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41.
Hideaki Furukawa Tsuyoshi Konishi Yoshinori Oshita Wanji Yu Kazuyoshi Itoh Yoshiki Ichioka 《光学学报》2003,23(Z1)
We demonstrate a suppression effect of a crosstalk among a target and similar header signals using the header recognition filter designed by a design technique of the multiple-object discriminant filter. 相似文献
42.
43.
A binary subwavelength structure for multilevel phase modulation can be designed by our previously proposed deterministic
design method without iterative optimization method. To use our design technique in various applications of a computer generated
hologram (CGH) like an array illuminator, beam-shaping, signal processing, and so on, an image quality of a reconstructed
image from a CGH has become much more important. In this paper, we verify the image quality of a reconstructed image from
a CGH designed by our method in terms of the modulation transfer function (MTF) and the spatial resolution. Simulation results
show that our technique can theoretically achieve a MTF of more than 99% over a wide range and a spatial resolution of less
than 9.66μm. 相似文献
44.
Using elastic recoil detection analysis and low energy electron diffraction we have investigated the adsorption process of hydrogen on the
surface. We find that (1) room temperature adsorption of atomic hydrogen induces a structure transformation from the
to Si(111)-1 × 1-Ag(H) structures, (2) a saturation coverage of hydrogen is 1.5 monolayer, which almost coincides with the one on a clean 7 × 7 surface, and (3) thermal desorption of hydrogen from the ordered 1 × 1-Ag(H) surface results in the recovery of the original
surface. 相似文献
45.
46.
The nickel Kalpha spectra of oxides, halides (NiF2, K2NiF6, NiCl2, NiBr2), complex compounds, and metal are measured with two different double-crystal X-ray fluorescence spectrometers. The peak shifts and line width changes due to the changes in the chemical states are reported. High reproducibility has been shown for the chemical shift and line width measurements. The DV-Xalpha molecular orbital calculation at the ground and the 1s(-1) hole states was performed to prove that the chemical effect originats from the charge-transfer mechanism. 相似文献
47.
Manabu Kiguchi Tatsuya Konishi Shinichi Miura Kei Murakoshi 《Physica E: Low-dimensional Systems and Nanostructures》2005,29(3-4):530
We have mechanically fabricated Ni and Cu nano-constrictions in solution to study their quantized conductance behavior under electrochemical potential control. Conductance quantization was observed at both metals in solution at room temperature for the first time. The conductance of Cu nano-constriction was quantized in units of G0(=2e2/h). A sharp 1G0 peak was observed in the conductance histogram. For Ni, a rather broad peak at 1–1.5G0 was observed in the histogram. The conductance quantization behavior was discussed by comparing previously documented results of nano-constrictions fabricated in air or ultra-high vacuum conditions, with those fabricated in solution. 相似文献
48.
Dr. Shintaro Ishida Dr. Takashi Abe Dr. Fumiya Hirakawa Tomoyuki Kosai Katsuhiro Sato Prof. Dr. Mitsuo Kira Prof. Dr. Takeaki Iwamoto 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(43):15100-15103
A persistent dialkylsilanone was synthesized by the dehydrobromination of a dialkylbromosilanol with tris(trimethylsilyl)silyl potassium in solution at ?80 °C: It was characterized by NMR and IR spectroscopy, and was tested in several reactions. In 29Si NMR spectrum in [D8]toluene, the signal due to the unsaturated silicon nuclei was observed at 128.7 ppm. Reactions of the dialkylsilanone with water and mesitonitrile oxide gave a silanediol and a [2+3] cycloadduct, respectively. The silanone remains intact in [D8]toluene below ?80 °C for at least two days, while it undergoes unprecedented isomerization to give a siloxysilene by means of 1,3‐silyl migration at higher temperatures. 相似文献
49.
An efficient one-pot procedure for the preparation of 4-substituted 4-alkoxy-1,4-dihydro-3,1-benzoxazine-2-thiones from 2-isothiocyanatobenzoates has been developed. Thus, 2-isothiocyanatobenzoates were reacted with organolithiums including lithium enolates of acetates and tertiary acetamides in THF at −78 °C to give the desired products in generally good yields. 相似文献
50.
Monitoring the aggregation processes of amyloid-β using a spin-labeled, fluorescent nitroxyl radical
Mito F Yamasaki T Ito Y Yamato M Mino H Sadasue H Shirahama C Sakai K Utsumi H Yamada K 《Chemical communications (Cambridge, England)》2011,47(17):5070-5072
Amyloid nitroxyl radical (nitroxide) ligands were used to detect amyloid-β fibrils, the main constituents of senile plaques in Alzheimer's disease, using anisotropic ESR spectra, and were found to affect the aggregation process due to the radical functionality. These compounds have great potential as novel and multifunctional probes, combining spin labels, spin probes, and fluorescence probes. 相似文献