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131.
Shari Wu Wenkui Li Tapan Mujamdar Tom Smith Matthew Bryant Francis L. S. Tse 《Biomedical chromatography : BMC》2010,24(6):632-638
A high‐throughput LC–MS/MS bioanalytical method was developed and validated for the determination of hydrocortisone in mouse serum via supported liquid extraction (SLE) in a 96‐well plate format. Although sample extracts from SLE result in similar matrix effects compared with conventional liquid–liquid extraction (LLE), greater analyte extraction recovery and much higher analysis throughput for the quantitative analysis of hydrocortisone in mouse serum were obtained. The current LC‐MS/MS method was validated for a concentration range of 2.00–2000 ng/mL for hydrocortisone using a 0.100 mL volume of mouse serum. The intra‐ and inter‐day precision and accuracy of the quality control samples at low, medium and high concentration levels showed ≤12.9% CV and ?3.4–6.2% bias for the analyte in mouse serum. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
132.
W. G. Campbell J. C. Mc Gowan St. A. Bryant A. J. Bailey A. Orup R. I. Thieme H. Bergström K. G. Trobeck P. W. Moryganow J. I. Wlassjuk N. K. Koshewnikowa G. S. Ssurta G. Jayme H. Pfretzschner R. Steinmann M. G. van Beckum G. J. Ritter J. H. Barbour C. F. Cross E. J. Bevan 《Analytical and bioanalytical chemistry》1940,119(1-2):67-71
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134.
Transport in Porous Media - The possibility of broaching, or the release of fluids at the seafloor due to a damaged or faulty well, is a hazard that must be assessed in the well permitting process.... 相似文献
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136.
It is shown that if K is any regular complete multipartite graph of even degree, and F is any bipartite 2‐factor of K, then there exists a factorization of K into F; except that there is no factorization of K6, 6 into F when F is the union of two disjoint 6‐cycles. 相似文献
137.
An algorithm for producing identities which hold in any given finite quasigroup is described. Identities produced by the algorithm are used to prove several results concerning varieties of quasigroups. In particular varieties of quasigroups associated with various combinatorial designs are examined. 相似文献
138.
We describe an experiment, in situ temperature jump dynamic nuclear polarization (TJ-DNP), that is demonstrated to enhance sensitivity in liquid-state NMR experiments of low-gamma spins--13C, 15N, etc. The approach consists of polarizing a sample at low temperature using high-frequency (140 GHz) microwaves and a biradical polarizing agent and then melting it rapidly with a pulse of 10.6 microm infrared radiation, followed by observation of the NMR signal in the presence of decoupling. In the absence of polarization losses due to relaxation, the enhancement should be epsilon+ = epsilon(T(obs)/T(mu)(wave)), where epsilon+ is the observed enhancement, epsilon is the enhancement obtained at the temperature where the polarization process occurs, and T(mu)(wave) and T(obs) are the polarization and observation temperatures, respectively. In a single experimental cycle, we observe room-temperature enhancements, epsilon(dagger), of 13C signals in the range 120-400 when using a 140 GHz gyrotron microwave source, T(mu)(wave) = 90 K, and T(obs) = 300 K. In addition, we demonstrate that the experiment can be recycled to perform signal averaging that is customary in contemporary NMR spectroscopy. Presently, the experiment is applicable to samples that can be repeatedly frozen and thawed. TJ-DNP could also serve as the initial polarization step in experiments designed for rapid acquisition of multidimensional spectra. 相似文献
139.
The Decomposition of Lie Powers 总被引:1,自引:0,他引:1
Let G be a group, F a field of prime characteristic p and Va finite-dimensional FG-module. Let L(V) denote the free Liealgebra on V regarded as an FG-submodule of the free associativealgebra (or tensor algebra) T(V). For each positive integerr, let Lr (V) and Tr (V) be the rth homogeneous components ofL(V) and T(V), respectively. Here Lr (V) is called the rth Liepower of V. Our main result is that there are submodules B1,B2, ... of L(V) such that, for all r, Br is a direct summandof Tr(V) and, whenever m 0 and k is not divisible by p, themodule is the direct sum of , . Thus every Lie power is a direct sum of Lie powers of p-powerdegree. The approach builds on an analysis of Tr (V) as a bimodulefor G and the Solomon descent algebra. 2000 Mathematics SubjectClassification 17B01 (primary), 20C07, 20C20 (secondary). 相似文献
140.
We show via an exhaustive computer search that there does not exist a (K6?e)‐decomposition of K29. This is the first example of a non‐complete graph G for which a G‐decomposition of K2|E(G)|+1 does not exist. © 2009 Wiley Periodicals, Inc. J Combin Designs 18: 94–104, 2010 相似文献