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181.
Duree de vie et depolarisation par collisions avec l''helium des niveaux 5P3/2 Et 5P1/2 de l''ion Cd
J. Hamel 《Optics Communications》1974,10(4):331-336
The lifetimes of the Cd+ 52P3/2 and 52P1/2 states have been measured by the Hanle effect. The Cd+ ions are produced in a d.c. discharge in cadmium vapor, with helium as buffer gas. The results are: τ(52P3/2) = (2.60±0.20) ×10−9sec, and τ(52P1/2) = (3.05 ± 0.13) × 10−9sec.
We measured also the cross sections for the destruction of the orientation in the 52P1/2Cd+ state (<5Å2), of the orientation (18±10Å2) and of the alignment (46±10Å2) in the 52P3/2 state due to collisions with the helium atoms. 相似文献
182.
This study compares microfluidic technology (Protein 200 LabChip Assay kit, Agilent 2100 Bioanalyzer, referred to here as Protein 200) to the traditional approach for protein analysis, one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), for the sizing and quantification of immunoglobulin G (IgG) in hybridoma cell cultures. Internal references differ between each method: purified IgG was used alone in SDS-PAGE while myosin (the upper marker) was added to each sample in Protein 200. The IgG used here were produced in cultures propagated in either a serum-free or a serum-containing medium. With serum-containing samples, there was a significant difference in the IgG concentrations (p < 0.05) between SDS-PAGE and Protein 200. The concentration determined by SDS-PAGE was significantly higher (> 30%) than by Protein 200 or by high-pressure liquid chromatography (HPLC) because the large amounts of serum albumin in the samples affect the accuracy of SDS-PAGE. Protein 200 can determine size similarly to SDS-PAGE in serum-free samples (standard error of the mean, SEM, < 1%, 95% confidence < +/-1%), unlike in serum-containing samples. The Protein 200 assay was more effective than the traditional one-dimensional SDS-PAGE in determining concentration and size of IgG in cell culture samples and it provided a miniaturized and convenient platform for rapid analysis. 相似文献
183.
Mao PC Mouscadet JF Leh H Auclair C Hsu LY 《Chemical & pharmaceutical bulletin》2002,50(12):1634-1637
A systematic series of chemically modified coumarin dimmers has been synthesized and tested for their inhibitory activity against HIV-1 integrase. We observed that modified coumarin dimmers containing hydrophobic moiety on the linker display potent inhibitory activities. 相似文献
184.
Advances are needed in random-display technologies to more tightly link drug actions and functions to the genes that control physiological processes. The reports discussed here explore two sides of these issues-generating new library formats and identifying the targets of drug ligands. 相似文献
185.
Study of a system for the isothermal separation of components in a binary alloy with change of phase
Kessler Daniel; Scheid Jean-Francois; Schimperna Giulio; Stefanelli Ulisse 《IMA Journal of Applied Mathematics》2004,69(3):233-257
An isothermal model describing the separation of the componentsof a binary metallic alloy is considered. A process of phasetransition is also assumed to occur in the solder; hence, thestate of the material is described by two order parameters,i.e. the concentration c of the first component and the phasefield . A physical derivation is provided starting from energybalance considerations. The resulting system of PDEs consistsof a rather regular second-order parabolic equation for coupledwith a fourth-order relation of CahnHilliard type forc with constraint and solution-dependent mobility. Global existenceof solutions is proved and several regularity properties arediscussed under more restrictive assumptions on the physicalparameters. Continuous dependence on data is shown in a specialcase. An asymptotic analysis of the model is also performed,yielding at the limit step a coupling of the original phasefield equation with a Stefan-like system for c. 相似文献
186.
Banwell MG Edwards AJ Jolliffe KA Smith JA Hamel E Verdier-Pinard P 《Organic & biomolecular chemistry》2003,1(2):296-305
The title alkaloid 1 and its B-nor-congener 3, both of which display potent and unusual anti-mitotic properties, have been synthesized in racemic form and characterised by single-crystal X-ray analysis. 相似文献
187.
188.
We consider repeated two-person zero-sum games in which each player has only partial information about a chance move that takes place at the beginning of the game. Under some conditions on the information pattern it is proved that \(\mathop {\lim }\limits_{n \to \infty } v_n\) exists,v n being the value of the game withn repetitions. Two functional equations are given for which \(\mathop {\lim }\limits_{n \to \infty } v_n\) is the only simultaneous solutions. We also find the least upper bound for the error term \(\left| {v_n - \mathop {\lim }\limits_{n \to \infty } v_n } \right|\) . 相似文献
189.
We prove that, in a two‐dimensional strip, a steady flow of an ideal incompressible fluid with no stationary point and tangential boundary conditions is a shear flow. The same conclusion holds for a bounded steady flow in a half‐plane. The proofs are based on the study of the geometric properties of the streamlines of the flow and on one‐dimensional symmetry results for solutions of some semilinear elliptic equations. Some related rigidity results of independent interest are also shown in n‐dimensional slabs in any dimension n.© 2016 Wiley Periodicals, Inc. 相似文献
190.
This paper is devoted to time-global solutions of the Fisher-KPP equation in ℝ
N
:
where f is a C
2 concave function on [0,1] such that f(0)=f(1)=0 and f>0 on (0,1). It is well known that this equation admits a finite-dimensional manifold of planar travelling-fronts solutions.
By considering the mixing of any density of travelling fronts, we prove the existence of an infinite-dimensional manifold
of solutions. In particular, there are infinite-dimensional manifolds of (nonplanar) travelling fronts and radial solutions.
Furthermore, up to an additional assumption, a given solution u can be represented in terms of such a mixing of travelling fronts.
Accepted October 30, 2000?Published online March 21, 2001 相似文献