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Science China Mathematics 2024年第3期67卷 627-646页

作者： Hui xiao Ion Grama Quansheng Liu Institut fur Mathematik und Angewandte Informatik Universitat HildesheimHildesheim 31141Germany Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China LMBA Universite Bretagne SudCNRS UMR 6205Vannes F-56000France

Let(g_(n))_(n≥1) be a sequence of independent and identically distributed positive random d×d matrices and consider the matrix product G_(n)=g_(n)…g_*** suitable conditions,we establish the Berry-Esseen bounds on the rate of convergence in the central limit theorem and Cramer-type moderate deviation expansions,for any matrix norm ‖G_(n)‖ of G_(n),its entries G_(n)^(i,j) and its spectral radius ρ(G_(n)).Extended versions of their joint law with the direction of the random walk G_(n)x are also established,where x is a starting point in the unit sphere of R~d.

关键词： Berry-Esseen bound Cramér-type moderate deviation product of random matrices operator norm entry spectral radius

Constant charge method or constant potential method:Which is better for molecular modeling of electrical double layers?

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Journal of Energy Chemistry 2024年第7期94卷 54-60页

作者： Liang Zeng xi Tan xiangyu Ji Shiqi Li Jinkai Zhang Jiaxing Peng Sheng Bi Guang Feng State Key Laboratory of Coal Combustion Schoolof Energy and PowerEngineeringHuazhong Universityof Science and Technology(HUST)Wuhan 430074HubeiChina Sorbonne universite CNRSPhysico-chimie des Electrolytes et Nanosystemes InterfaciauxPHENIXF-75005 ParisFrance

In molecular modeling of electrical double layers(EDLs),the constant charge method(CCM)is prized for its computational efficiency but cannot maintain electrode equipotentiality like the more resourceintensive constant potential method(CPM),potentially leading to *** certain scenarios,CCM can yield results identical to ***,there are no clear guidelines to determine when CCM is sufficient and when CPM is ***,we conduct a series of molecular simulations across various electrodes and electrolytes to present a comprehensive comparison between CCM and CPM under different charging *** reveal that CCM approximates CPM effectively in capturing equilibrium EDL and current-driven dynamics in open electrode systems featuring ionic liquids or regular concentration aqueous electrolytes,while CPM is indispensable in scenarios involving organic and highly concentrated aqueous electrolytes,nanoconfinement effects,and voltage-driven *** work helps to select appropriate methods for modeling EDL systems,prioritizing accuracy while considering computationalefficiency.

关键词： Electrochemical interface Molecular dynamics Electrode polarization modeling Nanoconfinement effect

A novel encoding mechanism for particle physics

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Nuclear Science and Techniques 2024年第8期35卷 153-166页

作者： Zhi‑Guang Tan Sheng‑Jie Wang You‑Neng Guo Hua Zheng Aldo Bonasera School of Electronic Information and Electrical Engineering Changsha UniversityChangsha 410003China School of Physics and Information Technology Shaanxi Normal UniversityXi’an 710119China Key Laboratory of Quark and Lepton Physics(MOE) Central China Normal UniversityWuhan 430079China Cyclotron Institute Texas A&M UniversityCollege StationTX 77843USA Laboratori Nazionali del sud INFN95123 CataniaItaly

This study proposes a novel particle encoding mechanism that seamlessly incorporates the quantum properties of particles,with a specific emphasis on constituent *** primary objective of this mechanism is to facilitate the digital registration and identification of a wide range of particle *** design ensures easy integration with different event generators and digital simulations commonly used in high-energy ***,this innovative framework can be easily expanded to encode complex multi-quark states comprising up to nine valence quarks and accommodating an angular momentum of up to 99/*** versatility and scalability make it a valuable tool.

关键词： Multi-quark state Encoding mechanism Constituent quark Particle physics

Direct observation of zero modes in a non-Hermitian optical nanocavity array

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Photonics Research 2022年第2期10卷 574-586页

作者： Flore Hentinger Melissa Hedir Bruno Garbin Mathias Marconi Li Ge Fabrice Raineri Juan A.Levenson Alejandro M.Yacomotti Centre de Nanosciences et de Nanotechnologies CNRSUniversite Paris-SudUniversite Paris-Saclay91120 PalaiseauFrance universite Cote d'Azur Institut de Physique de NiceCNRS-UMR 7010Sophia AntipolisFrance Department of Physics and Astronomy College of Staten IslandCUNYStaten IslandNew York 10314USA Graduate Center CUNYNew YorkNew York 10016USA universite de paris 75205 Paris Cedex 13France

Zero modes are symmetry protected ones whose energy eigenvalues have zero real parts. In Hermitian arrays, they arise as a consequence of the sublattice symmetry, implying that they are dark modes. In non-Hermitian systems that naturally emerge in gain/loss optical cavities, particle-hole symmetry prevails instead;the resulting zero modes are no longer dark but feature π∕2 phase jumps between adjacent cavities. Here, we report on the direct observation of zero modes in a non-Hermitian three coupled photonic crystal nanocavities array containing quantum wells. Unlike the Hermitian counterparts, the observation of non-Hermitian zero modes upon single pump spot illumination requires vanishing sublattice detuning, and they can be identified through far-field imaging and spectral filtering of the photoluminescence at selected pump locations. We explain the zero-mode coalescence as a parity-time phase transition for small coupling. These zero modes are robust against coupling disorder and can be used for laser mode engineering and photonic computing.

关键词： pump optical tuning

THERMODYNAMIQUE　DES　ENSEMBLES　DE　CANTOR　AUTOSIMILAIRES　（THERMODYNAMICS　OF　SELF－SIMILAR　CANTOR　SETS）

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Chinese Annals of Mathematics,Series B 1994年第3期15卷 253-272页

作者： G. MICHON J. PEYRIERE(University de Bourgogne, URA 755, BP 138, 21004 Dijon, dance.)(University de paris-sud, Centre d’Orsayl URA 757, 91405 Orsayt dance.) universite de Bourgogne 法国 universite de paris-sud 法国

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关键词：康托集图论维度理论力学吉布斯测度

Recapture probability, flight morphology, and microorganisms

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Current Zoology 2018年第3期64卷 277-283页

作者： Zaid AL RUBAIEE Haider AL-MURAYATI Anders Pape MФLLER Ecologie Systematique Evolution Universite Paris-Sud CNRS AgroParisTech Universite Paris-Saclay F-91405 Orsay Cedex France

Microorganisms on and within organisms are ubiquitous and interactions with their hosts range from mutualistic over commensal, to pathogenic. We hypothesized that microorganisms might affect the ability of barn swallows to escape from potential predators, with positive associations between the abundance of microorganisms and escape ability implying mutualistic effects, while negative associations would imply antagonistic effects. We quantified escape behavior as the ability to avoid capture in a mist net and hence as a small number of recaptures. Because recapture probability may also depend on timing of reproduction and reproductive success, we also tested whether the association between recapture and microorganisms was mediated by an association between recapture and life history. We found intermediate to strong positive relationships between recapture probability and abundance of , but not abundance of other bacteria or fungi. The abundance of was associated with an advance in laying date and an increase in reproductive success. However, these effects were independent of the number of recaptures. This interpretation is supported by the fact that there was no direct correlation between laying date and reproductive success on one hand and the number of recaptures on the other. These findings have implications not only for predator-prey interactions, but also for capture-mark-recapture analyses of vital rates such as survival and dispersal.

关键词：微生物概率形态学飞行相互作用食肉动物对抗效果调查结果

Fashion and out of fashion:appearance and disappearance of a novel nest building innovation

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Avian Research 2017年第2期8卷 71-75页

作者： Anders P.Møller Ecologie Systematique Evolution Universite Paris‑SudCNRSAgroParisTechUniversite Paris‑Saclay91405 Orsay CedexFrance

Background:Nests are composed of and built with different materials that are handled in specific ways. These mate?rials must initially have been used de novo before commonly being incorporated into nests. Plastic and plastic bags were invented in the 1950s, and they are widely distributed in the environment. Birds started picking up plastic from plastic used to cover farm produce such as silage, potatoes, beets and other crops for use in their nests in the ***:I recorded the frequency of such plastic use by the Blackbird(Turdus merula) in nests in Denmark, starting in 1966, followed by a peak in use in the 1970s and a subsequent ***:Nests with plastic were initially built earlier in the season than those without plastic, indicating an associa?tion between innovation and early reproduction. Plastic use was subsequently selected against because nests with plastic suffered from higher rates of predation than nests without plastic, probably because nests with plastic were easier to locate. However, the elevated risk of nest predation only applied to outdoor nests, but not to nests inside buildings, probably because visually searching nest predators such as corvids do not enter ***:These findings show that the dynamics of nest material use depend on the benefits of innovation and the fitness costs of nest predation.

关键词： Fashion Indoor breeding Innovation Nest predation Turdus merula

Experimental manipulation of size and shape of tail spots and sexual selection in barn swallows

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Current Zoology 2017年第5期63卷 569-572页

作者： Anders P. MOLLER Ecologie Systematique Evolution CNRS Universite Paris-Sud AgroParisTech Universite Paris-Saclay 0rsayF-91400 France

Barn swallows Hirundo rustica have white spots on their tail feathers, and they have been hypothe-sized to be a handicap because white spots are prone to feather breakage, ectoparasites are dispro-portionately common in white spots, and size of white spots increases with tail length. Here I testfor attractiveness of narrow and long tail spots by manipulation of their shape while using com-plete painting of spots and an absence of treatment as a control. Female barn swallows are knownto differentially invest in reproduction when mated to attractive males. Spot manipulation tookplace during laying of the first clutch, and there were no effects of treatment on clutch size or broodsize of first or second broods. In contrast, the incidence of second clutches and the total number ofeggs and fledglings produced during the breeding season was larger in males with painting of theside of tail spots rather than painting of the tip of spots, painting of entire spots, or no *** findings are consistent with the hypothesis that it is the shape rather than the size of tailspots that affects differential reproductive effort by female barn swallows.

关键词： Hirundo rustica, reliable signals, shape of tail spots, tail spots.

Mode selection and dispersion engineering in Bragg-like slot photonic crystal waveguides for hybrid light-matter interactions

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Photonics Research 2018年第1期9卷 54-60页

作者： samuel serna weiwei zhang thi hong cam hoang carlos alonso-ramos delphine marris-morini laurent vivien eric cassan Centre de Nanosciences et de Nanotechnologies UMR 9001 (CNRS/Universite Paris-Sud) Universite Paris-Saclay 91405 Orsay France

We introduce a family of slot photonic crystal waveguides(SPh CWs) for the hybrid integration of low-index active materials in silicon photonics with energy-confinement factors of ~30% in low-index regions. The proposed approach, which is based on a periodic indentation of the etched slot in the middle of the SPh CW, makes it possible to reconcile a simultaneously narrow and wide slot for exploiting the two modes of even symmetry of a SPh CW. The resulting mode-selection mechanism allows a flexible choice of the modes to be used. Furthermore,the proposed structure offers tremendous flexibility for adjusting the dispersive properties of the slot-confined modes, in particular of their slow-light effects. Flat band slow light in a bandwidth of about 60 nm with a group velocity dispersion factor jβ_2 j below 1 ps^2∕mm is numerically demonstrated by this approach, corresponding to a normalized delay bandwidth product of around 0.4. These results, obtained from hollow-core periodic waveguides that are directly designed in view of hybrid integration of active materials in mechanically robust structures(not based on free-standing membranes) could pave the way for the realization of on-chip slow-light bio-sensing,active hybrid-silicon optoelectronic devices, or all-optical hybrid-silicon nonlinear functionalities.

关键词：光子晶体波导通讯技术发展现状

First-principles study of the structural, electronic, and magnetic properties of double perovskite Sr2FeReO6 containing various imperfections

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Chinese Physics B 2016年第5期25卷 410-417页

作者：张研段理 Vincent Ji 徐可为 School of Materials Science and Engineering Chang'an University Xi 'an 710061 China ICMMO/SP2M UMR CNRS 8182 Universite Paris- Sud 91405 Orsay Cedex France State Key Laboratory for Mechanical Behavior of Materials Xi' an Jiaotong University Xi' an 710049 China

The structural, electronic, and magnetic properties of double perovskite Sr_2FeReO_6 containing eight different imperfections of FeReor ReFeantisites, Fe1–Re1 or Fe1–Re4 interchanges, V_（Fe）, V_（Re）, VOor V_（Sr） vacancies have been studied by using the first-principles projector augmented wave（PAW） within generalized gradient approximation as well as taking into account the on-site Coulomb repulsive interaction（GGA＋U）. No obvious structural changes are observed for the imperfect Sr_2FeReO_6 containing FeReor ReFeantisites, Fe1–Re1 or Fe1–Re4 interchanges, or VSrvacancy defects. However, the six（eight） nearest oxygen neighbors of the vacancy move away from（close to） VFeor V_（Re）（VO） vacancies. The half-metallic（HM） character is maintained for the imperfect Sr_2FeReO_6 containing FeReor ReFeantisites, Fe1–Re4 interchange, V_（Fe）,VO or V_（Sr） vacancies, while it vanishes when the Fe1–Re1 interchange or VRevacancy is presented. So the Fe1–Re1 interchange and the VRevacancy defects should be avoided to preserve the HM character of Sr_2FeReO_6 and thus usage in spintronic devices. In the FeReor ReFeantisites, Fe1–Re1 or Fe1–Re4 interchanges cases, the spin moments of the Fe（Re）cations situated on Re（Fe） antisites are in an antiferromagnetic coupling with those of the Fe（Re） cations on the regular sites. In the V_（Fe）, V_（Re）, VO, or V_（Sr） vacancies cases, a ferromagnetic coupling is obtained within each cation sublattice,while the two cation sublattices are coupled antiferromagnetically. The total magnetic moments μtot（μB/f.u.） of the imperfect Sr_2FeReO_6 containing eight different defects decrease in the sequence of VSrvacancy（3.50）, VRevacancy（3.43）,FeReantisite（2.74）, VOvacancy（2.64）, VFevacancy（2.51）, ReFeantisite（2.29）, Fe1–Re4 interchange（1.96）, Fe1–Re1interchange（1.87）, and the mechanisms of the saturation magnetization reduction have been analyzed.

关键词： double perovskite imperfections electronic properties magnetic properties