Quantitative analysis optical emission spectrometry

Optical Emission Spectrometry. Principles of Quantitative Analysis... 

Owing to the weU-known high sensitivity of optical emission spectrometry, detection limits reach from 10 g g for metals and C, S, P, B to 10 g g for elements such as H, O, N, considering instantaneous analysis. For quantitative analysis using calibration standards, accuracy 0.2 1 at.%, has been reported for thin layer analysis. For the bulk analysis one has to expect inferior accuracy in the 5—10% range, also for the general case of instantaneous in-depth analysis. 

As in other more mature trace element techniques such as atomic absorption (AA) and inductively coupled plasma optical emission spectrometry (ICP-OES), quantitative analysis in ICP-MS is the fundamental tool used to determine analyte concentrations in unknown samples. In this mode of operation, the instrument is calibrated by measuring the intensity for all elements of interest in a number of known calibration standards that represent a range of concentrations likely to be encountered in your unknown samples. When the full range of calibration standards and blank have been run, the software creates a calibration curve of the measured intensity versus concentration for each element in the standard solutions. Once calibration data are acquired, the unknown samples are analyzed by plotting the intensity of the elements... 

Until the last War, variants of optical emission spectroscopy ( spectrometry when the technique became quantitative) were the principal supplement to wet chemical analysis. In fact, university metallurgy departments routinely employed resident analytical chemists who were primarily experts in wet methods, qualitative and quantitative, and undergraduates received an elementary grounding in these techniques. This has completely vanished now. 

Inductively Coupled and Microwave Induced Plasma Sources for Mass Spectrometry 4 Industrial Analysis with Vibrational Spectroscopy 5 Ionization Methods in Organic Mass Spectrometry 6 Quantitative Millimetre Wavelength Spectrometry 7 Glow Discharge Optical Emission Spectroscopy A Practical Guide 8 Chemometrics in Analytical Spectroscopy, 2nd Edition 9 Raman Spectroscopy in Archaeology and Art History 10 Basic Chemometric Techniques in Atomic Spectroscopy... 

Inorganic pigments and lakes (organic dyes bonded to an inorganic support) can be recognized by the ratio of elements in their composition, making elemental analysis an important tool in their identification. EDS may facilitate an initial qualitative analysis, but quantitative analysis and the detection of trace elements are needed to identify the inorganic colorant components. Due to sample size restrictions, the methods that can be employed are limited. The techniques of inductively-coupled plasma mass spectrometry (ICP-MS), ICP-optical emission spectroscopy (ICP-OES), and laser ablation ICP-MS are described in the literature (56). 

Atomic spectroscopy is the oldest instrumental elemental analysis principle, the origins of which go back to the work of Bunsen and Kirchhoff in the mid-19th century [1], Their work showed how the optical radiation emitted from flames is characteristic of the elements present in the flame gases or introduced into the burning flame by various means. It had also already been observed that the intensities of the element-specific features in the spectra, namely the atomic spectral lines, changed with the amount of elemental species present. Thus the basis for both qualitative and quantitative analysis with atomic emission spectrometry was discovered. These discoveries were made possible by the availability of dispersing media such as prisms, which allowed the radiation to be spectrally resolved and the line spectra of the elements to be produced. 

This chapter deals with optical atomic, emission spectrometry (AES). Generally, the atomizers listed in Table 8-1 not only convert the component of samples to atoms or elementary ions but, in the process, excite a fraction of these species to higher electronic stales.. 4, the excited species rapidly relax back to lower states, ultraviolet and visible line spectra arise that are useful for qualitative ant quantitative elemental analysis. Plasma sources have become, the most important and most widely used sources for AES. These devices, including the popular inductively coupled plasma source, are discussedfirst in this chapter. Then, emission spectroscopy based on electric arc and electric spark atomization and excitation is described. Historically, arc and spark sources were quite important in emission spectrometry, and they still have important applications for the determination of some metallic elements. Finally several miscellaneous atomic emission source.s, including jlanies, glow discharges, and lasers are presented. 

Various techniques can be used for quantitative analysis of chemical composition, including (i) optical atomic spectroscopy (atomic absorption, atomic emission, and atomic fluorescence), (ii) X-ray fluorescence spectroscopy, (iii) mass spectrometry, (iv) electrochemistry, and (v) nuclear and radioisotope analysis [41]. Among these, optical atomic spectroscopy, involving atomic absorption (AA) or atomic emission (AE), has been the most widely used for chemical analysis of ceramic powders. It can be used to determine the contents of both major and minor elements, as well as trace elements, because of its high precision and low detection limits. 

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