Neptune MC-ICP

FIGURE 31.6 Schematic diagram showing the structure of the Neptune MC-ICP-MS used for U-Pb zircon geochronology. 

Figure 5.1 Typical bias in isotope amount ratio measurement resuits using a Neptune MC-ICP-MS instrument. Isotope ratios N( E)/N( E) are considered here.

Figure S.2 Departure from Russell s law of mass bias for isotope amount ratio measurement results using a Neptune MC-ICP-MS instrument. Isotope amount ratios N ° Hg)/N( Hg) and N( ° TI)/N( ° TI) are considered here [Eq. (5.21)]. Agreement with Russell s law would result in/Hg/jfi = l. Uncertainties are quoted with the coverage factor/c=l.

Dzurko et al. [12] determined compound-spedfic Hg isotope ratios using GC interfaced with MC-ICP-MS (Table 17.1). The procedure consists of (i) species extraction based on ethylation, followed by preconcentration of the species thus obtained on a Tenax trap, (ii) thermal desorption of these Hg species and separation using a home-made GC unit, and (iii) registration of the isotope ratios in Hg species using a Neptune MC-ICP-MS instrument. Thallium was introduced... 

HPLC has been coupled to the Neptune MC-ICP-MS, and a significant drift of the point-to-point isotope ratios during peak elution for the measurement of the uranium isotope ratio 235u/238u detected. To evaluate the reason for this drift, injections of the same sample via HPLC and via a flow injection system were compared. For both kinds of sample introduction, the drift in isotope ratio development during peak elution showed the same order of magnitude thus, chromatographic fractionation on the HPLC colunm was excluded as the major source. It was stated that the observed isotope ratio drift is supposedly due to an instrumental shift in mass bias over the peak width. °... 

Figure 4.8 Multiple ion collector array from MC-ICP-MS NEPTUNE and MC-TIMS TRITON (Thermo Fisher Scientific, Bremen). Miniaturized ion counters identical in size to Faraday detectors are mounted in the high mass range to detect, e.g., low-abundance uranium isotopes. (Reproduced by permission of Thermo Fisher Scientific, Bremen.)...

Figure 5.12 MC-ICP-MS a) Plasma 54 (with called S configuration ), from VC Elemental (M. E. Wieser and]. B. Schwieters, Int. /. Mass Spectrom., 242, 97 (2005). Reproduced by permission of Elsevier), b) Nu Plasma from Nu instruments (Reproduced by permission of NU Instruments Ltd) c) Isoprobe from CV Instruments (Reproduced by permission of CV Instruments Ltd) d) Neptune from Thermo Fisher Scientific (Reproduced by permission of Thermo Fisher Scientific, Bremen) e) Nu 1700 (Reproduced by permission of NU Instruments Ltd).

Zircon grain LA-MC-ICP-MS (Neptune) NewWave 2D , 206 0.22 geology Bouman et al.152... 

Human blood liver, muscle MC-ICP-MS (Neptune) separation by anion exchange chromatography 54 Fe, 56Fe, 57Fe 56Fe-0.0049% 57Fe-0.0071 % Walczyk et a/.45... 

TIMS) by Walczyk and von Blanckenburg.23 Precise iron isotope ratio measurements of iron from whole blood matrix by MC-ICP-MS (Neptune, Thermo Fisher Scientific) after microwave digestion and ashing decomposition, anion exchange and precipitation procedures are discussed by Stenberg et at.46... 

Regelous et al have reported ou the use of the isotope dilutiou techuique (using a Pa spike with a half-life of 26.97 days) for the quantitative measurement of 20 fg of protactinium in silicate rocks after chemical separation of the actinide from the rock matrix by MC-ICP-MS (Neptune, Thermo Fisher Scientific, Bremen - equipped with uiue Faraday detectors, oue secondary electron multiplier and a retarding potential quadrupole for high abundance sensitivity measurements). 

In 1996, VG Instruments introduced the Iso-PlasmaTrace multi-collector ICP-MS instrument. Nu Instruments introduced the Nu Plasma on to the market in 1997, which was followed by the large-dispersion Nu Plasma 1700 in 1999. Thermo Optek introduced the VG Axiom Plus MC-ICP-MS unit in 1998. This instrument was equipped with nine Faraday cup detectors and three electron multiplier detectors. Thermo Instruments introduced the Neptune in 2000. At present, there are three commercially available MC-ICP-MS instruments dedicated to isotope ratio analysis the Neptune from ThermoFisher Scientific and the Nu Plasma II and Nu Plasma 1700 from Nu Instruments. Over the past two decades, the number of publications reporting on the use of MC-ICP-MS has grown significantly (Figure 3.3) [8]. 

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