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971.
Kazuhiro Ikeda Norimichi Kojima Yasuhiro Kobayashi Makoto Seto 《Hyperfine Interactions》2005,166(1-4):403-407
Cs2[AuI X 2][AuIII X 4](X = Cl, Br, and I) is well known for the three-dimensional perovskite-type gold mixed valence system. Recently, layered perovskite-type gold mixed valence complexes, [NH3(CH2) n NH3]2[(AuII2)(AuIIII4)(I3)2] (n = 7 and 8), have been synthesized. We have investigated the relationship between the structural dimensionality and the AuI–AuIII charge transfer interaction for Cs2[AuII2][AuIIII4] and [NH3(CH2) n NH3]2[(AuII2)(AuIIII4)(I3)2] (n = 7 and 8) by means of 197Au Mössbauer spectroscopy. 相似文献
972.
Toshinari Isono Takayuki Ikeda Ryuji Aoki Kenji Yamazaki Toshio Ogino 《Surface science》2010,604(21-22):2055-2063
Atomic force microscopy (AFM) was used to characterize morphology and chemistry on step-controlled single crystalline sapphire (0001) surfaces. Hydrophilicity on the surface can be evaluated using frictional force imaging. A sapphire surface that is covered with bunched steps accompanied with crossing steps clearly exhibits the phase-separation into two domains with different hydrophilicity, where an almost hydrophobic domain forms inside a hydrophilic area. By analyzing the histogram of the step height, we concluded that the difference in the hydrophilicity is associated with the surface reconstruction. We found that the phase-separation characterized by the hydrophilicity and charge potential self-organizes on the sapphire surface with specific step arrangements. We demonstrated selective adsorption of biomolecules on step-controlled surfaces as an example of the application. 相似文献
973.
The aim of this paper is to investigate the Dirichlet problem of prescribed mean curvature equations. We show the existence of a weak solution. The boundary of domains does not always satisfy the H-convexity condition. Our method is not to construct the barrier functions directly, but to use some uniform estimate for solutions of the approximating regularized solutions. 相似文献
974.
975.
976.
977.
It is known that color constancy does not hold in a photograph. This could be because the photograph is recognized as a two-dimensional paper. Based on the concept of the recognized visual space of illumination (RVSI), it is predicted that color constancy holds in the photograph if it is perceived as a 3-D scene. We examined whether the color constancy held under a special viewing condition. A photograph of a room under incandescent illumination was shown under daylight illumination. We tested the neutral color perception of a stimulus on the photograph both with and without a dimension-up viewing box showing the photograph alone monocularly. The results showed good color constancy when a subject observed the photograph with the viewing box. It was also shown that the degree of color constancy decreased for a jumbled photograph without 3-D information. Our results suggest that the recognition of a space and illumination are important in color perception. 相似文献
978.
979.
K. Akamatsu K. Nakahashi S. Ikeda H. Nawafune 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,24(1-3):377-380
Formation and structure of composite layer consisting of
polyimide films containing Ni nanoparticles were investigated.
The preparation method relies on KOH treatment on polyimide film
to form carboxyl acid groups and adsorption of Ni ions by ion
exchange followed by hydrogen reduction. The amount of Ni ions
adsorbed in polyimide films were found to be systematically
controlled by changing initial KOH concentration, subsequent ion
exchange time, pH and temperature. Cross-sectional TEM
observation revealed that Ni nanoparticles with 3-5 nm in
diameter were homogeneously dispersed in the surface modified
polyimide layer after heat treatment above 250
°C in H2
atmosphere. The size and distribution of the Ni nanoparticles
were strongly dependent on the heat treatment temperature,
indicating that this method allows microstructural tuning of
metal/polymer nanocomposites. 相似文献
980.
Takahiko Nojima Kenichi Yamashita Atsuko Takagi Makoto Takagi Yasuyuki Ikeda Hiroki Kondo Shigeori Takenaka 《Analytical sciences》2003,19(1):79-83
A ferrocenylnaphthalene diimide-based electrochemical hybridization assay (FND-EHA) was applied to the direct detection of a C-to-G transition in a codon (TCA) for Ser-447 of the human lipoprotein lipase (LPL) gene, which resulted in the termination of the LPL protein there. Either one of two 13-meric oligonucleotide probes, S447 WT and S447X MT, representing sequences complementary to those of the wild type (WT) and mutated (MT) forms, was immobilized on a gold electrode, followed by hybridization with chromosomal DNA extracted from human leukocytes under the condition in which both WT- and MT-type sequences can form a duplex. These two electrodes were soaked in an electrolyte containing FND under a condition [0.1 M HOAc/KOAc (pH 5.6) containing 0.1 KCl and 0.05 mM FND at 40 degrees C], in which only the MT duplex could undergo dissociation. FND was concentrated in proportion to the amount of the duplex formed on the electrode to give rise to a current signal. The electrochemical signal ratios obtained for WT/WT, WT/MT and MT/MT were close to the theoretical 2:1:0 with the S447 WT-modified electrode, and was again close to 0:1:2 with the S447X MT-modified one. 相似文献