Results 81 to 90 of about 158,293 (319)

Detection of Silver in Metal-poor Stars

The Astronomical Journal, 1998
The resonance lines of neutral silver appearing at 3280, 3382 in the near-ultraviolet spectral region " have been identi-ed on Keck I HIRES spectra of four halo stars with metallicities (1.3 " (Fe/H) " (2.2. This represents the -rst detection in metal-poor stars of an element in the atomic number range 41 " Z " 55. The mean relative silver abundance is
Jeremy R. King, Christopher Sneden, Constantine P. Deliyannis, James Crawford, Ann Merchant Boesgaard, Ann Merchant Boesgaard   +5 more
openaire   +3 more sources

Novel Biologically Active Glass Fiber Functionalized Using Magnesium Phosphate Cement Promotes Bone and Vascular Regeneration

Advanced Biology, EarlyView.
In this study, a new type of bioactive glass fiber ‐based composite magnesium phosphate bone cement is prepared and verified that its mechanical strength and biological properties. In addition, the cement may have played a biologically active role in the Notch and HIF signaling pathways.
Yuzheng Lu, Yanbo Shan, Yingjie Xiong, Jianting Ye, Yanbin Wu, Jipeng Song, Yao Zhang, Wancheng Lin, Haoye Meng, Wenjing Xu, Jiang Peng, Qiang Lu, Lixiang Ding   +12 more
wiley   +1 more source

Carbon and Strontium Abundances of Metal‐poor Stars [PDF]

The Astrophysical Journal, 2007
We present carbon and strontium abundances for 100 metal-poor stars measured from R$\sim $7000 spectra obtained with the Echellette Spectrograph and Imager at the Keck Observatory. Using spectral synthesis of the G-band region, we have derived carbon abundances for stars ranging from [Fe/H]$=-1.3$ to [Fe/H]$=-3.8$.
David K. Lai, Jennifer A. Johnson, Michael Bolte, Sara Lucatello   +3 more
openaire   +3 more sources

The Regulation of Trace Metal Elements in Cancer Ferroptosis

Advanced Biology, EarlyView.
The induction of ferroptosis inhibits tumor growth, enhances anticancer efficacy, and overcomes drug resistance. Recent evidence shows nonferrous metal elements play a role in ferroptosis. This review focuses on how trace metals regulate ferroptosis processes like iron accumulation, lipid peroxidation, and antioxidant defense.
Xiaoyan Wang, Yuanyuan Xue, Lei Chang, Xuena Zhu, Wenjun Liu, Tingbo Liang   +5 more
wiley   +1 more source

Abundance Analysis of Stars at Large Radius in the Sextans Dwarf Spheroidal Galaxy

The Astrophysical Journal, 2023
We present the stellar parameters and chemical abundances of 30 elements for five stars located at large radii (3.5–10.7 times the half-light radius) in the Sextans dwarf spheroidal galaxy. We selected these stars using proper motions, radial velocities,
Ian U. Roederer, Andrew B. Pace, Vinicius M. Placco, Nelson Caldwell, Sergey E. Koposov, Mario Mateo, Edward W. Olszewski, Matthew G. Walker   +7 more
doaj   +1 more source

r-process enhanched metal-poor stars [PDF]

Proceedings of International Symposium on Nuclear Astrophysics - Nuclei in the Cosmos - IX — PoS(NIC-IX), 2010
In this review we summarize the current state of some aspects of observational studies of low metallicity stars that have been enriched with products of rapid-neutron-capture (r-process) nucleosynthesis events. Attention will be drawn to the element domains where there is little star-tostar variation in relative abundances (such as the rare earths ...
John J. Cowan, Elizabeth A. Den Hartog, Christopher Sneden, James E. Lawler   +3 more
openaire   +3 more sources

Development of Ternary Magnesium Alloys for Laser Powder Bed Fusion: Optimizing Oxide Layer Thickness

Advanced Engineering Materials, EarlyView.
Additive manufacturing of magnesium alloys by laser is difficult because the melting point of the oxide layer is much higher than the evaporation temperature of the metal underneath. Making the oxide layer thinner can solve this problem. Alloying magnesium with strontium makes the oxide layer thinner, especially at 0.5 wt%.
Elmar Jonas Breitbach, Stefan Julmi, Sabine Behrens, Tatiana Blank, Arvid Abel, Nicole Emminghaus, Ludger Overmeyer, Christian Klose, Hans Jürgen Maier   +8 more
wiley   +1 more source

Chemodynamically Tagged Groups of CEMP Stars in the Halo of the Milky Way. I. Untangling the Origins of CEMP-s and CEMP-no Stars

The Astrophysical Journal, 2023
We construct a sample of 644 carbon-enhanced metal-poor (CEMP) stars with abundance analyses based on moderate- to high-resolution spectroscopic studies.
Joseph Zepeda, Timothy C. Beers, Vinicius M. Placco, Derek Shank, Dmitrii Gudin, Yutaka Hirai, Mohammad Mardini, Colin Pifer, Thomas Catapano, Sean Calagna   +9 more
doaj   +1 more source

The Gaia-ESO Survey: the most metal-poor stars in the Galactic bulge

, 2014
We present the first results of the EMBLA survey (Extremely Metal-poor BuLge stars with AAOmega), aimed at finding metal-poor stars in the Milky Way bulge, where the oldest stars should now preferentially reside.
Asplund, M., Bensby, T., Bergemann, M., Bessell, M. S., Casagrande, L., Casey, A. R., Costado, M. T., Da Costa, G. S., Damiani, F., de Laverny, P., Feltzing, S., Flaccomio, E., Gilmore, G., Heiter, U., Hill, V., Hourihane, A., Howes, L., Jofré, P., Keller, S. C., Korn, A. J., Lardo, C., Lind, K., Magrini, L., Maiorca, E., Marino, A. F., Masseron, T., Minniti, D., Morbidelli, L., Nataf, D. M., Owen, C. I., Pancino, E., Prieto, C. Allende, Randich, S., Recio-Blanco, A., Sacco, G. G., Schmidt, B. P., Smiljanic, R., Tisserand, P., Vallenari, A., Worley, C., Yong, D., Zoccali, M.   +41 more
core   +1 more source

A Novel Approach to Produce Metal–Metal Composites by Leveraging Immiscibility: Laser Powder Bed Fusion of Nanosilver‐Dispersed Titanium

Advanced Engineering Materials, EarlyView.
Incorporating nanosized silver into titanium for antimicrobial materials exploits the metastable miscibility gap between silver and titanium. Silver nanoparticles are synthesized via pulsed laser ablation in liquid. Silver addition refines the microstructure, increases hardness by 30%, and reduces Staphylococcus capitis microbial adhesion by 70%, with ...
Hamed Shokri, Silja‐Katharina Rittinghaus, Janett Schmelzer, Jessica Bertrand, Bilal Gökce   +4 more
wiley   +1 more source