A5044778626- Astro and Planetary Science
- Planetary Science and Exploration
- High-pressure geophysics and materials
- Astrophysics and Star Formation Studies
- Geological and Geochemical Analysis
- Spacecraft and Cryogenic Technologies
- Heavy metals in environment
- Coal and Its By-products
- Silicon Effects in Agriculture
- Isotope Analysis in Ecology
- Geochemistry and Elemental Analysis
- Radioactive element chemistry and processing
- Stellar, planetary, and galactic studies
- Extraction and Separation Processes
- Nuclear Physics and Applications
- Advanced ceramic materials synthesis
- Geology and Paleoclimatology Research
- Chemical Thermodynamics and Molecular Structure
- Boron and Carbon Nanomaterials Research
- Paleontology and Stratigraphy of Fossils
- Electron and X-Ray Spectroscopy Techniques
- Mining Techniques and Economics
- Heavy Metal Exposure and Toxicity
- Archaeology and ancient environmental studies
- Mining and Gasification Technologies
Goethe University Frankfurt
2025
University of New Mexico
2018-2024
Virginia Tech
2022-2023
United States Naval Research Laboratory
2020-2023
Nova Research Company (United States)
2020
Planetary Science Institute
2013
University of Tennessee at Knoxville
2013
Abstract Evaporation or freezing of water-rich fluids with dilute concentrations dissolved salts can produce brines, as observed in closed basins on Earth 1 and detected by remote sensing icy bodies the outer Solar System 2,3 . The mineralogical evolution these brines is well understood regard to terrestrial environments 4 , but poorly constrained for extraterrestrial systems owing a lack direct sampling. Here we report occurrence salt minerals samples asteroid (101955) Bennu returned...
Abstract Concentrations of sedimentary molybdenum (Mo) have been used as a proxy for palaeoceanographic redox conditions based on the distinctive behaviour Mo under oxic versus euxinic ( i.e. , anoxic and sulfidic) conditions. However, mechanisms that govern sequestration in various settings are not fully resolved. It has previously proposed sulfate-reducing bacteria (SRB), main drivers regulators conditions, can actively take up reduce intracellularly passively induce Fe-independent...
Abstract We have carried out a systematic study involving SEM , EPMA and TEM analyses to determine the textures compositions of sulfides sulfide–metal assemblages in suite minimally weakly altered CM CR carbonaceous chondrites. attempted constrain distribution origin primary that formed solar nebula, rather than by secondary asteroidal alteration processes. Our focused primarily on sulfide associated with chondrules, but also examined some occurrences within matrices these meteorites....
Abstract The presence of primary iron sulfides that appear to be aqueously altered in CM and CR carbonaceous chondrites provides the potential study effects and, by extension, conditions aqueous alteration. In this work, we have used SEM , TEM EPMA techniques characterize show evidence secondary alteration styles consist pyrrhotite altering pentlandite ( s only), magnetite s), phyllosilicates only) grains initially formed crystallization from immiscible sulfide melts chondrules...
The increase in fires at the wildland–urban interface has raised concerns about potential environmental impact of ash remaining after burning.
Abstract We have analyzed glasses in eight howardites with the aim of distinguishing their origins as impact melts or pyroclasts. Although theoretical calculations predict that pyroclastic eruptions could taken place on Vesta, occurrence HED meteorites has not been documented. This study involved petrographic examination textures, electron microprobe analysis major and minor elements, LA ‐ ICP MS for selected trace elements. Previously documented textural compositional differences between...
Abstract Presolar silicon carbide (SiC) grains in meteoritic samples can help constrain circumstellar condensation processes and conditions C-rich stars core-collapse supernovae (CCSNe). This study presents our findings on eight presolar SiC from asymptotic giant branch (AGB) (four mainstream one Y grain) CCSNe (three X grains), chosen the basis of μ -Raman spectral features that were indicative their having unusual non-3C polytypes and/or high degrees crystal disorder. Analytical...
We have carried out a SEM-EPMA-TEM study to determine the textures and compositions of relict primary iron sulfides their alteration products in suite moderately heavily-altered CM1 carbonaceous chondrites. observed four textural groups altered sulfides: 1) pentlandite+phyllosilicate (2P) grains, characterized by pentlandite with submicron lenses phyllosilicates, 2) pyrrhotite+pentlandite+magnetite (PPM) pyrrhotite-pentlandite exsolution magnetite veining secondary pentlandite, 3)...
The carbon isotope compositions (δ13C values) of 23 hard ciders obtainable in the United States were analyzed to detect adjuncts, specifically added C4 sugars (i.e., corn syrup and cane sugar). In contrast, main ingredient is fruit, mostly apple, juice which derived from C3 plants. labeled ingredients found be inconsistent with ratios. A higher proportion imported studied had no isotopic evidence C4-based sweetener, while most domestic elevated δ13C values, indicative sugar additives....
Abstract We have carried out a SEM‐EPMA‐TEM study to determine the textures and compositions of relict primary iron sulfides their alteration products in suite moderately heavily altered CM1 carbonaceous chondrites. observed four textural groups sulfides: (1) pentlandite+phyllosilicate (2P) grains, characterized by pentlandite with submicron lenses phyllosilicates; (2) pyrrhotite+pentlandite+magnetite (PPM) pyrrhotite–pentlandite exsolution magnetite veining secondary pentlandite; (3)...
Abstract– This work describes two newly discovered eucrite breccias: three presumably paired meteorites, all named Northwest Africa (NWA) 6105, and NWA 6106. For each meteorite, major‐ minor‐element compositions of minerals were determined using the electron microprobe. Pyroxene Fe‐Mn co‐variations bulk‐rock oxygen isotope confirm their classification as eucrites. Variations in mineral textures are attributed to differences clast types present (i.e., basaltic or cumulate eucrite). The...