To achieve higher efficiency and output density in next generation fuel cells, lowering the irreversible losses associated with reaction and transport in the cell, especially the electrode overpotential, is inevitable. For this purpose, it is important to understand the processes involved in the electrode reaction. It is thus necessary to utilize simulations at different spatial and temporal scales as well as to collaborate with experimental observations. Multi-scale simulation approaches reported so far does not allow us to bridge atomistic level chemical reaction and micro-meter scale transport phenomena, which is necessary in simulating the fuel cell electrode reactions. As a part of such efforts, I will introduce the recent simulation efforts on the anode of SOFC anode. In collaborations with researchers from a variety of disciplines, improvement of anode kinetics is tackled from the perspectives of reaction at triple phase boundary and microstructure of porous anode.

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Photocatalytic hydrogen production has attracted attention as a clean solar hydrogen-generation system. High crystallinity and high surface area are important properties required for high efficiency photocatalysts. Two-dimensional semiconductor nanocrystals (nanosheets) prepared by exfoliation of layered metal oxides are ideal materials that can satisfy both of these requirements. In this study, we report a new approach to improve the photocatalytic activity of nanosheets. In general, a catalyst without co-catalyst loading has poor photocatalytic activity, while the Rh-doped oxide nanosheets exhibited high photocatalytic activity for H_2 production from a water/methanol system without co-catalyst loading. The quantum efficiency at 300 nm was 65%. The conductivity of the catalyst was decreased by doping, which indicates the RhO_6 units in the lattice of the nanosheet function as electron trap sites. The RhO_6 units in the nanosheet probably also act as reaction sites for H_2 evaluation.

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Silicon quantum dots (Si QDs) were fabricated and employed in poly(3-hexylthiophene-2,5-diyl) (P3HT) based organic photovoltaics for further enhancement of solar cell performance. Size controlled, mono-dispersed Si QDs were fabricated from silicon tetrachloride using very high frequency (70 MHz) non-thermal plasma reactor. Chlorine-terminated Si QDs was readily dispersed into specific type of organic solvent to form silicon inks. Si QD thin film was fabricated by solution process and integrated in bulk heterojunction (BHJ) P3HT/SiQD hybrid photovoltaics. Structure of hybrid photovoltaics and their performance in terms of short circuit current (I_<sc>), and open circuit voltage (V_<oc>) is first reported.

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Control of crystal orientation and diameter of vertically grown epitaxial Si nanowire arrays on Si substrate has been demonstrated using a combination of an anodic aluminum oxide (AAO) template and vapor - liquid - solid (VLS) growth using electrolessplated Au in AAO pores as a catalyst. The crystal orientation of the nanowire was investigated by transmission electron microscopy. A growth direction of the nanowire arrays was guided perpendicular to the surface of the substrate by the AAO template, and the crystal orientation of the nanowire arrays was selected using the single crystal Si substrate properly cut in desired orientation.

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Measurements of fine particles with micro and nano size in flow are important for manufacturing of electronic devices and so on. In many measurement devices, in-line measurement devices with a laser diode and two photo diodes is proposed. It is expected to be a general purpose and a low-cost device because it is simple. However, the measurement principle and measurable physics values has not yet been clear. The present study make it clear that the measurement principle and confirm measurable value in the device. For these objectives, not only the device but also two high speed video cameras are used in the experiment in order to confirm presence of a fine particle in flow and investigate scattering phenomena. From the experimental results, it is confirmed that signals from the photodiodes in the device, presence of a fine particle with size of 400 nm and generation of an interference pattern are synchronized.

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For transport-limited surface reaction, fluid flow transporting particles in a solution toward a reaction region is effective to enhance the reaction efficiency and rate. AC electrothermal (ET) flow, induced by property gradient due to temperature difference under electric field, is suited for the surface reaction enhancement. In this study, 3D flow field measurement was carried out to obtain ACET flow structure by micron-resolution particle image velocimetry (micro-PIV). A microfluidic device with an electrode having an inclined gap with 60 degrees respect to the streamwise direction was implemented. 3D velocity field is composed based on orthogonal 2D velocity fields by the observations of particle movement from side- and bottom-view. As a result, 3D flow of ACET was successfully measured. The results indicate that more effective flow concentrating particles would be available.

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The molecular tagging velocimetry (MTV) is applied to measure the velocity fluctuation in a supersonic micro jet issuing from the two-dimensional Laval nozzle whose height is 500μm at the exit. This velocimetry uses the forth harmonic of a Nd:YAG laser (266nm) as a light source to excite the acetone molecules seeded in the flow, and fluorescence images are captured by a CCD camera 300ns after the laser illumination. The distribution of root-mean-square (RMS) of velocity fluctuation is obtained from these images. The distribution represents well the characteristics of the turbulent micro jet although unreasonable RMS values due to low fluorescence intensity are recognized around the jet. The distribution of single-time two-point spatial correlations is also obtained from the measured velocity fluctuations and this distribution reveals that the micro jet fluctuates in a flapping mode.

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Two types of MEMS thermal sensors were developed to investigate heat transfer mechanisms of pool boiling and flow boiling in minichannel. In pool boiling experiment, local and fast heat transfer phenomena under a bubble were measured. The heat transfer analysis using the measured temperature indicated the contribution of wall heat transfer to bubble growth is almost constant value of 50%. The local wall temperature under a bubble growing in the minichannel also showed evaporation of the microlayer. It was shown by the heat transfer analysis that initial thickness of the microlayer in flow boiling in the minichannel has a few microns thickness and increases with velocity of bubble forefront.

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LiCoO_2 (LCO) crystal layers were fabricated on cobalt-coated aluminum substrate by flux coating method at holding temperature of 500℃. Metallic cobalt layer was used as a solute, and LiNO_3 was used as both flux and solute. Metallic cobalt layer was used as a solute. The XRD pattern of the sample showed that LCO was generated on the aluminum substrate without any byproducts after flux coating. The LCO crystal layers consisted of a number of plate-like crystals, which almost grew vertically to the substrate. When the holding temperature was increased at 600℃, Al_9Co_2 was generated as a byproduct. The thickness of the cobalt metal layer decreased by increasing the holding time, whereas the obtained crystal phase was not affected.

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We have investigated the crystallization process of YBa_2Cu_3O_7 (YBCO) films with BaZrO_3 (BZO) to enhance critical current density, Jc. In order to control and optimize the microstructures of YBCO films during the crystallization process, the precursor films were heated up to 600℃ for 0, 60, 180, 540 min before YBCO crystallization. From XRD results, the peak intensity of BZO (110) was found increased with the film kept 600℃ for the longer period, which suggested that BZO was crystallized lower than at 600℃. Moreover, the film kept at 600℃ for 180 min showed improved Jc characteristics of 7.77×10^4 A/cm^2 at 3 T (B//c) at 77.3 K, which was 2.5 times higher than the film without keeping as 3.04×10^4 A/cm^2. These results suggest that microstructures and Jc characteristics could be improved greatly by controlling the heat treatment during the crystallization process.

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Direct electron transfer (DET) from biomolecules to electrode is a process without electron-mediator, thus superior selectivity and sensitivity is expected in order to monitor electron transfer between electrode and biomolecules without any mediator interference. However, DET occur hard because a redox center which is an electron active center of proteins such as enzymes is buried deep. So, unique electrode nanostructure to reach the redox center is a critical factor. Here we have systematically investigated terms for DET using various nanofiliformed electrod morphology and enzyme concentrations. It is pointed out that the reaction-site is below 100 nm, the ration amounts of adsorbed enzyme per surface area are below 1.0 are contributed to the DET. As a great application, we have developed a biosensor monitoring the hydrogen peroxide (H_2O_2) detecting capability from peroxidase directly. The fabricated HRP/nTOF/Ti-electrodes observed the catalytic current value was linear according to increase in the concentration of H_2O_2 up to 100 μM, which indicates a good potential for H_2O_2 biosensor.

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Gold nanorods have an absorption band at the near-infrared region and convert the absorbed light energy into heat, so-called photothermal effect. In this study, we constructed controlled release system of drugs triggered by light irradiation. Double-stranded DNA was modified on gold nanorods, and near infrared light was then illuminated. The gold nanorods were heated by the photothermal effect, and single-stranded DNA was released from the gold surface. The DNA release was also observed in vivo. Furthermore, we showed that the photothermal effect enhanced permeability of stratum conium layer of skin. Combination of gold nanorods and near infrared light irradiation is expected as a novel technique for transdermal protein delivery system.

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Recently practical micro/nano devices using nanomaterials such as nanoparticles and nanowires have actively developed in various fields including nanophotonics and nanoelectronics. Manipulation of nanowires is indispensable for constructing the microdevices. Here we demonstrate the rotation and translation of a silver nanowire by an optical vortex. In our method, a silver nanowire can be grasped and rotated by repulsive force of an optical vortex. In addition, by switching the direction of azimuthal phase shift repetitively, a silver nanowire can be aligned in any direction. By moving the stage supporting a sample, the nanowire can be also translated to the desired position with the fixed posture. The manipulation technique using an optical vortex will be a powerful tool for manipulating and assembling various kinds of nanowires.

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In this article, the fabrication of SON (Silicon on Nothing) nanowires by means of FIB (Focused Ion Beam) fabrication and the size effect on the mechanical properties are described. We designed the on-chip tensile testing device, which consists of a nanowire specimen, an electrostatic actuator for stretching the specimen, and two sets of capacitance sensors for measuring the tensile displacement. A theoretical resolution of 1 nm in tensile displacement measurement was achieved. The uniaxial tensile force was derived from the spring constant of suspended beams with theoretical resolution of 15 nN. After fabricating SON nanowire specimen using FIB, the tensile test was carried out. The Young's modulus was measured to be 168.8 GPa, which is close to the ideal value of SCS (001)[110]. The tensile strength was 8.3 GPa, indicating that there was a size effect on the strength.

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Aiming to realize the thermal-driven actuators in nanometer scale, we have fabricated a bimetal-type nanocomponent consisting of a boron nitride nanotube (BNNT) with platinum (Pt). Previous studies suggested that the high rigidity of the BNNT must work as the resistance to the thermal deformation of this actuator. In this study, we performed the Ar ion etching of individual Pt/BNNT bicomponents in order to control the strength of the mechanical strength of entire system, and the deformation with elevating temperature was observed by a transmission electron microscope (TEM). As the result, it was found that Pt/BNNT partially etched by the ion irradiation showed bending deformation at 〜100℃ due to the thermal expansion of Pt.

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Nanomechanical tuning forks were fabricated using focused-ion-beam chemical vapor deposition, and their vibration characteristics were evaluated theoretically and experimentally. The tuning forks were modeled by a beam connected to torsional springs to calculate resonant frequencies. The vibration characteristics of the tuning forks were measured with an optical instrument under vacuum of 10 Pa and the ambient pressure. For tuning forks vibrating in the anti-phase mode, the quality factors measured under the vacuum condition were as much as twice as high as those of the tuning forks vibrating in the in-phase mode. In contrast, under the ambient pressure, the quality factors of the tuning forks vibrating in the in-phase mode were higher than those of the tuning forks vibrating in the anti-phase mode. The in-phase mode is considered to reduce the viscous damping caused by the surrounding air. The result indicates that nanomechanical resonators can have high quality factors under the ambient pressure when their components are operated to vibrate in phase.

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We have developed the fabrication process of planer-type thermoelectric module by application of ink-jet technique. Both p- and n-type thermoelectric inks were prepared by the dispersion of Bi-Te thermoelectric material particles into solvent. The ink-jet printed planer-type thermoelectric module with five p-n pairs demonstrates satisfactory thermopower by 340μV/K per one-pair. This thermopower is nearly corresponding to the values of commercial bulk Bi-Te thermoelectric materials. We have also succeeded the printing of small size thermoelectric module and module-printing on a flexible substrate. These results indicate that the ink-jet technique is a breakthrough for the fabrication of micro-sized thermoelectric modules for energy-harvesting.

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In order to develop highly efficient energy materials, especially thermoelectric thin film, in this study we developed and investigated a thin film growth mechanism that produced thin films with "new functions". We achieved this by integrating the control of interface technology by using an advanced thin film growth process that uses nano-technology, controlling the growth of interface, controlling the micro-structures of the films, and using multilayer technology.

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A concept of flexible thermoelectric (TE) device was proposed. The proposed device consists of TE thin films and flexible substrates that composed of low- and high-thermal conductivity materials such as resin and metal. The structure of the substrate enables the device to generate electricity by temperature difference at the TE thin films. We confirmed the concept by computer simulation using Finite Element Method. The simulation indicated that the proposed device can generate electricity and output power from the device was estimated using the calculated temperature distribution, material parameters, and dimensions of the device. We also fabricated the flexible TE device. TE materials were deposited on a flexible substrate composed of polyimide and copper sheets. Output voltage and electrical power from the device were measured at room temperature by applying temperature difference to the device. The measured output characteristics were in good agreement with the estimated ones.

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Thermoelectric micro devices with synergetic combination of catalytic combustion and thermoelectric conversion are developed. Thermoelectric gas sensor (TGS) has developed and aimed at the applications to the hydrogen safety and human breath analysis. The TGS has unique gas sensing performance such as wide range detection, gas selectivity and immunity to humidity. Planar type thermopile micro generator devices of thin-film couples of BiSbTe and Pt and catalytic combustor has been developed. 11 thermopiles are connected in series as an array and Pt-loaded alumina ceramic catalyst was deposited on the thermopile as a combustor layer. The combustion and TE performance of the generator was investigated flowing 3 v/v% hydrogen in air. The temperature gradient of eleven thermopiles developed between the hot and cold junctions of thermopiles was 50.6 K, and 1.9 μW of power was generated.

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In this paper, we report the observation of single-stranded DNA (ssDNA) near a glass surface. Oligonucleotide was labeled by tetramethylrhodamine in order to observe the motion of ssDNA under TIRF (Total Internal Reflection Fluorescent) microscopy. The diffusion coefficient of ssDNA was estimated by analyzing the observed images. The diffusion coefficient was compared with a previous report.

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Actin filaments play important roles in many kinds of cellular function by interacting with hundreds of actin binding proteins (ABP). Actin filament is dynamically changed by influence of biochemical and mechanical factors. It is important to measure actin filament and ABP interactions quantitatively in order to investigate actin filament dynamics. In this study, we probe the interaction between α-actinin and actin filament using an AFM and dynamic force spectroscopy (DFS). The dissociation constant of α-actinin and actin filaments binding was estimated by the DFS analysis, and the value was in good agreement with previously reported one which was obtained by an optical tweezer. We proposed that our method would be useful for the interaction measurement of actin filaments and many kinds of binding proteins, and could be further applied to the actin dynamics measurement.

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Bio molecular imaging is important to clarify cellular functions. Cathodoluminescence (CL) is light emission from the materials excited by accelerated electron beam, and CL microscopy has the potential to enable color imaging of individual biomolecular distributions with using immunolabeling at high spatial resolution. Because of electron beam excitation the spatial resolution reaches about 10 nm. In this study, we demonstrated CL imaging for cells using rare-earth doped nanophosphors at high spatial resolution.

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In order to realize spatial and temporal imaging of cellular functions of single living cells, we have been developing a newly designed probe for atomic force microscope (AFM), named "bioprobe", which is integrated with a hollow silicon dioxide (SiO_2) nanoneedle. By employing our newly developed process, bioprobes, which are fully integrated a fluidic microchannel embedded into a silicon (Si) cantilever beam structure, were successfully fabricated. We also proposed a novel intracellular delivery method based on electrokinetically driven flow. Preliminary ejection tests revealed the capability of handling an extremely small volume of liquid with good controllability.

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We propose fabrication process of micronozzle array with flat tip and establish important part of the process. We demonstrate fabrication of through holes in a Si substrate. Fabricated holes were enlarged by about 3 μm from pattern on mask. Flatness of the tip region was preserved after the etching process. Height of nozzle was controlled by adjusting time of deep silicon etching. Cells were captured and released with a hole-substrate. A cell was captured with a φ5.5 μm nozzle at -50 kPa. With increasing hole diameter, cell internal entry rate increased. We succeeded in release of a cell after cell capture.

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In this study, we investigated the trans-membrane dynamics of macromolecules by real-time visualization in on-chip electroporation using field focusing. The device for on-chip electroporation consisted of two parallel microchannels that are connected through a micro-orifice for field focusing and cell trapping. The micro-orifice embedded in a vertical wall of the microchannel was 4.04 μm in width, 3.68 μm in height and 4.0 μm in length. By measuring ionic current through the micro-orifice, we evaluated electrical characteristics of the device. A HeLa cell was trapped at the micro-orifice by aspiration. Then, pulsed voltage, which was 10 V high and 1 ms long, was applied to electrodes located across the micro-orifice. The change of the fluorescence intensities indicated the successful pore formation. By analyzing the time course data of the fluorescence intensity, we discussed the detailed mass transfer through the cell membrane.

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We have focused a glow discharge in liquid, which is called solution plasma, as a novel material synthesis method. The high energy field, solution plasma, formed in liquid causes to various reactions and it makes possible to fabricate novel materials such as nanoclusters as well as carbon materials. Thus, it can modify surface of the powder such as carbon materials. Since nanoclusters show different properties from bulk material, novel catalyst may be found in nanoclusters. Carbon material is useful for battery electrode. Surface modified filler will be important for composite material. In this matter, solution plasma process has a big possibility as novel material synthesis.

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One-dimensional NiO and CeO_2 crystals were successfully grown by the cooling of chloride flux. NiCl_2・6H_2O or CeCl_3・nH_2O powders were used as the solute, and LiCl and KCl were chosen as the flux. The mixtures were heated to 700-900℃ for 10 h, and then cooled to 350℃ at rate of 200℃-h^<-1>. The NiO crystals had average sizes up to 481×3.65 μm. The morphology of the CeO_2 crystals clearly depended on the growth conditions, such as the holding temperature and Ce concentration. From X-ray diffraction pattern, the one-dimensional NiO and CeO_2 crystals elongated in the <100> directions.

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Cytochrome c is one of the most extensively studied proteins because of their unique functionalities including electron transfer (ET). ET reaction of cytochrome c is slow, thus direct electron transfer (DET) reaction between proteins and electrodes is rarely observed. We have invented slab optical waveguide (SOWG) spectroscopy by which in situ observation of UV-vis. absorption spectra from adsorbed molecules on solid/liquid interfaces under monolayer coverage can be performed. As a great advantage, SOWG spectral change can bring us molecular functionality. In this presentation, we will report, we will report DET reaction of cytochrome c adsorbed on ITO electrode by SOWG spectral change due to electrode potential scan, and that cytochrome c adsorbed on ITO electrodes kept ET activity. without addition of any promoters or mediators, and surface modification.

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The conversion of dinitrogen to ammonia under mild conditions is of great importance. The redox property of dinitrogen in P_<14>NTf_2 ionic liquid containing Cp_2TiCl_2 under dinitrogen atmosphere was studied, and the effect of coordination of ^-NTf_2 anion to Cp_2TiCl_2 was discussed. Electrolysis of dinitrogen in water divided with Nafion ^[○!R]212 with this system showed the generation of ammonia. Controlled-potential electrolysis of dinitrogen to ammonia at -2.65 V (vs. Fc/Fc^+) was carried out, the maximum current efficiency being 4.68 %.

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In this paper, we report on a method to measure the strain in an individual single -walled carbon nanotube under tensile test by using micro Raman spectroscopy. Raman spectroscopy has many advantages for measuring strain of materials. The measurement is quick, non-destructive, and no special preparation required. Since the Raman G-band spectrum of SWCNT shifts down linearly against the tensile strain, we measured the strain in SWCNT loaded by a MEMS tensile testing device with a thermal actuator. As the result, we observed a down shift of the G-band, which corresponds to 0.15〜1.35% in strain. We confirmed the strain is successfully applied to SWCNT using the device.

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We evaluated compositional dependence of piezoelectric and dielectric properties of Pb(Mg_<1/3>Nb_<2/3>)_<1-x>Ti_x(O_3(PMN-PT) films by using combinatorial sputtering method. Compositional gradient PMN-PT films were deposited on Pt/Ti/Si substrates by using multi-target sputtering. Piezoelectric and dielectric properties of PMN-PT films were evaluated as a function of composition x in Pb(Mg_<1/3>Nb_<2/3>)_<1-x>Ti_xO_3. Relative dielectric constant and remnant polarization (P_r) increased with decreasing PT ratio.

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In order to develop a high-performance thermoelectric material, it is of great importance to find the way to control three thermoelectric properties: Seebeck coefficient S, electrical conductivity σ, and thermal conductivity κ. Our recent studies revealed that Seebeck coefficient, electrical conductivity, and electron thermal conductivity can be quantitatively estimated once the spectral conductivity and chemical potential are determined. We also found that these electron transport properties are separately controlled by knowing the fact that the energy range of electrons for these properties are different from the others. It was also revealed that the dimensionless figure of merit ZT=S^2σT/κ, which is generally used as a measure for performance of thermoelectric devices, is less sensitively affected by the scattering of electrons. These facts strongly suggest that the thermoelectric properties are capable of being optimized for thermoelectric materials by using the micro and nano-structures, provided that these characteristic structures in nano and micro-scale cause significant variation in electronic structure rather than in the scattering processes.

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Improving thermoelectric energy conversion requires high power factor and low lattice thermal conductivity. Although first-principles-based calculations for power factor have been carried out extensively, there are few studies on lattice thermal conductivity based on first-principles. In this work, to accurately evaluate heat conduction, we have performed the first-principles-based anharmonic lattice dynamics for single-crystalline lead-telluride and magnesium-silicide that are leading thermoelectric materials in intermediate-high temperature regions. Subsequently, we have performed the molecular dynamics using anharmonic potentials obtained by first-principles for lead-chalcogenides alloyed crystal. It is demonstrated that the systematic first-principles-based calculations deliver accurate lattice thermal conductivities of single-crystals as well as alloyed crystals.

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Thermoelectric power of graphene nanoribbons (GNRs) has been theoretically investigated by first-principles simulation based on the density-functional theory combined with non-equilibrium Green's function method. The thermoelectric power of GNRs strongly depends on their edge structure and ribbon width. We clarified the condition for the ribbon structure to enhance the thermoelectric power of GNRs. In addition, we found that the thermoelectric power of zigzag-edged GNRs shows peculiar energy dependence originating from edge-localized electronic states with energy near the Fermi level. These results can be explained in terms of the energy-band structure of GNRs.

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We have prepared Al doped ZnO (AZO) thin films for thermoelectric application by Pulsed Laser Deposition (PLD) technique on STO substrates at various deposition temperatures (T_<dep>=400C, 500C, 600C). The thermoelectric properties of AZO thin films were studied in temperature range 300 K-600 K. The electrical conductivity was measured as 3×10^3 S/cm at 300 K using four-probe technique. The value of Seebeck coefficient was in the range of -95μV/K〜-244μV/K and Thermal conductivity at 300 K for thin films was 0.12 W/mK〜2.0 W/mK. We report for first time high value of figure of merit 0.54 at 300 K for AZO thin films. The overall thermoelectric performance of AZO this films is strongly enhanced in comparison with bulk pellets.

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Conducting polymers, such as polyaniline (PANI), polypyrrole, and polythiophene, have several attractive features for use as thermoelectric materials because of the thermal conductivity much lower than that of inorganic thermoelectric materials as well as their potential low cost due to available resources, easy synthesis, and easy processing into a versatile form. We report the thermoelectric properties of the (±)-10-camphorsulfonic acid (CSA) doped PANI films and poly (3,4-ethylenedioxythiophene)(PEDOT)-polystyrene sulphonic acid (PSS) films. We also evaluate the important properties, flexibility, durability, and thermal stability, for practical use of these conductive polymer films as thermoelectric materials.

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An electroporation device comprising an orifice sheet with regularly spaced micron size orifices for electric field constriction was developed and utilized to electropolate adherent HeLa cells constitutively expressing Fucci; a fluorescent cell-cycle reporter. Cells seeded overnight on the orifice sheet were successfully electroporated with GFP plasmid and a mixture plasmid consisting of Yamanaka factors (oct3/4, Sox2, Klf4 and cMyc), and the influence of the introduced factors on the cell cycle was examined. Preliminary results of cell cycle monitoring by time-lapse microscopy point to the possibility of cell cycle control by Yamanaka factors, as suggested by the observed attenuation of cell cycle progression following electroporation of Fucci HeLa cells with Yamanaka factors. Electroporation of GFP plasmid alone, however, did not have notable effect on cell cycle progression. Further research is underway to ascertain the connection between the observed cell cycle control and reprogramming efficiency.

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Hypoxic microenvironment affects cell fate, and regulates various physiological and pathological phenomena. We designed a microfluidic device to control oxygen tension for three-dimensional cell culture. A polycarbonate (PC) film was embedded in the device to overcome oxygen diffusion from the top surface. Numerical simulations were performed to investigate changes of oxygen tension upon varying the media and gas flow rates. In addition, oxygen tension created based on the computational optimization was validated by using a ruthenium-coated oxygen-sensing glass cover slip. The computational results revealed that there was the optimum combination of the flow rates of media and gas to control oxygen tension, showing establishments of a low uniform oxygen tension (<3%) or an oxygen gradient. The experimental results agreed well with the corresponding computational results.

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Cell separation by its size without giving damage is effective to further cell process in cell diagnosis and tissue engineering. We developed a twisted micro-channel which separated cells by its size with the help of the difference of the drag force. Our experimental results showed that the 3 dimensional sheath-flow which collected cells in the center of the channel was realized.

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Aiming at the use in low-invasive medical treatments, a tungsten microneedle was fabricated by electrochemically etching a thin wire having 100 μm in diameter. A hole was fabricated on the tungsten needle by electrochemically etching a groove and making a lid on it by chemical vapor deposition of Parylene, followed by sputtering of tungsten. Both of delivering air and aspirating water were successfully achieved, showing that the fabricated needle is surely hollow.

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Brain-Machine Interface (BMI), which is a system interacting between our brains and machines, can be applied in various ways such as communication tools for serious handicapped person, entertainment tools. We demonstrated the fabrication of polymer micro-needle electrodes that may be applicable as flexible electrodes in BMI. For this application, conductive layer of needle surface must be protected from peeling off during the insertion. Thus, we coated the electrodes with a nanoporous parylene film after a silver film was deposited. We experimentally verified when the amount of the parylene dimer was 75 mg, the conductive membrane was successfully protected while maintaining conductivity.

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Chemo-mechanical energy conversion of an organic engine in the autonomous drug release system was improved by modifying its physical structure. The organic engine was fabricated by separating a cylindrical cell into a top-cell (gas-phase) and a bottom-cell (liquid-phase) by glucose oxidase enzyme immobilized membrane and, it generates decompression autonomously by catalysis of glucose oxidation. Therefore, in order to increase decompression rate, methods to enlarge area of the enzyme membrane per volume of the gas chamber were proposed and evaluated. As a result, two times higher output that can make the system possible to actuate on low glucose concentration close to blood sugar was obtained.

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Tissue vulnerability diagnosis of atherosclerotic plaques has been being required, because the rupture of unstable plaque on coronary artery should cause acute coronary syndromes. 3-Dimensional Optical Coherence Straingraphy (3D-OCSA) is proposed, which can visualize tissue mechanical information, e.g. strain distribution, from speckle deformation between synthetic 3-dementional images obtained by Optical Coherence Tomography. This is basically constructed by Recursive 3-dementional FFT Cross-correlation as well as Image Deformation technique which take account of linear deformation of interrogation volume. Finally Weighted Moving Least Square Method can provide tomographic tissue strain distribution with high resolution. In this study, 3D-OCSA was ex vivo applied to plaque lesions in WHHL rabbit aorta, according to the validation result using artificial phantoms of atherosclerotic plaque. Consequently, Residual negative strain distributions identified the accumulation of lipid tissue having low elastic modulus, which was qualitatively analogous to histological images and FEM simulation results. It was concluded that 3D-OCSA could be highly effective to clinical assessment of atherosclerosis as "Micro Mechanical Biopsy".

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In this study, we report on a blood pressure pulse wave device with an extension mechanism for high-accuracy measurement. This device consists of a force sensor for blood pressure and the extension mechanism with a 2-axis force sensor. The sizes of the force sensor for blood pressure and the extension mechanism are 12×12 mm^2 and 10×10 mm^2, respectively. The pushing force and the extension force of skin extension can be measured by a 2-axis force sensor of the extension mechanism. We measured blood pressure pulse wave by the prototype device, and calculate the S/N ratio of blood pressure pulse wave. When the extension force is 23 kPa and the pushing force is 8.5 kPa, S/N ratio was improved by 43% compared to without the extension mechanism. Since the heterogeneous of the subcutaneous tissue was reduced by the extension mechanism, S/N ratio of blood pressure pulse wave increases.

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We fabricated piezoelectric MEMS energy harvesters of PZT thin films on the microfabricated stainless steel cantilevers. The 2.5-μm-thick PZT thin films were directly deposited by RF-magnetron sputtering. Direct deposition of PZT thin films can reduces the complexity of the fabrication process of the piezoelectric MEMS energy harvesters. Furthermore, because of strong fracture toughness of stainless steel, the thickness of the cantilevers could be as thin as 30 μm. We confirmed strong diffraction peaks corresponding to pervskite PZT without a pyrochlore phase by XRD, which indicates that the polycrystalline PZT films with pervskite structures were grown on stainless steel cantilevers. We evaluated the power generation performance of the unimorph cantilever (7.5 mm-long, 5.0 mm-wide) with the tip mass of 2.5×10^<-5> kg. The averaged output power reached 6.0 μW at 10 m/s^2 and a low resonant frequency of 367 Hz.

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In this paper, we presented a measurement of power output versus acceleration with a data logger. The vibration energy harvester consists of a Si grid, a vibration mass, which has a charged electret film, and a cover glass. The data logger can measure voltage outputs, acceleration, temperature, humidity, and electrocardiogram (ECG). Accelerations and output voltages from the harvester were measured by 10 bit ADC (analog-to-digital converter) and the sampling frequency was 125 Hz. The power output at different accelerations on modal thruster is calculated by the output voltage from the harvester and the 20 MΩ load resistance. The power output was proportional to acceleration and the maximum generated power was 17.3 nW. The generated power worn on ankle while walking was 2.1 nW.

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