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81.
研究给出了非齐次树上m重非齐次马氏链的一类强偏差定理. 相似文献
82.
许兴业 《高校应用数学学报(A辑)》2017,32(4)
研究一类奇异非线性多重调和方程?~mu=f(|x|,u,|▽u|)u~(-β),给出了方程存在正的径向对称整体解的充分必要条件和解的性质. 相似文献
83.
刘臻 《数学年刊A辑(中文版)》2017,38(2):201-214
研究了完全耦合正倒向随机控制系统的最优控制问题.得到了粘性解框架下的,控制变量同时出现在正倒向随机系统的漂移项和扩散项中的最优控制问题的验证定理.还讨论了验证定理在构造随机最优反馈控制中的应用. 相似文献
84.
This note is denoted to establishing sharp distortion theorems for subclasses of α-Bloch mappings defined in the unit ball of Cn with critical points.Furthermore,the estimates of Bloch constant with respect to these subclasses are given. 相似文献
85.
86.
More than 60% commonly used pharmaceutical active ingredients are chiral compounds. Developing more effective and safe chiral compounds has become a focus in the pharmaceutical industry. Chiral compounds widely exist in traditional Chinese medicine and include alkaloids, flavonoids, volatile oils, and amino acids. The characterization of chiral compounds used in traditional Chinese medicine remains limited. Here, the characterization of chiral compounds commonly used in traditional Chinese medicine is reviewed focusing upon their separation and pharmacology. 相似文献
87.
88.
89.
《Journal of separation science》2017,40(8):1796-1804
The quality consistency of Yinqiaojiedu tablets (YQJDTs) was monitored by extracting their electrophoretic fingerprint and marker compound data that were obtained using capillary electrophoresis. To select the suitable background electrolyte, wing‐shape method was proposed. A background electrolyte composed of 103.1 mM boric acid, 51.6 mM sodium borate, 9.8 mM disodium hydrogen phosphate, and 15.6 mM sodium dihydrogen phosphate was used to separate compounds. Under the optimized conditions, the content of three marker compounds was determined in 25 YQJDT samples. The capillary electrophoresis fingerprints were developed simultaneously, then 25 samples from two manufacturers were clearly divided into two clusters based on the principal component analysis. In fingerprint assessments, systematic quantified fingerprint method was adopted for integrative quality discrimination of YQJDTs from both qualitative and quantitative perspectives, by which the qualities of 25 samples were well differentiated. In addition, partial least squares model was established to explore fingerprint–efficacy relationship between the fingerprints and the antioxidant activities in vitro, providing clinically useful information for quality control. The proposed method was reliable and comprehensive, which could be used for a valuable reference to monitor the quality consistency of traditional Chinese medicines. 相似文献
90.
《Journal of separation science》2017,40(14):2933-2940
The extraction adsorbent was fabricated by immobilizing the highly specific recognition and binding of aptamer onto the surface of Fe3O4 magnetic nanoparticles, which not only acted as recognition elements to recognize and capture the target molecule berberine from the extract of Cortex phellodendri , but also could favor the rapid separation and purification of the bound berberine by using an external magnet. The developed solid‐phase extraction method in this work was useful for the selective extraction and determination of berberine in Cortex phellodendri extracts. Various conditions such as the amount of aptamer‐functionalized Fe3O4 magnetic nanoparticles, extraction time, temperature, pH value, Mg2+ concentration, elution time and solvent were optimized for the solid‐phase extraction of berberine. Under optimal conditions, the purity of berberine extracted from Cortex phellodendri was as high as 98.7% compared with that of 4.85% in the extract, indicating that aptamer‐functionalized Fe3O4 magnetic nanoparticles‐based solid‐phase extraction method was very effective for berberine enrichment and separation from a complex herb extract. The applicability and reliability of the developed solid‐phase extraction method were demonstrated by separating berberine from nine different concentrations of one Cortex phellodendri extract. The relative recoveries of the spiked solutions of all the samples were between 95.4 and 111.3%, with relative standard deviations ranging between 0.57 and 1.85%. 相似文献