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Miniaturized and highly sensitive fiber-optic Fabry–Perot sensor for mHz infrasound detection

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Photonics Research 2024年第5期12卷 969-978页

作者： PEIJIE WANG YUFENG PAN JIANGSHAN ZHANG JIE ZHAI DEMING LIU PING LU Wuhan National Laboratory for Optoelectronics(WNLO)and National Engineering Research Center of next generation Internet access System School of Optical and Electronic InformationHuazhong University of Science and TechnologyWuhan 430074China Optics Valley Laboratory Wuhan 430074China Department of Electronics and Information Engineering Huazhong University of Science and TechnologyWuhan 430074China

Infrasound detection is important in natural disasters monitoring,military defense,underwater acoustic detection,and other ***-optic Fabry–Perot(FP)acoustic sensors have the advantages of small structure size,long-distance detection,immunity to electromagnetic interference,and so *** size of an FP sensor depends on the transducer diaphragm size and the back cavity ***,a small transducer diaphragm size means a low ***,a small back cavity volume will increase the low cut-off frequency of the ***,it is difficult for fiber-optic FP infrasound sensors to simultaneously achieve miniaturization,high sensitivity,and extremely low detectable *** this work,we proposed and demonstrated a miniaturized and highly sensitive fiber-optic FP sensor for m Hz infrasound detection by exploiting a Cr-Ag-Au composite acoustic-optic transducer diaphragm and a MEMS technique-based spiral micro-flow *** use of the spiral micro-flow hole as the connecting hole greatly reduced the volume of the sensor and decreased the low-frequency limit,while the back cavity volume was not *** with the Cr-Ag-Au composite diaphragm,a detection sensitivity of-123.19 dB re 1 rad∕μPa at 5 Hz and a minimum detectable pressure(MDP)of1.2 mPa∕Hz^(1∕2)at 5 Hz were *** low detectable frequency can reach 0.01 Hz and the flat response range was 0.01–2500 Hz with a sensitivity fluctuation of±1.5 d ***,the size of the designed sensor was only 12 mm×Φ12.7 *** excellent characteristics make the sensor have great practical application prospects.

关键词： sound fiber cavity

Energy-Function Based Pilot Protection Scheme for Hybrid UHVDC Transmission Applying Improved Hausdorff Distance

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 891-902页

作者： Zijiang Wang Youping Fan Ben Shang Yinbiao Shu School of Electrical Engineering and Automation Wuhan UniversityWuhan 430072China Institute of next generation Power Systems&International Standards Wuhan UniversityWuhan 430072China CSEE IEEE

A hybrid UHVDC transmission system applying LCC as the rectifier and MMC as the inverter combines the advantages of both converter types,which makes this protection scheme more complicated.A new pilot protection scheme for a three-terminal hybrid DC transmission system applying energy functions is *** energy function for LCC is applied to MMC to derive the energy level of the hybrid ***,an improved Hausdorff distance(IHD)algorithm is proposed to detect the difference in energy levels between the normal and fault *** abrupt change in energy level is characterized by IHD change *** points at which the IHD change rate exceeds the threshold at converter stations are applied to determine the fault line and to estimate the fault *** proposed protection scheme is then verified by a simulation model of the Wudongde±800 kV three-terminal hybrid UHVDC transmission *** appropriate sampling frequency is selected for a real-time calculation,and the threshold is selected considering the effect of *** show the proposed scheme can identify and trip fault lines quickly and effectively,even for a 600Ωgrounding *** waveshape similarity algorithms are compared and *** with existing protection schemes,the proposed scheme transmits less data to improve communication speed and reliability.

关键词： Energy function Hausdorff distance pilot protection UHVDC transmission

Efficient capture of difluorocarbene by pyridinium 1,4-zwitterionic thiolates:A concise synthesis of difluoromethylene-containing 1,4-thiazine derivatives

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Chinese Chemical Letters 2024年第4期35卷 367-370页

作者： Zhiwei Chen Heyun Sheng Xue Li Menghan Chen Xin Li Qiuling Song Institute of next generation Matter Transformation College of Materials Science&Engineering and College of Chemical Engineering at Huaqiao UniversityXiamen 361021China Fujian University Key Laboratory of Molecule Synthesis and Function Discovery College of ChemistryFuzhou UniversityFuzhou 350108China State Key Laboratory of Organometallic Chemistry and Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

A practical method for the construction of difluoromethylene-containing 1,4-thiazine moieties using readily available diethyl bromodifluoromethanephosphonate(BrCF_(2)PO(OEt)_(2))as difluorocarbene precusor has been *** transformation features the efficient capture of difluorocarbene by pyridinium 1,4-zwitterionic thiolates.A series of structurally novel and functionalized difluoromethylene-containing 1,4-thiazine derivatives were thus synthesized in good yields.

关键词： Difluoromethylene Pyridinium 1 4-zwitterionic thiolates 1 4-Thiazine derivatives

Safer solid-state lithium metal batteries:Mechanisms and strategies

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InfoMat 2024年第2期6卷 1-27页

作者： Shi-Jie Yang Jiang-Kui Hu Feng-Ni Jiang Hong Yuan Ho Seok Park Jia-Qi Huang School of Materials Science&Engineering Beijing Institute of TechnologyBeijingthe People's Republic of China Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijingthe People's Republic of China College of Chemical Engineering and Technology Taiyuan University of TechnologyTaiyuanShanxithe People's Republic of China Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijingthe People's Republic of China Center for next-generation Energy Materials and School of Chemical Engineering Sungkyunkwan UniversitySuwonRepublic of Korea

Solid-state batteries that employ solid-state electrolytes(SSEs)to replace routine liquid electrolytes are considered to be one of the most promising solutions for achieving high-safety lithium metal *** with high mechanical modulus,thermal stability,and non-flammability can not only inhibit the growth of lithium dendrites but also enhance the safety of lithium metal ***,several internal materials/electrodes-related thermal hazards demonstrated by recent works show that solid-state lithium metal batteries(SSLMBs)are not ***,understanding the potential thermal hazards of SSLMBs is critical for their more secure and widespread *** this contribution,we provide a comprehensive overview of the thermal failure mechanism of SSLMBs from materials to ***,strategies to improve the thermal safety performance of SSLMBs are included from the view of material enhancement,battery design,and external ***,the future directions are further *** hope that this work can shed bright insights into the path of constructing energy storage devices with high energy density and safety.

关键词： lithium metal batteries safety improvements solid-state batteries thermal failures thermal runaway

Probing the electric double layer structure at nitrogen-doped graphite electrodes by constant-potential molecular dynamics simulations

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Journal of Energy Chemistry 2024年第6期93卷 299-305,I0008页

作者： Legeng Yu Nan Yao Yu-Chen Gao Zhong-Heng Fu Bo Jiang Ruiping Li Cheng Tang Xiang Chen Tsinghua Center for Green Chemical Engineering Electrification(CCEE) Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China National Materials Corrosion and Protection Data Center University of Science and Technology BeijingBeijing 100083China Ordos Carbon Neutral Research and Application Co. Ltd.Ordos 017010Inner Mongoli1China Institute for Carbon Neutrality Tsinghua UniversityBeijing 100084China Center for next-generation Energy Materials and School of Chemical Engineering Sungkyunkwan University2066 Seobu-roJangan-guSuwon-siGyeonggi-do 16419Republic of Korea

Electric double layer(EDL)is a critical topic in electrochemistry and largely determines the working performance of lithium ***,atomic insights into the EDL structures on heteroatom-modified graphite anodes and EDL evolution with electrode potential are very ***,a constant-potential molecular dynamics(CPMD)method is proposed to probe the EDL structure under working conditions,taking N-doped graphite electrodes and carbonate electrolytes as an *** interface model was developed,incorporating the electrode potential and atom *** a result,an insightful atomic scenario for the EDL structure under varied electrode potentials has been established,which unveils the important role of doping sites in regulating both the EDL structures and the following electrochemical reactions at the atomic ***,the negatively charged N atoms repel the anions and adsorb Li~+at high and low potentials,*** preferential adsorption suggests that Ndoped graphite can promote Li~+desolvation and regulate the location of Li~+*** CPMD method not only unveils the mysterious function of N-doping from the viewpoint of EDL at the atomic level but also applies to probe the interfacial structure on other complicated electrodes.

关键词： Lithium batteries Graphite N-doping Electric double layer Molecular dynamics Constant potential method Electrode potential

Optical Microfber Neuron for Finger Motion Perception

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Advanced Fiber Materials 2022年第2期4卷 226-234页

作者： Yanpeng Li Shijie Tan Liuyang Yang Liangye Li Fang Fang Qizhen Sun School of Optical and Electronic Information National Engineering Laboratory for Next Generation Internet Access SystemHuazhong University of Science and TechnologyWuhan 430074HubeiChina

To achieve dexterous motion controlling of robot,the sensors that function like human neurons for motion perception are *** this work,a silica microfber probe-based optical neuron(MPON)for robot fnger motion detection is *** silica microfber probe was fabricated by snapping a biconical silica optical microfber that drawn from the standard optical *** it was embedded into thin polydimethylsiloxane(PDMS)to detect and recognize motions of robotic ***,a PDMS-Tefon-Microfber-Tefon-PDMS composite structure was prepared to protect the waveguide structure of silica microfber probe and avoid the environmental *** the help of this composite structure,the proposed MPON achieved the accurate measurement of bending angle with large range and fast *** repeatability and stability of MPON were also ***,diferent fnger motions were successfully distinguished through observing the output power variation of *** proposed MPON could serve as the perceptron of robot hand,which could be applied in dexterous gesture control even human machine interaction.

关键词： Optical neuron Silica microfber probe,fnger motion detection

A three-way electrolyte with ternary solvents for high-energy-density and long-cycling lithium-sulfur pouch cells

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SusMat 2024年第2期4卷 1-12页

作者： Zheng Li Legeng Yu Chen-Xi Bi Xi-Yao Li JinMa Xiang Chen Xue-Qiang Zhang Aibing Chen Haoting Chen Zuoru Zhang Li-Zhen Fan Bo-Quan Li Cheng Tang Qiang Zhang Tsinghua Center for Green Chemical Engineering Electrification Beijing Key Laboratory of Green Chemical Reaction Engineering and TechnologyDepartment of Chemical EngineeringTsinghua UniversityBeijingChina School of Materials Science and Engineering Beijing Institute of TechnologyBeijingChina Institute of Advanced Materials and Technology University of Science and TechnologyBeijingChina Shanxi Research Institute for Clean Energy Tsinghua UniversityTaiyuanChina Center for next-generation Energy Materials and School of Chemical Engineering Sungkyunkwan UniversityJangan-GuSuwon-SiGyeonggi-DoRepublic of Korea College of Chemical and Pharmaceutical Engineering Hebei University of Science and TechnologyShijiazhuangChina Ordos Carbon Neutral Research and Application Co. Ltd.Kangbashi DistrictOrdos CityInner MongoliaChina Institute for Carbon Neutrality Tsinghua UniversityBeijingChina

Lithium–sulfur(Li–S)batteries promise high-energy-density potential to exceed the commercialized lithiumion batteries but suffer from limited cycling lifespan due to the side reactions between lithium polysulfides(LiPSs)and Li metal ***,a three-way electrolyte with ternary solvents is proposed to enable high-energy-density and long-cycling Li–S pouch ***,ternary solvents composed of 1,2-dimethoxyethane,di-isopropyl sulfide,and 1,3,5-trioxane are employed to guarantee smooth cathode kinetics,inhibit the parasitic reactions,and construct a robust solid electrolyte interphase,*** cycling lifespan of Li–S coin cells with 50μm Li anodes and 4.0 mg cm^(−2) sulfur cathodes is prolonged from88 to 222 cycles using the three-way ***-heterogeneous solvation structure of LiPSs and organic-rich solid electrolyte interphase are identified to improve the cycling stability of Li metal ***,a 3.0 Ah-level Li–S pouch cell with the three-way electrolyte realizes a high energy density of 405 Wh kg^(−1) and undergoes 27 *** affords a three-way electrolyte recipe for suppressing the side reactions of LiPSs and inspires rational electrolyte design for practical high-energy-density and long-cycling Li–S batteries.

关键词： lithium metal anodes lithium-sulfur batteries pouch cells solid electrolyte interphase three-way electrolyte

Decoding the inconsistency of six cropland maps in China

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The Crop Journal 2024年第1期12卷 281-294页

作者： Yifeng Cui Ronggao Liu Zhichao Li Chao Zhang Xiao-Peng Song Jilin Yang Le Yu Mengxi Chen Jinwei Dong Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Department of Geographical Sciences University of MarylandCollege ParkMD 20740USA College of Grassland Science and Technology China Agricultural UniversityBeijing 100193China Ministry of Education Ecological Field Station for East Asian Migratory Birds Department of Earth System ScienceInstitute for Global Change StudiesTsinghua UniversityBeijing 100084China Ministry of Education Ecological Field Station for East Asian Migratory Birds Beijing 100084China Tsinghua University(Department of Earth System Science)-Xi’an Institute of Surveying and Mapping Joint Research Center for next-generation Smart Mapping Beijing 100084China Institute of Remote Sensing and Geographic Information System Peking UniversityBeijing 100871China Department of Forest and Conservation Sciences University of British ColumbiaVancouverBCV6T 1Z4Canada

Accurate cropland information is critical for agricultural planning and production,especially in foodstressed countries like *** widely used medium-to-high-resolution satellite-based cropland maps have been developed from various remotely sensed data sources over the past few decades,considerable discrepancies exist among these products both in total area and in spatial distribution of croplands,impeding further applications of these *** factors influencing their inconsistency are also *** this study,we evaluated the consistency and accuracy of six cropland maps widely used in China in circa 2020,including three state-of-the-art 10-m products(i.e.,Google Dynamic World,ESRI Land Cover,and ESA WorldCover)and three 30-m ones(i.e.,GLC_FCS30,GlobeLand 30,and CLCD).We also investigated the effects of landscape fragmentation,climate,and agricultural *** using a ground-truth sample revealed that the 10-m-resolution WorldCover provided the highest accuracy(92.3%).These maps collectively overestimated Chinese cropland area by up to 56%.Up to 37%of the land showed spatial inconsistency among the maps,concentrated mainly in mountainous regions and attributed to the varying accuracy of cropland maps,cropland fragmentation and management practices such as *** work shed light on the promotion of future cropland mapping efforts,especially in highly inconsistent regions.

关键词： Consistency and accuracy 10-and 30 m Cropland mapping Agricultural management China

Time-slot multiplexing based bandwidth enhancement for fiber distributed acoustic sensing

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Science China(Information Sciences) 2022年第1期65卷 292-293页

作者： Hao LI Cunzheng FAN Tao LIU Yujia LIU Zhijun YAN Perry SHUM Qizhen SUN National Engineering Laboratory for next generation Internet access System Wuhan National Laboratory for Optoelectronics School of Optical and Electronic InformationHuazhong University of Sicence and Technology Department of Electrical and Electronic Engineering Southern University of Science and Technology

Dear editor,The phase-sensitive optical time-domain reflectometry(φ-OTDR) has been demonstrated as the most common technique in fiber distributed acoustic sensing(DAS). However,traditional φ-OTDR based DAS suffered from the inherent trade-off between the maximum frequency response and the distance which can be characterized by distance bandwidth product(DBP), since the time interval of the probe pulses should be larger than the pulse round-trip flight time.

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