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C. Streli, G. Pepponi, P. Wobrauschek, C. Jokubonis, G. Falkenberg, G. Zaray, J.A. Broekaert, U. Fittschen, B.U. Peschel:
"Recent results of synchrotron radiation induced total reflection fluorescence analysis at HASYLAB, beamline L";
Spectrochimica Acta Part B, 61 (2006), 1129 - 1134.

At the Hamburger Synchrotronstrahlungslabor (HASYLAB), Beamline L, a vacuum chamber for synchrotron radiation-induced total reflection
X-ray fluorescence analysis, is now available which can easily be installed using the adjustment components for microanalysis present at this
beamline. The detector is now in the final version of a Vortex silicon drift detector with 50-mm2 active area from Radiant Detector Technologies.
With the Ni/C multilayer monochromator set to 17 keV extrapolated detection limits of 8 fg were obtained using the 50-mm2 silicon drift detector
with 1000 s live time on a sample containing 100 pg of Ni.
Various applications are presented, especially of samples which are available in very small amounts: As synchrotron radiation-induced total
reflection X-ray fluorescence analysis is much more sensitive than tube-excited total reflection X-ray fluorescence analysis, the sampling time of
aerosol samples can be diminished, resulting in a more precise time resolution of atmospheric events. Aerosols, directly sampled on Si reflectors in
an impactor were investigated. A further application was the determination of contamination elements in a slurry of high-purity Al2O3. No
digestion is required; the sample is pipetted and dried before analysis. A comparison with laboratory total reflection X-ray fluorescence analysis
showed the higher sensitivity of synchrotron radiation-induced total reflection X-ray fluorescence analysis, more contamination elements could be
detected. Using the Si-111 crystal monochromator also available at beamline L, XANES measurements to determine the chemical state were
performed. This is only possible with lower sensitivity as the flux transmitted by the crystal monochromator is about a factor of 100 lower than
that transmitted by the multilayer monochromator. Preliminary results of X-ray absorption near-edge structure measurements for As in xylem sap
from cucumber plants fed with As(III) and As(V) are reported. Detection limits of 170 ng/l of As in xylem sap were achieved.
© 2006 Elsevier B.V. All rights reserved.

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