Results 81 to 90 of about 489,121 (293)
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 +8 more
wiley +1 more source
Can Dark Stars Account for the Star Formation Efficiency Excess at Very High Redshifts?
The Astrophysical JournalThe James Webb Space Telescope (JWST) has recently conducted observations of massive galaxies at high redshifts, revealing a notable anomaly in their star formation efficiency (SFE).
Lei Lei +5 more
doaj +1 more source
Radioactive and kinematic tracers of feedback from massive stars
EPJ Web of Conferences, 2012 The mixing of ejecta from young stars into the interstellar medium is an important process in the interplay between star formation and galaxy evolution.
Voss R.
doaj +1 more source
Shaping of Planetary Nebulae by Exoplanets
Galaxies, 2020 (1) Background: We investigate the hypothesis that exoplanet engulfment can help explain the observed non-spherical planetary nebula population, as a complementary shaping mechanism to the binary hypothesis.
Nicola Keaveney +2 more
doaj +1 more source
Mass loss and stellar superwinds [PDF]
, 2016 Mass loss bridges the gap between massive stars and supernovae (SNe) in two major ways: (i) theoretically it is the amount of mass lost that determines the mass of the star prior to explosion, and (ii) observations of the circumstellar material around SNe may teach us the type of progenitor that made the SN.
arxiv +1 more source
A Case‐Based Reasoning Approach to Model Manufacturing Constraints for Impact Extrusion
Advanced Engineering Materials, EarlyView.A hybrid modeling approach is presented that combines constraint‐based process modeling and case‐based reasoning. The model formalizes manufacturing constraints and integrates simulation data to model complex manufacturing processes. The approach supports manufacturability analysis during product design through an adaptive modeling environment.
Kevin Herrmann +5 more
wiley +1 more source
Gravitational Collapse and Neutrino Emission of Population III Massive Stars
, 2005 Pop III stars are the first stars in the universe. They do not contain metals and their formation and evolution may be different from that of stars of later generations.
Ken’ichiro Nakazato +4 more
core +1 more source
Were All Massive Stars Born in OB Associations and Clusters? [PDF]
arXiv, 2007 It has been commonly conjectured that all massive >10 Msun stars are born in OB associations or clusters. Many O and B stars in the Galaxy or the Magellanic Clouds appear to exist in isolation, however. While some of these field OB stars have been ejected from their birthplaces, some are too far away from massive star forming regions to be runaways ...
arxiv
Advanced Engineering Materials, EarlyView.In this study, how friction‐welding parameters (rotational speed, etc.) affect the morphology, distribution, and local thickness of the intermetallic compound layer (IMC‐layer) in friction‐welded steel‐aluminum hybrid components is investigated. In the results, it is shown that lower speeds (700 rpm) lead to a more uniform, thinner IMC‐layer (<0.5 μm),
Christoph Kahra +6 more
wiley +1 more source
Star Formation in the Ultraviolet
Galaxies, 2020 With the launch of JWST and the upcoming installation of extremely large telescopes, the first galaxies in our Universe will finally be revealed.
Jorick S. Vink
doaj +1 more source