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Observing the collapse of super-Bloch oscillations in strong-driving photonic temporal lattices

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Advanced Photonics 2024年第4期6卷 14-24页

作者： Xinyuan Hu Shulin Wang Chengzhi Qin Chenyu Liu Lange Zhao Yinglan Li Han Ye Weiwei Liu Stefano Longhi Peixiang Lu Bing Wang Huazhong University of Science and Technology School of Physics Wuhan National Laboratory for Optoelectronics Wuhan Institute of Technology Hubei Key Laboratory of Optical Information and Pattern Recognition Politecnico di Milano Dipartimento di Fisica IfISC (UIB-CSIC) Instituto de Fisica Interdisciplinary Sistemas Complejos

Super-Bloch oscillations(SBOs) are amplified versions of direct current(dc)-driving Bloch oscillations realized under the detuned dc-and alternating current(ac)-driving electric fields. A unique feature of SBOs is the coherent oscillation inhibition via the ac-driving renormalization effect, which is dubbed as the collapse of SBOs. However, previous experimental studies on SBOs have only been limited to the weak ac-driving regime, and the collapse of SBOs has not been observed. Here, by harnessing a synthetic temporal lattice in fiber-loop systems, we push the ac-field into a strong-driving regime and observe the collapse of SBOs, which manifests as the oscillation-trajectory localization at specific ac-driving amplitudes and oscillation-direction flip by crossing collapse points. By adopting arbitrary-wave ac-driving fields, we also realize generalized SBOs with engineered collapse conditions. finally, we exploit the oscillation-direction flip features to design tunable temporal beam routers and splitters. We initiate and demonstrate the collapse of SBOs, which may feature applications in coherent wave localization control for optical communications and signal processing.

关键词： Electric fields Optical modulators Phase modulation Bessel functions Optical coherence Polarization Pulse signals Solids Physical coherence Signal processing

Laws of Zipf and Benford, intermittency, and critical fluctuations

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Chinese Science Bulletin 2011年第34期56卷 3643-3648页

作者： ROBLEDO Alberto instituto de física Universidad Nacional Autónoma de México Grupo Interdisciplinar de sistemas complejos Departamento de Matemáticas Universidad Carlos III de Madrid

We describe precise equivalences between theoretical descriptions of: (i) size-rank and first-digit laws for numerical data sets, (ii) intermittency at the transition to chaos in nonlinear maps, and (iii) cluster fluctuations at criticality. The equivalences stem from a common statistical-mechanical structure that departs from the usual via a one-parameter deformation of the exponential and logarithmic functions. The generalized structure arises when configurational phase space is incompletely visited such that the accessible fraction has fractal properties. Thermodynamically, the common focal expression is an (incomplete) Legendre transform between two entropy (or Massieu) potentials. The theory is in quantitative agreement with real size-rank data and it naturally includes the bends or tails observed for small and large rank.

关键词：间歇性法律波动 Legendre变换变形结构非线性映射理论描述统计力学

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Self-assembly of highly ordered DNA origami lattices at solid-liquid interfaces by controlling cation binding and exchange

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Nano Research 2020年第11期13卷 3142-3150页

作者： Yang Xin Salvador Martinez Rivadeneira Guido Grundmeier Mario Castro Adrian Keller Technical and Macromolecular Chemistry Paderborn UniversityPaderborn33098Germany Grupo Interdisciplinar de sistemas complejos and instituto de Investigación Tecnológica Universidad Pontificia Comillas de MadridMadrid28015Spain

The surface-assisted hierarchical self-assembly of DNA origami lattices represents a versatile and straightforward method for the organization of functional nanoscale objects such as proteins and ***,we demonstrate that controlling the binding and exchange of different monovalent and divalent cation species at the DNA-mica interface enables the self-assembly of highly ordered DNA origami lattices on mica *** development of lattice quality and order is quantified by a detailed topological analysis of high-speed atomic force microscopy(HS-AfM)*** find that lattice formation and quality strongly depend on the monovalent cation ***^(+)is more effective than Li^(+)and K^(+)in facilitating the assembly of high-quality DNA origami lattices,because it is replacing the divalent cations at their binding sites in the DNA backbone more *** regard to divalent cations,Ca^(2+)can be displaced more easily from the backbone phosphates than Mg^(2+)and is thus superior in guiding lattice *** independently adjusting incubation time,DNA origami concentration,and cation species,we thus obtain a highly ordered DNA origami lattice with an unprecedented normalized correlation length of *** the correlation length,we use computer vision algorithms to compute the time course of different topological observables that,overall,demonstrate that replacing MgCl_(2) by CaCl_(2) enables the synthesis of DNA origami lattices with drastically increased lattice order.

关键词： DNA origami self-assembly lattice formation high-speed atomic force microscopy topological analysis

Electrochemical reduction of Cr(Ⅵ)in the presence of sodium alginate and its application in water purification

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Journal of Environmental Sciences 2021年第3期33卷 304-312页

作者： Bryan Butter Paola Santander Guadalupe del CPizarro Diego POyarzún federico Tasca Julio Sánchez facultad de Química y Biología Universidad de Santiago de ChileUSACHCasilla 40Correo 33SantiagoChile departamento de Química Universidad Tecnológica MetropolitanaJ.P.Alessandri 1242SantiagoChile Laboratorio de Nanotecnología Recursos Naturales y Sistemas ComplejosFacultad de Ciencias NaturalesUniversidad de AtacamaCopayapu 485CopiapóChile

Chromium(Cr)is used in many manufacturing processes,and its release into natural waters is a major environmental problem *** concentrations of Cr(Ⅵ)are toxic to human health and living organisms due to the carcinogenic and mutagenic nature of this *** work examined the conversion of Cr(Ⅵ)to Cr(Ⅲ)via electrochemical reduction using gold electrode in an acidic sodium alginate(SA)solution and subsequent removal of the produced Cr(Ⅲ)-SA by the polymer-enhanced ultrafiltration(PEUf)technique.A solution of SA in nitric acid was used both as an electrolytic medium during the voltammetric measurements and bulk electrolysis and as an extracting agent during the PEUf *** electroanalysis of Cr(Ⅵ)was performed by linear sweep voltammetry in the presence of acidic SA solution to study its voltammetric behavior as a function of the Cr(Ⅵ)concentration,pH,presence of Cr(Ⅲ),SA concentration and scan *** addition,the quantitative reduction of Cr(Ⅵ)to Cr(Ⅲ)was studied through the bulk electrolysis *** results showed efficient reduction with well-defined peaks at approximately 0.3 V ***/AgCl,using a gold working *** the pH increased,the reduction signal strongly decreased until its *** optimum SA concentration was 10 mmol/L,and it was observed that the presence of Cr(Ⅲ)did not interfere in the Cr(Ⅵ)*** the quantitative reduction by bulk electrolysis in the presence of acidic SA solution,it was possible to reduce all Cr(Ⅵ)to Cr(Ⅲ)followed by its removal via PEUf.

关键词： Alginate solution Chromium Electroanalytical chemistry Ultrafiltration Water purification

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first record of Odontaster penicillatus populations(Philippi,1870)(Echinodermata:Asteroidea)in the Atacama and Antofagasta regions,Chile(Southeast Pacific)

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Acta Oceanologica Sinica 2022年第12期41卷 152-155页

作者： Leonardo Campos fernando Berrios Brenda BHermosillo-Núñez Marco Ortiz departamento de Ciencias Acuáticas y Ambientales Universidad de Antofagasta ChileAntofagasta 1240000Chile Centro de Investigaciones Costeras Universidad de Atacama(CIC-UDA) Avenida Copayapu 485Copiapó1530000Chile Laboratorio de Modelamiento de sistemas Ecológicos complejos(LAMSEC) Instituto AntofagastaUniversidad de AntofagastaAntofagasta 1240000Chile instituto de Ciencias Naturales AvH Facultad de Ciencias del Mar y Recursos BiológicosUniversidad de AntofagastaAntofagasta 1240000Chile Centro de Investigación y Estudios Avanzados del Maule Vicerrectoría de Investigación y PosgradoUniversidad Católica Del MauleCampus San MiguelTalca 3480094Chile

We report for the first time the presence of local populations of the starfish Odontaster penicillatus in the regions of Atacama and Antofagasta,*** finding indicates an extension of the distribution limit of 500 km with respect to the last observation made in 2007 in Isla Grande de Atacama.A total of 121 specimens of *** were recorded at depths of between 8 m and 24 *** were associated with rocky substrate and with different species of barnacles,sponges and *** presence of *** expands the knowledge of the benthic biodiversity of the region,and the development of studies on its ecological importance will be promoted.

关键词： Odontaster penicillatus new record Antofagasta Atacama South Pacific Ocean

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Conformable and Caputo’s derivatives in Generalized Viscoelastic Models

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Applied Mathematics 2023年第9期14卷 580-601页

作者： Jorge fujioka Rosalío fernando Rodríguez Áurea Espinosa-Cerón instituto de física Dpto. de Sistemas Complejos Universidad Nacional Autónoma de México Ciudad de México México facultad de Ciencias Universidad Nacional Autónoma de México Ciudad de México México

We study two generalized versions of a system of equations which describe the time evolution of the hydrodynamic fluctuations of density and velocity in a linear viscoelastic fluid. In the first of these versions, the time derivatives are replaced by conformable derivatives, and in the second version left-handed Caputo’s derivatives are used. We show that the solutions obtained with these two types of derivatives exhibit significant similarities, which is an interesting (and somewhat surprising) result, taking into account that the conformable derivatives are local operators, while Caputo’s derivatives are nonlocal operators. We also show that the solutions of the generalized systems are similar to the solutions of the original system, if the order α of the new derivatives (conformable or Caputo) is less than one. On the other hand, when α is greater than one, the solutions of the generalized systems are qualitatively different from the solutions of the original system.

关键词： Conformable derivatives Caputo’s derivatives fractional derivatives Viscoelastic fluids Hydrodynamic fluctuations

Mesoscopic model for binary fluids

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frontiers of physics 2017年第5期12卷 231-239页

作者： C. Echeverria K. Tucci O. Alvarez-Llamoza E. E. Orozco-Guillén5 M. Morales M. G. Cosenza CeSiMo Universidad de Los Andes Mérida 5251 Mérida Venezuela Grupo de Caos y sistemas complejos Centro de Fisica Fundamental Universidad de Los Andes Mérida Venezuela departamento de fisica FACYT Universidad de Carabobo Valencia Venezuela facultad de Ingenierla Universidad Católica de Cuenca Ecuador programa Académico de Ingenierla en Energla Universidad Politécnica de Sinaloa 82199 Mazatldn Mexico Programa Académico de Ingenierla en Nanoteenologla Universidad Politécnica de Sinaloa 82199 Mazatldn Mexico

We propose a model for studying binary fluids based on the mesoscopic molecular simulation technique known as multiparticle collision, where the space and state variables are continuous, and time is discrete. We include a repulsion rule to simulate segregation processes that does not require calculation of the interaction forces between particles, so binary fluids can be described on a mesoscopic scale. The model is conceptually simple and computationally efficient; it maintains Galilean invariance and conserves the mass and energy in the system at the micro- and macro-scale, whereas momentum is conserved globally. for a wide range of temperatures and densities, the model yields results in good agreement with the known properties of binary fluids, such as the density profile, interface width, phase separation, and phase growth. We also apply the model to the study of binary fluids in crowded environments with consistent results.

关键词： multiparticle collision dynamics mesoscopic models phase separation interface dynamics

Geometrodynamical Analysis to Characterize the Dynamics and Stability of a Molecular System through the Boundary of the Hill’s Region

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Applied Mathematics 2014年第16期5卷 2630-2642页

作者： Alberto Vergel Rosa M. Benito Juan C. Losada florentino Borondo Grupo de sistemas complejos Departamento de Física y Mecánica Escuela Técnica Superior de Ingenieros Agrónomos Universidad Politécnica de Madrid Madrid Spain instituto de Ciencias Matemáticas (ICMAT) Madrid Spain departamento de Química Universidad Autónoma de Madrid Madrid Spain

In this paper we study the dynamics and stability of a two-dimensional model for the vibrations of the LiCN molecule making use of the Riemannian geometry via the Jacobi-Levi-Civita equations applied to the Jacobi metric. The Stability Geometrical Indicator for short times is calculated to locate regular and chaotic trajectories as the relative extrema of this indicator. Only trajectories with initial conditions at the boundary of the Hill’s region are considered to characterize the dynamics of the system. The importance of the curvature of this boundary for the stability of trajectories bouncing on it is also discussed.

关键词： Geometrodynamical Analysis Molecular Nonlinear Dynamics Stability Geometrical Indicator Riemannian Geometry Hamiltonian Systems

Non-Linear Semi-Quantum Hamiltonians and Its Associated Lie Algebras

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Applied Mathematics 2014年第20期5卷 3277-3296页

作者： Claudia M. Sarris Angelo Plastino Ciclo Bá sico Comú n-Cá tedra de fí sica Universidad de Buenos Aires Buenos Aires Argentina Laboratorio de sistemas complejos Departamento de Matem&#225 tica Facultad de Ingenier&#237 a Universidad de Buenos Aires Buenos Aires Argentina instituto de fí sica La Plata-CCT-CONICET Universidad Nacional de La Plata La Plata Argentina Physics department and IfISC-CSIC University of the Balearic Islands Palma de Mallorca Spain

We show that the non-linear semi-quantum Hamiltonians which may be expressed as(whereis the set of generators of some Lie algebra and are the classical conjugated canonical variables) always close a partial semi Lie algebra under commutation and, because of this, it is always possible to integrate the mean values of the quantum degrees of freedom of the semi-quantum non-linear system in the fashion:(whereis the Maximum Entropy Principle density operator) and, so, these kind of Hamiltonians always have associated dynamic invariants which are expressed in terms of the quantum degrees of freedom’s mean values. Those invariants are useful to characterize the kind of dynamics (regular or irregular) the system displays given that they can be fixed by means of the initial conditions imposed on the semi-quantum non-linear system.

关键词： Non-Linear Semiquantum Dynamics Lie Algebras Maximum Entropy Principle