For the FIB thin section samples utilizing STXM. Figure 3a,b
For the FIB thin section samples utilizing STXM. Figure 3a,b show a scanning ion microscope (SIM) image on the FIB thin section on the ferrous saponite particle. The broken squares in Figure 3a show the regions analyzed with STXM. The front view on the section shows an apparently ARN-6039 Autophagy uniform structure of your sample (Figure 3a). The bottom view of your section shows the uniform thickness for the analyzed location in between the molybdenum grid as well as the pillar structure (Figure 3b). Figure 3c show the results of mapping of optical density at single X-ray energies. Panels (c) and (d) of Figure three represent the outcomes before air exposure, whereas the panels (e) and (f) are these after air exposure for just about the same region of panels (c) and (d) (see panel (a) for the analyzed location). The difference in the optical density at an X-ray energy of 708.six eV (Figure 3d,f) to 705.0 eV (Figure 3c,e) represented the distinction in degree of absorption by iron within the samples. A comparison of Figure 3c,d Buclizine custom synthesis indicated there was a distinction in optical density resulting from the presence of iron within the top-right component in the analyzed location (hereafter, we’ll refer to this as the Fe-rich region). The region with low optical density in Figure 3c,d shows low levels of absorption on account of iron (hereafter, we’ll refer to this location because the Fe-depleted area). A comparison of Figure 3e,f also showed that the distribution of Fe-rich/depleted location immediately after air exposure agreed with that observed just before air exposure (Figure 3c,d; see Section four.two. for the formation mechanism). Each the left-end aspect in Figure 3c and the right-end portion in Figure 3e,f are out with the thinned region with the FIB program (the dotted lines in the panel (b) correspond to those within the panels (c )). The typical XANES spectra on the Fe-rich and Fe-depleted locations are shown in Figure 3g. The XANES spectra showed that no substantial X-ray absorption was featured in the Fe-depleted location, whereas there had been clear absorption characteristics as a consequence of iron inside the Fe-rich area each before and following air exposure. To further investigate the oxidation state of iron (i.e., ferrous vs. ferric) as well as the distribution within the Fe-rich/depleted location, singular value decomposition (SVD) mapping was conducted for both stack pictures (Figure 3h,i). We employed four components (XANES spectra of ferrous saponite, ferric smectite, magnetite, along with the Fe-depleted area) for fitting Hereafter, we use the term ferric smectite for Fe(III)-rich smectite (ferric smectite doesn’t represent nontronite). We displayed the results as a RGB colour map applying relative contributions by ferrous saponite (green), ferric smectite (red), and magnetite (blue). These 3 elements were precisely the same as these applied for fitting the bulk spectra from the ferrous saponite powder just before and soon after air exposure (Figure two). The Fe-rich location was recommended to become composed mainly of ferrous saponite just before air exposure (Figure 3h). However, the spectra after air exposure exhibited mixtures of ferric and ferrous iron inside the Fe-rich location with spatial variation. In specific, the micro-vein-like structures (represented by the red colour (ferric smectite) in Figure 3i) appeared inside the Fe-rich area (Figure 3g), where ferrous saponite was predominant just before air exposure (Figure 3h). These benefits strongly recommended that: (1) ferrous saponite was oxidized by air exposure even inside a short time (i.e.,Minerals 2021, 11,10 ofMinerals 2021, 11, xhalf each day); and that (two) oxidation of ferrous saponite proceeded spatia.
