Statistics – Applications
Scientific paper
Nov 2009
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2009m%26ps...44.1627b&link_type=abstract
Meteoritics & Planetary Science, vol. 44, Issue 10, p.1627-1642
Statistics
Applications
2
Comet(S) Chemical Composition, Element Mapping, Gems, Electron Microscopy
Scientific paper
Electron-beam studies of extraterrestrial materials with significantly improved spatial resolution, energy resolution, and sensitivity are enabled using a 300 keV SuperSTEM scanning transmission electron microscope(STEM) with a monochromator and two spherical aberration correctors. The improved technical capabilities enable analyses previously not possible. Mineral structures can be directly imaged and analyzed with single-atomic-column resolution, liquids, and implanted gases can be detected, and UV-VIS optical properties can be measured. Detection limits for minor/trace elements in thin (<100 nm thick) specimens are improved such that quantitative measurements of some extend to the sub-500 ppm level. Electron energy-loss spectroscopy (EELS) can be carried out with 0.10-0.20 eV energy resolution and atomic-scale spatial resolution such that variations in oxidation state from one atomic column to another can be detected. Petrographic mapping is extended down to the atomic scale using energy dispersive X-ray spectroscopy (EDS) and energy-filtered transmission electron microscopy (EFTEM) imaging. Technical capabilities and examples of the applications of SuperSTEM to extraterrestrial materials are presented, including the UV spectral properties and organic carbon K-edge fine structure of carbonaceous matter in interplanetary dust particles (IDPs), X-ray elemental maps showing the nanometer-scale distribution of carbon within GEMS (glass with embedded metal and sulfides), the first detection and quantification of trace Ti in GEMS using EDS, and detection of molecular H2O in vesicles and implanted H2 and He in irradiated mineral and glass grains.
Bradley John P.
Dai Zu Rong
No associations
LandOfFree
Analytical SuperSTEM for extraterrestrial materials research does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Analytical SuperSTEM for extraterrestrial materials research, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Analytical SuperSTEM for extraterrestrial materials research will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1704703