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1.
JOSEF MÁLEK JINDŘICH NEČAS K. R. RAJAGOPAL 《Archive for Rational Mechanics and Analysis》2002,165(3):243-269
To describe the flows of fluids over a wide range of pressures, it is necessary to take into account the fact that the viscosity
of the fluid depends on the pressure. That the viscosity depends on the pressure has been verified by numerous careful experiments.
While the existence of solutions local-in-time to the equations governing the flows of such fluids are available for small,
special data and rather unrealistic dependence of the viscosity on the pressure, no global existence results are in place.
Our interest here is to establish the existence of weak solutions for spatially periodic three-dimensional flows that are
global in time, for a large class of physically meaningful viscosity-pressure relationships.
(Accepted May 1, 2002) Published online November 15, 2002
Communicated by S. S. ANTMAN 相似文献
2.
C. Bittencourt A. Felten J.-F. Colomer W. Drube J.-J. Pireaux 《Surface science》2007,601(13):2800-2804
Multi-wall carbon nanotubes (MWCNTs) were decorated with metal clusters by thermal evaporation. Transmission electron microscopy (TEM) shows that the nature and extent of metal coverage can be varied by plasma treating the MWCNT surface. The metal clusters on oxygen plasma treated arc-discharge MWCNTs have a more dense distribution than the clusters evaporated on as-synthesized arc-discharge MWCNTs. In contrast, the plasma treatment did not affect the cluster distribution on CVD MWCNTs. Analyses of the valence band and the core levels by X-ray photoelectron spectroscopy suggest poor charge transfer between gold clusters and MWCNTs; on the contrary suggest good charge transfer between Ni clusters and MWCNTs. 相似文献
3.
Detection of Fragment Genesis in the Mass Spectrometer. III. Analysis of Amino-Acid Sequence in Oligopeptides and in Mixtures of Oligopeptides by DADI-Mass Spectrometry. The amino acid sequence was analysed by DADI mass spectrometry in simple oligopeptides and in mixtures containing two or three peptides. 相似文献
4.
We investigate inequalities for derivatives of trigonometric and algebraic polynomials in weighted L P spaces with weights satisfying the Muckenhoupt A p condition. The proofs are based on an identity of Balázs and Kilgore [1] for derivatives of trigonometric polynomials. Also an inequality of Brudnyi in terms of rth order moduli of continuity ωr will be given. We are able to give values to the constants in the inequalities. 相似文献
5.
A waveguide in integrated optics is defined by its refractiveindex. The guide is assumed to be invariant in the propagationdirection while in the transverse direction it is supposed tobe a compact perturbation of an unbounded stratified medium.We are interested in the modes guided by this device, whichare waves with a transverse energy confined in a neighbourhoodof the perturbation. Our goal is to analyse the existence of such guided modes. Underthe assumptions of weak guidance the problem reduces to a two-dimensionaleigenvalue problem for a scalar field. The associated operatoris unbounded, selfadjoint, and bounded from below. Its spectrumconsists of the discrete spectrum corresponding to the guidedmodes and of the essential spectrum corresponding to the radiationmodes. We present existence results of guided modes and an asymptoticstudy at high frequencies, which shows that contrarily to thecase of optical fibers, the number of guided modes can remainbounded. The major tools are the min-max principle and comparisonof results between different eigenvalue problems. The originalityof the present study lies in the stratified character of theunbounded reference medium. 相似文献
6.
C.D. Lytle P.G. Carney R.P. Felten H.F. Bushar R.C. Straight 《Photochemistry and photobiology》1989,50(3):367-371
Dyes which photosensitize membranes may be clinically useful for photodynamic treatment (PDT) of Herpes simplex virus (HSV) infections. It is important to determine whether the enveloped HSV can be inactivated via membrane damage without affecting the genetic material. Selection of appropriate PDT conditions, including the choice of dye, could minimize viral mutagenesis. We determined the mutagenesis caused by PDT employing three membrane-photosensitizing dyes of potential use in cancer photochemotherapy (Photofrin II, polyhematoporphyrin esters, zinc phthalocyanine tetrasulfonates) and a DNA-photosensitizing dye (proflavine sulfate). The effects were compared to those caused by exposure of HSV to ultraviolet radiation (UV). The procedure consisted of incubating HSV with microgram/ml (microM) concentrations of the dye, irradiating the samples with broad spectrum visible/near-UV radiation (Daylight fluorescent lamps) and assaying the survival of the treated HSV. Zinc phthalocyanine was the most potent dye per absorbed photon for inactivating HSV. In parallel with determination of survival, progeny of the surviving virus were grown for determination of mutagenesis. The progeny virus was harvested and subsequently assayed in the presence and absence of 40 micrograms/ml iododeoxycytidine (ICrd) to determine the frequency of mutation to ICrd resistance. Mutation frequencies were determined for progeny from the 1-4% survival level. For PDT with each membrane-photosensitizing dye, only zinc phthalocyanine increased the mutation frequency over the untreated control. This increase was less than 2-fold. Proflavine increased the mutation frequency 2-3 fold over the untreated control. Ultraviolet produced a 15-20 fold increase over the untreated control.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
7.
Jay Jin Saranya Kittanakom Victoria Wong Beverly AS Reyes Elisabeth J Van Bockstaele Igor Stagljar Wade Berrettini Robert Levenson 《BMC neuroscience》2010,11(1):33
Background
Opioid agonist drugs produce analgesia. However, long-term exposure to opioid agonists may lead to opioid dependence. The analgesic and addictive properties of opioid agonist drugs are mediated primarily via the mu-opioid receptor (MOR). Opioid agonists appear to alter neuronal morphology in key brain regions implicated in the development of opioid dependence. However, the precise role of the MOR in the development of these neuronal alterations remains elusive. We hypothesize that identifying and characterizing novel MOR interacting proteins (MORIPs) may help to elucidate the underlying mechanisms involved in the development of opioid dependence. 相似文献8.
M. Felten 《Acta Mathematica Hungarica》2008,118(3):265-297
The paper is concerned with bounds for integrals of the type
, involving Jacobi polynomials p
n
(α,β)
and Jacobi weights w
(a,b)
depending on α,β, a, b > −1, where the subsets U
k
(x) ⊂ [−1, 1] located around x and are given by with . The functions to be integrated will also be of the type on the domain [−1,1] t/ U
k
(x). This approach uses estimates of Jacobi polynomials modified Jacobi weights initiated by Totik and Lubinsky in [1]. Various
bounds for integrals involving Jacobi weights will be derived. The results of the present paper form the basis of the proof
of the uniform boundedness of (C, 1) means of Jacobi expansions in weighted sup norms in [3].
相似文献
9.
N-Aminodipeptide derivatives can be easily prepared with high optical purity on solid phase via a Mitsunobu protocol between a solid supported α-hydroxyacid and a free phthaloylated α-Z-N-aminohydrazide. 相似文献
10.
We present an approach for the accumulation and filtering of nano- and microparticles in microfluidic devices that is based on the generation of electric traveling waves in the radio-frequency range. Upon application of the electric field via a microelectrode array, complex particle trajectories and particle accumulation are observed in well-defined regions in a microchannel. Through the quantitative mapping of the 3-D flow pattern using two-focus fluorescence cross-correlation spectroscopy, two vortices could be identified as one of the sources of the force field that induces the formation of particle clouds. Dielectrophoretic forces that directly act on the particles are the second source of the force field. A thorough 2-D finite element analysis identifies the electric traveling wave mechanism as the cause for the unexpected flow behavior observed. Based on these findings, strategies are discussed, first, for avoiding the vortices to optimize electrohydrodynamic micropumps and, secondly, for utilizing the vortices in the development of microdevices for efficient particle accumulation, separation, and filtering. Such devices may find numerous biomedical applications when highly diluted nano- and microsuspensions have to be processed. 相似文献