排序方式: 共有29条查询结果,搜索用时 15 毫秒
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聚乙烯吡烙烷酮修饰碳糊电极-双通道毛细管电泳安培法测定环境中的硝基酚 总被引:2,自引:0,他引:2
建立了几种硝基酚的聚乙烯吡烙烷酮修饰碳糊电极-双通道毛细管电泳安培检测的新方法.采用双工作电极和两台伏安仪,将样品的检测电位分别设定在氧化电位(+0.5Vvs.SCE)和还原电位(-1.4Vvs.SCE),在一个检测池中同时获得所有样品的氧化和还原信息,以还原电流和氧化电流值之比(Nc=ir/io)作为定性依据,对样品的纯度进行确证.通过优化工作电极、检测电位、缓冲溶液、β-CD和乙醇浓度等实验参数,实现了几种硝基酚的分离检测,同时采用样条小波最小二乘法对样品数据信号进行处理,并将此法应用于实际样品的测定. 相似文献
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Natural product chemistry experiments, which train the students to master the basic skills for extraction, separation and identification of the active components of natural products, and acquaint with the research methods of natural product chemistry, are an important part of organic chemistry laboratory. This paper analyzes the common problems related to the current natural products chemistry laboratories in domestic universities. In recent years, we carried out the reforms of the teaching contents, teaching conditions, and teaching methods. The teaching practices show that the students' learning interest and efficiency, the abilities to analyze and solve problems, and the scientific research abilities have been trained and strengthened. The teachers' experimental teaching level and teaching quality have been greatly improved. 相似文献
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报道了一种测定大黄酸的快速毛细管电泳电化学方法。采用简易制作的一种双通道-双工作电极电化学系统,可以实现电导法和安培法同时检测;优化选择了缓冲介质、工作电极、检测电位、毛细管长度和内径以及分离电压等实验参数,并对提高分析速度进行了初步研究和探讨。结果表明:大黄酸在100s内可以得到较好的分离测定,电导法和安培法的线性范围分别为6.83×10-4~1.07×10-5mol/L和3.41×10-4~2.67×10-6mol/L,最小检出浓度分别为5.28×10-6mol/L和3.16×10-7mol/L。采用设计的双通道 双工作电极检测装置,可以充分发挥电导法和安培法的优越性,对样品峰及样品的纯度进行确证;另外通过采用较短的毛细管与适当提高分离电压,可以提高分析速度。该法已用于中药大黄中大黄酸的测定。 相似文献
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