gel-fiber were measured. Skin-dyed cross section of regenerated fiber was also observed microscopically.
In the case of PEG regeneration retardant effect appeared immediately after its addition to viscose. The effect was not influenced by ripening of viscose, except the very fresh viscose in which content of sulfur by-products was not yet sufficiently high. On the other hand, the effect of CHA increased once with time after its addition to viscose and then decreased. Dithiocarbamates derived from CHA showed a large effect immediately after its addition to viscose and even in the fresh viscose.
Tensile property and skin-dyed cross section of the fiber correspond to the effect of regeneration retardant and it was found that the fiber spun from the relatively young viscose gives the maximum tensile strength.

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Mercury in waste water can be effectively removed by a iron powde r column, but the effluent contains a significant amount of metallic mercury (Hg⁰). Two methods was investigated to reduce the Hg⁰ contents in the effluent. Mercury solution (2-4 mg⋅dm^-3 as Hg²⁺) was passed through a Fe-powder column (∅=6 mm, l=40 mm) packed with a mixture of 1.0 g of Fe-powder (d>100 mesh) and 1.0 g of glass bead (d=0.18-0.25 mm) by up-flow method. The Hg⁰ concentration in the effluent was reduced by the addition of CuSO₄ to the influent (Method I) or by connecting a Hg⁰-adsorbing column to the top of the Fe-powder column (Tables 1, 2). In particular, the Fe-powder column pretreated with CuSO₄ solution was effective for the removal of Hg⁰ (Method II) (Table 2). Removal of mercury by the both methods (I, II) were affected by the pH of the influent (Fig.1). At pH 2.5, Hg⁰ concentrations in the effluent were less than 2 tigdm-3 (Method I ) and 0.2. pgdm-3 (Method II) when 7 dm³ of mercury (II) solution was treated. Under the same conditions, Hg(II) concentrations were less. than O.5μg. dm³ and little copper was detected (Figs.2, 3). In the presence of w eak ligands, total mercury concentrations in the effluent were reduce to less than 2.2 μg. dm³ (Table 3). However, in the presence of strong ligands such as EDTA, peptone and KI, the removal rate was decreased (Table 3). From these results, it is concluded that these two methods using copper are simple and useful for the removal of mercury in laboratory waste water.

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Measurement of adsorption coefficient of a chemical to soil does not always give a definite value because of the variety of composition and property of soil. Attempts to find proper soil substituts for the measurement of adsorption coefficient have been made by using some adsorbents, such as cellulose, humic acid, florisil, silica gel, kaolin, and silicic acid. The comparison of k_OC (adsorption coefficient normalized by organic carbon content (C_OC) of the sample), of γ-BHC for these adsorbents was made with k_OC of soil samples of C_OC betwe en 0.253 and 10.4 %. Among these adsorbents, humic acid, which is one of major com ponents of soil, gave close values of k_OC to those of soil. Five kinds of alicyclic compounds and aromatic compounds, such as dieldrin, o-dichlorobenzene etc., also gave similar values of k_OC to those of soil for γ-BHC. However, 3, 4-dichloroaniline gave a different value of k_OC with humic acid from that with soil, probably because of the polarity of the molecules. Based on these experimental results, we concluded that humic acid could be used instead of soil for the measurement of the k_OC of nonpolar halogenated alicyclic and aromatic compounds.

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Basic experiments for seeking the parent combustion materials of soot were carried out by use of trace amounts of soot produced from eight kinds of aromatic hydrocarbon benzene, toluene, o-, m-, p-xylene and styrene(I), ethylbenzene and cumene. The ingredients in the soot were determined by curie point pyrolysis gas chromatography, the pyrolysis ternperature being 358°C.
The parent m aterial was shown as the main peak in the gas chromatograph of the corresponding soot produced from(I), ethylbenzene was appeared as a weak peak in the gas chromatograph of the soot of ethylbenzene, and no detectable peak of cumene was seen for the soot produced by cumene.
The polycyclic compounds such as naphthalene and anthracene were detected in all soots. Oxygen containing compounds such as cresol and xylenol were also detected. The oxygen containing compounds were related structurally with the parent hydrocarbon of the soot. It was found that the soot produced from the combustion of the eight kinds of aromatic hydrocarbon can be identified by the detection of both characteristic contents of the hydrocarbon and the oxygen containing derivatives.

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A hydrogen-isotope exchange reaction between each of six monohydrogenphosphates and tritiated water vapor has been observed at 50-80°C. Following results were obtained after the activities observed in the solid samples were analyzed by using A′′-McKay and Arrhenius plots. 1. It is possible to compare the acidity of monohydrogenphosphates with each 9ther. 2. The acidity increases with increasing temperature. 3. Both the acidity of the compound and the temperature dependence of its reactivity increase when the electronegativity of a metal element in monohydrogenphosphate becomes large.

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The chromophore of ZnTMPyP(3) (TMPyP(n), 5, 10, 15, 20-tetrakis(1-methyl-2-, 3-, and 4-pyridinio)porphyrin) was hardly photobleached while those of ZnTMPyP(2) and ZnTMPyP(4) were photobleached in an aqueous solution containing ethylenediaminetetraacetic acid at pH 6.8. For the photoreduction of methylviologen, ZnTMPyP(3) was the most effective sensitizer among the three structural isomers.

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Zeolite-supported inorganic nucleophilic reagents were prepared by impregnation with their aqueous solutions, followed by calcination, and applied to several liquid-phase organic reactions. The reaction between alkyl bromides and potassium chromate was promoted by zeolites to give aldehydes, although residual water adsorbed on the zeolites caused unfavorable hydrolysis reaction to give alcohols. Zeolites also accelerated the oxidation of alcohols with potassium dichromate and displacement reactions of alkyl bromides with alkali iodides. The product yields were dependent on the type of the zeolites and counter cations of the inorganic nucleophiles.

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Three zirconium(IV)-oxalato compounds were obtained as powders by mixing an aqueous solution of ZrOCl₂⋅8H₂O with an aqueous solution of K₃[Cr(OX)₃]⋅3H₂O, K₃[(Fe(OX)₃]⋅3H₂O or K₃[Co(OX)₃]₃⋅H₂O. These compounds were found to have the compositions of (ZrO)₁₁(OX)₁₀(OH)₂(H₂O)₅₀ ([Zr-Cr]), (ZrO)₁₁(OX)₁₀(OH)₂(H₂O)₄₀ ([Zr-Fe]) and (ZrO)₁₁CO(OX)₁₀(OH)₄(H₂O)₅₀ ([Zr-Co]), respectively. Traces of chromium or iron were contained in [ZrCr] or [Cr-Fe]. The Zr/M atomic ratios (M=Cr or Fe) were about 600 or 100, respectively, whereas the corresponding ratio was 11 for [Zr-Co]. Thermal analyses revealed that all of these compounds were almost completely dehydrated in the temperature range of 200 to 300°C and gave their oxides by further heating to about 600°C. It was also found that, in the range of 350-450°C, [Zr-Cr] and [Zr-Fe] formed intermediates which had the compositions of (ZrO) (C08)₅(ZrO₂)₆ and (ZrO)₈(CO₃)₃(ZrO₂)₈.

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In order to isolate the diastereoisomers (abbreviated as isomers below) in [Co(adao)(L-phe)]⁺(adao: ^-OOCCH₂NH₂(CH₂)₂NH(CH₂)₂NH₂; L-phe: C₆H₅CH₂CH(NH₂)C00^-) and to clarify their structures, the liquid chromatographic separation was carried out on the reaction products from β-mer(N)-[Co(adao)Cl(H₂O)]ClO₄ and L-phenylalaninate ion. Two isomers were successfully isolated as the crystals from two eluates (EI and EII). The elemental analyses indicated that the crystals had the compositions of [Co(adao)(L-phe)]X⋅nH₂O { (X, n) = (I, 2), (ClO₄, 1)}, respectively. Their absorption spectra in aqueous solution showed that both crystals are trans(O) isomers. As shown in Fig., 1, it is apparent that adao in the trans(O)isomers coordinates with the β-mer(N) coordination mode. By using the circular dichroism (CD) spectra of two isomers, the configurational effective CD curves and the vicinal effective CD curve of L-phenylalanine were calculated. On the basis of the configurational CD curve for the trans(O) isomer from EI, it has been deduced that this isomer has the Δ(ΔΔΔΔ)-β-mer(N)-trans(O) structure. Therefore, the isomer from Elf has been assigned to the Δ(ΔΔΔΔ)-β-mer(N)-trans(O) one.

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Various kinds of organic phosphorus compounds in aqueous solution were photochemically decomposed by ultraviolet irradiation and the phosphate ion produced was determined by ion chromatography. Hydrogen peroxide was added to the sample solution, which was prepared by adding methanol solution of phosphorus compounds to water. The mixture was, then, irradiated for 30-90 min under bubbling of O₂ gas. It took 30 min to decompose quantitatively most of phosphorus compounds When a sample contained halogen and/or sulfur, proposed photochemical decomposition-ion chromatography method makes it possible to determine these elements simulteneously as X^-, SO₄^2- and PO₄^3-.

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Some Trichoptera, so-called net spinning caddis, eject the contents of their silkglands to build a nest for protecting themselves in a rapid stream. The adhesive protein formed by caddis worm Stenopsyche griseipennis McLachlan has been studied to obtain some basic knowledges such as the preparation of fibroin solution, the amino acid analysis, and the bonding strengths on test pieces. The protein was found to have the tensile strengths of the highest 14 kg/cm² on iron and 7 kg/cm² on pig bone, and the highest compressive shear strength 12kg/cm² on iron.
A discuss ion is presented that includes results of the bonding strengths of Bombyx mori fibroin.

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A new instrument for automatic horizontal lifting deposition of LB films has been developed, and was applied to depositing high quality LB films of lanthanum stearate. The long spacing of the LB films deposited by this method showed almost no dependence on the pH of the subphase solutions.

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