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71.
We observed the near field for a refractive index grating fabricated on a planar light waveguide circuit (PLC) by scanning an optically-trapped 100 nm diameter gold particle. We demonstrate that stable trapping and scanning occur with a Gaussian laser beam at the scan velocity of 1.6 m/s and Nd:YAG laser power of 25mW. The scattered Ar laser light from the gold particle is strong at high refractive indexes of the grating with periods of 1.06 m and 0.53 m both by s and p polarized illumination. In addition, we observed the surface profile of the optical disk tracking groove with and without the gold particle. © 2004 The Optical Society of Japan 相似文献
72.
Hitoshi?Yamada Kimihiro?Nishio Masahiro?Ohtani Hiroo?YonezuEmail author Yuzo?Furukawa 《Optical Review》2004,11(5):320-327
Inspired by a mechanism of biological vision systems, a model and a network of analog metal oxide semiconductor (MOS) circuits are proposed which display an optical flow with local adaptation to the relative velocity of a background image. A function of displaying an optical flow successfully worked as a result of simulations using the simulation program with integrated circuit emphasis (SPICE). A function of varying an optical flow at a certain instant by local adaptation was also demonstrated. The proposed network is suitable for the realization of a large-scale integrated circuit (LSI), which displays an optical flow with local adaptation to the local velocity of a background. 相似文献
73.
Fujimori A Nakahara H Ito E Hara M Kanai K Ouchi Y Seki K 《Journal of colloid and interface science》2004,278(1):184-191
With comb polymers with different kinds of fluorocarbon side-chains, significant effects of spreading solvents on the monolayers at the air/water interface and the molecular arrangement in the deposited films could be found by the use of trifluoroacetic acid and its mixed solvents with n-hexane, depending on the atoms, fluorine or hydrogen, substituted at the end of the fluorocarbon side-chains. These facts are probably due to intralayer hydrogen bonding cooperating with the carbonyl groups of the long-chain esters. The deposited films of solid substrates were characterized by polarized near-edge X-ray absorption fine structure (NEXAFS) spectroscopy as well as in-plane X-ray diffraction and scanning electron and atomic force microscopy. 相似文献
74.
Wavelength tuning characteristics of a fabry-perot semiconductor laser with an external short cavity
Wavelength tuning characteristics of a Fabry-Perot semiconductor laser with an external short cavity are analyzed, in which
the oscillation wavelength can be changed by slightly altering the external cavity length. Analysis is based on rate equations
for an optical power and carrier density. It is shown that the wavelength tuning range is dominated by a change of carrier
density through the effect of carrier-induced refractive index change in the active layer of a laser diode. This depends on
effective coupling coefficients of the optical field iteratively reflected back to the laser diode by the external mirror,
and on reflection coefficients of an anti-reflection coated laser facet and the external mirror which compose the external
cavity. The effective coupling coefficient is also derived using the waveguide theory and Kirchhoff ’s theory. Finally, an
unstable condition which may limit a stable wavelength tuning range is shown by results of a linear stability analysis of
rate equations. 相似文献
75.
Hiroo Hasebe Hironori Kuboki Hiroki Okuno Isao Yamane Hiroshi Imao Nobuhisa Fukunishi Masayuki Kase Osamu Kamigaito 《Journal of Radioanalytical and Nuclear Chemistry》2014,299(2):1013-1018
New carbon-nanotube–sputter-deposition-carbon (CNT–SDC) foils were developed and used in the U beam time at the RIKEN RI Beam Factory (RIBF) from October to December 2011. The lifetimes of these new foils were drastically extended, and stable, high-intensity U beams were successfully provided to users. The lifetime of the CNT–SDC foils was 2–5 C, which was 100 times longer than those of static C-foils previously used. The qualitative analysis of the CNT–SDC foils clearly showed that the CNT structure and bundles were broken by beam irradiation. In addition, it was found that CNT bundles in the CNT–SDC foil were grown after the carbon deposition procedure. This structure was considered to be the reason that the CNT–SDC foils maintain advantages of both CNT and SDC foils. 相似文献
76.
A convenient one‐pot method for the preparation of (4Z)‐4‐(arylmethylidene)‐5‐ethoxy‐1,3‐oxazolidine‐2‐thiones 2 and 3 from ethyl (2Z)‐3‐aryl‐2‐isothiocyanatoprop‐2‐enoates 1 , which can be easily prepared from ethyl 2‐azidoacetate and aromatic aldehydes, has been developed. Thus, these α‐isothiocyanato α,β‐unsaturated esters were treated with organolithium compounds, including lithium enolates of acetates, to provide 5‐substituted (4Z)‐4‐(arylmethylidene)‐5‐ethoxy‐1,3‐oxazolidine‐2‐thiones, 2 , and 2‐[(4Z)‐(4‐arylmethylidene)‐5‐ethoxy‐2‐thioxo‐1,3‐oxazolidin‐5‐yl]acetates, 3 . 相似文献
77.
Takao Nanba Yasuhito Urashima Mikihiko Ikezawa Makoto Watanabe Eiken Nakamura Kazutoshi Fukui Hiroo Inokuchi 《International Journal of Infrared and Millimeter Waves》1986,7(11):1769-1776
At the UVSOR Facility, Institute for Molecular Science, the practical use of the synchrotron radiation as a far-infrared light source has started. A spectroscopic system has been constructed at the beam line BL6A1 of UVSOR storage ring, which covers the wavenumber region from 5 to 250 cm–1. The cross sectional diameter of the light beam at the sample position is as small as 3 mm with the angular divergence of about 100 mrad. The system has been made mainly for the transmission and reflection measurements of small samples with small angular divergence by the use of the high brightness of the synchrotron radiation. Examples of observed transmission and reflectivity spectra are shown. 相似文献
78.
Consistency and monotonicity in assignment problems 总被引:1,自引:0,他引:1
Hiroo Sasaki 《International Journal of Game Theory》1995,24(4):373-397
This paper presents axiomatic characterizations of the core of assignment problems. In the main axiomatization theorem we use six axioms including the consistency (CONS) and the weak pairwise-monotonicity (W.P.MON) which are firstly proposed and defined for this setup in the present paper. Since an assignment problem may be converted into a model of a private ownership economy with indivisible goods and the core of the assignment problem coincides with the set of the competitive allocations of the economy, our characterization theorems also give axiomatic characterizations of the set of competitive allocations. Because the consistency is a desirable property of resource allocation mechanisms, our main result gives a new normative implication of competitive equilibria. 相似文献
79.
The tetracyclic compounds ~3 and ~4 corresponding to A-homograyanotoxane system were synthesised by a thermolysis of the benzocyclobutene ~8, followed by a Wagner-Meerwein rearrangement of the kaurane type of compounds ~15 and ~16. 相似文献
80.
A method was devised for detecting both the molecular mass and the isoelectric point (pI) of the lectin in the seed extract of Momordica charantia on a nitrocellulose membrane. It was associated with the electrophoretic blotting technique that produced replicas of proteins separated on micro two-dimensional polyacrylamide gels. The red blood cell adherence procedure on the blotted membrane exhibited only one red spot with molecular mass 107.10(3) and pI 5.3, which indicated the lectin activity. Additionally, the lectin appeared to be a glycoprotein with mannose and/or glucose, because it was stained by concanavalin A-peroxidase staining. 相似文献