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排序方式: 共有453条查询结果,搜索用时 62 毫秒
41.
In this paper, we propose a new general method to compute rigorously global smooth branches of equilibria of higher-dimensional
partial differential equations. The theoretical framework is based on a combination of the theory introduced in Global smooth solution curves using rigorous branch following (van den Berg et al., Math. Comput. 79(271):1565–1584, 2010) and in Analytic estimates and rigorous continuation for equilibria of higher-dimensional PDEs (Gameiro and Lessard, J. Diff. Equ. 249(9):2237–2268, 2010). Using this method, one can obtain proofs of existence of global smooth solution curves of equilibria for large (continuous)
parameter ranges and about local uniqueness of the solutions on the curve. As an application, we compute several smooth branches
of equilibria for the three-dimensional Cahn–Hilliard equation. 相似文献
42.
43.
Hardelauf H Sisnaiske J Taghipour-Anvari AA Jacob P Drabiniok E Marggraf U Frimat JP Hengstler JG Neyer A van Thriel C West J 《Lab on a chip》2011,11(16):2763-2771
Spatially defined neuronal networks have great potential to be used in a wide spectrum of neurobiology assays. We present an original technique for the precise and reproducible formation of neuronal networks. A PDMS membrane comprising through-holes aligned with interconnecting microchannels was used during oxygen plasma etching to dry mask a protein rejecting poly(ethylene glycol) (PEG) adlayer. Patterns were faithfully replicated to produce an oxidized interconnected array pattern which supported protein adsorption. Differentiated human SH-SY5Y neuron-like cells adhered to the array nodes with the micron-scale interconnecting tracks guiding neurite outgrowth to produce neuronal connections and establish a network. A 2.0 μm track width was optimal for high-level network formation and node compliance. These spatially standardized neuronal networks were used to analyse the dynamics of acrylamide-induced neurite degeneration and the protective effects of co-treatment with calpeptin or brain derived neurotrophic factor (BDNF). 相似文献
44.
The structure and absolute configuration of natural 8-epi-9-deoxygoniopypyrone have been confirmed by an efficient and highly diastereoselective synthesis in 15 steps from (S)-mandelic acid with an overall yield of 43%. 相似文献
45.
Nathalie Deruelle Jean-Philippe Uzan 《International Journal of Theoretical Physics》1997,36(11):2461-2468
We briefly recall the problem of defining conserved quantities such as energy in general relativity, and the solution given
by introducing a symmetric background. We apply the general formalism to perturbed Robertson-Walker spacetimes with de Sitter
geometry as background. We relate the obtained conserved quantities to Traschen's integral constraints and mention a few applications
in cosmology. 相似文献
46.
L. A. Hamel L. Lessard H. Jeremie J. Chauvin 《Zeitschrift für Physik A Hadrons and Nuclei》1985,321(3):439-441
The beta decay rate of the16N(0?; 120keV) →16O(0+, G.S.) transition has been remeasured. Our result (Λ β =0.48±0.024 s?1) is in excellent agreement with a previous measurement but strongly disagrees with another experimental value. The two agreeing results provide an experimental verification of the importance of meson exchange currents in 0+-0? weak transitions. A value ofg p/g A~11–12 can be inferred from the correspondingΛ μ rate. 相似文献
47.
A. Champagne G. Beaudoin L. A. Hamel H. Jeremie L. Lessard 《Zeitschrift für Physik A Hadrons and Nuclei》1988,330(4):377-385
We have measured the beta spectrum of the 0?(120 keV,t 1/2=5.25 μs) state of16N. The response function of our detector has been measured, parameterized and then fitted to known spectral shapes taken under conditions close to those in the actual experiment. Using this response function and subtracting a 56 μs half-life background due to neutron capture in the detector, the measured 0? spectrum compares well with the allowed shape for the 0?→0+ spectrum plus a small contribution from the allowed 0?→1? transition. 相似文献
48.
Jean-Philippe Rocher Mohammed Ahmar Joelle Paris 《Journal of heterocyclic chemistry》1988,25(2):599-601
Condensation of dimethyl 3-methylglutaconate with ketones provides a one pot route for the preparation of 5-methoxycarbonyl-4-methyldihydropyran-2-ones. The experimental conditions to give selectively pyran-2-ones isomers are discussed. The structure of the different products was established on the basis of 1H and 13C nmr spectral data. 相似文献
49.
We show that pointlike defect model of glasses cannot explain the thermodynamic properties of glass formers, as for example, the excess specific heat close to the glass transition, contrary to the claim of Garrahan and Chandler [Proc. Natl. Acad. Sci. U.S.A. 100, 9710 (2003)]. More general models and approaches in terms of extended defects are also discussed. 相似文献
50.
Phuoc KT Corde S Shah R Albert F Fitour R Rousseau JP Burgy F Mercier B Rousse A 《Physical review letters》2006,97(22):225002
We demonstrate that betatron x-ray radiation accurately provides direct imaging of electrons trajectories accelerated in laser wakefields. Experimental far field x-ray beam profiles reveal that electrons can follow similar transverse trajectories with typical excursions of 1.5 microm+/-0.5 microm in the plane of laser polarization and 0.7 microm+/-0.2 microm in the plane perpendicular. 相似文献