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131.
Kong J Chen CY Balsells-Padros J Cao Y Dunn RF Dolman SJ Janey J Li H Zacuto MJ 《The Journal of organic chemistry》2012,77(8):3820-3828
A highly efficient synthesis of Vaniprevir (MK-7009) has been accomplished in nine linear steps and 55% overall yield. The key features of this synthesis include a cost-effective synthesis of the isoindoline subunit and efficient construction of the 20-membered macrocyclic core of Vaniprevir (MK-7009) utilizing ring-closing metathesis technology. A high-performing ring-closing metathesis protocol has been achieved by simultaneous slow addition of the ruthenium catalyst (0.2 mol %) and the diene substrate at a concentration of 0.13 M. 相似文献
132.
Daniel Jaume Jordi Massó Alejandro Neme 《Mathematical Methods of Operations Research》2012,76(2):161-187
A multiple-partners assignment game with heterogeneous sales and multi-unit demands consists of a set of sellers that own a given number of indivisible units of potentially many different goods and a set of buyers who value those units and want to buy at most an exogenously fixed number of units. We define a competitive equilibrium for this generalized assignment game and prove its existence by using only linear programming. In particular, we show how to compute equilibrium price vectors from the solutions of the dual linear program associated to the primal linear program defined to find optimal assignments. Using only linear programming tools, we also show (i) that the set of competitive equilibria (pairs of price vectors and assignments) has a Cartesian product structure: each equilibrium price vector is part of a competitive equilibrium with all optimal assignments, and vice versa; (ii) that the set of (restricted) equilibrium price vectors has a natural lattice structure; and (iii) how this structure is translated into the set of agents?? utilities that are attainable at equilibrium. 相似文献
133.
Victor Vilarrasa Diogo Bolster Marco Dentz Sebastia Olivella Jesus Carrera 《Transport in Porous Media》2010,85(2):619-639
The injection of supercritical CO2 in deep saline aquifers leads to the formation of a CO2 plume that tends to float above the formation brine. As pressure builds up, CO2 properties, i.e. density and viscosity, can vary significantly. Current analytical solutions do not account for CO2 compressibility. In this article, we investigate numerically and analytically the effect of this variability on the position
of the interface between the CO2-rich phase and the formation brine. We introduce a correction to account for CO2 compressibility (density variations) and viscosity variations in current analytical solutions. We find that the error in
the interface position caused by neglecting CO2 compressibility is relatively small when viscous forces dominate. However, it can become significant when gravity forces
dominate, which is likely to occur at late times of injection. 相似文献
134.
Maria Minguet David B. Amabilino Klaus Wurst Jaume Veciana 《Monatshefte für Chemie / Chemical Monthly》2001,132(1):71-82
Summary. A new phenyl α-nitronyl nitroxide bearing a hydroxyl group at position 2 of the aromatic ring and a chiral methyl lactate
substituent at position 5 has been synthesized with the aim of combining the magnetic properties of this kind of radical with
the optical properties endowed by the chiral group. The optically active compound forms intramolecular hydrogen bonds between
the OH group and one of the NO groups and shows a large torsion angle between the two rings when compared with similar radicals
with no substituent in this position. Therefore, the optical properties are distinct. The optical and magnetic properties
of the new radical in both solution and solid state are presented.
Received June 23, 2000. Accepted (revised) September 18, 2000 相似文献
135.
Jaume Llibre Paulo R. da Silva Marco A. Teixeira 《Journal of Dynamics and Differential Equations》2012,24(1):1-12
In this article we establish an interaction between non-smooth systems, geometric singular perturbation theory and synchronization phenomena. We find conditions for a non-smooth vector fields be locally synchronized. Moreover its regularization provide a singular perturbation problem with attracting critical manifold. We also state a result about the synchronization which occurs in the regularization of the fold-fold case. We restrict ourselves to the 3-dimensional systems (ℓ = 3) and consider the case known as a T-singularity. 相似文献
136.
137.
138.
Joan Cecilia Josep Galceran Jos Salvador Jaume Puy Francesc Mas 《International journal of quantum chemistry》1994,51(6):357-367
The use of both the Laplace transformation technique and the finite element method has been analyzed in an electrochemical system. The diffusion-controlled adsorption process of a species onto an electrode surface is studied in detail. © 1994 John Wiley & Sons, Inc. 相似文献
139.
Jaume Giné 《Journal of Mathematical Analysis and Applications》2006,324(1):739-745
In this note we give a family of planar polynomial differential systems with a prescribed hyperbolic limit cycle. This family constitutes a corrected and wider version of an example given in the work [M.A. Abdelkader, Relaxation oscillators with exact limit cycles, J. Math. Anal. Appl. 218 (1998) 308-312]. The result given in this note may be used to construct models of Liénard differential equations exhibiting a desired limit cycle. 相似文献
140.
Jaume Haro 《International Journal of Theoretical Physics》2007,46(4):951-971
The energy of the evolved vacuum state is calculated. From a frequency cut-off regularisation the divergent terms are separated
and, in the 1 + 1 dimensional case they are removed with a mass renormalisation of the moving boundary. A renormalisation
of the external force is also needed in 3 + 1 dimensions.
PACS Subject Classifications: 42.50.Lc, 03.70.+k, 11.10.Ef. 相似文献