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In this paper, we consider the continuous-time nonzero-sum stochastic games under the constrained average criteria. The state space is denumerable and the action space of each player is a general Polish space. The transition rates, reward and cost functions are allowed to be unbounded. The main hypotheses in this paper include the standard drift conditions, continuity-compactness condition and some ergodicity assumptions. By applying the vanishing discount method, we obtain the existence of stationary constrained average Nash equilibria. 相似文献
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对二维分离流涡黏性系数非线性分布的新认识 总被引:4,自引:0,他引:4
以弱非线性涡黏性模型为出发点,对Delery分离流动实验结果进行分析并获得了非平衡态分离区涡黏性系数与形状因子J之间的非线性关系. 该非线性关系显示在分离起始阶段,涡黏性系数较平衡态先减小,后增大;再附阶段,涡黏性系数较平衡态数值逐渐增大,并在再附点位置接近最大,而后又逐渐减小,恢复到平衡态水平. 总结涡黏性系数的这种非线性发展数学关系式,并将它应用于BL模型,在不添加微分方程的情况下发展出一种适用于分离流动的改进代数湍流模型. 对低速平板流动,跨声速,超声速以及高超声速分离流动的计算结果表明,该改进湍流模型可以较准确地模拟各类复杂分离流动,计算精度明显优于传统代数模型以及一些两方程模型,而计算工作量仍与BL模型相当. 这表明所提出的涡黏性系数非线性发展规律是正确的,且应用在二维分离流动中具有一定的普适性. 相似文献
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Yitao Li Jian Lin Wenqiang Yao Guoliang Gao Dewang Jing Yang Wu 《Journal of heterocyclic chemistry》2020,57(5):2128-2138
Downy mildew is a very important detrimental disease that lead reduced to fruits and vegetables. Due to the continuous growth of drug resistance, finding novel fungicides with dissimilar modes of function from present fungicides for controlling downy mildew are imminent. This work is an extension of our preceding research on the original triazole sulfonamide derivatives lead compound. Triazole sulfonamide as a remarkable nitrogen-containing heterocyclic compound opposed cucumber downy mildew (CDM) develops a quite vital part in the sphere of the study of new farm chemicals. The existing report designs a certain amount of 1,2,4-triazole-1,3-disulfonamide derivatives. Hydrazones have obtained extensive attention in the field of pharmaceutical due to its unique chemical structure and remarkable activity (insecticidal, antibacterial, antifungal and herbicidal). By means of coupling numerous hydrazone with triazole sulfonyl chloride groups, 24 novel derivatives were synthesized. Spectrum analysis of LC-MS, 1H NMR and 13C NMR were used for characterizing these new compounds. Compared with commercial Cyazofamid using bioassays, most of these compounds displayed preferable fungicidal activities. Moreover, compounds 8q illustrated the greatest CDM resistance (EC50 = 7.776 mg/L). Field efficacy trials revealed that compound 8q fungicidal activity was higher than the purchased agrochemical Cyazofamid and Amisulbrom. Thus, the research declared that 8q displayed a great potential for the application of fungicide against CDM. 相似文献
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Sandip Gurav Anitha Police Mohd Zainuddin Ravindra Ramachandra Punde Purushottam Dewang Chandregowda V Raghava Reddy Kethiri Sriram Rajagopal Ramesh Mullangi 《Biomedical chromatography : BMC》2013,27(2):164-171
A highly sensitive, specific and enantioselective assay has been developed and validated for the estimation of TAK‐700 enantiomers [(+)‐TAK‐700 and (?)‐TAK‐700] in rat plasma on LC‐MS/MS‐ESI in the positive‐ion mode. Liquid–liquid extraction was used to extract (±)‐TAK‐700 enantiomers and IS (phenacetin) from rat plasma. TAK‐700 enantiomers were separated using methanol and 5 mm ammonium acetate (80:20, v/v) at a flow rate of 0.7 mL/min on a Chiralcel OJ‐RH column. The total run time was 7.0 min and the elution of (+)‐TAK‐700, (?)‐TAK‐700 and IS occurred at 3.71, 4.45 and 4.33 min, respectively. The MS/MS ion transitions monitored were m/z 308.2 → 95.0 for TAK‐700 and m/z 180.2 → 110.1 for IS. The standard curves for TAK‐700 enantiomers were linear (r2 > 0.998) in the concentration range 2.01–2015 ng/mL for each enantiomer. The inter‐ and intra‐day precisions were in the ranges 3.74–7.61 and 2.06–8.71% and 3.59–9.00 and 2.32–11.0% for (+)‐TAK‐700 and (?)‐TAK‐700, respectively. Both the enantiomers were found to be stable in a battery of stability studies. This novel method was applied to the study of stereoselective oral pharmacokinetics of (+)‐TAK‐700 and it was unequivocally demonstrated that (+)‐TAK‐700 does not undergo chiral inversion to its antipode in vivo. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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以聚丙烯腈为原料,首先通过部分腈基的[3+2]合环反应转化为聚(乙烯基四唑-co-丙烯腈)[Poly(VT-co-AN)],再通过碱性水解反应将剩余的腈基转化为羧基,合成出聚(乙烯基四唑-co-丙烯酸)[Poly(VT-co-AA)]。 采用傅里叶红外变换光谱仪(FT-IR)、核磁共振碳谱仪(13C NMR)、酸碱滴定等方法对Poly(VT-co-AN)和[Poly(VT-co-AA)的结构进行了表征,结果表明,Poly(VT-co-AN)的分子链中含有腈基、四唑基团和部分羧基,四唑基团的含量为68.6%,与酸碱滴定法测定的四唑基团的含量相近,[Poly(VT-co-AA)中含有四唑基团和羧基,不含有腈基,酸值高于Poly(VT-co-AN),四唑基团的含量为67.6%,与叠氮化钠与聚丙烯腈的摩尔比相近。 热失重分析结果显示[Poly(VT-co-AA)的热分解速率加快,在270~285 ℃的温度区间内分解完全。 相似文献
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S. Vijay Kumar G. Rudresha Sandip Gurav Mohd Zainuddin Purushottam Dewang Raghava Reddy Kethiri Sriram Rajagopal Ramesh Mullangi 《Biomedical chromatography : BMC》2013,27(2):203-207
A novel, simple, specific, sensitive and reproducible high‐performance liquid chromatography (HPLC) assay method has been developed and validated for the estimation of abiraterone (ART) in rat plasma. The analytical procedure involves extraction of ART and diclofenac (internal standard, IS) from rat plasma with a simple liquid–liquid extraction process. The chromatographic analysis was performed on a Waters Alliance system with a Betasil C18 column maintained at ambient room temperature and an isocratic mobile phase [acetonitrile–water–10 mm potassium dihydrogen phosphate (pH 3.0), 55:5:40, v/v/v] at a flow rate of 1.00 mL/min with a total run time of 10 min. The eluate was monitored using an UV detector set at 255 nm. Method validation was performed as per FDA guidelines and the results met the acceptance criteria. The calibration curve was linear over a concentration range of 93.4–3251 ng/mL (r2 = 0.997). The intra‐ and inter‐day precisions were 0.56–4.98 and 3.03–7.18, respectively, in rat plasma. The validated HPLC method was successfully applied to a pharmacokinetic study of ART in rats. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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