Results 21 to 30 of about 27,054 (290)

Gold in ash and slag material of the Primorsk hydroelectric power [PDF]

E3S Web of Conferences, 2020
The paper shows the results of studies on the identification of noble-metal mineralization in various components of ash and slag formations: underburning, aluminosilicate microspheres, initial ash (fed to the magnetic separation of the technological ...
Lavrik Natalia, Henning Peter
doaj   +1 more source

X-Ray Spectroscopy of Interstellar Carbon: Evidence for Scattering by Carbon-bearing Material in the Spectrum of 1ES 1553+113

The Astrophysical Journal, 2023
Molecules and particles make up ∼40%–70% of carbon in the interstellar medium, yet the exact chemical structure of these constituents remains unknown. We present carbon K-shell absorption spectroscopy of the Galactic interstellar medium obtained with the
John Staunton, Frits Paerels
doaj   +1 more source

Presolar grains in primitive ungrouped carbonaceous chondrite Northwest Africa 5958 [PDF]

Meteoritics & Planetary Science, 2019
AbstractWe report a correlated NanoSIMS‐transmission electron microscopy study of the ungrouped carbonaceous chondrite Northwest Africa (NWA) 5958. We identified 10 presolar SiC grains, 2 likely presolar graphite grains, and 20 presolar silicate and/or oxide grains in NWA 5958. We suggest a slight modification of the commonly used classification system
Larry R. Nittler, Rhonda M. Stroud, Conel M. O'D. Alexander, Kaitlin Howell   +3 more
openaire   +2 more sources

Did a Complex Carbon Cycle Operate in the Inner Solar System?

Life, 2020
Solids in the interstellar medium consist of an intimate mixture of silicate and carbonaceous grains. Because 99% of silicates in meteorites were reprocessed at high temperatures in the inner regions of the Solar Nebula, we propose that similar levels of
Joseph A. Nuth, Frank T. Ferguson, Hugh G. M. Hill, Natasha M. Johnson   +3 more
doaj   +1 more source

Grain Alignment and Rotational Disruption by Radiative Torques in Exoplanet Atmospheres

The Astrophysical Journal, 2023
Dust clouds are ubiquitous in the atmospheres of hot Jupiters and affect their observable properties. The alignment of dust grains in the clouds and resulting dust polarization provide a promising way to study the magnetic fields of exoplanets. Moreover,
Thiem Hoang, Alex Lazarian
doaj   +1 more source

A multicomponent model of the infrared emission from Comet Halley [PDF]

, 1988
A model based on a mixture of coated silicates and amorphous carbon grains produces a good spectral match to the available Halley data and is consistent with the compositional and morphological information derived from interplanetary dust particle ...
Allamandola, Louis J., Bregman, Jesse D., Sandford, Scott A., Swamy, K. S. Krishna, Witteborn, F. C.   +4 more
core   +2 more sources

Formation of PAHs and Carbonaceous Solids in Gas-Phase Condensation Experiments [PDF]

, 2009
Carbonaceous grains represent a major component of cosmic dust. In order to understand their formation pathways, they have been prepared in the laboratory by gas-phase condensation reactions such as laser pyrolysis and laser ablation.
Allain, Baum, Boulanger, C. Jäger, Cao, Cherchneff, Cherchneff, Clayton, Draine, Drilling, F. Huisken, Foing, H. Mutschke, Hrivnak, I. Llamas Jansa, Jäger, Jäger, Jäger, Kwok, Kwok, Lederer, Lodders, Monier, Nuccitelli, Schnaiter, Sellgren, Th. Henning, Vijh   +27 more
core   +1 more source

Low-temperature Formation of Carbonaceous Dust Grains from PAHs

The Astrophysical Journal, 2020
Abstract Carbon is ubiquitous in space and plays a key role in prebiotic chemistry. Astronomical observations have found interstellar carbon in the form of polycyclic aromatic hydrocarbons (PAHs) as well as carbonaceous dust, confirming its presence in both gaseous and solid phases. The goal of this study is to experimentally investigate
Lisseth Gavilan Marin, Salma Bejaoui, Michael Haggmark, Nathan Svadlenak, Mattanjah de Vries, Ella Sciamma-O’Brien, Farid Salama   +6 more
openaire   +1 more source

Fluid evolution in CM carbonaceous chondrites tracked through the oxygen isotopic compositions of carbonates [PDF]

, 2017
The oxygen isotopic compositions of calcite grains in four CM carbonaceous chondrites have been determined by NanoSIMS, and results reveal that aqueous solutions evolved in a similar manner between parent body regions with different intensities of ...
Alexander, Alexander, Barber, Benedix, Bland, Bonal, Bunch, Burbine, Clark, Clayton, Clayton, de Leuw, DuFresne, Emery, Fujiya, Fujiya, Guo, Hewins, Horita, Howard, I.A. Franchi, Jenniskens, Johnson, Kasuga, Lauretta, Lee, Lee, Lee, Lee, Lee, Lee, Lindgren, Lindgren, M.R. Lee, Marrocchi, McSween, McSween, N.A. Starkey, P. Lindgren, Palguta, Rubin, Rubin, Starkey, Tomeoka, Tyra, Tyra, Tyra, Velbel, Young, Young   +49 more
core   +2 more sources

Formation of CO2 Driven by Photochemistry of Water Ice Mixed with Carbon Grains

The Astrophysical Journal, 2023
We present results on photochemistry of carbon-grains/water-ice mixtures at temperatures from 10 to 150 K. Such a temperature range corresponds to the physical conditions found in molecular clouds, hot cores and corinos, protostellar envelopes, and ...
Alexey Potapov, Dmitry Semenov, Cornelia Jäger, Thomas Henning   +3 more
doaj   +1 more source