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To improve the electrochemical characteristics of the natural graphite (NG-3) negative electrode in the LiCl saturated AlCl3-1-ethyl-3-methylimizadolium chloride + thionyl chloride (SOCl2) melt as the electrolyte for non-flammable lithium-ion batteries, we examined the influence of the binder types on its electrochemical characteristics. The cyclic voltammograms showed that the reduction current at 1.2–3.2 V vs. Li/Li(I) was repressed using polyacrylic acid (PAA) as the binder. The charge–discharge tests showed that the discharge capacity and the charge–discharge efficiency of the NG-3 electrode coated with the PAA binder at the 1st cycle were 322.8 mAh g−1 and 65.6%, respectively. Compared with the NG-3 electrode using the conventional poly(vinylidene fluoride) binder, it showed considerably a better cyclability with the discharge capacity of 302.1 mAh g−1 at the 50th cycle. Li(I) ion intercalation into the graphite layers could be improved because the NG-3 electrode coated with the PAA binder changed to a golden-yellow color after the 1st charging, and the formation of first stage LiC6 was demonstrated by X-ray diffraction (XRD) measurement. In addition, the XRD and X-ray photoelectron spectroscopy indicated that one of the side reactions during charging was the formation of LiCl on the graphite surface regardless of the binder types.

We have developed intermediate-temperature solid oxide fuel cell (SOFC) with a proton conducting oxide BaCe0.8Y0.2O3-δ(BCY20) as the electrolyte for direct utilization of dimethylether (DME) fuel. We tried to improve the cell performance of the SOFC by using Fe, Fe-Ni and Fe-Pd/MnO2 as a catalyst for the anode. Fe showed high catalytic activity for DME, furthermore attending Ni or Pd/MnO2 catalysts to Fe remarkably improved the cell performance.

We investigated an electroless aluminum plating based on using AlCl3–1-ethyl-3-methylimidazolium chloride (AlCl3–EMIC) ionic liquid with diisobutyl aluminum hydride (DIBAH) as a liquid reducing agent. The plating film was analyzed by measurements of X-ray diffraction, scanning electron microscopy with energy-dispersive X-ray analysis (SEM-EDX) and glow discharge optical emission spectroscopy (GD-OES). Consequently, a thick aluminum plating film with high uniformity was prepared from AlCl3–EMIC with DIBAH. No impurity phases were detected. Moreover, we discussed the reaction mechanism of the electroless aluminum plating.

We investigated electroless aluminum plating using AlCl3-1-ethyl-3-methylimidazolium chloride (AlCl3-EMIC) ionic liquid containing diisobutyl aluminum hydride (DIBAH) and BiCl3. The plating film was analyzed using X-ray diffraction and scanning electron microscopy. The aluminum films prepared with BiCl3 were smoother than those prepared without BiCl3. Furthermore, the plating bath stability was improved by addition of BiCl3.

Abnormal grain growth occurring on an electrodeposited copper film was investigated for defect prevention during electrolytic copper foil production. An electrodeposited copper film was formed on a titanium substrate. Then abnormal grain growth was observed using scanning electron microscope equipped with an energy dispersive X-ray spectrometer (SEM-EDX) and X-ray diffraction (XRD). Generation of abnormal grains depended on the method of pretreatment of the titanium substrate. Titanium particles generated by mechanical polishing during the pretreatment process were related to the abnormal grain growth. The preferred orientation of copper near titanium particle differed from that in the other parts of the film. Titanium particles were found to be involved in abnormal grain growth.

The negative electrode performance of the electroplated Al film electrode in the LiCl saturated AlCl 3 –1-ethyl-3-methylimizadolium chloride (EMIC) + SOCl 2 melt as the electrolyte for use in non-flammable lithium secondary batteries was evaluated. In the cyclic voltammogram of the electroplated Al film electrode in the melt, the oxidation and reduction waves corresponding to the electrochemical insertion/extraction reactions of the Li + ion were observed at 0–0.80 V vs. Li + /Li, which suggested that the electroplated Al film electrode operated well in the electrolyte. The almost flat potential profiles at about 0.40 V vs. Li + /Li on discharging were shown. The discharge capacity and charge–discharge efficiency was 236 mAh g −1 and 79.2% for the 1st cycle and it maintained 232 mAh g −1 and 77.9% after the 10th cycle. In addition, the initial charge–discharge efficiencies of the electroplated Al film electrode were higher than that of carbon electrodes. The main cathodic polarization reaction was the insertion of Li + ions, and side reactions hardly occurred due to the decomposition reaction of the melt because the Li content corresponding to the electricity was almost totally inserted into the film after charging.

We have ever proposed to prepare the highly functional material films by using an electrophoretic deposition (EPD) method. In this review, we have utilized the EPD process to fabricate the binder-free carbon negative electrodes for lithium ion secondary batteries; these electrodes were fabricated without mixing a binder. Powdered active materials are usually used for the electrode of lithium ion secondary batteries. The binder is used to form it as an electrode but is not concerned in charge-discharge reaction directly. Therefore, if it is not used for the electrode fabrication, it leads to high energy density of a battery. Artificial graphite powders could be deposited on the anode substrate by the EPD method. Smooth and uniform deposit could be obtained. It was shown clearly that the binder-free artificial graphite film functioned as the negative electrode for lithium ion secondary batteries. In addition, a co-deposited film consisting of activated carbon and Ketjenblack powder particles was investigated as the electrode for capacitor cells. It was found that the co-deposited film fabricated by adding polyvinylidine difluoride as a binder to the EPD bath operated successfully as it. From these results, it is concluded that the EPD method can be applied as the carbon electrode fabrication process.

We investigated crystal structure and ferroelectric properties of bismuth layered-structure compounds prepared by alloying Ce substituted Sr 1− x Ce x Bi 2 Ta 2 O 9 (SCBT) with Bi 3 Si 4 O 12 (BSO) using a solid state reaction method. From the P-E hysteriesis measurement, the SCBT has larger Pr and Ec compared with SBT. Pr increased and Ec decreased by adding BSO to SCBT. The crystal structure was determined by the Rietveld analysis using neutron powder diffraction data. The results of analysis indicated that the SCBT and that added with BSO had a larger spontaneous polarization, and a smaller tilting angle (α a ) in comparison with those of SBT. Moreover, the distortion of TaO 6 octahedron was changed in the SCBT and that added with BSO.

The stable geometries and formation processes of the AlmNan (m = 2-4; n = 1-8) clusters were investigated using the density functional theory (DFT). The Alm (m = 2-4) structures are maintained in the clusters. The Na atoms are attached to the Al-Al bond or Al plane for less than n = 4 in the AlmNan (m = 2-4) clusters. The odd electron of the attached Na atom is transferred to the Alm part for n ≤ 4 or 5 in the AlmNan (m = 2-4) clusters since the Alm part becomes stable. The Na-Na bonding is formed by the attached Na atom after saturation of the Al-Al bonds or Al atoms. The Al2Na5, Al3Na5, Al3Na6, Al3Na7, and Al3Na8 clusters have a characteristic structure. The Na wing is formed in the Al3Nan (n = 5-8) clusters. The 2S shell containing the 3s orbital of the Na atom and the 3p orbital of the Al atom becomes stable before the occupation of the 1D shell because the electrons are delocalized on the Na plane for n ≥ 5 in the AlmNan (m = 2-4) clusters. The stability of the AlmNan (m = 2-4; n = 1-8) clusters was evaluated by comparison of the vertical ionization potential (IP), HOMO-LUMO gap, adsorption energy of the Na atom, and binding energy per atom.

Since pervaporation performance of ethanol-permselective silicalite membrane, which is an aluminum-free hydrophobic zeolite, in the separation of fermentation broths by yeast are negatively affected by succinic acid, the potential of pervaporation using silicone rubber-coated silicalite membranes of ethanol fermentation broths, not containing succinic acid, by Zymomonas mobilis was investigated for the reliable production of concentrated bioethanol. In the separation of fermentation broths, the pervaporation performance was influenced by nutrients used for the preparation of fermentation broths. In the separation of a broth prepared with yeast extract, pervaporation performance was greatly compromised by accumulation of a substance(s) having an ultraviolet absorption maximum at approximately 260 nm not only in total flux, but also in permeate ethanol concentration compared to the separation of binary ethanol/water mixtures. When supplying a prepared broth with corn steep liquor without the accumulation of a substance(s) having an ultraviolet absorption maximum at approximately 260 nm, the permeate ethanol concentration did not decrease. Treating the prepared broth with activated carbon was effective in restraining the decrease in total flux. Pervaporation performance is also deteriorated by the adsorption of lactic acid contained in corn steep liquor onto the silicalite crystals. In the separation of ternary mixtures of ethanol/water/lactic acid, accomplished by adjusting the ternary mixtures to pH > 5, more than 90% of the permeation flux in the separation of binary ethanol/water mixtures was obtained, and the permeate ethanol concentration was comparable to that obtained in the separation of binary mixtures. For stably performing pervaporation, it is important to prepare ethanol fermentation broths by Zymomonas mobilis in which lactic acid concentration is as low as possible. Copyright © 2007 Society of Chemical Industry

The structures having the minimum interaction energy of the Li2CO3 monomer, dimer, trimer and tetramer were derived using the density functional theory (DFT). The structures of the monomer and the dimer agreed with the ab initio molecular orbital calculation results at a Hartree—Fock level. The structures of the trimer and the tetramer model were C3h and C2 symmetry, respectively. Then we carried out the harmonic frequency analysis of these geometries. The tetramer model showed the best agreement among these results with the Raman spectrum of the liquid state. On the other hand, we calculated the total structure factor S(Q) of the trimer and tetramer geometries considered from the DFT calculation to examine the local structure of molten Li2CO3. The calculation result corresponding to the tetramer model reproduced satisfactorily the position and the height of the S(Q) peaks. It was found that the DFT calculation of the tetramer model reproduced the S(Q) at the small Q region where the intermolecular correlations predominated.

We investigated a series of bulk, ceramic samples of Si-added bismuth layered-structure compounds, SBTS, prepared by alloying SrBi2Ta2O9 with Bi2SiO5 or Bi4Si3O12 using a solid-state reaction method. X-ray and neutron powder diffraction were carried out to determine the crystal structures. Structural information is correlated with the measured data of the ferroelectric properties. We find that remanent polarization and coercive electric field increase with the addition of Bi2SiO5 or Bi4Si3O12 in SrBi2Ta2O9. The dielectric constants of SBTS increase markedly with increasing temperature. It is found that the ferroelectric behavior is related to the distortion and tilting of the TaO6 octahedron that are effected by variations in Bi and Si contents, respectively, in the SBTS samples.

The techniques of neutron scattering were applied to characterize two rare-earth containing ceramic systems: oxide-based automotive three-way catalysts and proton-conducting cerate-perovskite-based hydrogen-separation membranes. High-surface-area zirconias are widely used as catalytic support of noble metals in automotive three-way catalytic converters for exhaust gas treatment. Doping these oxides with rare-earth elements provides an important means in tailoring their properties for better catalytic performance. We have carried out in situ small-to-wide angle neutron diffraction at high temperatures and under controlled atmospheres to study the sintering behavior and the Ce 3+ ↔ Ce 4+ redox process in Ce x Zr 1− x O 2− δ solid solutions dispersed with Pt nanoparticles. We found substantial effects due to RE-doping on the nature of aggregation of nanoparticles, defect formation, crystal phase transformation, and metal-support interaction. Y-doped BaCeO 3 exhibits significant proton conductivity under a hydrogen-containing atmosphere at high temperatures. This system has high potential for applications as fuel-cell electrolytes, gas sensors, and ceramic membranes for hydrogen separation. We have performed in situ neutron diffraction to obtain information regarding the crystal phase evolution that permits dissolution of hydrogen and proton migration through the lattice. Neutron quasielastic- and inelastic-scattering experiments were carried out to investigate the proton dynamics from local vibrations to long-range diffusion.

The tunnel growth mechanism of aluminum foil was studied in order to control the etching morphology. The growth of tunnels with a reversed taper followed by the tapered tunnel growth was observed only in acid solution. We proposed a model of the self-corrosion of aluminum for the reversed taper growth, and verified it by comparison of the current efficiency with the measured value made by ICP-ES to the simulation obtained from the results of the reversely tapered tunnel structure. From results of the early tunnel growth with a reversed taper, we discussed the relation between the limit length of the tunnel and width of the tunnel. It was expected that a uniform length of the tunnels should be obtained by controlling the width at the tunnel mouth to the same size.

We investigated the dependence of the properties, crystal structure and electrode characteristics on the heat-treatment of Li1.052Co1/3Ni1/3Mn1/3Oy. The crystal structure was determined by X-ray and neutron diffractions and Rietveld analysis. The electron density images were calculated by MEM/Rietveld analysis using X-ray diffraction. The discharge capacity increased, but the cycle performance was not good after a high PO2 heat treatment (450°C, PO2 2.03 MPa, 48 h, annealed). On the other hand, the cycle performance was improved by a reduced heat treatment (450°C, Ar, 48 h, annealed). Based on the crystal structural analysis, the bond length between 3b (transition metal site) and 6c (oxygen site) decreased with heat treatment in the reduction direction. From the distributions of the electron density, the (Li,Ni)[3a] site was localized and the covalent bond of (Co,Ni,Mn,Li)[3b]–O[6c] was weak due to the high PO2 heat treatment.

The aluminum-carbon nanotube composite (Al-CNT composite) much improves the properties of aluminum such as the toughness and the electrical conductivity. However, the manufacturing procedure for producing the Al-CNT composite requires multistage processes. We obtained electrolytically the Al-CNT composite coating from a 66.7 mol%AlCl3–33.3 mol%1-ethyl-3-methylimidazolium chloride bath containing CNT in a single process for the first time. We also visualized and clarified the process whereby solid particle such as CNT was co-deposited with the aluminum, and proved the co-depositing mechanism that previously had been understood only theoretically and conceptually. Namely, we show that the CNT was adsorbed on the cathode, and immediately seized by the initial depositing nucleus of the aluminum, then completely covered by both the grown nucleus and the newly generated initial depositing nuclei, and finally buried in the composite.

We investigated the preparation and characterization of the Pb–Zr–Ti–Nb–Si–O ferroelectric thick film by the electrophoretic deposition method. A ferroelectric material of (Pb,Si)(Zr1−x−yTixNby) Oz was prepared by the solid state method. The obtained samples were single phase, and the metal composition was controlled. The powder was charged into the acetone-iodine based electrodepositon bath after it was ultrasonically suspended. The maximum amount of the deposit was obtained when 1.5 g/l I2 and 5.0 g/l ferroelectric powders were added to a 100 ml acetone bath, and a uniform coating was obtained with an applied voltage at 180 V. The thickness of the film was controlled by changing the deposition time. The heat treatment condition of the deposited thick film was investigated and the conditions were 1000°C, O2, and 120 sec. The obtained thick film was relatively dense and uniform with a thickness of 15–30 µm at center position. Furthermore, the microstructure of the thick film was homogeneous. Based on these results, we obtained relatively good P-E hysterisis loops using Nb substituted Pb–Zr–Ti–Nb–Si–O thick films.

The electrophoretic deposition (EPD) process is one of several ceramic powder assembling technologies using a simultaneous colloidal process and electrochemical driving force. For the further development of the EPD technique, the possibility and the usefulness of preparing a thin and dense ceramic coating on non-electronically conductive porous tubular ceramics using the EPD technique was investigated. La 0.8 Sr 0.2 Co 0.8 Sr 0.2 O 3-δ (LSCF) was used as the deposition material and a porous alumina tube was used as the deposition substrate. Methanol (MeOH) was suitable as a dispersing medium for the LSCF powder. LSCF particles were positively charged in MeOH. For the fabrication of a uniform EPD layer, the cathode was placed in a porous alumina tube. The insides of the porous alumina tubes were filled with MeOH and the cathode did not make contact with the EPD bath. A 39μm (200 g/m 2 ) thick uniform LSCF powder coating was obtained by EPD at 100 V for 10 min. After sintering at 1500°C for 5 h, a 20 μm dense membrane was obtained.

Preparation of tubular silicalite membranes by hydrothermal synthesis with electrophoretic deposition (EPD) as a seeding technique was investigated. Two micrometers of small silicalite seeds were produced by an open-system hydrothermal synthesis at 100°C. These seeds were dispersed in 1-propanol and seeded on porous tubular stainless-steel supports by EPD; it had a high productivity and uniformity. The seeded support was then hydrothermally treated, and a tubular silicalite membrane was obtained. The pervaporation performance of this membrane showed a separation factor α of 70 with a total flux of 0.35 kg·(m2·h)−1 for a 5 vol% EtOH aqueous solution at 30°C.

We investigated the relationship between the electrode performance, crystal structure and electronic structure of LiMn1−xMxO2 (M=Mn, Co, Ni, Zn). The discharge capacity of o-LiMn1−xMxO2 decreased compared to that of LiMnO2. On the other hand, the cycle fading decreased since the maximum capacity was improved by substitution with Co or Ni. The crystal structure analysis by neutron powder diffraction was examined for LiMn1−yMyO2 (M=Co, Ni). The bond angle variances increased due to the Co or Ni substitution. The electron density distribution was obtained by XRD using the MEM/Rietveld method. The electron density distribution shows that the covalent bonding of (Mn,M)–O of LiMn1−xMxO2 is stronger than that of o-LiMnO2. Next, we calculated the net charge of each atom, the bond overlap population of Li–O, Mn–O, M–O, the density of states, and the electron density of o-LiMn1−xMxO2 using first principles calculation by the DV-Xα method and FLAPW method. Based on the results, the Li ionicity always remained high and the covalent bonding of Mn–O and M–O of each o-LiMn1−xMxO2 is stronger than that of o-LiMnO2. As a result, the covalent binding of (Mn,M)–O is important for good cycle performance.

The performance of a binder-free carbon-negative electrode was investigated using the LiCl-saturated AlCl 3 –1-ethyl-3-methylimizadolium chloride (EMIC) + SOCl 2 melt as the electrolyte for non-flammable lithium secondary batteries. Because the glass transition point of a LiCl-saturated 60.0 mol%AlCl 3 –40.0 mol%EMIC + 0.1 mol l −1 SOCl 2 melt was −86.2 °C, the melt could be used as the electrolyte in a low-temperature domain. The binder-free carbon electrode made by the electrophoretic deposition method was used as the negative electrode. Four kinds of carbon materials, i.e., artificial graphite, natural graphite, soft carbon, and hard carbon were evaluated as the carbon electrode. For 30 cycles, the discharge capacities of these electrodes were 296–395 mAh g −1 and the charge–discharge efficiencies were more than 90%. The melt can be used as the electrolyte for non-flammable lithium secondary batteries and the binder-free carbon-negative electrode operates quite effectively.

The lithium battery using Fe 3 O 4 fine particles has been constructed. The discharge characteristics were improved by the addition of India ink or polyvinyl alcohol (PVA). The discharge potential at 60 °C maintained 2.5 V versus Li/Li + up to 500 mAh g −1 and was 1.8 V at a large capacity of 926 mAh g −1 . The possibility of secondary battery was discussed from the result of cycling test with 926 mAh g −1 . Similar potential curve was obtained in the second cycle. Although degradation was observed in the third cycle, cyclability was maintained. However, the test cell stopped in fourth discharge. It is concluded that a large capacity was achieved at 60 °C using fine particles of Fe 3 O 4 with PVA additive. According to the cycling test, it is expected to be a secondary battery by further development in nanostructure of the cathode.

We investigated the relation between the cycle performance and crystal structural change during the charge–discharge process of LiMn 1.5 Ni 0.5 O 4 as a 5 V class cathode active material, which was prepared by changing the calcination temperature using the sol–gel method. The lithium content of Li 1− x Mn 1.5 Ni 0.5 O 4 ( x =0.5, 0.7, 1.0) was controlled by electrochemical lithium extraction. The crystal structure was determined by Rietveld analysis using powder neutron diffraction. As a result, all samples consisted of three phases (space group: P 4 3 32) of different lattice constants and Ni valences. The main phase, which has the maximum percentage, was shifted to a phase with a lower lattice constant with the decreasing lithium content, and then finally Li 1− x Mn 1.5 Ni 0.5 O 4 ( x =1.0) was almost oxidized to Ni 4+ by a charging process. Furthermore, LiMn 1.5 Ni 0.5 O 4, , by changing the synthesis temperature, was different for a few oxidation processes; the structure of the phase at Ni 3+ was not stable based on the distortion of each phase and the Madelung energy. It was suggested that these factors should provide an effective cycle performance.

In order to produce highly concentrated bioethanol by pervaporation using an ethanol-permselective silicalite membrane, techniques to suppress adsorption of succinic acid, which is a chief by-product of ethanol fermentation and causes the deterioration in pervaporation performance, onto the silicalite crystals was investigated. The amount adsorbed increased as the pH of the aqueous succinic acid solution decreased. The pervaporation performance also decreased with decreasing pH when the ternary mixtures of ethanol/water/succinic acid were separated. Using silicalite membranes individually coated with two types of silicone rubber, pervaporation performance was significantly improved in the pH range of 5 to 7, when compared with that of non-coated silicalite membranes in ternary mixtures of ethanol/water/succinic acid. Moreover, when using a silicalite membrane double-coated with the two types of silicone rubber, pervaporation performance was stabilized at lower pH values. In the separation of bioethanol by pervaporation using the double-coated silicalite membrane, removal of accumulated substances having an ultraviolet absorption maximum at approximately 260 nm from the fermentation broth proved to be vital for efficient pervaporation. Copyright © 2005 Society of Chemical Industry

In this study, the preparation of polyimide composite membranes was investigated by the electron beam (EB) irradiation method. The asymmetric polyimide membranes as substrates were prepared on the non-woven fabric by the phase inversion process. Electron beam irradiation was done on the polyimide membrane using the EB irradiation equipment with low acceleration voltage (50 keV) in the nitrogen atmosphere. Graft polymerization took place by soaking membranes after the EB irradiation in aqueous ethanol solution with various vinyl monomers. The performance of prepared membranes was evaluated by nitrogen permeability and by flux and separation factor for a benzene/cyclohexane (50/50, w/w) azeotropic mixture at 30 °C on pervaporation.

We investigated the relation between crystal structure, electronic states and electrode performance of LiMn2-xMxO4 (M = Zn, Ni etc.) as cathode materials for lithium ion secondary batteries. The cycle performance is improved by substitution of Mn with M. The crystal structure was determined by Rietveld analysis using powder neutron diffraction. The electron density distribution was obtained by XRD using MEM/Rietveld method. From the results, the stability of the host structure is important for cycle performance.

We investigated the crystal structure, physical properties and ferroelectric performance of bulk material obtained by mixing and sintering Bi 3.25 La 0.75 Ti 3 O 12 and Bi 4 Si 3 O 12 or Bi 2 SiO 5 for use as a novel ferroelectric material for ferroelectric memory. The resulting material was identified as a structure whereby, all of the peaks, as determined by powder X-ray and neutron diffraction, were the same as Bi 3.25 La 0.75 Ti 3 O 12 , and thus a single phase was obtained. Moreover, we investigated the crystal structure of the material by neutron diffraction, and the obtained results suggested that Si is substituted on Ti sites. The resulting material was investigated by SEM, and grains grown relative to Bi 3.25 La 0.75 Ti 3 O 12 were observed. Based on P–E hysteresis measurements, this sample has a high remanent polarization ( P r ) and a low coercive field ( E c ) relative to Bi 3.25 La 0.75 Ti 3 O 12 , as well as improved overall ferroelectric characteristics.

We investigated the relation between the electrode performance and electronic states of LiMn 2− x M x O 4 (M=Ni, Zn) as cathode active materials for the 4V class of lithium secondary batteries. The cycle performance is improved by substitution of Mn with Ni or Zn. We obtained the electron density distribution by XRD using the MEM / Rietveld method. Moreover, we investigated the electronic states of LiMn 1.75 M 0.25 O 4 (M=Mn, Ni, Zn) using first-principles calculation by the DV-Xα method. The net charges of each atom, and the bond overlap populations of LiO, MnO, NiO and ZnO were calculated. From the results, Li has a high ionicity and the covalent bonding of the MnO of LiMn 1.75 M 0.25 O 4 (M=Ni, Zn) is stronger than that of LiMn 2 O 4 . As a result of the DOS, the oxygen 2p orbital and Mn 3d orbital provides the overlap and the overlap of LiMn 1.75 M 0.25 O 4 is greater than that of LiMn 2 O 4 .

The enhanced reduction of hydrogen peroxide (H 2 O 2 ) and electrochemical current oscillatory phenomena during its reduction were observed on a mercury (Hg) adatom-modified Au polycrystalline electrode in alkaline, acidic and neutral aqueous solutions. The enhancement of the H 2 O 2 reduction was observed in the potential region from −0.2 to −0.6 V (vs. Ag ∣ AgCl ∣ KCl (sat.)). The enhanced reduction of H 2 O 2 was independent of the pH of the solution in the pH region from 3 to 10. The current oscillation occurred in the negative differential resistance potential region (−0.4 to −0.6 V). Its amplitude and the potential width in which the current oscillation was observed depended on the surface coverage of Hg on the Au electrode and the kind of anions in the solution. The observed enhancement of the reduction of H 2 O 2 and the current oscillation were explained by taking into account the local pH increase near the Hg adatom-modified Au electrode as well as the electrode potential-dependent electrocatalytic behavior of the adsorbed species of OH − (OH ad ) on the electrode surface.

LiMn 1.5 Ni 0.5 O 4 , as a 5 V cathode material, was prepared by changing synthesis method and heat treatment. We investigated the dependence of its properties, crystal structure and cathode performance on the oxygen content. The oxygen content of the samples (sol–gel method and annealed at a high P O 2 ) increased in comparison with the sample prepared by the solid-state method. The charge–discharge curves of the samples (solid-state method) had plateaus at 4.1 and 4.7–5.0 V. The 4.1 V plateau disappeared for the samples made by the sol–gel method or annealed at a high P O 2 . The discharge capacity with respect to cycle number of the 5 V region in the LiMn 1.5 Ni 0.5 O 4 (sol–gel method) electrodes shows an especially good cycle performance. The neutron-diffraction intensity profiles of LiMn 1.5 Ni 0.5 O 4 were analyzed. From these results, the samples are assigned to the ordered form (space group P 4 3 32). The amount of the impurity phase decreases by annealing at a high P O 2 or using the sol–gel method. Furthermore, the distortion of the Mn, Ni(12d)-O octahedral site was restrained by increasing oxygen content.

The electrochemical deposition of Zn–Ni alloy from ambient-temperature molten salts ZnCl2–NiCl2-1-ethyl-3-methylimidazolium chloride (EMIC) and ZnCl2–NiCl2–EMIC–ethyl alcohol (EtOH) was examined. The Ni content in the deposits could be controlled continuously from 12.3 to 98.6 mol.% by changing the bath composition, temperature during the electrodeposition, and current density in the ZnCl2–NiCl2–EMIC and ZnCl2–NiCl2–EMIC–EtOH melts. The X-ray diffraction patterns of the deposit obtained in the electrodeposition from the ZnCl2–NiCl2–EMIC–EtOH melt showed a broad peak. The results of the differential scanning calorimetry experiments for the deposit showed exothermic peaks that are considered to be due to the amorphous-to-crystalline transformation and crystal growth. The formation of the amorphous structure on the deposit was confirmed.

Three mannosylerythritol lipids (MEL-A, -B, and -C), yeast glycolipid biosurfactants, were independently attached to poly (2-hydroxyethyl methacrylate) beads (PHEMA), and the three obtained MEL-PHEMA composites were examined for their binding affinity to human immunoglobulin G (HIgG). Of the three composites, the composite bearing MEL-A exhibited the highest binding capacity for HIgG. The binding amount of HIgG increased with increased applied concentration, reaching 106 mg HIgG (per g of composite), with a binding yield of 81%. Interestingly, the protein binding to the composite appeared to follow two different modes (Langmuir type and Freundlich type) depending on the applied concentration. The binding amount of human serum albumin to the composite was much smaller than that of HIgG. The bound human serum albumin, however, had minimal effect on the subsequent binding of HIgG, indicating that the two proteins have different binding sites onto the composite. More significantly, the bound HIgG was efficiently recovered under significantly mild elution conditions: Approximately 90% of the protein was eluted from the composite with phosphate buffer at pH 7. These results indicate that the glycolipid biosurfactant may have great potential as an affinity ligand material for HIgG.

Electrochemical oxidation of glucose at Hg adatom-modified Au polycrystalline electrode was examined in alkaline aqueous solutions using cyclic voltammetry. Two oxidation current peaks for glucose were observed on Hg adatom-modified Au electrode at almost the same potentials as those observed on a bare Au electrode. The oxidation peak currents were much larger than those on a bare Au electrode in the concentration range from 0.5 to 20 mM. The observed enhancement of the glucose oxidation was considered to be due to the increase in the amount of the adsorbed OH− on the Hg adatom-modified Au electrode. The reaction was catalyzed through the pairing of glucose and the intermediate in the oxidation to the large amount of the adsorbed OH− on the Hg adatom-modified Au electrode. Keywords: Glucose, Mercury adatom-modified electrode, Underpotential deposition, Electrocatalysis

A coupled fermentation/pervaporation process for reliable production of concentrated ethanol was studied using ethanol permselective silicalite membranes coated with two types of silicone rubber, KE-45 and KE-108, as a hydrophobic material. Ethanol recovery was greatly improved by using a membrane coated with KE-45 silicone rubber. The recovered ethanol concentration in the permeate was 67% (w/w), and the amount of recovered ethanol from the broth was more than 10 times higher than that using a non-coated membrane. Succinic acid and glycerol, by-products created during fermentation, interfered with the pervaporation performance of the coated membrane when used to separate an ethanol/water solution. Copyright © 2003 Society of Chemical Industry

In order to improve the pervaporation performance of silicalite membrane, two types of silicone rubber, KE45 and KE108, were coated on the membrane surface. The initial molecular weight of KE108 is high and vulcanizing starts when it comes into contact with moisture in air, whereas the initial molecular weight of KE45 is low and vulcanizing starts when it is mixed with a catalyst. KE108 was found to be more effective than KE45 in enhancing the ethanol selectivity of silicalite membranes. A membrane coated using a 3 wt.% KE108 hexane solution showed separation factor of α=125 with a total flux of 0.14 kg/m2 h.