• Plasma sterilization has been developed as an alternative sterilization method due to its chemical activity, operation at low temperature and atmospheric pressure, low power consumption, low cost and safety. We have studied a mechanism of chemical species generation and transport in a plasma flow and, the sterilization efficacy and mechanism for several plasma sources at atmospheric pressure, such as a microwave plasma flow, a dielectric barrier discharge in a tube and a water vapor plasma flow. We already clarified that the damages of outer membrane and destructions of the cytoplasmic membrane of Escherichia coli by exposure to the microwave plasma flow. Fig. 1 shows the effect of plasma exposure on the E. coli. When the E. coli was exposed to the plasma, the height of the E. coli decreased and the potassium leakage of cytoplasmic material increased. For sterilization in a tube, we also clarified that an induced flow in the narrow tube by DBD transports chemical species and sterilize the whole inside surface of a tube as shown in Fig. 2. We hope to conduct collaborative research with a willing company for a practical application of this technology in industry.

• This group is engaged in basic and applied researches of "hydrides" for practical use in hydrogen energy system. The main subject is the exploration of advanced hydrogen storage materials which support hydrogen energy technologies such as fuel cells. Currently, we synthesize a wide variety of novel hydrides composed of lightweight metals with specific nano-structures using advanced techniques for crystal and electronic structure analyses. In addition to the hydrogen storage, we develop the wide research fields related to hydrides, such as fast lithium ionic conductors.

Besides the contributions in industrial progress through the material development for future hydrogen energy system and next-generation secondary battery, we positively provide technical assistance to organizations and companies concerned about our findings.

• Our goal is "bio-inspired engineering" to create new functions that exhibit functions beyond the nature systems by learning from their superior functions and incorporating them into creating materials and devices. For example, the development of surface treatment and adhesives learned from mussels, the development of anti-biofouling substrates learned from pitcher plants, the design of non-platinum catalysts for highly active fuel cells (hydrogen, enzymes, microbes, etc.) learned from hemoglobin, and needle-type biosensors learned from biological needles.

Based on electrochemistry and polymer chemistry, I provide technologies and expertise in the energy, biotechnology, and electrical and electronic fields, including metal-air batteries, fuel cells, surface treatment, adhesion, biosensors, etc.

• 　Using laser fabrication, we are developing techniques to enhance material surface properties and functionality. For example, to create a functional interface, we aim to clarify, by way of simulation and experimentation, the phenomenon that occurs when the surface of a material is irradiated using a laser beam.
• 　We expect that the results of our research will be widely applicable, including biomedical devices.
• ■　Creation of biocompatible surfaces
• 　Materials used for artificial organs, vessels, and other bio-implants require excellent tissue and cell biocompatibility. Therefore, we are exploring the creation of biocompatible surfaces using a new laser irradiation process in this study.
• 　We have succeeded in imparting a biologically active function to titanium-based materials by applying the laser irradiation technique. When such a material that has a biologically active function is inserted in a living body, hydroxyapatite (the principal constituent of bones and teeth) precipitates on the surface. Using the laser irradiation technique, we can manufacture bone-adherent implants, and we envisage their application to artificial joints or dental implants.
• 　This research aims to discover such breakthrough solutions for biomedical applications using the laser irradiation technique.

• Recently, many tunnel magnetoresistance devices with high magnetoresistance effect are reported. These are expected to be applied to high sensitive magnetic sensors. There are many magnetic sensors with variety of the mechanism, in order to meet the demand of the very wide range of sensing magnetic field. However, there is no magnetic sensor which has high sensitivity, easy to use, operation at room temperature and low cost. Only a magnetic sensor with tunnel magnetoresistance devices can satisfy all the demand in principle. As the device has very wide range of the sensing magnetic field, it can be designed for any demand to the sensors.

For example, this device can sense a bio-magnetic field easily at room temperature, so that it could be replaced SQUID device, which is popular now but is very expensive and not easy to use personally. Therefore, by using this device, we expect we can conduct effective collaborative research in medical field.