Results 81 to 90 of about 8,526 (198)

A hybrid moment equation approach to gas-grain chemical modeling [PDF]

, 2011
[Context] The stochasticity of grain chemistry requires special care in modeling. Previously methods based on the modified rate equation, the master equation, the moment equation, and Monte Carlo simulations have been used. [Aims] We attempt to develop a
Awad, B. Parise, Barzel, Barzel, Barzel, Biham, Biham, Caselli, Chang, Charnley, Charnley, Charnley, Charnley, Cuppen, F. Du, Garrod, Garrod, Garrod, Gillespie, Gillespie, Gillespie, Gillespie, Green, Hasegawa, Hasegawa, Lipshtat, Mattis, McQuarrie, Menten, Ohkubo, Rae, Stantcheva, Stantcheva, Stantcheva, Tielens, Tielens, Vasyunin, Vasyunin, Woodall   +38 more
core   +2 more sources

Can We Draw Conclusions on Supernova Shock Wave Propagation Using Short‐Lived Radioactive Isotopes?

Astronomische Nachrichten, Volume 346, Issue 3-4, March-May 2025.
ABSTRACT We run a three‐dimensional Galactic chemical evolution (GCE) model to follow the propagation of 53Mn (exclusively produced from type Ia supernovae, SNIa), 60Fe (exclusively produced from core‐collapse supernovae, CCSNe), 182Hf (exclusively produced from intermediate mass stars, IMSs), and 244Pu (exclusively produced from neutron star mergers ...
Benjamin Wehmeyer, Andrés Yagüe López, Benoit Côté, Maria K. Petö, Chiaki Kobayashi, Maria Lugaro   +5 more
wiley   +1 more source

Infrared Spectra of Solid HCN Embedded in Various Molecular Environments for Comparison with the Data Obtained with JWST

The Astrophysical Journal Letters
Hydrogen cyanide (HCN) molecules serve as an important tracer for the chemical evolution of elemental nitrogen in the regions of star and planet formation.
Maksim Ozhiganov, Mikhail Medvedev, Varvara Karteyeva, Ruslan Nakibov, Uliana Sapunova, Vadim Krushinsky, Ksenia Stepanova, Anastasia Tryastsina, Aleksandr Gorkovenko, Gleb Fedoseev, Anton Vasyunin   +10 more
doaj   +1 more source

Astrochemical Pathways to Complex Organic and Prebiotic Molecules: Experimental Perspectives for In Situ Solid-State Studies

Life, 2021
A deep understanding of the origin of life requires the physical, chemical, and biological study of prebiotic systems and the comprehension of the mechanisms underlying their evolutionary steps.
Daniele Fulvio, Alexey Potapov, Jiao He, Thomas Henning   +3 more
doaj   +1 more source

Reaction Networks For Interstellar Chemical Modelling: Improvements and Challenges

, 2010
We survey the current situation regarding chemical modelling of the synthesis of molecules in the interstellar medium. The present state of knowledge concerning the rate coefficients and their uncertainties for the major gas-phase processes -- ion ...
Agundez, M., Cuppen, H. M., Geppert, W., Herbst, E., Linnartz, H., Loison, J. C., Oberg, K., Pernot, P., Roueff, E., Smith, I. W. M., Talbi, D., Troe, J., Wakelam, V.   +12 more
core   +3 more sources

Linear or Cyclic? Theoretical Investigation of Astrophysically Relevant Magnesium‐Bearing MgCnH Carbon Chains and Related Isomers

Journal of Computational Chemistry, Volume 46, Issue 2, January 15, 2025.
The global minimum energy structure of astrophysically relevant MgCnH systems is linear when n is even, and cyclic when n is odd. ABSTRACT Magnesium‐containing molecules, including MgC2H, MgC4H, and MgC6H, have been detected in the interstellar medium, largely facilitated by their high dipole moments.
A. Karolyna M. S. Gomes, Ricardo R. Oliveira, Thiago M. Cardozo, Felipe Fantuzzi   +3 more
wiley   +1 more source

Interstellar formation of lactaldehyde, a key intermediate in the methylglyoxal pathway

Nature Communications
Aldehydes are ubiquitous in star-forming regions and carbonaceous chondrites, serving as essential intermediates in metabolic pathways and molecular mass growth processes to vital biomolecules necessary for the origins of life.
Jia Wang, Chaojiang Zhang, Joshua H. Marks, Mikhail M. Evseev, Oleg V. Kuznetsov, Ivan O. Antonov, Ralf I. Kaiser   +6 more
doaj   +1 more source

Refit to numerically problematic UMIST reaction rate coefficients

, 2011
Aims. Chemical databases such as the UMIST Database for Astrochemistry (UDFA) are indispensable in the numerical modeling of astrochemical networks.
Baulch, Garrod, Hollenbach, Jorfi, Lique, M. Röllig, Quéméner, Röllig, Röllig, Wakelam, Woodall   +10 more
core   +1 more source

Tentative detection of ethylene glycol toward W51/e2 and G34.3+0.2 [PDF]

, 2015
How complex organic - and potentially prebiotic - molecules are formed in regions of low- and high-mass star-formation remains a central question in astrochemistry.
Bergin, Edwin A., Favre, Cécile, Jørgensen, Jes K., Lykke, Julie M.   +3 more
core   +1 more source

Phenyl Radical Activates Molecular Hydrogen Through Protium and Deuterium Tunneling

Angewandte Chemie International Edition, Volume 63, Issue 51, December 16, 2024.
Activating the strong H2 bond is typically reserved for transition metals, and only a few main group systems can tackle this challenge. Here, we explore a phenyl radical mediated pathway utilizing the photolysis of iodobenzene. The phenyl radical leverages the high C−H bond energy of the forming benzene to drive H2 activation.
Virinder Bhagat, Jan Meisner, Jan Philipp Wagner   +2 more
wiley   +1 more source