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101.
H. Kuroda I. Ikemoto K. Asakura H. Ishii H. Shirakawa T. Kobayashi H. Oyanagi T. Matsushita 《Solid State Communications》1983,46(3):235-238
FeK absorption spectra of FeCl3-doped polyacetylene [CH(FeCl3)y]x having y values of 0.024, 0.087 and 0.13, were measured by use of synchrotron radiation. The analyses of observed EXAFS data showed that Fe atom is surrounded by about four Cl atoms with Fe-Cl distance of 2.18–2.20 Å. It is concluded that the dopant exists mainly in the form of FeCl4-, and the following reaction takes place in the FeCl3 doping process. 2FeCl3 + e- → FeCl4- + FeCl2 相似文献
102.
The inelastic leptoproduction of heavy resonances J (J = J/ψ, Ψ,…) is investigated in a model where γvg → Jg is assumed to be the dominant mechanism. Analytic expressions for the differential cross section as well as for the helicity amplitudes are presented. A detailed numerical analysis of the angular distribution of the muon pair arising from the decay of the heavy resonance in its rest frame is presented. 相似文献
103.
104.
Hirosawa K Furumochi H Tada A Kannari F Takeoka M Sasaki M 《Physical review letters》2005,94(20):203601
To the best of our knowledge, we demonstrate for the first time the generation of photon number squeezing by spectral filtering for ultrabroadband light generated by microstructure fibers at 800 nm. A maximum squeezing of 4.6 dB is observed, corresponding to 10.3 dB after correcting for detection losses. We numerically analyzed the quantum dynamics of ultrashort laser pulse propagation through optical fibers by solving a nonlinear quantum Schr?dinger equation that included Raman scattering, especially for the quantum correlation of photon number fluctuation among frequency modes in broadband pulses. 相似文献
105.
We demonstrate the generation of up to the 63rd harmonic (lambda = 12.6 nm) of a Ti:sapphire laser pulse (150 fs, 10 mJ), using a prepulse- (210-ps,24-mJ) produced boron plasma as the nonlinear medium. The influence of various parameters on the harmonic conversion efficiency was analyzed. The steep decrease in intensity for low-order harmonics (up to 19th order) was followed by a plateau. Typical conversion efficiencies were evaluated to be 10(-4) (for a 3rd harmonic) to 10(-7) (within the plateau region). Harmonic generation appeared to be efficient for the plasma that comprised neutral atoms and singly ionized boron. 相似文献
106.
Sasaki K Sugou K Miyamoto K Hirai J Tsubouchi S Miyasaka H Itaya A Kuroda Y 《Organic & biomolecular chemistry》2004,2(19):2852-2860
The nonameric porphyrin assemblies constructed with the series of free base tetraphenylporphyrins Pn having four pyrazine moieties linked with alkyl chains of different lengths, (CH2)n (n = 1, 5, 9, 17, 30), and dimeric [meso-tetrakis(2-carboxy-4-nonylphenyl)porphyrinato]zinc(II), ZnP2, show the effective light-collection effect and the typical Forster-type energy transfer from ZnP2 to Pn. 相似文献
107.
R. A. Ganeev M. Morita A. I. Ryasnyanskii M. Baba D. Rau H. Fujii M. Suzuki M. Turu H. Kuroda 《Optics and Spectroscopy》2004,97(4):580-587
The nonlinear refractive indices γ and nonlinear absorption coefficients of ZrO2 films doped with CdS or ZnS nanoparticles, as well as with various metals, are measured. The effects of semiconductor and metal nanoparticles and annealing on the nonlinear optical properties of films are studied. The structural parameters of films, determined by electron microscopy and x-ray dispersion spectroscopy, are compared to the optical and nonlinear optical characteristics of these media. The high magnitude of γ of the films ((3±0.6)×10?11 cm2 W? 1) is attributed to the surface enhancement effect in semiconductor nanoparticles. On the basis of Z-scan data obtained at different intensities of radiation, it is shown that the variations in γ of the ZrO2:CdS(Cr) and ZrO2:ZnS(Mn) films are related to the generation of free carriers. 相似文献
108.
R. A. Ganeev M. Baba M. Morita A. I. Ryasnyanskii M. Suzuki M. Turu H. Kuroda 《Optics and Spectroscopy》2004,97(5):735-745
The saturated nonlinear absorption and Kerr nonlinearities of an aqueous pseudoisocyanine solution are investigated at the wavelengths of 532 and 529 nm with the use of pulsed laser radiation of different duration (8 ns and 475 fs). The measured values of the nonlinear refractive indices amount to ?6×10?12 (t=8 ns) and ?8×10?14 cm2W?1 (t=475 fs). The change in self-action effects in pseudoisocyanine from self-defocusing to self-focusing revealed in the case of increasing intensity of femtosecond laser pulses is attributed to the effect of a fifth-order nonlinear optical process. The nonlinear refractive index responsible for this process amounts to 4×10?24 cm4 W?2. The imaginary part of the third-order nonlinear susceptibility, responsible for the induced transparency of the pseudoisocyanine solution, is Imχ (3)=?2×10?12 esu. Temporal changes in the shape of nanosecond laser pulses due to the nonlinear refraction induced by a thermal process are analyzed. 相似文献
109.
Nakano H Takahashi K Okuyama Y Senoo C Tsugawa N Suzuki Y Fujita R Sasaki K Kabuto C 《The Journal of organic chemistry》2004,69(21):7092-7100
Cationic palladium (Pd)- and platinum (Pt)-phosphinooxazolidine catalysts 13a-c, 15a-d, 17a-c, and 19a-c were prepared from phosphinooxazolidine ligands 1-3, MCl(2) (M = Pd and Pt), and counterions, and the activities of the catalysts in the asymmetric Diels-Alder (DA) reactions of cyclic or acyclic dienes with imide dienophiles were investigated. These catalysts demonstrated high levels of catalytic activity. The cationic Pd-POZ complex 13c provided particularly excellent enantioselectivity (98% ee) in the DA reactions of cyclopentadiene with acryloyl-, crotonyl-, and fumaroyl-1,3-oxazolidin-2-ones (20a-c). 相似文献
110.
A new ketone synthesis by palladium-catalyzed cross-coupling reactions of esters with organoboron compounds 总被引:1,自引:0,他引:1
[reaction: see text] The palladium-catalyzed coupling reaction of 2-pyridyl esters with organoboron compounds is described. The reaction is compatible with various functional groups and proceeds under mild reaction conditions. The coordination of the nitrogen atom to Pd is a key step for efficient reaction. 相似文献