Indentation-induced stress distribution and pressure effect on the resistivity of YSZ

International audienceIonic conductivities measured under GPa-order high pressure provide various information about ion hopping mechanisms such as the activation volume (ΔV). Traditionally, anvil cells have been used for high-pressure measurements. We previously reported a new method for high-pressure impedance measurements, up to a few GPa, employing an indentation-induced local stress field. In this method, both mechanical and electrical (Young's modulus and high pressure impedance) properties can be obtained simultaneously. However, in this method, high pressures are induced only around the tip of the indenter, and such stress distribution should be considered for the estimation of ΔV accurately. In the present study, employing a finite element method (FEM) calculation, the stress distribution around the tip of the indenter, and effects of such GPa-order high pressures on the O2− ion conduction of Y2O3-doped zirconia (YSZ) are shown

Isolation and characterization of S. cerevisiae disruptants, which showed sensitive/resistant phenotype to ionizing radiation.

o analyze ionizing radiation resistance mechanism in S. cerevisiae, we > screened gamma-ray sensitive and resistant mutants by using a pool of > non-essential yeast gene deletion mutants (homozygous diploid mutants). > Almost half of the genes for sensitive candidates were classified into > Cell cycle, DNA processing functional categories of MIPS. To identify new > genes involved in DNA repair, we performed irradiation experiment by using > individual disruptants that are not known to be involved in the radiation > sensitivity, but none of them showed drastic sensitivity to gamma-ray. > Based on the irradiation experiments to the individual strains, we > isolated 14 candidates which showed reproducible resistant phenotype to > gamma-ray irradiation. We examined their responses to other DNA damaging > reagents. One of them showed a better growth phenotype compared to the > wild-type strain in the medium containing 1 mM of hydrogen peroxide and > another one showed a slight resistant phenotype to MMS. At the moment we > are examining the alteration of their genome-wide gene expression profiles第２０回IUBMB国際生化学・分子生物学会

Effects of TiO2 Particle Size On the Performance of Dye Sensitized Solar Cells Using Ionic Liquid Electrolytes

Different-sized nanocrystalline-TiO2 particles have been used for the optimization of photovoltaic er effects of dye-sensitized solar cells (DSCs) using an ionic-liquid (IL) electrolyte. Ru dye (Z907) was used for the IL-DSC optimization. The TiO2 nanoparticle sizes and the thickness of nanocrystalline- TiO2 electrodes ranged from 13 nm to 81 nm and 2 mu m to 23 mu m, respectively. The particle size of the nanocrystalline TiO2 film greatly a r ected the photovoltaic characteristics, particularly for the IL electrolyte due to limitation of the photocurrent by I-/I-3(-)-diffusion. The optimized electrode for IL-DSC had a 15 mu m thickness using a 27 nm diameter of nanocrystallineTiO(2) particles. In order to characterize the e r ect of the TiO2 particle size on the photovoltaic e r ects of IL-DSCs, a scanning electron micrograph (surface and cross section of nanoparticles), BET specific surface area analysis, pore-size distribution analysis, photocurrent transien