Results 81 to 90 of about 13,045 (261)
Multiplicity of forced oscillations for scalar differential equations
Electronic Journal of Differential Equations, 2001 We give, via topological methods, multiplicity results for small periodic perturbations of scalar second order differential equations. In particular, we show that the equation $$ ddot{x} = g(x)+varepsilon f(t,x,dot x), $$ where $g$ is $C^1$ and $f$ is ...
Massimo Furi +2 more
doaj
Resolving the Structural Duality of Graphene Grain Boundaries
Advanced Materials, EarlyView.Cantilever ncAFM resolves the atomic structure of grain boundaries in graphene, revealing coexisting stable and metastable types. Both contain pentagon/heptagon defects, but metastable GBs show irregular geometries. Modeling shows metastable GBs form under compression, exhibiting vertical corrugation, while stable GBs are flat.
Haojie Guo +11 more
wiley +1 more source
Sensitivity analysis of stochastically forced quasiperiodic self-oscillations
Electronic Journal of Differential Equations, 2016 We study a problem of stochastically forced quasi-periodic self-oscillations of nonlinear dynamic systems, which are modelled by an invariant torus in the phase space.
Irina Bashkirtseva, Lev Ryashko
doaj
A Functional 2D Carbon Allotrope Combining Nanoporous Graphene and Biphenylene Segments
Advanced Materials, EarlyView.The synthesis of a novel nanoporous graphene (NPG) is reported with biphenylene segments via thermal fusion of 12‐armchair porous graphene nanoribbons grown on gold surfaces. Characterization using STM, AFM, and DFT reveals low‐defect semiconducting behaviour and tunable band gaps.
Paula Angulo‐Portugal +14 more
wiley +1 more source
A two-degree-of-freedom of motion mechanical oscillatory system with excitation and limit cycle oscillation: Automatic armament case [PDF]
Scientific Technical Review, 2016 This paper presents a numerical analysis of motion dynamics of a two-degree-of-freedom of motion rectilinear oscillatory system with the motion limitations and forced excitation.
Banjac Zdravko, Jovanović Snežana
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Opportunities of Semiconducting Oxide Nanostructures as Advanced Luminescent Materials in Photonics
Advanced Materials, EarlyView.The review discusses the challenges of wide and ultrawide bandgap semiconducting oxides as a suitable material platform for photonics. They offer great versatility in terms of tuning microstructure, native defects, doping, anisotropy, and micro‐ and nano‐structuring. The review focuses on their light emission, light‐confinement in optical cavities, and
Ana Cremades +7 more
wiley +1 more source
Intelligent Acousto‐Electrical Metamaterials (IAM) for Sound Source Detection
Advanced Materials, EarlyView.Our proposed metamaterial concept enables sound source detection using a single material, in contrast to conventional arrays that require dozens or even hundreds of transducers. We show that the coupled acoustic–vibrational–electrical responses in piezoelectric metamaterials give rise to topology‐governed charge transport, producing distinct voltage ...
Victor Couëdel +7 more
wiley +1 more source
UNSTEADY SHOCK WAVE – TURBULENT BOUNDARY LAYER INTERACTION IN THE LAVAL NOZZLE
TASK Quarterly, 2005 The flow in transonic diffusers and supersonic air intakes often becomes unsteady due to shock wave-boundary layer interaction. Oscillations may be induced by natural separation unsteadiness or forced by boundary conditions.
PIOTR DOERFFER +2 more
doaj
Comprehensive analysis of the mechanical system system “fixture – workpiece” [PDF]
Журнал інженерних наук, 2017 Present work is devoted to locating and clamping of prismatic parts in fixtures during the machining on drilling-milling-boring machines. The special feature of locating schemes of parts of the present type is that one of the flat surfaces is used as a ...
V. Ivanov, I. Pavlenko
doaj
Mechanically Programmable DNA Hydrogel Microparticles for 3D Cellular Systems
Advanced Materials, EarlyView.DNA hydrogel microparticles are designed to exhibit controllable viscoelasticity and stiffness across three orders of magnitude from 30Pa$30 \,\mathrm{Pa}$ to 6.5kPa$6.5 \,\mathrm{kPa}$. They are uptaken into fibroblast spheroids where they are actively remodeled by cellular forces depending on their mechanical properties.
Tobias Walther +9 more
wiley +1 more source