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41.
Monatshefte für Mathematik - 相似文献
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Theodor Molien 《Mathematische Annalen》1893,42(2):308-312
Ohne Zusammenfassung 相似文献
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We theoretically study the coupling of Bose-Einstein condensed atoms to the mechanical oscillations of a nanoscale cantilever with a magnetic tip. This is an experimentally viable hybrid quantum system which allows one to explore the interface of quantum optics and condensed matter physics. We propose an experiment where easily detectable atomic spin flips are induced by the cantilever motion. This can be used to probe thermal oscillations of the cantilever with the atoms. At low cantilever temperatures, as realized in recent experiments, the backaction of the atoms onto the cantilever is significant and the system represents a mechanical analog of cavity quantum electrodynamics. With high but realistic cantilever quality factors, the strong coupling regime can be reached, either with single atoms or collectively with Bose-Einstein condensates. We discuss an implementation on an atom chip. 相似文献
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In the present study, a rapid and sensitive LC-ESI-MS/MS method for quantification of (S)-fluoxetine as a native marker in mass spectrometry (MS) binding assays addressing the human serotonin transporter (hSERT)
was developed and validated. The concept of MS binding assays based on mass spectrometric quantification of a nonlabeled marker
recently introduced by us represents a promising alternative to conventional radioligand binding without the drawbacks inherently
connected with radioisotope labeling. For high-performance liquid chromatography (HPLC), a 20 × 2-mm RP-18 column with a mobile
phase composed of acetonitrile and ammonium bicarbonate buffer (5 mmol L−1, pH 9.5) at a ratio of 80:20 (v/v) and a flow rate of 800 μL min−1 in an isocratic mode were used, resulting in a chromatographic cycle time of 60 s. Employing [2H5]fluoxetine as internal standard enabled ESI-MS/MS quantification of (S)-fluoxetine between 3 nmol L−1 and 50 pmol L−1 (LLOQ) in matrix obtained from binding experiments without the need of any sample preparation. Validation of the method showed
that linearity, intra-, and inter-batch accuracy as well as precision meet the requirements of the FDA guidance for bioanalytical
method validation. Considering sensitivity and speed, the established method is clearly superior to those published for biological
matrices so far. Furthermore, the method was transferred to other RP-18 columns of different lengths and respective validation
experiments demonstrated its versatility and chromatographic robustness. Finally, the newly developed method was successfully
applied to MS binding assays for hSERT. The affinity determined for (S)-fluoxetine in saturation experiments was in good agreement with literature data obtained in respective radioligand binding
assays. 相似文献
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Nickel hydrides supported by a terphenyl diphosphine were synthesized and found to undergo nickel-to-arene H-transfers. Some of the resulting complexes also undergo the reverse (C-to-Ni) H-migration, indicating the potential for storing H-equivalents in this type of pincer ligand. NMR spectroscopy, single crystal X-ray diffraction, and isotopic labeling studies investigating the mechanism of these processes are discussed. 相似文献
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Filipe J. Marques M. Theodor Loots Andriëtte Bekker 《Mathematical Methods in the Applied Sciences》2019,42(17):5718-5735
Series representations for several density functions are obtained as mixtures of generalized gamma distributions with discrete mass probability weights, by using the exponential expansion and the binomial theorem. Based on these results, approximations based on mixtures of generalized gamma distributions are proposed to approximate the distribution of the sum of independent random variables, which may not be identically distributed. The applicability of the proposed approximations are illustrated for the sum of independent Rayleigh random variables, the sum of independent gamma random variables, and the sum of independent Weibull random variables. Numerical studies are presented to assess the precision of these approximations. 相似文献
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