Electron Probe Wavelength Dispersive Spectroscopy (WDS)

By LonelY TravelleR -

Electron-probe X-ray fluorescence (EP-XRF) analysis has been widely used in scanning electron microscopy instrumentation for elemental analysis of specimens. In the SEM, the surface of a solid sample is excited with a highly-focused energetic beam of electrons, which induces X-ray fluorescence from the elements within the sample.

Polycapillary collimating optics can be used to direct emitted X-ray fluorescence as a parallel beam from the small electron excitation area to a flat crystal monochrometer to increase the diffracted beam intensity and therefore greatly increase the elemental discrimination and detection sensitivity.
Electron probe wavelength dispersive spectroscopy

Comments

Post a Comment

Popular posts from this blog

Luminal contrast and distension CT enterography

By LonelY TravelleR -
Image
Neutral or low-density oral contrast media are a prerequisite for good-quality CT enterography [3-5] because they maximise contrast between the lumen and enhancing small bowel wall, facilitating assessment of mucosal thickening and wall stratification/enhancement patterns [1-8]. Water–methylcellulose solution, polyethylene glycol, commercially available low-density barium, 0.1% Volumen (Bracco, Milan, Italy) and milk are examples of neutral oral contrast agents with CT attenuation properties similar to that of water. Water alone usually results in inadequate distension due to rapid reabsorption, although some authors advocate its use [9]. Use of Volumen has been shown to improve the quality of bowel distension compared with water alone [4,10-12], but it remains unlicensed for use in the UK and therefore is not available. Milk was shown to give similar results as Volumen [13], but although less expensive and freely available in Europe, it may be deemed unpalatable by many patients wh...
Read more