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991.
992.
Chen Z Neukermans S Wang X Janssens E Zhou Z Silverans RE King RB Schleyer Pv Lievens P 《Journal of the American Chemical Society》2006,128(39):12829-12834
General principles for designing stable highly symmetrical clusters are proposed. This approach takes advantage of both the extra stability of cage aromaticity and the good geometrical balance between the outer cage and the endohedral atom. The applicability of these design principles was confirmed by gas-phase experimental observations on group 14 element cages with endohedral Al's and also is illustrated by many literature examples of diverse systems. 相似文献
993.
This article is devoted to an extensive study of an infinite-dimensional Lie algebra
, introduced in [14] in the context of non-equilibrium statistical physics, containing as subalgebras both the Lie algebra
of invariance of the free Schr?dinger equation and the central charge-free Virasoro algebra Vect(S1). We call
the Schr?dinger-Virasoro Lie algebra. We study its representation theory: realizations as Lie symmetries of field equations, coadjoint representation, coinduced
representations in connection with Cartan’s prolongation method (yielding analogues of the tensor density modules for Vect(S1)). We also present a detailed cohomological study, providing in particular a classification of deformations and central extensions;
there appears a non-local cocycle.
Communicated by Petr Kulish
Daniel Arnaudon, in memoriam
Submitted: January 17, 2006; Accepted: March 21, 2006 相似文献
994.
995.
Schepens W Van Haver D Vandewalle M Bouillon R Verstuyf A De Clercq PJ 《Organic letters》2006,8(19):4247-4250
A novel series of analogues of calcitriol (1) is developed featuring a spirocyclic central core resulting from C18/C21-connection and C15/C16-deletion (2a, 2b). The synthesis of the key intermediate involves an Eschenmoser rearrangement of an enantiomerically pure bromo-substituted cyclohexenol. 相似文献
996.
Grant JA Haigh JA Pickup BT Nicholls A Sayle RA 《Journal of chemical information and modeling》2006,46(5):1912-1918
We apply a recently published method of text-based molecular similarity searching (LINGO) to standard data sets for the purpose of quantifying the accuracy of the approach. Our implementation is based on a pattern-matching finite state machine (FSM) which results in fast search times. The accuracy of LINGO is demonstrated to be comparable to that of a path-based fingerprint and offers a simple yet effective method for similarity searching. 相似文献
997.
[Structure: see text] 2-morpholin-4-yl-4-oxo-4H-chromen-8-yl 2,2,2-trifluoromethanesulfonate is a key intermediate for the synthesis of the DNA-dependent protein kinase (DNA-PK) inhibitor 8-dibenzothiophen-4-yl-2-morpholin-4-yl-chromen-4-one (NU7441). Two improved methods for the synthesis of this triflate have been developed: (A) in 35% overall yield, through modification of the published route, and (B) in 15% overall yield, by a new route employing a Baker-Venkataraman rearrangement to enable generation of the chromenone scaffold. Both syntheses depend on the judicious use of allyl protecting groups. 相似文献
998.
We give necessary and sufficient conditions for a nonexpansive map on a finite-dimensional normed space to have a nonempty, bounded set of fixed points. Among other results we show that if f: V → V is a nonexpansive map on a finite-dimensional normed space V, then the fixed point set of f is nonempty and bounded if and only if there exist w1,..., w m in V such that {f(w i ) ? w i : i = 1,..., m} illuminates the unit ball. This yields a numerical procedure for detecting fixed points of nonexpansive maps on finite-dimensional spaces. We also discuss applications of this procedure to certain nonlinear eigenvalue problems arising in game theory and mathematical biology. 相似文献
999.
Motivated by the study of self-cleaning surfaces, the interaction between a spherical solid particle and a water droplet is studied on the microsale level, in terms of the balance forces and the surface properties. To define the forces acting on the solid-liquid interface, the meniscus depression is computed from the Young-Laplace equation, using a non-linear finite element formulation. The equilibrium force is derived in terms of the contact angle, particle size, and the penetration. (© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
1000.
Fabio Bellini Roger J. A. Laeven Emanuela Rosazza Gianin 《Mathematics and Financial Economics》2018,12(1):5-32
In this paper we provide an axiomatic foundation to Orlicz risk measures in terms of properties of their acceptance sets, by exploiting their natural correspondence with shortfall risk Föllmer and Schied (Stochastic finance. De Gruyter, Berlin, 2011), thus paralleling the characterization in Weber (Math Financ 16:419–442, 2006). From a financial point of view, Orlicz risk measures assess the stochastic nature of returns, in contrast to the common use of risk measures to assess the stochastic nature of a position’s monetary value. The correspondence with shortfall risk leads to several robustified versions of Orlicz risk measures, and of their optimized translation invariant extensions (Rockafellar and Uryasev in J Risk 2:21–42, 2000, Goovaerts et al. in Insur Math Econ 34:505–516, 2004), arising from an ambiguity averse approach as in Gilboa and Schmeidler (J Math Econ 18:141–153, 1989), Maccheroni et al. (Econometrica 74:1447–1498, 2006), Chateauneuf and Faro (J Math Econ 45:535–558, 2010), or from a multiplicity of Young functions. We study the properties of these robust Orlicz risk measures, derive their dual representations, and provide some examples and applications. 相似文献