Atomic Emission Spectroscopy AES

ICP-AES is often used to determine the concentrations of various elements in a sample. However, an element may be present in a variety of chemical forms or species. By coupling an ICP-AES detector to an ion hromatographic column, a more complete description of the sample species can be obtained. Such a coupling generally requires a nebulizer to introduce the column effluent into the ICP. Conventional pneumatic nebulizers operate at about 1 mL min sample flow and may introduce as Utde as 1% of the sample into the plasma. A newer direct-injection nebulizer (DIN) operates at sample flow rates only 5 to 10% that of a conventional nebulizer [31]. 

The separation of various arsenic species is a good example of the application of ICP-AES detection to anion chromatography [32]. A microbore column 10 cm X 1.7 mm i.d. was used with a low flow rate ( 100 mL min ). The column was packed with a low-capacity anion-exchange material (0.05 mequiv g and solution containing 5 mM ammonium carbonate and 5 mM ammonium bicarbonate at pH 8.6) served as the mobile phase. The column hardware was connected directly to the inlet of the DIN-ICP-AES via a short length of 0.3mm i.d. PEEK tubing. 

0 mM ammonium carbonate/5.0 mM ammonium bicarbonate eluent was used at 80 pL/min flow rate and a 10 pL sample volume. Peaks (in order) As(lll), MMA, As(V) 

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The most appropriate experimental procedure is to treat the metal in UHV, controlling the state of the surface with spectroscopic techniques (low-energy electron diffraction, LEED atomic emission spectroscopy, AES), followed by rapid and protected transfer into the electrochemical cell. This assemblage is definitely appropriate for comparing UHV and electrochemical experiments. However, the effect of the contact with the solution must always be checked, possibly with a backward transfer. These aspects are discussed in further detail for specific metals later on. 

Atomic emission spectroscopy (AES) studies on these materials show a boron content of approximately 28.8%. Because of the dilution effects of the vinyl/phenyl... 

Both atomic emission spectroscopy (AES) and atomic absorption spectroscopy (AAS) are used to identify and quantify the elements present in a sample. 

Such a concentration is at the limit of the method based upon counting yet nonetheless is reliable for atomic emission spectroscopy (AES). 

A number of analytical methods were developed for determination of elemental mercury. The methods are reviewed in Refs. [1-4]. They include traditional analytical techniques, such as atomic adsorption spectroscopy (AAS), atomic fluorescence spectroscopy (AFS), and atomic emission spectroscopy (AES). The AAS is based on measurements of optical adsorption at 253.7 or 184.9 nm. Typical value of the detection limit without pre-concentration step is over 1 pg/l. The AEF is much more sensitive and allows one to detect less than 0.1ng/l of mercury... 

Table 11.5 Detection Limits (ng/mL = ppb) for Selected Elements by Atomic Absorption Spectroscopy (AAS), Atomic Emission Spectroscopy (AES), and Atomic Fluorescence Spectroscopy (AFS) [6]...

Atomic spectroscopy is a quantitative technique used for the determination of metals in samples. Atomic spectroscopy is characterized by two main techniques atomic absorption spectroscopy and atomic emission spectroscopy. Atomic absorption spectroscopy (AAS) is normally carried out with a flame (FAAS), although other devices can be used. Atomic emission spectroscopy (AES) is typified by the use of a flame photometer (p. 168) or an inductively coupled plasma. The flame photometer is normally used for elements in groups I and II of the Periodic Table only, i.e. alkali and alkali earth metals. 

The methods officially used in the wine trade transactions are summarized in Table 8.1. Generally, the OIV methods are officially adopted in the European Union without significant technical changes. The methods reported are mainly colorimetric, titrimetric, or use Atomic Emission Spectroscopy (AES, e.g. Flame Spectrophotometry), Atomic Absorption Spectroscopy (AAS), Hydride Generation-AAS (HG-AAS), Electrothermal-AAS (ET-AAS) and Vapour Atomic Flourescence Spectrophotometry (VAF). 

Atomic emission The emission of radiation by atoms that have been excited in a plasma, a flame, or an electric arc or spark. Atomic emission spectroscopy (AES) An analytical method based on atomic emission. 

The tests utilized to measure these contaminants and degradation by-products include infrared (IR) spectroscopy, electronic particle counting (PC), Karl Fischer titration (KFT), atomic emission spectroscopy (AES) and X-ray fluorescence (XRF) spectroscopy. These methods are available in the form of off-line or at-line benchtop instruments and online/in-line sensors. Most off-line instruments are automated to provide several hundred analyses per day by a single technician. At-line instruments and sensors permit immediate results and diagnostic capabilities. Online sensors can be integrated into machinery control systems to provide real-time monitoring capability. 

The instrumentation used for atomic emission spectroscopy (AES) consists of an atomization cell, a spectrometer/detector and a read-out device. In its simplest form, flame photometry (FP), the atomization cell consists of a flame (e.g. 

The oxidatively adsorbed adlayer of chlorine may be partially reduced to chloride at negative potentials, as shown by LEED and atomic emission spectroscopy (AES) studies... 

Atomic emission spectroscopy (AES) - See Techniques for Materials Characterization, page 12-1. 

Several spectroscopic methods have been used to monitor the levels of heavy metals in man, fossil fuels and environment. They include flame atomic absorption spectrometry (AAS), atomic emission spectroscopy (AES), graphite furnace atomic absorption sp>ectrometry (GFAAS), inductively coupled plasma-atomic emission sp>ectroscopy (ICP/AES), inductively coupled plasma mass spectrometry (ICP/MS), x-ray fluorescence sp>ectroscopy (XRFS), isotope dilution mass spectrometry (IDMS), electrothermal atomic absorption spectrometry (ETAAS) e.t.c. Also other spectroscopic methods have been used for analysis of the quality composition of the alternative fuels such as biodiesel. These include Nuclear magnetic resonance spectroscopy (NMR), Near infrared spectroscopy (NIR), inductively coupled plasma optical emission spectrometry (ICP-OES) e.t.c. 

The most common analytical procedures for measuring cadmium concentrations in biological samples use the methods of atomic absorption spectroscopy (AAS) and atomic emission spectroscopy (AES). Methods of AAS commonly used for cadmium measurement are flame atomic absorption spectroscopy (FAAS) and graphite furnace (or electrothermal) atomic absorption spectroscopy (GFAAS or ETAAS). A method for the direct determination of cadmium in solid biological matrices by slurry sampling ETAAS has been described (Taylor et al., 2000). 

Atomic emission spectroscopy (AES) and atomic absorption spectroscopy (AAS) are In a manner similar to our discussion of molecular spectroscopy, where we compared UV absorption with UV excitation and subsequent fluorescence, these two determinative approaches are the principal ways to identify and quantitate trace concentration levels of metal contamination in the environment. As the need developed to quantitate increasing numbers of chemical elements in the Periodic Table, so too came advances in instrumentation that enabled this to be achieved at lower and lower IDLs AES and AAS techniques are both complementary and competitive. Atomic fluorescence spectroscopy (AFS) is a third approach to trace metal analysis. However, instrumentation for this has not as yet become widespread in environmental testing labs and it is unlikely that one would see atomic or what has become useful x-ray atomic fluorescence spectroscopy. Outside of a brief mention of the configuration for AFS, we will not cover it here. 

ETV may also serve as sample introduction for inductively coupled plasma (ICP)-atomic emission spectroscopy (AES)/MS providing the possibility of in situ sample preparation by selective vaporization of different sample components, using appropriate heating programs. By the reduction/elimination of matrix components, spectral interferences can be minimized and matrix effects in the plasma decreased. 

Atomic spectrometry Laser-induced atomic emission spectroscopy (AES) is a fast technique to determine directly elemental sulfur. Practically no matrix effects occur and the method is virtually nondestructive and easy to use. A disadvantage is the rather poor sensitivity, for example, a typical detection limit for sulfur in steel is 70pgperg. With indirect atomic absorption spectrometry clearly better... 

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