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71.
Experimental characterization of quantum-correlated twin beams and a quantum channel with twin beams
We report the generation and characterization of quantum-correlated twin beams and their application to a quantum channel. Compared with our previous results, the characterization of twin beams and the quantum channel have been studied with 7.0-dB intensity difference squeezing. The measured inference variance of twin beams is decreased to 0.40 ± 0.02. For the quantum channel, the bit error rate will be 0.035 by using 7.0-dB intensity difference squeezing compared with our previous result of 0.067 by using 4.9-dB intensity difference squeezing. 相似文献
72.
D. Watanabe H. Ohoyama T. Matsumura T. Kasai 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2006,38(1):219-223
The MJ-state selection of the metastable rare-gas (Rg*) was achieved by
a magnetic hexapole that is composed of permanent magnets. The performance of the magnetic hexapole was examined by characterizing
the velocity distribution and the spatial profile of the state selected Rg* beam. The characterization was carried out using
position resolved time-of-flight
analysis and its trajectory simulation. The magnetic hexapole enhanced the beam intensity at least one order of magnitude
owing to the focusing effect. In addition, the magnetic hexapole was found to act as a good velocity selector. 相似文献
73.
Hiroshi Ito Brian C. Trinque Paul Kasai C. Grant Willson 《Journal of polymer science. Part A, Polymer chemistry》2008,46(5):1559-1565
Electron‐deficient 2‐trifluoromethylacrylates (TFMA) undergo radical copolymerization with electron‐rich norbornene derivatives, vinyl ethers, and styrene derivatives, which can be described by the penultimate model much better than by the commonly employed terminal model. In an attempt to directly observe the effect of the CF3 group in the penultimate unit on the radical reactivity, we employed the Giese's mercury method. 4,4,4‐Trifluorobutyl and n‐butyl radicals produced from respective alkylmercuric chlorides were competitively reacted with t‐butyl 2‐trifluoromethylacrylate (TBTFMA) and t‐butyl methacrylate (TBMA) and the products analyzed with gas chromatography. While TBTFMA has been found to be about 24times more reactive than TBMA toward the n‐butyl radical, the former is about 12 times more reactive than the latter toward the 4,4,4‐trifluorobutyl radical. Thus, the reactivity of the propagating radical toward TBTFMA in comparison with TBMA is suppressed by a factor of two when the penultimate unit has the CF3 group. We observed a sextet electron spin resonance of the TFMA propagating radical with a coupling constant of ca. 25 gauss between the β‐proton and β‐fluorine. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1559–1565, 2008 相似文献
74.
The threshold logic filter is an important nonlinear filter class, which is defined by a threshold logic function of binary input values. It is proved in this paper that not all positive self-dual logical functions are threshold functions if the number of input variables is 5 or more. The positive self-dual logical filter is a limited class but includes almost all filters for noise removal. Our result means that not all positive self-dual filters can be expressed by one operation of the threshold logic filters. In the sense of the filter expression by neural networks, the two-layer network cannot always optimize even this limited class. 相似文献
75.
We consider hydrogenase-based nanomaterials for possible use as anode electrode catalysts in polymer electrolyte fuel cells (PEFCs). We choose Fe-only hydrogenase component of Desulfovibrio desulfuricans (DdHase) as a hydrogenase complex, and investigate its catalytic activity for H2 dissociation using ab initio calculations based on density functional theory (DFT). We found two possible H-H bond cleavage pathways, which are heterolytic and possess low activation barriers. Moreover, the H2 dissociation can be promoted by inducing spin polarization of the H2 adduct. We report that hydrogenase or hydrogenase-based nanomaterials can manipulate to exhibit the catalytic activity equivalent to the well-known platinum catalyst. 相似文献
76.
Kasai R Hara K Dokan R Suzuki N Mizutare T Yoshihara S Yamasaki K 《Chemical & pharmaceutical bulletin》2000,48(8):1226-1227
Incubation of ginseng sapogenins with microsomes from rat liver resulted in formation of their 20,24-epoxides as major metabolites. Identification of the metabolites was performed by HPLC, FAB-MS and EI-MS. 相似文献
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80.
From the pericarps of Sapindus emarginatus (Sapindaceae), three new acetylated triterpene saponins were isolated together with hederagenin and five known triterpene saponins, as well as one known sweet acyclic sesquiterpene glycoside, mukurozioside IIb. The structures of new compounds were elucidated as hederagenin 3-O-(2-O-acetyl-beta-D-xylopyranosyl)-(1-->3)-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranoside, 23-O-acetyl-hederagenin 3-O-(4-O-acetyl-beta-D-xylopyranosyl)-(1-->3)-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranoside and oleanolic acid 3-O-(4-O-acetyl-beta-D-xylopyranosyl)-(1-->3)-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranoside by chemical and spectroscopic data. 相似文献