Results 121 to 130 of about 16,662 (218)

Addition Reactions of Phosphorus‐Centered Radicals Onto Olefins: Interplay Between Stability and Reactivity

Chemistry – A European Journal, Volume 32, Issue 16, 25 April 2026.
The energetics of the addition reaction of P‐centered radicals onto alkenes are primarily ruled by the stability of the attacking radical, as outlined by the computational screening of a wide range of reactions. In addition, donor‐acceptor substituents at the olefin have an important tuning role.
Meng Yang, Julianna Oláh, Zoltán Benkő   +2 more
wiley   +1 more source

Non-equilibrium photodissociation regions [PDF]

, 1995
We discuss the theory of coupled ionization--dissociation fronts produced when molecular clouds are exposed to \lambda < 1110\AA\ radiation from hot stars.
Bertoldi, F, Draine, B T
core  

Matryoshka Holes: Nested Emission Rings in the Transitional Disk Oph IRS 48

, 2012
The processes that form transition disks - disks with depleted inner regions - are not well understood; possible scenarios include planet formation, grain growth and photoevaporation.
Alexander, Andrews, Andrews, Andrews, Andrews, Artymowicz, Brown, Brown, Brown, Brown, Bryden, Calvet, Dong, Foreman-Mackey, Hartmann, Hughes, Hughes, Hughes, Kraus, Loinard, Luhman, Lynden-Bell, Motte, Muto, Panic, Pinilla, Pontoppidan, Salyk, Thalmann, Zhu   +29 more
core   +1 more source

Do Eclipse‐Induced Thermospheric TADs Originate From Above or Below?

Geophysical Research Letters, Volume 53, Issue 7, 16 April 2026.
Abstract Solar eclipses generate significant wave activity in the Earth's upper atmosphere. The source region of eclipse‐induced Traveling Atmospheric Disturbances (TADs) in the upper thermosphere—particularly the relative contributions of gravity waves from the thermosphere itself versus the lower atmosphere—remains unknown. Using the Whole Atmosphere
Yu Jiao, Jing Liu, Shuhan Li, Joseph M. McInerney, Jianyong Li, Yuyan Yang   +5 more
wiley   +1 more source

Unveiling Stellar Feedback and Cloud Structure in the ρ Ophiuchi-A Region Using ALMA and JWST: Discovery of Substellar Cores, C18O Striations, and Protostellar Outflows

The Astrophysical Journal
In clustered star-forming regions, stellar feedback, such as H ii regions/photon-dominated regions (PDRs), and protostellar jets/outflows, shapes cloud structures and influences star formation. Using high-resolution Atacama Large Millimeter/submillimeter
Fumitaka Nakamura, Ryohei Kawabe, Shuo Huang, Kazuya Saigo, Naomi Hirano, Shigehisa Takakuwa, Takeshi Kamazaki, Motohide Tamura, James Di Francesco, Rachel Friesen, Kazunari Iwasaki, Chihomi Hara   +11 more
doaj   +1 more source

HONO formation mechanisms and impacts on ambient oxidants in coastal regions of Fujian, China [PDF]

Atmospheric Chemistry and Physics
Nitrous acid (HONO) is a vital precursor of hydroxyl radicals (OH) in the troposphere, leading to the formation of secondary air pollutants, including ozone (O3) and secondary aerosols.
H. Zhang, C. Shi, C. Shi, C. Ying, C. Ying, S. Weng, E. Ni, E. Ni, L. Zhao, P. Yang, K. Tang, X. Zhou, C. Ren, X. Chi, D. Zhou, M. Li, N. Li, T. Liu, X. Huang   +18 more
doaj   +1 more source

Molecular Hydrogen Emission from Photodissociation Regions [PDF]

International Astronomical Union Colloquium, 1989
AbstractWe review new observational and theoretical developments of the understanding of the H2 infrared emission in the last 5 years since the discovery of the fluorescent emission in NGC 2023. An excitation analysis of H2 in a variety of Galactic sources has revealed that in many sources the excitation is expressed as a mixture of thermal and ...
openaire   +1 more source

Spatial distribution of organics in the Horsehead nebula: Signposts of chemistry driven by atomic carbon

Astronomy & Astrophysics
Complex organic molecules (COMs) are considered essential precursors to prebiotic species in the interstellar and circumstellar medium. Despite their astrobiological relevance, many aspects of the formation of COMs remain unclear, particularly the role ...
Hernández-Vera Claudio, Guzmán Viviana V., Pety Jérôme, Wong Ka Tat, Goicoechea Javier R., Le Petit Franck, Gerin Maryvonne, den Braber Aquiles, Carpenter John M., Maillard Vincent, Bron Emeric, Gratier Pierre, Roueff Evelyne   +12 more
doaj   +1 more source

Deuterated Polycyclic Aromatic Hydrocarbons in the Interstellar Medium: Constraints from the Orion Bar as Observed by the James Webb Space Telescope

The Astrophysical Journal
The gas-phase abundances of deuterium (D) in the local interstellar medium exhibit considerable regional variations. Particularly, in some regions the gas-phase D abundances are substantially lower than the primordial D abundance generated in the Big ...
X. J. Yang, Aigen Li
doaj   +1 more source

Packet narrowing and quantum entanglement in photoionization and photodissociation

, 2004
The narrowing of electron and ion wave packets in the process of photoionization is investigated, with the electron-ion recoil fully taken into account.
A. E. Kazakov, A. Ekert, C. K. Law, H. Huang, J. H. Eberly, J. H. Eberly, K. W. Chan, L. D. Landau, M. A. Efremov, M. A. Nielsen, M. V. Fedorov, M. V. Fedorov   +11 more
core   +1 more source