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Experimental quantum secure network with digital signatures and encryption

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National Science Review 2023年第4期10卷 86-96页

作者： Hua-Lei Yin Yao Fu chen-long li chen-Xun Weng Bing-Hong li Jie Gu Yu-Shuo Lu Shan Huang Zeng-Bing chen National Laboratory of Solid State Microstructures School of Physics Collaborative Innovation Center of Advanced Microstructures Nanjing University MatricTime Digital Technology Co.Ltd.

Cryptography promises four information security objectives, namely, confidentiality, integrity, authenticity and non-repudiation, to support trillions of transactions annually in the digital economy. Efficient digital signatures, ensuring integrity, authenticity and non-repudiation of data with information-theoretical security are highly urgent and intractable open problems in cryptography. Here, we propose a high-efficiency quantum digital signature(QDS) protocol using asymmetric quantum keys acquired via secret sharing, one-time universal2hashing and a one-time pad. We just need to use a 384-bit key to sign documents of lengths up to 264with a security bound of 10-19. If a one-megabit document is signed, the signature efficiency is improved by more than 108times compared with previous QDS protocols.Furthermore, we build the first all-in-one quantum secure network integrating information-theoretically secure communication, digital signatures, secret sharing and conference key agreement and experimentally demonstrate this signature efficiency advantage. Our work completes the cryptography toolbox of the four information security objectives.

关键词： quantum digital signature information-theoretical security secret sharing one-time universal2 hashing cryptography toolbox

Catalytic Enantioselective Construction of 6-4 Ring-Junction All-Carbon Stereocenters and Mechanistic Insights

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Chinese Journal of Chemistry 2022年第15期40卷 1767-1776页

作者： Jia-Yin Wang chen-long li Ting Xu Meng-Fan li Wen-Juan Hao Shu-Jiang Tu Jianyi Wang Guigen li Zhi-Xiang Yu Bo Jiang School of Chemistry&Materials Science Jiangsu Normal UniversityXuzhouJiangsu 221116China College of Chemistry Peking UniversityBeijing 100871China Medical College Guangxi UniversityNanningGuangxi 530004China Institute of Chemistry&Biomedical Sciences Nanjing UniversityNanjingJiangsu 210093China Department of Chemistry and Biochemistry Texas Tech UniversityLubbockTexas 79409-1061United States

Comprehensive Summary Developing reactions for the synthesis of 6-6-4 and 6-4 carbocyclic scaffolds with a chiral quaternary center at the bridgehead position is highly desired,considering the existence of such skeletons in natural products with biological activities and the potential of using these molecules for downstream studies in chemical biology and medicinal chemistry.Report here is accessing these target skeletons with high chemo-,regio-and enantio-selectivities through Pd(ll)/chiral N,N'-disulfonyl bisimidazoline(Bim)ligand-catalyzed asymmetric reaction of yne-allenones and arylboronic acids.

关键词： Asymmetric catalysis Palladium Michael addition Chiral cyclobutenes Mechanism

Ynamide Protonation-Initiated Cis-Selective Polyene Cyclization and Reaction Mechanism

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CCS Chemistry 2022年第9期4卷 2991-3001页

作者： Jiasheng Yao chen-long li Xing Fan Zhou Wang Zhi-Xiang Yu Junfeng Zhao School of Pharmaceutical Sciences Guangzhou Medical UniversityGuangzhou 511436 College of Chemistry and Chemical Engineering Jiangxi Normal UniversityNanchang 330022 College of Chemistry Peking UniversityBeijing 100871 School of Chemistry and Chemical Engineering Northwestern Polytechnical UniversityXi’an 710072 State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071

The diastereoselectivity of conventional polyene cyclization reactions is highly dependent on the configuration of the internal alkenes,where E-poly enes provide trans-decalins,while Z-polyenes offer cis-decalins.Although polyene cyclization has evolved into a reliable and widely used strategy for the construction of trans-decalin frameworks of terpene and steroid natural products,its application for cis-decalin framework is extremely challenging.

关键词： polyene cyclization cis-decalin framework ynamide protonation double protonation mechanism

Deep Video Harmonization by Improving Spatial-temporal Consistency

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Machine Intelligence Research 2024年第1期21卷 46-54页

作者： Xiuwen chen li Fang long Ye Qin Zhang Key Laboratory of Media Audio and Video Ministry of Education Communication University of ChinaBeijing 100024China

Video harmonization is an important step in video editing to achieve visual consistency by adjusting foreground appear-ances in both spatial and temporal dimensions.Previous methods always only harmonize on a single scale or ignore the inaccuracy of flow estimation,which leads to limited harmonization performance.In this work,we propose a novel architecture for video harmoniza-tion by making full use of spatiotemporal features and yield temporally consistent harmonized results.We introduce multiscale harmon-ization by using nonlocal similarity on each scale to make the foreground more consistent with the background.We also propose a fore-ground temporal aggregator to dynamically aggregate neighboring frames at the feature level to alleviate the effect of inaccurate estim-ated flow and ensure temporal consistency.The experimental results demonstrate the superiority of our method over other state-of-the-art methods in both quantitative and visual comparisons.

关键词： Harmonization temporal consistency video editing video composition nonlocal similarity

An Environment‑Tolerant Ion‑Conducting Double‑Network Composite Hydrogel for High‑Performance Flexible Electronic Devices

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Nano-Micro Letters 2024年第5期16卷 352-369页

作者： Wenchao Zhao Haifeng Zhou Wenkang li Manlin chen Min Zhou long Zhao State Key Laboratory of Advanced Electromagnetic Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074People’s Republic of China School of Chemistry and Chemical Engineering Huazhong University of Science and TechnologyWuhan 430074People’s Republic of China

High-performance ion-conducting hydrogels(ICHs)are vital for developing flexible electronic devices.However,the robustness and ion-conducting behavior of ICHs deteriorate at extreme tempera-tures,hampering their use in soft electronics.To resolve these issues,a method involving freeze–thawing and ionizing radiation technology is reported herein for synthesizing a novel double-network(DN)ICH based on a poly(ionic liquid)/MXene/poly(vinyl alcohol)(PMP DN ICH)system.The well-designed ICH exhibits outstanding ionic conductivity(63.89 mS cm^(-1) at 25℃),excellent temperature resistance(-60–80℃),prolonged stability(30 d at ambient temperature),high oxidation resist-ance,remarkable antibacterial activity,decent mechanical performance,and adhesion.Additionally,the ICH performs effectively in a flexible wireless strain sensor,thermal sensor,all-solid-state supercapacitor,and single-electrode triboelectric nanogenerator,thereby highlighting its viability in constructing soft electronic devices.The highly integrated gel structure endows these flexible electronic devices with stable,reliable signal output performance.In particular,the all-solid-state supercapacitor containing the PMP DN ICH electrolyte exhibits a high areal specific capacitance of 253.38 mF cm^(-2)(current density,1 mA cm^(-2))and excellent environmental adaptability.This study paves the way for the design and fabrication of high-performance mul-tifunctional/flexible ICHs for wearable sensing,energy-storage,and energy-harvesting applications.

关键词： Ionic liquids Double-network hydrogels Temperature tolerance Multifunctionality Flexible electronic devices

Geometric phase-encoded stimuli-responsive cholesteric liquid crystals for visualizing real-time remote monitoring:humidity sensing as a proof of concept

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light(Science & Applications) 2024年第2期13卷 283-293页

作者： Shi-long li Zhao-Yi chen Peng chen Wei Hu Chaohong Huang Sen-Sen li Xuejia Hu Yan-Qing Lu Lu-Jian chen Department of Electronic Engineering School of Electronic Science and EngineeringXiamen University361005 XiamenChina College of Engineering and Applied Sciences Nanjing University210093 NanjingChina Fujian Key Laboratory of Ultrafast Laser Technology and Applications Xiamen University361005 XiamenChina

liquid crystals are a vital component of modern photonics,and recent studies have demonstrated the exceptional sensing properties of stimuli-responsive cholesteric liquid crystals.However,existing cholesteric liquid crystal-based sensors often rely on the naked eye perceptibility of structural color or the measurement of wavelength changes by spectrometric tools,which limits their practical applications.Therefore,developing a platform that produces recognizable sensing signals is critical.In this study,we present a visual sensing platform based on geometric phase encoding of stimuli-responsive cholesteric liquid crystal polymers that generates real-time visual patterns,rather than frequency changes.To demonstrate this platform’s effectiveness,we used a humidity-responsive cholesteric liquid crystal polymer film encoded with a q-plate pattern,which revealed that humidity causes a shape change in the vortex beam reflected from the encoded cholesteric liquid crystal polymers.Moreover,we developed a prototype platform towards remote humidity monitoring benefiting from the high directionality and long-range transmission properties of laser beams carrying orbital angular momentum.Our approach provides a novel sensing platform for cholesteric liquid crystals-based sensors that offers promising practical applications.The ability to generate recognizable sensing signals through visual patterns offers a new level of practicality in the sensing field with stimuli-responsive cholesteric liquid crystals.This platform might have significant implications for a broad readership and will be of interest to researchers working in the field of photonics and sensing technology.

关键词： humidity visual liquid

Dynamic Event-Triggered Consensus Control for Input Constrained Multi-Agent Systems With a Designable Minimum Inter-Event Time

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 649-660页

作者： Meilin li Yue long Tieshan li Hongjing liang C.L.Philip chen the School of Automation Engineering University of Electronic Science and Technology of ChinaChengdu 611731China IEEE the Yangtze Delta Region Institute University of Electronic Science and Technology of ChinaHuzhou 313000 the Laboratory of Electromagnetic Space Cognition and Intelligent Control Beijing 100089China the School of Computer Science and Engineering South China University of TechnologyGuangzhou 510006

This paper investigates the consensus control of multi-agent systems(MASs) with constrained input using the dynamic event-triggered mechanism(ETM).Consider the MASs with small-scale networks where a centralized dynamic ETM with global information of the MASs is first designed.Then,a distributed dynamic ETM which only uses local information is developed for the MASs with large-scale networks.It is shown that the semi-global consensus of the MASs can be achieved by the designed bounded control protocol where the Zeno phenomenon is eliminated by a designable minimum inter-event time.In addition,it is easier to find a trade-off between the convergence rate and the minimum inter-event time by an adjustable parameter.Furthermore,the results are extended to regional consensus of the MASs with the bounded control protocol.Numerical simulations show the effectiveness of the proposed approach.

关键词： Constrained input designable minimum inter-event time directed communication topology dynamic event-triggered mechanism MASs consensus control

Recent advances and perspectives in MXene-based cathodes for aqueous zinc-ion batteries

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1752-1765页

作者： Aiduo Wu Tianhao Wang long Zhang chen chen Qiaomin li Xuanhui Qu Yongchang liu Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyState Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China School of Economics and Management University of Science and Technology BeijingBeijing 100083China

Aqueous zinc-ion batteries(AZIBs)show great potential for applications in grid-scale energy storage,given their intrinsic safety,cost effectiveness,environmental friendliness,and impressive electrochemical performance.However,strong electrostatic interactions exist between zinc ions and host materials,and they hinder the development of advanced cathode materials for efficient,rapid,and stable Zn-ion storage.MXenes and their derivatives possess a large interlayer spacing,excellent hydrophilicity,outstanding electronic conductivity,and high redox activity.These materials are considered“rising star”cathode candidates for AZIBs.This comprehensive review discusses recent advances in MXenes as AZIB cathodes from the perspectives of crystal structure,Zn-storage mechanism,surface modification,interlayer engineering,and conductive network design to elucidate the correlations among their composition,structure,and electrochemical performance.This work also outlines the remaining challenges faced by MXenes for aqueous Zn-ion storage,such as the urgent need for improved toxic preparation methods,exploration of potential novel MXene cathodes,and suppression of layered MXene restacking upon cycling,and introduces the prospects of MXene-based cathode materials for high-performance AZIBs.

关键词： aqueous zinc-ion batteries MXenes terminal groups interlayer engineering conductive network design

China’s Proactive Fiscal Policy

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China Economist 2024年第1期19卷 58-74页

作者： Xing li chen long Chinese Academy of Fiscal Sciences BeijingChina

In contrast to the traditional Western approach to macro-fiscal management,China’s proactive fiscal policy is founded on a people-centered development philosophy and,with distinctive Chinese characteristics,is a significant policy innovation of macroeconomic management in the Chinese modernization.Although there are notable distinctions between the Western“Keynesian”and the“nonKeynesian”schools of thought,both of these approaches’core policy goals and methodological roots are the same,composing the traditional Western macro-fiscal approach.This approach faces increasing real dilemmas.China’s proactive fiscal policy,however,places greater emphasis on future potential growth rates in addition to equilibrium between supply and demand,achieving a fiscal policy transformation with a new approach.In this paper we argue that with such a new approach,China should reconsider the nature and reasonable level of the fiscal deficit,the function and risk assessment criteria of government debt,the scope and effects of reductions in taxes and fees,its approach and focus of demand management,and the costs and resulting efficiencies of policies in order to develop a new fiscal policy paradigm that is more in line with its stated goals.

关键词： Proactive fiscal policy fiscal approach potential growth rate