Results 61 to 70 of about 293,009 (201)

Insights Into the Gas‐Phase Structure and Internal Dynamics of Diphenylsilane: A Broadband Rotational Spectroscopy Study

ChemPhysChem, Volume 26, Issue 2, January 14, 2025.
The structure of diphenylsilane could be determined from the rotational spectra of all its singly substituted heavy atom isotopologues. A comparison with its oxygen analogue diphenylether revealed some interesting differences in the internal dynamics as well as in the gas‐phase structure.
Gayatri Batra, Melanie Schnell
wiley   +1 more source

First direct detection of large polycyclic aromatic hydrocarbons on asteroid (162173) Ryugu samples: An interstellar heritage

Natural Sciences, Volume 4, Issue 4, October 2024.
Large free aromatic species, with up to 61 carbon atoms, were detected in grains of the Ryugu carbonaceous asteroid using ultra‐sensitive two‐step laser mass spectrometry. This discovery confirms the presence of large polycyclic aromatic hydrocarbons in the interstellar medium and provides new information on the formation and evolution of organic ...
Hassan Sabbah, Ghylaine Quitté, Karine Demyk, Christine Joblin   +3 more
wiley   +1 more source

Presolar He and Ne Isotopes in Single Circumstellar SiC Grains

The Astrophysical Journal, 2007
Noble gas isotopes in presolar silicon carbide (SiC) dust grains from primitive meteorites provide, together with major element isotopic compositions, insight into the nucleosynthetic output of different types of evolved stars >4.5 Gyr ago. We report here new results from helium and neon isotopic analyses of single presolar SiC grains with sizes ...
Rainer Wieler, Philipp R. Heck, Roberto Gallino, Peter Hoppe, Heinrich Baur, Kuljeet K. Marhas   +5 more
openaire   +3 more sources

Grain Size in the Class I Protostellar System TMC-1A Constrained with ALMA and Very Large Array Observations

The Astrophysical Journal
The disk mass and substructure in young stellar objects suggest that planet formation may start at the protostellar stage, through the growth of dust grains.
Yusuke Aso, Satoshi Ohashi, Hauyu Baobab Liu, Wenrui Xu   +3 more
doaj   +1 more source

Electron microscopy observations of the diversity of Ryugu organic matter and its relationship to minerals at the micro‐ to nano‐scale

Meteoritics &Planetary Science, Volume 59, Issue 8, Page 2023-2043, August 2024.
Abstract Transmission electron microscopy analyses of Hayabusa2 samples show that Ryugu organic matter exhibits a range of morphologies, elemental compositions, and carbon functional chemistries consistent with those of carbonaceous chondrites that have experienced low‐temperature aqueous alteration.
Rhonda M. Stroud, Jens Barosch, Lydie Bonal, Katherine Burgess, George D. Cody, Bradley T. De Gregorio, Luke Daly, Emmanuel Dartois, Elena Dobrică, Jean Duprat, Cecile Engrand, Dennis Harries, Minako Hashiguchi, Hope Ishii, Yoko Kebukawa, A. David Kilcoyne, Falko Langenhorst, Martin R. Lee, Larry R. Nittler, Eric Quirico, Taiga Okumura, Laurent Remusat, Scott Sandford, Hikaru Yabuta, Masanao Abe, Neyda M. Abreu, Paul A. J. Bagot, Pierre Beck, Laure Bejach, Phil A. Bland, John C. Bridges, Brittany A. Cymes, Alexandre Dazzi, Francisco de la Peña, Ariane Deniset‐Besseau, Satomi Enju, Yuma Enokido, David R. Frank, Jennifer Gray, Mitsutaka Haruta, Satoshi Hata, Leon Hicks, Yohei Igami, Damien Jacob, Kanami Kamide, Mutsumi Komatsu, Sylvain Laforet, Hugues Leroux, Corentin Le Guillou, Zita Martins, Maya Marinova, James Martinez, Jérémie Mathurin, Megumi Matsumoto, Toru Matsumoto, Junya Matsuno, Samuel McFadzean, Tatsuhiro Michikami, Itaru Mitsukawa, Akira Miyake, Masaaki Miyahara, Akiko Miyazaki, Gilles Montagnac, Smail Mostefaoui, Tomoki Nakamura, Aiko Nakato, Hiroshi Naraoka, Yusuke Nakauchi, Satoru Nakazawa, Masahiro Nishimura, Takaaki Noguchi, Kenta Ohtaki, Takuji Ohigashi, Tatsuaki Okada, Shota Okumura, Ryuji Okazaki, Thi H. V. Phan, Rolando Rebois, Kanako Sakamoto, Takanao Saiki, Hikaru Saito, Yusuke Seto, Miho Shigenaka, William Smith, Hiroki Suga, Mingqi Sun, Shogo Tachibana, Yoshio Takahashi, Yasuo Takeichi, Akihisa Takeuchi, Aki Takigawa, Yusuke Tamenori, Satoshi Tanaka, Fuyuto Terui, Michelle S. Thompson, Naotaka Tomioka, Akira Tsuchiyama, Yuichi Tsuda, Kentaro Uesugi, Masayuki Uesugi, Tomohiro Usui, Maximilien Verdier‐Paoletti, Daisuke Wakabayashi, Sei‐ichiro Watanabe, Toru Yada, Shohei Yamashita, Masahiro Yasutake, Kasumi Yogata, Makoto Yoshikawa, Hisayoshi Yurimoto, Pierre‐M. Zanetta, Thomas Zega, Michael E. Zolensky   +112 more
wiley   +1 more source

Extinct Radioactivities: Trapped Residuals of Presolar Grains [PDF]

, 1975
The xenon anomalies trapped in meteorites and the moon may have first been trapped in circumstellar grains formed in or outside of postexplosive stars. In that case, the initial solar nebula need not have contained most of their radioactive progenitors ...
Clayton, Donald D
core   +1 more source

Effects of Metallicity on Graphite, TiC, and SiC Condensation in Carbon Stars

The Astrophysical Journal
From transmission electron microscopy and other laboratory studies of presolar grains, the implicit condensation sequence of carbon-bearing condensates in circumstellar envelopes of carbon stars is (from first to last) TiC-graphite-SiC.
Gabrielle M. Adams, Katharina Lodders
doaj   +1 more source

Multiband ALMA Polarization Observations of BHB 07-11 Reveal Aligned Dust Grains in Complex Spiral Arm Structures

The Astrophysical Journal
Polarization-mode observations from the Atacama Large Millimeter/submillimeter Array (ALMA) are powerful tools for studying the dust grain populations in circumstellar disks.
Austen Fourkas, Leslie W. Looney, Zhe-Yu Daniel Lin, Martin Radecki, Zhi-Yun Li, John J. Tobin, Ian W. Stephens, Manuel Fernández-López, Haifeng Yang, Woojin Kwon, Rachel Harrison   +10 more
doaj   +1 more source

Commentary on the role of polyoxometalates in nature cybernetic loop

Natural Sciences, Volume 4, Issue 2-3, June-July 2024.
Polyoxometalates (POMs) are both synthetic and naturally occurring coordination compounds. In the biosphere, POMs can participate in many different life‐determining geochemical and biological processes. Future interdisciplinary research on POMs may reveal their potential for prebiotic and abiotic chemistry, as well as for the development of artificial ...
Kirill Yu. Monakhov
wiley   +1 more source

The destruction of dust grains in collisions of a supernova with a circumstellar medium [PDF]

Monthly Notices of the Royal Astronomical Society, 1985
Dust grains exist, if not abundantly, in systems composed of a Type II supernova and a circumstellar medium (CSM). The grains, however, may subsequently suffer intense sputtering by X-ray emitting plasmas during the collision of the supernova ejecta with the CSM.
openaire   +1 more source