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81.
82.
Jaume Casabó Andreu Solans Carmen Diaz Joan Ribas Alexandre Seguí Montserrat Corbella 《Transition Metal Chemistry》1985,10(4):128-130
Summary Mixed difluoro(diamine)(diamme)chromium(III) complexes have been synthesized with ethylenediamine (en), 1,3 propanediamine(tn) and 1,2-cyclohexanediamine(chxn):trans-[CrF2(aa)(bb)]Br (aa=en, bb=tn; aa=tn, bb= chxn) andcis-[CrF2(aa)(bb)]Br (aa=en, bb=chxn). The corresponding fluoroaqua(diamine) (diamine)chromium(III) complexes have been prepared by acid hydrolysis as perchlorate or iodide salts. All have been characterized by chemical analysis, electronic and i.r. spectra and conductivity measurements. 相似文献
83.
84.
The solvent effect on the fluoride exchange reaction has been studied by means of ab initio calculations using the 3-21G basis set. It is shown that the motion of the solvent molecules is an important part of the reaction coordinate. 相似文献
85.
Jaume Garriga 《International Journal of Theoretical Physics》2003,42(6):1343-1367
We discuss the effective action of moduli fields in warped brane-world compactifications. For definiteness, a two-brane model with a bulk dilaton field and a power-law warp factor is considered. After deriving the classical four-dimensional effective action for the moduli, we present the calculation of the one-loop effective potential induced by bulk fields. A detailed discussion of renormalization is given, with emphasis on the local worldsheet operators which are generated. Finally, we outline the possible role of these operators in the stabilization of the moduli. 相似文献
86.
Option pricing and perfect hedging on correlated stocks 总被引:2,自引:0,他引:2
We develop a theory for option pricing with perfect hedging in an inefficient market model where the underlying price variations are autocorrelated over a time τ0. This is accomplished by assuming that the underlying noise in the system is derived by an Ornstein-Uhlenbeck, rather than from a Wiener process. With a modified portfolio consisting in calls, secondary calls and bonds we achieve a riskless strategy which results in a closed and exact expression for the European call price which is always lower than Black-Scholes price. We obtain the same price and a modified delta hedging if we start from an effective one-dimensional market model. We compare these strategies and study the sensitivity of the call price to several parameters where the correlation effects are also observed. 相似文献
87.
Jaume Aguadé 《Mathematische Zeitschrift》1981,177(2):289-296
88.
Maspoch D Domingo N Ruiz-Molina D Wurst K Hernández JM Vaughan G Rovira C Lloret F Tejada J Veciana J 《Chemical communications (Cambridge, England)》2005,(40):5035-5037
A metal-organic open-framework with an unprecedented (6,3)-helical topology, large channels and mixed ferro- and antiferromagnetic interactions has been synthesized using a three-connecting tricarboxylic polychlorotriphenylmethyl radical and Co(ii) ions. 相似文献
89.
We prove the existence of transversal homoclinic points in the collinear three-body problem, restricted and general, and in the planar circular restricted three-body problem. As a consequence the shift of Bernoulli is proved to be included as a subsystem of a suitable section of the flow for the three cases studied. Then the existence of all the possible types of final evolution follows. 相似文献
90.
Cavallini M Gomez-Segura J Albonetti C Ruiz-Molina D Veciana J Biscarini F 《The journal of physical chemistry. B》2006,110(24):11607-11610
We report a new patterning process which takes place as a result of demixing of a binary polymer/solute mixture. An efficient, sustainable approach for ordering nanosized rings of so-called single molecule magnets (SMMs) is thus provided. It exploits the self-organization process in which SMM patterned film evolves to a spatially correlated pattern of nanosized rings. At long time, the anisotropic patterning of the film drives the ring to coalesce, into parallel lines of nanometric width. 相似文献