Atomic Emission Spectrometry AES

Advantages of AES, relative to flame-AAS, include the lack of a requirement for a radiation source. Collisions within the plasma serve to promote analyte atoms to excited state levels. Additionally, this technique is characterised by linearities of response which span three to four orders of magnitude. Limits of detection for ICP-AES are similar to those obtained with flame-AAS (typically within a factor of 3 to 5 - some elements are shghtly less responsive in flame-AAS others slightly more responsive). ICP-AES does require a fairly high resolution monochromator/detection system to scan carefully across analyte emission lines and to be able to resolve them from the other emissions and from the high luminosity of the torch. There are many spectral 

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Note that the interfacing of LC techniques with MS puts significant constraints on the solvents that can be used i.e., they must be volatile, with a low salt concentration, for MS compatibility. Narrow-bore columns, which use much smaller amounts of salt and organic modifier, appear to have potential for facilitating IEC-MS applications.40 Despite the excellent sensitivity of MS detection for most elements, however, there are cases where matrix effects can interfere. In this situation, combination of IEC with atomic emission spectrometry (AES) or atomic absorption spectrometry (AAS) may be preferable, and can also provide better precision.21 32 4142 Other types of... 

Metals contained in samples are determined by a wide variety of analytical methods. Bulk metals, such as copper in brass or iron in steel, can be analyzed readily by chemical methods such as gravimetry or electrochemistry. However, many metal determinations are for smaller, or trace, quantities. These are determined by various spectroscopic or chromatographic methods, such as atomic absorbance spectrometry using flame (FAAS) or graphite furnace (GFAAS) atomization, atomic emission spectrometry (AES), inductively coupled plasma atomic emission spectrometry (ICP-AES), inductively coupled plasma mass spectrometry (ICP-MS), x-ray fluorescence (XRF), and ion chromatography (IC). 

Atomic emission spectrometry (AES) is also called optical emission spectrometry (OES). It is the oldest atomic spectrometric multielement method which originally involved the use of flame, electric arc or spark excitation. Recently there has been considerable innovation in new sources plasma sources and discharges under reduced pressure. Littlejohn et al. (1991) have reviewed recent advances in the field of atomic emission spectrometry, including fundamental processes and instrumentation. 

By far the most common type of plasma used for speciation analysis is the inductively coupled plasma (ICP) with mass spectrometry (MS) or atomic emission spectrometry (AES) detection. The performance of the ICP-MS system has been well documented since its development in the early 1980s by the Gray and Houk research groups [14,15], and it is now used for a wide variety of applications such as environmental, clinical, geological, food, and industrial analysis. 

The most suitable techniques for the rapid, accurate determination of the elemental content of foods are based on analytical atomic spectrometry, for example, atomic absorption spectrometry (AAS), atomic emission spectrometry (AES), and mass spectrometry, the most popular modes of which are Game (F), electrothermal atomization (ET), and hydride generation (HG) AAS, inductively coupled plasma (ICP), microwave-induced plasma (MIP), direct current plasma (DCP) AES, and ICP-MS. Challenges in the determination of elements in food include a wide range of concentrations, ranging from ng/g to percent levels, in an almost endless combination of analytes with matrix speci be matrices. 

The most important analytical techniques which are used in multielement trace analysis are ICP-MS, atomic absorption spectrometry (AAS) and ICP atomic emission spectrometry (AES). NAA is applied as reference method in order to establish certibed values. The regular atomic spectrometry update on clinical and biological materials, foods and beverages (ASU review) gives an overview of the recent developments in elemental analysis of food and beverages [81]. 

An inductively-coupled plasma (ICP) is an effective spectroscopic excitation source, which in combination with atomic emission spectrometry (AES) is important in inorganic elemental analysis. ICP was also considered as an ion source for MS. An ICP-MS system is a special type of atmospheric-pressure ion source, where the liquid is nebulized into an atmospheric-pressure spray chamber. The larger droplets are separated from the smaller droplets and drained to waste. The aerosol of small droplets is transported by means of argon to the torch, where the ICP is generated and sustained. The analytes are atomized, and ionization of the elements takes place. Ions are sampled through an orifice into an atmospheric-pressure-vacuum interface, similar to an atmospheric-pressure ionization system for LC-MS. LC-ICP-MS is extensively reviewed, e.g., [12]. 

Whatever the analytical method and the determinand may be, the greatest care should be devoted to the proper selection and use of internal standards, careful preparation of blanks and adequate calibration to avoid serious mistakes. Today the Antarctic investigator has access to a multitude of analytical techniques, the scope, detection power and robustness of which were simply unthinkable only two decades ago. For chemical elements they encompass Atomic Absorption Spectrometry (AAS) [with Flame (F) and Electrothermal Atomization (ETA) and Hydride or Cold Vapor (HG or CV) generation]. Atomic Emission Spectrometry (AES) [with Inductively Coupled Plasma (ICP), Spark (S), Flame (F) and Glow Discharge/Hollow Cathode (HC/GD) emission sources], Atomic Fluorescence Spectrometry (AFS) [with HC/GD, Electrodeless Discharge (ED) and Laser Excitation (LE) sources and with the possibility of resorting to the important Isotope... 

The history of atomic emission spectrometry (AES) goes back to Bunsen and Kirchhoff, who reported in 1860 on spectroscopic investigations of the alkali and alkali earth elements with the aid of their spectroscope [1], The elements cesium and rubidium and later on thorium and indium were also discovered on the basis of their atomic emission spectra. From these early beginnings qualitative and quantitative aspects of atomic spectrometry were considered. The occurrence of atomic spectral lines was understood as uniequivocal proof of the presence of these elements in a mixture. Bunsen and Kirchhoff in addition, however, also estimated the amounts of sodium that had to be brought into the flame to give a detectable line emission and therewith gave the basis for quantitative analyses and trace determinations with atomic spectrometry. 

Today, analyses of bulk fossil chemistry are largely conducted by inductively coupled plasma (ICP) atomic emission spectrometry (AES), ICP mass spectrometry (MS) or ICP optical emission spectrometry (OES) techniques (e.g. Rosenthal et al. 1999 DeVilliers et al. 2002 Green et al. 2003). These techniques permit rapid and precise (c. 1% for many elements) measurement of a number of chemical constituents simultaneously. ICP-MS offers higher sensitivities than AES and OES, enabling measurement of more elements and smaller sample sizes. 

Potassium analysis is usually carried out by flame spectrometry. Atomic emission spectrometry (AES) is slightly more sensitive, though atomic absorption spectrometry (AAS) is somewhat more immune to interference. Interferences occur in the presence of high concentrations of sodium and due to the formation of refractory potassium phosphates in the flame. A solution containing 0.4 mmol cesium chloride and 0.15 mmolL lanthanum nitrate dissolved in 0.1 M HCl will reduce both cation enhancement and anionic suppression (Wieland 1992, Birch and Padgham 1993). 

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. 

The determination of iodine in seawater helps in understanding the marine environment. A variety of analytical methods have been proposed for the quantitative determination of iodine in seawater. This chapter discusses the methods employed for the separation and determination of iodine in seawater. These methods include capillary electrophoresis (CE), ion chromatography (IC), high-performance hquid chromatography (HPLC), gas chromatography (GC), spectrophotometry, ion-selective electrode, polar-ography, voltammetry, atomic emission spectrometry (AES), and neutron activation analysis (NAA). The advantages and hmitations of these methods are also assessed and discussed. Since iodine is present in the ocean at trace levels and the matrices of seawater are complex, especially in estuarine and coastal waters, the methods developed for the... 

For judging multielement determination by means of atomic emission spectrometry (AES) or X-ray fluorescence analysis (XRF), the evaluation of the signal-to-background ratio, I to / , for all p signals is proposed. 

Atomic emission spectrometry (AES). An analytical method for the determination of elements in small quantities. It is based on spontaneous emission of free atoms or ions when the excitation is performed by thermal or electric energy. 

Atomic Absorption Spectrometry (AAS) and Atomic Emission Spectrometry (AES)... 

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