Results 61 to 70 of about 24,728 (260)
Advanced Materials, EarlyView.A high‐capacity polyimide‐linked porous organic polymer (HAT‐PTO) incorporating numerous redox‐active centers is synthesized via a hydrothermal reaction, delivering a high theoretical capacity of 484 mAh g−1. In situ hybridization with carboxyl‐functionalized multiwalled carbon nanotubes enhances conductivity and stability, achieving 397 mAh g−1 at C ...
Arindam Mal +7 more
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On the algebraic properties of difference approximations of Hamiltonian systems
Discrete and Continuous Models and Applied Computational ScienceIn this paper, we examine difference approximations for dynamic systems characterized by polynomial Hamiltonians, specifically focusing on cases where these approximations establish birational correspondences between the initial and final states of the ...
Lyubov O. Lapshenkova +2 more
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Periodic perturbations of Hamiltonian systems
Advances in Nonlinear Analysis, 2016 We prove existence and multiplicity results for periodic solutions of Hamiltonian systems, by the use of a higher dimensional version of the Poincaré–Birkhoff fixed point theorem.
Fonda Alessandro +2 more
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Periodic solutions for a class of second-order Hamiltonian systems of prescribed energy
Electronic Journal of Qualitative Theory of Differential Equations, 2015 In this paper, the existence of non-constant periodic solutions for a class of conservative Hamiltonian systems with prescribed energy is obtained by the saddle point theorem.
Dong-Lun Wu, Chun Li, Pengfei Yuan
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NORMALIZATION OF CLASSICAL HAMILTONIAN SYSTEMS WITH TWO DEGREES OF FREEDOM
Физико-химические аспекты изучения кластеров, наноструктур и наноматериалов, 2020 The family of the Hamiltonian systems with two degrees of freedom was investigated. The calculations of the Poincaré sections show that with arbitrary values of the parameters of the Hamilton function, the system is non-integrable and dynamic chaos is ...
I.N. Belyaeva +4 more
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Homoclinic orbits of sub-linear Hamiltonian systems with perturbed terms
Boundary Value Problems, 2021 By using variational methods, we obtain the existence of homoclinic orbits for perturbed Hamiltonian systems with sub-linear terms. To the best of our knowledge, there is no published result focusing on the perturbed and sub-linear Hamiltonian systems.
Haiyan Lv, Guanwei Chen
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High Charge Carrier Mobility in Non‐Conjugated 3D Covalent Organic Frameworks
Advanced Materials, EarlyView.A non‐conjugated 3D COF constructed via boronate ester linkages from tetraphenylene and pyrene‐based monomers is reported, which exhibits a high charge carrier mobility of 14 ± 1 cm2 V−1 s−1. ABSTRACT π‐Conjugation, π–π stacking, and long‐range order play a central role in determining charge transport efficiency in organic materials.
Joaquín Almarza +11 more
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Gapless Superconductivity From Extremely Dilute Magnetic Disorder in 2H‐NbSe2‐xSx
Advanced Materials, EarlyView.We demonstrate that 2H‐NbSe2‐xSx hosts gapless superconductivity at unexpectedly low magnetic impurity concentrations. Combining STM, Bogoliubovde Gennes simulations, DFT, and quasiparticle interference, we comprehensively study the development of gapless behavior and show that SeS substitution reshapes the band structure, enhances nesting, and drives ...
Jose Antonio Moreno +16 more
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The Multiplicity Problem for Periodic Orbits of Magnetic Flows on the 2-Sphere
Advanced Nonlinear Studies, 2017 We consider magnetic Tonelli Hamiltonian systems on the cotangent bundle of the 2-sphere, where the magnetic form is not necessarily exact. It is known that, on very low and on high energy levels, these systems may have only finitely many periodic orbits.
Abbondandolo Alberto +4 more
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Advanced Materials, EarlyView.A Nb‐proximitized Josephson junction based on a WTe2/α‐Fe2O3 heterostructure exhibits a robust superconducting diode effect with programmable polarity. The diode direction can be trained by magnetic fields and switched by temperature cycling, revealing tunable finite‐momentum pairing states and competing superconducting states in symmetry‐broken ...
Enze Zhang +9 more
wiley +1 more source