A-Level考试化学必看知识点:质谱仪工作原理
A-Level考试中有关化学的部分你复习的怎么样了?今天小编就带来A-Level考试化学必看知识点:质谱仪工作原理的介绍,希望对大家有所帮助。
质谱仪的基本结构包括:
★ Probe 探针
★ Slits 狭缝
★ Magnet 磁板
★ Flight tube 飞行版
★ vacuum pump 真空泵
★ detector slits 检测狭缝
★ detector 检测器
★ accelerator plate 加速板
质谱仪的工作原理
1. Ionisation
电离作用
A sample of an element is vapourised and injected into the mass spectrometer where a high voltage is passed over the chamber.
将一个元素的样品汽化并注入质谱仪,在质谱仪中使其高压通过腔室。
This causes electrons to be removed from the atoms (it is ionised) leaving +1 charged ions in the chamber.
这导致电子被从原子中移除(它被电离),在电离室中留下+1带电离子。
2. Acceleration
加速过程
These positively charged ions are then accelerated towards a negatively charged detection plate.
然后这些带正电荷的离子被加速到带负电荷的检测板上。
3.Ion Drift
离子偏移
The ions are then deflected by a magnetic field into a curved path. The radius of their path is dependant on the charge and mass of the ion.
这些离子被磁场偏转成一条弯曲的路径。它们的半径取决于离子的电荷和质量。
4. Detection
检测
When the positive ions hit the negatively charged detection plate, they gain an electron producing a flow of charge. The greater the abundance, the greater the current produced.
当正离子撞击带负电荷的探测板时,它们获得一个电子,产生电荷流。离子的含量越高,产生的电流就越大。
5. Analysis
分析
These current values are then used in combination with the flight times to produce a spectra print-out with the relative abundance of each isotope displayed.
然后,将这些电流值与飞行时间结合使用,生成显示各同位素相对丰度的光谱图。
以上就是关于A-Level考试化学质谱仪工作原理的简单介绍了,了解alevel考试培训、alevel考试报名的相关问题,可咨询留学经验网。