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Based on the dispersionless KP (dKP) theory, we study a topological Landau-Ginzburg (LG) theory characterized by a rational
potential. Writing the dKP hierarchy in a general form treating all the primaries in an equal basis, we find that the hierarchy
naturally includes the dispersionless (continuous) limit of Toda hierarchy and its generalizations having a finite number
of primaries. Several flat solutions of the topological LG theory are obtained in this formulation, and are identified with
those discussed by Dubrovin. We explicitly construct gravitational descendants for all the primary fields. Giving a residue
formulae for the 3-point functions of the fields, we show that these 3-point functions satisfy the topological recursion relation.
The string equation is obtained as the generalized hodograph solutions of the dKP hierarchy, which show that all the gravitational
effects to the constitutive equations (2-point functions) can be renormalized into the coupling constants in the small phase
space.
Supported in part by NSF grant DMS-9403597. 相似文献
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Photolysis of acyclic monothioimides gave β-lactams and thioamides via Type II reaction involving γ-hydrogen abstraction by thiocarbonyl group. 相似文献
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Takashi Takeo Tomohiko Kanie Katsuhiro Satoh Shigeyuki Aoyama Haruhiko Itoh Hajime Hattori 《Optical Review》1995,2(5):366-370
In lightwave community antena television (CATV) systems as well as other optical fiber communication networks, a transmitted optical signal is known to be degraded by an intensity noise produced within the fiber due to the interference between the signal and doubly reflected light. We report on the improvements to the signal degradation due to the double Rayleigh backscattering by inserting optical isolators in the trunk lines of the systems. A carrier-to-noise ratio (CNR) has been calculated as a function of the number and the insertion loss of the isolators. The calculated results indicate that there is an optimum number of isolators, and if the insertion loss is less than 0.3 dB, the CNR degradation can be restored by more than 60%. To test the calculated results, we conducted experiments for the specific case of employing one isolator, and obtained good agreements between the two. 相似文献
69.
A new bisphosphine ligand, C8-BINAP, and C8-BINAP-stabilized palladium nanoparticles have been prepared; C8-BINAP was found to be an effective protecting ligand for preparing and stabilizing palladium nanoparticles with very small core size and narrow size distribution and the C8-BINAP-Pd nanoparticles behave as an efficient catalyst for carbon-carbon coupling reactions at room temperature. 相似文献
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