In order to obtain thinner Ni electrode layers for MLCCs, BaTiO3 organometal resinate was added into Ni paste which consisted of 100nm Ni powders. Ni electrode films were fabricated with the Ni paste added with BaTiO3 organometal resinate, and sintering and electrical characteristics of the film were examined in the present study. The experimental results indicated that addition of BaTiO3 organometal resinate remarkably suppressed the sintering of the Ni electrode films, i.e., no abnormal grain growth was observed on Ni electrode films with BaTiO3 organometal resinate. In addition, MLCCs with 10stacked layers was experimentally fabricated. And the capacitance, the dielectric loss and insulating resistance of MLCCs were measured. The results indicate that even when the of BaTiO3 organometal resinate added is, the electrical characteristics of the MLCCs are not impaired regardless of the nano-size of the Ni particles. An addition of BaTiO3 organometal resinate was found to be extremely effective for obtaining thin electrode layers.

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The X-ray refraction imaging technique, diffraction-enhanced X-ray imaging (DEI) method was applied to determine the hydrogen diffusivity in titanium-hydride. Hydride was formed on titanium surface by electrolytic-charging at room temperature for 6, 12, 18, 24 and 48 h. The specimen was cut into a 1-mm thick slice for cross-sectional observation. Hydride layer was observed by DEI method as a thick black or white line parallel to the surface. Hydride distribution caused by hydrogen diffusion from the surface was calculated using assumed hydrogen diffusivity and a solution of diffusion equation. And the results were converted to the intensity profile of refraction images of the hydride using the measured rocking curve from an analyzer. The intensity profile was compared with that obtained from the photographs and fitted diffusivity was decided by trial and error. The obtained diffusion coefficient of hydrogen in titanium-hydride, 3.6 x 10^-15 m-2/s, was slightly larger than the value obtained by internal friction at room temperature.

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A novel medium-energy synchrotron capable of accelerating all ion species is proposed as an ion driver for exploring new paradigms in material science. All ions, including cluster ions in their possible and arbitrary charge state, are accelerated in an injector-free single accelerator. The principle of accelerator is based on that of the induction synchrotron, which has been recently demonstrated at KEK. Various high-energy ions provided from the ion driver will be used in a way of penetration through bulk materials leaving large substantial electroexcitation energy. Uniform or localized implantation of energetic ions into the materials are rather general but still attractive approaches to create novel materials, such as a shock absorbing alloy with a soft layer underneath hard surface.

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Micro-scale tools, such as punch tools, used in die-forming processes to fabricate micro-scale mechanical devices currently have a relatively short lifespan. The ion implantation method studied in the 1980s shows promise for improving the lifespan of micro punch tools. In this study, 150 micro m-diameter holes were punched in a 0.2-mm-thick stainless spring steel by using a punch tool. Ion implantation of the punch tool using silicon or gold species decreased the lifespan of the tool. However, the punch tool was then annealed at 700 K for 30 minutes after ion implantation, the silicon-ion implanted punch tool apparently restored its lifespan to that of an 'un-processed' punch tool (no ion-implantation or annealing). Moreover the gold-ion implanted punch tool had a lifespan 10 times longer than an un-processed punch. In conclusion, rearrangement of the disordered lattice caused by ion-implantation damage improves the toughness of micro punch tools.

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Boron-Carbon-Nitrogen (BCN) films are deposited on Si (100) substrates by RF sputtering with a mixture of Ar and N2 gases using a target of graphite combined with semi-circled boron carbide (B4C). A couple of the films located at the positions faced to B4C (BC) and graphite (G) sides are prepared at the same time, and their microstructure and mechanical properties are examined against the substrate bias modes, DC, uni- and bipolar pulses. The films are also examined as a function of the duty cycle in unipolar pulse. The results show that the concentration of C in the G side films is larger than those of the BC side films. For the unipolar pulse mode, the composition and the surface morphology are not significantly affected by the duty cycle. However, the maximal of the mechanical properties of the G side film in hardness and wear resistance are obtained at the duty cycle of 500 micro s. For the bipolar pulse mode, h-BN phase is increased in amount as compared with the unipolar pulse mode. In addition, the B concentration is increased and the mechanical properties are decreased in the BC side films, while, the N concentration is increased and the mechanical properties are increased in the G side films. These effects of the bipolar pulse mode are similar to those of the negative DC mode.

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The preparation of B-C-N films are attempted using trimethylborate (TMB: BO3(CH3)3) and N2 gases by a bipolar-type plasma based ion implantation method, and the influences of C7H8, Ar and H2 additional gases on the possibility of film formation are examined. It is found that no film is obtained using only TMB or TMB and N2 gases (TMB+N2). In the case of C7H8 addition to TMB+N2 system, the films composed of B, C, N and O are deposited. However, the deposition rate is significantly decreased as compared with the deposition of diamond-like carbon films using only C7H8 gas under the same deposition condition. As for Ar addition to TMB+N2 system, it is possible to deposit the films. However, FT-IR results suggest that BOx:H films are formed. On the other hand, H2 addition to TMB+N2 system makes the deposition of BCN:O,H films achievable, although the deposition rate is relatively low. In current experiments, O atoms still remain in the films even as a reduced gas of H2 uses. However, these results suggest that the film deposition using TMB+N2 system is strongly affected by the additional gases.

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SiCx films were prepared by a hybrid process of plasma-based ion implantation and deposition using hexamethyldisiloxane (HMDSO) gas including silicon. The SiCx was composed of carbon, silicon, oxygen, and hydrogen. The Si/C in film is 0.34 without negative pulsed voltage, but Si/C is increased with increasing the negative pulsed voltage to 0.56. The hydrogen of 20 - 30 at.% was included in the SiCx film. The residual stress of SiCx film was decreased with increasing ion implantation voltage from 0.2 GPa (compressive stress) to -0.2 GPa (tensile stress). The Vickers hardness of SiCx film was increased from 900 HV with -5 kV of ion implantation voltage to 1800 HV with -20 kV. A SiCx interlayer of 10 micro m in thickness was produced between the DLC film of 1 micro m in thickness and the aluminum alloy (A5052) substrate. Adhesion strength of DLC/SiCx/A5052 system was improved considerably.

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In this study, we investigated the adhesion strength and optical transparency of a-C, a-C:H, a-C:H:Si and SiO2 films deposited on polycarbonate. The a-C and SiO2 films were deposited by ECR-type ion beam sputtering system (ECR-type IBS), and the a-C:H and a-C:H:Si films were prepared with bipolar-type plasma based ion implantation (bipolar-type PBII). It is observed that the friction signal of the polycarbonate decreases due to the diamond-like carbon (DLC) coating, and the a-C:H:Si coating shows the lowest friction force. The a-C:H:Si film on the polycarbonate shows higher critical load, i.e., higher adhesion strength, compared to those of the a-C, a-C:H and SiO2 coatings. The transmittance increases due to the Si-addition to the a-C:H film in a wavelength range of 400 - 800 nm (visible range), whereas decreases in a wavelength range of 200 - 400 nm (UV range). The a-C:H:Si coating exhibits a larger optical band gap compared to those of other coatings due to highly sp3 dominant bonding structure. The a-C:H:Si is effective protective-coating for the polycarbonate due to its lower friction higher adhesion strength, higher transmittance in the VIS range and better UV protection ability compared to those of other coatings.

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Diamond-like carbon (DLC) films were prepared on the SUS304 substrate with a hybrid process of plasma-based ion implantation and deposition using toluene plasma. The pinhole defects in DLC films reached to the substrate deteriorate corrosion resistance. The area ratio of pinhole defects to the bare substrate was evaluated by the critical passivation current density (CPCD) method. The CPCD measurement indicated that the area ratio of pinhole defects in the DLC film was decreased with increasing film thickness and reached to about 1 x 10^-3 % at more than 6 micro m in thickness. The apparent area ratio of pinhole defects were also reduced by the interfacial treatment before DLC deposition such as the production of an interfacial mixing layer by carbon ion implantation to the substrate or the formation of SiCx nanolayer in front of substrate in the thinner film thickness. The ultrasonic cleaning in the acetone during the deposition reduced the area ratio of pinhole defects to 6 x 10^-4 % at the DLC film thickness of 1 micro m.

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BaTiO3 thin films were deposited on silicon substrates by ionizing oxygen gas in evaporating Ti metals and BaCO3 compounds. BaTiO3 films were deposited after very thin films of TiN were deposited on Si substrates to prevent the oxidation of Si surfaces. The deposited BaTiO3 thin films had tetragonal (t-) polycrystals oriented to the (101) crystalline plane. A BaTiO3 film deposited using oxygen ion beams with an energy of 100 eV and a current of 0.16 mA/cm2 had a large saturated polarization value of 39 micro C/cm2 and a polarization-electric field (P-E) hysteresis loop with a remanent polarization of 7.3 micro C/cm2 and a coercive field of 102.9 kV/cm. Their remanent polarization values decreased when the energies of oxygen ion beams were increased and decreased from 100 eV.

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Secondary ions emitted from a Si target have been investigated under large Ar cluster ion bombardment. Incident ion beams with energies from 10 to 30 keV were used and the mean size of the Ar cluster ion beam was about 1000 atoms per cluster. Secondary Sin^+(n=1-11) ions were measured from Si under Ar cluster ion bombardment, while only atomic ions were measured under Ar monomer ion bombardment. In this study, we succeeded to accurately measure the incident size dependence of secondary ion spectra for Si under large Ar cluster ion bombardment using a time-of-flight technique combined a primary-ion beam deflector and a secondary-ion deflector. When the total incident ion energy was kept constant, the yields of secondary cluster ions such as Si6^+ relative to those of Si^+ increased with size. On the other hand, when the incident Ar cluster size was kept constant, the yields of secondary cluster ions relative to those of Si^+ decreased with energy. The effect of incident cluster size on secondary ion yields is discussed.

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Secondary ion emission from bio-molecular samples bombarded with ion beams was investigated. Emitted ions from arginine amino acid thin films were measured using a time-of-flight method under 10 keV Ar and 500 keV Au ion bombardments. For 500 keV ion irradiation, the molecular ion yield was about 1 x 10^-3 molecules/ion, which was 2 orders of magnitude larger than with 10 keV ion irradiation. As there are very few data on sputtering of bio-molecules under sub-MeV-energy range, the present work will contribute to understanding of emission mechanism caused by ion-beam irradiation.

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We implanted germanium negative ions into a 100-nm-thick SiO2 layer on Silicon substrate and have investigated about oxidation of implanted Ge atoms and cathode luminescence for the possibility of blue light emission. The ions were implanted into the same SiO2 layer with three times at different energies of 50, 20, and 10 keV (multi-energy implantation). The dose amounts were 1.4 x 10^16, 3.2 x 10^15 and 2.2 x 10^15 ions/cm2, respectively. Samples were annealed for 1 h at a temperature less than 900°C. The depth distribution and oxidation of implanted Ge atoms in the oxide were measured by XPS analysis with Ar etching. The depth profiles were well agreed with the cross-sectional TEM image. But some extent of Ge atoms diffused to the SiO2/Si interface at 900 °C. The chemical sifted spectra of Ge 2p3/2 showed about 60 % of the oxidation of Ge atom around the end of the range (EOR) even in the as-implanted sample. This oxidation was considered to be due to the excess oxygen atoms near EOR by forward of sputtered oxygen atoms from SiO2 layer. In cathode luminescence measurement, the Ge-implanted sample after annealing at 800°C showed strongest CL peak at 3.12 eV (397 nm in wavelength) in UV-blue region at room temperature. This means the Ge-implanted sample has a possibility for light emission in the UV-blue region.

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Germanium nanoparticle in SiO2 is expected to be use to a charge trap, light emission source, etc. Ge nanoparticles can be formed in silicon dioxide films by negative ion implantation and heat treatment. However, under the heat treatment, these nanoparticles may be oxidized by residual oxygen in heat treatment atmosphere, or combination with oxygen in a silicone oxide film. The XPS analysis showed the oxidation of some implanted Ge atoms. Raman spectra were investigated to confirm the existence of Ge-Ge bonds in the nanoparticles. Ge negative ions were implanted into a thermally grown 100 nm-thick SiO2 film on Si substrate. After implantation, the samples were annealed at various temperatures. After annealing at temperature more than 600°C, each Raman spectra showed a peak around 270 - 300 cm^·1. These peaks corresponded to the Ge-Ge bonding depending on the size of Ge nanoparticles. The sample after annealing at 800°C showed strong peak at 300 cm^-1. The largest Ge nanoparticles are expected to form in the layer. However, there is no peak in the sample after annealing at 900°C.

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Al-doped ZnO (AZO), Ga-doped ZnO (GZO), and GZO/AZO thin films were deposited on polymer (PET) substrates with and without a ZnO buffer layer by using an r.f. magnetron sputtering technique and their structural, electrical, and optical properties were investigated to develop transparent conductors for flexible display applications. The transparent conducting oxide (TCO) films with a ZnO buffer layer showed better electrical and optical properties than those without a buffer layer. The crystal quality of the former was better than the latter, the electrical resistivity of the former is lower than the latter, and the transmittance of the former was also as high as that of the latter. The optimum buffer layer thickness with which the lowest resistivity of GZO/AZO/ZnO films was obtained was found to be 150 micro m. On the other hand it was found that there was little difference in electrical, and optical properties between AZO, GZO and GZO/AZO films with a ZnO buffer layer.

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We have investigated about limitation of line width in surface modification of polystyrene for nerve cell adhesion and neurite outgrowth by carbon negative-ion implantation. Carbon negative ions were implanted into polystyrene film on glass at 10 keV with 3 x 10^15 ions/cm^2 through a double-mask set with array of ridge shaped apertures gradually changing the width from 50 to 0 nm. The polystyrene film was prepared three times by spin coating with 7% PS in toluene at a speed of 1,000 rpm. After seeding on the modified SCPS sample, nerve-like cells of PC-12h were cultured with DMEM medium including 10% serum for 2 days in an incubator with 5%CO2 air flow at 37°C. Then, the cells were cultured for more 2 days in the incubator after replacing the serum DMEM medium to serum-free DMEM. As a result, the cell body adhered on the ion implanted area with the minimum width of 7 nm, and neurite outgrowth was observed also observed only on the ion implanted area m1til the width of 5 nm.

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Biocompatibility of silicone rubber sheet (SR) was improved by the carbon negative-ion implantation for the attachment of mesenchymal stem cells (MSC). The carbon negative ions were implanted at 10 keV and various ion doses from 0.01 - 10 (x10^15) ions/cm^2 through the micropattern mask with aperture slits of 50-micro m width for study of the selective attachment property. Contact angles of the modified SR at the same conditions without the micro-pattern mask were measured by water drop and air bubble. After 25-day in vitro culture of MSC from rat bone marrow on the implanted SR, the phase contrast micrographs showed the attachment of cells only on the stripe regions implanted with doses from 1 - 10 (x10^15) ions/cm^2. The good conditions for cell attachment are 3 and 10 (x10^15) ions/cm^2 of ion doses corresponding to the low contact angle, which is 69° and 61°. The fluorescence micrographs also confirmed that the position of cell nucleus and the actin filament on the implanted region at these implantation conditions. As implanted at low dose, no cell attached and cells very weakly attached.

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The adsorption properties of proteins such as laminin (LN), fibronectin (FN) and gelatin on the carbon negative-ion implanted silicone rubber sheet (SR) including their effects of these protein-coated modified SR on patterning nerve-cell culture were investigated. The implantation conditions were fixed at 3x10^15 ions/cm^2 and 10 keV. The concentrations of LN in PBS, FN in PBS and gelatin in de-ionized water (DIW) were 0.5-50, 0.5-10 and 5-10^3 micro g/ml, respectively. The adsorption properties of proteins on SR sheet implanted as a half moon shape were evaluated by XPS. After 4-day in vitro culture of the nerve-like cell of rat adrenal pheochromocytoma (PC12h) on the protein-coated surfaces of SR implanted through the micro-pattern mask with slits of 50-f..l,m width, the phase contrast micrographs show that the suitable protein for patterning the attachment of nerve cell was FN at 1 micro g/ml of concentration, corresponding to high ratio of nitrogen adsorption between implanted and unimplanted regions that was 1.9. As coated with 1 micro g/ml of LN, cells attached over all areas. While coating with 1 mg/ml of gelatin, no cell attached.

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We performed H+, H2+ and He+ ion-beam irradiation into biodegradable polymer sheets of Poly-L-lactic acid (PLLA) at an energy of 150 keV with a fluence of 1 x 10^15 ions/cm^2. The irradiated surface was investigated by means of FT-IR-ATR, Raman spectroscopy, and a contact angle meter. Ion-beam irradiated layer was exfoliated from the substrate in a water solution, and thin films were obtained. Next, H+, H2+ and He+ ion-beam irradiation was performed at an energy of 150 keV with a fluence of 1 x10^15 ions/cm^2 with a stainless-steel mask on the sample surface. We fixed the sheets to the bottom of a cell culture dish and seeded mouse fibroblast (L929) cells on the sample surface. These cells attached and spread on the micro-patterned domains, and the domains spontaneously exfoliated from the substrate. Consequently, micro-patterned cellular chips were obtained. These techniques and production methods are expected to apply to scaffolds, artificial organs and cell diagnosis tools.

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The surfaces of chitosan film were modified by He+, Ar+, Kr+, N2+ and O2+ beams and were characterized. An ion beam was irradiated at an energy level of 150 keV with fluences of 10^13, 10^14 and 10^15 ions/cm^2. The modified surfaces were characterized by Fourier-transform infrared (FT-IR) spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and contact angle measurement. The FT-IR measurement demonstrated that the original structure was destroyed and a new functional group was produced. The Raman spectroscopy revealed that an amorphous carbon phase was induced by ion beam. The XPS results indicate that the atomic percentage of carbon increases with ion fluences for each ion species. The average surface roughness (Ra) increased with the ion fluence when compared with the non-irradiated chitosan film surface. With a fluence of 10^15 ions/cm^2 all substrates displayed wettability of 70 to 72°.

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Recently, chitosan scaffolds with better biocompatibility have been required in various tissue-engineering applications. The aim of this work was to investigate the consequences of ion-beam irradiation on the biological properties of chitosan film, currently used in medical devices. The chitosan films were irradiated with He+, Ar+, Kr+, O2+ and N2+ at an energy of 150 keV and with fluences of 10^13, 10^14 and 10^15 ions/cm^2. Cell adhesion, proliferation and detachment were investigated on chitosan films modified by ion-beam irradiation. Cell culture experiments were carried out with L929 fibroblasts. After 24 h culturing, cells adhered better on each chitosan film modified by all ion beams with a fluence of 10^15 ions/cm^2 than on non-irradiated chitosan film. Cell proliferation tests after 48 h culturing indicated that the number of adhering and spreading cells on chitosan film irradiated at 10^15 ions/cm^2 was higher than on non-irradiated films (confirmed by cell adhesion tests). Also, cell attachment strength was increased after ion irradiation with a fluence of 10^15 ions/cm^2. Therefore, these results demonstrated that in-vitro cytocompatibi1ity of the chitosan film was improved by ion-beam irradiation.

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For a design of ideal structure in doped CeO2 solid electrolytes, micro-structures of M0.25Ce0.75O1.875 (M=Gd, Yb, Y) sintered bodies were characterized using Transmission Electron Microscopy. This micro-analysis indicates that micro-domain with ordered structure of oxygen vacancy is present in the sintered bodies. It is concluded that the micro-domain consists of a transition structure between fluorite and superstructure such as C-type rare earth structure. On the microanalysis data, we proposed our original idea of conduction mechanism in nano-hetero structured doped CeO2 solid electrolytes. In our idea, the space charge layer exists around micro-domains. This nano-structural feature is subtle, but it is concluded that the oxide ionic conductivity is conspicuously influenced by this subtle change in the grain.

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Pulsed electric current sintering (PECS) method has been examined for fabrication of dense doped CeO2 sintered bodies. But high pressure (1GPa) or long time post sintering (greater than 20h) is required in this method. To use this method for development of high quality solid electrolyte in solid oxide fuel cells, the simple PECS process without high pressure or long time post sintering should be developed. In the present study, we examined the influence of particle morphologies and heating rate on PECS behavior. M0.25Ce0.75O1.875 (M=Dy, Gd) powder was prepared by an ammonium carbonate co-precipitation method at 75°C. The relative density of doped CeO2 PECS specimen increased with an increase of heating rate. The densification behavior of PECS specimen was improved using round shaped particles. It is found that dense PECS specimen (greater than 93% of theoretical density) can be fabricated using nano-size round shaped particles and high heating rate more than 900°C/min.

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Performance of a fuel cell using Sn0.9In0.1P2O7 and Pt/C as the electrolyte and electrodes, respectively was evaluated in the temperature range of 150-300°C under unhumidified conditions. The cell performance was improved by forming an intermediate layer consisting of Sn0.9In0.1P2O7 and Pt/C catalyst powders at the interface between the electrolyte and cathode, which significantly reduced the cathode polarization. As a result, the peak power density reached 152 mW cm^-2 at 250°C using the 1.0-mm-thick electrolyte. The present fuel cell also showed high stability at low relative humidities (PH2O ~ 0.0075 atm) and 10% CO concentration. We also tested performance of a fuel cell using Mo2C-Zr02/C as the anode between 150 and 300°C. It was found that at 250°C or higher, the Mo2C-ZrO2/C anode showed a cell performance comparable to that of the Pt/C anode.

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An anode-supported single-chamber solid oxide fuel cell (SC-SOFCs), which consisted of a Ce0.9Gd0.1O1.95 electrolyte, a Ni-Ce0.8Sm0.2O1.9 (SDC) cermet anode, and a Sm0.5Sr0.5CoO3 cathode, was operated in a mixture feed of dimethly ether (DME), ethanol or butane and air at a furnace temperature of 300 °C. This SC-SOFC showed poorer performances for the DME and ethanol fuels than for the butane fuel, which resulted from low catalytic properties of the anode for the partial oxidation of DME and ethanol. An effective improvement was made by attaching Ru/SDC/Ni and Cu/Zn/Al catalyst layers for DME and ethanol, respectively, on the anode surface. As a result, peak power densities of 64 and 117 mW cm^-2 were obtained for DME and ethanol, respectively.

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This work investigates the effect (if any) on the conductivities of BaCe0.8Sm0.2O2.9 and BaCe0.8Y0.2O2.9 at ~500oC caused by differing microstructures over a range of dry and 'wet' atmospheres. Partial oxygen pressures ranged from 1- 10^-21 atm. Pellets of varying microstructures were prepared using conventional sintering with heating and cooling rates of 5-80°C min^-1 at temperatures of 1,300-1,550°C. Over the pO2 range, the main conductivity regions observed are a p-type contribution at 1-10^-4 atm and an n-type contribution at 10^-18 -10^-21 atm. The relationship between conductivity and microstructure in different atmospheres for BaCeY20 and BaCeSm20 can be slightly complicated. Generally, for BaCeY20, conductivity appears to increase with increasing heating rate or grain size up to a maximum (~15-20°C min^-1 or ~720-803nm), then decreases after that. For BaCe0.8Sm0.2O2.9 it is more difficult, as conductivity/ grain size or heating rate trends varying from atmosphere to atmosphere.

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Stainless steels are one of the most promising materials as bipolar plates for polymer electrolyte membrane fuel cells (PEFCs). In use of stainless steel bipolar plates, however, corrosion and corrosion induced degradation of cell performance are anticipated. In the present study, corrosion behavior of SUS 304 and 310S stainless steels was investigated through polarization tests in the simulated PEFC environment (0.05M Na2SO4 (pH 2.3) + 2 ppm F solution at 353 K), contact resistance measurement between steels and carbon diffusion layer and cell operation. XPS analysis was also carried out to compare the steel surfaces after polarization measurements and cell operation. The results indicated that passive current density for SUS 310S stainless steel in the simulated PEFC environments was lower than that for SUS 304 stainless steel, as expected from higher Cr content. Longer polarization of these steels decreased the passive current density but increased contact resistance due to thickening of the passive film. The cell voltage drops after 3.6 x 10^6 s operation were 14 mV for graphite, 22 mV for SUS 310S and 46 mV for SUS 304 steel. Apparent corrosion was recognized for SUS 304 stainless steel served for cathode.

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A Pt on nano-sized CeO2 particles which in turn are supported on carbon black (CB) was synthesized using co-impregnation method. The electrochemical activity of methanol oxidation reaction on the composite anode Pt-CeO2/CB was investigated using cyclic voltammetry and chronoamperometry experimentation. The onset potential of methanol oxidation reaction on the Pt-CeO2/CB anodes was shifted to a lower potential as compared with that on commercially available Pt-Ru/Carbon (C) alloy anode. In addition, the activation energy of the Pt-CeO2/CB anode was much lower than that of the Pt-Ru/C alloy anode at temperature between 28°C to 60°C. Moreover, the composite anode showed better stability of performance in a cycle test as compared with that of the Pt-Ru/C alloy anode. Importantly, the rare metal, Ru is not required in the present anode material and the amount of Pt required would be also significantly reduced. Based on those results, we expect that our composite anode will be one of promising new anode materials for fuel cell applications.

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Catalytic experiments were performed over atomized Ni3Al powder in the temperature range from 873 to 1223 K under the atmosphere of steam and methane (ratio of 1 ). The powder was treated by two kinds of two-step surface pretreatment before reaction. One is chemical treatment, acid leaching followed by alkali leaching. Another is steam treatment, oxidization in steam followed by reduction in hydrogen. It was found that the catalytic activity was significantly enhanced by both pretreatments, especially by the chemical treatment. The surface characterization of the pretreated powders revealed that the enhancement by the pretreatments was attributed to the formation of fine Ni particles on the surface.

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Pd-Cu alloy covered V-15Ni composite membranes have been prepared in this work. XRD, SEM and AES analysis were performed to characterize the composite membranes. Hydrogen permeation of the composite membrane under pure hydrogen and mixing gas with H2S impurity were studied, and the composition and thickness of Pd-Cu overlayers were optimized. It shows that the Pd60Cu40/V-15Ni composite membrane has higher permeability than other overlayer compositions. In the temperature range of 573~673K, the Pd60Cu40/V-15Ni composite membrane shows a good resistance to H2S impurity; when the temperature is lower than 573K, the effect of H2S impurity becomes more serious and the hydrogen permeability of Pd60Cu40/V-15Ni composite membrane decreases rapidly with increasing of H2S concentration.

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Metallic membranes play important roles in membrane reactor technology for on-site hydrogen production application. Pd and Pd-25Ag alloy membranes with the thickness of 2.5 micro m were successfully prepared on silicon support using microfabrication technology in this work. Silicon-supported Pd alloy membranes were characterized by in-situ hydrogen microscope within the temperature range of 423 ~ 673 K. The Si-supported Pd-25Ag alloy membrane showed excellent resistance to hydrogen-induced brittleness whereas the Si-supported Pd membrane had fractured upon hydrogenation-dehydrogenation cycle. Ni-supported Pd membrane in 2.5 micro m thick was also successfully prepared for permeation characterization. Hydrogen permeation of the Ni-support Pd membrane was carried out in a conventional gas permeation apparatus using pure hydrogen and gas mixture of hydrogen and 28.3 Vol.% CO2, respectively. Grain growth had occurred in the Ni-supported thin Pd membrane during hydrogen permeation. Surface resistance was significant and increased with the addition of CO2.

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A novel highly ordered three dimensional cage type mesoporous carbon nitride material (MCN-2 - CN nanocage) with very high surface area and pore volume has been prepared for the first time using three dimensional cage type mesoporous silica, SBA -16 as a template through a simple polymerization reaction between ethylenediamine and carbon tetrachloride. The material has been unambiguously characterized by various sophisticated techniques such as XRD, nitrogen adsorption, HRTEM, EELS, XPS, 13C DD-MAS, and FT-IR spectroscopy. The XRD result reveals that MCN-2 possesses three dimensional structure with a Im3m space group. The specific surface area and pore volume of MCN-2 are significantly higher as compared to those of the template and MCN-1. Because of the excellent textural characteristic and cage type three dimensional porous structure, we believe that the MCN-2 could offer great potential for the applications, such as catalytic supports, gas storage, lubricants, biomolecule adsorption and drug delivery.

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Highly ordered three dimensional large pore cage type mesoporous silica (KIT-6) has been synthesized using P123 and n-butanol as a structure directing agent and a co-solvent respectively and characterized by XRD and N2 adsorption. Adsorption of lysozyme on the above material has been studied as a model protein adsorption system and its adsorption isotherm has been fitted by Langmuir equation. The amount of lysozyme adsorbed over KIT-6 at the solution pH of 11, which is near the isoelectric point of lysozyme, is found to be 22.1 micro mol/. It has been found that the amount of lysozyme adsorbed over KIT-6 is much higher than that of MCM-48 which possesses three dimensional mesoporous structure with small mesopores.

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Novel microporous carbon with very high surface area has been synthesized for the first time using MCM-22 zeolite as a template. The specific surface area of the microporous carbon materials is much higher than that of its parent zeolite template. As the textural characteristics of the microporous carbon are excellent, we believe that the material will definitely find many applications in the field of adsorption and separation of small organic molecules such as amino acids, dyes and vitamins.

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N-doped mesoporous carbon with three dimensional and cage type pore structure has been synthesized for the first time via templating process using three dimensional cage type me so porous silica (KIT-6) and aniline as the template and the nitrogen source, respectively. Ammonium peroxy sulfate, NH4S2O8, was used to polymerize the aniline molecules. The obtained material has been unambiguously characterized by various sophisticated techniques such as powder X-ray diffraction, nitrogen adsorption measurement, CHN analysis, and x-ray photoelectron spectroscopy. The XRD results revealed that the material exhibits a well ordered three dimensional mesoporous structure. Nitrogen adsorption data indicates that the material possesses very high surface area and pore volume.

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The liquid-liquid interfacial precipitation method can produce C60 nanotubes with a length of the order of millimeters. The C60 nanotubes dried in air showed a Raman profile close to that of pristine C60. The C60 nanotubes are expected to be very useful to include various catalytic materials inside. The ultrasonic pulverization of the C60 nanotubes was examined in order to prepare short C60 nanotubes with open ends which make it easy to incorporate chemical substances. It was found that the ultrasonication of a few minutes is enough to prepare short C60 nanotubes with open ends.

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High yield (100%) of C60 fullerene nanotubes have been successfully produced by the liquid-liquid interfacial precipitation method in a small-scale experimental set-up. These nanotubes were. grown in the irradiated C60-saturated pyridine and isopropyl alcohol (IPA) system combined at different ratios (1:10, 1:9, 1:8, 1:6 C60-pyridine:IPA) and incubated at varying temperatures (15°C, 10°C, 5°C). Solutions irradiated under visible light (436 nm) produces higher yield of production and higher reproducibility compared with that illuminated with ultraviolet light (302 nm). The volume of nanotubes grown also increases with increasing ratio of C60-pyridine:IPA and decreasing temperature of incubation. Scanning electron microscopic observations show thinner nanotubes prepared with lower amount of IPA. At present, the process of scaling up the procedure to obtain gram quantities of nanotubes is under investigation. Such work will prove beneficial in obtaining more information on its physical and mechanical properties.

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The wall of as-prepared C60 nanotubes contains solvent molecules and the wall structure changes by drying. This change of wall structure was examined by Raman spectrometry. The structural change of C60 nanotubes by heating was also investigated using the Raman and TEM analyses. The C6o nanotubes heated at 300°C in vacuum turned to a disordered structure with amorphous carbon, and finely dispersed copper nanocrystals were observed by HRTEM, suggesting that copper worked as a catalyst to decompose the C60 nanotubes.

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Nanowhiskers and hexagonal nanocrystals of C60 have been successfully prepared using liquid - liquid interfacial precipitation method. C60 saturated benzene and carbon tetrachloride solution has been used for the interfacial precipitation reaction. Alcohols like methanol, ethanol, isopropyl alcohol, n-butanol, 2-butanol and n-pentanol have been used for the precipitation. The prepared C60 nanocrystalline solids from these disparate interface show different crystalline nature and assortment of morphologies. The optical microscopic image of the prepared hexagonal nanocrystals reveals clear change in the particle size for different alcohols. The effect of solvent on the crystal size has been studied by varying the amount of alcohol in the mixture. The Raman spectra of the prepared C60 nanowhiskers or hexagonal nanocrystals show polymerization of C60 molecule at the surface. The formation of tubular, non-tubular C60 nanowhiskers and C60 hexagonal nanocrystals has been confirmed using scanning electron microscopy and transmission electron microscopy.

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Catalytic properties of systems composed of copper loaded CeO2 and SnO2 were examined. Catalysts were prepared using a conventional impregnation method. After preparation the samples were calcined in oxygen respective reduced in hydrogen. Treatments were carried out at 400 oC resp. 300 oC for 2 hours. The amount of copper in prepared samples was 8 at. % in both cases. Morphology and particle size were observed using Scanning Electron Microscopy (SEM). Crystal phases were characterized by X-Ray Diffraction method (XRD). The CO oxidation reaction was performed in a flow micro-reactor in the mixture of He, O2 and CO, where the catalyst was deposited on a silicon oxide chip ensuring a very reliable catalyst temperature control. It can be expected that nano-structured copper loaded oxide catalysts could be used for removing CO produced in a wet reforming reaction for fuel cell applications.

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Recently, there has been a surge in the development of new electric energy sources in a wide variety fields. Examples of such energy sources are the fuel cell-, biomass-, plasma-, solar-, and wind-power generators, among others. In the present research, an attempt is made to apply the phytogenic potential as a new electric energy source, and the possibility to utilize this electric power without environmental disruption is examined. However, the maximum values of the potential were approximately 250 mV for most of the plants studied in the present experiments, and thus do not satisfy the criteria required for practical use, such as the drive voltage for an electronic circuit. For use in a practical application, it is, therefore, necessary to boost the potential value. Generally, however, it is difficult to boost the value of the potential. That is, the potential value is not boosted by simply connecting each phytogenic potential in series. The present paper describes how the potential value can be boosted by the use of special techniques, resulting in a successful boosted potential value of approximately 2.1 V. An electric double layer capacitor was charged with the electricity, and produced a luminescence of the light emission diode for approximately 3 minutes.

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Characteristics and microstructure of wood charcoal change dependently upon the carbonization conditions. Hinoki (Cypress, Chamaecy paris obtuse) was carbonized at 400°C, 600°C, 800°C and 1000°C for 1h in nitrogen gas flow. Charcoals were analyzed with adsorption isotherms of nitrogen, Fourier-transform infrared (FT-IR) spectroscopy, elemental analysis, electrical resistivity and Raman spectroscopy in order to investigate about the effect of the carbonization temperature on the structure of the charcoal. Increase of the carbonization temperature developed formation of micropores of the charcoal. From result of Raman spectroscopy, it was found that the crystal structure of the charcoal remarkably changed in the temperature range between 600°C and 800°C.

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Rice hull, which is one of the agricultural wastes in Japan, is required to be reused from a viewpoint of the recycling. The rice-hull silica carbon (RHSC) powder is prepared by mixing the rice hull particles with a phenol resin, and then carbonizing in nitrogen gas atmosphere at high temperatures. One of the effective utilization of the RHSC powder is as a filler for plastics and rubbers to improve the mechanical strength and the electrical conductivity. In this study, the improvement of bending strength of the RHSC/Polyphenylenesulfide (PPS) composites and electric conductivity of the RHSC/Etylene propylene diene methylene linkage (EPDM) composites were investigated by kneading the RHSC powder with PPS and EPDM, respectively. The bending strength was slightly improved and the conductivity was gradually improved with the amount of the RHSC powder. Especially, the dependence of the conductivity on the amount of the RHSC powder is utilizable for the production of antistatic polymers and rubbers.

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Rice Hull is one of the agricultural by-products, and is required to utilize as the industrial resources from a viewpoint of recycling. Previously, authors have proposed a manufacturing process of a carbon material made from the rice hull. The rice hull is impregnated with a phenol resin and is carbonized in a nitrogen gas atmosphere at 900°C. The carbon material is called rice-hull silica carbon (RHS carbon). The RHS carbon has the porous structure that is originated from the natural structure of the rice hull. In this study, the authors proposed an artificial procedure to control the porosity of the RHS. carbon. Then, the effect of the porosity on the mechanical and frictional properties was discussed. The friction coefficient is excellent in the porosity-controlled RHS carbon. It is expected to use the material for the application of the linear motion bearing and so on.

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Waste paper of postcards was used for the fabrication of woodceramics (WP-WCMs). To improve the humidity sensitivity, WP-WCMs were treated with H2SO4 or KOH after sintering or annealing, and their electrical impedance and humidity sensitivity were measured. Despite the decrease of impedance, the humidity sensitivity increased for WP-WCMs treated with KOH after annealing. The humidity sensitivity enhanced with the increase of KOH solution concentration. In other treatments both the humidity sensitivity and the impedance decreased. Consequently, in order to enhance the humidity sensitivity of WP-WCMs, the treatment with KOH after annealing is effective in improvement of humidity sensitivity.

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We have proposed an application of woodceramics sheet to electrode for Polymer Electrolyte Fuel Cell (PEFC). In order to apply the woodceramics sheet to the electrode, it is important to understand the fundamental properties such as electric resistivity. We made woodceramics sheet from a paper filter. The electric resistivity, bulk density and microstructure of the woodceramics sheet were investigated. The bulk density was measured to estimate the gas permeability, i.e., the permeability may go up with a decrease in the bulk density. In the investigation, we considered the influence of the degree K of impregnation of phenolic resin on these properties. It was confirmed that the bulk density increased with K although the resistivity decreased. We also analyzed the chemical compositions contained in the woodceramics sheet. As a result, the main component was carbon whose weight percentage was more than 90 wt%. There was a very small amount of impurities such as silicon and aluminum in the woodceramics sheet. This might mean that the woodceramics has desirable properties as the electrode of PEFC.

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We have proposed an application of woodceramics sheet to electrode for Polymer Electrolyte Fuel Cell (PEFC). The performance of the PEFC with woodceramics electrodes was experimentally investigated. The woodceramics electrode was made from a paper filter. It was confirmed that the amount of impurities in the woodceramics electrode was very small. The generated power of the PEFC with woodceramics electrodes was almost same as that of the PEFC with carbon paper electrodes. To estimate the influence of the degree K of impregnation of phenolic resin in the woodceramics electrode, we made several woodceramics electrodes with different K. The generated power of the electrode with K of 28.2 % was 0.34 mW/cm^2. It was highest among the electrodes made in this experiment. In case of the electrode with too large K, the output power may be low because of bad gas permeability. On the other hand, If the electrode has too small K, the output power may also · be low. That is because the mechanical strength may decrease with a decrease in K. This means that there may be the optimum K from the viewpoint of the output power.

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In this paper, a method of shock synthesis of diamond from apple wood ceramic .as a carbon source is presented. Experiments are carried out with a cylindrical compaction system using explosive. Apple wood ceramic, as a carbon source, is made by mixing the dried apple bagasse with phenol resin and carbonizing the mixture. The iron powder was used as catalysts. In these experiments, the pressure which acts on powder container is about 10 GPa. X-ray diffraction examination of the recovered powder, confirmed the conversion of carbon to diamond.

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