微波合成加速有固相协助的液相反应
2006-08-03 22:23
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资料摘要:
Solid-Assisted Solution Phase Synthesis (SASPS) is a technique where the target molecule is
synthesized in solution and solid-supported molecules are used as reagents, catalysts or
scavengers. Recently this technique has been getting a lot of attention as an alternative to solid
phase organic synthesis (SPOS), since it offers many of the advantages of SPOS in terms of ease of
reaction workup and product purification in addition to the advantages associated with traditional
solution-phase chemistry (e.g. the ease of monitoring the progress of the reaction by simply
applying LC-MS or TLC techniques). A disadvantage of this technique is the relative slow reaction
rate, and many of these reactions are sluggish and require hours for complete conversion. The
advent of Microwave-Assisted Organic Synthesis (MAOS) has helped accelerate these reactions and
the technique is gaining rapid popularity as evidenced by the increasing number of publications on
this topic. The polymer backbones are in general, stable at the high temperatures used with MAOS
for the short periods of time required for most of these reactions. This technique is particularly
well-suited for automation and can easily incorporate in-line purification protocols, such as reagent
and byproduct scavenging and catch-and-release. This introduces the possibility of direct highthroughput
synthesis of compounds with intrinsically high purities suitable for biological screening
without the need for further purification.
相关资料
电池的内阻包括欧姆电阻和极化电阻。在温度恒定的条件下,欧姆电阻基本稳定不变,而极化电阻会随着影响极化水平的因素变动。
欧姆电阻主要由电极材料、电解液、隔膜电阻及集流体、极耳的连接等各部分零件的接触电阻组成,与电池的尺寸、结构、连接方式等有关
我们都知道欧姆电阻可以通过交流阻抗EIS方法测得,但怎样才能从EIS数据中得到准确的欧姆电阻呢?很多人认为是Nyquist图跟横轴的交点,但其实这样读到的欧姆电阻并不准确。
我们可以用分析软件做个模拟电路或者用电子元件搭建一个简单的电路进行分析。
当我们对材料做Tafel极化曲线测试时会不会有这样的疑问:
为什么极化曲线测出来的腐蚀电位跟开路电位偏差大,以至于阳极部分与阴极部分不一样宽?
Zahner Analysis分析EIS数据的拟合步骤
1.打开EIS.ism的数据
2.打开Model Editor
3.创建等效电路或打开已保存的等效电路文件
4.进行拟合
5.查看拟合情况
6.导出拟合结果