設(shè)為首頁
加入收藏
聯(lián)系我們
一、激發(fā)光源
Excitation light source
1、激發(fā)光源的作用
1, the role of the excitation source
作為光譜分析的光源對試樣都具有兩個(gè)作用：
As the light source of the spectrum analysis, the sample has two functions:
*把試樣中的組分蒸發(fā)、解離為氣態(tài)原子。
* the component in the sample is evaporated and dissociated into a gaseous state.
*使氣態(tài)原子激發(fā)（即光源的主要作用是對試樣的蒸發(fā)、解離和激發(fā)提供所需的能量）。
* the main function of the light source is to provide the energy required for the evaporation, dissociation and excitation of the sample.
2、激發(fā)光源的要求
2, the requirements of the excitation light source
激發(fā)能力強(qiáng)、靈敏度高、穩(wěn)定性好、結(jié)構(gòu)簡單、操作方便、使用安全
Strong excitation ability, high sensitivity, good stability, simple structure, convenient operation and safe use.
3、常用的光源：直流電弧、低壓交流電弧、高壓火花和電感耦合等離子體（ICP）等。
3, commonly used light source: DC arc, low voltage AC arc, high voltage spark and inductively coupled plasma (ICP), etc..
4、光源的選擇
4, the choice of light source
（1）、分析元素的性質(zhì)
(1) the nature of the elements
元素的揮發(fā)性，以及它們的電離電位直接影響該元素的蒸發(fā)和激發(fā)。
The volatility of the elements, and their ionization potentials directly affect the evaporation and excitation of the element.
（2）、分析元素的含量
(2) content of analytical elements
對低含量元素，需要較高的絕對靈敏度，它不僅與激發(fā)溫度有關(guān)，而且與蒸發(fā)溫度有關(guān)。
For low content elements, higher absolute sensitivity is needed. It is not only related to the excitation temperature, but also to the evaporation temperature.
（3）試樣的性質(zhì)
(3) the properties of the sample
（4）、分析任務(wù)
(4) analysis task
5、樣品導(dǎo)入光源的方法：固體自電極法、粉末法、溶液法、氣態(tài)法
5, sample introduction light source method: the solid self electrode method, the powder method, the solution method, the gas method
二、色散儀
Two, dispersion instrument
作用：將光源發(fā)射的不同波長的光色散成為光譜或單色光。
Effect: the light emission at different wavelengths of light dispersion become spectrum or monochromatic light.
分類：按色散器件的不同可分為棱鏡色散儀和光柵色散儀。
Classification: according to the different dispersion device can be divided into prism dispersion instrument and grating dispersion instrument.
構(gòu)造：照明系統(tǒng)、準(zhǔn)光系統(tǒng)、色散系統(tǒng)。
Structure: lighting system, quasi optical system, dispersion system.
三、檢測器
Three, detector
在原子發(fā)射光譜法中，常用的檢測方法有：目視法、攝譜法和光電法。
In the atomic emission spectrometry, the commonly used detection methods are: visual method, spectral method and photoelectric method.
這三種方法基本原理都相同，都是把激發(fā)試樣獲得的復(fù)合光通過入射狹縫照射到分光元件上，使之色散為光譜。然后通過測量譜線而檢測試樣中的分析元素，其區(qū)別就在于目視法用人眼去接受，攝譜法用感光板接受，光電法用光電倍增管接受。目前，廣泛使用的是攝譜法。
The basic principles of the three methods are the same, and the composite light which is obtained by the excitation sample is irradiated to the light splitting element through the entrance slit. And then by measuring the spectral lines and detection of the analysis of the elements in the sample, the difference lies in the visual method with the human eye to accept, the photographic spectrum method with a photographic plate to accept, photoelectric multiplier tube to accept. At present, the widely used is the perturbation method.
