Cations multi-cation analysis

The determination of aluminium is also discussed under Multi-Cation Analysis of Soils in Sects. 2.55 (inductively coupled plasma atomic emission spectrometry) and 2.55 (emission spectrometry). 

Various other techniques that have applied to the determination of antimony in multi-cation analysis include atomic absorption spectrometry (Sect. 2.55), inductively coupled plasma atomic emission spectrometry (Sect. 2.55), neutron activation analysis (Sect. 2.55) and photon activation analysis (Sect. 2.55). 

The present analysis relies on - and extends - the comprehensive theoretical study of Refs. [23,24] on the multi-state interactions in the manifold of the X — E states of Bz+. Like this recent work, it utilizes an ab initio quantum-dynamical approach. In Refs. [23,24] we have, in addition, identified strong coupling effects between the B — C and B — D electronic states, caused by additional conical intersections between their potential energy surfaces. A whole sequence of stepwise femtosecond internal conversion processes results [24]. Such sequential internal conversion processes are of general importance as is evidenced indirectly by the fluorescence and fragmentation dynamics of organic closed-shell molecules and radical cations [49,50]. It is therefore to be expected that the present approach and results may be of relevance for many other medium-sized molecular systems. 

The study of oxygen diffusion in oxides with mixed-valence 3d-ions presents great interest both in theoretical and practical terms. Such systems with Jahn-Teller (JT) 3d-cations are suitable model objects for analysis of the diffusion process in degenerate or pseudo-degenerate condensed systems. The mechanism of multi-well potential formation has been explored well for JT ions [1,2] and it is possible to give a simple microscopic description of the inter-center interactions and different properties of these systems. The practical interest paid to diffusion properties of the... 

New methodologies for the laboratory analysis of cations and metals include the use of inductively coupled plasma emission spectrometry (ICP/ES) or the combinahon of ICP with mass spectrometry (ICP/MS) (e.g., Ivahnenko et al., 2001). The advantages of plasma techniques include (i) a wide and linear dynamic concen-trahon range (ii) multi-element capabihty and (iii) relatively free of matrix interferences. The use of ion chromatography (1C), gas chromatography (GC), and GC/MS has increased for the analysis of anions and dissolved organics (Barth, 1987 Kharaka and Thordsen, 1992 Ivahnenko et al., 2001). 

This is not the case for both cationic and anionic compounds which are difficult to remove from peptide mixtures even after multi-stage purification. Hence, they can still be present in the final MS analysis step, and this results in significant suppression of ESI-MS peptide ion current (7). 

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