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Weak plasma coupling

If an analytic fit to the measured cross-section data is available, the reaction rates (erv) (Maxwellian averages) can easily be calculated for weak plasma coupling approximation as... [Pg.323]

Inductively coupled plasma-mass spectrometry (ICP-MS) has seen increasing use in trace element studies of ceramics in the last two decades. While early work using weak acid extraction proved problematic (/), recent work by Kennet et al. using microwave digestion (2) and by Larson et al. using laser ablation (3) have yielded considerable advances in the application of this technique. [Pg.350]

In this paper we demonstrate that the drag resistivity between weakly coupled wires is dominated by the forward scattering in a wide temperature range. Even for identical wires, which is the most favorable for backscattering case, ro oc T2 wins over r2kF at all T above T ep(lo/hkF )1/(1+7. For different wires, r2kF is exponentially small at T < udn, whereas ro has a power-law low-temperature asymptotics here Sn is the mismatch of the electron densities between the wires and u is the characteristic plasma velocity hereafter we sc I, h 1. [Pg.120]

Table 13.2 shows the concentrations of Cu2+ in tap water and lake water determined by the MPA-Gly-Gly-His modified electrode and compared with those of inductively coupled plasma mass spectrometry (ICP-MS). The measured concentration of Cu2+ in tap water when dilutions were accounted for using the MPA-Gly-Gly-His modified electrode was 0.55 +0.08 pM (95% confidence interval). This value is much lower than the copper concentration measured by ICP-MS of 1.70+0.15 pM (95% confidence interval). The peptide-modified electrode measures free Cu2+ or weakly bound copper complexes rather than the total metal-ion concentration measured by ICP-MS. Hence the use of peptides has the ability to measure metal-ion bioavailability for specific species. The results are consistent with others who have also shown that the labile fraction of copper is much less than the total copper [7]. [Pg.1053]

From this expression one can calculate r for a density n = y and temperature T. T < 1 corresponds to the case of a weakly coupled plasma and r > 1 corresponds to a strongly coupled plasma. Ultracold neutral plasmas can be in the borderline of the strongly coupled plasma domain [61]. Typical examples of weakly coupled plasmas are those occurring in gaseous... [Pg.118]

Investigations on the doubly excited states of two electron systems under weakly coupled plasma have been performed by several authors. Such states usually occur as resonance states in electron atom collisions and are usually autoionizing [225]. Many of these states appear in solar flare and corona [226,227] and contribute significantly to the excitation cross-sections required to determine the rate coefficients for transitions between ionic states in a high temperature plasma. These are particularly important for dielectronic recombination processes which occur in low density high temperature plasma, occurring e.g. in solar corona. Coronal equilibrium is usually guided by the balance between the rates of different ionization and... [Pg.159]

It has been shown that the major part of Ca and Mg are found in the soluble fraction (whey) of human milk, whereas only small amounts are present in insoluble caseins or in fat [11-13]. Calcium and Mg speciation studies in milk whey using size exclusion chromatography (SEC) combined with inductively coupled plasma atomic emission spectrometry (ICP-AES) [14] indicated that they were preferably associated with the milk nonprotein fraction. A further work [15] showed similar chromatographic profiles by SEC hyphenated with inductively coupled plasma mass spectrometry (ICP-MS), with Ca and Mg eluting in the lowmolecular-weight region (LMW) (<1.4 kDa). Thus, there seem to be weak associations, if any, of Ca2+ or Mg2+ with higher molecular mass biocompounds of milk. [Pg.543]

Inductively coupled plasma mass spectrometry (ICP-MS) is one of the most significant analytical advances to occur in the last 20 years as it allows multielement analysis of solutions and solids to be performed at subnanogram concentrations. Instrumental advances have occurred such that Quadrupole (Q) ICP-MS units are now in routine use in many laboratories. In this chapter, the use of Q-ICP-MS and high performance liquid chromatography (HPLC)-ICP-MS is discussed as regards the quantification of total As and As species in seafood. To highlight the strengths and weaknesses of the use of ICP-MS, data are used that were mainly produced in the laboratories of the authors of this chapter. [Pg.569]


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See also in sourсe #XX -- [ Pg.323 ]




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Weak coupling

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