Synchrotron x-ray fluorescence microprobe quantitative analysis of heterogeneous samples

Conference · Tue Oct 01 04:00:00 EDT 1996

OSTI ID:370261

Zavarin, M ^[1]

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1. Univ. of California, Berkeley, CA (United States)

With the advent of highly energetic synchrotron x-ray sources and development of multilayer x-ray focusing mirrors, it has become possible to map trace element concentrations at the ppm level, on a micrometer scale, at ambient temperatures and pressures, and with little sample preparation. Quantitative elemental mapping of heterogeneous soil samples requires an accounting of particle size effects. We found that heterogeneity effects become increasingly pronounced as the matrix mass absorption at the fluorescence energy of interest increases. Extremely heterogeneous systems may have order of magnitude differences in trace metal fluorescence intensity, which are solely due to heterogeneity effects. We have also found that the relative fluorescence of trace element K{alpha} and K{beta} lines reflect the heterogeneity of the sample due to the difference in matrix mass absorption at the two fluorescence energies. It may be possible to use this effect to assess the heterogeneity of a sample and possibly reduce the effect of sample heterogeneity on quantitative elemental analysis. The K{alpha}/K{beta} fluorescence variation may also be used to determine thicknesses of layered systems at the 1 to 250 micrometer scale.

• OSTI ID: 370261
• Report Number(s): CONF-960376--
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
FLUORESCENCE
HETEROGENEOUS EFFECTS
METALS
MIRRORS
PARTICLE SIZE
POLLUTANTS
SAMPLE PREPARATION
SOILS
SPATIAL DISTRIBUTION
TRACE AMOUNTS
X-RAY SOURCES