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Biological control over coral skeletal composition is poorly understood but critically important to paleoenvironmental reconstructions. We present microanalytical measurements of trace-element abundances as well as oxygen and carbon isotopic compositions o ...
We recently demonstrated an original approach to highly selective laser isotope separation of carbon-13 that employs vibrational overtone pre-excitation of CF3 H together with infrared multiphoton dissociation [O.V. Boyarkin, M. Kowalczyk, T.R. Rizzo, J. C ...
The flux of charge exchange ( CX) neutrals measured by neutral particle analysers ( NPAs) is the line integral along the viewline of the NPA and contains information about the ion energy distribution of the observed plasma. On the Tokamaka a Configuration ...
We present a 60-year record of the stable isotopes of atmospheric carbon monoxide (CO) from firn air samples collected under the framework of the North Greenland Eemian Ice Drilling (NEEM) project. CO concentration, δ 13C, and δ 18O of CO were measured by ...
A NanoSIMS ion microprobe was used to map the submicron-scale distributions of carbon, nitrogen, sulfur, silicon, and oxygen in organic microfossils and laminae in a thin section of the similar to 0.85 billion year old Bitter Springs Formation of Australia ...
Hydrogen, carbon, nitrogen, and oxygen isotopic compositions are heterogeneous among comet 81P/Wild 2 particle fragments; however, extreme isotopic anomalies are rare, indicating that the comet is not a pristine aggregate of presolar materials. Nonterrestr ...
Ion-microprobe was used to measure Li abundances and isotopic compositions in pyroxenes from three Martian meteorites belonging to the nakhlite family. The profiles performed across augite crystals from Northwest Africa 817 show a large isotopic zoning fro ...
We show how powder samples at natural isotopic abundance can be assigned to crystal structures by using high-resolution proton and carbon-13 solid-state NMR spectra in combination with first principles calculations. Homonuclear proton double-quantum spectr ...
The inability to determine molecular structures from powdered samples is a key barrier to progress in many areas of molecular and materials science. We report an approach to structure determination that combines molecular modeling with experimental spin di ...
Iron isotopes were used to investigate iron transformation processes during an in situ field experiment for removal of dissolved Fe from reduced groundwater. This experiment provided a unique setting for exploring Fe isotope fractionation in a natural syst ...
