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Double [5]carbohelicene: facile synthesis, chiroptical properties,isomerization study, and lasing application

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Science China Chemistry 2025年第1期68卷 233-240页

作者： Peipei Liu Yantong Li Meng-Xiang Wu Hao Kang Xiao-Li Zhao Lin Xu Linlin Liu Xiaodong Li Junfeng Fang Zhiwei Fang Ya Cheng Hai-Bo Yang Huakang Yu Xueliang Shi State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal University School of Physics and Optoelectronics South China University of Technology inst.tute of Polymer Optoelectronic Materials & Devices State Key Laboratory of Luminescent Materials & Devices South China University of Technology School of Physics and Electronic Science Engineering Research Center of Nanophotonics & Advanced Instrument Ministry of EducationEast China Normal University State Key Laboratory of Precision Spectroscopy School of Physics and Electronic Science East China Normal University

Double carbohelicenes have attracted considerable attention due to their aesthetic structures, distinct π-conjugation extension, inherent chirality, and intriguing optical and electronic properties. Herein, the concise de novo synthesis of a new double[5]carbohelicene 1 together with its chiroptical properties, isomerization process and lasing application is presented. 1 was synthesized by a simple protocol involving the formation of a 6,6′-bipentacene as the key intermediate. It is worth noting that1 existed as two diastereomers 1-PP/MM and 1-PM, which were successfully isolated and unambiguously confirmed by Xray crystallography. The optical resolution of the racemic 1-PP/MM was successfully achieved by chiral-phase highperformance liquid chromatography（HPLC）, and 1-PP and 1-MM were characterized by circular dichroism. Interestingly, it was found that 1-PP/MM could be completely isomerized to 1-PM upon heating, and the detailed thermodynamics and kinetics of the isomerization process were systematically investigated. 1-PM exhibited deep-red luminescence with emission maximum at 723 nm and fluorescence quantum yield as high as 32.95%. Consequently, we can showcase the lasing application of 1-PM by doping with epoxy resin to assemble a bottle microlaser spontaneously, which the lasing wavelength is 796.6 nm at a threshold of 0.8 m J cm-2. We believe that our studies, including the facile synthesis methodology, detailed isomerization studies, and lasing application, will shed some light on the design and synthesis of novel carbohelical systems with more functions.

关键词： double carbohelicene optical resolution organic laser isomerization X-ray diffraction

Frequent Trajectory Patterns Mining for Intelligent Visual Surveillance System

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Journal of Donghua University(English Edition) 2009年第2期26卷 164-170页

作者：曲琳陈耀武 inst.tute of advanced digital technology and instrument Zhejiang University

A frequent trajectory patterns mining algorithm is proposed to learn the object activities and classify the trajectories in intelligent visual surveillance *** distribution patterns of the trajectories were generated by an Apriori based frequent patterns mining algorithm and the trajectories were classified by the frequent trajectory patterns *** addition,a fuzzy c-means(FCM)based learning algorithm and a mean shift based clustering procedure were used to construct the representation of *** algorithm can be further used to describe activities and identify *** experiments on two real scenes show that the algorithm is effective.

关键词： trajectory classification visual surveillance mean shift trajectory pattern mining

Content based error resilience coding using redundant coding, reference frame modification, and mode decision

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Journal of Central South University 2014年第11期21卷 4199-4209页

作者：徐巍炜蒋荣欣田翔陈耀武 inst.tute of advanced digital technology and instrument Zhejiang University Zhejiang Provincial Key Laboratory for Network Multimedia Technologies (Zhejiang University)

Quality degradation occurs during transmission of video streaming over the error-prone network. By jointly using redundant slice, reference frame selection, and intra/inters mode decision, a content and end-to-end rate-distortion based error resilience method is proposed. Firstly, the intra/inter mode decision is implemented using macro-block(MB) refresh, and then redundant picture and reference frame selection are utilized together to realize the redundant coding. The estimated error propagation distortion and bit consumption of refresh MB are used for the mode and reference frame decision of refresh MB. Secondly, by analyzing the statistical property in the successive frames, the error propagation distortion and bit consumption are formulated as a function of temporal distance. Encoding parameters of the current frame is determined by the estimated error propagation distortion and bit consumption. Thirdly, by comparing the rate-distortion cost of different combinations, proper selection of error resilience method is performed before the encoding process of the current frame. Finally, the MB mode and bit distribution of the primary picture are analyzed for the derivation of the texture information. The motion information is subsequently incorporated for the calculation of video content complexity to implement the content based redundant coding. Experimental results demonstrate that the proposed algorithm achieves significant performance gains over the LA-RDO and HRP method when video is transmitted over error-prone channel.

关键词： error resilience coding redundant picture macro-block(MB) refresh reference frame selection error propagation distortion

SIMULATION OF ELECTRICAL FIELD FOR THE FORMATION MECHANISM OF BIRD'S NEST PATTERNED STRUCTURES BY ELECTROSPINNING

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Chinese Journal of Polymer Science 2013年第3期31卷 514-520页

作者： Xiang-yu Ye Yi-ning Jin Xiao-jun Huang Lei Luo 徐志康 MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang University inst.tute of advanced digital technology and instrument Zhejiang University

In our previous work, it was found that large electrospun from chlorinated polypropylene solution doped Bird＇s Nest patterned nanofibrous membranes can be simply with an ionic liquid, and a plausible formation mechanism of Bird＇s Nest patterned architectures was proposed. Here, we use Ansoft Maxwell version 12 software （3D, electrostatic solver） to simulate the electrical field distribution of the electrospinning setup, and to clarify the rationality of proposed formation mechanism. Calculation results clearly show that the introduction of charged nanofibrous bundles would produce a similar patterned electrical field distribution, which definitely confirms the important role of surface residual charges. The proposed mechanism can be well extended to other polymer systems including polystyrene, poly（acrylonitrile-co-acrylic acid） and chitosan/poly（ethylene oxide）.

关键词： Electrospinning Patterned structures Finite element analysis Electrical field Theoretical simulation.

Error Resilient Video Communication Based on Picture Level Adaptive Frame / Field Coding

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Journal of Donghua University(English Edition) 2013年第2期30卷 103-109页

作者：徐巍炜周凡陈耀武 inst.tute of advanced digital technology and instrument Zhejiang University Zhejiang Provincial Key Laboratory for Network Multimedia Technologies Zhejiang University

Packet loss protection method based on picture level adaptive frame /field coding (PAFF)was presented. Firstly,the end-to-end rate-distortion analysis for PAFF on the current frame was performed. Secondly,in order to evaluate the severity of error propagation in the following frames,the error propagation intensity and human visual quality sensitivity of different areas were taken into consideration. It was followed by the quantification of relative importance. Finally,the proper coding mode was chosen utilizing an unequal comparison procedure. The simulation results show that the proposed method can improve peak signal-to-noise ratio (PSNR) up to 0. 9 dB and 1. 6 dB comparing with the field only and the dispersed flexible macro-block ordering (FMO)only methods respectively.

关键词： error resilience field coding adaptive frame/field coding human visual system error control coding

Design and simulation of an accelerometer based on NV center spin–strain coupling

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Chinese Physics B 2024年第1期33卷 192-198页

作者：季鲁敏赵立业王裕海 Key Laboratory of Micro-Inertial instrument and advanced Navigation technology Ministry of EducationDepartment of Instrument Science and EngineeringSoutheast UniversityNanjing 210096China

The nitrogen-vacancy (NV) center quantum systems have emerged as versatile tools in the field of precision measurement because of their high sensitivity in spin state detection and miniaturization potential as solid-state *** this paper,an acceleration sensing scheme based on NV spin–strain coupling is proposed,which can effectively eliminate the influence of the stray noise field introduced by traditional mechanical *** the finite element simulation,it is found that the measurement bandwidth of this ensemble NV spin system ranges from 3 kHz to hundreds of kHz with structure√*** required power is at the sub-μW level,corresponding to a noise-limited sensitivity of 6.7×10^(-5) /√*** with other types of accelerometers,this micro-sized diamond sensor proposed here has low power consumption,exquisite sensitivity,and integration *** research opens a fresh perspective to realize an accelerometer with appealing comprehensive performance applied in biomechanics and inertial measurement fields.

关键词： nitrogen-vacancy(NV)accelerometer spin–strain diamond

Beyond Performance of Learning Control Subject to Uncertainties and Noise: A Frequency-Domain Approach Applied to Wafer Stages

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IEEE/CAA Journal of Automatica Sinica 2025年第1期 198-214页

作者： Fazhi Song Ning Cui Shuaiqi Chen Kai Zhang Yang Liu Xinkai Chen Jiubin Tan IEEE the Center of Ultra-precision Optoelectronic instrument Engineering Harbin Institute of Technology the Key Laboratory of Ultra-Precision Intelligent instrumentation Ministry of Industry and Information Technology the State Key Laboratory of Precision Electronic Manufacturing technology and Equipment Guangdong University of Technology the Center of Ultraprecision Optoelectronic instrument Engineering Harbin Institute of Technology the Key Laboratory of UltraPrecision Intelligent instrumentation Ministry of Industry and Information Technology the Department of Electronic and Information Systems Shibaura Institute of Technology

The increasingly stringent performance requirement in integrated circuit manufacturing, characterized by smaller feature sizes and higher productivity, necessitates the wafer stage executing a extreme motion with the accuracy in terms of nanometers. This demanding requirement witnesses a widespread application of iterative learning control(ILC), given the repetitive nature of wafer scanning. ILC enables substantial performance improvement by using past measurement data in combination with the system model knowledge. However, challenges arise in cases where the data is contaminated by the stochastic noise, or when the system model exhibits significant uncertainties, constraining the achievable performance. In response to this issue, an extended state observer(ESO) based adaptive ILC approach is proposed in the frequency *** being model-based, it utilizes only a rough system model and then compensates for the resulting model uncertainties using an ESO, thereby achieving high robustness against.uncertainties with minimal modeling effort. Additionally, an adaptive learning law is developed to mitigate the limited performance in the presence of stochastic noise, yielding high convergence accuracy yet without compromising convergence speed. Simulation and experimental comparisons with existing model-based and data-driven inversion-based ILC validate the effectiveness as well as the superiority of the proposed method.

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Recent advances in photonic crystal with unique structural colors:A review

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Journal of Materials Science & technology 2023年第10期141卷 78-99页

作者： Keming Zhu Changqing Fang Mengyuan Pu Jing Song Dong Wang Xing Zhou School of Mechanical and Precision instrument Engineering Xi’an University of TechnologyXi’an 710048China Faculty of Printing Packaging Engineering and Digital Media TechnologyXi’an University of TechnologyXi’an 710048China

Inspired by special color-forming organisms in nature,photonic crystal materials with structural color function have been developed significantly with great potential applications for displays,sensors,anti-counterfeiting inks,*** review aims to summarize the functions,self-assembly modes,and ap-plications of different kinds of photonic crystal *** preparation methods and characteristics of monodisperse inorganic nanoparticles,polymer nanoparticles,inorganic/organic core-shell nanoparti-cles,and MOFs are ***,we summarize the method of assembling colloidal parti-cles into photonic crystals,which is a template induction method,inkjet printing method,drop coating method,***,the potential application of structural color is presented including humidity re-sponse and magnetic field response in sensors fields,as well as the advantages and disadvantages of anti-counterfeiting,fabric coloring,displays,smart windows,and Biomedical ***,we present the development prospects and key problems of photonic crystals.

关键词： Photonic crystal Structural color Self-assembly Monodisperse nanoparticles Patterned nanostructures

First observation results of Macao Science Satellite-1 on lightning-induced electron precipitation

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Science China Earth Sciences 2025年第1期68卷 1-10页

作者： Yongping WANG Yixin SUN Qiugang ZONG Gaopeng LU Xudong GU Ze-Jun HU Bin LI Key Laboratory for Polar Science Ministry of Natural Resources Polar Research Institute of China inst.tute of Space Physics and Applied technology Peking University State Key Laboratory of Lunar and Planetary Science Macau University of Science and Technology School of Earth and Space Sciences University of Science and Technology of China School of Electronic Information Wuhan University

The Medium-energy Electron Spectrometers(MES) is a space-borne instrument onboard Macao Science Satellite-1(MSS-1) dedicated to monitoring the typical charged particle radiation characteristics in the satellite orbit and the process of their occurrence and development, including short bursts of lightning-induced electron precipitation(LEP).This paper presents the first results of the LEP measurements by the MSS-1.47 LEP events are identified with the routine operation for 3 months since satellite launch, all within the range of 1.5

关键词： Lightning-induced electron precipitation Inner radiation belts Energetic electrons Macao Science Satellite-1