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991.
992.
Antonio R. Cano-Marín 《Tetrahedron》2005,61(2):395-400
The synthesis of first- and second-generation dendrimers bearing phenylenevinylene chromophores within the dendritic branches (stilbenoid dendrimers) and polyenes (3 and 5 double bonds) as cores is described. A preliminary study of the optical properties of the resulting compounds was conducted by UV/vis and fluorescence spectroscopy. 相似文献
993.
Antonio Jiménez-Martínez 《International Journal of Game Theory》2006,34(3):425-442
We propose a two-person game-theoretical model to study information sharing decisions at an interim stage when information is incomplete. The two agents have pieces of private information about the state of nature, and that information is improved by combining the pieces. Agents are both senders and receivers of information. There is an institutional arrangement that fixes a transfer of wealth from an agent who lies about her private information. In our model, we show that (1) there is a positive relation between information revelation and the amount of the transfers, and (2) information revelation has a collective action structure, in particular, the incentives of an agent to reveal decrease with respect to the amount of information disclosed by the other. 相似文献
994.
Let X be a separable superreflexive Banach space with a Schauder basis. We prove the existence of an equivalent uniformly smooth
(resp. uniformly rotund) renorming under which the given basis is monotone.
First author supported by the grants MTM2005-08379 of MECD (Spain), 00690/PI/04 of Fundación Séneca (CARM, Spain) and AP2003-4453
of MECD (Spain), Second author supported by AV0Z10190503 and A100190502. 相似文献
995.
This paper studies the existence of bounded solutions of a forced non-linear differential equation of arbitrary order. Necessary and sufficient conditions for the existence of such solutions are obtained. These results are inspired by classical results on the periodic problem, both in the resonant and non-resonant cases.
996.
In this paper we study existence and multiplicity results of geodesics joining two given events in Lorentzian manifolds with
lack of geodesic completeness. The considered Lorentzian manifolds are not necessarily static or stationary and satisfy a
condition of convexity on the boundary.
work supported by M.U.R.S.T. research founds 40%–60% 1992 相似文献
997.
998.
Gleison Antonio Casagrande Ernesto Schulz Lang Prof. Dr. Bárbara Tirloni Robert Alan Burrow Gelson Manzoni de Oliveira Sebastião S. Lemos 《无机化学与普通化学杂志》2006,632(5):893-896
A three‐step one‐pot synthetic procedure to synthesize the neutral tellurium(IV) coordination compounds PhTeX3L (X = Br, I and L = ethylenethiourea) has been developed and is described in this article. Oxidative halogenation of PhTeTePh in methanol generates the tellurium(II) derivative, PhTeX, which is subsequently complexed with ethylenethiourea, and, finally, further oxidative addition of additional halogen affords the corresponding tellurium(IV) compound PhTeX3L in good yields. The final product was obtained by the slow evaporation of the reaction mixture as black crystals. The X‐ray structural analyses of the compounds show Te···X and X···X secondary interactions in the solid state and suggest a weak dependence of the formation of supramolecular assemblies on the nature of the halogen bonded to the tellurium atom. 相似文献
999.
Marquina's approximate Riemann solver for the compressible Euler equations for gas dynamics is generalized to an arbitrary equilibrium equation of state. Applications of this solver to some test problems in one and two space dimensions show the desired accuracy and robustness. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
1000.
Boris V. Kapitonov Marco Antonio Raupp 《Mathematical Methods in the Applied Sciences》2001,24(4):193-207
This paper considers transmission problem for the system of electromagneto‐elasticity having piecewise constant coefficients in a bounded domain. The result on exact boundary controllability is obtained provided the interfaces, where the coefficients have a jump discontinuity, are all star‐shaped with respect to one and the same point and the coefficients satisfy a certain monotonicity conditions. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献