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Studying the intermittent stable theorem and the synchronization of a delayed fractional nonlinear system 下载免费PDF全文
In this paper, an intermittent synchronizing delayed fractional nonlinear system is studied. We propose a novel intermittent stable theorem for the delayed fractional system and derive a new synchronization criterion for delayed fractional systems by means of fractional stable theorem and the differential inequality method. Intermittent synchronizing fractional delayed Newton-Leipnik system is taken as an illustrative example and numerical simulation of this example is presented to show the feasibility and effectiveness of the proposed theorem. 相似文献
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用高效液相色谱手性固定相法拆分芳香仲醇及芳香乙二 醇类手性化合物 总被引:4,自引:0,他引:4
在ChiralcelOD和ChiralcelOJ两支多糖类手性固定相上,以各种不同配比的正己烷-异丙醇为洗脱剂对38种带有不同取代基的芳香仲醇及芳香乙二醇类手性化合物的对映体进行拆分,考察了这些外消旋体在这两支手性柱上的色谱行为。结果表明,扬长避短一柱对这些化合物的拆分能力与化合物取代基的性质和位置有关,这些化合物与手性固定相之间的氢键作用和π-π作用是影响手性拆分的重要原因。拆分方法已应用于潜手性酮不对称还原产物的光学纯度的鉴定,并取得了很好的效果。 相似文献
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Two remarkable reducing agents NaBH_4 (or NaBD_4)/SnCl_2(orSnCl_4·2Et_2O) with chiral ligands are applied to the asymmetricreduction of carbonyl compounds with excellent chemical yieldsand enantioselective excesses. 相似文献
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