Photovoltaic properties of MIM(metal-insulator-metal) type cells fabricated by copper(Cu), poly(p-phenylene sulfide) (PPS) and aluminum (Al) were studied. It is possible to evaporate PPS on a substrate by heating it at temperature above 350°C. The thickness of evaporated films, in the range from 500 to 1500Å, was controlled by the evaporation time and temperature. The MIM cells thus obtained showed a rectification effect in the dark as well as a photovoltaic effect under the illumination of light. The power conversion efficiency obtained was 0.12% for monochromatic light at 300 nm. These behaviors are explained by the formation of Schottky barrier on the surface between Al and PPS. In order to characterize the barrier states, the capacitance of the cell under various bias fields was measured by using a low frequency oscillographic method, and the 1/C² vs. V plots showed a linear relation, which implies the presence of the depletion layer.

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A series of investigations of amorphous silicon solar cells (Ag/ITO/nip a-Si: H) on polymer film substrates has been conducted. This paper reports the relationship between the properties of ITO (In-Sn oxide) layer and the cell characteristics.
The ITO layer was formed on a-Si layer by the reactive vacuum deposition with the electron beam (EB-ITO) or the reactive sputtering (SP-ITO). When n-layer is a microcrystallized layer, the conversion efficiency of, the cell with SP-ITO is approximately 1.1 times higher than that with EB-ITO. On the other hand, when n-layer is an amorphous layer, the cell characteristics are almost the same in both cases.
EB-ITO and SP-ITO layers show almost the same characteristics on the absorption coefficient and the electrical resistance. However, SEM photographs and X-ray diffraction patterns showed that EB-ITO had granular-columnar structure and larger crystal size compared with SP-ITO. These differences probably affect on the structural and electrical properties of the Ag/ITO and ITO/Si interfaces, . In fact the contact resistance on Ag/EB-ITO was found to be greater than that on Ag/SP-ITO.

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Thin films of amorphous ABOa-type ferroelectric materials (PbTiO₃ and LiNbO₃) are prepared by RF-sputtering on cooled substrates and their structure and electrical properties are studied. In as-sputtered PbTiO3 films, there are Pb crystallites and these films exhibit a high surface electrical conductivity of-10 (Ω·. cm)^-1. This high electrical conductivity is attributed to hopping of electrons between the Pb crystallites. When the as-sputtered films are annealed above 220°C, the surface electrical conductivity is reduced. The annealing causes a decrease in Pb crystallites in the film. This annealed film resembles roller-quenched amorphous PbTiO3. When the films are annealed above 500°C, they become Polycrystalline PbTiO3 films. As-sputtered LiNbO₃ film resembles roller-quenched amorphous LiNbO₃. They exhibit similar temperature dependence of the dielectic constants. Amorphous LiNbO₃ films exhibit high dielectric constants in film is based between the nealed above the high temperature and low measuring frequency region. Amorphous on an O-octahedral structure. The transfer of the Li atoms through O-octahedras may cause the high dielectric constant. When the films 550°C, they become polycrystalline LiNbO₃ films. LiNbO₃ openings are an nealed above 550°C, they become polycrystalline LiNbO₃ films.

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Application of ion implantation to the modification of electrochemical properties of metal surfaces is briefly reviewed. The ion implantations of Ark, N₂⁺, O₂⁺, Zn⁺, Cu⁺, Ni⁺, Cr⁺, Ti⁺, and Si⁺ into substrates were carried out by means of a RIKEN 200 kV Ion Implanter. Concentration-depth profiles of the implanted element were measured by a secondary ion mass spectrometry (SIMS). The electrochemical properties of the ion implanted specimens were studied by means of multi-sweep cyclic voltammetry. A 0.5 mol·dm^-3 sodium acetate buffer (pH 5) solution was utilized as a mild corrosion atmosphere. The relationship between the composition of the surface layer and electrochemical dissolution properties was discussed. The anodic dissolution of the iron electrodes was remarkably suppressed by the ion implantation of Cr, Si, and Ti with a dose of 1× 10¹⁷ ions cm^-2. The concentration-depth profiles and the cyclic voltammograms were measured for Ni⁺-Cr⁺and Cr⁺-O₂⁺double-implanted iron specimens. Oxidation of chromium by the additional O2⁺-implantation depressed the anodic dissolution of the Cr-implanted iron electrode. These results suggest that the ion implantation is effective in making a corrosion inhibited surface layer on iron.

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Perpendicular magnetic recording media by means of electroless plating method were studied and developed. A plating bath A composed of ammoniacal malonate-malate complexing agents was initially developed by deciding the optimum conditions according to the effects of three main factors: concentrations of MnSO₄ and NiSO₄, and pH of the bath on the magnetic properties and crystal structure of the Co alloy-thin films obtained. Secondly, the bath composition was further optimized for CoSO₄ concentration, NaH2PO₂ concentration and bath temperature to obtain the revised bath B. The magnetic film plated from the bath B showed the lower coercivity Hc (_??_) and hence may be applied with the head having the narrower gap length for achieving the higher recording density. The films plated from the baths A and B were both composed of columnar structure of hcp crystal with 0.05 μm diameter. It was observed that the grains were highly-oriented with a narrow dispersion of c-axis orientation normal to surface plane according to the rocking curve method. As a result of preparation of disks plated from baths A and B, the di-pulse waveforms which are characteristic of the perpendicular recording were observed at low bit recording density. The recording densities of D₅₀=18500 FRPI and 25000 FRPI were obtained respectively for the disks when used with the ring-type head and the improved ring head having the narrower gap length. M

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Photocrosslinkable unsaturated polyester resin was synthesized by the condensation reaction. The synthesized polyester shows a photosensitivity only in ultraviolet region. For the purpose of argon ion laser recording at 488 nm and 514.5 nm as the main wavelengths, spectral sensitization of this polymer with several sensitizers was investigated. By adding spectral sensitizers such as N-phenyl-9 (10 H)-acridinethione, pyrylium and thiopyrylium compounds, the range of the spectral sensitivity was extended toward longer wavelengths. The characteristics to laser exposure were evaluated under both static and dynamic conditions. Among the photopolymer systems studied, the photopolymer sensitized with 4-(4-butoxyphenyl)-2, 6diphenylthiopyrylium perchlorate showed a very high sensitivity, 14 mJ/cm² for 488 nm laser exposure, under static conditions. Under the dynamic conditions such as scanning exposure system, a reciprocity law failure appeared in the very short exposure time region of the order of 10^-6 s. However, a diazo-type photopolymer, in which direct excitation of diazonio group was induced, was found to follow the reciprocity law. Therefore, the main reason of reciprocity law failure observed in spectral sensitized polymer system was due to the energy transfer process from the sensitizer in triplet state to the polyester.

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In an attempt to make a new type of artificial cell that has enzymatic activity on the cell surface, polyamide microcapsules having many carboxyl groups in their membrane were prepared using an interfacial polymerization technique, and trypsin was covalently bound directly or via a spacer to their surface. The enzymatic activity of the immobilized trypsin was measured and compared with that of intact trypsin in solution.
When N^α-benzoyl-DL-argininep-p-nitroanilide, a low-molecular-weight substrate, was used, specific activity was appreciably higher for trypsin in the immobilized state than in solution. On the other hand, with casein, a high-molecular-weight substrate, trypsin immobilized without a spacer showed specific activity only a half as high as trypsin bound to the microcapsule surface via a spacer probably because of steric hindrance. The activity of both f orms of the immobilized trypsin was much lower than that of free trypsin. Immobilization caused a slight shift of optimum pH for enzymatic activity of trypsin to the alkaline side because the hydrogen ion concentration was higher on the microcapsule surface than in the bulk due to negative charges of the dissociated surface carboxyl groups (Figs.1 and 2). Both Michaelis constant, K_m, and maximum reaction velocity, Vmax, were found considerably higher for free trypsin in solution than for the immobilized enzyme (Table 2). Thermal stability of the enzyme was remarkably increased by immobilization to the microcapsule surface (Fig.5).

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Effect of mechanochemical contraction of a crosslinked poly(methacrylic acid) (PMAA)membrane on the water permeability was studied by forming complexes with poly (ethylene glycol) (PEG), poly(Nvinylpyrrolidone) (PVP), poly(methyl vinyl ether) (PMVE) and poly(vinyl alcohol) (PVA). It was found that PEG and its derivatives increase water permeability of the membrane, however, PVP and PMVE rather prevented the water permation. From the experimental results of the membrane contraction as well as water permeability, it was assumed that a penetration of the polymer through the micropores of the membrane plays an essential role for the increased water permeation, and that the polymer is required to have certain structure so as to make the successful penetration. This expanding and shrinking behaviors of the micropores of PMAA membrane was applied to control the diffusional velocity of substrate (saccharose) in order to control the enzyme (invertase) reaction. It was also found that the apparent release rate of raffinose entrapped in the crosslinked PMAA gel is also changed by the mechanochemical reaction of the gel.

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Protein A, a cell wall polypeptide (MW=42000) elaborated by many strains of Staphylococcus aureus, binds the Fc portion of certain types of immunoglobulin G (IgG). Protein A-bearing St. aureus cells completely retain the binding properties of protein A. Because of the convenient handling of bacteria, staphylococci-bearing protein A was covalently attached to a polymer membrane. The present study demonstrated that the Staphyrococcus aureus cell-bound polymer membrane is capable of recognizing specifically IgG.
The membrane was then coupled with a Clark-type oxygen electrode to construct the biosensing system for IgG molecules in a solution. Catalase-labeled IgG was put in competition with IgG to be determined against the polymer membrane-bound staphylococci. The catalaselabeled IgG complexed on the membrane was assayed for enzyme activity to decompose H₂O₂to O2 with the oxygen electrode. IgG was determined in the concentration ranging from lx 10^-7 to 1 x10^-5 g·ml^-1. The Staphylococcus aureus-bound membrane seems feasible in recognizing and sensing a trace amount of IgG in a solution.

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A micro enzyme FET for sensing urea has been developed using semiconductor and enzymeimmobilizing technologies. The enzyme FET was composed of an ISFET (Ion Sensitive Field Effect Transistor) which had been developed as a pH sensor and of the urease-immobilized membrane in which urease was immobilized on the cellulose membrane by the cross-linking method with glutaraldehyde. As pH in the solution was changed by the urea-urease reaction, the pH change depending on the concentration of urea was detected by the ISFET. The measurement of urea in the solution was carried out using the differential mode between the enzyme FET and a reference FET on which urease was not immobilized. It was found that the differential mode of measurement automatically compensated the temperature and ambient pH changes in the solution and stable responses to the various concentrations of urea were obtained. By the use of the calibration curve obtained by the present sensor, it was possible to determine the urea concentration in the range 5 X 10-5-1x 10-2 g/ml. The response time of the enzyme FET was about 1 minute, and was considered to be limited by both urea-urease reaction rate and OH- diffusion time through the cellulose membrane. The life time of the present sensor was 28 days with the data fluctuation within ±3 mV at the output level of 20mV, depending on the activity of the immobilized urease. The performance characteristics of the present enzyme FET were similar to those reported previously using conventional urea sensors without ISFETs. Some advantages can be emphasized for enzyme FETs; i. e., miniaturization and multifunctioning are possible using the integrated circuit technology. Utilizing those advantages, various types of FET biosensors will be developed and applied for clinical uses.

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Plasma-initiated graft polymerization of water-soluble vinyl monomers was carried out onto polyethylene, polypropylene and poly(ethylene terephthalate) films. It was found that acrylic acid, 2-hydroxyethyl methacrylate and acrylamide could be easily graft-polymerized from 0.5to 670% of the weight of dry films depending on the conditions of plasma-exposure and postpolymerization time No 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) or 2-dimethylaminoethyl methacrylate were susceptible to graft-polymerization themselves, but successfully graft-copolymerized with acrylic acid and acrylamide. Graft films obtained showed significant decrease in contact angle of water.
It was found that PE films to which acrylic acid and acrylic acid-AMPS were graft-polymerized could adsorb such metal ions as Cu²⁺, Co²⁺ and Cr³⁺, and the amounts of adsorbed ions were determind. It was also found that the metal ions adsorbed to poly(ethylene) film could be desorbed reversibly by immersing the film in HCl solution.

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In order to elucidate the gas permeation mechanism of the polymer/liquid crystal composite membrane, N-(4-ethoxybenzylidene)-4-butylaniline 1(EBBA) was. blended into polycarbonate (PC) with 1, 2-dichloroethane and for the prepared' composite membrane the relationships between the membrane structure and the gas permeation were investigated. On the basis of DSC, X-ray diffraction, sorption isotherm, sorption-desorption studies and scanning electron microscopic observation, the aggregated state of the polymer/liquid crystal composite membrane was defined as follows; EBBA molecules in the composite membrane exist in an almost molecularly dispersed state up to EBBA fraction of 30 wt%, and in the case of EBBA fraction above 30 wt% EBBA molecules form a domain as the mutual continuous phase among the threedimensional network of polycarbonate fibrils. The composite membrane containing EBBA of 60 wt% can be handled as a homogeneous medium in a temperature range above the crystalliquid crystal phase transition temperature.
The permeability coefficient, P for hydrocarbon gases through the 60 wt% EBBA composite membrane increases 100-200 times over several degrees in the phase transition temperature range. P for hydrocarbon gases decreases with increasing number of carbon atoms below the phase transition temperature, while P increases with increasing number of carbon atoms above it. These permeation mechanisms were well confirmed by using PC-laminated membrane. The permeation process is predominantly controlled by diffusion mechanism below the transition temperature of EBBA, while. the solubility factor significantly affects gas permeation above it. Consequently, the solubility- and diffusion-controlling factors of liquid crystalline materials are applicable to the molecular design of an oxygen enrichment membrane. PC/butyl 4- (4ethoxyphenoxycarbonyl) phenyl carbonate(BEPCPC, 60 wt%) composite membrane exhibited the excellent oxygen permeability (P_O2=2.25×10^-9cm³(STP)·cm^-1·S^-1cmHg^-1) and the permselectivity (P_O2/P_N2/=2.81) at 333 K just above the crystal-liquid crystal phase transition temperature.

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Immobilized liquid polyethylene glycol (PEG) membranes dissolving metal salts were investigated to clarify their abilities for permeation of gases (N₂, O₂, and CO₂), since the interaction of the gas molecules with the metal ions incorporated into PEG or nearly naked counter anions might cause enhanced transportation of the gases. The permeability for CO, was almost unchanged or slightly increased whereas those for, N, and O₂ were decreased by adding the salts, resulting in a considerable augmentation in the permselectivity for CO, (Table 1). This enhancement was found to arise chiefly from increase in CO₂ sorbability upon addition of the salts. The equilibrium isotherm for CO₂ in PEG containing the salt exhibited a typical dual mode type consisting of the Henry's law dissolution and the Langmuir type sorption (Fig.3). The parameters for the latter uptake showed good correlation with the pK, values of the conjugate acids of anions (Fig.5), suggesting this uptake to be caused by the acid base interaction between a CO₂ molecule and the naked anion induced through PEG coordination to the metal cation. The augmentation of CO₂ permselectivity was more significant for alkaline earth metal salts than alkali metal ones (Table 3). Such differences in the salt effect could be attributed to change of extents of anion activation in PEG between alkali and alkaline earth metal salts. The salt effect enhancing the CO₂ permselectivity was most remarkable for Na ⁺ and Ca²⁺ salts, respectively, among the alkali and alkaline earth metal salts employed here, demonstrating these effect to depend on the size of metal cations (Fig.7).

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The transport rate has been measured f or amino acids coupled to a flow of hexafluorophosphate or perchlorate ions across supported liquid membranes. A microporous polypropylene film was used as the support. The liquid membrane consisted of trialkyl phosphate and hydrophobic organic liquid such as p-nitrophenyl heptyl ether (NPHE), o-nitrophenyl phenyl ether, 1, 5-dichloropentane and diphenyl ether. The trialkyl phosphate was used as a carrier of amino acids across the membrane. In the several kinds of trialkyl phosphates, only tributyl and tripentyl phosphates actually acted as carriers of lipophilic amino acids such as phenylalanine, leucine, isoleucine, phenylglycine, valine and methionine. For the membrane systems used, alkali metal and hydrogen ions were transported in the same direction as amino acids and hexafluorophosphate or perchlorate ions. The cations and anions transported across the membrane were equal in number of molecules. For the liquid membrane containing tripentyl phosphate, the flux of leucine across the membrane increased linearly with the carrier concentration in the range O.6-2.5 moldm-3. The transport of leucine was scarcely observed at the carrier concentrations below 0.3 mol dm-3. A rise in stability of the membrane resulted in a lowering of the flux of leucine.

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A homogeneous membrane which is mainly conformed in an a-helical structure was obtained from a copolymer of L-leucine and γ-benzyl L-glutamate (copoly(LL-BLG)), an apparent mole ratio of 2: 1. The permeability of gases through this membrane, as can be expected from much more composition of L-leucine residue, was very large compared with poly(γ-benzyl L-glutamate) (PBLG). The copoly(LL-BLG) membrane is quite hydrophobic from the view point of oxygen permeability. In other words no effect of water to the oxygen permeability was found. Taking the advantage of the chemically inert isobutyl group of copoly(LL-BLG), only γ-benzyl L-glutamate residue was reacted into N-(3-hydroxypropy1)glutamine residue by 3-amino-1-propanol or r-glutamic acid residue by a mixed solution of 1 mol/l NaOH and methanol. The membranes thus obtained became highly water-swallen. Copoly(LL-HPG) membrane with N'-(3-hydroxypropyl)glutamine residue contains water about 230% and copoly(LL-GA) membrane with glutamic acid residue contains water about 690%. The oxygen permeability through these membranes was extremely high and similar to that through cornea.
The transport properties of NaCl, KCl, urea, creatinine and uric acid for copoly(LL-HPG)and copoly(LL-GA) membranes were determined. Except for uric acid, the permeability coefficients and diffusion coefficients depended on the water content. The small permeability of uric acid through copoly(LL-HPG) membrane was attributable to the extremely small diffusivity.

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The characterization of poly(amino acid) membranes, of which the transport properties are changeable by the variation of the physical state of the membranes, was studied.
α-Helix to random coil transition of crosslinked poly(glutamic acid) (PGA) membrane was confirmed by IR and the membrane length variation studies. The filtration coefficient, Lp, and the permeability coefficient of sucrose, ω₅, of PGA gradually increased with increasing solution pH below pH 5.0, but steeply increased above pFI 5. O. On the other hand, the ionic salt permeability of KCI, ω₁, decreased when pH was increased to 5.0 and markedly increased on further increasing of pH. The values of ω₅ and L_p in turn were reduced to the frictions, f_wm(water-membrane), f_2m (co-ion-membrane) and f_2w (co-ion-water); there was a direct correlation between the behavior of these frictions and the physical state of the membrane. The cross-membrane ionic conductance measurements were made by using poly-. (L-cysteine) (PLCys) inter-polymer membranes. As a result, it was confirmed that the equivalent ionic conductance of KCI, A_KCl, was strongly dependent on the oxidation reaction in bathing solution. The dperease of A_KCl was due to the effect of crosslinking reaction between side chain -SH groups. These results showed that the transport properties of these poly(amino acid) membranes may be regulated by pH induced phase transition and reaction controlled polymer conformational change in membrane phase.

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Membranes having pyridine moieties as fixed carriers for anion transport were mede from copolymers of styrene(St) and vinylpyridine monomers such as 4-vinylpyridine(4 VPy), 3vinylpyridine(3 VPy), 2-methyl-5-vinylpyridine(2 M 5 VPy), or 2-vinylpyridine(2 VPy).
Anions were transported through these membranes against its concentration gradient, that is, the active transport of anions was observed. These membranes showed a high selectivity for the transport of anions, namely, the membrane of 4 VPy-St copolymer could transport bromide ion, while it didn't transport chloride ion. On the other hand, the membrane of 2 VPy-St copolymer could transport only chloride ion with rejection of bromide ion. This high selectivity is given by the affinity between the carrier and anion, i. e., the incorporation of anions into the membrane.

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An alternating copolymer of maleic anhydride and 2-methyl-2-propen-1-ol [Poly(MAn-altMAA)] was prepared and the alternative arrangement of carboxyl and 1, 5-lactone units were mainly found in the copolymer. In order to evaluate a function of vicinal carboxyl and lactone moieties in the active transport of alkali metal cations, Poly (MAn-alt-MAA)poly(acrylonitrile) (3: 7 by weight) blended membranes were prepared by casting from N, Ndimethylformamide solution.
By using a diaphram cell, two pairs of alkali cations, K⁺-Na⁺ and Na⁺-Li, were actively trasnported through the membrane from alkaline to acidic solution (Fig.3 and 4). Transport behaviors, such as maximum transport ratio, transport rate and transport selectivity, were evaluated by varying the membrane thickness (20-60μm) and the initial concentration of cell solution (0.08-0.8 mol·dm³). The maximum transport value was high, e. g.88% for K⁺, at the low initial concentration, and it decreased with the initial concentration. The transport rate was approximately proportional to the initial concentration and inversely proportional to the membrane thickness. It is interesting that the transport rate of Na ⁺ was changed in the presence of the other alkali metal ion. The transport selectivity was slightly affected by the membrane thickness and it decreased somewhat with the initial concentration. The average transport selectivities of K⁺/Na⁺ and Na⁺/Li⁺ were 1.8 and 1.9, respectively (Table 2, Figs.5and 6). The transport mechanism was discussed and the apparent diffusion coefficient was calculated. Scanning electron micrographs (SEM) showed that the membrane was consisted of three layers, i. e. dense layer, central layer and porous layer (air side in preparation). The remarkable change in morphology of the used membrane at the high initial concentration was observed (Fig.7).

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It is wellknown that an ion flux is proportional to the difference of electrochemical potential between the ionic solutions which are separated by a simple physicochemical membrane. In this paper, the reverse ion transport coupled to chemical reaction was studied to explain the transport phenomena in terms of the membrane equation reported in the previous literatures.
The liquid membrane was prepared by dissolving 10^-2mol·dm^-3 octadecylamine hydrochloride in I-octanol, and it was supported into a membrane filter. This liquid anion exchange membrane showed an ideal potential response for Cl and OH^- (Fig.2). The system, (HClsoln. )-(liquid membrane)-(NaCH-NaOH soln. ) having the same Cl- concentrations in two aqueous phases, was chosen as the reverse transPort system. The ion flux and membrane potential of the system were measured as a function of time (Fig.3 and 5). The reverse transport of Cl^- driven by an acid-base reaction as well as the change in membrane potential were observed (Table 1).
Based on an assumption that acid-base reaction takes place very fast, the experimental results were reasonably explained according to our equations (Table 2). It was concluded that the acid-base reaction energy is transformed into the electrochemical potential and as a result, the reverse ion flux is driven by the difference in the electrochemical potential of Clbetween phases I and II.

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Interactions of ions with polyamine and polyether ligands at the surface of the synthetic bilayer membranes were studied. The gel filtration experiments showed nearly 100% trapping of some sodium aromatic sulfonates by a polyether-type membrane (Fig.3). Fluorescence spectroscopic measurements suggested the interaction between sodium ion and the polyether ligands (Fig.4). Fig.5 shows a model for the interaction. As a result of the mixing between the double-chain ammonium membrane and the azobenzene membrane containing polyamine ligands, the absorption maximum of the azobenzene chromophore shifted from 320 to 355 nm (Fig.6). The rate of mixing was accelerated 30 times by addition of 10^-3 mol/l HCl. The acceleration effect was also observed upon addition of 10^-2 mol/l KCl. On the contrary, the rate decreased by Cu²⁺ ions. The results are shown in Table 1 and Fig.7. Fluorescence intensity of a biphenyl membrane which has polyamine ligands was enhanced by HC1 and quenched by Cu²⁺ ion (Table 2). In mixed membranes with a double-chain ammonium salt, the fluorescence intensity decreased due to phase separation induced by sulfate ions. Fig.9shows the experimental data and Fig.10 is a schematic illustration of the ion-induced phase separation.

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The reactive and binding specificities have been obtained for acyl transfer reaction of pnitrophenyl decanoate (S₁₀) with 2-hexyldecanehydroxamic acid (HDHA) in the bilayer system (didodecyldimethylammonium bromide: 2C₁₂N2C₁). They are attributed to the stronger hydrophobic, interaction between the substrate (S₁₀) and the mixed nucleophile (HDHA+2C₁₂N2C₁).
In the stereoselective hydrolysis of p-nitrophenyl N-decanoyl-D(L)-phenylalaninate (D-, L-S₁₀)and p-nitrophenyl N-hexadecanoyl-D(L)-phenylalaninate (D-, L-S₁₆), the liquid crystalline bilayer systems of N-palmitoyl-L-histidine (PalHis) and double-chain surfactants (2C₁₄N2C₁and C₁₄N2C₁, [ditetradecyldimethylammonium bromide]) offered the relatively higher enantiomer rate ratios as compared with those obtained in the crystalline bilayer system of PAU-lis and dioctadecyldimethylammoniunm bromide (2C₁₈N2C₁) and the comicellar system of PalHis and octadecyltrimethylammonium chloride (OTAC). Furthermore, the acyl transfer rate of D(L)-S₁₀ possessing an appropriately long N-acyl chain was found to be largest in both of the bilayer and micellar systems. The notable aspects of the present reaction are also reflected Kb in the kinetic parameters (A+S_n ⇔K_bAS_n→kp;A, AS_n, and P stand for an aggregate composed of nucleophilie and surfactant, an aggregate-substrate cOmplex, and p-nitrophenol, respectively). Although the difference in the microenvironment of the bilayer (PalHis+2C_mN2C₁ [m=12, 18]) and the spherical micellar (PalHis+OTAC) systems offered a different relative order of the binding efficiency (K_b) between the L- and D-enantiorners, the Kb values of the long-chain substrate (D(L)-S₁₀) were fairly large as compared with those of the shortchain substrate (D(L)-S₂ [p-nitrophenyl N-acetyl-D(L)-phenylalaninate]) in all the reaction systems.

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Differences were examined in two-dimensional fluidity between monolayers composed of N, N'-disubstituted dithiooxamides on pure water and that on an aqueous copper (II) sulfate. solution. The rotating cylinder method with licopodium powder developed by H. E. Ries Jr., was employed. On pure water a surface flow pattern was observed which was suggestive of a macroscopic slip in the monolayer similar to that in a three-dimensional crystal (refer Fig.3-a). This might mean that the monolayer are in a pseudo-crystalline state with. a longrange order and a rather weaker molecular interaction. On an aqueous copper (II) sulfate solution, the licopodium powder lines drew smoothly curved lines without break, as if they were on a stretched expandable rubber film. This suggests that the molecules composing the monolayer are combined each other through coordination bonds to copper ions, that is, the intermolecular force is rather strong and results in a' short-range order (refer Fig.3-b). These techniques of direct observation of fluidity, plasticity, and viscoelasticity are widely applicable and useful for process control of manufactureing the multilayer films.

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The membrane potential generated by a transmembrane photoredox reaction was investigated in the liposome dispersion. The rate of the photoredox reaction between internal [Fe(CN)₆]^3-(oxidizing agent) and external ascorbate or EDTA(reducing agent) mediated by phenosafranine was greatly increased by the addition of carbonyl cyanide m-chlorophenylhydrazone (CCCP)(Fig.1). Valinomycin also increased the reaction rate under the condition that K⁺ concentration in the external aqueous phase was the same as that in the internal aqueous phase. In the absence of K⁺ at external aqueous phase, however, valinomycin decreased the reaction rate. The lipophilic cation, tetraphenylphosphonium ion (PPh₄⁺), was found to be accumulated in the liposomes on irradiation, and released from them on cessation of irradiation or on addition of CCCP (Fig.2). These results suggested that the membrane potential was generated by the transmembrane photoredox reaction. PPh₄⁺ uptake was measured under various conditions, and the changes of the membrane potential calculated from the amount of PPh4+, which was accumulated in the liposomes, were discussed.

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The electrochemical characteristics of an electrode coated with oriented ethylhexadecylviologen, having redox sites of hydrophilic group were analyzed. Ethylhexadecylviologen was fixed stably on the electrodes by dimerization. The dimerization was depressed when the other detergent, octadecyltrimethylammonium chloride was added to disperse ethylhexadecylviologen (Fig.1). Electron transfer process at eectrode-solution interface was depressed by the coating of electroinactive detergent, e. g. oleic acid. Reduction half-wave potential of oxygen molecule of rotating disk voltammetry was shifted from -450mV to -530mV (vs. SCE due to this supression). On the other hand, the reduction half-wave potential of oxygen molecule was shifted to anodic side by 90mV when ethylhexadecylviologen was coated electrolytically on the electrode (Fig.5). It was clarified that the electrode coated with ethylhexadecylviologen as super thin layer showed catalytic activity f or the reduction of oxygen molecule.

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The effect of applied potentials on photocurrents at metal complex thin-film electrodes was, studied. Four different kinds of metalloporphyrins (Fig.1) and tris(2, 2'-bipyridine)ruthenium(II) complex were used.1x10¹⁵ molecules of each metal complex was coated on a Pt electrode (0.5 cm² in area). The methods of thin-film attachment were twofold and were described elsewhere. No redox. agents were added in sample solutions except for water and supporting electrolytes. The focusedi light of 400-800 nm range was applied. The photocurrent I, versus applied potential relationship I_p=f(E) was divided into three groups: Exponential, linear and others. The results were interpreted in terms of the film resistivity (≈10⁶Ω) which is uncompensated with the potentiostat and is changed with illumination. The second part of the present work is the comparison between a three electrode potentiostatic condition and a two electrode short circuited condition with no external load. Fig.6shows that the photocurrents are greater for the two electrode, system than those of three electrode system in both sides of extreme pH regions. This result suggests that the function of a potentiostat affects the photoinduced charge separation process in the metal complex thinfilm.. The above statement is further supported by the observation as following: At a tris(2, 2'bipyridine)ruthenium(II) thin-film electrode, a three electrode potentiostatic condition gave only 470 nm peak in the photocurrent action spectrum, whereas an additional 520 nm shoulder peak corresponding to a singlet-triplet direct transition was observed with a two electrode measuring system.

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Absorption spectra and photoelectrochemical properities were studied for thin films of several merocyanine dyes, each of which consists of a dihydrobenzothiazole or dihydrobenzoselenazole part having an octadecyl group (as a hydrophobic group) and of a rhodanine part. The change in quantum efficiency of the photocurrent at the electrodes coated with the dye films was investigated in connection with the formation of dye aggregates which showed visible absorptions in a low-energy region. Only the dyes having a carboxymethyl group at the rhodanine ring showed the absorptions of dye aggregates when the dye films were soaked in neutral aqueous solutions; the absorption bands located at 600 and 630 nm were assigned to the dye tetramer and hexamer, respectively. The extent of the aggregation was affected by the chemical structure of dye, the ionic strength of aqueous solutions, and the thermal isomerization of the dye molecules, etc. All the electrodes coated with the thin films of the merocyanine dyes behaved as the photocathodes. The aggregate formation gave an important effect on the photoelectrochemical energy-conversion, that is, the photocurrent increased remarkably with increasing the visible absorption of the dye tetramer or hexamer.

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Electrocatalysis of the reduction of oxygen and ethylenediaminetetraacetatoiron(III) complex was observed with the pyrolytic graphite electrodes coated with an intermolecular complex of poly(xylylviologen) polysulfonate. This coating film had high permeability to oxygen, so that every active viologen radical site of the polymer film could participate in the redu ction of oxygen. On the other hand, the reduction of the ethylenediaminetetraacetatoiron(III) complex which is catalyzed by viologen radical occurred in the vicinity of the polymer fil m/solution i nterface, since the Fe complexes can barely penetrate into the polymer film. The rate constants of the electron transfer cross-reaction between viologen active sites of the coating fil m and the substrates were determined from the detailed analysis of the stead y-state current potential curves which were obtained at the viologen-coated rotating disk electrode. Furthermore, the electrodes coated with the protonated poly(4-vinylpyridine), into which anionic metal complexes such as [W(CN)₈]^-4 were incorporated by electrostatic interaction, were prepared and the ability of the resulting film as a catalyst for the redox reaction of the Fe²⁺/³⁺ ion was examined.

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Institute of Technology; Nagatsuta, Midori-ku, Yokohama-shi 227 Japan General equations for the steady-state current-potential curves obtained with the rotating disk electrode voltammetry are derived for the electrocatalytic reaction of a dissolved substrate, where its reaction is mediated by the redox polymer coating films on electrode surfaces. The theoretical equations (Eqs. (36), (42), (43) and (44)) are given as a function of four characteristic currents which express the rates of the four rate-controlling processes:(1) the current of substrate diffusion from a bulk solution to the film/solution interfaces, (2) the current of electron cross-exchange reaction between a substrate and a catalyst confined in the polymer film, (3) the current of physical diffusion of a substrate within the polymer film, and (4) the current of the charge transport of a diffusion-like processes derived by electron self-exchange between catalysts within the film. It is reported that according to the difference of the rates among three rate-controlling reactions (2)-(4) mentioned above a systematic simplification of the theoretical equations (Eqs. (36), (42), (43) and (44)) can be made to elucidate some electrocatalytic reaction mechanisms obtained with film-coated rotating disk electrodes and to evaluate the relevant kinetic parameters.

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Electrochromic oxalatotungstate(V) complexes have been chemically deposited onto micro pores of anodic oxide films on aluminum formed in a phosphoric acid solution. The complexes were first adsorbed on the surface of the micropores and then converted into WO₃ by following heat-treatment at 300°C. Even after this treatment, some of the complexes may still remain on the oxide. Reversible coloration and bleaching were observed by cathodic and anodic polarization in a sulfuric acid solution.

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It was made clear that a blended membrane made of poly(3-vinyl-1, 4-butyrolactone-coacrylonitrile)and poly[3-(4-vinylphenoxy)phthalide-co-acrylonitrile] widely covered the selectivities in the K⁺-Na⁺-Li⁺ ternary system by changing both its composition and the fraction of opened lactone. Besides, the selectivities in the K⁺-Li⁺ binary system through various membranes were investigated. The selectivities observed by the piezodialysis method were good relative to the Dimroth's solvent polarity value, E_T(25°C), obtained by incorporating 1-octadecyl-3, 3-dimethyl-6'-nitrospiro[indoline-2, 2'-[2H] [1]-benzopyran] as an indicator. The tendency of the selectivity observed by piezodialysis method was opposite to that obseved by the active transport system or the electrodialysis method. It was suggested that the ET value is useful for the exploration of a novel membrane material.

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