Tracer element

Special techniques for experimentation with the actinide elements other than Th and U have been devised because of the potential health ha2ard to the experimenter and the small amounts available (15). In addition, iavestigations are frequently carried out with the substance present ia very low coaceatratioa as a radioactive tracer. Such procedures coatiaue to be used to some exteat with the heaviest actinide elements, where only a few score atoms may be available they were used ia the earHest work for all the transuranium elements. Tracer studies offer a method for obtaining knowledge of oxidation states, formation of complex ions, and the solubiHty of various compounds. These techniques are not appHcable to crystallography, metallurgy, and spectroscopic studies. 

Once the pure mineral powders characterized, 3 mixtures were manually prepared and named ML1, ML2 and ML3. They contain each of the 8 minerals in different proportions reproducing 3 mine tailings falling in the uncertainty zone of the static test used. The 3 synthetic tailings were characterized with the same techniques as for the pure minerals. Cp and Sp weight fractions were evaluated from their chemical element tracers (respectively Cu and Zn) obtained from ICP-AES analysis. Qz, Dol, and Sid samples are considered pure and their percentages in the mixtures are not corrected. Table 1 presents the fraction of each mineral in the three mixtures before and after correction taking into consideration the contamination of Po sample by pyrite and calcite, as previously determined. The corrected mineral proportions are used for calculation of the static test parameters based on... 

Chemistry Basic Elements Tracer and Tracer Technique... 

Lowenthal, D. H., K. R. Wunschel, and K. A. Rahn, Tests of Regional Elemental Tracers of Pollution Aerosols. 1. Distinctness of Regional Signatures, Stability during Transport, and Empirical Validation, Environ. Sci. Techno ., 22, 413-420 (1988). 

Rahn, K. A., and D. H. Lowenthal, Elemental Tracers of Distant Regional Pollution Aerosols, Science, 223, 132-139 (1984). 

Lowenthal D. H. and Rahn K. A. (1985) Regional sources of pollution aerosol at Barrow, Alaska during winter 1979-1980 as deduced from elemental tracer. Atmos. Environ. 19, 1995-2010. 

PIXE analysis of 89 samples of the fine component of the aerosol collected at Campo Icaro (Terra Nova Bay) was used to quantify Ca, Cl, Cu, Fe, K, Mn, Ni, S, Si, Ti and Zn (81). The authors pointed out that contamination from the nearby base cannot be excluded a priori this, however, can be easily estimated by means of elemental tracers such as V. The same research group extended the observations of this type in a later study on the aerosol coarse fraction covering also Al, Br, Co and Cr (82). Elemental concentrations were given, with Co being at the lowest and K at the highest level (0.053 0.030 and 90 100 ng m , respectively). 

McArthur, J.M., Turner, J., Lyons, W.B. Thirlwall, M.F. (1989) Salt sources and water-rock interaction on the Yilgarn Block, Australia isotopic and major element tracers. Applied Geochemistry 4, 79-92. 

Chatham, J. R., R. B. Wanty, and D. Langmuir. 1981. Groundwater prospecting for sandstone-type uranium deposits The merits of mineral-solution equilibria versus single element tracer methods. U.S. Dept, of Energy, Report GJO79-360-E. 197. 

S. Goriely, L. Siess, in From Lithium to Uranium Elemental tracers of early cosmic evolution ed. by V. Hill et al., Proc. of IAU symposium Nr 228, (Cambridge Cambridge University Press), p. 451 (2005)... 

Excluded here are those techniques relating to tracer-level work (below weighable quantity of sample measurement by radioassay only), for the concern here will be with the determination of bulk properties of these elements. Tracer-scale studies usually reveal directly only one property of the element under investigation, that is, its relative preference for one environment over another, or more simply, its phase distribution. Nevertheless, as each new transuranium element was discovered and was available only in trace quantities, a great deal of chemistry was learned by inference from tracer-scale studies, including the identity of oxidation states, approximate values of oxidation or reduction potentials, the composition and stability of complex ions, and relative volatilities. 

The transport pathways of the polluted air masses can be reconstructed by trajectory analysis and elemental tracer techniques (Husain 1986 Rahn and Lowenthal 1985 Chen and Duce 1983 Lowenthal and Rahn 1985). 

With the use of a seven-element tracer system, Lowenthal and Rahn (1985) came to the conclusion that roughly 70% of the tracer elements observed in Alaska came from the former Soviet Union, 25% from Europe, and the remainder from North America. Support for the tracer sets used for Central Europe has been found by Borbely-Kiss etal. (1988). 

Rahn KA and Lowenthal DH (1984) Elemental tracers of distant regiorud pollution aerosols. Science 223 132-139. 

Mobile elements tracers for water mixing and transport... 

Panicle-reactive elements tracers for particle transport ... 

This sensitivity has led to AS use for the detection and identification of minor elements in samples of glass and to the confirmation or exclusion of tracer elements. Tracer elements are added to materials such as polymers, pigments, or glasses and serve as atomic trade marks for a specific manufacturer s product. Tracers are typically low concentrations of rare earth elements. These tests can be essential in helping forensic scientists discriminate otherwise similar materials in product based lawsuits where a manufacturer claims that he or she did not make the product in question. A few basic techniques of AS are in use and each can have a few variations. 

Rahn, K., Lowenthal, D. H., Lewis, N. F. 1982. Elemental tracers and source areas of pollution aerosol in Narragansett, Rhode Island. Tech. Rep. Grad. School Oceanography. Kingston, RI Univ. of Rhode Island. 119 pp. 

Also Mohnen, V. 1983. Letter to the Editor. The New York Times. July 29. is Lugar, R. 1983. To combat acid rain. The New York Times. Aug. 15. i53Rahn K. 1981. Elemental tracers and sources of atmospheric acidity for the Northeast. A statement of new evidence. Nov. 23. Letter distributed to members of Congress by K. Rahn, School of Oceanography, University of Rhode Island. Narragansett, RI. 

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