Results 101 to 110 of about 158,293 (319)

Comparison of the Chemical Compositions between the Bright and Faint Red Clumps for the Metal-poor and Metal-rich Populations in the Milky Way Bulge

The Astrophysical Journal
We examined the double red clump (RC) observed in the Galactic bulge, interpreted as a difference in distance (“X-shaped bulge scenario”) or in chemical composition (“multiple population scenario”).
Seungsoo Hong, Dongwook Lim, Young-Wook Lee   +2 more
doaj   +1 more source

The Dependence of Iron-rich Metal-poor Star Occurrence on Galactic Environment Supports an Origin in Thermonuclear Supernova Nucleosynthesis

The Astronomical Journal, 2023
It has been suggested that a class of chemically peculiar metal-poor stars called iron-rich metal-poor (IRMP) stars formed from molecular cores with metal contents dominated by thermonuclear supernova nucleosynthesis.
Zachary Reeves, Kevin C. Schlaufman, Henrique Reggiani   +2 more
doaj   +1 more source

A Different Perspective on the Solid Lubrication Performance of Black Phosphorous: Friend or Foe?

Advanced Engineering Materials, EarlyView.
Researchers investigate black phosphorous (BP) as a standalone solid lubricant coating through ball‐on‐disc linear‐reciprocating sliding experiments in dry conditions. Testing on different metals shows BP doesn't universally reduce friction and wear. However, it achieves 33% friction reduction on rougher iron surfaces and 23% wear reduction on aluminum.
Matteo Vezzelli, Manel Rodríguez Ripoll, Sabine Schwarz, Ali Erdemir, Maria Clelia Righi, Carsten Gachot   +5 more
wiley   +1 more source

Towards the big picture of the Milky Way bulge

EPJ Web of Conferences, 2012
Evidence has been growing in the last few years that the Bulge is very complex, with maybe two or more components partially overlapping in space, kinematics and metallicity. An extensive mapping of these properties is necessary to disentangle them.
Gonzalez O.A.
doaj   +1 more source

Extremely metal-poor star candidates in the SDSS [PDF]

Research in Astronomy and Astrophysics, 2013
For a sample of metal-poor stars (-3.3< [Fe/H]
Huawei Zhang, Si-Yao Xu, Xiaowei Liu
openaire   +4 more sources

An abundance study of red-giant-branch stars in the Hercules dwarf spheroidal galaxy [PDF]

, 2010
Using high-resolution spectroscopy, we provide a determination of [Fe/H] and [Ca/H] for confirmed red-giant branch member stars of the Hercules dwarf spheroidal galaxy.
A. Koch, Adén, Adén, Alonso, Andrievsky, Aoki, Asplund, Belokurov, Bensby, Burris, Calamida, Calamida, Clem, Cohen, D. Adén, Dotter, E. K. Grebel, Edvardsson, Feltzing, Frebel, Frebel, Fulbright, Fulbright, Geisler, Gilmore, Gratton, Gratton, Gratton, Grebel, Grevesse, Gustafsson, Hanson, Helmi, Ivans, Ivans, Johnson, K. Eriksson, Kirby, Kirby, Kirby, Koch, Koch, Koch, Koch, Kupka, Kupka, Lind, M. I. Wilkinson, Martin, Matteucci, McWilliam, McWilliam, McWilliam, Nissen, Norris, Pasquini, Piskunov, Prochaska, Reddy, Ryabchikova, Ryan, S. Feltzing, Sadakane, Schlegel, Schörck, Shetrone, Shetrone, Simon, Simon, Starkenburg, Stephens, Tollerud, Tolstoy, VandenBerg, Venn, Walker, Woosley, Zucker   +77 more
core   +1 more source

A Perspective on Powder Metallurgy and Additive Manufacturing of High‐Nitrogen Alloyed Stainless Steels

Advanced Engineering Materials, EarlyView.
This perspective article explores an innovative powder metallurgical approach to producing high‐nitrogen steels by utilizing a mixture of stainless steel and Si3N4. This mixture undergoes hot isostatic pressing followed by direct quenching. The article also examines adapting this method to laser powder bed fusion (PBF‐LB/M) to overcome nitrogen ...
Louis Becker, Felix Radtke, Jonathan Lentz, Simone Herzog, Christoph Broeckmann, Sebastian Weber   +5 more
wiley   +1 more source

A Census of Thermally Pulsing AGB Stars in the Andromeda Galaxy and a First Estimate of Their Contribution to the Global Dust Budget

The Astrophysical Journal Supplement Series, 2022
We present a near-complete catalog of the metal-rich population of thermally pulsing asymptotic giant branch (AGB) stars in the northwest quadrant of M31.
Steven R. Goldman, Martha L. Boyer, Julianne Dalcanton, Iain McDonald, Léo Girardi, Benjamin F. Williams, Sundar Srinivasan, Karl Gordon   +7 more
doaj   +1 more source

Thermohaline Mixing in Extremely Metal-poor Stars [PDF]

The Astrophysical Journal Letters, 2018
Abstract Extremely metal-poor (EMP) stars are an integral piece in the puzzle that is the early universe, and although anomolous subclasses of EMP stars such as carbon-enhanced metal-poor (CEMP) stars are well studied, they make up less than half of all EMP stars with [Fe/H] ∼ −3.0.
Ross P. Church, Ross P. Church, Andrew R. Casey, John C. Lattanzio, Amanda I. Karakas, Kate Henkel   +5 more
openaire   +3 more sources

Advances in Hybrid Icing and Frosting Protection Strategies for Optics, Lens, and Photonics in Cold Environments Using Thin‐Film Acoustic Waves

Advanced Engineering Materials, EarlyView.
This article provides a comprehensive overview of fundamentals and recent advances of transparent thin‐film surface acoustic wave technologies on glass substrates for monitoring and prevention/elimination of fog, ice, and frost. Fogging, icing, or frosting on optical lenses, optics/photonics, windshields, vehicle/airplane windows, and solar panel ...
Hui Ling Ong, Zhangbin Ji, Luke Haworth, Yihao Guo, Jaime del Moral, Stefan Jacob, Ana Borras, Agustin R. Gonzalez‐Elipe, Jikai Zhang, Jian Zhou, Glen McHale, Yong‐Qing Fu   +11 more
wiley   +1 more source