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Gero Kleinert 《Zeitschrift für Physik A Hadrons and Nuclei》1970,236(3):250-259
The scintillation light yield of anthracene single crystals excited by 8.78 MeV α-particles and its dependence on particle impact direction is investigated. Special attention is paid to a local maximum of the scintillation light yield first observed by Kienzle. The local maximum is found to occur exactly in the (a, b)-plane. This is confirmed in the temperature range from 14 to 90 °K. According to a theory by Bönsch this local maximum is explained by anisotropic diffusion of triplet excitons. In the interpretation of the local maximum channeling effects should be excluded. 相似文献
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Gero Friesecke Richard D. James Stefan Müller 《Archive for Rational Mechanics and Analysis》2006,180(2):183-236
We derive a hierarchy of plate models from three-dimensional nonlinear elasticity by Γ-convergence. What distinguishes the
different limit models is the scaling of the elastic energy per unit volume ∼hβ, where h is the thickness of the plate. This is in turn related to the strength of the applied force ∼hα. Membrane theory, derived earlier by Le Dret and Raoult, corresponds to α=β=0, nonlinear bending theory to α=β=2, von Kármán theory to α=3, β=4 and linearized vK theory to α>3. Intermediate values of α lead to certain theories with constraints. A key ingredient in the proof is a generalization to higher derivatives of our
rigidity result [29] which states that for maps v:(0,1)3→ℝ3, the L2 distance of ∇v from a single rotation is bounded by a multiple of the L2 distance from the set SO(3) of all rotations. 相似文献
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The energy functional of nonlinear plate theory is a curvature functional for surfaces first proposed on physical grounds by G. Kirchhoff in 1850. We show that it arises as a Γ‐limit of three‐dimensional nonlinear elasticity theory as the thickness of a plate goes to zero. A key ingredient in the proof is a sharp rigidity estimate for maps v : U → ?n, U ? ?n. We show that the L2‐distance of ?v from a single rotation matrix is bounded by a multiple of the L2‐distance from the group SO(n) of all rotations. © 2002 Wiley Periodicals, Inc. 相似文献
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Gero Fendler Karlheinz Gröchenig Michael Leinert 《Integral Equations and Operator Theory》2008,61(4):493-509
We study infinite matrices A indexed by a discrete group G that are dominated by a convolution operator in the sense that for x ∈ G and some . This class of “convolution-dominated” matrices forms a Banach-*-algebra contained in the algebra of bounded operators on
ℓ
2(G). Our main result shows that the inverse of a convolution-dominated matrix is again convolution-dominated, provided that
G is amenable and rigidly symmetric. For abelian groups this result goes back to Gohberg, Baskakov, and others, for non-abelian
groups completely different techniques are required, such as generalized L
1-algebras and the symmetry of group algebras.
K. G. was supported by the Marie-Curie Excellence Grant MEXT-CT 2004-517154. 相似文献
60.
Hooff GP Meesters RJ van Kampen JJ van Huizen NA Koch B Al Hadithy AF van Gelder T Osterhaus AD Gruters RA Luider TM 《Analytical and bioanalytical chemistry》2011,400(10):3473-3479
The neuraminidase inhibitor oseltamivir (Tamiflu®) is currently the first-line therapy for patients with influenza virus infection. Common analysis of the prodrug and its active metabolite oseltamivircarboxylate is determined via extraction from plasma. Compared with these assays, dried blood spot (DBS) analysis provides several advantages, including a minimum sample volume required for the measurement of drugs in whole blood. Samples can easily be obtained via a simple, non-invasive finger or heel prick. Mainly, these characteristics make DBS an ideal tool for pediatrics and to measure multiple time points such as those needed in therapeutic drug monitoring or pharmacokinetic studies. Additionally, DBS sample preparation, stability, and storage are usually most convenient. In the present work, we developed and fully validated a DBS assay for the simultaneous determination of oseltamivir and oseltamivircarboxylate concentrations in human whole blood. We demonstrate the simplicity of DBS sample preparation, and a fast, accurate and reproducible analysis using ultra high-performance liquid chromatography coupled to a triple quadrupole mass spectrometer. A thorough validation on the basis of the most recent FDA guidelines for bioanalytical method validation showed that the method is selective, precise, and accurate (≤15% RSD), and sensitive over the relevant clinical range of 5–1,500 ng/mL for oseltamivir and 20–1,500 ng/mL for the oseltamivircarboxylate metabolite. As a proof of concept, oseltamivir and oseltamivircarboxylate levels were determined in DBS obtained from healthy volunteers who received a single oral dose of Tamiflu®. 相似文献