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靛红双氮二苯腙分子开关的光致异构化机理

物理学报 2024年第17期73卷 151-160页

作者：庞晓娟赵凯玥何航宇张宁波蒋臣威中国矿业大学材料与物理学院徐州221116 中国矿业大学矿业工程学院徐州221116 西安交通大学物理学院凝聚态物质非平衡合成与调制教育部重点实验室量子信息与量子光电器件陕西省重点实验室西安710049

腙类分子开关在超分子化学领域有非常重要的应用价值,基于靛红发色团发展出的新型腙类分子开关已被合成.因其具有可见光激发下的顺反异构化特征、衍生物的易合成性及对外界刺激的敏感性,其在生物化学领域具有重要的应用价值.然而,该新... 详细信息

腙类分子开关在超分子化学领域有非常重要的应用价值,基于靛红发色团发展出的新型腙类分子开关已被合成.因其具有可见光激发下的顺反异构化特征、衍生物的易合成性及对外界刺激的敏感性,其在生物化学领域具有重要的应用价值.然而,该新型分子开关的光致异构化机制尚不明确,异构过程是否存在新奇的现象也不得而知.本文采用基于半经验OM2/MRCI的轨迹面跳跃动力学方法,系统地研究了一种名为靛红双氮二苯腙分子开关E-Z异构化过程的光致异构化机理.研究发现该E构型分子开关的S_(1)激发态平均寿命约为107 fs,该分子开关的E-Z异构化量子产率为16.01%.通过对该分子开关光致异构化过程的计算,明确了两种不同分子开关异构化机制;除围绕C=N键旋转的传统分子开关异构机制之外,阐明了新的异构机制——分子开关转子部分面对面的扭转;通过时间分辨的荧光辐射谱的计算,预测了异构化过程中存在极快的荧光猝灭现象,并且伴随着荧光红移的发生;通过对计算得到的荧光光谱与激发态平均寿命的分析,提出了“暗态”的存在,并对“暗态”存在的原因给出了可能的解释.研究结果可为新型分子开关的设计及应用提供理论指导作用.

关键词：分子开关光致异构化激发态非绝热动力学

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InP中点缺陷迁移机制的第一性原理计算

物理学报 2024年第18期73卷 112-120页

作者：闫丽彬白雨蓉李培柳文波何欢贺朝会赵小红西安交通大学核科学与技术系西安710049 空军工程大学航空工程学院西安710038

磷化铟作为重要的第二代半导体材料,具有禁带宽度大、电子迁移率高、光电转换效率高、抗辐照性能强等优点,是制备航天器电子器件优良材料之一.但空间辐射粒子在磷化铟电子器件中会产生点缺陷,导致其电学性能发生严重下降.本文采用第一... 详细信息

磷化铟作为重要的第二代半导体材料,具有禁带宽度大、电子迁移率高、光电转换效率高、抗辐照性能强等优点,是制备航天器电子器件优良材料之一.但空间辐射粒子在磷化铟电子器件中会产生点缺陷,导致其电学性能发生严重下降.本文采用第一性原理方法对磷化铟中点缺陷的稳态结构进行研究,并计算了最近邻位点的缺陷迁移能.通过构建不同电荷态点缺陷的稳态结构,发现了4种稳态结构的铟间隙和3种稳态结构磷间隙.研究空位点缺陷的迁移过程,发现磷空位比铟空位迁移能高,同时带电空位点缺陷迁移能高于中性空位.对于间隙点缺陷迁移过程的研究发现,相较于空位点缺陷,间隙点缺陷迁移能更小.在不同电荷态的铟间隙迁移过程计算中,发现了两种不同的迁移过程.计算磷间隙的迁移过程,发现了特殊的中间态结构引起多路径迁移情况.研究结果有助于深入了解磷化铟材料中缺陷的形成机制和迁移行为,对于设计和制造空间环境中长期稳定运行的磷化铟器件有重要意义.

关键词：磷化铟第一性原理点缺陷迁移

A visual-textual fused approach to automated tagging of flood-related tweets during a flood event

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International Journal of Digital Earth 2019年第11期12卷 1248-1264页

作者： xiao huang Cuizhen Wang Zhenlong Li huan ning Department of Geography University of South CarolinaColumbiaSCUSA

In recent years,social media such as Twitter have received much attention as a new data source for rapid flood *** timely response and large coverage provided by citizen sensors significantly compensate the limitations of non-timely remote sensing data and spatially isolated river ***,automatic extraction of flood tweets from a massive tweets pool remains a *** the Houston Flood in 2017 as a study case,this paper presents an automated flood tweets extraction approach by mining both visual and textual information a tweet contains.A CNN architecture was designed to classify the visual content of flood pictures during the Houston Flood.A sensitivity test was then applied to extract flood-sensitive keywords that were further used to refine the CNN classified results.A duplication test was finally performed to trim the database by removing the duplicated pictures to create the flood tweets pool for the flood *** results indicated that coupling CNN classification results with flood-sensitive words in tweets allows a significant increase in precision while keeps the recall rate in a high *** elimination of tweets containing duplicated pictures greatly contributes to higher spatio-temporal relevance to the flood.

关键词： Data mining flood social media CNN tweets geotagging

高铁候车厅行李火灾燃烧蔓延特性全尺寸试验研究

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消防科学与技术 2024年第7期43卷 971-975页

作者：欧宸肖倪琪张宁赵家明中国建筑科学研究院有限公司建筑防火研究所北京100013 建研防火科技有限公司北京100013

为了给高铁候车厅火灾安全设计(考虑行李火灾)提供参考,在某候车厅局部区域采用5 MW量热仪开展全尺寸行李火灾燃烧试验。采用50 cm×34 cm×20 cm行李箱(承装外套、裤子、短袖、内裤、袜子)、编织袋(承装被子、枕头、被褥)、双肩包(承... 详细信息

为了给高铁候车厅火灾安全设计(考虑行李火灾)提供参考,在某候车厅局部区域采用5 MW量热仪开展全尺寸行李火灾燃烧试验。采用50 cm×34 cm×20 cm行李箱(承装外套、裤子、短袖、内裤、袜子)、编织袋(承装被子、枕头、被褥)、双肩包(承装书本、笔记本、笔盒、笔、充电宝)等典型可燃物组成行李堆,监测记录了热释放速率、温度、辐射热流等特征参数的变化规律。结果表明:全尺度行李火灾燃烧呈现出明显的阶段性特征,其中发展阶段的温升和热释放速率增长最快,且在行李火灾的增长阶段,热释放速率的变化与t2快速火(增长系数为0.0469)模型吻合较好。在当前场景中,行李箱、编织袋、双肩包等行李可燃物最大火灾热释放速率达到1004 kW,最高温度接近640℃。在当前全尺寸行李火灾中,距离燃烧行李堆1 m处的可燃物均未被引燃,但出现了软化、熔融现象。在一定程度上,1 m的间隔距离可有效避免行李明火的连续蔓延。设置9 m的隔离带可以有效起到防火隔热的作用,距离燃烧行李堆9 m位置的温升和辐射热流变化并不明显。

关键词：高铁站厅行李火灾燃烧特性火蔓延全尺寸试验

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废旧三元锂离子电池回收利用碳足迹

环境科学 2024年第6期45卷 3459-3467页

作者：宋晓聪杜帅谢明辉邓陈宁郭静沈鹏赵慈陈忱中国环境科学研究院环境基准与风险评估国家重点实验室北京100012 中国环境科学研究院环境技术工程有限公司北京100012

公路运输是我国交通运输领域主要温室气体排放源,新能源汽车行业作为实现交通运输领域“双碳”目标的重要抓手,未来面临大批动力电池报废情况,为量化评估废旧锂电池回收利用行业产生的碳减排效益,从生命周期角度构建废旧三元锂电池回收... 详细信息

公路运输是我国交通运输领域主要温室气体排放源,新能源汽车行业作为实现交通运输领域“双碳”目标的重要抓手,未来面临大批动力电池报废情况,为量化评估废旧锂电池回收利用行业产生的碳减排效益,从生命周期角度构建废旧三元锂电池回收利用碳足迹核算模型,通过优化电力结构和运输结构,对废旧锂电池回收利用的碳减排潜力作预测评估,此外,使用误差传播方程进行不确定性分析保证碳足迹结果的可靠有效.结果表明,当前中国企业使用湿法技术回收1 kg废旧三元锂电池的碳足迹为-2 760.90 g(定向循环工艺)和-3 752.78 g(循环再造工艺),碳足迹的不确定性分别为16%(定向循环工艺)和15%(循环再造工艺).从碳排放贡献率分析,再生产品阶段是废旧三元锂电池湿法回收利用减碳首要贡献来源,电池获取、拆解和末端处置阶段是增碳主要来源.相比于优化运输结构,通过优化电力结构,可有效实现更大的碳减排潜力,协同优化情景下,相比于优化前可实现14%~19%的碳减排,与原生产品相比定向循环工艺和循环再造工艺分别可实现9%和11%的减排潜力.

关键词：废旧锂电池湿法回收碳足迹减排潜力不确定性分析

Chinese Society of Cardiology guidelines on the diagnosis and treatment of adult fulminant myocarditis

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Science China(Life Sciences) 2024年第5期67卷 913-939页

作者： Chinese Society of Cardiology,Chinese Medical Association,Writing Group Jiangang Jiang Hongyang Shu Dao Wen Wang Rutai Hui Chenze Li xiao Ran Hong Wang Jing Zhang Shaoping Nie Guanglin Cui Dingcheng Xiang Qun Shao Shengyong Xu Discussion experts:ning Zhou Yuming Li Wei Gao Yuguo Chen Yuan Bian Guoping Wang Liming Xia Yan Wang Chunxia zhao Zhiren Zhang Yuhua zhao Jianan Wang Shaoliang Chen Hong Jiang Jing Chen Xianjin Du Mao Chen Yinxian Sun Sheng Li Hu Ding Xueping Ma Hesong Zeng Li Lin Shenghua Zhou Likun Ma Ling Tao Juan Chen Yiwu Zhou xiaomei Guo 不详 Tongji Hospital Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Fuwai Hospital National Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100037China Zhongnan Hospital of Wuhan University Wuhan 430062China Fuwai Huazhong Cardiovascular Hospital Zhengzhou 450003China Beijing Anzhen Hospital Capital Medical UniversityBeijing 100029China Guangzhou General Hospital of Guangzhou Military Command Guangzhou 510010China Harbin Medical University Cancer Hospital Harbin 150081China Union Hospital Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China Taida Hospital Tianjin 300457China Peking University Third Hospital Beijing 100191China Qilu Hospital of Shandong University Jinan 250012China Kanghua Hospital DongguanGuangzhou 523080China Second Affiliated Hospital Zhejiang University School of Medicine Hangzhou 310003China Nanjing First Hospital Nanjing Medical UniversityNanjing 210006China Renmin Hospital of Wuhan University Wuhan 430060Wuhan West China Hospital Sichuan UniversityChengdu 610044China First Hospital of China Medical University Shenyang 110002China General Hospital of ningxia Medical University Yinchuan 750003China The Second Xiangya Hospital Central South UniversityChangsha 410012China The First Affiliated Hospital of USTC University of Science and Technology of ChinaHefei 230002China The First Affiliated Hospital of Air Force Medical University Xi’an 710032China Central Hospital of Wuhan City Wuhan 430014China Tongji Medical College Huazhong University of Science and TechnologyWuhan 430030China

Fulminant myocarditis is an acute diffuse inflammatory disease of *** is characterized by acute onset,rapid progress and high risk of *** pathogenesis involves excessive immune activation of the innate immune system and formation of inflammatory *** to China’s practical experience,the adoption of the“life support-based comprehensive treatment regimen”(with mechanical circulation support and immunomodulation therapy as the core)can significantly improve the survival rate and long-term *** emphasis is placed on very early identification,very early diagnosis,very early prediction and very early treatment.

关键词： fulminant myocarditis guidelines life support-based comprehensive treatment regimen diagnosis treatment cytokine storm overactivation of immunity

Analysis and Simulations of Open-Source Intelligence Process System Dynamics from User’s Perspective

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Computer Modeling in Engineering & Sciences 2023年第1期134卷 541-558页

作者： huan Liu Zhenyu Tang ning zhao Wei Qian Northeast Agricultural University Harbin150030China Harbin Institute of Technology Library Harbin150001China

In today’s society with advanced Internet,the amount of information increases dramatically with each passing day,which leads to increasingly complex processes of open-source ***,it is more important to rationalize the operation mode and improve the operation efficiency of open-source intelligence under the premise of satisfying users’*** paper focuses on the simulation study of the process system of opensource intelligence from the user’s ***,the basic concept and development status of open-source intelligence are introduced in ***,six existing intelligence operation process models are summarized and their advantages and disadvantages are compared in *** on users’preference,the open-source intelligence system simulation theory model is constructed from four aspects:intelligence collection,intelligence processing,intelligence analysis,and intelligence ***,the dynamics model of the open-source intelligence process system is constructed based on the open-source intelligence system simulation theoretical model,which specifically includes five parts:determination of system boundary,construction of causal loop diagram,construction of stock flow diagram,writing ofmathematical equations,and system sensitivity ***,the system simulation results were *** was found that improving the system of intelligence agencies,opening up government affairs,improving the professional level of intelligence personnel,strengthening the communication and cooperation among personnel of various intelligence departments,and expressing intelligence products through diverse forms can effectively improve the operational efficiency of the open-source intelligence process system.

关键词： Open-source intelligence system dynamics feedback user demand deviation

Influence of Hot Press Forming Techniques on Properties of Vehicle High Strength Steels

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Journal of Iron and Steel Research International 2011年第5期18卷 59-63页

作者： CHANG Ying MENG zhao-huan YING Liang LI xiao-dong MA ning HU Ping School of Automotive Engineering State Key Laboratory of Structural Analysis for Industrial EquipmentDalian University of TechnologyDalian 116024LiaoningChina

Based on the combination of materials science and mechanical engineering,hot press forming process of the vehicle high strength steels was analyzed. The hot forming process included：heating alloys rapidly to austenite microstructures,stamping and cooling timely,maintaining pressure and quenching. The results showed that most of austenite microstructure was changed into uniform martensite by the hot press forming while the samples were heated at 900 ℃ and quenched. The optimal tensile strength and yield strength were up to 1530 MPa and 1000 MPa,respectively,and the shape deformation reached about 23%. And springback defect did not happen in the samples.

关键词： high strength steel lightweight hot forming martensite

Genome assembly of autotetraploid Actinidia arguta highlights adaptive evolution and enables dissection of important economic traits

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Plant Communications 2024年第6期5卷 173-192页

作者： Xue-Mei Lu xiao-Fen Yu Guo-Qiang Li Ming-Hao Qu huan Wang Chuang Liu Yu-Ping Man xiao-Han Jiang Mu-Zi Li Jian Wang Qi-Qi Chen Rui Lei Cheng-Cheng zhao Yun-Qiu Zhou Zheng-Wang Jiang Zuo-Zhou Li Shang Zheng Chang Dong Bai-Lin Wang Yan-Xiang Sun Hui-Qin Zhang Jie-Wei Li Quan-Hui Mo Ying Zhang Xin Lou Hai-Xu Peng Ya-Ting Yi He-Xin Wang Xiu-Jun Zhang Yi-Bo Wang Dan Wang Li Li Qiong Zhang Wen-Xia Wang Yongbo Liu Lei Gao Jin-Hu Wu Yan-Chang Wang CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture Wuhan Botanical GardenChinese Academy of SciencesWuhanHubeiChina Key Laboratory of Western China’s Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhouGansuChina College of Life Sciences University of Chinese Academy of SciencesBeijingChina Wuhan Frasergen Bioinformatics Co. LtdWuhanHubeiChina Institute of Soil and Fertilizer Anhui Academy of Agricultural SciencesHefeiChina College of Agricultural Sciences Xichang UniversityXichangSichuanChina Department of Horticulture Heilongjiang Academy of Agricultural SciencesHarbinHeilongjiangChina College of Life Sciences Langfang Normal UniversityLangfangHebeiChina Institute of Horticulture Zhejiang Academy of Agricultural SciencesHangzhouZhejiangChina Guangxi Institute of Botany Chinese Academy of SciencesGuilinGuangxiChina Xi’an Botanical Garden of Shaanxi Province Institute of Botany of Shaanxi ProvinceXi’anShaanxiChina Institute of Modern Agricultural Research Dalian UniversityDalianLiaoningChina Bioinformatics Center College of Plant Science and TechnologyBeijing University of AgricultureBeijingChina College of Agriculture Eastern Liaoning UniversityDandongLiaoningChina Dalian Institute of Chemical Physics Chinese Academy of SciencesDalianLiaoningChina State Environmental Protection Key Laboratory of Regional Eco-process and Function Assessment Chinese Research Academy of Environmental SciencesBeijingChina Hubei Hongshan Laboratory WuhanHubeiChina The New Zealand Institute for Plant and Food Research Limited AucklandNew Zealand

Actinidia arguta,the most widely distributed Actinidia species and the second cultivated species in the genus,can be distinguished from the currently cultivated Actinidia chinensis on the basis of its small and smooth fruit,rapid softening,and excellent cold *** evolution of tetraploid Actinidia species and the genetic basis of their important agronomic traits are still ***,we generated a chromosome-scale genome assembly of an autotetraploid male *** *** genome assembly was 2.77 Gb in length with a contig N50 of 9.97 Mb and was anchored onto 116 *** and clustering of 101 geographically representative accessions showed that they could be divided into two geographic groups,Southern and Northern,which first diverged 12.9 million years *** underwent two prominent expansions and one demographic bottleneck from the midPleistocene climate transition to the late *** genomics studies using paleoclimate data enabled us to discern the evolution of the species’adaptation to different historical *** genes(AaCEL1,AaPME1,and AaDOF1)related to flesh softening were identified by multi-omics analysis,and their ability to accelerate flesh softening was verified through transient expression assays.A set of genes that characteristically regulate sexual dimorphism located on the sex chromosome(Chr3)or autosomal chromosomes showed biased expression during stamen or carpel *** chromosome-level assembly of the autotetraploid *** genome and the genes related to important agronomic traits will facilitate future functional genomics research and improvement of ***.

关键词： kiwiberry dioecism adaptive evolution paleoclimate GEA rapid softening