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81.
Ana Dalia Pano-Azucena Jose de Jesus Rangel-Magdaleno Esteban Tlelo-Cuautle Antonio de Jesus Quintas-Valles 《Nonlinear dynamics》2017,87(4):2203-2217
The experimental realization of a chaotic secure communication system is introduced herein taking advantage of Arduino’s open source integrated development environment along with its preset functions that reduce development time and complexity. The system uses multi-directional multi-scroll chaotic oscillators that are based on piecewise-linear functions. Experimental results are given for chaos generators in 1-direction (1-D), 2-D and 3-D of up to 20, \(20\times 20\) and \(20\times 20\times 20\) scrolls, respectively. Using two chaos generators, a chaotic secure communication system is implemented in a master–slave topology by applying generalized Hamiltonian forms and observer approach. Finally, we detail experimental results for the synchronization of \(6\times 6\) and \(20\times 20\) scroll attractors, which are used for transmitting a monochromatic image through the Arduino-based chaotic secure communication system. 相似文献
82.
César Menor‐Salván Dr. Dra. Marta Ruiz‐Bermejo Marcelo I. Guzmán Dr. Susana Osuna‐Esteban Sabino Veintemillas‐Verdaguer Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(17):4411-4418
From urea to nucleobases : Freeze–thaw cycles in urea ( 1 ) solutions under methane/nitrogen atmospheres lead, with application of an energy source, to the synthesis of pyrimidines (mainly cytosine ( 2 ) and uracil ( 3 )), triazines (such as cyanuric acid ( 4 )), and adenine. This synthesis appears to be dependent on the atmosphere and the freezing conditions. At room temperature, hydantoin ( 5 ) is obtained. However, a freezing urea/water system subjected to an energy source under an inert atmosphere generates s‐triazines.
83.
84.
85.
Alfonso GonzálezAravind Dasari Berta HerreroEmeric Plancher Julio SantarénAntonio Esteban Szu-Hui Lim 《Polymer Degradation and Stability》2012,97(3):248-256
To understand and improve the fire retardancy behavior of polylactic acid, we have incorporated two structurally different additives, sepiolite and organically modified montmorillonite. A novel approach (combination of electrospinning and extrusion/injection molding) is employed to address critical issues like char enhancement as well as the homogeneity/uniformity of the inorganic barrier during combustion of polymer nanocomposites. Fundamental knowledge is gained on the mechanisms of fire retardancy, particularly with samples of different thicknesses (thermally thin versus thermally intermediate/thick). Volumetric imaging of the residues provided a deeper understanding of the formation or the evolution of the inorganic barrier. Considerable insight on the dependency of biodegradation on the environment (primarily) and on the compromising effect of high aspect ratio nanoparticles is also obtained. This knowledge has a broader scientific impact and is critical to design the new generation of eco-benign flame retardant and biodegradable polymer nanocomposites. 相似文献
86.
Jean Dolbeault Maria J. Esteban Eric Séré 《Calculus of Variations and Partial Differential Equations》2000,10(4):321-347
In this paper we give two different variational characterizations for the eigenvalues of H+V where H denotes the free Dirac operator and V is a scalar potential. The first one is a min-max involving a Rayleigh quotient. The second one consists in minimizing an
appropriate nonlinear functional. Both methods can be applied to potentials which have singularities as strong as the Coulomb
potential.
Received June 5, 1998 / Accepted June 11, 1999 相似文献
87.
Esteban R. Bornancini Ruben A. Alonso Roberto A. Rossi 《Journal of organometallic chemistry》1984,270(2):177-183
The reactions of elemental phosphorus, arsenic and antimony with sodium metal in liquid ammonia form “M?1“ species that react with haloarenes under irradiation to form symmetrical triaryl derivatives of these metals by the SRN1 mechanism in fair to good yields. Further reaction with sodium metal gives a derivative nucleophile (diarylphosphide and diarylarsenide ions) that reacts with another haloarene under irradiation to form unsymmetrical phosphines and arsines. 相似文献
88.
The anodic processes which occur at the mercury electrode in 2-mercaptoethanol solutions are studied by various polarographic techniques (d.c., a.c. and differential pulse), controlled-potential coulometry, cyclic voltammetry and differential capacity curves. Two steps are distinguished in the process: a one-electron charge transfer and a dismutation step leading to the formation of a mercury(II) mercaptide. The final product is isolated and analyzed. Differential-pulse polarography can be used to determine ?10?4 M 2-mercaptoethanol with a limit of M. 相似文献
89.
90.
E. A. Calzetta 《International Journal of Theoretical Physics》2004,43(3):767-799
The goal of this paper is to develop the formalism of the two-particle irreducible (2PI) (G. Baym (1962). Physical Review
127, 1391; H. D. Dahmen and G. Jona Lasino (1962). Nuovo Cimento A
52, 807; C. de Dominicis and P. Martin (1964). Journal of Mathematical Physics
5, 14; J. Luttinger and J. Ward (1960). Physical Review
118, 1417; B. Vanderheyden and G. Baym (1998). Journal of Statistical Physics
98, 843; B. Vanderheyden and G. Baym (2000). In Progress in Nonequilibrium Green's Functions, World Scientific, Singapore). (or Cornwall–Jackiw–Tomboulis (CJT) (J. Cornwall, R. Jackiw, and E. Tomboulis (1974). Physical Review D
10, 2428; U. Kraemmer and A. Rebhan (2004). Reports on Progress in Physics
67, 351; R. Norton and J. Cornwall (1975). Annals of Physics
91, 106) effective action (EA) in a way appropiate to its application to nonequilibrium gauge theories. We hope this review article will stimulate new work into this field. 相似文献