文档介绍：Chapter 2 Gas Chromatography(GC)
§2-1 Summary
●Chromatographic separation technique(色谱分离): A separation technique based on partition of 2 or more substances in a mixture in two phases(色谱法、色层法、层析法,chromatographer)
● Chromatographic analysis(色谱分析):
Chromatographic separation applied on analytical chemistry
Advantages: High separation efficiency, high detection efficiency, fast analytical velocity
GC
●Mobile phase & Stationary phase(流动相与固定相): Chromatographic separation involving partition of different species in a mixture in two phases, among which one phase (solid or liquid) does not move (stationary phase) , the other phase (gas or liquid) takes the sample mixture to pass through the stationary phase packed in the column( mobile phase)
Separations are affected due to the differences of substances’ affinities for a mobile phase and a stationary phase(分离原理).
GC
Gas supply
Flow controller
Oven
Column
To waste
Detector
Flow meter
(In one of these positions)
Injection
system
Amplifier
Integrator
Recorder
GC
皂膜流量计
转字流量计
调整仪,标准仪
Setup of Gas Chromatograph
GC
inert gases wothout interaction with analytes or stationary phase
管状的
Thermal conductivity detector
Electron capture detector
, IR, FPD
Flame photometric detector
Hydrogen flame ionization detector
Chromatogram of xylene isomers on a polar column
GC
Y
GC
0
12
4
Peak width at a half height
Peak width at peak base
Adjusted retention time
Rotention time
Dead
time
Air peak

1/2
h
2
s
Y
1/2
Y
t'
R
t
R
t
M
Injection
t
Response signal
Chromatogram
Time(arbitrary units)
Nomenclature of Chromatographic separation
●Chromatographic Curve & Chromatogram The chart of output detector response (concentration) versus time
The protuberance in the curve is called chromatographic peak
如果进样量很小,浓度很低,在吸附等温线(气固吸附色谱)或分配等温线(气液分配色谱)的线性范围内,则色谱峰是对称的。