Gas/liquid chromatography · 气/液色谱
| English | 中文 | Pinyin · 拼音 |
|---|---|---|
| carrier gas/ˈkærɪə ɡæs/ | 载气 | zài qì |
| retention time/rɪˈtenʃn taɪm/ | 保留时间 | bǎo liú shí jiān |
| chromatogram/krəʊˈmætəɡræm/ | 色谱图 | sè pǔ tú |
| mass spectrometer/mæs spekˈtrɒmɪtə/ | 质谱仪 | zhì pǔ yí |
Separating a vapour
- Gas/liquid chromatography (GLC) separates a mixture of volatile components.
- The mobile phase is a carrier gas 载气; the stationary phase is a liquid on a solid.
- Each component leaves a peak at its own retention time 保留时间.
分离一种蒸气
- 气/液色谱(gas/liquid chromatography, GLC)分离一个挥发性组分的混合物。
- 流动相是一种载气;固定相是一个固体上的液体。
- 每个组分在它自己的保留时间留下一个峰。
Gas/liquid chromatography route · 气/液色谱途径
Follow a volatile sample through column separation to a chromatogram. · 跟随一个挥发性样品通过柱分离到一个色谱图。
In gas chromatography, the time a component takes to pass through the column is its ______ time. · 在气相色谱中,一个组分通过柱所需的时间是它的 ______ 时间。
Used to identify components. · 用于识别组分。
Gas chromatography separates a mixture of volatile substances. · 气相色谱分离一个挥发性物质的混合物。
They travel through the column at different speeds. · 它们以不同的速度通过柱。
How it works
- the stationary phase is a high-boiling-point non-polar liquid on a solid support.
- the mobile phase is an unreactive carrier gas (e.g. nitrogen).
- the retention time is how long a component takes to pass through.
- A component that interacts more with the stationary phase has a longer retention time.
A gas-liquid chromatogram 色谱图 with retention times and peak areas
它如何工作
- 固定相是一个固体支撑物上的高沸点非极性液体。
- 流动相是一种不反应的载气(例如氮)。
- 保留时间(retention time)是一个组分通过所需的时间。
- 一个与固定相相互作用更多的组分有一个更长的保留时间。
一个带保留时间和峰面积的气液色谱图
In GLC, the mobile phase is: · 在 GLC 中,流动相是:
A carrier gas moves the components past the liquid stationary phase. · 一种载气把组分移过液体固定相。
A component that interacts more strongly with the stationary phase has a: · 一个与固定相相互作用更强的组分有一个:
More interaction slows it down, so it takes longer to pass through (longer retention time). · 更多相互作用使它减速,所以它通过需要更长时间(更长的保留时间)。
Reading the chromatogram
- The area of each peak gives the proportion of that component in the mixture.
A chromatogram shows two peaks with areas in the ratio 3 : 1.
- Total = 3 + 1 = 4 parts.
- So the mixture is 75% of the first component and 25% of the second.
(Peak height can mislead — always use the area.)
读色谱图
- 每个峰的面积给出混合物中那个组分的比例。
一个色谱图显示两个峰,面积比为 3 : 1。
- 总计 = 3 + 1 = 4 份。
- 所以混合物是 75% 的第一个组分和 25% 的第二个。
(峰高可能误导——总是用面积。)
The area of each peak in a chromatogram gives: · 一个色谱图中每个峰的面积给出:
Peak area is proportional to the amount, so it gives the percentage composition. · 峰面积与量成正比,所以它给出百分比组成。
Identifying the components
- A peak's retention time matches a known standard run in the same conditions → that names the component.
- Coupling GLC to a mass spectrometer 质谱仪 (GC–MS) confirms each component's identity from its mass spectrum.
- GC–MS is the workhorse of forensics, drug testing and airport security.
识别组分
- 一个峰的保留时间匹配一个在相同条件下运行的已知标准 → 那命名这个组分。
- 把 GLC 耦合到一个**质谱仪(GC–MS)**从它的质谱确认每个组分的身份。
- GC–MS 是法医、药物检测和机场安检的主力。
You've got it
- GLC: mobile phase = carrier gas; stationary phase = a non-polar liquid on a solid
- each component has a retention time; more interaction → longer retention
- the peak area = the proportion of that component (areas 3:1 → 75% : 25%)
- match retention time to a standard to identify; GC–MS confirms it
你掌握了
- GLC:流动相 = 载气;固定相 = 一个固体上的非极性液体
- 每个组分有一个保留时间;更多相互作用 → 更长的保留
- 峰面积 = 那个组分的比例(面积 3:1 → 75% : 25%)
- 把保留时间匹配一个标准以识别;GC–MS 确认它