Results 81 to 90 of about 36,750 (220)

Deciphering the “Missing Xenon Paradox” in Celestial Bodies: A Multifaceted Perspective Toward Demystifying This Enigma

Journal of Geophysical Research: Planets, Volume 131, Issue 4, April 2026.
Abstract Xenon (Xe) is a heavy noble gas with intriguing chemical properties, such as having several stable isotopes and the ability to form compounds under extreme conditions. Despite the predictions based on cosmochemical models that suggest xenon should be relatively abundant in planetary reservoirs, empirical data indicate a significant depletion ...
Avinash Kumar Both, Avradip Ghosh, Chin Li Cheung   +2 more
wiley   +1 more source

Dust extinction and absorption: the challenge of porous grains

, 2005
In many models of dusty objects in space the grains are assumed to be composite or fluffy. However, the computation of the optical properties of such particles is still a very difficult problem.
Dubkova, D. N., Henning, Th., Il'in, V. B., Voshchinnikov, N. V.   +3 more
core   +1 more source

Non-equilibrium chemistry and cooling in the diffuse interstellar medium - I. Optically thin regime [PDF]

, 2014
An accurate treatment of the multiphase interstellar medium (ISM) in hydrodynamic galaxy simulations requires that we follow not only the thermal evolution of the gas, but also the evolution of its chemical state, including its molecular chemistry ...
Oppenheimer, Benjamin D., Richings, Alexander J., Schaye, Joop   +2 more
core   +3 more sources

Integrin‐Binding Matricellular Protein Fibulin‐5 Maintains Epidermal Stem Cell Heterogeneity During Skin Aging

Aging Cell, Volume 25, Issue 4, April 2026.
Fibulin‐5 maintains epidermal stem cell heterogeneity during skin aging by linking the extracellular environment to YAP‐dependent intracellular signaling. Its loss reduces YAP activity and depletes the fast‐cycling epidermal stem cell population, recapitulating age‐associated changes in skin.
Wenxin Fan, Mizuho Ishikawa, Erna Raja, Ahmed M. Hegazy, Hinata Date, Yen Xuan Ngo, Yoshifumi Sato, Kazuya Yamagata, Hiromi Yanagisawa, Aiko Sada   +9 more
wiley   +1 more source

The Definitive Abundance of Interstellar Oxygen

The Astrophysical Journal, 1998
Using the Goddard High Resolution Spectrograph (GHRS) onboard HST, we have obtained high S/N echelle observations of the weak interstellar O I 1356 A absorption toward the stars Gamma Cas, Epsilon Per, Delta Ori, Epsilon Ori, 15 Mon, Tau CMa, and Gamma Ara. In combination with previous GHRS measurements in six other sightlines (Zeta Per, Xi Per, Lambda
Meyer, David M., Jura, M., Cardelli, Jason A.   +2 more
openaire   +2 more sources

Gas phase atomic metals in the circumstellar envelope of IRC+10216

, 2010
We report the results of a search for gas phase atomic metals in the circumstellar envelope of the AGB carbon star IRC+10216. The search was made using high resolution (R=50000) optical absorption spectroscopy of a backgound star that probes the envelope
Chaffee, Cherchneff, Coelho, Cordiner, Cox, Delgado Inglada, Dunbar, Field, Gilman, Glassgold, Highberger, Huggins, Huggins, Huggins, Jura, Kendall, Keyes, Kingdon, Kwan, Lafont, Lodders, Lodders, Loup, Martin, Mauron, Mauron, Mauron, McCabe, Middlemass, Morris, Morton, Morton, N. Mauron, Olofsson, P. J. Huggins, Péquignot, Ramstedt, Savage, Schöier, Tsuji, Turner, Young, Zhang, Ziurys, Ziurys, Ziurys, Ziurys   +46 more
core   +1 more source

Tracing the Ingredients for a Habitable Earth from Interstellar Space through Planet Formation [PDF]

, 2015
We use the C/N ratio as a monitor of the delivery of key ingredients of life to nascent terrestrial worlds. Total elemental C and N contents, and their ratio, are examined for the interstellar medium, comets, chondritic meteorites and terrestrial planets;
Bergin, Edwin A., Blake, Geoffrey A., Ciesla, Fred, Hirschmann, Marc M., Li, Jie   +4 more
core   +2 more sources

The Deuterium Fractionation of NH3 in Massive Star-forming Regions

The Astrophysical Journal
Deuteration is sensitive to environmental conditions in star-forming regions. To investigate NH _2 D chemistry, we compared the spatial distribution of ortho-NH _2 D ${1}_{11}^{s}-{1}_{01}^{a}$ , NH _3 (1,1), and NH _3 (2,2) in 12 late-stage massive star-
Yuqiang Li, Junzhi Wang, Juan Li, Prathap Rayalacheruvu, Liton Majumdar, Yaoting Yan, Donghui Quan, Xing Lu, Siqi Zheng   +8 more
doaj   +1 more source

Isotopic abundances in interstellar carbon monosulfide

The Astrophysical Journal, 1976
A survey of the relative abundances of the isotopic species, /sup 12/C/sup 32/S, /sup 12/C/sup 34/S, and /sup 13/C/sup 32/S has been made in 14 dense molecular clouds through observations of the J=3-1 rotational transitions at 3 mm. The abundance ratio, (/sup 13/C/sup 32/S)/(/sup 12/C/sup 34/S), is found to be 1.9 times greater in the galactic center ...
R. W. Wilson, A. A. Penzias, P. G. Wannier, R. A. Linke   +3 more
openaire   +1 more source

Model calculations for cosmogenic nuclides in meteorites and the lunar surface. 1. Long‐lived radionuclides

Meteoritics &Planetary Science, Volume 61, Issue 4, Page 600-620, April 2026.
Abstract Production rates for the cosmogenic radionuclides 10Be, 14C, 26Al, 36Cl, 41Ca, 53Mn, and 60Fe in a large variety of meteorites, that is, ordinary chondrites (H, L, LL), carbonaceous chondrites, HED meteorites, ureilites, Martian meteorites, and iron meteorites and in the uppermost ~2 m of the lunar surface are modeled.
Ingo Leya
wiley   +1 more source