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521.
Erwin Schörner 《Geometriae Dedicata》2000,80(1-3):157-171
We endow the set of all formal power series with coefficients in a ternary field and exponents in a totally ordered loop with a ternary field operation such that a uniform valuation is given by the natural ultrametric distance. Any ordering of the coefficient ternary field can be extended to an ordering of the Hahn ternary field which is compatible with the given valuation. 相似文献
522.
为实现简单基质样品中常规阴离子的快速分析,选用Dionex IonPac AS22-fast(4mm×150mm)离子交换色谱柱,通过优化流速、淋洗液浓度等色谱条件,使F-、Cl-、NO3-、NO2-、Br-、PO43-、SO42-7种常规阴离子在3.5min内分离完全,实现简单基质样品中常规阴离子的快速测定。 相似文献
523.
完备凸度量空间中(次)相容和集值广义非扩张映象的公共不动点定理 总被引:5,自引:0,他引:5
本文在完备凸度量空间中,利用集值和单值映象(次)相容的一些条件,建立了数值广义非扩张映象存在公共不动点的一个充要条件和一个充分条件.我们的结果改进、扩充和发展了文[2~7]中的主要结果. 相似文献
524.
Robert Hancock Daniel Král' Matjaž Krnc Jan Volec 《Random Structures and Algorithms》2023,62(1):181-218
A graph is common if the number of monochromatic copies of in a 2-edge-coloring of the complete graph is asymptotically minimized by the random coloring. The classification of common graphs is one of the most intriguing problems in extremal graph theory. We study the notion of weakly locally common graphs considered by Csóka, Hubai, and Lovász [arXiv:1912.02926], where the graph is required to be the minimizer with respect to perturbations of the random 2-edge-coloring. We give a complete analysis of the 12 initial terms in the Taylor series determining the number of monochromatic copies of in such perturbations and classify graphs based on this analysis into three categories:
- Graphs of Class I are weakly locally common.
- Graphs of Class II are not weakly locally common.
- Graphs of Class III cannot be determined to be weakly locally common or not based on the initial 12 terms.
525.
Yumin Cao Ning Zhou Tong Liu Jinying Zhang Yongxiang Wang Bingxian Zhang Zhenkai Zhang Weisheng Feng Xiaoke Zheng 《Journal of separation science》2023,46(9):2200895
Ephedra herba is a conventional Chinese medicine to treat cold, fever, asthma, edema, and lung diseases in the clinic. At present, most pharmacokinetic studies focus on the pharmacokinetic process of alkaloids in normal animals. However, the non-alkaloid components are also active. In addition, the pharmacokinetic studies under pathological state make more sense for clarifying the material basis of efficacy. In this study, a sensitive and rapid ultra-high-performance–tandem mass spectrometry method was developed and applied to determine nine bioactive components (ephedrine, pseudoephedrine, methylephedrine, (+)-catechin, epicatechin, vitexin, vicenin-2, cinnamic acid, and ferulic acid) in normal, common cold and nephrotic syndrome rats after the oral administration of Ephedra herba. Compared to the normal group, except for ferulic acid, the exposure levels of the other eight components were significantly increased and the plasma clearance clearly declined in common cold rats. Similarly, the exposure levels of seven components other than cinnamic acid and ferulic acid were also significantly augmented and the plasma clearance decreased significantly in nephrotic syndrome rats. In brief, the pathological conditions of the common cold and nephrotic syndrome could lead to alterations in the pharmacokinetics profiles of the nine components, which provide a reference for further exploration of the pharmacodynamics basis of Ephedra herba. 相似文献
526.