Results 41 to 50 of about 1,113,005 (163)

Deep Search for Phosphine in a Prestellar Core

The Astrophysical Journal Letters
Understanding in which chemical forms phosphorus exists in star- and planet-forming regions and how phosphorus is delivered to planets are of great interest from the viewpoint of the origin of life on Earth.
Kenji Furuya, Takashi Shimonishi
doaj   +1 more source

The futuristic manifolds of REM sleep

Journal of Sleep Research, Volume 34, Issue 2, April 2025.
Summary Since one of its first descriptions 70 years ago, rapid eye movement sleep has continually inspired and excited new generations of sleep researchers. Despite significant advancements in understanding its neurocircuitry, underlying mechanisms and microstates, many questions regarding its function, especially beyond the early neurodevelopment ...
Liborio Parrino, Ivana Rosenzweig
wiley   +1 more source

Molecules in diffuse interstellar clouds [PDF]

, 1988
The existence of diatomic molecules in the diffuse interstellar gas has been known since the late thirties and from that time numerous observations have been made, at visible and ultraviolet wavelengths, of interstellar molecular absorption lines in the ...
Smith, Colin Adrian
core   +1 more source

Enantioselective Synthesis of a New Class of Stable and Functionalized Cyclopentadienes via CuH‐Catalysis

Angewandte Chemie, Volume 138, Issue 32, 3 August 2026.
Cyclopentadienes (CpHs) are fundamental building blocks with widespread applications in chemistry. However, their inherent acidity and isomeric instability have long limited access to chiral variants in an asymmetric fashion. Here, we introduce a CuH‐catalyzed asymmetric transformation that provides an unprecedented entry into a new class of ...
Piero Soppelsa, Riccardo Bellin, Besma Boulila, Francesco Vaghi, Manuel Orlandi   +4 more
wiley   +2 more sources

A Framework for Incorporating Binding Energy Distribution in Gas-ice Astrochemical Models

The Astrophysical Journal
One of the most serious limitations of current astrochemical models with the rate equation (RE) approach is that only a single type of binding site is considered in grain surface chemistry, although laboratory and quantum chemical studies have found that
Kenji Furuya
doaj   +1 more source

Photochemical effects of Mars‐like UV irradiation on carboxylic acids in carbonaceous chondrites and expectations for abiotic background organics on Mars

Meteoritics &Planetary Science, EarlyView.
Abstract In the search for life on Mars, understanding the origin of preserved organics is critical. Expected sources include exogenous delivery, endogenous synthesis, and potentially life. Environmental processing by ultraviolet (UV) irradiation can alter these organics, obscuring hallmarks of their origin. To deconvolve these effects, we conducted an
D. K. Buckner, J. C. Aponte, A. C. Schuerger, D. I. Foustoukos, F. Seguin, M. B. Wilhelm, G. Cooper, A. J. Williams   +7 more
wiley   +1 more source

Organic Chemistry in the H2-bearing, CO-rich Interstellar Ice Layer at Temperatures Relevant to Dense Cloud Interiors

The Astrophysical Journal
Ice chemistry in the dense, cold interstellar medium (ISM) is probably responsible for the formation of interstellar complex organic molecules (COMs). Recent laboratory experiments performed at T ∼ 4 K have shown that irradiation of CO:N _2 ice samples ...
Rafael Martín-Doménech, Alexander DelFranco, Karin I. Öberg, Mahesh Rajappan   +3 more
doaj   +1 more source

A Possible Chemical Clock in High-mass Star-forming Regions: N(HC3N)/N(N2H+)?

The Astrophysical Journal Supplement Series, 2023
We conducted observations of multiple HC _3 N ( J = 10−9, 12−11, and 16−15) lines and the N _2 H ^+ ( J = 1−0) line toward a large sample of 61 ultracompact (UC) H ii regions, through the Institut de Radioastronomie Millmétrique 30 m and the Arizona ...
Y. X. Wang, J. S. Zhang, H. Z. Yu, Y. Wang, Y. T. Yan, J. L. Chen, J. Y. Zhao, Y. P. Zou   +7 more
doaj   +1 more source

The Role of Terahertz and Far-IR Spectroscopy in Understanding the Formation and Evolution of Interstellar Prebiotic Molecules

Frontiers in Astronomy and Space Sciences, 2021
Stellar systems are often formed through the collapse of dense molecular clouds which, in turn, return copious amounts of atomic and molecular material to the interstellar medium.
Duncan V. Mifsud, Duncan V. Mifsud, Perry A. Hailey, Alejandra Traspas Muiña, Olivier Auriacombe, Nigel J. Mason, Sergio Ioppolo   +6 more
doaj   +1 more source

Photochemistry of interstellar molecules [PDF]

, 1971
The photochemistry of two diatomic and eight polyatomic molecules is discussed quantitatively. For an interstellar molecule, the lifetime against photodecomposition depends upon the absorption cross section, the quantum yield or probability of ...
Stief, L. J.
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