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A.V. Silhanek R.G.B. Kramer J. Van de Vondel V.V. Moshchalkov M.V. Miloševi? G.R. Berdiyorov F.M. Peeters R.F. Luccas T. Puig 《Physica C: Superconductivity and its Applications》2010,470(19):726-729
We demonstrate experimentally and theoretically that the dissipative state at high current densities of superconducting samples with a periodic array of holes consist of flux rivers resulting from a short range attractive interaction between vortices. This dynamically induced vortex–vortex attraction results from the migration of quasiparticles out of the vortex core. We have directly visualized the formation of vortex chains by scanning Hall microscopy after freezing the dynamic state by a field cooling procedure at constant bias current. Similar experiments carried out in a sample without holes show no hint of flux river formation. 相似文献
444.
Dorothe Bardiot Helmut Rosemeyer Eveline Lescrinier Jef Rozenski Arthur VanAerschot Piet Herdewijn 《Helvetica chimica acta》2005,88(12):3210-3224
Cyclohexyl nucleosides with an adenine and uracil base have been synthesized from 2‐azidocyclohexane‐1,5‐diol. The obtained racemic nucleosides were resolved using (R)‐O‐methylmandelic acid. Short oligonucleotides were synthesized using phorphoramidite chemistry. However, these oligonucleotides do not show self‐hybridization, and duplexes are less stable than those of ribopyranosyl‐(4′ → 2′)‐oligonucleotides. 相似文献
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446.
In this paper we consider discrete time forward interest rate models. In our approach, unlike in the classical Heath–Jarrow–Morton
framework, the forward rate curves are driven by a random field. Hence we get a general interest rate structure. Our aim is
to give an overview of our results in such a model on the following questions: no-arbitrage conditions, maximum likelihood
estimation of the volatility, as well as the joint estimation of the parameters and the asymptotic behaviour of the estimators,
relationship with continuous models. Finally we give discussion on the practical problems of the estimation and we show several
numerical results on the statistics of such models.
This research has been supported by the Hungarian Scientific Research Fund under Grants No. OTKA–F046061/2004 and OTKA–T048544/2005. 相似文献
447.
Helmuth Peeters Thierry Verbiest Guy Koeckelberghs 《Journal of polymer science. Part A, Polymer chemistry》2009,47(7):1891-1900
The synthesis, aggregation, and optical properties of a chiral, regioregular polythiophene, substituted with a conjugated substituent, are described. The polymer was prepared using a Stille coupling reaction. The fact that the side‐chain contributes to the absorption (UV‐vis), emission (fluorescence), and redox behavior (cyclic voltammetry) of the material demonstrates that the substituent contributes to the electronic properties. It was shown that the conjugated side‐chain chirally stacks in conditions in which the polymer backbone aggregates, which demonstrates the ability of conjugated polymers to induce a (chiral) lamellar organization of conjugated moieties, present in their side‐chain. The aggregation of both the side‐chain and the backbone was monitored using UV‐vis and CD spectroscopy. Finally, it is shown that the conjugated side‐chain can selectively be oxidized, without oxidizing the polythiophene backbone. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1891–1900, 2009 相似文献
448.
Angel Dago Morales Hctor Novoa de Armas Norbert M. Blaton Oswald M. Peeters Camiel J. De Ranter Heidy Mrquez Ramn Poms Hernndez 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(4):503-504
The title compound, C13H18N2O2S, crystallizes in the thioamidic form. The molecules are connected by N—H?S interactions forming dimers with N?S and H?S distances of 3.487 (4) and 2.76 Å, respectively. 相似文献
449.
The properties of a capacitive HF discharge with growing nanoparticles are studied with the use of kinetic PIC-MCC simulation. At the initial stage of growth, the nanoparticles are shown to be localized at the interface between the near-electrode layer and quasi-neutral plasma, where the rate of ionization by electron impact has the maximum value. At the beginning of formation of particles, plasma parameters change rapidly and a transition between the capacitive and spatial discharge burning modes is observed for a certain critical size of the particles. If the growth of the dust particles continues, their distribution over the discharge becomes more uniform and the steady-state parameters of the gas-discharge plasma hardly change. 相似文献
450.