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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

Effects of NO_x and VOCs from Five Emission Sources on Summer Surface O_3 over the Beijing–Tianjin–Hebei Region

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Advances in Atmospheric Sciences 2014年第4期31卷 787-800页

作者： QU Yu AN Junling LI Jian CHEN Yong LI ying LIU xingang HU Min State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal University State Key Joint Laboratory of Environment Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University

The impacts of emissions from industry,power plant,transportation,residential,and biogenic sources on daily maximum surface ozone （O3DM） over the Beijing-Tianjin-Hebei （BTH） region in North China in the summer of 2007 were examined in a modeling *** modeling system consisted of the Weather Research and Forecasting （WRF） model and the photochemical dispersion model,*** factor separation technique （FST） was used to quantify the effect of individual emission source types and the synergistic interactions among two or more ***,the effectiveness of emission reduction scenarios was *** industry,power plant,and transportation emission source types were found to be the most important in terms of their individual effects on *** key contributor to high surface O3 was power plant emissions,with a peak individual effect of 40 ppbv in the southwestern BTH *** individual effect from the biogenic emission category was quite *** synergistic effects from the combinations of each pair of anthropogenic emission types suppressed O3 formation,while the synergistic effects for combinations of three were favorable for O3 formation when the industrial and power plant emission source types *** quadruple synergistic effects were positive only with the combination of power plant,transportation,residential,and biogenic sources,while the quintuple synergistic effect showed only minor impacts on O3DM concentrations.A 30％ reduction in industrial and transportation sources produced the most effective impacts on O3 concentrations,with a maximum decrease of 20 *** results suggested that the synergistic impacts among emission source types should be considered when formulating emission control strategies for O3 reduction.

关键词： O3 CAMx model synergistic effect factor separation technique emission source

新时代背景下黄炎培职业教育思想对高职院校办学的启示

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职业技术 2025年第1期24卷 25-31页

作者：沈璐胡新岗朱善元李莹黄银云江苏农牧科技职业学院江苏泰州225300

作为我国职业教育的奠基人,黄炎培先生在曲折的实践、艰难的探索中,形成了对我国职业教育发展至关重要的思想理论体系,至今对我国高职院校的高水平建设和高质量发展仍具有重要的指导意义。在国家“双高计划”建设背景下,高职院校应围绕... 详细信息

作为我国职业教育的奠基人,黄炎培先生在曲折的实践、艰难的探索中,形成了对我国职业教育发展至关重要的思想理论体系,至今对我国高职院校的高水平建设和高质量发展仍具有重要的指导意义。在国家“双高计划”建设背景下,高职院校应围绕“人才培养质量高”“产教融合水平高”两个关键办学要求,秉承以人为本、为社会服务、做学合一、能力导向的原则,提升内部治理水平,从优化专业设置和布局、深化产教融合机制创新、强化师资队伍建设等方面推进教育教学高水平建设,服务教育强国战略和技能型社会建设,促进我国职业教育高质量发展。

关键词：黄炎培职业教育思想高职院校高质量发展启示

Palladium Difluorocarbene Involved Catalytic Coupling with Terminal Alkynes

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CCS Chemistry 2020年第5期2卷 293-304页

作者： Xue-ying Zhang Xia-Ping Fu Shu Zhang xingang Zhang Key Laboratory of Organofluorine Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032(China) College of Chemistry Henan Institute of Advanced TechnologyZhengzhou UniversityZhengzhou 450001(China) School of Materials and Energy University of Electronic Science and Technology of ChinaChengduSichuan 611731(China)

Difluoromethylated alkynes are a versatile synthon for the diversity-oriented synthesis of difluoromethyl compounds that are of great interest in life and materials ***,the catalytic cross-coupling for the synthesis of difluoromethylated alkynes remains challenging,despite impressive achievements made in the cross-coupling reactions for alkynes,including the Sonogashira ***,we report a palladium difluorocarbene involvement in catalytic coupling with terminal alkynes,representing a new mode of conjugation reaction,which circumvents the radical pathway usually encountered during the coupling of alkynes with fluoroalkyl *** reaction uses inexpensive and abundant industrial raw material chlorodifluoromethane(ClCF_(2)H)as the difluorocarbene precursor,and features cost-effectiveness,excellent functional group tolerance,and broad substrate scope,including synthesis of drug-like complex *** mechanistic studies showed a unique catalytic pathway of this process,in which additive hydroquinone plays a pivotal role in promoting the reaction.

关键词： Alkynes cross-coupling difluorocarbene difluoromethyl palladium

Design and anti-sway performance testing of pesticide tanks in spraying UAVs

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International Journal of Agricultural and Biological Engineering 2019年第1期12卷 10-16页

作者： Yu Zang ying Zang Zhiyan Zhou Xiuyan Gu Rui Jiang Lingxi Kong xingang He Xiwen Luo Yubin Lan College of Engineering South China Agricultural University/Guangdong Engineering Research Center for Agricultural Aviation Application(ERCAAA)Guangzhou 510642China National Joint Research Center for Precision Agricultural Aviation Application Technology Guangzhou 510642China Key Laboratory of Key Technology on Agricultural Machine and Equipment(South China Agricultural University) Ministry of EducationGuangzhou 510642China

Anti-sway performance is one of the most important factors that affect the stability of unmanned aerial vehicles(UAVs).In this study,an anti-sway performance testing method and an evaluation formula for pesticide tanks were developed,which could facilitate the design and application of pesticide *** detection device mainly comprises a testing stand,a mounting and testing part,and a driving and control *** the testing method,P(maximum pressure)measured by a barometer and t(fluctuation recovery time)measured by a high-speed camera were used as evaluation *** the aim to determine the optimal position of the pressure detection device and the optimal filling ratio,four representative pesticide tanks were involved in this *** results showed that the optimal position of the pressure detection device was at the middle position on the tank wall,halfway up from the bottom,and the optimal filling ratio was *** P and t as evaluation indexes,a comprehensive evaluation formula was developed based on these tests:S=0.7Pi+***-sway performance of pesticide tanks was evaluated by a comprehensive score.A disk pesticide tank with a baffle was determined to be the best among the four types of pesticide tanks,showing a score of *** scores of the other three pesticide tanks were 0.500,0.428 and 0.612,*** results indicated that the baffle structure in the pesticide tank and the radian design of the tank wall can effectively improve the anti-sway performance of a pesticide *** proposed detection device and test method are simpler and more intuitive compared to other approaches in evaluating the anti-sway performance of pesticide tanks in spraying UAVs,and they can be used as a reference to guide the design of pesticide tanks and the stability evaluation of spraying UAVs.

关键词： spraying UAV pesticide tank liquid sloshing anti-sway performance test detection method

重大突发公共卫生事件中社会群体行为演化的计算实验:以新冠疫情为例

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中国管理科学 2024年第5期32卷 207-217页

作者：赵新刚周颖华北电力大学经济与管理学院北京102206 新能源电力与低碳发展研究北京市重点实验室北京102206

科学认识重大突发公共卫生事件中的社会群体行为及其演化,是当前我国全面提高政府社会治理能力的关键途径。本文以新冠疫情为例,在刻画不同社会群体的状态、行为及演化规则基础上,构建了群体行为演化的元胞自动机模型并据此进行了计算... 详细信息

科学认识重大突发公共卫生事件中的社会群体行为及其演化,是当前我国全面提高政府社会治理能力的关键途径。本文以新冠疫情为例,在刻画不同社会群体的状态、行为及演化规则基础上,构建了群体行为演化的元胞自动机模型并据此进行了计算实验。结果表明:新冠病毒传播中,初始感染率、传染率和舆情对社会群体行为的演化存在较为显著的影响,而潜伏期的影响并不显著;科学降低初始感染率和传染率,有效进行社会舆情治理,以促使社会个体采取正行为并引导社会群体行为向正行为演化,能有效降低新冠病毒的感染率,反之反是。因此,科学引导社会群体行为并强化政府的社会治理能力,是当前有效控制新冠疫情扩散的重要途径。

关键词：新冠疫情群体行为演化社会治理计算实验

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蒸馏过程强化技术研究进展

化工进展 2018年第4期37卷 1212-1228页

作者：李洪孟莹李鑫钢高鑫天津大学化工学院天津300350 精馏技术国家工程研究中心天津300350 天津化学化工协同创新中心天津300350

蒸馏过程强化技术作为我国现代化学工业发展的重要研究领域,是过程强化概念在化学工业成功应用的典范之一。随着近些年的发展,蒸馏过程强化技术的研究已形成了一套较完整的体系,但也出现了一系列新的难题与挑战。为此,本文针对混合物相... 详细信息

蒸馏过程强化技术作为我国现代化学工业发展的重要研究领域,是过程强化概念在化学工业成功应用的典范之一。随着近些年的发展,蒸馏过程强化技术的研究已形成了一套较完整的体系,但也出现了一系列新的难题与挑战。为此,本文针对混合物相对挥发度与气液传质两个蒸馏过程强化的基础理论本质问题,以基础理论创新、关键技术突破和关键装备研究进展为主线,从强化原理、研究进展、工业应用及发展3方面系统介绍共沸蒸馏、萃取蒸馏、反应蒸馏这3类典型的引入质量分离剂强化的蒸馏过程及其耦合技术;微波、超重力场等典型外场作用下的引入能量分离剂强化的蒸馏过程,并系统介绍以新型塔内件及新型塔结构为切入点的基于先进设备强化的蒸馏过程,为迎接这一领域新的难题和挑战提供新思路。

关键词：蒸馏过程强化蒸馏化工过程强化相对挥发度强化气液传质强化

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泰安市介入放射学应用现状调查分析

中华放射医学与防护杂志 2019年第12期39卷 936-939页

作者：王英毛新刚邱静泰安市疾病预防控制中心辐射防护安全监测评价科 271000

介入放射学已经迅速发展成为现代医学所不可或缺的诊断与治疗手段,但由于介入放射诊疗程序需较长时间的曝光,操作者必须在诊视床旁边长时间暴露在X射线下近台操作,导致介入放射学工作人员和患者接受的辐射剂量相对较大。随着适应证的越... 详细信息

介入放射学已经迅速发展成为现代医学所不可或缺的诊断与治疗手段,但由于介入放射诊疗程序需较长时间的曝光,操作者必须在诊视床旁边长时间暴露在X射线下近台操作,导致介入放射学工作人员和患者接受的辐射剂量相对较大。随着适应证的越来越广泛,进行介入放射学诊疗的工作人员和患者成为一个接受较高辐射剂量的人群,引起了国际放射防护界的广泛关注。

关键词：介入放射学辐射剂量放射防护现代医学介入放射诊疗现状调查分析 X射线泰安市

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海洋平台电力系统谐波分析及仿真研究

石油机械 2006年第12期34卷 10-13页

作者：余颖王新刚中国海洋石油工程股份有限公司设计公司防灾科技学院

针对海上油气田日益严重的谐波污染问题,对海上平台电力系统的谐波进行了研究,概述了海上平台电力系统谐波污染的原因和特点。通过EDSA电力系统分析仿真软件对西江23-1油田电力系统进行谐波分析,并根据仿真结果提出可行的滤波方案。仿... 详细信息

针对海上油气田日益严重的谐波污染问题,对海上平台电力系统的谐波进行了研究,概述了海上平台电力系统谐波污染的原因和特点。通过EDSA电力系统分析仿真软件对西江23-1油田电力系统进行谐波分析,并根据仿真结果提出可行的滤波方案。仿真实验表明,钻井平台变频器的广泛应用将产生严重的谐波污染,应采取相应措施进行抑制;而仿真软件是进行谐波分析并确定滤波方案的有效手段。

关键词：谐波分析海洋平台电力系统 EDSA软件仿真实验