5种生物胺的毛细管胶束电动色谱分离

在胶束电动色谱模式下考察了影响生物胺分离的几个因素(如缓冲溶液及SDS浓度、pH、表面活性剂、分离温度及外加电压等)并优化了分离条件,建立了一种简单快速的利用毛细管胶束电动色谱DAD检测器分离分析生物胺的新方法。当缓冲溶液为40mmol/L硼酸缓冲液(pH8.5)、68mmol/LSDS,分离电压为25kV、分离温度为25℃时,5种生物胺在7min内实现了令人满意的基线分离。在优化的条件下,对其线性范围、检出限和重现性进行了测定。结果表明,生物胺的迁移时间的重现性<0.8%,面积的重现性<4%。     

毛细管胶束电动色谱法测定复方丹参滴丸中三种水溶性成份

在胶束电动色谱模式下考察了影响原儿茶醛、丹参素和原儿茶酸分离的重要因素并优化了关键的分离条件,建立了一种简单快速的利用毛细管胶束电动色谱DAD检测器分离分析原儿茶醛、丹参素、原儿茶酸的新方法.当缓冲溶液为50 mmol/L磷酸盐缓冲液(pH 7.2)和20 mmol/L SDS,分离电压为15 kV和分离温度为25℃时,三种分析物在10 min内实现了基线分离.结果表明,所建立的分离方法的线性范围宽,检出限低,重现性好.并利用该方法测定了复方丹参滴丸中的原儿茶醛和丹参素.     

Observation of the BEC-BCS crossover in a degenerate Fermi gas of lithium atoms

We observe characteristic atomic behaviors in the Bose-Einstein-condensation-Bardeen-Cooper-Schrieffer(BEC-BCS)crossover,by accurately tuning the magnetic field across the Feshbach resonance of lithium atoms.The magnetic field is calibrated by measuring the Zeeman shift of the optical transition.A non-monotonic anisotropic expansion is observed across the Feshbach resonance.The density distribution is explored in different interacting regimes,where a condensate of diatomic molecules forms in the BEC limit with the indication of a bimodal distribution.We also measure the three-body recombination atom loss in the BEC-BCS crossover,and find that the magnetic field of the maximum atom loss is in the BEC limit and gets closer to the Feshbach resonance when decreasing the atom temperature,which agrees with previous experiments and theoretical prediction.This work builds up a controllable platform for the study on the strongly interacting Fermi gas.