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Spiro-fused bicyclo[3,2,2]octatriene-cored triptycene:synthesis,molecular packing,and functional aggregates

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Science China Chemistry 2021年第11期64卷 1976-1984页

作者： Qing Liu Xian Chen Zhibiao Zhou Tingting Huang yanpei wang Sheng Xie Zebing Zeng Ben Zhong Tang State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha410082China Aggregation-Induced Emission(AIE)Institute Guangzhou Development DistrictHuangpuGuangzhou510530China Shenzhen Institute of Aggregate Science and Technology School of Science and EngineeringThe Chinese University of Hong KongShenzhen518172China

Aggregate science has led to the existence of functional properties at the aggregate level that significantly differs from those of corresponding single-molecule species,leading to a number of novel conceptual materials with state-dependent *** developing such materials,new molecular scaffolds that allow modulating the structural and functional properties of aggregates in a controlled manner could be extremely *** this study,we report a class of spiro-fused bicyclo[3,2,2]octatriene triptycene derivatives with a unique 3 D molecular scaffolding structure that displays aggregation-induced emission(AIE)activity with bright solid-state blue *** core scaffold features a Y-shaped bicyclo[3,2,2]octatriene backbone and a vertical crossover arrangement of adjacent spiro-conjugated *** classic bicyclo[2,2,2]octatrienes with high rigidity,this stereoscopic bicyclo[3,2,2]octatriene containing a seven-membered ring allows retaining certain flexibility in the molecular scaffold,which results in a weak fluorescence in dilute solutions(Φ_(F)<10%).However,the corresponding molecular aggregates emit intense fluorescence(Φ_(F)=50%-75%)and show prominent AIE activity because of the restriction of intramolecular scaffold ***,in principle,these stereoscopic scaffold constructions with partially restricted flexibility facilitate the assembly of multiple different crystalline packing structures in both porous and nonporous forms depending on the growth conditions of crystalline *** obtained crystals with regular voids(12.85×6.89Aeach)show reversible luminescence in response to the adsorption/desorption of iodine *** materials based on an unusual 3 D scaffold exhibit a high degree of structural modulation at the aggregate level and demonstrate potential applications in chemical sensing and flexible optoelectronics,which may open up the exploration of highly stereoscopic molecular building blocks for developing functi

关键词： aggregate science triptycene aggregation-induced emission organic porous material

Spiro-conjugated indenodiarylethenes: enabling steric-induced electronic tuning of photochromic and photoluminescent properties by spiro-conjugation

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Science China Chemistry 2020年第11期63卷 1659-1665页

作者： Tingting Huang Hongyu Liu Yawen Bang yanpei wang Yuan Liang Xinhao wang Yang Zhang Sheng Xie Zebing Zeng Ben Zhong Tang State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China Jiurui Biotechnology Co. LtdZhangjiajie 427000China Department of Chemistry Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and ReconstructionThe Hong Kong University of Science&TechnologyHong KongChina Center for Aggregation-Induced Emission SCUT-HKUST Joint Research InstituteState Key Laboratory of Luminescent Materials and DevicesSouth China University of TechnologyGuangzhou 510640China

Light-operated excited-state photochemical reactions and the resulting photochromic materials have gained significant attention for their promising technological applications in molecular electronic and photonic *** obtain photochromic materials(e.g.,diarylethenes)with desired properties,the way to tune energy processes of the excited state is essentially important,from both fundamental and practical *** modified diarylethenes mostly focused on structural improvements to achieve efficient *** report here two new spiro-conjugated indenodiarylethenes(named,SFI-Th and SFI-Sul)with an orthogonally arranged spiroπ-*** spiro fluorene sterically constrains the free volume of photoactive side aromatic rings,while the spiro-conjugation points toward modulation of the decaying channels of excited-state energy,thus allowing for tuning photochromic *** spirodiarylethenes SFI-Th and SFI-Sul are readily accessible with low cost and show distinct photochromic and photoluminescent *** one hand,the SFI-Th bearing bisthienyl side rings,is an excellent photochromic switch showing high thermal stability and high fatigue resistance in both solution and amorphous state,likely benefited from steric-induced excited-state energy transfer into reversible photochemical reactions,owing to higherπ-orbital spiro-conjugation between the two molecular *** the other hand,the SFI-Sul with bissulfonyl side rings,most notably,displays quantitative photocyclization to yield SFI-Sulc upon ***,the ring-closed SFI-Sulc has an extremely slow photocycloreversion,and meanwhile immediately switches on emissive state with a strong fluorescence(Φf=0.57 in amorphous powder state).We study the modulated roles of spiroπ-scaffold in both cases computationally and experimentally,and attribute the facilitated photochemical reaction to the positively electronic effects of spiro-conjugation,and the photo-responsive radiative transitio

关键词： diarylethene photochromic reaction spiro-conjugation steric-induced electronic effect excited-state energy

Mapping Domain- and Age-Specific Functional Brain Activity for Children’s Cognitive and Affective Development

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Neuroscience Bulletin 2021年第6期37卷 763-776页

作者： Lei Hao Lei Li Menglu Chen Jiahua Xu Min Jiang yanpei wang Linhua Jiang Xu Chen Jiang Qiu Shuping Tan Jia-Hong Gao Yong He Sha Tao Qi Dong Shaozheng Qin State Key Laboratory of Cognitive Neuroscience and Learning&IDG/McGovern Institute for Brain Research Beijing Normal UniversityBeijing 100875China College of Teacher Education Southwest UniversityChongqing 400715China Key Laboratory of Beijing Key Laboratory of Brain Imaging and Connectomics Beijing Normal UniversityBeijing 100875China School of Information Engineering Huzhou UniversityHuzhou 313000China Key Laboratory of Cognition and Personality(SWU) Ministry of EducationChongqing 400715China Faculty of Psychology Southwest UniversityChongqing 400715China Beijing HuiLongGuan Hospital Peking UniversityBeijing 100096China Center for MRI Research Academy for Advanced Interdisciplinary StudiesPeking UniversityBeijing 100871China

The human brain undergoes rapid development during childhood,with significant improvement in a wide spectrum of cognitive and affective *** domain-and age-specific brain activity patterns has important implications for characterizing the development of children’s cognitive and affective *** current mainstay of brain templates is primarily derived from structural magnetic resonance imaging(MRI),and thus is not ideal for mapping children’s cognitive and affective brain *** integrating task-dependent functional MRI data from a large sample of 250 children(aged 7 to 12)across multiple domains and the latest easy-to-use and transparent preprocessing workflow,we here created a set of age-specific brain functional activity maps across four domains:attention,executive function,emotion,and risky ***,we developed a toolbox named Developmental Brain Functional Activity maps across multiple domains that enables researchers to visualize and download domain-and age-specific brain activity maps for various *** toolbox and maps have been released on the Neuroimaging Informatics Tools and Resources Clearinghouse website(http://***/projects/dbfa).Our study provides domain-and age-specific brain activity maps for future developmental neuroimaging studies in both healthy and clinical populations.

关键词： Brain activity maps FMRI Cognition Emotion Reward Development

The SACT Template:A Human Brain Diffusion Tensor Template for School-age Children

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Neuroscience Bulletin 2022年第6期38卷 607-621页

作者： Congying Chu Haoran Guan Sangma Xie yanpei wang Jie Luo Gai Zhao Zhiying Pan Mingming Hu Weiwei Men Shuping Tan Jia-Hong Gao Shaozheng Qin Yong He Lingzhong Fan Qi Dong Sha Tao National Key Laboratory of Cognitive Neuroscience and Learning&IDG/McGovern Institute for Brain Research Beijing Normal UniversityBeijing 100875China Bejing Key Laboratory of Brain Imaging and Connectomics Beijing Normal UniversityBejing 100875China Center for MRI Research Academy for Advanced Interdisciplinary StudiesPeking UniversityBeijing 100871China Beijing City Key Laboratory for Medical Physics and Engineering Institute of Heavy lon PhysicsSchool of PhysicsPeking UniversityBeijing 100871China MeGovern Institute for Brain Research Peking UniversityBeijing 100871China Psychiatry Research Center Bejing HuiLongGuan HospitalPeking UniversityBejing 100096China Division of Molecular Neuroimaging Institute of Neuroscience and Medicine-2Research Center Julich52425 JilichGermany Institute of Biomedical Engineering and Instrumentation School of AutomationHangzhou Dianzi UniversityHangzhou 310018China Brainnetome Center and National Laboratory of Pattern Recognition Institute of AutomationChinese Academy of SciencesBeijing 100190China

School-age children are in a specific development stage corresponding to juvenility,when the white matter of the brain experiences ongoing ***-weighted magnetic resonance imaging(DWI),especially diffusion tensor imaging(DTI),is extensively used to characterize the maturation by assessing white matter properties in *** the analysis of DWI data,spatial normalization is crucial for conducting inter-subject analyses or linking the individual space with the reference *** tensor-based registration with an appropriate diffusion tensor template presents high accuracy regarding spatial ***,there is a lack of a standardized diffusion tensor template dedicated to school-age children with ongoing brain ***,we established the school-age children diffusion tensor(SACT)template by optimizing tensor reorientation on high-quality DTI data from a large sample of cognitively normal participants aged 6-12 *** an age-balanced design,the SACT template represented the entire age range well by showing high similarity to the age-specific *** with the tensor template of adults,the SACT template revealed significantly higher spatial normalization accuracy and inter-subject coherence upon evaluation of subjects in two different datasets of schoolage children.A practical application regarding the age associations with the normalized DTI-derived data was conducted to further compare the SACT template and the adult *** similar spatial patterns were found,the SACT template showed significant effects on the distributions of the statistical results,which may be related to the performance of spatial *** forward,the SACT template could contribute to future studies of white matter development in both healthy and clinical *** SACT template is publicly available now(tp://igshare com/aricles/dataseu'SACT_.template/14071283).

关键词： School-age children Diffusion-weighted MRI Diffusion tensor template Spatial normalization

Stable Quadruple Helical Tetraradicaloid with Thermally Induced Intramolecular Magnetic Switching

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CCS Chemistry 2022年第1期4卷 95-103页

作者： Jing Guo Zhiyu Li Jun Zhang Bo Li Yuan Liang yanpei wang Sheng Xie Hoa Phan Tun Seng Herng Jun Ding Jishan Wu Ben Zhong Tang Zebing Zeng State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering/Shenzhen Research InstituteHunan UniversityChangsha 410082 School of Materials and Chemical Engineering Anhui Jianzhu UniversityHefei 230039 Jiurui Biotechnology Co. Ltd.Zhangjiajie 427000 Department of Chemistry National University of SingaporeSingapore 117543 Department of Materials Science and Engineering National University of SingaporeSingapore 119260 Department of Chemistry Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and ReconstructionInstitute for Advanced Study and HKUST-Shenzhen Research InstituteSCUT-HKUST Joint Research InstituteHong Kong University of Science and TechnologyHong Kong 999077

We report an air-stable tetraradicaloid based on a rarely explored perylenequinonoid(PQ)core,namely,tetrabenzo-annulated tetracyclopenta[b,e,k,n]perylene(TBCP),which has a quadruple helical *** validated by X-ray crystallographic analysis and theoretical calculations,the nonplanar TBCP possesses unique hybrid resonance structures of two open-shell singlet ***,magnetic measurements reveal that TBCP in powder form shows unusual magnetic hysteresis upon heating followed by cooling,corresponding to interconversion of structure isomers with different magnetic *** electronic properties can be rationalized as the response of structural changes to external thermal stimuli,accompanied by a subtle balance of two types of intramolecular magnetic interactions between four-site spin *** results provide a novel organic polyradicaloid as an unprecedented example of a functional material with the potential for intramolecular magnetic switching.

关键词： polycyclic hydrocarbons polyradicaloid electronic structure singlet-to-triplet energy gap intramolecular magnetic interaction

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脑电测量在儿童发展性障碍诊断中的应用

心理科学进展 2017年第12期25卷 2136-2144页

作者：徐琴芳王延培北京师范大学认知神经科学与学习国家重点实验室北京100875 南京特殊教育师范学院南京210038

脑电以及相关的测量方法在儿童脑发育与学习研究中拥有漫长的历史,脑电测量在临床上可以作为儿童脑发育及发展性障碍预测、诊断及干预效果的生物学指标。针对30年脑电研究的文献分析,对比了脑电的4种主要测量方法:事件相关电位ERP、EEG... 详细信息

脑电以及相关的测量方法在儿童脑发育与学习研究中拥有漫长的历史,脑电测量在临床上可以作为儿童脑发育及发展性障碍预测、诊断及干预效果的生物学指标。针对30年脑电研究的文献分析,对比了脑电的4种主要测量方法:事件相关电位ERP、EEG频谱分析、EEG时频分析和静息态EEG脑网络连接在儿童发展性障碍中的应用,分析了任务态和静息态下不同的测量方法及其特点,同时针对儿童发展性障碍的共性特征、特异性指标以及脑结构和功能异常等核心问题,提出未来研究要加强时域、频域、时频领域在方法学上的融合与互补,发挥脑电测量对发展性障碍早期筛选和诊断的作用。

关键词：发展性障碍 ERPs 频谱分析时频分析脑网络

含分布时滞的时滞微分系统多步龙格-库塔方法的时滞相关稳定性

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计算数学 2019年第1期41卷 104-112页

作者：丛玉豪胡洋王艳沛上海大学理学院数学系上海200444 上海海关学院上海201204

本文研究了一类含分布时滞的时滞微分系统的多步龙格-库塔方法的稳定性.基于辐角原理,本文给出了多步龙格-库塔方法弱时滞相关稳定性的充分条件,并通过数值算例验证了理论结果的有效性.

关键词：含分布时滞的时滞微分系统多步龙格-库塔方法弱时滞相关稳定性

U-10Mo/Zr单片式燃料元件堆内稳态热-力学性能研究

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核动力工程 2021年第6期42卷 254-260页

作者：郭子萱简晓彬李文杰张坤王鹏王严培中国核动力研究设计院核反应堆系统设计技术重点实验室成都610213 复旦大学航空航天系力学与工程仿真研究所上海200433

本文建立了U-10Mo/Zr单片式燃料元件的辐照性能模型以及热-力学本构关系,采用有限元方法进行非均匀辐照场中燃料元件稳态热-力学性能的数值模拟,获得并分析了U-10Mo/Zr单片式燃料元件温度、形变和应力的分布特点及变化规律。研究结果表... 详细信息

本文建立了U-10Mo/Zr单片式燃料元件的辐照性能模型以及热-力学本构关系,采用有限元方法进行非均匀辐照场中燃料元件稳态热-力学性能的数值模拟,获得并分析了U-10Mo/Zr单片式燃料元件温度、形变和应力的分布特点及变化规律。研究结果表明,燃料芯体厚度增量在芯体和包壳结合面附近达到最大,主要受到燃料辐照蠕变的影响;在较低燃耗条件下,燃料芯体高温辐照肿胀模拟结果与低温辐照肿胀试验结果相当;燃料芯体边角区域和包壳端面外侧区域存在应力集中。

关键词： U-Mo燃料单片式燃料元件热-力学性能研究试验堆有限元方法

高等教育与收入差距:基于非结构化模型的分析

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教育学术月刊 2015年第2期 3-10页

作者：卜振兴王延培陈欣南开大学经济学院国际经济研究所/国家经济战略研究院国家发改委价格监测中心南开大学高等教育研究所

近年来,我国收入不平等的状况十分突出,已经引起政府、学者以及社会各界的广泛关注。文章利用向量自回归模型、协整关系检验和误差修正模型等非结构化分析方法,实证检验了高等教育发展对收入不平等的影响。在重点考察高等教育对收入不... 详细信息

近年来,我国收入不平等的状况十分突出,已经引起政府、学者以及社会各界的广泛关注。文章利用向量自回归模型、协整关系检验和误差修正模型等非结构化分析方法,实证检验了高等教育发展对收入不平等的影响。在重点考察高等教育对收入不平等影响的同时,引入了经济增长和失业率等参考变量。经过检验发现:高等教育发展可以减少收入不平等,但是这种抑制作用较小,而经济增长和失业率的增加会加剧收入不平等状况。

关键词：高等教育发展收入不平等非结构化模型向量自回归模型协整关系检验误差修正模型