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61.
Gold nanowires were synthesized at 150 K by electron beam thinning of a gold thin foil in an UHV electron microscope. The gold nanowires were found to have a helical multishell structure (HMS). One particular nanowire, which was thinner than the 7-1 HMS nanowire, was found to have a tubular structure. The gold single wall nanotube is composed of five atomic rows that coil about the tube axis. The diameter was 0.4 nm and the pitch was 11 nm. The stability of the (5,3) nanotube was discussed in terms of the shear deformation of the triangular network of gold atoms. 相似文献
62.
63.
Yoshifumi Hanada Teizi Tanizaki Minoru Koga Hiroaki Shiraishi Mitsuyuki Soma 《Analytical sciences》2002,18(4):445-448
Liquid chromatography/mass spectrometry (LC/MS) has been applied to the analysis of triphenylboron, which has been produced as a substitute for organotin compounds, in water. Although commercial triphenylboron compounds are produced as pyridinyl complexes, the chemical form in water is supposed to be mainly triphenylboron after liberating pyridine. The triphenylborons were extracted from water with an Empore C18 extraction disk under acidic condition, and the extracts were introduced directly into a liquid chromatograph-mass spectrometer equipped with a negative ion electrospray ionization interface. Identification of the compounds was performed with specific ions produced from the triphenylboron, and a quantitative analysis was carried out using the peak areas. The average recoveries from distilled water, seawater and river water at 0.30 ng/ml were 92.3, 100 and 85.3%, respectively. A detection limit of 0.023 ng/ml for triphenylboron was achieved. 相似文献
64.
Norikazu Nakayama Satoru Kijima Satoshi Itoh Toyoharu Ohata Akira Ishibashi Yoshifumi Mori 《Optical Review》1995,2(3):167-170
Green light-emitting diodes (LEDs) were fabricated employing a ZnCdSe/ZnSSe triple quantum-well (TQW) active region surrounded by ZnMgSSe cladding layers grown on an n-type (100) GaAs substrate by molecular beam epitaxy (MBE). A 3.5 mW pure green emission was observed for the surface-emitting LED device at a peak wavelength of 513.3 nm (2.415 eV) with a spectral half-width of 11.7 nm (55 meV) under a 20 mA (4.6 V) direct current at room temperature (25°C). These correspond to an external quantum efficiency of 7.2%, a power conversion efficiency of 3.8%, a luminous current efficiency of 66 lm/A, and a luminous efficiency of 14 lm/W. 相似文献
65.
66.
Toshikazu Shimada Yoshifumi Katayama Kiyokazu Nakagawa Hirokazu Matsubara Masatoshi Migitaka Eiichi Maruyama 《Journal of Non》1983
The structural properties of microcrystalline silicon (μc-Si) are studied by Raman scattering. It is found that the intensity of each Raman band closely correlates with the absorption coefficient in the interband region and that the Raman band at ca. 150 cm?1 is a sensitive probe to randomness of Si-Si bonding structure in μc-Si. 相似文献
67.
68.
Yoshifumi Muroi 《Applied Mathematical Finance》2013,20(2):155-190
In the last decade, many kinds of exotic options have been traded and introduced in the financial market. This paper describes a new kind of exotic option, lookback options with knock‐out boundaries. These options are knock‐out options whose pay‐offs depend on the extrema of a given securities price over a certain period of time. Closed form expressions for the price of seven kinds of lookback options with knock‐out boundaries are obtained in this article. The numerical studies have also been presented. 相似文献
69.
Yasuto Uchio Junzo Toyota Hiroshi Nozaki Mitsuru Nakayama Yoshifumi Nishizono Tsunao Hase 《Tetrahedron letters》1981,22(41):4089-4092
The structures of lobohedleolide (1) and (7Z)-lobohedleolide (2), two new cembranolides containing the α,β-unsaturated carboxylic acid system isolated from the Japanese soft coral Lobophytum hedleyi Whitelegge, were elucidated from spectral and chemical evidence, and the absolute configuration of (1) was determined by X-ray analysis of its p-bromophenacyl ester (9). Lobohedleolide (1) showed growth inhibition of the in vitro Hella cells. 相似文献
70.
This research originally was aimed at modeling all flows (except free-molecular) by systems of hyperbolic-relaxation equations
(moments of the Boltzmann equation), and developing efficient numerical methods for these. Such systems have many potential
numerical advantages, mainly because there are no second or higher derivatives to be approximated. This avoids accuracy problems
on adaptive unstructured grids, and the source terms, though often stiff, are only local; the compact stencils facilitate
code parallelization. A single code could simulate flows up to intermediate Knudsen numbers, and be hybridized with DSMC where
needed. In this project, one major problem arose that we have not yet solved: the accurate representation of shock structures.
This makes the methodology currently unsuited for, e.g., re-entry flows. We have validated it for subsonic and transonic flows
and are concentrating on applications to MEMS-related flows. We discuss the challenges of our approach, present numerical
algorithms and results based on the 10-moment model, and report progress in our latest research topic: formulating accurate
solid-boundary conditions. 相似文献