Results 131 to 140 of about 322,076 (276)

Vacuum Energy as Spectral Geometry

Symmetry, Integrability and Geometry: Methods and Applications, 2007
Quantum vacuum energy (Casimir energy) is reviewed for a mathematical audience as a topic in spectral theory. Then some one-dimensional systems are solved exactly, in terms of closed classical paths and periodic orbits. The relations among local spectral
Stephen A. Fulling
doaj  

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

Positive solutions for the Riemann–Liouville-type fractional differential equation system with infinite-point boundary conditions on infinite intervals

Boundary Value Problems
In this paper, we study the existence and uniqueness of positive solutions for a class of a fractional differential equation system of Riemann–Liouville type on infinite intervals with infinite-point boundary conditions.
Yang Yu, Qi Ge
doaj   +1 more source

A Numerical–Experimental Approach for Multi‐Matrix Fiber‐Reinforced Plastics Characterization Using Finite Element Model Updating

Advanced Engineering Materials, EarlyView.
A numerical–experimental framework is developed for characterizing multi‐matrix fiber‐reinforced polymers (MM‐FRPs) combining epoxy and polyurethane matrices. Harmonic bending tests are integrated with finite element model updating (FEMU) to simultaneously identify elastic and viscoelastic material parameters.
Rodrigo M. Dartora, Tales V. Lisbôa, Axel Spickenheuer, Rogério J. Marczak, Jakson M. Vassoler   +4 more
wiley   +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

Additive Gaussian Process Regression for Predictive Design of High‐Performance, Printable Silicones

Advanced Engineering Materials, EarlyView.
A chemistry‐aware design framework for tuning printable polydimethylsiloxane (PDMS) for vat photopolymerization (VPP) is developed using additive Gaussian process (GP) modeling. Polymer network mechanics informs variable groupings, feasible formulation constraints, and interaction variables.
Roxana Carbonell, Martha Leach, Hongtao Song, Carolyn Seepersad   +3 more
wiley   +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

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

Thermodynamic Pathways of Nonequilibrium Solidification in Wire‐Arc Additive Manufacturing Fe‐Based Multicomponent Alloy Structures

Advanced Engineering Materials, EarlyView.
Geometry‐driven thermal behavior in wire‐arc additive manufacturing (WAAM) influences microstructural evolution during nonequilibrium solidification of a chemically complex Fe–Cr–Nb–W–Mo–C nanocomposite system. By comparing different deposits configurations, distinct entropy–cooling rate correlations, segregation, and carbide evolution are revealed ...
Blanca Palacios, Anthony Gonzalez, Aleksander Aleman, Tyler Dolmetsch, Tanaji Paul, Arvind Agarwal   +5 more
wiley   +1 more source