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Quasiperiodic photonic crystal fiber[Invited]

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Chinese Optics Letters 2023年第6期21卷 17-35页

作者：刘娥贤刘建军 college of Computer and Information Engineering Central South University of Forestry and TechnologyChangsha 410004China Key Laboratory for Micro/Nano Optoelectronic Devices of Ministry of education&Hunan Provincial Key Laboratory of Low-Dimensional Structural Physics and Devices School of Physics and ElectronicsHunan UniversityChangsha 410082China

In the fields of light manipulation and localization,quasiperiodic photonic crystals,or photonic quasicrystals[PQs],are causing an upsurge in research because of their rotational symmetry and long-range orientation of transverse lattice arrays,as they lack translational *** allows for the optimization of well-established light propagation properties and has introduced new guiding ***,as a class,quasiperiodic photonic crystal fibers,or photonic quasicrystal fibers[PQFs],are considered to add flexibility and richness to the optical properties of fibers and are expected to offer significant potential applications to optical fiber *** this review,the fundamental concept,working mechanisms,and invention history of PQFs are *** progress in optical property improvement and its novel applications in fields such as dispersion control,polarization-maintenance,supercontinuum generation,orbital angular momentum transmission,plasmon-based sensors and filters,and high nonlinearity and topological mode transmission,are then reviewed in ***-type air-guiding PQFs supporting low attenuation propagation and regulation of photonic density states of quasiperiodic cladding and in which light guidance is achieved by coherent Bragg scattering are also ***,current challenges encountered in the guiding mechanisms and practical preparation techniques,as well as the prospects and research trends of PQFs,are also presented.

关键词： photonic quasicrystal fiber guiding mechanism guiding features and applications challenges and prospects

Boosting Plasmonic Hot Electron Utilization for Visible-Light Photocatalysis Using Polarized Ag-TiO_(2) Nanoparticles

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CCS Chemistry 2023年第8期5卷 1908-1916页

作者： Yonglong Li Linfeng Yu Ying Wang Cancan Zhang Yangxuan Gao Teng Wang Wei Xie Key Laboratory of Advanced Energy Materials Chemistry(Ministry of education) Tianjin Key Laboratory of Biosensing and Molecular RecognitionHaihe Laboratory of Sustainable Chemical TransformationsRenewable Energy Conversion and Storage CenterCollege of ChemistryNankai UniversityTianjin 300071

Plasmonic hot electrons have long been regarded as a promising energy source for inducing chemical ***,because of the mismatch between the electron cloud of reactant molecules and the hot-electron gas of metal nanoparticles(NPs),the highly localized and short-lived hot electrons are dif-ficult to utilize in bulk synthesis when the reactant molecules do not have a strong affinity for the metal ***,we propose the concept of polarized nanocatalysts to mimic chemical polarity at the nanometer *** plasmonic photorecycling conditions,the rationally designed asymmetric Ag-TiO_(2) hybrid NPs enable six-electron reduction of molecules in bulk *** hot-electron-driven reaction does not require a conventional hydrogen or hydride reducing *** a proof-of-concept,one-pot photocatalytic syntheses of amides,such as paracetamol,using nitro reactants were *** provides a new opportunity to enable challenging multielectron transformations in organic chemistry.

关键词： plasmonic catalysis polarized nanoparticles hot electrons multielectron transfer amide synthesis

The role of dyadic interactions in the mixed-mating strategies of the mangrove rivulus Kryptolebias marmoratus

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Current Zoology 2010年第1期56卷 6-17页

作者： Kelly N.LUKE David L.BECHLER Division of Natural Sciences Mathematics and Physical Education South Georgia College Department of Biology Valdosta State University

The mangrove rivulus Kryptolebias marmoratus a small cyprinodont fish native to tropical and subtropical watersfrom Florida to Brazil, is one of two known self-fertilizing, hermaphroditic vertebrates of which K. marmoratus displays androdioecy,a complex system of reproduction in which hermaphrodites and males are present. This study describes the behavioralrepertoires observed during dyadic interactions in the laboratory. Kryptolebias marmoratus exhibited 23 distinctive acts or *** were divided into four categories: aggressive, submissive, neutral, and reproductive. Leading and following behaviorsplayed important roles in the behavioral repertoires of these fish. In hermaphrodite-male dyads, males exclusively initiatedthe reproductive process and actively pursued hermaphrodites. When hermaphrodites were paired, there was no evidence that theybehaved like other simultaneous hermaphrodites that alternate sexual roles (e.g. serranids). Hermaphrodites were extremely aggressivetowards one another, and the aggressor established dominance rapidly. Male-male dyads were divided into two subdivisionsbased on the presence or absence of the caudal ocellus on one fish. A caudal ocellus on one male appeared to signal the possibilityof a potential mating partner to males lacking it. Pairings of males without an ocellus were similar to hermaphrodite-hermaphrodite dyads in that both members of the pair were aggressive towards one another. These observations may be indicativeof interactions taking place in natural communities or assemblages of fish in which both males and hermaphrodites occurand provide evidence on the role of dyadic interactions in the mixed-mating

关键词：红树林交配混合

Experimental Study on the Influence of Fracturing Fluid Retention on Shale Gas Diffusion Law

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Energy Engineering 2023年第8期120卷 1853-1866页

作者： Zhiyuan Yao Jing Sun Dehua Liu Cooperative Innovation Center of Unconventional Oil and Gas(Ministry of education&Hubei Province) Yangtze UniversityWuhanChina Petroleum Engineering college Yangtze UniversityWuhanChina Hubei Shale Gas Development Engineering Technology Research Center Yangtze UniversityWuhanChina

Shale gas reservoirs have poor physical properties and a large number of micro-nano pores have been *** gas wells have no natural productivity and need fracturing reconstruction measures to put into ***,the fracturing fluid will enter the reservoir space of shale matrix after fracturing and affect the production of shale *** present,there is no consensus on the influence of fracturing fluid retention on gas well *** on this,the paper adopts gas molecular transport analyzer to carry out experimental research on the influence of fracturing fluid on shale gas diffusion law after entering matrix *** results show that:(1)Compared with the diffusion capacity of single-phase shale gas,the diffusion capacity of shale gas decreases significantly when fracturing fluid is present in the reservoir;(2)In the process of fracturing fluid flowback,when the water saturation in the reservoir decreases from 50%to 0,the gas well productivity increases by about 60%.(3)When fracturing fluid exists in the reservoir,the pore diameter has an exponential relationship with the shale gas diffusion coefficient,and the diffusion coefficient increases exponentially with the increase of pore *** research of this paper provides theoretical basis for guiding the efficient development of shale gas wells.

关键词： Shale gas micro nano pore water saturation diffusion law gas production

Frictional stability of Longmaxi shale gouges and its implication for deep seismic potential in the southeastern Sichuan Basin

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Deep Underground Science and Engineering 2022年第1期1卷 3-14页

作者： Fengshou Zhang Li Cui Mengke An Derek Elsworth Changrong He Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghaiChina Key Laboratory of Geotechnical and Underground Engineering of Ministry of education Tongji UniversityShanghaiChina Department of Energy and Mineral Engineering EMS Energy Institute and G3 CenterThe Pennsylvania State UniversityState CollegePennsylvaniaUSA Department of Geosciences The Pennsylvania State UniversityState CollegePennsylvaniaUSA State Key Laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake AdministrationBeijingChina

Microearthquakes accompanying shale gas recovery highlight the importance of exploring the frictional and stability properties of shale *** to reveal the influencing factors on fault stability,this paper explores the impact of mineral compositions,effective stress and temperature on the frictional stability of Longmaxi shale gouges in deep reservoirs located in the Luzhou area,southeastern Sichuan *** shear experiments were conducted to define the frictional strength and stability of five shale *** specific experimental conditions were as follows:temperatures:90–270°C;a confining stress:95 MPa;and pore fluid pressures:25–55 *** results show that all five shale gouges generally display high frictional strength with friction coefficients ranging from 0.60 to 0.70 at the aforementioned experiment condition of pressures,and *** stability is significantly affected by temperature and mineral compositions,but is insensitive to variation in pore fluid *** instability is enhanced at higher temperatures(especially at>200°C)and with higher tectosilicate/carbonate *** results demonstrate that the combined effect of mineral composition and temperature is particularly important for induced seismicity during hydraulic fracturing in deep shale reservoirs.

关键词： deep shale reservoir hydraulic fracturing hydrothermal condition induced seismicity mineral composition shale fault stability

A Layer-Stripping Method for 3D Near-Surface Velocity Model Building Using Seismic First-Arrival Times

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Journal of Earth Science 2015年第4期26卷 502-507页

作者： Taikun Shi Jianzhong Zhang Zhonglai Huang Changkun Jin college of Marine Geosciences Ocean University of China Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of Education

In order to improve the efficiency of 3D near-surface velocity model building, we develop a layer-stripping method using seismic first-arrival times. The velocity model within a Common Mid-Point （CMP） gather is assumed to be stratified into thin layers, and the velocity of each layer var- ies linearly with depth. The thickness and velocity of the top layer are estimated using minimum-offset first-arrival data in a CMP gather. Then the top layer is stripped and the second layer becomes a new top layer. After removing the effect of the top layer from the former first-arrival data, the new first-arrival data are obtained and then used to estimate the parameters of the second layer. In this manner, the velocity model, being regarded as that at a CMP location, is built layer-by-layer from the top to the bottom. A 3D near-surface velocity model is then formed using the velocity models at all CMP locations. The tests on synthetic and observed seismic data show that the layer-stripping method can be used to build good near-surface velocity models for static correction, and its computation speed is approximately hundred times faster than that of grid tomography.

关键词： first-arrival time layer-stripping near-surface velocity model building static correction.

Response of the North Pacific Storm Track Activity in the Cold Season to Multi-scale Oceanic Variations of Kuroshio Extension System: A Statistical Assessment

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Advances in Atmospheric Sciences 2023年第3期40卷 514-530页

作者： Peilong YU Minghao YANG Chao ZHANG Yi LI Lifeng ZHANG Shiyao CHEN Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment ChangeNanjing University of Information Science and TechnologyNanjing 210044China college of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China

In this paper,a statistical method called Generalized Equilibrium Feedback Analysis(GEFA)is used to investigate the responses of the North Pacific Storm Track(NPST)in the cold season to the multi-scale oceanic variations of the Kuroshio Extension(KE)system,including its large-scale variation,oceanic front meridional shift,and mesoscale eddy *** show that in the cold season from the lower to the upper troposphere,the KE large-scale variation significantly weakens the storm track activity over the central North Pacific south of 30°*** northward shift of the KE front significantly strengthens the storm track activity over the western and central North Pacific south of 40°N,resulting in a southward shift of the *** contrast,the NPST response to KE mesoscale eddy activity is not so significant and relatively shallow,which only shows some significant positive signals near the dateline in the lower and middle ***,it is found that baroclinicity and baroclinic energy conversion play an important role in the formation of the NPST response to the KE multi-scale oceanic variations.

关键词： generalized equilibrium feedback analysis Kuroshio Extension multi-scale oceanic variations North Pacific storm track

Tunneling effect in cavity-resonator-coupled arrays

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Chinese Physics B 2013年第5期22卷 536-539页

作者：马华屈绍波梁昌红张介秋徐卓王甲富 Electronic Materials Research Laboratory Key Laboratory of Ministry of EducationXi'an Jiaotong University The college of Science Air Force University of Engineering The college of Electronic Engineering Xidian University

The quantum tunneling effect （QTE） in a cavity-resonator-coupled （CRC） array was analytically and numerically investigated. The underlying mechanism was interpreted by treating electromagnetic waves as photons, and then was generalized to acoustic waves and matter waves. It is indicated that for the three kinds of waves, the QTE can be excited by cavity resonance in a CRC array, resulting in sub-wavelength transparency through the narrow splits between cavities. This opens up opportunities for designing new types of crystals based on CRC arrays, which may find potential applications such as quantum devices, micro-optic transmission, and acoustic manipulation.

关键词： quantum tunneling effect surface plasmon cavity-resonator photonic crystal

Synthesis, Structure and Luminescent Property of an Europium(Ⅲ) Coordination Polymer

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Chinese Journal of Structural Chemistry 2014年第11期33卷 1649-1654页

作者：叶燕珠林深吴新建 Department of Science Research and Training Fujian Institute of Education college of Chemistry and Chemical Engineering Fujian Normal University

A novel europium（Ⅲ） coordination polymer, [Eu3（pydc）3（SO4）（H2O）5（ox）0.5]·3H2O（1, H2ox = oxalic acid, H2 pydc = pyridine-2,6-dicarboxylic acid）, has been synthesized hydrothermally from the self-assembly of lanthanide ions（Eu3＋） with the flexible oxalic acid and the rigid pyridine-2,6-dicarboxylic acid ligands, respectively. It crystallizes in the triclinic system, space group P1 with a = 11.225（4）, b = 12.390（5）, c = 13.752（5）A, α = 89.228（7）, β = 71.142（6）, γ = 75.552（6）°, Dc = 2.317 g/cm^3, μ = 5.480 mm^-1, F（000） = 1150, Z = 2, the final R = 0.0351 and w R = 0.0949 for 8782 observed reflections with I 〉 2σ（I）. Structural analysis reveals that complex 1 exhibits a three-dimensional metal-organic framework via π-π stacking interactions. In addition, complex 1 displays a red fluorescence emission in the solid state at room temperature, which corresponds to the 5D0 → 7F2 transition of Eu3＋ ions.

关键词： coordination polymer lanthanide luminescent property