Direct current plasma atomic emission spectrometry

DCP-AES Direct-current plasma atomic emission spectrometry... 

Many of the analytical methods for detecting vanadium in biological samples have also been used to measure vanadium in environmental samples. They are detailed in Table 6-2. These include GFAAS, spectrophotometry, IDMS, and ICP-AES. Other techniques employed for measuring vanadium in environmental samples are flame atomic absorption spectrometry (FAAS) and direct current plasma- atomic emission spectrometry (DCP-AES). The most widely used methods utilize some modification of atomic absorption spectrometry (AAS). In general, similar methods are employed for preparation and clean up of environmental and biological samples prior to quantification of vanadium (see Section 6.1). 

As mentioned before, two interlaboratory studies were organised prior to certification, involving ca. 15 laboratories using techniques such as cold vapour atomic absorption spectrometry, direct current plasma atomic emission spectrometry (DCP-AES), differential pulse anodic stripping voltammetry (DPASV), microwave plasma atomic emission spectrometry (MIP-AES), electrothermal atomic absorption spectrometry (ETAAS) and neutron activation analysis with radiochemical separation (RNAA). 

Direct Current Plasma Atomic Emission Spectrometry (DCPAES)... 

Techniques under this heading obviously include the most common and popular one of inductively coupled plasma atomic emission spectrometry (IGPAES), also at times simply denoted plasma emission spectrometry, but can also be extended to include direct current plasma atomic emission spectrometry (DGPAES) and graphite furnace IGPAES as well as variants. 

DCP-AES direct current plasma atomic emission spectrometry DCP-OES direct current plasma optical emission spectrometry see DCP-AES DELEIA dissociation-enhanced lanthanide fluoroimmunoassay demyeUnation removal of the myelin sheath of a nerve... 

Panaro, K.W., Erickson, D., and Krull, I.S. (1987) Determination of methylmercury in fish by gas chromatography direct current plasma atomic emission spectrometry. Analyst, 112, 1097-1105. 

The capabilities of direct current plasma atomic emission spectrometry as a powerful IC detection system for As(III) and As(V) was evaluated by Urasa and Ferede [42]. The presence of several common anions was studied. One fundamental drawback of DCP in this particular work appeared to be low sensitivity. But the use of a large sample loop or concentrator column provided improvement. 

GFAAS = graphite furnace (flameless) atomic absorption spectroscopy MCAAS = micro-cup atomic spectroscopy DCOP-AES = direct current plasma-atomic emission spectroscopy HFP-AES = high frequency piasma-torch-atomic emission spectroscopy NAA - neutron activation analyst-, atomic absorption spectroscopy AAS - atomic absorption spectrophotometer XES = X-ray energy spectrometry and SEM - scanning electron microscopy. 

Figure 3.2 Direct-current arc (after G.L. Moore, Introduction to Inductively Coupled Plasma. Atomic Emission Spectrometry, p. 35. C 1989, with the permission of Elsevier Science, Amsterdam).

Despite the absence of any known biological roles for strontium, analysis of trace amounts of the alkali earth metal in many environmental and industrial samples and, especially, in radioactive waste is of critical importance. Techniques applicable for analyzing strontium in environmental or biological material are atomic absorption spectrometry (AAS), inductively coupled plasma atomic emission spectrometry (ICP-AES), direct-current plasma echelle spectrometry, neutron activation analysis and X-ray fluorescence. For most applications, the first two mentioned methods are of interest because, in general, they allow... 

Hydride generation techniques are superior to direct solution analysis in several ways. However, the attraction offered by enhanced detection limits is offset by the relatively few elements to which the technique can be applied, potential interferences, as well as limitations imposed on the sample preparation procedures in that strict adherence to valence states and chemical form must be maintained. Cold-vapor generation of mercury currently provides the most desirable means of quantitation of this element, although detection limits lower than AAS can be achieved when it is coupled to other means of detection (e.g., nondispersive atomic fluorescence or micro-wave induced plasma atomic emission spectrometry). 

Several detectors are used for VOCs analysis by GC flame ionization detector (FID), photo ionization detector (PID), electron capture detector (BCD), electrolytic conductivity detector (ELCD), mass spectrometer detector (MSD or MS), and Fourier-transform infrared detector (FTIRD). For the in-depth reviews of the detectors, readers are directed to Refs. [52-54]. Examples of ICP-MS or microwave-induced plasma atomic emission spectrometry (atomic emission detector, AED) have been reported as detection technique after chromatographic separation [55,56]. Current trends and developments in GC analysis of VOCs have been recently reviewed by the group of Dewulf [16,57]. Mass spectrometer detectors allow low detection limits in single/selected ion monitoring (SIM) and a qualitative confirmation by full scan mode or by means of other ion selected as qualifier. 

The roots of ICP-MS began in the mid-1960s with the advent of a technique called inductively couple plasma—atomic emission spectrometry (ICP-AES). For decades, prior to this, atomic emission spectrometry (flame, direct current-arc, and controUed-waveform spark) was the predominant method used for elemental analysis. The work of Greenfield et al. (1964) and work done essentially simultaneously by Wendt and Fassel (1965) introduced an emission spectrometric technique that provided high sensitivity trace element analysis with a multielement detection capability. This technique is still widely used today and can be studied in publications by Boumans (1987) and Montaser and Golightly (1992). 

Inductively coupled argon plasma (icp) and direct current argon plasma (dcp) atomic emission spectrometry are solution techniques that have been appHed to copper-beryUium, nickel—beryUium, and aluminum—beryUium aUoys, beryUium compounds, and process solutions. The internal reference method, essential in spark source emission spectrometry, is also useful in minimizing drift in plasma emission spectrometry (17). Electrothermal (graphite... 

Emission Spectrometry DCPAES = Direct Current Plasma Emission Spectrometry FAFS = Flame Atomic Fluorescence Spectrometry FAAS = Flame Atomic Absorption Spectrometry. 

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. 

As shown in Table 28-1, several methods are used to atomize samples for atomic spectroscopic studies. Inductively coupled plasmas, flames, and electrothermal atomizers are the most widely used atomization methods we consider these three methods as well as direct current plasmas in this chapter. Flames and electrothermal atomizers are widely used in atomic absorption spectrometry, while the inductively coupled plasma is employed in optical emission and in atomic mass spectrometry. 

Inductively coupled plasma (ICP) and direct current plasma (DCP) atomic emission spectrometry have become widely accepted techniques for simultaneous multielemental analysis. These techniques are highly sensitive and have a very wide dynamic range. A wealth of information is contained in the emission signal, including several atomic and ionic emission lines for each element in the sample. In even the simplest sample, there are thousands of observable spectral lines. To make full use of this enormous spectral information the analyst requires an instrument capable of observing a very wide spectral range simultaneously, preferably from 190 nM to 800 nM with a resolution of approximately 0.01 nM. 

Lajunen. L.H.J., Kinnunen, A. and Yrjnheikki, E. (1985) Determination of mercury in biood and fish samples by cold-vapor atomic absorption and direct current plasma emission spectrometry. At. Spectrosc., 6,49-52. 

In the 1980s and 1990s, some progress has been made in the use of analytical techniques for determining Mo in soils and crops. It has not been researched as extensively as other micronutrients because its deficiency is not as widespread as those of the other micronutrients. In addition to the colorimetric methods used in the past, it can now be successfully analyzed by graphite-furnace atomic-absorption spectrometry and direct-current plasma-emission spectrometry. 

The three universal extractants, ammonium carbonate, ammonium acetate, and AB-DTPA, have an advantage in that the extracts can be read directly for their Mo concentrations by graphite-furnace atomic-absorption spectrometry, direct-current plasma-emission spectrometry. 

Inductively coupled plasma-atomic emission spectroscopy (ICP-AES) is used for multi-element determinations in blood and tissue samples. Detection in urine samples requires extraction of the metals with a polydithiocarbamate resin prior to digestion and analysis (NIOSH 1984a). Other satisfactory analytical methods include direct current plasma emission spectroscopy and determination by AAS, and inductively coupled argon plasma spectroscopy-mass spectrometry (ICP-MS) (Patterson et al. 1992 Shaw et al. 1982). Flow injection analysis (FIA) has been used to determine very low levels of zinc in muscle tissue. This method provides very high sensitivity, low detection limits (3 ng/mL), good precision, and high selectivity at trace levels (Fernandez et al. 1992b). 

The use of atomic emission spectrometry expanded markedly when the first commercial plasma atomic emission spectrometers came on the market in the middle of the seventies. The principle of the direct current plasma (DCP) source was reported in the twenties and the first DCP instrument was constructed at the end of the fifties. The first microwave plasma source was... 

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