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81.
The generating function of the photon counting distribution is studied under consideration of the spatial coherence. The high order factorial moments are induced from the generating function, and are found to be experimental proof for the theory. The behavior of the second factorial moment is investigated for the purpose of spectroscopy of Rayleigh scattered light. The factorial moment measurements are made by using a digitalized electric system. The spectral line shape is determined quantitatively under various spatial coherence conditions. 相似文献
82.
The electrophoretic movements of polystyrene latex particles suspended in water and in electrolyte solutions have been investigated with an optical beating technique. When two kinds of particles in water move in the presence of an external electric field, it is observed that the laser light scattered by these particles exhibits a shifted spectrum with a single peak profile, even if the electrophoretic mobilities of the two kinds of particles are different to each other. However, when these particles are suspended in an electrolyte solution, two separate spectral lines are observed which correspond to the velocity of each kind of particles. 相似文献
83.
The frequency spectrum of tungsten field emission current instability when H2 and CO are adsorbed is measured. The power spectrum density slope W(f) versus f is found to be different for both cases. The slopes are about ?1 and ?1.5 for H2 and CO adsorption, respectively. The dependency of frequency spectra on the crystal planes is also measured. The amplitude of W(f) is found to be largest for (310) and lowest for (112). 相似文献
84.
Yoshiumi Kohno Eriko Haga Keiko Yoda Masashi Shibata Choji Fukuhara Yasumasa Tomita Yasuhisa Maeda Kenkichiro Kobayashi 《Journal of Physics and Chemistry of Solids》2014
Because of its non-toxicity, naturally occurring anthocyanin is potentially suitable as a colorant for foods and cosmetics. To the wider use of the anthocyanin, the immobilization on the inorganic host for an easy handling as well as the improvement of the stability is required. This study is focused on the adsorption of significant amount of the natural anthocyanin dye onto mesoporous silica, and on the stability enhancement of the anthocyanin by the complexation. The anthocyanin has successfully been adsorbed on the HMS type mesoporous silica containing small amount of aluminum. The amount of the adsorbed anthocyanin has been increased by modifying the pore wall with n-propyl group to make the silica surface hydrophobic. The light fastness of the adsorbed anthocyanin has been improved by making the composite with the HMS samples containing aluminum, although the degree of the improvement is not so large. It has been proposed that incorporation of the anthocyanin molecule deep inside the mesopore is required for the further enhancement of the stability. 相似文献
85.
Anoklase J.‐L. Ayitou Dr. Gaku Fukuhara Elango Kumarasamy Prof. Dr. Yoshihisa Inoue Prof. Dr. J. Sivaguru 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(13):4327-4334
Enantiospecific axial‐to‐point chiral transfer in light‐induced transformations was efficient under elevated pressure at high temperatures. Model photoreactions with atropisomeric compounds showed higher enantioselectivity in the photoproducts under elevated pressure. The ee values in the photoproducts were rationalized based on the increased stability of optically pure atropisomeric compounds at elevated pressure, even at high temperatures. 相似文献
86.
87.
Shinji Fukuhara 《Abhandlungen aus dem Mathematischen Seminar der Universit?t Hamburg》2014,84(2):139-153
We will obtain generating functions of even Dedekind symbols with polynomial reciprocity laws. The generating functions are expressed in terms of Kronecker’s double series. We also establish reciprocity laws satisfied by these generating functions. As an application, we demonstrate new Eisenstein series identities which involve the derivatives of the first and second order. 相似文献
88.
Synthesis of 7,8‐Dehydropurpurin Dimers and Their Conversion into Conformationally Constrained β‐to‐β Vinylene‐Bridged Porphyrin Dimers
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Norihito Fukui Prof. Dr. Hideki Yorimitsu Dr. Jong Min Lim Prof. Dr. Dongho Kim Prof. Dr. Atsuhiro Osuka 《Angewandte Chemie (International ed. in English)》2014,53(17):4395-4398
7,8‐Dehydropurpurin has attracted much attention owing to the dual 18π‐ and 20π‐electron circuits in its macrocyclic conjugation. The two‐fold Pd‐catalyzed [3+2] annulation of meso‐bromoporphyrin with 1,4‐diphenylbutadiyne furnished 7,8‐dehydropurpurin dimers. The 8a,8a‐linked dimer displays a red‐shifted and enhanced absorption band in the NIR region and a small electrochemical HOMO–LUMO band gap as a consequence of efficient conjugation between the two coplanar 7,8‐dehydropurpurin units. Treatment of this dimer with N‐bromosuccinimide in chloroform and ethanol gave β‐to‐β vinylene‐bridged porphyrin dimers. Owing to the highly constrained conformations, these dimers exhibit perturbed absorption spectra, small Stokes shifts, and high fluorescence quantum yields. 相似文献
89.
Asymmetric 1,4-addition of arylboronic acids to (E)-methyl 2-cyano-3-arylpropenoates proceeded in the presence of a rhodium catalyst (3 mol %) coordinated with a chiral diene ligand, (R,R)-Ph-bod*, to give high yields of the corresponding methyl 3,3-diaryl-2-cyanopropanoates with high enantioselectivity (up to 99% ee). This catalytic asymmetric transformation was applied to the asymmetric synthesis of (R)-tolterodine. 相似文献
90.
Saito N Akagawa K Ito M Takazawa A Hayano Y Saito Y Ito M Takami H Iye M Wada S 《Optics letters》2007,32(14):1965-1967
We report on a sodium D(2) resonance coherent light source achieved in single-pass sum-frequency generation in periodically poled MgO-doped stoichiometric lithium tantalate with actively mode-locked Nd:YAG lasers. Mode-locked pulses at 1064 and 1319 nm are synchronized with a time resolution of 37 ps with the phase adjustment of the radio frequencies fed to acousto-optic mode lockers. An output power of 4.6 W at 589.1586 nm is obtained, and beam quality near the diffraction limit is also achieved in a simple design. 相似文献