INVESTIGADORES
SANCHEZ Hector Jorge
congresos y reuniones científicas
Título:
Currently Research Activities in Environmental and Surface Science using Micro-XRF and Grazing-Exit XRF Spectroscopy at the XRF Beamline of the LNLS
Autor/es:
C. A. PÉREZ; HECTOR JORGE SANCHEZ; R.D. PÉREZ; M. RUBIO
Lugar:
París (Francia)
Reunión:
Conferencia; EXRS 2006; 2006
Resumen:
Micro X-ray fluorescence analysis using synchrotron radiation has proved to be a very
powerful analytical technique for trace elements detection in microscopically small areas. The
intrinsic characteristics of the synchrotron radiation (high intensity, polarization and natural
collimation) make possible to improve the sensitivities in comparison with the use of
conventional sources [1]. Micro-pixels mapping of X-ray fluorescence intensities or
concentrations in many variety of samples can be fast completed without intricate
experimental set-up.
Some selected research activities carried out at the x-ray microprobe station of the XRF
beamline of the LNLS [2], as well as a recently developed instrumentation that combine x-ray
microbeam excitation and x-ray fluorescence detection at small take-off angles (grazing-exit
geometry), will be shown in this work.
One research activity will be focused on the evaluation of environmental pollution sources by
the micro-XRF analysis of different individual particles collected from coarse air suspended
particle material.
Another subject of this work will pretend to show some results from the study of the 2D
spatial distribution of arsenic in different rats tissues after exposure to inorganic arsenic. This
subject is as part of a more general research being performed to develop reliable animals
models of hydroarsenicism, which is related to several internal cancers in human being that
had exposed to arsenic by naturally contaminated drinking water.
Finally, preliminary results obtained from the measurements of specially prepared stepped
multilayer samples, using the combination of x-ray microbeam excitation and grazing-exit xray
fluorescence detection will be given. This must be considered as the first steps toward
using this set-up to develop experiments in which the reconstruction of 3D elemental
distributions in thin samples is required.