Inductively coupled plasma generation

How are glow discharge plasma and inductively coupled plasma generated 7.4. What makes resonance ionization a highly selective ionization technique ... 

The inductively coupled plasma [19] is excited by an electric field which is generated by an RF current in an inductor. The changing magnetic field of this inductor induces an electric field in which tire plasma electrons are accelerated. The helicon discharge [20] is a special type of inductively coupled RF discharge. 

Numerous methods have been pubUshed for the determination of trace amounts of tellurium (33—42). Instmmental analytical methods (qv) used to determine trace amounts of tellurium include atomic absorption spectrometry, flame, graphite furnace, and hydride generation inductively coupled argon plasma optical emission spectrometry inductively coupled plasma mass spectrometry neutron activation analysis and spectrophotometry (see Mass spectrometry Spectroscopy, optical). Other instmmental methods include polarography, potentiometry, emission spectroscopy, x-ray diffraction, and x-ray fluorescence. 

One way to fabricate such a reactor is by deep reactive ion etching (DRIE) with a time-multiplexed inductively coupled plasma etcher (most details on fabrication are given in [77]) [7, 77, 78]. Regions of major importance such as the retainers are etched through to avoid differences in stmctural depth which may cause uneven flow. To generate various channel depths in one design, both front-side and back-... 

Inductively coupled plasma Plasmas generated by application of radiofrequency power to a nonresonant inductive coil and maintained by an inductive electromagnetic field. Low-pressure ICP is a high-density plasma source. 

Method abbreviations D-AT-FAAS (derivative flame AAS with atom trapping), ETAAS (electrothermal AAS), GC (gas chromatography), HGAAS (hydride generation AAS), HR-ICP-MS (high resolution inductively coupled plasma mass spectrometry), ICP-AES (inductively coupled plasma atomic emission spectrometry), ICP-MS (inductively coupled plasma mass spectrometry), TXRF (total reflection X-ray fluorescence spectrometry), Q-ICP-MS (quadrapole inductively coupled plasma mass spectrometry)... 

Creed et al. [68] described a hydride generation inductively coupled plasma mass spectrometric method featuring a tubular membrane gas-liquid separator for the determination of down to 100 pg of arsenic in seawater. 

Klane and Blum [69] showed that inductively coupled plasma spectrometry was able to determine below 1000 ng/1 of arsenic in seawater. Ion exclusion chromatography coupled with inductively coupled plasma mass spectrometry has been used to determine several arsenic species in seawater [ 947 ]. Down to 3 ng/1 arsenic can be determined using hydride generation prior to this technique. 

It has been reported that the differential determination of arsenic [36-41] and also antimony [42,43] is possible by hydride generation-atomic absorption spectrophotometry. The HGA-AS is a simple and sensitive method for the determination of elements which form gaseous hydrides [35,44-47] and mg/1 levels of these elements can be determined with high precision by this method. This technique has also been applied to analyses of various samples, utilising automated methods [48-50] and combining various kinds of detection methods, such as gas chromatography [51], atomic fluorescence spectrometry [52,53], and inductively coupled plasma emission spectrometry [47]. 

Hydride generation inductively coupled plasma atomic emission spectrometry... 

The current generation of inductively coupled plasma emission spectrometers provide limits of detection in the range of 0.1-500pg L 1 in solution, a substantial degree of freedom from interferences and a capability for simultaneous multi-element determination facilitated by a directly proportional response between the signal and the concentration of the analyte over a range of about five orders of magnitude. 

Brzezinska-Paudyn et al. [124] compared results obtained in determinations of arsenic by conventional atomic emission spectrometry, flow-injection/hydride generation inductively coupled plasma atomic... 

These workers used an ARC 34000 inductively coupled plasma emission spectrometer with flow-injection hydride generation. The 189.04nm line (3nd order) was used for arsenic measurement. The flow-injection block and Buckler peristaltic pump, as described by Liversage et al. [125] were also used for the determination of arsenic by hydride generation. 

Inductively coupled plasma atomic emission spectrometric analysis with flow-injection/hydride generation... 

These methods were used to determine arsenic in certified sediments (Table 12.15). Conventional inductively coupled plasma atomic emission spectrometry is satisfactory for all types of samples, but its usefulness was limited to concentrations of arsenic greater than 5pg g-1 dry weight. Better detection limits were achieved using the flow-injection-hydride generation inductively coupled plasma technique in which a coefficient of variation of about 2% for concentrations of lOpg g 1 were achieved. 

All four dissolution procedures studied were found to be suitable for arsenic determinations in biological marine samples, but only one (potassium hydroxide fusion) yielded accurate results for antimony in marine sediments and only two (sodium hydroxide fusion or a nitricperchloric-hydrofluoric acid digestion in sealed Teflon vessels) were appropriate for determination of selenium in marine sediments. Thus, the development of a single procedure for the simultaneous determination of arsenic, antimony and selenium (and perhaps other hydride-forming elements) in marine materials by hydride generation inductively coupled plasma atomic emission spectrometry requires careful consideration not only of the oxidation-reduction chemistry of these elements and its influence on the hydride generation process but also of the chemistry of dissolution of these elements. 

Turner IL, Montaser (1998) Plasma generation in ICPMS. In Inductively Coupled Plasma Mass Spectrometry. Montaser A (ed),. Wiley-VCH, New York, p 265-334... 

The observed range of natural variations of 5 Ca is about 4 to 5%o in terrestrial materials and up to 50%o in high temperature condensate minerals in carbonaceous chondrites. The typical reproducibility of measurements is about +0.15%o. Broader application of Ca isotope measurements in geochemistry may be possible, particularly if the reproducibility can be improved to 0.05%o to 0.03%o. There is hope that this can be achieved either with inductively coupled plasma source mass spectrometry (Halicz et al. 1999) or with a new generation of multi-collector thermal ionization mass spectrometers (Heuser et al. 2002). 

Rouxel O, Ludden J, Carginan J, Marin L, Fouquet Y (2002) Natural variations of Se isotopic composition determined by hydride generation multiple collector inductively coupled plasma mass spectrometry. Geochim Cosmochim Acta 66(18) 3191-3199... 

Inductively Coupled Plasma Atomic Emission Spectrometry 4.4.1 Plasma Generation... 

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