Mass thermal ionization

Following the movement of airborne pollutants requires a natural or artificial tracer (a species specific to the source of the airborne pollutants) that can be experimentally measured at sites distant from the source. Limitations placed on the tracer, therefore, governed the design of the experimental procedure. These limitations included cost, the need to detect small quantities of the tracer, and the absence of the tracer from other natural sources. In addition, aerosols are emitted from high-temperature combustion sources that produce an abundance of very reactive species. The tracer, therefore, had to be both thermally and chemically stable. On the basis of these criteria, rare earth isotopes, such as those of Nd, were selected as tracers. The choice of tracer, in turn, dictated the analytical method (thermal ionization mass spectrometry, or TIMS) for measuring the isotopic abundances of... [Pg.7]

Figure 4 Measurements of (A) uranium aetivity ratios, UARs ( U U) and U eoneentrations (B) aeross a salinity gradient off the Amazon River mouth (1996). UARs were determined by thermal ionization mass speetrometry (TIMS) at Calteeh (D. Poreelli) U eoneentrations by ICPMS...

Edwards RL, Cheng H, Murrell MT, Goldstein SJ (1997) Protactinium-231 dating of carbonates by thermal ionization mass spectrometiy imphcations for Quaternary climate change. Science 276 782-785... [Pg.20]

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Bourdon B, Joron J-L, Allegre CJ (1999) A method for Pa analysis by thermal ionization mass spectrometry in silicate rocks. Chem Geol 157 147-151... [Pg.55]

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Neder H, Heusser G, Laubenstein M (2000) Low-level y-ray germanium-spectrometer to measure veiy low primordial radionuclide concentrations. ApplRadiat Isot 53 191-195 Palacz ZA, Freedman PA, Walder AJ (1992) Thorium isotope ratio measurements at high abundance sensitivity using a VG 54-30, an energy-filtered thermal ionization mass spectrometer. Chem Geol 101 157-165... [Pg.58]

Pickett DA, Murrell MT, Williams RW (1994) Determination of femtogram quantities of protactinium in geologic samples by thermal ionization mass spectrometry. Anal Chem 66 1044-1049 Pietruszka AJ, Carlson RW, Hauri EH (2002) Precise and accurate measurement of Ra- °Th- U disequilibria in volcanic rocks using plasma ionization multicollector mass spectrometry. Chem Geol 188 171-191... [Pg.58]

Volpe AM, Olivares JA, Murrell MT (1991) Determination of radium isotope ratios and abundances in geologic samples by thermal ionization mass spectrometiy. Anal Chem 63 913-916... [Pg.59]

Figure 15. Error in age vs. age, both on log scales (after Edwards et al. 1997). Each data point represents data from a particular sample analyzed by thermal ionization mass spectrometric techniques. Solid circles represent Pa ages. Contours of aniytical error in Pa/ U pertain to the Pa data points. Shaded squares represent °Th ages. See text for discussion.

Zhao J-X, Hu K, Collerson KD, Xu H-K (2001) Thermal ionization mass spectrometry U-series dating of a hominid site near Nanjing, China. Geology 29 27-30... [Pg.460]

Poupard D, Jouniaux B. 1990. Determination of picogram quantities of americium and curium by thermal ionization mass spectrometry (TIMS). Radiochim Acta 41(l) 25-28. [Pg.256]

A. Deyhle. Improvements of Boron Isotope Analysis by Positive Thermal Ionization Mass Spectrometry Using Static Multicollection of CS2BO2 Ions. Int. J. Mass Spectrom., 206(2001) 79-89. [Pg.71]

R. Doucelance and G. Manhes. Reevaluation of Precise Lead Isotope Measurements by Thermal Ionization Mass Spectrometry Comparison with Determinations by Plasma Source Mass Spectrometry. Chem. Geol, 176(2001) 361-377. [Pg.71]

J. L. Mann and W. R. Kelly. Measurement of Sulfur Isotope Composition (834S) by Multiple-Collector Thermal Ionization Mass Spectrometry Using a 33S-36S Double Spike. Rapid Commun. Mass Spectrom., 19(2005) 3429-3441. [Pg.71]

M. D. Schmitz, S. A. Bowring, and T. R. Ireland. Evaluation of Duluth Complex Anorthositic Series (AS3) Zircon as a U-Pb Geochronological Standard New High-Precision Isotope Dilution Thermal Ionization Mass Spectrometry Results, Geochim. Cosmochim. Acta, 67(2003) 3665-3672. [Pg.71]

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