Back-scattering electron imaging

Figure 4 is a back-scattered electron image of the sintered platinum-doped tungsten oxide photocat yst (the bri t spheres are platinum). Analysis of the sintered platinum-doped tungsten oxide by ESCA reveal that the platinum the surface is Pt. ... 

Fig. 2. Back-scattered electron image of a euhedral, zoned sulfarsenide hosted in pentlandite (Pn). Inner core (white) is irarsite (IrAsS), outer core (pale grey) is hollingworthite (RhAsS), rim (dark grey) is Rh-bearing Ni-cobaltite.

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.

To enable detection of fine mineral particles (<20pm),back-scattered electron imaging was used. Once the minerals were detected, EDS was used for analysis. Selected lignite particles were scanned to determine the distribution of minerals. Mineral types were then differentiated by variation in back scatter intensity and identified using EDS. The relative proportions (major, minor) and size and spatial distributions of the minerals were recorded. The overall surface of the polished section was viewed and massive minerals were analyzed and their distribution and size recorded. 

Fig. 2. Back scattered electron images of glass-ceramics containing various amounts of MSWI bottom ash ...

Figure 5. Bast fiber from Etowah Mound 1145 core (ca. A.D. 1200). Back-scattered electron image magnification 345 x.

Figure 13 A cluster of syngenetic pyrite framboids in a bituminous coal. Micrometer-sized bright grains dispersed in the cluster are crystals of clausthalite (PbSe). Scanning Electron photomicrograph, back-scattered electron image (scale bar = 10 p,m).

Several plagioclasc grains from annealed samples as well as shock-loaded run products were embedded in epoxy resin and polished. Observation was performed with an optical microscope using reflected and transmitted light Major and minor element compositions were determined by an electron probe microanalyzer. Shock textures were also examined in detail with a scanning electron microscope using back-scattered electron images. 

Figure 8.11 Rock varnish interlayers with iron film and silica glaze at Whoopup Canyon, Wyoming. (A) Iron film (back-scatter electron image) acts as a case-hardening agent, and rock varnish accretes on top of the iron film exposed by petroglyph manufacturing. (B) Varnish actively assists in case hardening (back-scatter electron image) when the leached cations reprecipitate with silica glaze in sandstone pores.

Analysis of Ca, Mg, Fe, Mn and Sr in calcite, ankerite and siderite was performed on a JEOL 733 electron microprobe. Accelerating voltage was 15 kV sample current was 12 nA, stabilized on brass. Spot size was 10 pm. Counting time for all elements was 20 s, except for Sr, which was analysed for 60s. Detection limits are approximately 340 ppm for Mg, 450 ppm for Fe, 310 ppm for Mn and 185 ppm for Sr. Totals between 97 and 103% were accepted. Standards were carbonate minerals (calcite for Ca dolomite for Ca, Mg siderite for Fe, Mn and coral for Sr) in the standard collection at the University of Texas electron microprobe laboratory. Beam placement was guided by back-scattered electron imaging. Si was routinely counted by WDS to check for possible contamination from... 

Rg. 2. Thin-section scale localization of authigenic si derite. Back-scattered electron images. Scale bars 10 Jim. (A) Zoned siderite (bright mineral) localized around and within a detrital chlorite (KY218B). (B) Siderite (s) localized on partially dissolved and kaolinized K-feldspar (f). 

Fig. 3. Pre-quartz, early calcite. Back-scattered electron images. Scale bars 100 pm. (A) Early calcite (c) that postdates early siderite (bright rhombs) KY64A.

Fig. 4. Post-quartz late calcite (c) localized on K-feldspar remnants (k). Arrow indicates euhedral terminations of quartz overgrowths. Back-scattered electron image. Scale bar lOOftm.

Most of the dolomites (including the detrital cores) have calcium-enriched compositions (Table 6 Fig. 8). Zoning within the ferroan dolomite is clearly visible in back-scattered electron images, and the higher Fe contents tend to be characteristic of the later zones (Fig. 7A). The degree of Ca enrichment, however, is not strongly controlled by Fe content and more Fe-rich portions of the crystals display a range in Ca content that is nearly as broad as that of less Fe-rich portions. Mn content is correlated positively with Fe enrichment (Fig. 9). 

Fig. 4. Localization of authigenic calcite (c) on dissolving silicate grains. Back-scattered electron images. (A) Calcite replaces parts of two K-feldspar grains (K) from the M. Cervarola Formation. (B) Partial calcitization of an epidote grain (e) in the Borello Formation.

Volumetrically minor authigenic ferroan dolomite is present locally as overgrowths on distinctive cores of partially dissolved detrital dolomite (Fig. 5). Prominent zoning of Fe and Mg in these overgrowths is readily observed on back-scattered electron images. Dolomite precipitation clearly precedes the formation of calcite cement. 

Fig. 5. Authigenic ferroan dolomite overgrowth (o) on a core of fractured detrital dolomite (d) from the Bismantova Formation. Overgrowth development preceded precipitation of calcite cement. Similar dolomite overgrowths are observed in the Borello Formation. Back-scattered electron image.

Fig. 6. Pressure dissolution ofForaminifera. Dark grey grains are quartz. Calcite cements the grains and also fills the intraskeletal pores. Back-scattered electron images. (A) Bismantova Formation. Large grain in lower right is a mica. (B) Borello Formation.

Application of quantitative back-scattered electron image analysis in isotope interpretation of siderite cement ... 

In back-scattered electron image (BEI, SEM investigation) these phases, as in work [2], have the following contrast /-phase (Al63Cu25Fe12) looks gray, (3-... 

Microscopy, Atomic force (AFM) 191, 193, 316, 429, 572, 1192, 1194, 1373 Microscopy, back-scattered electron image 547, 556 Microscopy, confocal 548... 

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