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Synchronization within synchronization: transients and intermittency in ecological networks

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National Science Review 2021年第10期8卷 23-32页

作者： huawei fan Ling-Wei Kong Xingang Wang Alan Hastings Ying-Cheng Lai School of Physics and Information Technology Shaanxi Normal University School of Electrical Computer and Energy Engineering Arizona State University Department of Environmental Science and Policy University of California Santa Fe Institute Department of Physics Arizona State University

Transients are fundamental to ecological systems with significant implications to management,conservation and biological control. We uncover a type of transient synchronization behavior in spatial ecological networks whose local dynamics are of the chaotic, predator–prey type. In the parameter regime where there is phase synchronization among all the patches, complete synchronization(i.e. synchronization in both phase and amplitude) can arise in certain pairs of patches as determined by the network symmetry—henceforth the phenomenon of ‘synchronization within synchronization.’ Distinct patterns of complete synchronization coexist but, due to intrinsic instability or noise, each pattern is a transient and there is random, intermittent switching among the patterns in the course of time evolution. The probability distribution of the transient time is found to follow an algebraic scaling law with a divergent average transient lifetime. Based on symmetry considerations, we develop a stability analysis to understand these phenomena. The general principle of symmetry can also be exploited to explain previously discovered,counterintuitive synchronization behaviors in ecological networks.

关键词： ecological networks cluster synchronization phase synchronization transient chaos network symmetry

A high-performance multi-wavelength optical switch based on multiple fano resonances in an all-dielectric metastructure

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Optoelectronics Letters 2024年第4期20卷 193-199页

作者： CAO Shuangshuang fan Xinye fanG Wenjing CHEN huawei BAI Chenglin TONG Cunzhu School of Physics Science and Information Engineering Liaocheng UniversityLiaocheng 252000China Shandong Provincial Key Laboratory of Optical Communication Science and Technology Liaocheng 252000China Liaocheng Key Laboratory of Industrial-Internet Research and Application Liaocheng 252000China Institute of Semiconductors Chinese Academy of SciencesBeijing 100083China State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China

The multi-wavelength optical switch based on an all-dielectric metastructure consisting of four asymmetric semi-circular rings was designed and analyzed in this paper.Four fano resonance modes,which can be explained by bound states in the continuum(BIC)theory,are excited in our structure with a maximum Q-factor of about 2450 and a modulation depth close to 100%.By changing the polarization direction of the incident light,the transmission amplitude of fano resonances can get effectively modulated.Based on this tuning property,the metastructure can achieve a multi-wavelength optical switch in the near-infrared region(900—980 nm)and the maximum extinction ratio can reach 38.3 d B.In addition,the results indicate that the fano resonances are sensitive to the changes in the refractive index.The sensitivity(S)and the figure of merit(FOM)are 197 nm/RIU and 492 RIU-1.The proposed metastructure has promising potential in applications such as optical switches,sensors,modulators and lasers.

关键词： dielectric structure resonance

Chaos synchronization with dual-channel time-delayed couplings

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Science China(Technological Sciences) 2016年第3期59卷 428-435页

作者： fan huawei WANG YaFeng CHEN MengJiao WANG XinGang School of Physics and Information Technology Shaanxi Normal University Institute of Theoretical & Computational Physics Shaanxi Normal University

While the significance of oscillator dynamics and coupling structure to synchronization behaviors has been well addressed in the literature, little attention has been paid to the possible influence of coupling functions. In the present paper, adopting the scheme of dual-channel time-delayed couplings, we investigate how the synchronization behaviors of networked chaotic oscillators are influenced by parameters in the coupling functions. It is found that, with the introduction of the second coupling channel, the synchronization region, as calculated according to the method of master stability function(MSF), can be largely modified. In particular, by a slight change of the time delay, it is found that the synchronization region can be significantly adjusted, or even switched from non-existing to existing. We demonstrate this interesting phenomenon for both situations of processing and propagation induced time delays, as well as for different coupling functions. Our studies shed new light on the mechanism of chaos synchronization, and may potentially be used for the control of complex network dynamics.

关键词：混沌同步耦合结构传输延时双通道网络动力学可能影响函数参数混沌振荡

High-silica faujasite zeolite-tailored metal encapsulation for the low-temperature production of pentanoic biofuels

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Journal of Energy Chemistry 2024年第1期88卷 552-560,I0012页

作者： Wenhao Cui Yuanshuai Liu Pengfei Guo Zhijie Wu Liqun Kang huawei Geng Shengqi Chu Linying Wang Dong fan Zhenghao Jia Haifeng Qi Wenhao Luo Peng Tian Zhongmin Liu National Engineering Research Center of Lower-Carbon Catalysis Technology Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China Qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of SciencesQingdao 266101ShandongChina College of Chemistry and Chemical Engineering Inner Mongolia UniversityHohhot 010021Inner MongoliaChina State Key Laboratory of Heavy Oil Processing and Key Laboratory of Catalysis of CNPC China University of PetroleumBeijing 102249China Department of Inorganic Spectroscopy Max Planck Institute for Chemical Energy ConversionMülheim an der Ruhr 45470Germany Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Division of Energy Research Resources Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina Leibniz-Institut für Katalyse Albert-Einstein-Straβe 29aRostock 18059Germany

Zeolite-encapsulated metal nanoclusters are at the heart of bifunctional catalysts,which hold great potential for petrochemical conversion and the emerging sustainable biorefineries.Nevertheless,efficient encapsulation of metal nanoclusters into a high-silica zeolite Y in particular with good structural integrity still remains a significant challenge.Herein,we have constructed Ru nanoclusters(~1 nm)encapsulated inside a high-silica zeolite Y(SY)with a SiO_(2)/Al_(2)O_(3) ratio(SAR)of 10 via a cooperative strategy for direct zeolite synthesis and a consecutive impregnation for metal encapsulation.Compared with the benchmark Ru/H-USY and other analogues,the as-prepared Ru/H-SY markedly boosts the yields of pentanoic biofuels and stability in the direct hydrodeoxygenation of biomass-derived levulinate even at a mild temperature of 180℃,which are attributed to the notable stabilization of transition states by the enhanced acid accessibility and properly sized constraints of zeolite cavities owing to the good structural integrity.

关键词： High-silica zeolite Y Metal encapsulation Bifunctional catalysis Hydrodeoxygenation Biofuels

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“热点述评”教学法融入高校思政课探析

淮北职业技术学院学报 2023年第4期22卷 59-62页

作者：范华伟阜阳职业技术学院马克思主义学院安徽阜阳236031

学生对待社会热点的看法和态度直接反映其思想动态,为开展思想政治教育活动提供了重要的载体和契机。“热点述评”教学法利用实践教学活动,观察和回应现实焦点问题,有利于发挥大学生主体作用,调动其学习积极性和主动性。“热点述评”教... 详细信息

学生对待社会热点的看法和态度直接反映其思想动态,为开展思想政治教育活动提供了重要的载体和契机。“热点述评”教学法利用实践教学活动,观察和回应现实焦点问题,有利于发挥大学生主体作用,调动其学习积极性和主动性。“热点述评”教学法融入高校思政课教学改革,有利于思政课教师业务素养和思政课教学质量的提高。

关键词：热点述评思政课价值诉求组织实施

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危险源识别及评价工作要点

化工设计 2023年第3期33卷 48-50,2页

作者：樊华伟中国五环工程有限公司武汉430074

本文列出危险源识别及评价工作的要点,介绍危险源的种类、识别方法、评价方法,并结合实例进一步阐述方法的应用,对掌握危险源识别及评价工作有很强的指导作用。

关键词：危险源识别危险源评价

基于mRNA疫苗产品生产技术探讨监管检查关注要点

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中国药事 2022年第1期36卷 16-24页

作者：韩彬樊华伟曹萌上海药品审评核查中心上海201203

目的:探讨提升商业化mRNA疫苗生产质量水平以降低风险、提升获益,确保疫苗生产过程符合法规要求,并推进监管领域相关标准、技术指南的完善。方法:通过分析mRNA疫苗生产技术特点,梳理mRNA疫苗产品各个生产环节中的质量风险点,综述相关领... 详细信息

目的:探讨提升商业化mRNA疫苗生产质量水平以降低风险、提升获益,确保疫苗生产过程符合法规要求,并推进监管领域相关标准、技术指南的完善。方法:通过分析mRNA疫苗生产技术特点,梳理mRNA疫苗产品各个生产环节中的质量风险点,综述相关领域研究进展,并探讨mRNA疫苗生产现场监管检查的一些要点。结果与结论:mRNA疫苗生产一般包括转录模板制备、原液生产、制剂生产和灌装等步骤,其中产生抗原作用的mRNA分子一般采用体外表达系统,制剂生产一般采用脂质纳米颗粒(LNP)技术。基于mRNA疫苗产品的固有风险、特定生产要求和工艺特征,明确应关注DNA模板的制备、场地设施条件、对RNA酶的控制、工艺杂质控制能力及质量保证程度、LNP生产稳健性、储运低温与防震能力、委托检验管理等方面的现场情况。建议尽快制定相关标准、指南细则,以包容审慎的态度在保证质量的前提下推进mRNA产业发展,提升疫苗生产全链条质量保证水平。

关键词：信使核糖核酸新冠疫苗生产药品生产质量管理规范监管

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郑州市国土空间生态修复的关键区域识别

水土保持通报 2024年第2期44卷 267-276页

作者：樊凡田国行刘贺王赫李华威河南农业大学风景园林与艺术学院河南郑州450002 郑州市规划勘测设计研究院河南郑州450052

[目的]对郑州市国土空间生态修复关键区域识别,为该市和市域国土空间生态修复规划提供科学参考。[方法]利用形态学空间格局分析(MSPA)识别生态源地,通过景观连通性评价与电路理论提取生态廊道、识别生态修复关键区域,最终构建生态网络... 详细信息

[目的]对郑州市国土空间生态修复关键区域识别,为该市和市域国土空间生态修复规划提供科学参考。[方法]利用形态学空间格局分析(MSPA)识别生态源地,通过景观连通性评价与电路理论提取生态廊道、识别生态修复关键区域,最终构建生态网络安全格局。[结果]郑州市生态源地共37个,面积共计983.29 km^(2),呈现西多东少,南北呈带状聚拢分布;提取郑州市85条生态廊道,廊道长度为0.11~47.92 km,共计689.50 km,其中关键生态廊道19条、重要生态廊道29条、一般生态廊道37条;识别生态夹点55处,总面积2.78 km^(2),多集于郑州市西南部,夹点所处位置阻力较小,土地类型主要以林地、草地、水体为主;将累计电流值划分3种等级障碍点,总面积为1054.31 km^(2),占研究区面积的14.16%,主要位置在登封市与新密市主要交通道路周围的城镇区域;综合考虑研究区自然与社会现状,提出“一带,一环,两区,四团,多点”的生态网络安全格局。[结论]对识别的生态夹点与障碍点分别提出修复策略:生态夹点区域生态环境较好,因此以自然生态维护为主;生态障碍点区域主要为建设用地,开发强度较大,受人类干扰程度较多,因此以人工和自然修复并重的方式为主。

关键词：电路理论生态网络构建国土空间生态修复关键区域识别郑州市

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高油价下中国LPG行业形势及应对策略

当代石油石化 2005年第11期13卷 31-33,44页

作者：范华伟上海沥青销售分公司上海200050

分析了高油价时期我国液化石油气市场的新特点,并提出了应对新形势的策略。

关键词：中国液化石油气市场策略