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91.
92.
Juan C. Piña Miguel A. ZorroClécio C. de Souza Silva 《Physica C: Superconductivity and its Applications》2010,470(19):762-765
The formation of vortex–antivortex states in a superconducting film with a square array of magnetic dipoles magnetized perpendicularly to the film is investigated in the framework of the time-dependent Ginzburg–Landau equations. It is shown that a possible route to obtain equilibrium states is obtained following an experimentally realizable field-cooling procedure. The states thus obtained demonstrate a rich variety of phases, depending on magnetic moment intensity and dipole array-to-superconducting film distance. For instance, in the region of the phase diagram where each dipoles is able to generate N = 2 vortex–antivortex pairs, the antivortices induced by the negative stray fields of the dipoles undergo two transitions before ultimately merging into doubly-quantized giant antivortices. For N = 4, a state consisting on a three-quanta giant vortex below each dipole and an interstitial vortex–antivortex molecule was observed. Such state is thermodynamically stable and is induced by the fourfold symmetry of the dipole array, similar to symmetry-induced vortex–antivortex molecules found in mesoscopic superconductors. 相似文献
93.
James Mc Laughlin Peter Zimmer 《Journal of Mathematical Analysis and Applications》2008,345(2):670-677
We prove a new Bailey-type transformation relating WP-Bailey pairs. We then use this transformation to derive a number of new 3- and 4-term transformation formulae between basic hypergeometric series. 相似文献
94.
线性空间偶的运动公式 总被引:1,自引:1,他引:0
本文研究了线性空间偶的运动公式.利用活动标架法.在获得相交线性空间偶的运动密度公式的基础上,得到一系列有关相交线性空间偶的运动公式. 相似文献
95.
96.
利用Clark定理,研究了一维p-Laplacian方程边值问题多解的存在性,得到了这类边值问题至少有n对非平凡解的充分条件. 相似文献
97.
Conductance data are reported for Ph4AsPic, Ph4PPic, Ph4SbPic, Hex4NPic, Bu4PPic, Et4NSbCl6 in propylene carbonate at 25°C in the concentration range 1×10–4 to 15×10–4 M. The data were analyzed by the Justice modification of the Fuoss-Hsia equation and all salts studied were found to be associated and to form solvent separated ion pairs. Application of the Barthel-Bjerrum model of ion association permitted calculation of the non coulombic portion of the potentials of mean force, W±. Ionic limiting equivalent conductances of six ions were calculated using known values of R4N+, and Pic– ions. Walden products of ions in propylene carbonate were examined in the light of modern ion mobility theories, including Boyd-Zwanzig, Hubbard-Onsager, and Hubbard-Kayser models of ion solvent interactions. 相似文献
98.
Johannes Smid 《Journal of polymer science. Part A, Polymer chemistry》2002,40(13):2101-2107
A brief overview of the role that Dr. Michael Szwarc has played in unraveling the mechanism of living anionic polymerization is presented. Emphasis is placed on the different ionic species that control the propagation reaction in ether-type solvents. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2101–2107, 2002 相似文献
99.
广义Stirling数偶的理论及应用 总被引:5,自引:2,他引:3
The object of this expository paper is to sum up several results concerning generalized Stirling number (GSN) pairs investigated earlier by the author. Also expounded in some detail are two kinds of extended GSN pairs with applications (illustrative examples). 相似文献
100.
Calcium carbonate crystallization process, especially the prenucleation stage, has increasingly been the subject of several works. In the present work, a simple method based on electrical conductivity modeling applied to the FCP (Fast Controlled Precipitation) method data is used to highlight the role of CaCO3o ion pairs on calcium carbonate prenucleation stage. A good agreement was obtained between the resistivity vs pH curves estimated by the McCleskey model equation and obtained experimentally in a FCP test. Results showed that the nucleation process begins with the formation of CaCO3o ion pairs as pre‐nuclei as soon as the calcite‐equilibrium pH is reached. Additionally CaCO3o content increases with pH to form aggregates, which depend on the saturation state of the solution. Basing on our thermodynamic data, these aggregates do not form amorphous calcium carbonate ACC as an intermediate phase. They lead to the formation of stable calcium carbonate nuclei which will further evolve to crystallize. Furthermore we demonstrate that in addition to their inhibitory effect on the Ca2+ and CO32− association to form ion pairs, the two scale inhibitors sodium triphosphate (STP) and sodium polyacrylate (RPI) reduce ion pairs aggregation rate. 相似文献