Results 11 to 20 of about 24,969 (196)

Kinetics of the tautomerization of thioimidic acids R−C(SH)NH → R−C(S)NH2: For R = H, F, HO, CN, NC, H2N, HC(O), HC(S), HC≡ C, CH3, CF3, H2C=CH, HOCH2, H2NCH2,CH3C(O), C2H5, (CH3)2CH, C6H5

open access: yesInternational Journal of Chemical Kinetics, Volume 55, Issue 11, Page 731-742, November 2023., 2023
Abstract The kinetics of the tautomerization of thio‐imidic acids RC(SH)NH were determined at low (50–300 K) and high (500–1500 K) temperatures as R was varied to encompass mono‐ and diatomic species H, F, HO, NC, CN through H2N, HC(O), HC(S), HC≡ C, H3C, F3C, HOCH2, H2C=CH, CH3C(O), H2NCH2 and including ethyl, isopropyl and phenyl groups. The presence
Judith Würmel, John M. Simmie
wiley   +1 more source

Bulk mineralogy, water abundance, and hydrogen isotope composition of unequilibrated ordinary chondrites

open access: yesMeteoritics &Planetary Science, Volume 58, Issue 9, Page 1365-1381, September 2023., 2023
Abstract The origin and transport of water in the early Solar System is an important topic in both astrophysics and planetary science, with applications to protosolar disk evolution, planetary formation, and astrobiology. Of particular interest for understanding primordial water transport are the unequilibrated ordinary chondrites (UOCs), which have ...
Helen Grant   +6 more
wiley   +1 more source

Loading of Amino Acids onto RNA in a Putative RNA‐Peptide World

open access: yesAngewandte Chemie International Edition, Volume 62, Issue 21, May 15, 2023., 2023
The loading of RNAs with amino acids constitutes the first step toward RNA‐based peptide synthesis in a putative prebiotic RNA‐peptide world. The efficient loading of RNA strands incorporating N‐methylcarbamoyl nucleotides with a series of amino acids is reported. The loaded RNA strands also underwent RNA‐based amino acid transfer reactions.
Johannes N. Singer   +7 more
wiley   +1 more source

The grain size distribution of matrix in primitive chondrites

open access: yesMeteoritics &Planetary Science, Volume 58, Issue 5, Page 688-704, May 2023., 2023
Abstract The matrix of primitive chondrites is composed of submicron crystals embedded in amorphous silicates. These grains are thought to be the remains of relatively unprocessed dust from the inner regions of the protoplanetary disk. The matrix of primitive meteorites is often compared to chondritic porous interplanetary dust particles (CP‐IDPs ...
E. Vaccaro   +4 more
wiley   +1 more source

Lifetime of the Outer Solar System Nebula From Carbonaceous Chondrites

open access: yesJournal of Geophysical Research: Planets, Volume 127, Issue 7, July 2022., 2022
Abstract The evolution and lifetime of protoplanetary disks (PPDs) play a central role in the formation and architecture of planetary systems. Astronomical observations suggest that PPDs evolve in two timescales, accreting onto the star for up to several million years (Myr) followed by gas dissipation within ≲1 Myr. Because solar nebula magnetic fields
Cauê S. Borlina   +3 more
wiley   +1 more source

[Retracted] Internet of Things System of Spatial Structure Sports Events Health Monitoring Based on Cloud Computing

open access: yesSecurity and Communication Networks, Volume 2022, Issue 1, 2022., 2022
At present, the health monitoring system of world sports events uses the system's on‐site information or periodic test information to evaluate the health of the system. In order to make the data more accurate, the application of cloud computing is necessary.
Rui Feng, Ning Chang, Muhammad Arif
wiley   +1 more source

What Can Meteorites Tell Us About the Formation of Jupiter?

open access: yesAGU Advances, Volume 2, Issue 2, June 2021., 2021
Abstract Gas giants like Jupiter are a fundamental component of planetary systems, but how they formed has been uncertain. Here we discuss how paleomagnetic records in meteorites of the solar nebula may tell us about Jupiter's final growth stage. We suggest that under certain testable assumptions, the meteorite data indicate that proto‐Jupiter grew ...
Benjamin P. Weiss, William F. Bottke
wiley   +1 more source

Magnetic Effects Promote Supermassive Star Formation in Metal-enriched Atomic-cooling Halos

open access: yesThe Astrophysical Journal, 2023
Intermediate-mass black holes (with ≥10 ^5 M _⊙ ) are promising candidates for the origin of supermassive black holes (with ∼10 ^9 M _⊙ ) in the early universe (redshift z ∼ 6).
Shingo Hirano   +2 more
doaj   +1 more source

Protostellar jets: A statistical view with the CALYPSO IRAM-PdBI survey [PDF]

open access: yesEPJ Web of Conferences, 2022
In the context of the CALYPSO IRAM-PdBI Lai•ge Program we performed the first statistical survey of protostellar jets by analysing molecular emission in a sample of 21 protostars covering a broad range of internal luminosities (Lint from 0.035 L⊙ to 47 L⊙
Podio Linda   +2 more
doaj   +1 more source

Episodic excursions of low-mass protostars on the Hertzsprung-Russell diagram [PDF]

open access: yes, 2018
Following our recent work devoted to the effect of accretion on the pre-main-sequence evolution of low-mass stars, we perform a detailed analysis of episodic excursions of low-mass protostars in the Hertzsprung-Russell (H-R) diagram triggered by strong ...
Elbakyan, Vardan G.   +6 more
core   +2 more sources

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