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Changes in Atmospheric Circulation during the Winter Regional Extreme Cold Events over China since 1960

Journal of Meteorological Research 2023年第5期37卷 589-603页

作者： dongxue FU Yihui ding School of Atmospheric Sciences Nanjing University of Information Science&TechnologyNanjing 210044 Chinese Academy of Meteorological Sciences China Meteorological AdministrationBeijing 100081 Jilin Climate Center Changchun 130062 National Climate Centre China Meteorological AdministrationBeijing 100081

The number of days with occurrence of winter regional extreme cold events(RECEs) in China was found more during 1960/1961–1985/1986(period 1), less during 1986/1987–2005/2006(period 2), but more again during2006/2007–2017/2018(period 3). So far, the differences in the atmospheric circulation favoring RECEs among these three periods are unclear. In this paper, changes in atmospheric circulation during the RECEs over China are examined by using composite analysis based on the station observed temperature data and NCEP–NCAR reanalysis data in winters of 1960/1961–2017/2018. The results show:(1) the stratospheric polar vortex was more active and tended to split before the outbreak of RECEs in period 3 than that in other two periods. The shift of the stratospheric polar vortex to Eurasia helped the upper Arctic cold air to affect the lower latitudes.(2) The troposphere was characterized by a typical or significant three-wave pattern before the outbreak of RECEs in period 2, in contrast to a weakened three-wave pattern in period 1. Compared to periods 1 and 2, the Okhotsk blocking high was stronger in period 3, contributing to the inverted omega-shaped circulation pattern in East Asia–North Pacific section and a shift of global pattern from three-wave to two-wave. The weakened three-wave or two-wave circulation pattern was manifested by the stronger Ural/Okhotsk blocking high, conducive to the strengthening of the meridional circulation and the occurrence of RECEs in East Asia.(3) The Siberian high was the strongest in period 3, followed by period 1, and it was the weakest in period 2. Before the outbreak of RECEs, the Siberian high in period 3 began to intensify one week earlier than that in periods 1 and 2. Thus, the accumulation time of cold air mass in period 3 was the longest. In summary, the synergism of atmospheric circulation at high and low levels in periods 1 and 3 was more conducive to more and strong RECEs than that in period 2. Moreover, the split of the stratospheric polar vortex may have played an import

关键词： regional extreme cold events interdecadal variation polar vortex blocking high East Asian trough

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Super rigid tris-spirobifluorenes:Syntheses and properties

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Chinese Chemical Letters 2021年第1期32卷 397-400页

作者： Luyao Zhao Chunbo Duan Dongxue Ding Shihui Liu Debin Xia Ying Guo Hui Xu Martin Baumgartend College of Chemical and Environmental Engineering.Horbin Universty of Science and Tetenologo Herbin 150040 China MIT Key Laboratory'of Crtcal Materials Technology for New Energy Conversion and Storge School of Chemisty and Chermical Engineering Harbin Instiute of Technology.Harbin 150001 China Key Laboratory of Functional lnorganic Material Chemistry Ministy of EducarionSchool of Chermistry and Materiol ScienceHeilongjiang UniversiyHarbin 150080China Max Planck Istitute for Pobymer Research Mainz 55128Cermpay

In this work,a blue emitter with a 3 D rigid structure composed of multiple spirobifluorene(3-Spiro) has been synthesized and characterized.Through a detailed study of the electrochemical and photophysical properties of 3-Spiro,we have evidenced that 3-Spiro can be applied as an active component of organic light-emitting diodes(OLEDs).The device with 5% doping rate of 4 CzPNPh exhibits high external quantum efficiency(EQE) of 11%,which proves the potential of 3 D rigid structure emitters for OLEDs.

关键词： OLEDs Spirobifluorene Blue emitter Rigid structure Three dimensional

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White Fluorescent Organic Light-Emitting Diodes with 100%Power Conversion

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Research 2023年第1期2022卷 535-544页

作者： Dongxue Ding Zicheng Wang Chunbo Duan Chunmiao Han Jing Zhang Shuo Chen Ying Wei Hui Xu Key Laboratory of Functional Inorganic Material Chemistry Ministry of EducationSchool of Chemistry and MaterialsHeilongjiang UniversityHarbinHeilongjiangChina

Energy-efficient lighting sources are desired to provide another solution of carbon emission reduction.White organic light-emitting diodes are promising,because of theoretical internal quantum efficiencies for 100%electric-to-light conversion.However,pure organic fluorescent materials still face a challenge in harvesting triplet excitons for radiation.Herein,we report a white fluorescent organic light-emitting diode having an external quantum efficiency of 30.7%and a power efficiency of 120.2 Im w^(-1).In the single emissive layers,we use blue thermally activated delayed fluorescent emitters to sensitize a yellow fluorescent emitter.Transient photoluminescence and electroluminescence analyses suggest that a blue thermally activated delayed fluorescent molecule with~100%reverse intersystem crossing efficiency and negligible triplet nonradiative rate constant completely converts triplet to singlet,suppressing triplet quenching by a yellow fluorescent emitter and ensuring 100%power conversion.

关键词： emitter quantum yellow

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Carbazole-endcapped Spiro[fluorene-9,9＇-xanthene] with Large Steric Hindrance as Hole-transporting Host for Heavily-doped and High Performance OLEDs

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Chinese Journal of Chemistry 2015年第8期33卷 955-960页

作者： Xianghua Zhao Yukun Wu Nannan Shi Xiaoyu Li Yi Zhao Mingli Sun Dongxue Ding Hui Xu Linghai Xie College of Chemistry and Chemical Engineering Xinyang Normal University Xinyang Henan 464000 China State Key Laboratory on Integrated Optoelectronics College of Electronics Science and Engineering Jilin University 2699 Qianjin Street Changchun Jilin 130012 China China Key Laboratory for Organic Electronics & Information Displays (KLOEID) Institute of Advanced Materials (IAM) Nanjing University of Posts & Telecommunications Nanjing Jiangsu 210046 China Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education Heilongjiang University Harbin Heilongjiang 150080 China

In this work, we designed and synthesized a novel spirocyclic compound functionalized spiro[fluorene-9,9＇- xanthene] with carbazole group （2-carbazolyl-spiro[fluorene-9,9＇-xanthene], SFX-Cz） via Friedel-Crafts and Ullmann reaction, which is expected to own high thermal and morphological stability, and good carrier injection/ transporting properties due to the excellent hole transporting characteristics of carbazole and cruciform structure of spiro[fluorene-9,9＇-xanthene]. The carbazole end-capped spiro[fluorene-9,9＇-xanthene] SFX-Cz based PhOLEDs with Flrpic as phosphor emitter have been researched by varying dopant concentration, which exhibit the maximum EQEs of 8.9%, 7.4%, 9.1%, and 4.7% with the doping increasing from 10% to 50%. The higher performance PhOLEDs are independent on concentration variation from 10% to 30%, which suggests the bulky steric hindrance of SFX-Cz might be a potential canditate for high performance and inexpensive device with simplified process.

关键词： steric hindrance spirocyclic compound heavily-doped PhOLEDs inexpensive device

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A Bulky Pyridinylfluorene/Triphenylamine Hybrid Used as Host Material for Heavily-Doped Blue Electrophosphorescent Devices

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Chinese Journal of Chemistry 2016年第4期34卷 397-402页

作者： Xianghua Zhao Yukun Wu Li Zhou Nana Wu Lin Tang Yi Zhao Xiaosheng Li Dongxue Ding Hui Xu College of Chemistry and Chemical Engineering Xinyang Normal University Xinyang 464000 Henan China State Key Laboratory on Integrated Optoelectronics College of Electronics Science and Engineering Jilin University Changchun Jilin 130012 China Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education Heilongjiang University Harbin Heilongfiang 150080 China

In this work, a novel molecule pyridinylfluorene/triphenylamine hybrid （TPyFTPA） with bulky steric hindrance effects has been synthesized successfully by substituting 9-（pyridine-2-yl）-fluoren-9-yl with triphenylamine （TPA） via Friedel-Crafts reaction, which possesses good thermal stability and triplet energy （ET） of 420 ℃ with 5% weight loss and 2.86 eV, respectively. Moreover, the bulky steric hindrance material shows high stable morphology by heating to 200 ℃ without finding melting phenomena and crystallization that is demonstrated by differential scanning calorimetry （DSC） curve. The bulky pyridinylfluorene end-capped TPA has been used as host material for blue phosphorescent organic light-emitting diodes （PhOLEDs） with maximum external quantum efficiencies （EQEs） of 2.7%, 3.7%, and 3.5%, at the doping ratios of 10%, 30%, and 40%, respectively. The performances of TPyFTPA-based blue PhOLEDs own wide concentration ranging from 10% to 40%, which indicates the bulky TPyFTPA might be a potential candidate for inexpensive products with simplifying process for the applications in full-color display and solid state lighting.

关键词： steric hindrance triphenylamine PhOLEDs high doping concentration

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齐泽克对马克思商品拜物教的拉康式解读

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科教文汇 2016年第2期 153-155页

作者：丁冬雪南京大学哲学系江苏南京220023

马克思的意识形态理论以资本主义社会的商品为落脚点,展开了对拜物教的批判。齐泽克创造性地将拉康的理论与马克思的商品拜物教思想巧妙结合,采取新颖的方法对其进行了深入的阐释,并用犬儒主义意识形态理论的新形式,为我们更好地探讨马... 详细信息

马克思的意识形态理论以资本主义社会的商品为落脚点,展开了对拜物教的批判。齐泽克创造性地将拉康的理论与马克思的商品拜物教思想巧妙结合,采取新颖的方法对其进行了深入的阐释,并用犬儒主义意识形态理论的新形式,为我们更好地探讨马克思的思想提供了一个有效的切入点。

关键词：齐泽克马克思商品拜物教意识形态

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生态产品价值实现与城乡融合发展——基于城乡融合发展试验区的实证研究

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统计研究 2024年第2期41卷 87-99页

作者：孙玉环张冬雪梁雨萩丁娇东北财经大学统计学院辽宁大学公共管理学院

生态产品价值实现对于巩固和拓展脱贫攻坚成果和实现乡村全面振兴,推动城乡融合发展具有重要意义。本文以2013—2020年城乡融合发展试验区77个区县为研究对象,构建评价体系并结合熵值法衡量城乡融合发展水平,明确生态产品价值实现流程,... 详细信息

生态产品价值实现对于巩固和拓展脱贫攻坚成果和实现乡村全面振兴,推动城乡融合发展具有重要意义。本文以2013—2020年城乡融合发展试验区77个区县为研究对象,构建评价体系并结合熵值法衡量城乡融合发展水平,明确生态产品价值实现流程,在此基础上,考察生态产品价值实现对城乡融合发展的影响效应及作用机制。研究发现,生态产品价值实现能显著促进城乡融合发展,在克服可能存在的内生性问题后,生态产品价值实现对城乡融合发展的影响效应仍然稳健;生态产品价值实现对城乡各系统层面融合也具有明显的促进作用;生态产品价值实现对城乡融合发展的影响主要基于环境效应和就业效应两个方面发挥作用;异质性分析发现,生态产品价值实现对东部和中部板块城乡融合发展均有正向促进作用,但是西部板块生态产品价值实现对城乡融合发展的促进作用并不显著。

关键词：生态产品价值实现城乡融合环境效应就业效应

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Geographical Distribution of Phacellaria Benth.(Santalaceae)and its Hosts

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Frontiers in Biology 2006年第1期1卷 5-8页

作者： Li dongxue ding Yulong College of Forest Resources and Environment Nanjing Forestry UniversityNanjing 210037China

Based on the geographical distribution of the species of Phacellaria and its host plants in the world,we speculated on the possible time,sites,and migration of the origin of Phacellaria.The host plants of Phacellaria mainly belong to Loranthaceae.Plants of Phacellaria and their hosts are mainly distributed in tropical and subtropical areas.The plants of Phacellaria might have originated from a tropical area in the south of China before the Tertiary.Their ancestors were parasitic on the ancestors of some plants of Loranthaceae by chance during the Tertiary.It possibly took them millions of years to form a sturdy relationship with their hosts.

关键词： Phacellaria geographical distribution host plant origin

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幽门螺杆菌感染致机体应激反应在胃黏膜疾病中的作用

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胃肠病学 2021年第8期26卷 503-506页

作者：张冬雪石岩岩丁士刚北京大学第三医院消化内科北京大学第三医院临床流行病学研究中心100183

幽门螺杆菌(Hp)是一种选择性定植于胃黏膜的革兰阴性杆菌,是诱导产生慢性胃炎乃至胃癌的主要因素之一。近年研究表明,Hp感染诱导机体产生各种应激反应,包括氧化应激、亚硝化应激和内质网应激。Hp能刺激中性粒细胞、巨噬细胞和胃上皮细... 详细信息

幽门螺杆菌(Hp)是一种选择性定植于胃黏膜的革兰阴性杆菌,是诱导产生慢性胃炎乃至胃癌的主要因素之一。近年研究表明,Hp感染诱导机体产生各种应激反应,包括氧化应激、亚硝化应激和内质网应激。Hp能刺激中性粒细胞、巨噬细胞和胃上皮细胞表达活性氧和活性氮,导致体内过度累积,加重炎症和胃黏膜损伤,这种长期的炎症和氧化应激状态可能增加癌变的风险。此外,Hp诱导的内质网应激在癌前病变形成的早期阶段发挥重要作用。本文就Hp感染所致的应激反应在胃黏膜疾病中的研究进展作一综述。

关键词：幽门螺杆菌氧化性应激亚硝化应激内质网应激胃黏膜疾病

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北京市海淀区大学生低碳理念下体育生活方式的现状研究

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当代体育科技 2020年第19期10卷 115-117页

作者：丁冬雪王耀东中国矿业大学(北京)体育教研部北京100083

随机抽取北京市海淀区5所院校500名在校大学生,本文以大学生低碳理念下体育生活方式的现状为研究对象,采用问卷调查法、文献资料法和逻辑分析法,对现状进行研究和分析,通过了解当代大学生的"低碳理念",结合体育生活方式,更深层次地了解... 详细信息

随机抽取北京市海淀区5所院校500名在校大学生,本文以大学生低碳理念下体育生活方式的现状为研究对象,采用问卷调查法、文献资料法和逻辑分析法,对现状进行研究和分析,通过了解当代大学生的"低碳理念",结合体育生活方式,更深层次地了解当代大学生的体育生活方式的现状,旨在提高当代大学生的低碳意识,提倡低碳理念的体育生活方式,提高大学生的低碳意识,增强大学生的身体素质。

关键词：低碳理念大学生体育生活方式低碳锻炼

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