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自治分段线性振荡系统的离散映射数值建模与稳定性分析

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自动化学报 2007年第1期33卷 72-77页

作者：戴欣黄席樾孙跃重庆大学自动化学院重庆400044

为研究自治分段线性振荡系统中出现的分叉及混沌动力学行为,系统建模及稳定性分析是一种必不可少的分析手段.本文通过构造周期内离散映射解析模型,并结合边界条件的动态数值求解,提出了一种动态离散映射数值建模方法,进而推导了用以判... 详细信息

为研究自治分段线性振荡系统中出现的分叉及混沌动力学行为,系统建模及稳定性分析是一种必不可少的分析手段.本文通过构造周期内离散映射解析模型,并结合边界条件的动态数值求解,提出了一种动态离散映射数值建模方法,进而推导了用以判定系统周期闭轨稳定性的Jacobian矩阵求解模型.最后,本文以电力电子系统中一种常用的5维软开关逆变自治振荡电路作为实例,通过模型仿真观察到频率的分叉现象,并根据Jacobian矩阵的特征乘数对系统的稳定性进行了研究.基于该模型的仿真分析结果与实验系统中所观察到的现象一致,从而验证了该方法的有效性.

关键词：自治分段离散映射建模频率分叉

Structure and immunomodulatory activity of Lentinus edodes polysaccharides modified by probiotic fermentation

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Food Science and Human Wellness 2024年第1期13卷 421-433页

作者： Jingjing Liang Meina Zhang xiaohan Li Yuan yue xiaowei Wang Mengzhen Han Tianli yue Zhouli Wang Zhenpeng Gao College of Food Science and Engineering Northwest A&F UniversityYangling 712100China xi'an Gaoxin No.1 High School Xi'an 710065China

Plant-based fermentations provide an untapped source for novel biotechnological *** this study,a probiotic named Lactobacillus fermentum 21828 was introduced to ferment Lentinus *** were extracted from fermented and non-fermented *** and purified via DEAE-52 and Sephadex *** components designated F-LEP-2a and NF-LEP-2a were analyzed by FT-IR,HPGPC,HPAEC,SEM,GC-MS and *** results revealed that probiotic fermentation increased the molecular weight from 1.16×10^(4) Da to 1.87×10^(4) Da and altered the proportions of glucose,galactose and mannose,in which glucose increased from 45.94%to 48.16%.Methylation analysis and NMR spectra indicated that F-LEP-2a and NF-LEP-2a had similar linkage ***,their immunomodulatory activities were evaluated with immunosuppressive ***-LEP and F-LEP improved immune organ indices,immunoglobulin(Ig G and Ig M)and cytokines concentrations;restored the antioxidation capacity of liver;and maintained the balance of gut microbiota.F-LEP displayed better moderating effects on the spleen index,immunoglobulin,cytokines and the diversity of gut microbiota than NF-LEP(200,400 mg/kg).Our study provides an efficient and environment-friendly way for the structural modification of polysaccharides,which helps to enhance their biological activity and promote their wide application in food,medicine and other fields.

关键词： Lentinus edodes polysaccharide Lactobacillus fermentum fermentation Structural analysis Immunoregulatory activity Nuclear magnetic resonance

Asymmetric Electrolytes Design for Aqueous Multivalent Metal Ion Batteries

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Nano-Micro Letters 2024年第3期16卷 227-253页

作者： xiaochen Yang xinyu Wang yue xiang Longtao Ma Wei Huang Frontiers Science Center for Flexible Electronics Institute of Flexible ElectronicsNorthwestern Polytechnical UniversityXi’an 710072People’s Republic of China School of Materials Science and Engineering Guangdong Provincial Key Laboratory of Advanced Energy Storage MaterialsSouth China University of TechnologyGuangzhou 510641People’s Republic of China

With the rapid development of portable electronics and electric road vehicles,high-energy-density batteries have been becoming front-burner ***,homogeneous electrolyte cannot simultaneously meet diametrically opposed demands of high-potential cathode and low-potential anode,which are essential for high-voltage ***,homogeneous electrolyte is difficult to achieve bi-or multi-functions to meet different requirements of *** comparison,the asymmetric electrolyte with bi-or multi-layer disparate components can satisfy distinct requirements by playing different roles of each electrolyte layer and meanwhile compensates weakness of individual ***,the asymmetric electrolyte can not only suppress by-product sedimentation and continuous electrolyte decomposition at the anode while preserving active substances at the cathode for high-voltage batteries with long cyclic *** this review,we comprehensively divide asymmetric electrolytes into three categories:decoupled liquid-state electrolytes,bi-phase solid/liquid electrolytes and decoupled asymmetric solid-state *** design principles,reaction mechanism and mutual compatibility are also studied,***,we provide a comprehensive vision for the simplification of structure to reduce costs and increase device energy density,and the optimization of solvation structure at anolyte/catholyte interface to realize fast ion transport kinetics.

关键词： Asymmetric electrolyte Aqueous multivalent metal ion batteries Electrochemical stability windows Electrolyte interface

CMIP6模式对中国西南地区气温的模拟与预估

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中国农业气象 2022年第8期43卷 597-611页

作者：晋程绣姜超张曦月北京林业大学生态与自然保护学院北京100083

应用1961-2014年CN05.1月平均气温观测数据集,以及国际耦合模式比较计划第六阶段(CMIP6)的19个全球气候模式数据,基于泰勒图、泰勒指数和年际变化技巧评分,系统评估了CMIP6模式对中国西南地区气温的气候态空间分布以及年际变化的模拟能... 详细信息

应用1961-2014年CN05.1月平均气温观测数据集,以及国际耦合模式比较计划第六阶段(CMIP6)的19个全球气候模式数据,基于泰勒图、泰勒指数和年际变化技巧评分,系统评估了CMIP6模式对中国西南地区气温的气候态空间分布以及年际变化的模拟能力,并预估该地区未来气温在SSP1-2.6、SSP2-4.5、SSP3-7.0和SSP5-8.5情景下的变化特点。结果表明:(1)与其他季节相比,大多数CMIP6模式对研究区1961-2014年秋季气温气候态空间分布的模拟表现最好;CMIP6模式模拟四季和年平均气温年际变化的结果整体偏低。19个模式中对西南地区气温模拟较好的模式有ACCESS-CM2、 CMCC-CM2-SR5和CMCC-ESM5。(2)3个较优模式的等权重集合,在模拟气温的气候态空间分布和年际变化方面优于19个模式的等权重集合。(3)与1961-2014年同期观测结果的多年平均气温相比,未来西南地区四季及年平均气温在4种情景下均呈升高趋势,四季和年平均气温升高0.94~3.48℃。4种气候情景下均表现为夏季升温最多(2.17~3.48℃),且夏季平均气温的年际波动幅度最小;冬季升温最少(0.94~2.24℃),其年际波动幅度最大。(4)在21世纪初,4种情景间季节和年平均气温的升高趋势差异不大,随着时间的推移,到21世纪中期,高辐射强迫情景下气温的升高趋势逐渐高于低辐射强迫情景。(5)在4种情景下,21世纪初期(2015-2034年)、中期(2045-2064年)及末期(2081-2100年)的多年平均气温与历史(1961-2014年)观测气温的距平值均呈现西北大于东南、高纬度高海拔地区大于低纬度低海拔地区的空间分布特点。随着时间推移,在21世纪末期,同一地区高辐射强迫情景的气温距平值明显高于低辐射强迫情景。

关键词： CMIP6模式西南地区气温变化评估预估

钢框架梁柱节点在强震作用下的损伤性能研究（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2017年第11期18卷 910-926页

作者： xi-yue LIU Yuan-qing WANG Jun xiONG Yong-jiu SHI College of Basic Education for Commanding Officers National University of Defense Technology Key Laboratory of Civil Engineering Safety and Durability of China Education Ministry Department of Civil EngineeringTsinghua University Nanjing Jianye District Bureau of Construction and Transport

目的:钢框架焊接梁柱节点在地震作用下往往容易产生脆性裂纹,裂纹的发展和损伤累积将导致节点延性降低,发生脆性断裂。本文旨在探究节点在地震往复荷载作用下的损伤性能,分析其主要影响因素,提出有效的损伤评估模型,为后续节点损伤数值... 详细信息

目的:钢框架焊接梁柱节点在地震作用下往往容易产生脆性裂纹,裂纹的发展和损伤累积将导致节点延性降低,发生脆性断裂。本文旨在探究节点在地震往复荷载作用下的损伤性能,分析其主要影响因素,提出有效的损伤评估模型,为后续节点损伤数值模拟提供基础,为钢框架的抗震设计提供参考。创新点:1.通过足尺节点试验,分析加载幅值、加载历程和荷载峰值对节点损伤性能的影响;2.基于试验结果,标定并验证3种经验损伤演化模型,提出基于疲劳断裂力学的节点损伤评估模型。方法:1.通过对9个足尺梁柱节点试件开展往复加载试验,包括5种变幅加载制度及4种常幅加载制度,分析加载幅值、加载历程和荷载峰值对节点损伤性能的影响;2.基于试验结果,根据节点损伤特点,在能量模型基础上,推导并拟合适用于节点循环加载的双参数损伤演化方程,并与其他模型进行比较,以验证其准确性;3.结合疲劳和延性断裂理论,依据损伤机理,定义"有效塑性应变"量化损伤过程,并以疲劳裂纹发展公式为基础,推导适用于计算在极低周循环荷载下节点损伤过程的损伤演化方程。结论:1.加载跨幅对节点性能影响较小;加载历程的影响与历程中峰值位移循环次数密切相关;突发性的强峰值对节点造成的损伤最大。2.节点损伤过程为幂函数形式;通过比较表明,在能量模型基础上推导出的适用于节点循环加载的双参数损伤演化方程,相对于单参数线性模型,能够更准确模拟节点在极低周循环下的损伤过程。3.基于疲劳断裂力学理论的损伤演化方程物理意义明确,能够描述节点循环损伤试验中所表现出的加速损伤及"损伤拐点"特征。

关键词：梁柱节点往复荷载节点试验损伤机理延性断裂

Exosomal miR-29b found in aqueous humour mediates calcium signaling in diabetic patients with cataract

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International Journal of Ophthalmology(English edition) 2021年第10期14卷 1484-1491页

作者： Chao Gao xin Liu Fan Fan Jia-Ning Yang xi-yue Zhou Heng-Jun Mei xiao-Lei Lin Yi Luo First Affiliated Hospital School of MedicineShihezi UniversityShihezi 832000Xinjiang Uygur Autonomous RegionChina Eye Institute Eye and ENT HospitalCollege of MedicineFudan UniversityShanghai 200031China State Key Laboratory of Medical Neurobiology Institutes of Brain Science and Collaborative Innovation Center for Brain ScienceShanghai Medical CollegeFudan UniversityShanghai 200031China Shanghai Key Laboratory of Visual Impairment and Restoration Science and Technology Commission of Shanghai MunicipalityShanghai 200031China Key Laboratory of Myopia(Fudan University) Chinese Academy of Medical SciencesNational Health CommissionShanghai 200031China

AIM:To investigate the role of exosomal miR-29b and Ca^(2+)in regulating the function of human lens epithelial cells(HLECs).METHODS:Exosomes were isolated from human aqueous humour(AH)by ultracentrifugation,and visualized by nanopar ticle tracking and transmission electron *** miRNA sequencing was performed to identify differentially expressed miRNAs between diabetes with cataracts(DMC)group and age-related cataracts(ARC)*** was used to predict potential target of certain *** expression of CACNA1C mRNA was determined by quantitative real-time polymerase chain reaction and CACNA1C protein was determined by Western *** of Ca^(2+)in human AH and the culture supernatant of cells were detected by the calcium assay *** counting kit-8 was used to determine cell ***:Exosomes were isolated from human AH,which had a typical cup-shaped phenotype and a particle size distribution in accordance with micro extracellular *** miRNA sequencing revealed that miR-29b was significantly downregulated in DMC group compared with ***^(2+)concentration of human AH in DMC was higher than that in *** culture supernatant of cells transfected with miR-29b inhibitors had a higher concentration of Ca^(2+)than that transfected with miR-29b ***-29b reduced the viability of HLECs by upregulating CACNA1C ***:Exosomes isolated from human AH contains abundant miRNAs.A significantly expressed miR NA,miR-29b,can affect the concentration of Ca^(2+)and regulate HLEC processes by upregulating CACNA1C.

关键词： exosomes miR-29b diabetes and cataracts Ca^(2+) CACNA1C

隐私显著性与互联网定向广告规避行为的非线性关系研究——基于感知威胁的中介作用

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南开管理评论 2023年第3期26卷 135-145,I0024,I0025页

作者：王烨娣席悦蒋玉石西南交通大学经济管理学院

目前互联网定向广告推送平台对于消费者隐私问题的突出程度各不相同,由此给消费者带来了不同程度的威胁感,进而影响消费者对互联网定向广告的规避行为。基于技术威胁规避理论(TTAT)和应对行为理论(CBT),本研究通过三个实验发现:(1)随着... 详细信息

目前互联网定向广告推送平台对于消费者隐私问题的突出程度各不相同,由此给消费者带来了不同程度的威胁感,进而影响消费者对互联网定向广告的规避行为。基于技术威胁规避理论(TTAT)和应对行为理论(CBT),本研究通过三个实验发现:(1)随着隐私显著性的提高,广告规避行为呈U型变化趋势。即当隐私显著性为中等水平时,广告规避行为最低。(2)感知威胁在隐私显著性与广告规避行为的非线性关系间起部分中介作用。(3)尽管过低或过高的隐私显著性均能引起较高的广告规避行为,但是由于二者诱发原因不同,其应对方法也存在差异。具体而言,低隐私显著性与情绪焦点应对匹配,高隐私显著性与问题焦点应对匹配时,更有助于降低广告规避行为。研究结论为不同隐私显著性的互联网定向广告推送平台提供了不同的解决措施。

关键词：互联网定向广告隐私显著性感知威胁问题焦点应对情绪焦点应对

Effects of surface energy and substrate on modulus determination of biological films by conical indentation

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Science China(Technological Sciences) 2024年第6期67卷 1757-1764页

作者： DING yue LI Cheng-Ya NIU xinRui WANG Gang-Feng Department of Engineering Mechanics SVLXi’an Jiaotong UniversityXi’an710049China Department of Mechanical Engineering City University of Hong KongHong Kong SAR999077China

Micro-/nano-indentation has become prevalent in evaluating the mechanical characteristics of biological samples,such as cells and ***,the existing contact models describing conical indentation ignore the joint effects of surface energy and substrate,and consequently cannot accurately extract the Young's modulus of biological samples deposited on *** finite element methods,we examine the conical indentation of biological films on substrates while taking surface energy into *** on the dimensional analysis,the explicit relationship between load and indentation depth is achieved for films with their moduli varying from 0.001 to 100 times that of the *** the classical Sneddon's model was employed to analyze the load-depth data,the measured modulus could reach 18 times the real modulus for films on harder substrates,but only 4%of the real modulus for films on softer ***,in micro-/nano-indentations,neglecting the contribution of surface energy would result in an overestimation of the Young's modulus of films depending on the contact *** analytical expression provided here can be utilized to precisely deduce the mechanical characteristics of biological films deposited on substrate from the load and indentation depth data of a conical indentation.

关键词： biological film surface effect substrate effect indentation

疫情背景下研究生专业课程在线教学的探索与实践——以“综合地球物理方法及应用”课程为例

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教育教学论坛 2022年第16期 78-81页

作者：乐友喜中国石油大学〔华东〕地球科学与技术学院山东青岛266580

为应对新冠肺炎疫情对研究生正常教学的影响,各高校启动了在线教学方式。在线教学作为疫情时期的特殊教学方式,保证了高校教学工作的正常进行。以研究生专业课程“综合地球物理方法及应用”在线教学为例,针对课程特点,开展了疫情背景下... 详细信息

为应对新冠肺炎疫情对研究生正常教学的影响,各高校启动了在线教学方式。在线教学作为疫情时期的特殊教学方式,保证了高校教学工作的正常进行。以研究生专业课程“综合地球物理方法及应用”在线教学为例,针对课程特点,开展了疫情背景下的在线教学探索与实践,分析了在线教学过程中存在的问题,通过储层地球物理资料解释教学案例库建设、线上课堂授课方式改革、课程考核评价体系建立等措施,改进教学模式和教学方法,提升教学效果。

关键词：在线教学教学模式新冠肺炎疫情综合地球物理教学平台