2,115 research outputs found
Mixed principal eigenvalues in dimension one
This is one of a series of papers exploring the stability speed of
one-dimensional stochastic processes. The present paper emphasizes on the
principal eigenvalues of elliptic operators.
The eigenvalue is just the best constant in the -Poincar\'e inequality
and describes the decay rate of the corresponding diffusion process. We present
some variational formulas for the mixed principal eigenvalues of the operators.
As applications of these formulas, we obtain case by case explicit estimates, a
criterion for positivity, and an approximating procedure for the eigenvalue.Comment: 45 pages; Front. Math. China, 201
Macroscopical Entangled Coherent State Generator in V configuration atom system
In this paper, we propose a scheme to produce pure and macroscopical
entangled coherent state. When a three-level ''V'' configuration atom interacts
with a doubly reasonant cavity, under the strong classical driven condition,
entangled coherent state can be generated from vacuum fields. An analytical
solution for this system under the presence of cavity losses is also given
Determination of cyclovirobuxine D in human plasma by liquid chromatography tandem mass spectrometry and application in a pharmacokinetic study
AbstractA sensitive and reliable method based on liquid chromatography tandem mass spectrometry (LC–MS/MS) for the quantitation of cyclovirobuxine D in human plasma has been developed and validated. Sample preparation by solid phase extraction was followed by separation on a CN column with a mobile phase of methanol–water (95:5, v/v) containing 0.2% formic acid. Mass spectrometric detection in the positive ion mode was carried out by selected reaction monitoring (SRM) of the transitions at m/z 403.0→372.0 for cyclovirobuxine D and m/z 325.0→234.0 for citalopram (internal standard). The method was linear in the range 10–200ng/L with LLOQ of 10ng/L, recovery >85%, and no significant matrix effects. Intra- and inter-day precisions were all <9% with accuracies of 94.0–104.8%. The method was successfully applied to a pharmacokinetic study involving a single oral administration of a 2mg cyclovirobuxine D tablet to twenty-two healthy Chinese volunteers
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