EPMA images

Wolkenstein M, Hutter H, Nikolov SG, Schnitz I, Grasserbauer M (1997b) Comparison of wavelet filtering with well-known techniques for EPMA image de-noising. J Trace Microprobe Techn 15 33... 

There are several problems encountered in combination of SIMS and EPMA images. Due to the change of the sample holder, the images sometimes have different orientations. SIMS and EPMA have different projection functions, i.e. the projection of different concentrations to the resulting image intensity values is non-monotonic and non-linear. EPMA and SIMS micrographs also exhibit various artefacts, e.g. lateral distortion of the SIMS distributions [26]. Most of these distortions are both local and non-linear. All the above... 

Registration of SIMS and EPMA images based on their wavelet transform maxima... 

Fig. 31 Chromium distribution obtained with EPMA and SIMS in a soldering layer system consisting of chromium solder (Ni-Fe-Cr-Si-B)jsteel the EPMA image E(x,y) (left), size 256 x 256 pixels the SIMS image S(x,y)(right), size 256 x 256 pixels.

Fig. 35 A2jl[x,y) > T2/ y=2i thresholded wavelet gradient maxima at scales 2 and 2 of the images in Fig. 31. The first and second columns display the thresholded multiscale edges of the EPMA and SIMS micrographs. The scale increases from top to bottom. Black pixels correspond to wavelet maxima points. The corresponding thresholds at scale 2 and 2 are X22 = 12 and X21 = 3.5 for the EPMA image, and X21 = 5 and X2S = 2 for the SIMS...

Fig. 36 The registered (matched) EPMA and SIMS images of the Cr distribution in Fig. 31 A2iE x,y) > i.5 - the thresholded wavelet gradient maxima of the EPMA image at scale 2 (top left) ) > 2 - the thresholded wavelet gradient maxima of the...

SIMS image at scale 2 (top right) the EPMA image E(x,y) (middle left) the SIMS image S(x,y) (middle right) the corrected (transformed) EPMA image E x,y) (bottom right). The dark crosses mark the positions of the control points q. In this case... 

M. Wolkenstein, M. Mutter, S.G. Nikolov, I. Schmitz and M. Grasserbauer, Comparison of Wavelet Filtering with Established Techniques for EPMA Image De-Noising, J. Trace and Microprobe Techniques, 15 (1) (1997), 33 9. 

S.D. Boehmig, B.M. Reichl, H. Stoeri and H. Mutter, Automatic Matching of SAM, SIMS and EPMA Images, Fresenius J. Analytical Chemistry. 349, (1993). 

Figure 2 The EPMA image of polished and thermally etched surface of the LNT ceramic sintered at...

Fig. 7.2 Electron probe micro-analyzta- (EPMA) images of the EnYAG ceramics a b 90 %. Reproduced with permission from [22]. Copyright 2011, Elsevier...

Electron Probe Microanalysis, EPMA, as performed in an electron microprobe combines EDS and WDX to give quantitative compositional analysis in the reflection mode from solid surfaces together with the morphological imaging of SEM. The spatial resolution is restricted by the interaction volume below the surface, varying from about 0.2 pm to 5 pm. Flat samples are needed for the best quantitative accuracy. Compositional mapping over a 100 x 100 micron area can be done in 15 minutes for major components Z> 11), several hours for minor components, and about 10 hours for trace elements. 

The electron-optical performance of the EPMA system is indistinguishable from that of a conventional scanning electron microscope (SEM) thus, EPMA combines all of the imaging capabilities of a SEM with quantitative elemental analysis using both energy- and wavelength-dispersive X-ray spectrometry. ... 

In electron-optical instruments, e.g. the scanning electron microscope (SEM), the electron-probe microanalyzer (EPMA), and the transmission electron microscope there is always a wealth of signals, caused by the interaction between the primary electrons and the target, which can be used for materials characterization via imaging, diffraction, and chemical analysis. The different interaction processes for an electron-transparent crystalline specimen inside a TEM are sketched in Eig. 2.31. 

Fig. 3.24. Di rect-imaging mode SIMS image of a passivation layer on a niobium alloy [3.54], Boron enrichment at the interface is not visible with EPMA. Measurement time 10 s image diameter 150 pm primary ions OJ primary energy 5.5 keV.

EPMA Solid Wide (Z > 4) Surface, imaging, micro-analysis 3... 

Fig. 8.26. Segregation of copper in an iron copper soak alloy MI metallographic image, AE absorbed electrons measured by EPMA, and four element-specific X-ray scanning images by EPMA, below three elemental-specific relief plots by SIMS according to Ehrlich et al. [1979]... 

Four samples were similarly selected for the EPMA experiments. The samples were dried and embedded in polished epoxy cylindrical plugs. Backscattered electron (BSE) images as well as elemental maps of As, Fe and Ni (EDS/WDS) were collected using a JEOL 8600 Superprobe electron microprobe analyzer (Dept, of Geological Sciences, University of Saskatchewan). 

Fig. 2. SEM-BSE image and EPMA maps from Esfordi deposit, a) White crystals in fractures are REE minerals, b). RE minerals (sketched by black colour) are interstitial to actinolite (gray parts), c) RE minerals (black) and apatite (white) EPMA map.

Fig. 2. EPMA back-scattered electron images of a polished section from Chelehkureh deposit, a) carbonate in a mineralized vein with chalcopyrite b) larger image of carbonate grain marked by + in previous image, c), d) and e) are in turn compositional Mg, Fe and Ca images of that grain.

Photon Vis light imaging microspectroscopy, mi-crospectrolluorimetry, LIBS, Raman and FTIR SEM-EDX, EPMA ... 

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