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Journal of Materials Science & Technology 2020年第11期42卷 177-184页

作者： Zheng Liu Jieqiong Wang Changhong Zhan Jing Yu Yang Cao Jinchun Tu changsheng shi State Key Laboratory of Marine Resource Utilization in South China Sea School of Materials Science and EngineeringSchool of ScienceHainan UniversityHaikou 570228China Qiongtai Normal University Haikou 571127China

The design and construction of effective and stable hydrogen evolution reaction(HER)catalysts represent the key to obtaining hydrogen energy *** metal phosphides(TMPs)have attracted considerable attention due to their unique catalytic mechanism,which is similar to ***,single-phase TMPs remain limited by their low activity and weak stability in alkaline *** this work,CoP@CoMoO4 nanosheets with phosphide and oxide heterostructure were synthesized on carbon cloth(CC)through hydrothermal method and subsequently reacted with red phosphorus in a tube *** outstanding synergy between CoP and CoMoO4 enhanced the HER activity and stability in alkaline *** CoP@CoMoO4/CC heterostructure exhibited excellent HER activity with a low overpotential of 89 mV at 10 mA cm^-2 with Tafel slope of 69 mV dec^-1,and outstanding stability when compared with single-phase *** present research provides a new approach for the preparation of inexpensive,highly active,and highly durable phosphorus-based catalyst for HER.

关键词： Phosphorus-oxide Heterostructure Stability Hydrogen evolution reaction

Fine Tuning of Donor-Acceptor Structures in Fused-Carbazole Containing Thermally Activated Delayed Fluorescence Materials towards High-Efficiency OLEDs

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Chinese Journal of Chemistry 2023年第15期41卷 1829-1835页

作者： Wenbo Yuan Weiyang Hu Jian Wang Mengyuan Zhu changsheng shi Ning Sun Youtian Tao Key Lab for Flexible Electronics&Institute of Advanced Materials(IAM) Nanjing Tech University30 South Puzhu RoadNanjingJiangsu 211816China Department of Physics Center for Optoelectronics Engineering ResearchYunnan UniversityKunmingYunnan 65091China

Comprehensive Summary Conjugated fused-ring structures have attracted extensive attention due to their high molecular rigidity to restrain excited-state relaxation and non-radiative decay,and further to enhance the luminance efficiency for emissive ***,we develop a series of donor-acceptor type thermally activated delayed fluorescence(TADF)emitters by introducing fused-ring 5H-benzofuro[3,2-c]carbazole(32BFCz)as electron donating *** optimizing the numbers and structure of donor and acceptor moieties,three compounds named 32BFCzA,mCF3BFCzOXD and dCF3BFCzOXD are designed,which are composed by mono-32BFCz/trifluoromethylpicolinonitrile,penta-BFCz/3-(trifluoromethyl)phenyl)-1,3,4-oxadiazol-2-yl)benzene and penta-32BFCz/3,5-bis(trifluoromethyl)phenyl)-1,3,4-oxadiazol-2-yl)benzene as donor/acceptor groups,respectively.

关键词： Donor-acceptor Dipole moment Thermally activated delayed fluorescence Organic light-emitting diodes External quantum efficiency

A High-quality Ultra-wideband Omni-direction Antenna

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A High-quality Ultra-wideband Omni-direction Antenna

Spatial-temporal Patterns of Urban Parks’Effects on the Sentiments and Their Associated Factors Based on Social Media Data——a Case Study in Beijing

1997 International Symposium on Electromagnetic Compatibility

作者： LU Mingyu shi changsheng Department of Electronic Engineering Tsinghua University

＜正＞A wideband omni-direction antenna is designed through using a new biconical model and the method of *** frequency band of ten octaves is realized,and the characteristic of radiation pattern at high frequencies i... 详细信息

ISBN: (纸本)0780336089

关键词： antenna radiation patterns high-quality ultra-wideband omni-direction antenna biconical model method of moments frequency band radiation pattern wire grid structure 500 MHz to 10 GHz

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Journal of Geodesy and Geoinformation Science 2024年第2期7卷 95-110页

作者： YUAN Yuting WANG Juan WEI Yali ZHU Yanrong shi changsheng MENG Bin College of Applied Arts and Science Beijing Union UniversityBeijing 100191China Laboratory of Urban Cultural Sensing&Computing Beijing Union UniversityBeijing 100191China Beijing Guohuan Environmental Technology Co. Ltd.Tangshan 063020China

As the pivotal green space,urban parks play an important role in urban residents’daily *** can not only bring people physical health,but also can be more likely to elicit positive sentiment to those who visit ***,social media big data has provided new data sources for sentiment ***,there was limited researches that explored the connection between urban parks and individual’s ***,this study firstly employed a pre-trained language model(BERT,Bidirectional Encoder Representations from Transformers)to calculate sentiment scores based on social media ***,this study analysed the relationship between urban parks and individual’s sentiment from both spatial and temporal ***,by utilizing structural equation model(SEM),we identified 13 factors and analyzed its degree of the *** research findings are listed as below:①It confirmed that individuals generally experienced positive sentiment with high sentiment scores in the majority of urban parks;②The urban park type showed an influence on sentiment *** this study,higher sentiment scores observed in Eco-parks,comprehensive parks,and historical parks;③The urban parks level showed low impact on sentiment *** distinctions observed mainly at level-3 and level-4;④Compared to internal factors in parks,the external infrastructure surround them exerted more significant impact on sentiment *** instance,number of bus and subway stations around urban parks led to higher sentiment scores,while scenic spots and restaurants had inverse *** study provided a novel method to quantify the services of various urban parks,which can be served as inspiration for similar studies in other cities and countries,enhancing their park planning and management strategies.

关键词： urban parks sentiment analysis social media data SEM Beijing

Molecular engineering on all ortho-linked carbazole/oxadiazole hybrids toward highly-efficient thermally activated delayed fluorescence materials in OLEDs

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Chinese Chemical Letters 2019年第11期30卷 1955-1958页

作者： Wenbo Yuan Hannan Yang Mucan Zhang Die Hu shigang Wan Zijing Li changsheng shi Ning Sun Youtian Tao Wei Huang Key Lab for Flexible Electronics&Institute of Advanced Materials(IAM) Nanjing Tech UniversityNanjing 211816China Department of Physics Center for Optoelectronics Engineering ResearchYunnan UniversityKunming 650091China Shaanxi Institute of Flexible Electronics(SIFE) North western Polytechnical University(NPU)Xi'an 710072China

The highest efficiency thermally activated delayed fluorescence(TADF)emitters in OLEDs are mostly based on twisted donor/acceptor(D/A)type organic ***,we report the rational molecular design on twisted all ortho-linked carbazole/oxadiazole(Cz/OXD)hybrids with tunable D-A interactions by adjusting the numbers of donor/acceptor units and electron-donating ***-triplet energy bandgaps(ΔEST)are facilely tuned from^0.4,0.15 to^0 eV in D-A,D-A-D to A-D-A type *** variation correlates well with triplet-excited-state frontier orbital spatial separation *** feature with solid state photoluminescence quantum yield(PLQY)<10%is observed in D-A type 2CzOXD and D-A-D type *** to the extremely lowΔEST for efficient reverse intersystem crossing,strong TADF with PLQY of 71%-92%is achieved in A-D-A type 4CzDOXD and *** external quantum efficiency from 19.4%to 22.6%is achieved in A-D-A typed 4CzDOXD and 4tCzDOXD.

关键词： Oxadiazole Carbazole Donor-acceptor Organic light-emitting diodes Thermally activated delayed fluorescence

The Radiation Emission Model of Twisted-Pairs

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The Radiation Emission Model of Twisted-Pairs

Predicting neutron star spins from twin kHz QPOs

1998 International Conference on Microwave and Millimeter Wave Technology

作者： Zhang You shi changsheng Electronic Department Tsinghua University

ISBN: (纸本)0780343085

＜正＞This paper establishes the emission model and formulas of the radiation field of twisted-pairs by applying the theory of helix *** considering the existence of the common mode current,we designed an experimental method of measuring the radiation field of the differential mode current on single-segment twisted-pairs terminated with open *** results match calculating results.

关键词： twisted pair cables antenna theory electromagnetic field theory radiation emission model twisted-pairs radiation field helix antenna theory common mode current differential mode current measurement open circuit termination single-segment type

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Science China(Physics,Mechanics & Astronomy) 2010年第S1期53卷 247-248页

作者： shi changsheng Department of Astronomy,Nanjing University,Nanjing 210093,China College of Material Science and Chemical Engineering,Hainan University,Hainan 570228,China 1. Department of Astronomy Nanjing University Nanjing 210093 China

We briefly review the proposed relations between the frequencies of twin kilohertz quasi-periodic oscillations(kHz QPOs) and the spin frequencies in neutron star low-mass X-ray binaries(NSLMXBs).To test the validity of the proposed models,we estimate the spin frequencies under these theoretical relations and compare them with the measured *** seems that magnetohydrodynamic(MHD) oscillations are more promising to account for the kHz QPOs.

关键词： win kHz QPOs spin neutron stars LMXBs

STUDY ON THE COMBINED DERIVATIVE SPECTROPHOTOMETRY

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湖南城市学院学报 1990年第5期14卷 1-8,19页

作者： Xi changsheng (Department of Chemistry)shi Huiming Li Jinghe(Department of Chemistry, Nakai University Tianjin,PRC) DepartmentofChemistry DepartmentofChemistry NakaiUniversityTianjin PRC

Summary-The combined derivative spectrophotometry developed bythis paper is a new method, which can be used for the simultaneous determination of mtulticomponent mixture and may be allowed to improve sensitivity and accuracy of the determination remarkably. Two practical tests were carried out to verify the correctness of the theory and the results were *** paper also made an approach to quantitative comparison of sensitivities of different methods, and the conception of the index of relative sensitivity has been proposed.

关键词： Combined derivative spectropotometry Derivative spectropotometry

冻结裂隙煤岩单轴压缩破坏机制及细观参数反演

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冰川冻土 2020年第4期42卷 1275-1284页

作者：史昌盛李双洋石梁宏王冲中国铁建股份有限公司北京100855 中国科学院西北生态环境资源研究院冻土工程国家重点实验室甘肃兰州730000 兰州大学土木工程与力学学院甘肃兰州730000

煤岩的变形破坏是一个复杂的渐进演化过程,为了研究冻结条件下裂隙煤岩的破坏机理,基于CT扫描图像,应用三维离散元模拟方法,建立了冻结裂隙煤岩的单轴压缩模型。对比分析数值试验与室内压缩试验得到的应力-应变曲线,发现二者吻合较好。... 详细信息

煤岩的变形破坏是一个复杂的渐进演化过程,为了研究冻结条件下裂隙煤岩的破坏机理,基于CT扫描图像,应用三维离散元模拟方法,建立了冻结裂隙煤岩的单轴压缩模型。对比分析数值试验与室内压缩试验得到的应力-应变曲线,发现二者吻合较好。通过对数值模拟结果的系统分析,得到了冻结裂隙煤岩的细观结构损伤过程和宏观变形破坏规律,也发现了煤岩的弹性模量和强度随温度变化的发展规律,同时给出了煤岩强度和弹性模量与温度的数学关系式。以上研究表明,离散元模拟方法能够为研究冻结裂隙煤岩的细观损伤演化和宏观破坏变形提供新思路,可为岩体工程的安全稳定分析提供理论依据和参数基础。

关键词：冻结裂隙煤岩应力-应变关系位移离散单元法

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数字地下空间与工程的空间分析与知识发现

铁道建筑技术 2010年第2期 29-34页

作者：史昌盛中铁第五勘察设计院集团有限公司北京102600

建立完善的空间数据分析理论和方法体系,集成先进的空间数据分析工具,增强数字地下空间与工程的空间分析能力,使数据型数字地下空间与工程上升为分析型信息系统,是数字地下空间与工程技术与应用的发展目标和趋势。首先论述数字地下空间... 详细信息

建立完善的空间数据分析理论和方法体系,集成先进的空间数据分析工具,增强数字地下空间与工程的空间分析能力,使数据型数字地下空间与工程上升为分析型信息系统,是数字地下空间与工程技术与应用的发展目标和趋势。首先论述数字地下空间与工程特有的空间分析功能,如三维图形剖切、实体切割、管线碰撞分析、三维最小距离、对象属性查询等;然后论述数据分析领域迅速发展的新技术——数据挖掘与知识发现。

关键词：地下空间空间分析数据挖掘