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271.
Raul SanMartin Blanca Inés María Jesús Moure María Teresa Herrero Esther Domínguez 《Helvetica chimica acta》2012,95(6):955-962
The catalytic activity of two CNC palladium pincer complexes is evaluated in two fundamental C? C bond‐forming reactions: Mizoroki? Heck and Sonogashira cross‐couplings. After several optimization attempts and a brief comparison with a PCN pincer catalyst, a number of arylated alkenes and diarylethynes are synthesized by procedures based on the catalytic use of the above mentioned CNC Pd pincers in H2O and DMF. 相似文献
272.
López-Castro JD Delgado JJ Perez-Omil JA Gálvez N Cuesta R Watt RK Domínguez-Vera JM 《Dalton transactions (Cambridge, England : 2003)》2012,41(4):1320-1324
An electron microscopy study, in combination with modeling and image simulation, of four different reconstituted ferritin samples: recombinant human H and L homopolymers, and H and L heteropolymers of native L-subunit-rich horse spleen and H-subunit-rich human heart ferritins, points out the existence of a correlation between iron core shape and protein shell. 相似文献
273.
The concepts of substantive beliefs and derived beliefs are defined, a set of substantive beliefs S like open set and the neighborhood of an element substantive belief. A semantic operation of conjunction is defined with a structure of an Abelian group. Mathematical structures exist such as poset beliefs and join‐semilattttice beliefs. A metric space of beliefs and the distance of belief depending on the believer are defined. The concepts of closed and opened ball are defined. S′ is defined as subgroup of the metric space of beliefs Σ and S′ is a totally limited set. The term s is defined (substantive belief) in terms of closing of S′. It is deduced that Σ is paracompact due to Stone's Theorem. The pseudometric space of beliefs is defined to show how the metric of the nonbelieving subject has a topological space like a nonmaterial abstract ideal space formed in the mind of the believing subject, fulfilling the conditions of Kuratowski axioms of closure. To establish patterns of materialization of beliefs we are going to consider that these have defined mathematical structures. This will allow us to understand better cultural processes of text, architecture, norms, and education that are forms or the materialization of an ideology. This materialization is the conversion by means of certain mathematical correspondences, of an abstract set whose elements are beliefs or ideas, in an impure set whose elements are material or energetic. Text is a materialization of ideology. © 2013 Wiley Periodicals, Inc. Complexity 19: 46–62, 2013 相似文献
274.
Catalina Domínguez Ernst P. Stephan Matthias Maischak 《Numerical Methods for Partial Differential Equations》2012,28(5):1417-1439
In this article, we establish a hierarchical a posteriori error estimate for a coupling of finite elements and boundary elements for a fluid‐structure interaction problem posed in two and three dimensions. These methods combine boundary elements for the exterior fluid and finite elements for the elastic structure. We consider two weak formulations, a nonsymmetric one and a symmetric one, which are both uniquely solvable. We present the reliability and efficiency of the error estimates. For the two dimensional case, we compute local error indicators which allow us to develop an adaptive mesh refinement strategy on triangles. For the three dimensional case, we use hexahedrons as elements. Numerical experiments underline our theoretical results. © 2011 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2012 相似文献
275.
Rivera OM Torrado AM Moldes AB Domínguez JM 《Applied biochemistry and biotechnology》2009,152(2):262-274
This work deals with the nutritional evaluation of grape marc hydrolyzates as fermentation medium for Lactobacillus pentosus. Usually, the fermentation of xylose and arabinose in the presence of glucose remains a primary obstacle for economical biomass
conversion. The few microorganisms that can grow simultaneously on both pentose and hexose sugars contained in lignocellulosic
feedstocks typically grow slowly and demonstrate marginal yields and productivities. Moreover, lignocellulosic hydrolyzates
contain phenolic compounds and other components originated by the degradation of sugars that can inhibit lactic acid fermentation.
However, in this case, grape marc hydrolyzates not only did not need a detoxification stage, but it also improved the xylose
consumption by Lactobacillus pentosus with a faster and more efficient conversion of hemicellulosic sugars compared with synthetic media. After analysis of grape
marc hydrolyzates, it was observed that minerals such as K (2,707 mg/L), Ca (3,681 mg/L), and Mg (198.5 mg/L) are present
in higher concentration than those found in the general medium of Lactobacillus (1,705 mg/L of K, 58.3 mg/L of Ca, and 27.0 mg/L of Mg). Moreover, grape marc hydrolyzates contain an additional source of
nitrogen (9.2 g/L) which, together with their elevated mineral concentration, improved lactic acid fermentation compared with
synthetic media. 相似文献
276.
Armida Torreggiani Dr. Jordi Domènech Dr. Ruben Orihuela Dr. Carla Ferreri Dr. Sílvia Atrian Prof. Mercè Capdevila Prof. Chryssostomos Chatgilialoglu Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(24):6015-6024
Biomimetic tandem protein/lipid damage : The reactions of reductive reactive species, produced by γ irradiation of water, with Zn and Cd complexes of a metallothionein from a plant afford diffusible sulfur‐centred radicals generated from methionine residues and sulfide ligands. These species migrate from the aqueous phase to the lipid bilayer and transform the cis double bond of the oleate moiety to trans isomer (see scheme).
277.
Fluctuating hydrodynamics is used to describe the total energy fluctuations of a freely evolving gas of inelastic hard spheres near the threshold of the clustering instability. They are shown to be governed only by vorticity fluctuations that also lead to a renormalization of the average total energy. The theory predicts a power-law divergent behavior of the scaled second moment of the fluctuations, and a scaling property of their probability distribution, both in agreement with simulations results. A more quantitative comparison between theory and simulation for the critical amplitudes and the form of the scaling function is also carried out. 相似文献
278.
An attempt has been made in order to unify the three types of solvatochromisms (negative, positive and inverted) of phenolate betaine dyes by a working model which describes them as particular cases of a general behavior. The model, based on the calculation (gas phase) of the chemical hardness of donor and acceptor fragments, was applied to 56 examples from the literature. As a result, the investigated compounds were grouped according to the sum of the hardnesses of their (non‐interacting) fragments, this sum being larger for a negative, intermediate for an inverted, and smaller for a positive solvatochromic behavior. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
279.
José R. Mora Alexis Maldonado Rosa M. Domínguez Gabriel Chuchani 《Journal of Physical Organic Chemistry》2010,23(9):845-852
The rates of gas‐phase elimination of several β‐substituted diethyl acetals have been determined in a static system and seasoned with allyl bromide. The reactions, inhibited with toluene, are homogeneous, unimolecular, and follow first‐order law kinetics. These elimination processes involve two parallel reactions. The first parallel reaction yields ethanol and the corresponding ethyl vinyl ether. The latter product is an unstable intermediate and further decomposes to ethylene and the corresponding substituted aldehyde. The second parallel reaction gives ethane and the corresponding ethyl ester. The kinetics has been measured over the temperature range of 370–441 °C and pressure range of 23–160 torr. The rate coefficients are given by the following Arrhenius equations: The differences in the rates of ethanol formation may be attributed to electronic transmission of the β‐substituent. The comparative kinetic and thermodynamic parameters of the parallel reactions suggest two different concerted polar four‐membered cyclic transition state types of mechanisms. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
280.
Raúl A. Rica Francisco Domínguez Manuel J. Gutiérrez Javier Bañuelos Jesús J. del Pozo Daniel Rodríguez 《The European physical journal. Special topics》2018,227(3-4):445-456
We report on the progress towards the implementation of a double trap system for the coupling of ion clouds stored in different traps through the charges they induce in a common electrode. The two traps have cylindrical symmetry and can be used either as Penning or Paul traps. The laser system for Doppler cooling of 40Ca+ clouds is described. The cooling can be performed differentially in the two traps, aiming at the study of the coupling between two clouds of ions at different temperatures. This setup is the starting point for the realization of energy transfer between two Doppler-cooled ions stored in different traps. We report on the status of the experiment and evaluate the performance required for an efficient coupling. 相似文献