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Gu Chaohao 《Letters in Mathematical Physics》1992,26(3):199-209
A class of integrable systems of nonlinear partial differential equations in the spacetime R
n+1
is introduced. Single and multi-soliton solutions are constructed by using the Darboux matrix method. It is proved that as t±, a k multi-soluton solution splits asymptotically into k single solitons. Moreover, the interaction between solitons is elastic if we consider their magnitudes only.The work is C. H. Gu supported by the Chinese National Program for fundamental research nonlinear science. 相似文献
44.
Shao-Chen Yang Qihuang Gong Zongju Xia Y. H. Zou Y. Q. Wu D. Qiang Y. L. Sun Z. N. Gu 《Applied physics. B, Lasers and optics》1992,55(1):51-53
The nonlinear third-order optical susceptibility of C70 in a toluene solution is measured for the first time by the method of degenerate four-wave mixing using 10 ns laser pulses at 1.06 m. The third-order susceptibility X
in
(3)
is 5.6×10–12 esu for a C70 toluene solution at a concentration of 0.476 g/l. The correspondent magnitude of the hyperpolarizability 1111 of the C70 molecule is 1.2×10–30 esu which is in a good agreement with the prediction given by the model of a free electron in a spherical box. 相似文献
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J T Arnason B Guèrin M M Kraml B Mehta R W Redmond J C Scaiano 《Photochemistry and photobiology》1992,55(1):35-38
Sanguinarine, a commercial drug exhibiting antimicrobial and antitumor properties, was studied with respect to its basic photochemical characteristics and also with regard to its phototoxicity to mosquito larvae (Aedes atropalpus). Sanguinarine proved to be clearly phototoxic to larvae, with an LD50 of 0.096 mg/mL with near UV exposure as compared with 23.3 mg/mL without. Flash photolysis experiments enabled the study of the triplet state of sanguinarine to be undertaken. Quenching by oxygen occurs with a rate constant of 6 x 10(9) M-1s-1 and time-resolved emission studies indicate that sanguinarine produces a significant amount of singlet oxygen (phi delta = 0.16) as does the isoquinoline alkaloid, berberine (phi delta = 0.25). These values represent the first direct quantitative measurements of photosensitization parameters of these compounds. Additionally, sanguinarine exhibits efficient electron donation properties, undergoing reaction with methyl viologen with a rate constant greater than 10(10) M-1s-1, but is a poor electron acceptor. Phototoxicity of sanguinarine can thus be explained in terms of its photosensitization properties. 相似文献
49.
The enantioselective hydrogenation of endocyclic enones has been a historical problem for homogeneous catalysis.We herein report an efficient method to reduce e... 相似文献
50.
Lithium-sulfur(Li-S)batteries are promising candidates for high density electrochemical energy storage systems.However,the poor conductivity of S and the shuttl... 相似文献