Chemical speciation in laser-desorption and impact-induced vapor in minerals

Statistics – Applications

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

1630 Impact Phenomena, 3672 Planetary Mineralogy And Petrology (5410), 5420 Impact Phenomena (Includes Cratering)

Scientific paper

Knowledge of the chemical species in vapors produced by hypervelocity impact on spacecraft impact detectors as well as planetary surfaces have applications ranging from determination of the composition of cosmic dust to the effects on atmospheres and climates of large impactors. Direct study of resulting atomic, molecular and ionic species is best accomplished via mass spectrometry. Pulsed laser desorption can be used to approximate small impacts on solid surfaces. We conducted pulsed laser desorption-ionization experiments using two different instruments: (1) a Caltech-built Time-of-Flight Mass Spectrometer (TOFMS) similar to that on board the Cassini spacecraft and (2) a commercial Matrix Assisted Laser Desorption Ionization TOFMS made by Applied Biosystems (Model, Voyager-DE Pro). Minerals included in this study were calcite, dolomite, gypsum, anhydrite, olivine, kamacite, brucite, serpentine, and pyrrhotite. We collected only positive ions. A nitrogen laser (337 nm wavelength, 4 μsec pulse width, and 300 mJ) with power density ranging from 1.0x107 to 1.3x109 W/cm2 induced vaporization and ionization. The results can be summarized as: (1) from kamacite and pyrrhotite, only 54Fe+, 56Fe+, 57Fe+ (both kamacite and pyrrhotite) and 58Ni+, 60Ni+ (kamacite only) as well as contamination ions such as 23Na+ and 39K+, 41K+were observed; (2) Ca-containing minerals (calcite, dolomite, gypsum and anhydrite) produced vapors containing 40Ca+ ions, and, at higher laser power, both 40Ca+ as well as CaO+ ions; (3) Mg-containing minerals (dolomite, olivine, brucite and serpentine) produced vapors containing MgO+ ion; (4) for all hydrous minerals, neither H+ nor H3O+ were observed in the vapor; (5) in the vapors of silicate minerals (olivine and serpentine), SiO+ was observed only from serpentine but not from olivine.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Chemical speciation in laser-desorption and impact-induced vapor in minerals 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 Chemical speciation in laser-desorption and impact-induced vapor in minerals, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Chemical speciation in laser-desorption and impact-induced vapor in minerals will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1892044

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.