Quantitative Spectrochemical Analysis

Quantitative spectrochemical analysis usually is considered to have originated about 1882 when W. N. Hartley, in Ireland, used a spark source to determine beryllium. In 1902, de Gramont, in France, used a spark to excite solid samples and used the method for metallurgical analysis. 

---

Chemical Analysis. Plasma oxidation and other reactions often are used to prepare samples for analysis by either wet or dry methods. Plasma excitation is commonly used with atomic emission or absorption spectroscopy for quaUtative and quantitative spectrochemical analysis (86—88). 

X-rays provide an important suite of methods for nondestmctive quantitative spectrochemical analysis for elements of atomic number Z > 12. Spectroscopy iavolving x-ray absorption and emission (269—273) is discussed hereia. X-ray diffraction and electron spectroscopies such as Auger and electron spectroscopy for chemical analysis (esca) or x-ray photoelectron spectroscopy are discussed elsewhere (see X-raytechnology). 

Quantitative Spectrochemical Analysis by the Copper Spark Method. Report CK-2254 (8. Febr. 1945). 

Calibration is one of the most important tasks in quantitative spectrochemical analysis. The subject continues to be extensively examined and discussed in the chemometrics literature as ever more complex chemical systems are studied. The computational procedures discussed in this chapter are concerned with describing quantitative relationships between two or more variables. In particular we are interested in studying how measured independent or response variables vary as a function a single so-called dependent variable. The class of techniques studied is referred to as regression analysis. 

For quantitative spectrochemical analysis, using photographic recording, a densitometer is essential since it permits the measurement of relative spectral line intensities. A densitometer for measuring the opacity of a spectral line should have the following characteristics ... 

Harvey s original work (1947), in which he published k values for 42 elements in 36 different matrices, illustrated the significance of matrix effects on spectrochemical analytical data. If all samples could be reduced to a common matrix, semiquantitative and quantitative spectrochemical analysis could be simplified. A method to accomplish this, in part, involves the addition of another substance to the sample. The added substance is frequently referred to as a spectroscopic buffer and is added in sufficient quantity to become a major constituent of the sample mixture. 

Quantitative spectrochemical analysis has numerous advantages over other analytical techniques and also some disadvantages. The advantages of the method include the following. 

---