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141.
Maria Michaela Porzio Flavia Smarrazzo Alberto Tesei 《Archive for Rational Mechanics and Analysis》2013,210(3):713-772
Initial value problems for quasilinear parabolic equations having Radon measures as initial data have been widely investigated, looking for solutions which for positive times take values in some function space. In contrast, it is the purpose of this paper to define and investigate solutions that for positive times take values in the space of the Radon measures of the initial data. We call such solutions measure-valued, in contrast to function-valued solutionspreviously considered in the literature. We first show that there is a natural notion of measure-valued solution of problem (P) below, in spite of its nonlinear character. A major consequence of our definition is that, if the space dimension is greater than one, the concentrated part of the solution with respect to the Newtonian capacity is constant in time. Subsequently, we prove that there exists exactly one solution of the problem, such that the diffuse part with respect to the Newtonian capacity of the singular part of the solution (with respect to the Lebesgue measure) is concentrated for almost every positive time on the set where “the regular part (with respect to the Lebesgue measure) is large”. Moreover, using a family of entropy inequalities we demonstrate that the singular part of the solution is nonincreasing in time. Finally, the regularity problem is addressed, as we give conditions (depending on the space dimension, the initial data and the rate of convergence at infinity of the nonlinearity ψ) to ensure that the measure-valued solution of problem (P) is, in fact, function-valued. 相似文献
142.
Dr. Anil Reddy Marri Edoardo Marchini Dr. Valentin Diez Cabanes Dr. Roberto Argazzi Dr. Mariachiara Pastore Prof. Stefano Caramori Prof. Carlo Alberto Bignozzi Dr. Philippe C. Gros 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(65):16260-16269
A series of six new Fe(II)NHC-carboxylic sensitizers with their ancillary ligand decorated with functions of varied electronic properties have been designed with the aim to increase the metal-to- surface charge separation and light harvesting in iron-based dye-sensitized solar cells (DSSCs). ARM130 scored the highest efficiency ever reported for an iron-sensitized solar cell (1.83 %) using Mg2+ and NBu4I-based electrolyte and a thick 20 μm TiO2 anode. Computational modelling, transient absorption spectroscopy and electrochemical impedance spectroscopy (EIS) revealed that the electronic properties induced by the dimethoxyphenyl-substituted NHC ligand of ARM130 led to the best combination of electron injection yield and spectral sensitivity breadth. 相似文献
143.
Treatment of benzofuroxan derivatives with ferrous sulphate in DMSO/water solution affords in high yield o-nitroanilines. o-Nitroaniline was also obtained by reduction of benzofuroxan with thiophenol in presence of catalytic amount of Fe2+ or Fe3+ salts. 相似文献
144.
Jessica Walkenhorst Umberto De Giovannini Alberto Castro Angel Rubio 《The European Physical Journal B - Condensed Matter and Complex Systems》2016,89(5):128
Recent advances in laser technology allow us to follow electronic motion at its natural time-scale with ultra-fast time resolution, leading the way towards attosecond physics experiments of extreme precision. In this work, we assess the use of tailored pumps in order to enhance (or reduce) some given features of the probe absorption (for example, absorption in the visible range of otherwise transparent samples). This type of manipulation of the system response could be helpful for its full characterization, since it would allow us to visualize transitions that are dark when using unshaped pulses. In order to investigate these possibilities, we perform first a theoretical analysis of the non-equilibrium response function in this context, aided by one simple numerical model of the hydrogen atom. Then, we proceed to investigate the feasibility of using time-dependent density-functional theory as a means to implement, theoretically, this absorption-optimization idea, for more complex atoms or molecules. We conclude that the proposed idea could in principle be brought to the laboratory: tailored pump pulses can excite systems into light-absorbing states. However, we also highlight the severe numerical and theoretical difficulties posed by the problem: large-scale non-equilibrium quantum dynamics are cumbersome, even with TDDFT, and the shortcomings of state-of-the-art TDDFT functionals may still be serious for these out-of-equilibrium situations. 相似文献
145.
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147.
By establishing a comparison result and using the monotone iterative technique combined with the method of upper and lower solutions, we investigate the existence of solutions for systems of nonlinear fractional differential equations. 相似文献
148.
Rubén Cordero Miguel Cruz Alberto Molgado Efraín Rojas 《General Relativity and Gravitation》2014,46(7):1-20
In this paper we study the late evolution of Relic Gravitational Waves in coupled dark energy models, where dark energy interacts with cold dark matter. Relic Gravitational Waves are second tensorial order perturbations of the Lemaitre–Friedman–Robertson–Walker metric and experiment an evolution ruled by the scale factor of the metric. We find that the amplitude of Relic Gravitational Waves is smaller in coupled dark energy models than in models with non interacting dark energy. We also find that the amplitude of the waves predicted by the models with coupling term proportional to the dark energy density is smaller than those of the models with coupling term proportional to dark matter density. 相似文献
149.
Dr. Peter Wick Dr. Anna E. Louw‐Gaume Dr. Melanie Kucki Prof. Harald F. Krug Prof. Kostas Kostarelos Prof. Bengt Fadeel Prof. Kenneth A. Dawson Dr. Anna Salvati Prof. Ester Vázquez Dr. Laura Ballerini Dr. Mauro Tretiach Dr. Fabio Benfenati Dr. Emmanuel Flahaut Dr. Laury Gauthier Prof. Maurizio Prato Dr. Alberto Bianco 《Angewandte Chemie (International ed. in English)》2014,53(30):7714-7718