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The Stable Isotope Laboratory
(Gas Source - Mass Spectrometry) CHEM 0233 is equipped
with two Micromass IsoPrime mass spectrometers, one ThermoFinnigan
Delta Plus mass spectrometer, and a ThermoFinnigan MAT 253 mass
spectrometer. The facilities were obtained with NSF and University of
Maryland funds and are overseen by two PIs (Kaufman and Farquhar). The
instrumentation described below provides innumerable opportunities for
cutting-edge research.
- One Micromass IsoPrime
is dedicated to
dual inlet (DI) measurements, particularly for the automated analysis
of large numbers of carbonate (C, O) and water (O, H) samples to high
analytical accuracy and precision. The system includes an
automated manifold device for the extraction and sequential measurement
of gas samples prepared off-line.
- The other Micromass
Isoprime utilizes
continuous flow (CF) inlet systems coupled with high temperature
combustion or reduction ovens for the automated isotopic analysis of
organic matter (C, N, S, O, H), as well as mineral sulfates (S, O),
sulfides (S), nitrates (N, O), and phosphates (O). Another peripheral
that acts as a head space gas extractor will allow for the automated
analysis of dissolved inorganic carbon (C) in water, as well as a back
up device for additional carbonate and water samples typically run on
the DI system.
- The ThermoFinnigan
Delta Plus is
dedicated to simultaneous analysis of 17O/16O
and 18O/16O using molecular oxygen as the
analyte is presently configured for dual inlet analyses with
capabilities for on-line pyrolysis of nitrate and a dedicated inlet for
laser fluorination using a Synrad CO2 laser.
- The ThermoFinnigan
MAT 253 is dedicated
to simultaneous analysis of 33S/32S, 34S/32S,
and 36S/32S using sulfur hexafluoride as the
analyte and an on-line fluorination manifold that can be used for
Ni-tube fluorinations of silver sulfide, and CO2 laser
fluorination of sulfide minerals. We are presently developing
techniques of in-situ fluorination using a Lambda Physik Compex 110
Excimer laser with KrF fill gas that is coupled to a New Wave beam
delivery system and that will be coupled to a continuous flow interface.
- IR and UV laser
capabilities (two Synrad CO2 lasers and one Lambda Physik
Compex 110 Excimer laser) for in-situ and low blank isotopic analysis
of oxygen and sulfur isotope ratios.
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