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Effect of Interfacial Strength on the Flexural Behavior of Glass Fiber Reinforced Polymer(GFRP) Reinforced Concrete Beam

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Journal of Wuhan University of Technology(Materials Science) 2015年第5期30卷 1001-1007页

作者：张亚芳 YANG Wenlong LIU Hao chen peiran LIU Feng Faculty of Civil Engineering Guangzhou University

The reinforcement/matrix interfacial strength has been considered as the key factor when glass fiber reinforced polymer(GFRP) bar is mixed with concrete. In this paper, based on micromechanics, fourpoint bending numerical models with and without glass fiber of different interfacial strength have been set up to simulate the damage process of GFRP reinforced concrete beam. The results show that the higher the interfacial strength is, the higher the ultimate bearing capacity of beams, and the less the opening width and height of cracks will be reached. Furthermore, mixing of glass fibers has less influence on the damage process when the interfacial strength is weak, however, it can help to improve the ultimate bearing capacity of the beams, retard the expansion of cracks and improve the toughness when the interfacial strength is high.

关键词： interfacial strength GFRP damage process debonding numerical simulation

Spatial pattern and developing mechanism of railway geo-systems based on track gauge:A case study of Eurasia

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Journal of Geographical Sciences 2020年第8期30卷 1283-1306页

作者： WANG chengjin LI Xumao chen peiran XIE Yongshun LIU Weidong Institute of Geographic Sciences and Natural Resources Research CASBeijing 100101China Key Laboratory of Regional Sustainable Development Modeling CASBeijing 100101China College of Resource and Environment University of Chinese Academy of SciencesBeijing 100049China

The railway is an indispensable feature of a nation’s infrastructure,and the gauge isan internal and objective technical regulation of the *** the large-scale regional space,the track gauges reflect the development differences,historical relations and mutual influencesbetween countries and *** makes the railway,originally as a regional connection,have special social,political,military and other multiple *** on this,thepaper,from the perspective of railway gauge,takes the Eurasian continent as the case regionto explore the spatial pattern,formation mechanism and organizational mode of communicationof the Eurasian continental railway *** results show that 11 kinds of railwaygauge structures exist in Eurasia,which respectively belong to three types of wide-gauge,standard-gauge,and narrow-gauge,but the mainstream gauge only includes 1520 mm,1435mm and 1067 *** variation in the coverage length and space range of differentgauges is apparent,which provides a physical and technological basis for railway systemdifferentiation and network fragmentation,which leads to the formation of eight *** to different modes for railway transport management in different geographicallocations,the geographical pattern and geographical relationship of four transportorganizations are *** especially important is the emergence of“1435 gauge space”and“1520 gauge space”,as well as the railway geo-space confrontation between them,onthe Eurasian ***,we also find that the railway geo-system of Eurasia is mainlyaffected by the technology dissemination,path dependence,geopolitics,national defenseand the colonial expansion of military latitude,and on this basis,five geo-modes of railwaygauge propagation are formed.

关键词： railway railway geosystem development mechanism expansion mode

Disparities of Heatwave-Related Preterm Birth in Climate Types—China,2012-2019

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China CDC weekly 2023年第49期5卷 1093-1099,I0001,I0002页

作者： Yafei Guo Yanxia Xie Xiaohui Wei chenran Guo peiran chen Yanping Wang Yi Mu Xiaoming Shi Jun Zhu Juan Liang Qiyong Liu National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases National Institute for Communicable Disease Control and PreventionChinese Center for Disease Control and PreventionBeijingChina Chinese Center for Disease Control and Prevention Key Laboratory of Environment and Population Health National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijingChina National Office for Maternal and Child Health Surveillance of China West China Second University HospitalSichuan UniversityChengdu CitySichuan ProvinceChina Key Laboratory of Birth Defects and Related Diseases of Women and Children(Sichuan University) Ministry of EducationChengdu CitySichuan ProvinceChina School of Public Health Nanjing Medical UniversityNanjing CityJiangsu ProvinceChina Chinese Center for Disease Control and Prevention BeijingChina.

What is already known about this topic?An association between prenatal heatwave exposure and the risk of preterm birth was ***,the disparities in heatwave-related preterm birth across different climate types have not been *** is added by this report?This nationwide case-crossover study investigated the association between heatwave exposure and preterm birth across different Köppen-Geiger climate *** pregnant women residing in the arid-desertcold climate type,exposure to compound heatwaves was found to be associated with a significantly higher risk of preterm birth{adjusted odds ratios(AORs)ranged from 1.55[95%confidence interval(CI):1.21-1.97]to 2.11(95%CI:1.35-3.31)}.In contrast,among pregnant women residing in the tropical monsoonal climate type,exposure to daytime-only heatwaves was associated with an increased risk of preterm birth[AORs ranged from 1.25(95%CI:1.03-1.51)to 1.37(95%CI:1.05-1.77)].

关键词： climate monsoon tropical

费里尔型重排反应及其在活性分子合成应用中的最新进展

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有机化学 2011年第8期31卷 1195-1201页

作者：陈沛然向鹏东华大学化学化工与生物工程学院上海201620 中国科学院上海有机化学研究所生命有机化学国家重点实验室上海200032

对近10年来费里尔型重排反应(包括Ⅰ型费里尔重排、Ⅱ型费里尔重排和费里尔-皮塔西斯重排反应)的研究进展作了简要综述,并介绍了近来费里尔型重排反应应用于复杂的活性分子合成中的研究所取得的进展.

关键词：费里尔型重排反应 Ⅰ型费里尔重排 Ⅱ型费里尔重排费里尔-皮塔西斯重排反应复杂活性分子合成

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儿童审美想象的生成及其培育

当代教育科学 2024年第7期 37-44页

作者：陈沛然荆楚理工学院师范学院湖北荆门448000

审美想象是儿童重要的认知工具,是儿童对美的感受和体验,也是儿童通过记忆力中的审美表象产生出创造美和表达美的过程及其能力。培养与提升儿童审美想象对其审美感知力、情感发展、创造力、语言表达能力具有重要意义。儿童审美想象可分... 详细信息

审美想象是儿童重要的认知工具,是儿童对美的感受和体验,也是儿童通过记忆力中的审美表象产生出创造美和表达美的过程及其能力。培养与提升儿童审美想象对其审美感知力、情感发展、创造力、语言表达能力具有重要意义。儿童审美想象可分为先天性的审美想象、经验性的审美想象以及创造性的审美想象。儿童审美想象的生成过程是以感知觉为基础,经过审美表象的积累,最后形成创造性审美想象。课程活动培养儿童的审美想象,应确立以儿童为中心的审美想象价值取向,增强儿童的审美感受性体验,构建儿童审美化的完整经验世界,在实践活动中释放儿童的审美想象,以促进儿童的全面发展。

关键词：想象力审美想象美育审美教学

Association of interpregnancy interval and risk of adverse pregnancy outcomes in woman by different previous gestational ages

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Chinese Medical Journal 2024年第1期137卷 87-96页

作者： peiran chen Yi Mu Zheng Liu Yanping Wang Xiaohong Li Li Dai Qi Li Mingrong Li Yanxia Xie Juan Liang Jun Zhu National Office for Maternal and Child Health Surveillance of China West China Second University HospitalSichuan UniversityChengduSichuan 610066China Department of Obstetrics West China Second University HospitalSichuan UniversityChengduSichuan 610066China Key Laboratory of Birth Defects and Related Diseases of Women and Children Ministry of EducationSichuan UniversityChengduSichuan 610066China

Background:With an increasing proportion of multiparas,proper interpregnancy intervals(IPIs)are urgently ***,the association between IPIs and adverse perinatal outcomes has always been *** study aimed to explore the association between IPIs and adverse outcomes in different fertility policy periods and for different previous gestational ***:We used individual data from China’s National Maternal Near Miss Surveillance System between 2014 and *** Poisson models with restricted cubic splines were *** adverse outcome was analyzed separately in the overall model and stratified *** stratified models included different categories of fertility policy periods(2014-2015,2016-2017,and 2018-2019)and infant gestational age in previous pregnancy(<28 weeks,28-36 weeks,and≥37 weeks).Results:There were 781,731 pregnancies enrolled in this study.A short IPI(≤6 months)was associated with an increased risk of preterm birth(OR[95%CI]:1.63[1.55,1.71]for vaginal delivery[VD]and 1.10[1.03,1.19]for cesarean section[CS]),low Apgar scores and small for gestational age(SGA),and a decreased risk of diabetes mellitus in pregnancy,preeclampsia or eclampsia,and gestational hypertension.A long IPI(≥60 months)was associated with an increased risk of preterm birth(OR[95%CI]:1.18[1.11,1.26]for VD and 1.39[1.32,1.47]for CS),placenta previa,postpartum hemorrhage,diabetes mellitus in pregnancy,preeclampsia or eclampsia,and gestational *** policy changes had little effect on the association of IPIs and adverse maternal and neonatal *** estimated risk of preterm birth,low Apgar scores,SGA,diabetes mellitus in pregnancy,and gestational hypertension was more profound among women with previous term births than among those with preterm births or pregnancy ***:For pregnant women with shorter or longer IPIs,more targeted health care measures during pregnancy should be formulated according to infant gestational age in

关键词： Interpregnancy interval Fertility policy Gestational age Preterm birth Gestational hypertension Diabetes mellitus in pregnancy

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中小学生的审美识别能力及其培养

教育研究与实验 2022年第5期 87-92页

作者：陈沛然但武刚华中师范大学教育学院 430079 荆楚理工学院 448000

审美识别是审美能力的重要组成部分,是审美素养的基本要素。培养学生的审美识别能力是中小学校美育的基本内容。审美识别能力作为美育的起点,丰富学生的情感体验,影响学生鉴赏美、创造美等活动的顺利开展。审美识别的主要方式为:审美认... 详细信息

审美识别是审美能力的重要组成部分,是审美素养的基本要素。培养学生的审美识别能力是中小学校美育的基本内容。审美识别能力作为美育的起点,丰富学生的情感体验,影响学生鉴赏美、创造美等活动的顺利开展。审美识别的主要方式为:审美认知、审美辨别、审美分析。审美识别活动包括审美直觉的初步体验,通过审美认知来理解美的对象,重建知性思维来深入识别美的对象三个阶段。培养中小学生审美识别能力,应遵循由浅入深、循序渐进的原则,构建五育融合发展理念,积极引导学生进行深入审美探究学习,合理开发利用美育课程资源。

关键词：中小学生审美识别能力审美直觉审美认知知性思维

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汽车ABS控制系统建模方法的研究与实现

微计算机信息 2007年第35期23卷 254-255,304页

作者：陈培然王平重庆邮电大学计算机学院重庆400065

介绍ABS防抱死控制系统原理,阐述其发展历史、研究现状;然后通过分析ABS工作原理和控制方法,构建ABS专用模型库;运用VC实现模块的相关功能,对ABS控制系统进行建模;实现对控制器模块、电磁阀及制动系统模块、车辆运动仿真模块等部分的抽... 详细信息

介绍ABS防抱死控制系统原理,阐述其发展历史、研究现状;然后通过分析ABS工作原理和控制方法,构建ABS专用模型库;运用VC实现模块的相关功能,对ABS控制系统进行建模;实现对控制器模块、电磁阀及制动系统模块、车辆运动仿真模块等部分的抽象,使仿真的具体对象可替换,在ABS控制原理的基础上不同模块间可任意组合。

关键词： ABS 模型库建模

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广东省城市旅游竞争力评价与发展对策

中国科学院大学学报（中英文） 2017年第6期34卷 701-711页

作者：陈沛然张落成中国科学院南京地理与湖泊研究所南京210008 中国科学院大学北京100049

选取经济竞争优势、竞争潜力、基础支撑3个方面19个指标,采用基于熵权的灰色关联分析方法评价广东省各城市的旅游竞争力。结果表明广州和深圳旅游竞争力的综合评价系数远远高于其他城市;东莞、佛山、珠海、惠州等综合排序都处于前列,排... 详细信息

选取经济竞争优势、竞争潜力、基础支撑3个方面19个指标,采用基于熵权的灰色关联分析方法评价广东省各城市的旅游竞争力。结果表明广州和深圳旅游竞争力的综合评价系数远远高于其他城市;东莞、佛山、珠海、惠州等综合排序都处于前列,排序靠后的城市主要是位置较为偏远的揭阳、潮州、汕尾、阳江等。对城市规模与城市竞争力排序的关系进行研究。归纳广东省旅游竞争力的区域格局,即广东省的旅游业呈现出中心突出、四周下陷、环绕珠三角展开的核心-边缘结构。利用同样基于熵权的TOPSIS方法与原分析结果进行对比,确定分辨系数的可靠性和数据不稳定性的来源。最后从城市和区域2个尺度给出广东省提升旅游竞争力、发展区域旅游的建议和对策。

关键词：旅游竞争力熵权关联系数区域旅游广东省