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71.
González-Rojas C. H. Oprunenko Yu. F. Morales R. G. E. 《Russian Chemical Bulletin》2004,53(2):474-475
A method for the synthesis of diphenylacetylenes containing donor and acceptor groups in aryl substituents was proposed. 4"-Formyl-4-methoxydiphenylacetylene was synthesized as an example. 相似文献
72.
A particle-in-cell code is used to investigate the evolution of a density plume moving through a background plasma with supersonic speed directed along the confinement magnetic field. For scale lengths representative of laboratory and auroral phenomena, the major nonlinear effects identified by the present simulations are the formation of a bipolar current system from the ballistic electrons, the appearance of transient potential layers, and the carving of deep density cavities. A 3D magnetic topology is generated by the self-consistent ballistic and diamagnetic currents that accompany highly localized potential layers. 相似文献
73.
Walsh RD Bradner MW Fleischman aS Morales LA Moulton aB Rodríguez-Hornedo N Zaworotko MJ 《Chemical communications (Cambridge, England)》2003,(2):186-187
The carboxylic acid-pyridine supramolecular heterosynthon can be exploited to predictably generate binary crystalline phases involving rac-ibuprofen, rac-flurbiprofen or aspirin. 相似文献
74.
C. A. Morales 《Transactions of the American Mathematical Society》2003,355(2):735-745
Let be an Axiom A flow with a transverse torus exhibiting a unique orbit that does not intersect . Suppose that there is no null-homotopic closed curve in contained in either the stable or unstable set of . Then we show that has either an attracting periodic orbit or a repelling periodic orbit or is transitive. In particular, an Anosov flow with a transverse torus is transitive if it has a unique periodic orbit that does not intersect the torus.
75.
Let (X, F) be an Alexandroff space, let A(F) be the Boolean subalgebra of 2
X
generated by F, let G be a Hausdorff commutative topological lattice group and let rbaF(A(F), G) denote the set of all order bounded F-inner regular finitely additive set functions from A(F) into G. Using some special properties of the elements of rbaF(A(F), G), we extend to this setting the first decomposition theorem of Alexandroff. 相似文献
76.
Mui Siang Soh Sonsoles Amor Garcia Santamaria Evan Laurence Williams Marta Pérez‐Morales Henk J. Bolink Alan Sellinger 《Journal of Polymer Science.Polymer Physics》2011,49(7):531-539
A new class of solution processable dendrimers based on cyclic phosphazene (CP) cores have been prepared and used as host materials for blue and green organic light emitting diodes (OLEDs). The dendrimers are prepared in high yield from minimal step reactions, are soluble in common solvents for solution processing, are amorphous, and have excellent thermal properties necessary for application in OLEDs. OLED efficiencies of 10.3 cd/A (4.2 lm/W) and 35.3 cd/A (33.5 lm/W) were achieved using commercially available FIrpic and Ir(mppy)3 as blue and green phosphorescent emitters, respectively. These efficiencies were 2× higher than control devices prepared using poly(N‐vinylcarbazole), the most commonly used host material in solution processed phosphorescent OLEDs. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011 相似文献
77.
Jorge Bustamante José M. Quesada Lorena Morales de la Cruz 《Journal of Approximation Theory》2010,162(8):1495-1508
We present direct theorems for some sequences of positive linear operators in weighted spaces. The results, given in terms of some Ditzian–Totik moduli of smoothness, include estimations in norms and Becker type estimations. 相似文献
78.
A J Conejo F J Nogales M Carrión J M Morales 《The Journal of the Operational Research Society》2010,61(2):235-245
Organized trading for electricity includes both the pool and the futures market. Pool prices are volatile while the prices of the futures-market products are comparatively more stable. Thus, futures-market products constitute hedging instruments to reduce the risk suffered by any market agent. Electricity market agents engage in both pool and futures market transactions seeking to maximize their respective profits/utilities for a given risk level on profit variability. To make informed decisions, the market agent must gather as much accurate information as possible on the pool prices covering the whole time horizon spanned by the futures-market product. This paper provides a novel technique to represent conveniently the uncertainty associated with pool prices during long- or medium-term horizons through a set of scenarios, that is, pool price realizations. The proposed technique uses the prices of the futures-market products as long-term explanatory variables and exploits the short-term structure of the pool prices. 相似文献
79.
M. S. Batista M. A. Morales E. Baggio-Saitovich E. A. Urquieta-González 《Hyperfine Interactions》2001,134(1):161-166
The Fe species present in Fe/ZSM-5 catalysts prepared by ionic exchange in aqueous solution or in the solid state are investigated. The samples were characterized by XRD, EPR, Mössbauer Spectroscopy (MOS-S) and chemical analysis. XRD showed that the peak intensity decreased with the increase in Fe content in the samples. EPR and MOS-S showed that the Fe atoms in all the activated samples appear as Fe+3, independently of the method used in the catalyst preparation. The MOS-S data also showed that Fe/ZSM-5, prepared by ion exchange in the solid state presented lower hematite content and more Fe species in charge-compensation sites, the responsible for the catalytic activity, as confirmed by the behavior in the propane oxidation. 相似文献
80.
Jorge Antonio Guerrero‐Álvarez Wendy Paloma Mas‐Ku Cesar Garcías‐Morales Armando Ariza‐Castolo 《Magnetic resonance in chemistry : MRC》2010,48(5):356-361
The relative acidities of the cis and trans isomers of a series of 1,5‐oxazaspiro[5.5]undecane derivatives were determined by measuring ΔpK in acid‐base titrations followed by 1 H NMR. Relative structural stabilities were determined by measuring substituent chemical shift and γ‐gauche effects in 13C, 15N, and 17O NMR. Crystallographic characterization of a model spiro[5.5]undecane is presented to support the basicity in solid state. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献