Geologic materials

Figure 4.9. Shock pressure versus particle velocity for engineering materials, geological material, and explosive detonation products. Intersection of detonation product curves with nonreactive media predicts shock pressure and particle velocity at an explosive sample interface. (After Jones (1972).)...

While the structure/property behavior of numerous shock-recovered metals and alloys has received considerable attention in the literature to date, the response of ceramics, cermets, and other brittle solids (including geological materials) to shock loading remains poorly understood [9], The majority of shock-recovery studies on brittle materials have concentrated on examining... 

Schuster, S.H. and Isenberg, J., Equations of State for Geologic Materials, US Defense Nuclear Agency Report No. DNA 2925Z, Washington, DC, 46 pp., September 1972. 

Whitman, L., and Wright, J.P., Tensile Behavior of Geological Material in Ground Shock Calculations, Weidlinger Associates Technical Report for Contract No. DNA001-75-C-0076, New York, 42 pp., June 1975. 

SIMS is one of the most powerful surface and microanalytical techniques for materials characterization. It is primarily used in the analysis of semiconductors, as well as for metallurgical, and geological materials. The advent of a growing number of standards for SIMS has gready enhanced the quantitative accuracy and reliability of the technique in these areas. Future development is expected in the area of small spot analysis, implementation of post-sputtering ionization to SIMS (see the articles on SALI and SNMS), and newer areas of application, such as ceramics, polymers, and biological and pharmaceutical materials. 

The Table shows a great spread in Kd-values even at the same location. This is due to the fact that the environmental conditions influence the partition of plutonium species between different valency states and complexes. For the different actinides, it is found that the Kd-values under otherwise identical conditions (e.g. for the uptake of plutonium on geologic materials or in organisms) decrease in the order Pu>Am>U>Np (15). Because neptunium is usually pentavalent, uranium hexavalent and americium trivalent, while plutonium in natural systems is mainly tetravalent, it is clear from the actinide homologue properties that the oxidation state of plutonium will affect the observed Kd-value. The oxidation state of plutonium depends on the redox potential (Eh-value) of the ground water and its content of oxidants or reductants. It is also found that natural ligands like C032- and fulvic acids, which complex plutonium (see next section), also influence the Kd-value. 

Johnston, H.M. Gillham, R.W. "A Review of Selected Radionuclide Distribution Coefficients of Geologic Materials" TR-90 Atomic Energy of Canada Ltd Univ. of Waterloo, 1980. 

Trace Element Analysis of Geological Materials. By Roger D. Reeves and Robert R. Brooks... 

Lightfoot pc (1993) The Interpretation of Geoanalytical data in analysis of geological materials. In Riddle C, ed. Analysis of Geological Materials, pp 377-455. Marcel Dekker, Inc. New York. 

Taggart JE Jr, Lindsay JR, Scott BA, Vivit DV, Bartel AJ, Stewart K C (1993) Analysis of geological materials by wavelength-dispersive X-ray fluorescence spectrometry. In Badecker PA, ed. U.S. Geological Survey Bulletin 1770. Methods for Geochemical Analysis, pp E1-E19. 

Raptis K, Mayer K, Hendrickx F, De Bievre P (1998) Preparation and certification of new thorium isotopic reference materials. Fresenius J Anal Chem 361 400-403 Rehkamper M, Halliday AN (1999) The precise measurement of T1 isotopic compositions by MC-ICP-MS Application to the analysis of geological materials and meteorites. Geochim Cosmochim Acta 63 935-944... 

Sen Gupta JG, Bertrand NB (1995) Direct ICP-MS determination of trace and ultratrace elements in geological materials after decomposition in a microwave oven I. Quantitation of Y, Th, U, and the lanthanides. Talanta 42 1595-1607... 

Turner S, van Calsteren P, Vigier N, Thomas L (2001) Determination of thorium and uranium isotope ratios in low concentration geological materials using a fixed multi-collector-lCP-MS. J Anal At Spectrom 16 612-615... 

Were all of these newly discovered substances also new elements This question would not be answered for some years but there was a flurry of other major discoveries to keep the protagonists occupied. Pierre Curie discovered that radioactivity released large quantities of heat (Curie and Laborde 1903) which appeared mysterious—as if the heat was coming from nowhere. This discovery provided an extra heat source for the Earth and reconciled the estimates of a very old Earth, based on geological estimates, with the young age calculated by Lord Kelvin from cooling rates. The year 1903 also witnessed the first demonstration that a-decay released He (Ramsay and Soddy 1903). The build up of He was soon put to use to date geological materials, initially by Rutherford in 1905 who calculated the first ever radiometric age of 500 Myr for a pitchblende sample, and then by Strutt who examined a wide variety of minerals (Strutt... 

Vol. 51 Trace Element Analysis of Geological Materials. By Roger D. Reeves and Robert R. Brooks Vol. 52 Chemical Analysis by Microwave Rotational Spectroscopy. By Ravi Varma and Lawrence... 

In connection with our field measurements, samples of geological materials were collected for analyses in the laboratory. Activity concentrations were measured by standard gamma spectrocqpy with a 90-cm3 Ge (Li) detector and a Canberra Model 8100 multichannel analyser. Details on calibration and procedure were published earlier (Stranden, 1985). Rn-222 exhalation measurements were also performed... 

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