Mass wasting process at the surface of the Sangun metamorphic rocks in Kaminishigawa area, Asahi-machi, Okayama Prefecture.

The relation among microstructures, weathering and mass wasting of the Sangun metamorphic rocks in the Kaminishigawa area, Asahi-machi, Okayama Prefecture, was studied. Three stages of penetrative planar structures are recognized; S1 schistosity, S2 crenulation cleavage and S3 crenulation cleavage. The S2 cleavage is the most commonly observed structure. The deree of weathering is divided into two classes on the base of appearance; slightly weathered and highly weathered rock. The three types of mass wasting are also observed in this area; creep, slide and flow type. The S2 cleavage are bent and broken into several blocks in the creep type. The slide type is of rock block sliding along S2 cleavage. The flow type is of debris flow. The type of mass wasting, degree of weathering, and topographic position are mutually related : the slightly weathered rock and creep type are observed on the steep slope at the foot of the mountains; slightly weathered rock and slide type on the steep slope of the mountainside; highly weathered rock and flow type on the gentle slope near the top of the mountains

Inter-annual variation in CH4 efflux and the associated processes with reference to delta-13C-, delta-D-CH4 at the Lowland of Indigirka River in Northeastern Siberia

第6回極域科学シンポジウム分野横断セッション：[IA] 急変する北極気候システム及びその全球的な影響の総合的解明―GRENE北極気候変動研究事業研究成果報告2015―11月19日（木）　国立極地研究所１階交流アトリウ

Oxidation of CuSn alloy nanotree and application for gas sensors

The CuSn alloy nanotree formed by DC electroplating is a true three-dimensional (3D) structure with many branches that separate the trunk perpendicularly. We carried out the oxidation of CuSn nanotrees in atmosphere in order to study the possibility of such nanotrees for application to sensors. It was confirmed that the oxygen concentration in the CuSn nanotree oxide increased with temperature and reached 40 at. % at 350 °C. The optical reflectance spectra of the CuSn nanotree oxide formed at 250 °C showed a 3–4% reflectance in the wavelength range between 400 and 900 nm, and its behavior differed from those of Cu and Sn oxides formed at 250 °C. The temperature dependence of electrical resistivity for the CuSn nanotree oxide showed a typical semiconductor behavior. By the introduction of H2, O2, N2, and CO gases into the chamber, the resistance of the CuSn nanotree oxide responded against H2 most sensitively, as well as against O2 and CO gases. From the resistance change tendency, it is strongly suggested that the CuSn nanotree oxide is a p-type semiconductor, because it shows an increase in conductivity caused by the adsorption of a negative charge such as O−. However, the conductivity decreases with the adsorption of a positive charge such as H+. The present study suggests the high potential of the CuSn nanotree oxide as a gas sensor, since it has a very high surface-to-volume ratio

Methane Oxidation Potential of Arctic Wetland Soil of a Taiga-Tundra Ecotone in Northeastern Siberia

第6回極域科学シンポジウム分野横断セッション：[IA] 急変する北極気候システム及びその全球的な影響の総合的解明―GRENE北極気候変動研究事業研究成果報告2015―11月19日（木）　国立極地研究所１階交流アトリウ

Fast Domain Growth through Density-Dependent Diffusion in a Driven Lattice Gas

We study electromigration in a driven diffusive lattice gas (DDLG) whose continuous Monte Carlo dynamics generate higher particle mobility in areas with lower particle density. At low vacancy concentrations and low temperatures, vacancy domains tend to be faceted: the external driving force causes large domains to move much more quickly than small ones, producing exponential domain growth. At higher vacancy concentrations and temperatures, even small domains have rough boundaries: velocity differences between domains are smaller, and modest simulation times produce an average domain length scale which roughly follows $L \sim t^{\zeta}$, where $\zeta$ varies from near .55 at 50% filling to near .75 at 70% filling. This growth is faster than the $t^{1/3}$ behavior of a standard conserved order parameter Ising model. Some runs may be approaching a scaling regime. At low fields and early times, fast growth is delayed until the characteristic domain size reaches a crossover length which follows $L_{cross} \propto E^{-\beta}$. Rough numerical estimates give $\beta= >.37$ and simple theoretical arguments give $\beta= 1/3$. Our conclusion that small driving forces can significantly enhance coarsening may be relevant to the YB$_2$Cu$_3$O$_{7- \delta}$ electromigration experiments of Moeckly {\it et al.}(Appl. Phys. Let., {\bf 64}, 1427 (1994)).Comment: 18 pages, RevTex3.

Nano-honeycomb electrode based QCM sensor and its application for PPI detection

An anodic aluminon oxide (AAO)-based nano honeycomb electrode was coated on a quartz crystal for use as a sensing device in a quartz crystal microbalance (QCM) to monitor the protein-protein interactions (PPIs). As examples, we detected PPIs of anti-Bcl-2 and Bcl-2, and Bcl-2 and Bax in real time. A sensor with a flat Au electrode showed a tiny frequency shift upon sample injection. However, our fabricated device could detect 10 μg/mL of Bcl-2 and Bax in sequence.2016年度関西大学研究拠点形成支援経

Aspect ratio dependence of hysteresis property of high density Co wire array buried in porous alumina template

Abstract Co wire array with 50 nm intervals was formed by electrodeposition in porous alumina template that was formed on Si substrate. Coercive field of Co wire array under perpendicular magnetic field significantly increased when aspect ratio increased from 1.5 to 2.5. This behavior was well explained by the micromagnetic simulation when magnetic anisotropy axis was assumed to be parallel to the substrate.

Fabrication of nanocone arrays by two step metal assisted chemical etching method

This work develops a novel method for preparing a moth eye structure, which has a sub-wavelength periodical Si nanocone structure on Si (100) substrate, using two-step metal assisted chemical etching (MACE). The 1st and 2nd MACE were respectively performed with the intention to form perpendicular Si nanowire arrays on a Si substrate and sharpening the Si nanowire arrays. We found the inhomogeneous absorption and aggregation of Au particles used as a catalyst for 2nd MACE was important to obtain the nanocone shape. The obtained Si nanocone arrays showed superior anti-reflecting properties especially in wavelength below 600 nm compared to the Si nanowire arrays. A possible mechanism involved in the formation of the nanocone structure by the 2-step MACE is discussed in this paper.This work was supported by KAKENHI Grant Numbers 25790024, 25600048 and15K04602 from the Japan Society for the Promotion of Science (JSPS), Strategic Project to Support the Formation of Research Bases at Private Universities: Matching Fund Subsidy from the Ministry of Education, Culture, Sports, Science and Technology(MEXT), and Kansai University Subsidy for supporting Young Scholars 2013