Evaluation of energy-dispersive x-ray spectra of low-Zelements from electron-probe microanalysis of individual particles

2001 ◽  
Vol 30 (6) ◽  
pp. 419-426 ◽  
Author(s):  
J. Osán ◽  
J. de Hoog ◽  
P. Van Espen ◽  
I. Szalóki ◽  
C.-U. Ro ◽  
...  
Keyword(s):  
Electron Probe Microanalysis ◽  
Electron Probe ◽  
Energy Dispersive ◽  
X Ray ◽  
Individual Particles

Celebrating 40 years of energy dispersive X-ray spectrometry in electron probe microanalysis (EPMA)

2008 ◽  
Vol 14 (S2) ◽  
pp. 1152-1153
Author(s):  
K Keil ◽  
R Fitzgerald ◽  
KFJ Heinrich
Keyword(s):  
New Mexico ◽  
Electron Probe Microanalysis ◽  
Electron Probe ◽  
Energy Dispersive ◽  
X Ray

Extended abstract of a paper presented at Microscopy and Microanalysis 2008 in Albuquerque, New Mexico, USA, August 3 – August 7, 2008

Using Quantitative Iteration to Correct for Pathological Spectral Interferences

1998 ◽  
Vol 4 (S2) ◽  
pp. 222-223
Author(s):  
John J. Donovan
Keyword(s):  
Transition Metal ◽  
Electron Probe Microanalysis ◽  
Interference Effect ◽  
Electron Probe ◽  
The Self ◽  
Energy Dispersive ◽  
Spectral Interferences ◽  
X Ray ◽  
To Come ◽  
Secondary Fluorescence

A number of problematic analytical situations are known to exist in electron probe microanalysis (EPMA) where characteristic x-ray spectral overlaps are not only severe, but are also of the “self-interfering” or “cascade” variety. The “self-interfering” variety is exemplified by the innocuous Ba Lα ↔ Ti Kα; to the fearsome Pb Lα↔As Kα binaries, while “cascade” interferences are often seen among the transition metal series as in Ti Kβ → V Kα - V Kα Cr Kα or as seen with a secondary fluorescence interference effect as in Ni K ⇒ Fe Kα - Fe Kβ → Co Kα. Unlike simple interferences of the type Mn Kβ → Fe Kα, both of these types of spectral interferences are often quite troublesome for the analyst to correct for, especially for Si(Li) and Ge energy dispersive spectrometers (EDS) where the analytical peaks are often so overlapped as to prevent graphical deconvolution, and even for the higher resolution wavelength dispersive spectrometers (WDS) along with the yet to come bolometric energy dispersive detectors (based on projected resolution), the task can still be formidable.

Celebrating 40 Years of Energy Dispersive X-Ray Spectrometry in Electron Probe Microanalysis: A Historic and Nostalgic Look Back into the Beginnings

2009 ◽  
Vol 15 (6) ◽  
pp. 476-483 ◽  
Author(s):  
Klaus Keil ◽  
Ray Fitzgerald ◽  
Kurt F.J. Heinrich
Keyword(s):  
Electron Microscopy ◽  
Solid State ◽  
Electron Probe Microanalysis ◽  
Electron Probe ◽  
Energy Dispersive Spectrometer ◽  
Fluorescence Analysis ◽  
Energy Dispersive ◽  
X Rays ◽  
New Era ◽  
X Ray

AbstractOn February 2, 1968, R. Fitzgerald, K. Keil, and K.F.J. Heinrich published a seminal paper in Science (159, 528–530) in which they described a solid-state Si(Li) energy dispersive spectrometer (EDS) for electron probe microanalysis (EPMA) with, initially, a resolution of 600 eV. This resolution was much improved over previous attempts to use either gas-filled proportional counters or solid-state devices for EDS to detect X-rays and was sufficient, for the first time, to make EDS a practically useful technique. It ushered in a new era not only in EPMA, but also in scanning electron microscopy, analytical transmission electron microscopy, X-ray fluorescence analysis, and X-ray diffraction. EDS offers many advantages over wavelength-dispersive crystal spectrometers, e.g., it has no moving parts, covers the entire X-ray energy range of interest to EPMA, there is no defocusing over relatively large distances across the sample, and, of particular interest to those who analyze complex minerals consisting of many elements, all X-ray lines are detected quickly and simultaneously.

Quantitative energy-dispersive electron probe X-ray microanalysis of individual particles

2006 ◽  
Vol 21 (2) ◽  
pp. 140-144 ◽  
Author(s):  
Chul-Un Ro
Keyword(s):  
Quantitative Determination ◽  
Electron Probe ◽  
Loess Soil ◽  
Energy Dispersive ◽  
Particle Analysis ◽  
Chemical Compositions ◽  
Carbonaceous Particles ◽  
X Ray ◽  
Individual Particles

An electron probe X-ray microanalysis (EPMA) technique using an energy-dispersive X-ray detector with an ultrathin window, designated low-Z particle EPM, has been developed. The low-Z particle EPMA allows the quantitative determination of concentrations of low-Z elements, such as C, N, and O, as well as higher-Z elements that can be analyzed by conventional energy-dispersive EPMA. The quantitative determination of low-Z elements (using full Monte Carlo simulations, from the electron impact to the X-ray detection) in individual environmental particles has improved the applicability of single-particle analysis, especially in atmospheric environmental aerosol research; many environmentally important atmospheric particles, e.g. sulfates, nitrates, ammonium, and carbonaceous particles, contain low-Z elements. The low-Z particle EPMA was applied to characterize loess soil particle samples of which the chemical compositions are well defined by the use of various bulk analytical methods. Chemical compositions of the loess samples obtained from the low-Z particle EPMA turn out to be close to those from bulk analyses. In addition, it is demonstrated that the technique can also be used to assess the heterogeneity of individual particles.

Increase in the intracellular concentration of Na and CI as hepatocytes transform from the normal to the neoplastic state: an electron probe microanalysis study

1978 ◽  
Vol 36 (2) ◽  
pp. 120-121
Author(s):  
Ivan L. Cameron ◽  
Nancy R. Smith ◽  
Thomas B. Pool
Keyword(s):  
Cell Proliferation ◽  
Electron Probe Microanalysis ◽  
Electron Probe ◽  
Intracellular Concentration ◽  
Energy Dispersive ◽  
Scanning Microscope ◽  
X Ray ◽  
Detector Distance ◽  
Intracellular Concentrations ◽  
Working Distance

We have tested the hypothesis that the intracellular concentrations of various elements are involved in control of cell proliferation. Electron probe microanalysis using energy dispersive X-ray spectroscopy was used to test this hypothesis.Briefly, unfixed tissues were rapidly frozen in liquified propane, then sectioned at 4ym and cryosorbed. Ribbons of dry sections were transferred to a polished carbon planchet with a 2mm hole drilled in the center and the sections to be analyzed were suspended over the hole. The tissues were electron probed in a scanning microscope. Suspending the tissue over the hole eliminated continuum counts due to substrate and allowed measurement of Na and Mg. The standard conditions during analysis were: accelerating voltage = 15 KV, count time = 100 sec, working distance = 39 mm, detector distance = 1.5 cm, raster size = 1.5 or 2 cm2 (selected area mode), magnification = 8000X, specimen current = 1.0-1.5 x 10-10 amps.

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