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The search for trace elements in stardust silicate grains
2022Isotopically anomalous dust grains that formed in the outflows of evolved stars and in the ejecta of stellar explosions are a minor, but important component of primitive Solar System materials. These grains carry records of stellar nucleosynthesis and evolution, circumstellar grain formation, and stars contributing material to the nascent Solar System.
Leitner, Jan +2 more
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Carbon and silicate grains in the laboratory as analogues of cosmic dust
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2001Carbon and silicate grains are the two main components of cosmic dust. There is increasing spectroscopic evidence that their composition varies according to the cosmic environment and the experienced processing. Irradiation from ultraviolet photons and cosmic rays, as well as chemical interactions with the interstellar gas play a crucial role for grain
V, Mennella, J R, Brucato, L, Colangeli
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Thermal Processing of Formamide Ices on Silicate Grain Analogue
The Journal of Physical Chemistry A, 2014Fourier transform-infrared spectroscopy (FT-IR) and temperature programmed desorption (TPD) have been used to examine the thermal processing of three isotopes of pure formamide ice (HCONH2, DCONH2, and HCOND2) adsorbed on a SiO2 interstellar grain analogue.
Dawley, M. Michele +2 more
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The Infrared Characteristics of Circumstellar Silicate Grains
1985We have made a theoretical study of the infrared emission from circumstellar shells around late-type giants, with the aim of deriving the infrared characteristics of the silicate grains condensing in these shells. A large grid of models has been compared with observations of optically visible Miras, IRC sources and OH/IR stars.
W. Schutte, A. G. G. M. Tielens
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Silicate Grains in Space: Laboratory Results
1988Since their discovery in the spectra of some strong IR sources (Stein et al., 1969; Woolf and Ney, 1969; Forrest et al., 1979), the bands at around 10 µm and 20 µm have been respectively attributed to typical Si-O stretching and O-Si-0 bending modes in the SiO4 tetrahedra of the silicate structure. The presence of silicate grains around “O” stars ([O]/[
F. Leucci +3 more
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Penetration and corrosion of magnesia grain by silicate slags
British Ceramic Transactions, 2000AbstractPenetration and corrosion resistance of high purity sintered and fused magnesia grain by model EAF (CaO/SiO2 = 1·38) and BOF ‘late’ slags (CaO/SiO2 = 3·29) at 1600 and 1700°C were investigated by SEM, EDS, and XRD analysis. Thermodynamic calculations were performed to assist interpretation of the reaction processes involved.
S. Zhang +3 more
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Optical properties of circumstellar silicate grains
Astrophysics and Space Science, 1991The optical properties of circumstellar silicate dust grains around oxygen-rich giant stars are investigated with close attention to infrared observations of OH/IR stars. The optical constants are deduced from available astronomical and laboratory data.
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Radiation Processing of Formamide and Formamide:Water Ices on Silicate Grain Analogue
The Journal of Physical Chemistry A, 2014Lyman-α (121.6 nm) photon and 1 keV electron-beam irradiation of pure HCONH2 (FA) ice and H2O:HCONH2 ice mixtures on high-surface-area SiO2 nanoparticles have been investigated with FT-IR spectroscopy and temperature programmed desorption (TPD). Lyman-α photolysis of pure amorphous FA ice grown at 70 K and crystalline FA ice produced by annealing to ...
Dawley, M. Michele +2 more
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