A three phase liquid membrane system, consisting of an aqueous phase dissolved with a surfactant, a nitrobenzene phase with picric acid, and another aqueous phase, is known to generate electric pulses similar to the synapse system. The construction of a convenient apparatus consisting of a hollow tube and a beaker to form three phase system was described in this paper. The apparatus is capable of observing the electric pulses with relatively high reproducibility. It was found that the stability of oscillation depends considerably upon the material of the apparatus. When a Teflon hollow tube was used, the oscillation became more stable, compared to the case of glass tube. This stabilization seems to be caused by the change in the interface between three phases, aqueous phase, nitrobenzene phase, and the tube (solid phase). It can be concluded that the oscillation involves this interface. The amplitude, frequency, and profile of the oscillation, were found to change gradually in the course of time, and in total, three oscillation modes was observed. In the first stage, sharp electric pulses were observed at both interfaces between aqueous phases and nitrobenzene phase, while in the second stage, the periodic zigzags were observed only at one side of the interfaces. In the third stage, the oscillation was rather random and was observed only at a side where the second stage oscillation was observed. Based on these results, a new mechanism for the oscillation in the liquid membrane system is proposed.

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Catalytic hydrogenation of C = O and C = C group in methyl oleate dimer has been studied over heter ogeneous Rh-Sn bimetallic catalysts in liquid phase. The Rh-Sn bimetallic system was one of effective catalysts for hydrogenation of C = O group in methyl oleate dimer. No hydrogenation of C = O group was observed over the monometallic Rh catalyst. The activity for C = 0 hydrogenation increased with in creasing Sn content, whereas the activity for C =C decreased. Reduction temperature of the catalyst precursor prior to the reaction strongly affected the activity. The C= C hydrogenation activity decreased with the increase in the reduction temperature. The higher temperature would be required in order to reduce tin in the precursor to low valent state followed by alloying with Rh. Tetraethyltin or SnCl₂ were found to be effective as a Sn precursor for the hydrogenation of C= O. Alumina and TiO₂were appropriate supports studied here. Acidic supports enhanced the side reaction, that is, a tran sesterification reaction.

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The reductive amination of nonanal with ammonia over group 8 metals has been studied in ethanol at 50° C a nd 8 MPa-H₂ to compare the selectivity of these metals for the formation of the primary amine (nonylamine), the secondary amine (dinonylamine) and the tertiary amine (trinonylamine). The yield of the primary amine increased in the order: Pd < Os < Pt < Rh < Ir < Raney Ni = Ru < Raney Co. High yields of the primary amine were obtained with Raney Co (94%), Raney Ni (87%) and Ru (87% ) as catalysts, while over Pd catalyst the yield was o nly 24% which was t he smallest of t he metals investigated. Over Pd and Os catalysts the secondary amine was formed in larger amounts than the primary amine (62 and 53%, respectively). The tertiary amine was formed only in small amounts over Pd an d Os catalysts (6 and 1 %, respectively). In general, the formation of t he primary amine was n ot increased by the addition of a mmonium chloride. On t he other hand, the formation of the tertiary amine was greatly increased over Pd catalyst from 6 % to 45% in the presence of ammonium chloride. The max imum amounts of the Schiff -base, N-nonylidenenonylamine, found as an intermediate during the reaction were 69% over Raney Ni, 67% over Raney Co a nd 53% over Ru which were in a ll cases much greater than the amounts of the secondary amine produced over the respective metals. These results in dicate that the reaction pathways leading to the formation of the primary amine involves t he one via th e Schiff base as the intermediate which may be decomposed into t he primary amine and 1-nonanimine, by the ad dition of ammonia. Significant amounts of N, N-dinonyl-1-nonenylamine, a tertiary amine precursor, were also formed as an intermediate during the reaction even w hen the tertiary amine was n ot formed at all. The results show that, similarly to t he Schiff base, the tertiary amine precursor may be decomposed into the secondary amine and the imine in the presence of ammonia. The different sel ectivities of catalyst metals for the formation of primary and secondary amines have been discussed on the basis of the reaction pathways which involve the isomerization of the Schiff base to the enamine.

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In order to clarify effects of host micas and intercalated aluminum ion speices on thermal durability and microporous characteristics of alumina pillared fluorine micas, high layer charged synthetic expandable micas, Na-taeniolite NaMg₂LiSi₄O₁₀F₂ and Li-taeniolite LiMg₂LiSi₄O₁₀F₂, were used as host crystals for complex formation with three different kinds of hydroxoaluminum solutions, prepared i) by titrating sodium hydroxide solution in aluminum chloride solution, ii) by dissolving Al metal in HCl, and iii) by treating hydroxoaluminum solution with zeolite, respectively. The pillared fluorine mica formed from the solution containing a homoionic hydroxoaluminum speices (Al-polymer), which is obtainable by treatment with zeolite, has higher thermal durability than the pillared fluorine mica formed from the solution containing both Al-monomer and Al-polymer. This is probably due to the high pillar density, characterized by homogeneous Al-polymer packing into the interlayer region. When hydroxoaluminum solution treated with zeolite is used for complex formation, the alumina pillared fluorine mica obtained from Na-taeniolite via its Li⁺-exchanged form has larger thermal durability than that obtained from Li-taeniolite due to the difference in morphology and crystallinity of host mica crystals, exhibiting high surface area of 340 m²/g and micropore volume of 0.07 cm³/g at 600° C of heating temperature.

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On adding Triton X-100, a nonionic surfactant, to an aqueous solution of cobalt (II) containing some alkali metal or alkaline earth metal thiocyanates in excess, a deep blue tarry gel deposited. The gels were stoichiometric adducts such as M^J₂ [Co(NCS)₄] ⋅ 2Triton or M^II [Co (NCS)₄]⋅ 2Triton. These compositions remained essentially constant despite using various concentrations of Triton except barium salt. Counter ion of thiocyanate had a serious effect on gel formation. Lithium, magnesium, and calcium thiocyanates produced no analogous gels, while barium thiocyanate formed non-stoichiometric Triton adduct, which precipitated even without cobalt (II). The yields of such blue gels were observed in the following order: Ba²⁺ > K⁺ =Rb⁺ > Cs⁺ > NH⁴⁺ > Sr²⁺ > Na⁺. The recovery of cobalt (II) remaining in the supernatant liquid was minimized for all counter ions when the initial addition was conducted at a molar ratio of Triton/Co (II) =2.

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In order to change carbonylhemoglobin (HbCO) to oxyhemoglobin (HbO₂), the photodissociation of HbCO and O₂-binding to hemoglobin were studied using Hb liquid membrane system in O₂ atmosphere. The reduction rate of HbCO increased with illuminance and saturated nearly at 2.0.10⁵Lx. under a constant O₂ pressure of 760 Torr. The reduction rate of HbCO was a 5-fold low when the partial O₂ pressure was decreased from 760 to 0 Torr under the illuminance. In the static liquid membrane the exchanging rate of CO ligand in HbCO was decreased with the increment of the thickness of the liquid membrane, while the stirred liquid membrane showed a reverse result. The ligand exchange apparatus was made based on the obtained results, and the high flow rate of Hb solution enhanced the reduced amount of HbCO. Moreover, when the ligand exchange of Hb-vesicle dispersion was compared with an Hb solution, it proceeded more efficiently due to the encapsulation of concentrated Hb into a small compartment dispersed in a buffer solution.

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In order to correlate size and content of free volumes present in amorphous region of these polymers and the mechanical and dynamical properties of elastomers, positron annihilation peak profile analysis and lifetime measurements were carried out from 30 K up to meltimg temperature for several poly(methyl-vinyl-siloxane) containing silica glass powders. S parameter and mean lifetime were adopted as a perspective measure for the rough estimation of the multiplied size and content of free volumes and proved that these parameters worked as a simple measure of the over-all free volumes. The free volume dia meters of poly ( methyl-vinyl-siloxane) (KE-931-B and KE-931) and poly(methyl-vinyl-siloxane) (KE-951 and KE-971) increased with the elevation of temperature from about 0.63 nm (30 K) to about 0.82 nm (T_m: 225 K) and from about 0.52 nm (30 K) to about 0.80 nm (T_m: 225 K), respectively. The fre e volume content (I₃) of poly ( methyl-vinyl-siloxane) (KE-951 and KE-971) is constant from 30 K (20.5% and 26.5%) to 150 K (T_g) and increased to about 29% and 37% at melting point (225 K), respectively, whereas those of poly (methyl-vinyl-siloxane) (KE-931-B and KE-931) increased from 28% and 20.5% (30 K) to 54% and 43% (225 K) monotonously. The presence of pseud cross-linkage among silan ol groups at the interface of elastomers and silica powders was suggested because both size and content of free volume were reduced by the increase of silica powder concentration in the elastomers. The Laplace inversion was applied to positron annihilation decay curve and obtained size distribution of free volume.

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The simultaneous measurements of gel-melting temperature (T^g_m) and the differential thermal analysis (DTA) of linear high-density polyethylene (LHDPE)-decalin gels prepared at various cooling rates from solutions were performed. Combining these results with the morphological change of LHDPE crystallites during the melting of gel, the relationship between T^g_m and fusion process of the gel was investigated. The thermal gravity measurement of gel samples, where platinum ball was placed, revealed that a deceptive gravity change appeared at T^g_m as if the gravity decreased for a moment. The DTA measurement of each gel sample showed that the endothermic curve for fusion of the gel split into two peaks when the cooling rate of solution became faster and that T^g_m was located between the two (lower and higher temperature) peaks. As such splitting endothermic peak includes the exothermic process for the reorganization of the quasi-stable element, endothermic peaks of decomposed DTA curves into the sta ble and quasi-stable elements were deduced by the method reported previously by the present authors. From analysis of the deduced endothermic peaks, it was found that the ratio of the peak area till T^g_m to the total area of those endothermic peaks was almost constant near 0.6-0.7 irrespective of the cooling rate and composition of gel. The morphology of LHDPE crystallites in the gel quenched immediately after continuous heating till just below T^g_m unchanged but that quenched after heating till just above T^g_mchanged to curly and somewhat complex shape in all gel sample. These results imply that when the fusion of the gel reaches to ca.60% of whole heat of fusion, the three dimensional network structure of the gel is released due to that LHDPE crystallites initiates to melt from the outside.

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Surface modification of nonwoven fabrics of polyolefin by graft polymerization of acrylic acid initiated by low temperature plasma was investigated to develop a new durable separator for secondary battery. The fabric, the thickness of which was 210 pm with 78 g/m²-fabric-density, was made of a two-component-fiber of 20 pm-diameter that consists of polyethylene surface on a core of polypropylene inside. The fabric was exposed to argon plasma under conditions of gaseous pressure of 13.3 Pa and 13.56MHz-RF-wattage of 10 W before introducing monomer vapor for graft polymerization at 299 K. Graft ing ratio (GR) estimated on weight basis of a piece of the fabric increased from 1.8% to 4.9% with graft polymerization time from 60 s to 10800s on 60s-plasma-exposure-time. However, GR was alomst constant of around 0.7% independent of plasma exposure time up to 300 s for 60 s-graft-polymerizationtime. By C_1s (289 eV) and O_1s, (535 eV) peaks of X-ray photoelectron spectroscopy (XPS), chemical bonding of acrylic polymer chains to fabric surface could be confirmed. It was also observed that the degree of electrolyte retention which is important as a battery separator increased up to 267% for a surface modified fabric of 0.4%-GR by only 30 s-graft-polymerization-time after 60s-plasma-exposuretime. This retention value is comparable with that of a conventional polyamide separator.

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The sol-gel processing was applied to the fabrication of Pb (Ti, Zr) O₃ fibers. The Pb (OOCCH₃)₂⋅ 3H₂O, Ti ( OⁱC₃H₇)₄ and Zr (OⁿC₃H₇)₄ were refluxed with stirring in 2-methoxyethanol to form Pb(II)2-methoxyethoxide and Ti-Zr 2-methoxyethoxide, respectively. And then both alkoxides were mixed with stirring in 2-methoxyethanol to form Pb, Ti, Zr complex alkoxide. This complex alkoxide was hydrolyzed. The fibers could be drawn from the sot-solutions after the viscosity reached about 10 poise. Water in the alkoxide solutions was consumed for the hydrolysis and polycondensation reaction progresses to give polymerized products, and as a result the viscosity of the solution increases. The Pb (Ti, Zr) O₃ gel fibers were drawn from the spinnable viscous solutions. The fibrous Pb (Ti, Zr) O₃ gels fired at 650° C formed the well-crystallized perovskite Pb (Ti, Zr) O₃. Size of the fibers are a few centimeters long and from 10 to 100 μ m in diameter. On Pb (Ti, Zr) O₃ fibers, almost of grains have thin plate shape, and their size is 2.0 to 4.0 μ m in diameter and 0.1 to 2.0 μ m in thickness. This fiber was made up aggregation of thin plate.

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The potential-step chronoamperometry method has been applied to Pt/yttria-stabilized zirconia and Pt/samaria-doped ceria air cathodes, and current decay curves in response to applied potentials have been measured. It was assumed that oxygen ad-atoms formed by dissociative adsorption on platinum surface diffuse through the platinum electrode-solid electrolyte interface and then are reduced electrochemically to oxide ions. A decay equation was derived on the basis of the above reaction model. The kinetic parameters involved in it were determined by curve-fitting to the experimental values. The exchange current density and interfacial diffusivity were calculated from the parameter values thus obtained.

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In order to reinvestigate the interpretation of the data reported with respect to ¹H-NMR spectra of la-hydroxyvitamin D₂ (1a) and (24S) -1α -hydroxyvitamin D₂ (1b), 1b and 28-deuteriated vitamin D₂derivatives (1c) were synthesized efficiently via C-22 aldehyde (2). Both 1a and 1b have been examined by ¹H-NMRs pectroscopy to clarify that 1) the ¹H-NMRs ignal assignments of the 21-H and 28-H were reverse in previous data, 2) two doublets (J=6.6 Hz) due to the 21-H of 1a and 1b are clearly observed at δ =1.017 and 1.009, respectively.

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t is a well-known result that the reactions of t-alkyl halides with alkali metal aryl oxides and alkoxides in protic solvents give olefins (E) almost exclusively. By contrast, we found a new method for the Williamson ether synthesis in the reactions of t-alkyl halides with alkali and alkaline earth metal phenoxides and alkoxides at 60-90° C in nonpolar solvents (hexane and heptane). The yields of t-alkyl phenyl ethers and t-butyl alkyl ethers (SN) were moderate. The selectivity of SN/E was governed by solvent, metal cation (Li⁺, Na⁺, K⁺, Mg²⁺, Ca²⁺, Sr²⁺, and Ba²⁺), nucleophile, and substrate. The nonpolar solvents were much more effective for the SN reaction than polar solvents.

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