Results 91 to 100 of about 853,118 (283)

New oscillation results to fourth order delay differential equations with damping

Electronic Journal of Qualitative Theory of Differential Equations, 2016
This paper is concerned with the oscillation of the linear fourth order delay differential equation with damping \begin{equation*} \left(r_3(t)\left(r_2(t)\left(r_1(t)y'(t)\right)'\right)'\right)'+p(t)y'(t)+q(t)y(\tau(t))=0 \end{equation*} under the ...
Jozef Džurina, Blanka Baculíková, Irena Jadlovská   +2 more
doaj   +1 more source

Fourth-Order Ricci Gravity

, 2000
The Euler-Lagrange equations of motion for the most general Ricci type gravitational Lagrangians are derived by means of a purely metric formalism.
Borowiec, A., Francaviglia, M., Smirichinski, V. I.   +2 more
openaire   +2 more sources

Impact of Pre‐Oxidation Treatments on a Recycled MgO/Steel‐Composite as Carbon Free Anode in Aluminum‐Electrolysis Environments

Advanced Engineering Materials, EarlyView.
Cermets (60 vol.% AISI 316L stainless steel, 40 vol.% recycled MgO), intended for use in aluminum electrolysis, were pre‐oxidized in three furnaces with different heating technologies and subjected to a cryolite corrosion test. The different atmospheres influenced the formation of oxide layers, which in turn affected corrosion resistance and ...
Patricia Kaiser, Felix Drechsler, Nora Brachhold, Florian Kerber, Christos G. Aneziris   +4 more
wiley   +1 more source

High‐Temperature Nanoindentation of Metals: Assessing Thermal Drift, Frame Compliance, and Chemical Composition Effects on the Reported Mechanical Properties

Advanced Engineering Materials, EarlyView.
Do not let thermal drift and instrument artifacts deceive high‐temperature nanoindentation results. We compare classical Oliver–Pharr and automatic image recognition analyses across steels and a Ni alloy to quantify these effects. Accounting for artifacts reveals systematic softening with temperature, while Cr and Ni additions boost resistance ...
Velislava Yonkova, Steffen Brinckmann, Ruth Schwaiger   +2 more
wiley   +1 more source

Workflow for Design of Experiments‐Based Modeling of Species Transport and Growth Kinetics in GaN Hydride Vapor Phase Epitaxy

Advanced Engineering Materials, EarlyView.
A novel workflow for investigating hydride vapor phase epitaxy for GaN bulk crystal growth is proposed. It combines Design of experiments (DoE) with physical simulations of mass transport and crystal growth kinetics, serving as an intermediate step between DoE and experiments.
J. Tomkovič, G. Lukin, H. Torkashvand, A. Kerschbaum, M. Müller, S. Besendörfer, J. Heitmann, J. Friedrich   +7 more
wiley   +1 more source

Fourth order elliptic system with dirichlet boundary condition

Journal of Inequalities and Applications, 2011
We investigate the multiplicity of the solutions of the fourth order elliptic system with Dirichlet boundary condition. We get two theorems. One theorem is that the fourth order elliptic system has at least two nontrivial solutions when λ k < c &
Choi Q-Heung, Jung Tacksun
doaj  

Production of MgO/TiC Composites From MgO‐C Recyclates Using Spark Plasma Sintering

Advanced Engineering Materials, EarlyView.
Using the spark plasma sintering technique, MgO/TiC composites are manufactured from recycled MgO‐C refractories stemming from the steel production that were mixed with titanium powder. This article shows, how the size of the Ti grains and their distribution in the powder mixture affect the local carbon concentration in TiC.
Jiayan Yu, Christian Schimpf, Stefan Martin, David Rafaja   +3 more
wiley   +1 more source

Copper Nanocrystallization in Anodic Oxide Films of Ti–Cu‐Based Bulk Metallic Glass and Its Effect on the Corrosion Resistance and Cytocompatibility

Advanced Engineering Materials, EarlyView.
Viktoriia Shtefan, Thorgund Nemec, Ute Hempel, Annett Gebert and coworkers demonstrate that anodic treatment of Ti–Cu‐based metallic glass in a nontoxic pyrophosphate electrolyte forms a protective bilayered Ti/Zr‐oxide film enriched with Cu nanocrystals.
Viktoriia Shtefan, Nora Fernández Navas, Thorgund Nemec, Ivan Kaban, Ute Hempel, Andrea Voss, Volker Hoffmann, Darius Pohl, Annett Gebert   +8 more
wiley   +1 more source

Demonstration of an All‐Optical AND Gate Mediated by Photochromic Molecules

Advanced Functional Materials, EarlyView.
A logic AND gate that runs on photons is demonstrated. It relies on two spatially separated photochromic molecules that work in tandem. Abstract The realization of a photonic logic AND gate, i.e. a logic AND gate that runs on photons rather than electrons, and where all steps are controlled by light, is demonstrated. In a proof‐of‐principle experiment,
Heyou Zhang, Max Gießübel, Pankaj Dharpure, Andrea Albert, Vira Niestierkina, Paul Mulvaney, Mukundan Thelakkat, Jürgen Köhler   +7 more
wiley   +1 more source

Fourth order Weyl gravity

Physical Review D, 2006
The fourth order Weyl gravity theory of Mannheim and Kazanas is based on replacing the Einstein-Hilbert action with the square of the Weyl tensor, and on modifying the matter action of the standard model of particle physics to make it conformally invariant. This theory has been suggested as a model of both dark matter and dark energy. We argue that the
openaire   +2 more sources