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111.
112.
Photo-induced edge-shift affect in As2S3 film has been studies for different intensities of incident light. This process depends only on the total energy E of light. A simple experimental relationship between shift of edge Δλ and E has been obtained, which coincides with a theretical prediction deduced from a model based on a first-order reaction. 相似文献
113.
Nuclear magnetic relaxation times, T1 and T2 are measured in dilute Au-V alloys for 1–300 K. A value for T1T = 17.0 ± 0.5 msK is obtained. 相似文献
114.
Shigeyuki Mayama Toshikazu Tani Tamio Ueno Kazumasa Hirabayashi Tadakazu Nakashima Hiroshi Fukami Yukio Mizuno Hiroshi Irie 《Tetrahedron letters》1981,22(22):2103-2106
The major phytoalexin from oat leaves has been identified as 2-[2-(4-hydroxyphenyDethenyl] -6-hydroxy-4H-3,1-benzoxazin-4-one (). 相似文献
115.
A ring-closing metathesis reaction of allenynes occurred at room temperature in the presence of a molybdenum alkylidene complex to give ring-closed vinylallenes. The vinylallene skeletons were constructed by a metathesis-type reaction between the alkyne moiety and the proximal carbon-carbon double bond of the allene moiety. [reaction: see text] 相似文献
116.
A bent photonic crystal waveguide was fabricated by use of a lattice pattern of a circular photonic crystal that allowed high transmission for a broad band of wavelengths with a small radius of curvature at a bend. The waveguide was fabricated by use of alumina rods with a diameter of 3 mm. Windows of high transmission as a result of waveguiding were observed near 9 and 15 GHz. By measurement of the relative wave intensity [E]2 along the line defects, the propagation losses in the straight and the bent sections were estimated at 9.3 GHz to be 0.04 and 0.03 dB/mm, respectively. 相似文献
117.
Shibata T Fujimoto T Yokota K Takagi K 《Journal of the American Chemical Society》2004,126(27):8382-8383
An asymmetric [2+2+2] cycloaddition of an alpha,omega-diyne, possessing ortho-substituted aryl groups on its terminus, and a monoalkyne with oxygen functionalities gave various axially chiral teraryl compounds. The coupling proceeded with extremely high enantio- (>99.5% ee) and diastereoselectivities (dl/meso = >95/5) when catalyzed by an iridium-chiral phosphine complex. As the products were readily transformed into diol compounds by deprotection without racemization, the present procedure provides access to a new chiral pool of diol compounds with C2 symmetry. 相似文献
118.
Anisotropic optical properties of mechanically aligned single-walled carbon nanotubes in polymer 总被引:1,自引:0,他引:1
M.?IchidaEmail author S.?Mizuno H.?Kataura Y.?Achiba A.?Nakamura 《Applied Physics A: Materials Science & Processing》2004,78(8):1117-1120
We have prepared aligned single-walled carbon nanotubes in polymer by mechanical stretching. The polarized absorption and Raman spectra of the aligned samples have been investigated. The optical transitions in nanotubes strongly depend on the angle between the polarization of the incident light and the nanotube axis: the absorbance measured at the peak energy shows a maximum at =0°, and they are suppressed at =90°. Raman spectra also show strong polarization dependence, which is mainly determined by the dependence of the oscillator strength of optical transitions in nanotubes. PACS 71.35.Cc; 78.30.-j; 78.67.Ch; 73.22.-f 相似文献
119.
The amount of information transmissible through a communications channel is determined by the noise characteristics of the channel and by the quantities of available transmission resources. In classical information theory, the amount of transmissible information can be increased twice at most when the transmission resource is doubled for fixed noise characteristics. In quantum information theory, however, the amount of information transmitted can increase even more than twice. We present a proof-of-principle demonstration of this superadditivity of classical capacity of a quantum channel by using the ternary symmetric states of a single photon, and by event selection from a weak coherent light source. We also show how the superadditive coding gain, even in a small code length, can boost the communication performance of the conventional coding technique. 相似文献
120.
A cyclic dimer of chiral saddle-shaped porphyrin with p-xylylene linkers, upon interaction with mandelic acid, showed an enhanced circular dichroism activity, which was more than 7 times as large as that of a monomeric reference. 相似文献