Results 121 to 130 of about 17,877 (291)

The galactic globular cluster M5 (NGC 5904) as a particle physics laboratory

EPJ Web of Conferences, 2013
Globular clusters have been used for a long time to test stellar evolution theories, and in particular to constrain novel forms of energy loss in low-mass stars.
Redondo J., Raffelt G.G., Viaux N., Catelan M., Valcarce A.A.R.   +4 more
doaj   +1 more source

EBSD Study of Creep‐Induced Lattice Misorientation in MgO‐Particle‐Reinforced Austenitic Steel Composites

Advanced Engineering Materials, EarlyView.
Creep experiments at 900°C on coarse‐grained steel‐ceramic composites containing recycled magnesia reveal that higher ceramic volume fractions significantly enhance the creep resistance. Detailed EBSD investigations identify subgrain formation in the steel matrix as the dominant deformation mechanism.
Moritz Müller, Amaya Compart, Mahnaz Mehdizadehlima, Serhii Yaroshevskyi, Christos G. Aneziris, Horst Biermann, Anja Weidner   +6 more
wiley   +1 more source

Reduction of Oxide Inclusions During the High‐Frequency Welding of Steel via a Nonthermal Ar/H2 Plasma Jet

Advanced Engineering Materials, EarlyView.
High‐frequency (HF) welding of steel is limited by oxide inclusions that degrade weld quality. This study demonstrates, for the first time, the integration of a nonthermal Ar/H2 dielectric barrier discharge (DBD) plasma jet into HF welding. Local plasma treatment provides effective shielding and in‐situ oxide reduction, resulting in markedly fewer and ...
Viktor Udachin, Lienhard Wegewitz, René Gustus, Henning Wiche, Wolfgang Maus‐Friedrichs   +4 more
wiley   +1 more source

Influence of an Argon/Silane Atmosphere on the Temperature of a Thermal Plasma

Advanced Engineering Materials, EarlyView.
The influence of a silane‐doped argon atmosphere on the chemical composition and temperature of a thermal nontransferring argon plasma is investigated using optical emission spectroscopy. As a result of the high amount of free electrons resulting from the stepwise ionization and dissociation of the silane molecule, even a silane addition of 0.01 vol ...
Lena Kreie, David Kramer, Thomas Scheithauer, Hans Jürgen Maier, Thomas Hassel   +4 more
wiley   +1 more source

Tayler Instability Revisited

The Astrophysical Journal
Tayler instability of toroidal magnetic fields B _ϕ is broadly invoked as a trigger for turbulence and angular momentum transport in stars. This paper presents a systematic revision of the linear stability analysis for a rotating, magnetized, and stably ...
Valentin A. Skoutnev, Andrei M. Beloborodov   +1 more
doaj   +1 more source

Handbook of Establishing and Maintaining Oxygen‐Free Atmospheres

Advanced Engineering Materials, EarlyView.
This study presents a practical framework for creating oxygen‐free atmospheres at ambient pressure using silane‐doped inert gases. The results show that ultra‐low oxygen levels and strongly reduced water content can be achieved through controlled silane dosing, drying systems, and sensor monitoring.
Sascha Jan Zimmermann, René Gustus, Lienhard Wegewitz, Wolfgang Maus‐Friedrichs   +3 more
wiley   +1 more source

3D Simulations of Semiconvection in Spheres: Turbulent Mixing and Layer Formation

The Astrophysical Journal
Semiconvection occurs in regions of stars and planets that are unstable to overturning convection according to the Schwarzschild criterion, but stable according to the Ledoux criterion.
J. R. Fuentes
doaj   +1 more source

Effect of Oxygen Content on Surface and Subsurface Integrity During Turning of Ti–6Al–4V

Advanced Engineering Materials, EarlyView.
This study examines how oxygen content in the ambient atmosphere affects the surface and subsurface properties of Ti–6Al–4V during turning. Results show that oxygen does not influence surface roughness. However, machining in an extremely high vacuum‐adequate atmosphere increases surface hardness by up to 7.8% and induces compressive residual stresses ...
Benjamin Bergmann, Berend Denkena, Hilke Petersen, Florian Schaper   +3 more
wiley   +1 more source

Competition between gravity waves excited by convection and tides in stars that host a companion

Astronomy & Astrophysics
Context. Asteroseismology has become a powerful diagnostic tool in stellar astrophysics, offering unprecedented insights into the internal structures and dynamics of stars.
Esseldeurs M., Ahuir J., Amard L., Mathis S., Decin L.   +4 more
doaj   +1 more source

Oxide‐Free Titanium Coatings by Wire Arc Spraying in a Silane‐Doped Inert Atmosphere

Advanced Engineering Materials, EarlyView.
A silane‐doped argon atmosphere enables the production of oxide‐free titanium coatings via twin‐wire arc spraying at ambient pressure. This innovative approach eliminates residual oxygen, creating process conditions that prevent oxidation and nitride formation.
Manuel Rodriguez Diaz, Maik Szafarska, René Gustus, Kai Möhwald, Hans Jürgen Maier   +4 more
wiley   +1 more source