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J. Giroire T. Ha‐Duong V. Moumas 《Mathematical Methods in the Applied Sciences》2005,28(13):1527-1552
This article deals with a boundary value problem for Laplace equation with a non‐linear and non‐local boundary condition. This problem comes from petroleum engineering and is used to obtain an estimation of well productivity. The non‐linear and non‐local boundary condition is written on the well boundary. On the outer reservoir boundaries, we have both Dirichlet and Neumann conditions. In this paper, we prove the existence and uniqueness of a solution to this problem. The existence is proved by Schauder theorem and the uniqueness is obtained under more restricted conditions, when the involved operator is a contraction. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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The univariate generalized beta- and generalized F-distributions are frequently in recent statistical modellings and applications. They have richer properties than the standard beta- and Snedecor F-distributions and provide more flexibility than these distributions, of which they are natural extensions. Their connection with the Gauss hypergeometric function and Lauricella functions leads to further generalizations and important properties. This article gives a unified and up-to-date treatment of these two generalized distributions using only simple arguments. Proofs are given for some original results and a complete reference to their source is provided for established ones. The important problem of parameter estimation is also studied. 相似文献
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We consider the first initial boundary-value problem for strongly parabolic systems in an infinite cylinder with nonsmooth boundary. We establish conditions for the existence of generalized solutions, an estimate for this solutions, and an estimate for the derivative of the solution. 相似文献
6.
采用浮床黑麦草(Lolium multi florum)对畜禽养殖富营养水体氨氮的净化效应及动态过程进行了研究.结果表明:浮床黑麦草对富营养水体中的氨氮具有明显的净化效果.当覆盖率30%时,对氨氮的去除率最高可达到95.89%.对其去除水体氨氮的动态过程拟合表明符合三次方程曲线.该研究为冬季陆生植物修复富营养水体提供重要依据. 相似文献
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We report a new approach for the self-assembly of cuboid micro-parts onto Si substrates to construct three-dimensional microstructures. To perform assembly, the Si substrates are prepared with a deep cavity array as binding sites. An aggregate composed of hundreds of uniformly aligned micro-parts is formed at the C10F18-H2O interface. The micro-parts are arranged by passing the substrate through the aggregate of micro-parts, thus the micro-parts are left on the substrate, and then the substrate is vibrated ultrasonically in the solution, making it possible for the micro-parts to fall into the cavities on the substrate. Finally the substrate is pulled out of the solution after assembly. This technique could give a high yield of up to 70%, providing a new method for micro-assembly. 相似文献
8.
Effect of Molecular Weight on Liquid Crystal Photoalignment by Photosensitive Polyester Containing Thrifluoromethyl Moieties 下载免费PDF全文
We investigate the liquid-crystal (LC) alignment direction on photoalignment films formed from photosensitive polyester containing thrifluoromethyl moieties (PPDA) with various molecular weights by crossed polarized optical microscopy. It is found that LC alignment behaviour changes with molecular weight of PPDA. The LC alignment on PPDA irradiated films with the highest molecular weight is homogeneous, while those with low and intermediate molecular weights are homeotropic. However, surface morphologies show weak dependence on molecular weight. The surfaces are smooth and there is no clear morphological anisotropy on these aligned films observed by an atomic force microscope. The surface energies of the irradiated films are also measured by using an indirect contact-angle method where both surface energy and its polar component, increase with increasing molecular weight. Different polar surface energies can be considered as a main reason for different alignment characteristics. 相似文献
9.
W. Borchers R. Neugart E. W. Otten H. T. Duong G. Ulm K. Wendt ISOLDE Collaboration 《Hyperfine Interactions》1987,34(1-4):25-29
The hyperfine structure (hfs) and isotope shift (IS) in the isotopic chain of the radioactive element radon have been studied for the first time. The measurements were carried out by collinear fast-beam laser spectroscopy at the mass separator facility ISOLDE at CERN. The IS between 16 isotopes in the mass range 202A222 and the hfs of 7 odd-A isotopes were determined in the transitions 7s [3/2]2-7p [5/2]3 (745 nm) of Rn I. The nuclear spins and moments, as well as the observed inversion of the odd-even staggering for218–222Rn, can be associated with the effects of octupole instability around N=134.This work was supported by the Bundesministerium für Forschung und Technologie and the Deutsche Forschungsgemeinschaft. 相似文献
10.
A "one-step" procedure, that not only removes the color and blocking proteins used in the colorimetric immunodetection step but also stains the proteins originally on the blot, is presented. Following immunostaining and recording of immunoreactive spots, the blot was allowed to air-dry overnight (or longer) at room temperature and then counterstained with a colloidal gold solution. This "air-drying" process apparently altered the affinity of the blocking proteins (and possibly other proteins added subsequently to the blotting step) towards the nitrocellulose membrane causing them to be removed by the acidic colloidal gold solution while the "blotted" proteins were being stained. The sensitivity of this counterstained blot was comparable to that of the blot without going through the immunodetection process. Since both immunodetection and protein staining were carried out on the same blot, this allowed easy identification of many immunoreactive spots to their corresponding proteins when the two profiles were superimposed. Using this procedure, we have detected 25 immunoreactive spots (or allergens) from the whole body extract of the German cockroach (Blattella germanica) that contribute to asthma and assigned them to their corresponding proteins on a two-dimensional (2-D) protein map. The apparent Mr and pI for each of the allergens were determined. We have also located one of the major cockroach allergens, Bla g 5 (glutathione S-transferase). Two-dimensional zymography revealed the presence of ten gelatinase-type proteolytic enzymes. Only one of the ten proteases comigrated with the immunoreactive proteins indicating that unlike other allergen-producing systems, most of the cockroach allergens do not possess protease activity. 相似文献