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Precise spectroscopy of metastable Li plus using the optical Ramsey technique in support of time dilation tests

PHOTONICS RESEARCH 2025年第1期13卷 201-209页

作者： zhou, peng-peng Chen, Shao-long Qin, Cheng-gang Chang, Xu-rui zhou, Zhi-qiang Sun, Wei Huang, Yao Gao, Ke-lin Guan, Hua Chinese Acad Sci Innovat Acad Precis Measurement Sci & Technol State Key Lab Magnet Resonance & Atom & Mol Phys Wuhan 430071 Peoples R China Informat Engn Univ Zhengzhou 450001 Peoples R China Chinese Acad Sci Key Lab Time Reference & Applicat Wuhan 430206 Peoples R China Huazhong Univ Sci & Technol MOE Key Lab Fundamental Phys Quant Measurement Wuhan 430074 Peoples R China Huazhong Univ Sci & Technol Hubei Key Lab Gravitat & Quantum Phys PGMF Wuhan 430074 Peoples R China Huazhong Univ Sci & Technol Sch Phys Wuhan 430074 Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China Chinese Acad Sci Qinghai Inst Salt Lakes Key Lab Green & High end Utilizat Salt Lake Resour Xining 810008 Peoples R China Wuhan Inst Quantum Technol Wuhan 430206 Peoples R China

Time dilation constitutes a crucial aspect of Lorentz invariance within special relativity and undergoes constant scrutiny through numerous Ives-Stilwell-type experiments employing the Doppler effect. In our study, we employed optical Ramsey spectroscopy on a Li+ ion beam to enhance the precision of measuring the intrinsic transition frequency 23S1 - 23P2 to the level of four parts in 1010 with speed of 0.00035c. Our findings reconciled an existing 2 MHz disparity between collinear and perpendicular laser spectroscopy. Furthermore, in conjunction with previous studies on Li+ ion beams traveling at speeds of 0.064c and 0.338c [Nat. Phys. 3, 861 (2007);Phys. Rev. Lett. 113, 120405 (2014)], we updated the Robertson-Mansouri-Sexl parameter alpha to be (-10.0 f 9.9) x 10-8 and (-2.9 f 2.0) x 10-8, respectively. (c) 2024 Chinese Laser Press

关键词： Doppler effect Frequency combs Laser beams Nodal aberration theory Optical clocks Optical fields

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Radiation synthesis and characteristics of PTFE-g-PSSA ion exchange membrane applied in vanadium redox battery

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Nuclear Science and Techniques 2007年第1期18卷 50-54页

作者： peng Jinfen QIU Jinyi NI Jiangfeng ZHAI Maolin XU peng peng Jing zhou Henghui LI Jiuqiang WEI Genshuan Beijing National Laboratory for Molecular Sciences Department of Applied Chemistry College of Chemistry ＆ Molecular Engineering Peking University Beijing 100871 China

Radiation-induced grafting of styrene onto polytetrafluoroethylene (PTFE) membranes was studied by a simultaneous irradiation *** was carded out usingγ-radiation from a ^(60)Co source at room temperature. Effects of absorbed dose,atmosphere,dose rate,and the concentration of initial monomer on the degree of grafting (DOG) were investigated and the most appropriate grafting condition was ***,sulphonation of the grafted PTFE membrane (PTFE-g-PS) was carried out and a series of ion exchange membranes (PTFE-g-PSSA) was *** characterizations of FTIR,TGA,and SEM testified that grafting and sulphonation of the membranes were successfully processed;moreover,grafting of styrene not only occurred in the surface of PTFE membrane,but also in the micropores of the *** exchange capacity (IEC) and conductivity were found increase with the grafting *** results suggest that at a low dose,such as 17 kGy,the ion exchange membrane (IEM) which will be suitable for vanadium redox battery (VRB) use can be obtained.

关键词： PTFE-g-PSSA离子交换膜辐射合成性质钒氧化还原电池

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Deceleration of Metastable Li^+ Beam by Combining Electrostatic Lens and Ion Trap Technique

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Chinese Physics Letters 2020年第7期37卷 15-18页

作者： Shao-Long Chen peng-peng zhou Shi-Yong Liang Wei Sun Huan-Yao Sun Yao Huang Hua Guan Ke-Lin Gao State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China Center for Cold Atom Physics Chinese Academy of SciencesWuhan 430071China

Ion deceleration has played a critical role in ion-related research when the ions are produced in the form of a high-energy *** present a deceleration method combining electrostatic lens and ion trap technique,which can effectively decelerate ions to energy below the trapping potential of a typical ion *** experiments were performed on metastable 1s2s3S1Li+ions,and demonstrated that the kinetic energy could easily be reduced from^450 e V to a few e V,with the latter being confirmed using the Doppler-shifted fluorescence spectra.

关键词： spectra. beam. latter

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Significantly Improving the Escape Time of a Single 40Ca+Ion in a Linear Paul Trap by Fast Switching of the Endcap Voltage

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Chinese Physics Letters 2020年第9期37卷 21-25页

作者： peng-peng zhou Shao-Long Chen Shi-Yong Liang Wei Sun Huan-Yao Sun Yao Huang Hua Guan Ke-Lin Gao State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China Center for Cold Atom Physics Chinese Academy of SciencesWuhan 430071China

Sympathetic cooling is a method used to lower the kinetic energy of ions with complicated energy-level structures,via Coulomb interactions with laser-cooled ions in an ion *** ion to be sympathetically cooled is sometimes prepared outside of the trap,and it is critical to introduce this ion into the trap by temporarily lowering the potential of one endcap without allowing the coolant ion to *** study the time required for a laser-cooled ion to escape from a linear Paul trap when the voltage of one endcap is *** escape time is on the order of a few microseconds,and varies significantly when the low-level voltage changes.A re-cooling time of a maximum of 13 s was measured,which can be reduced to approximately one hundred of milliseconds by decreasing the duration of the low-level *** measurement of these critical values lays the foundation for the smooth injection and cooling of the ion to be sympathetically cooled.

关键词： outside Paul critical

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Characteristics of groundwater in Northeast Qinghai-Tibet Plateau and its response to climate change and human activities:A case study of Delingha,Qaidam Basin

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China Geology 2021年第3期4卷 377-388页

作者： Wei Zhao Yan-zhu Lin peng-peng zhou Guang-cai Wang Xue-ya Dang Xiao-fan Gu China Institute of Geo-Environment Monitoring China Geological SurveyBeijing 100081China State Key Laboratory of Biogeology and Environmental Geology and MOE Key Laboratory of Groundwater Circulation and Environmental Evolution School of Water Resources and EnvironmentChina University of Geosciences(Beijing)Beijing 100083China Xi’an Center China Geological SurveyXi’an 710054China

Delingha is located in the northeast margin of Qaidam *** River alluvial proluvial fan is the main aquifer of Delingha,in which groundwater generally flows from north to *** hydrochemistry results showed that two different hydrochemical evolution paths formed along southeast and southwest directions,***-Na type groundwater was formed in front of Gahai Lake,and SO_(4)·HCO_(3)-Na·Ca type groundwater was formed in front of Keluke *** results of deuterium(D)and 18O revealed that the groundwater mainly originated from the continuous accumulation of precipitation during geological history under cold and humid climate *** addition,results of ^(14)C indicated that the groundwater age was more than 1140 years,implying relatively poor renewal capability of regional ***,our numerical modeling results showed that the regional groundwater level will continue to rise under the warm and humid climate conditions.

关键词： Groundwater Global climate change Hydrochemistry Groundwater circulation Groundwater age Groundwater level rising Geological survey engineering Qaidam Basin Delingha Qinghai-Tibet Plateau

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Multi boron-doping effects in hard carbon toward enhanced sodium ion storage

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Journal of Energy Chemistry 2025年第1期100卷 730-738页

作者： peng Zheng Wang zhou Ying Mo Biao Zheng Miaomiao Han Qin Zhong Wenwen Yang peng Gao Lezhi Yang Jilei Liu College of Materials Science and Engineering Hunan Joint International Laboratory of Advanced Materials and Technology for Clean EnergyHunan Province Key Laboratory for Advanced Carbon Materials and Applied TechnologyHunan UniversityChangsha 410082HunanChina Greater Bay Area Institute for Innovation Hunan UniversityGuangzhou 511300GuangdongChina Changsha Research Institute of Mining&Metallurgy Co. LTD.Changsha 410017HunanChina

Hard carbon (HC) has been considered as promising anode material for sodium-ion batteries (SIBs).The optimization of hard carbon’s microstructure and solid electrolyte interface (SEI) property are demonstrated effective in enhancing the Na+storage capability,however,a one-step regulation strategy to achieve simultaneous multi-scale structures optimization is highly ***,we have systematically investigated the effects of boron doping on hard carbon’s microstructure and interface chemistry.A variety of structure characterizations show that appropriate amount of boron doping can increase the size of closed pores via rearrangement of carbon layers with improved graphitization degree,which provides more Na+storage ***-situ Fourier transform infrared spectroscopy/electrochemical impedance spectroscopy (FTIR/EIS) and X-ray photoelectron spectroscopy (XPS) analysis demonstrate the presence of more BC3and less B–C–O structures that result in enhanced ion diffusion kinetics and the formation of inorganic rich and robust SEI,which leads to facilitated charge transfer and excellent rate *** a result,the hard carbon anode with optimized boron doping content exhibits enhanced rate and cycling *** general,this work unravels the critical role of boron doping in optimizing the pore structure,interface chemistry and diffusion kinetics of hard carbon,which enables rational design of sodium-ion battery anode with enhanced Na+storage performance.

关键词： Hard carbon Sodium-ion batteries Boron doping Pore structure Electrode/electrolyte interphases

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Development of a coupled model to simulate and assess arsenic contamination and impact factors in the Jinsha River Basin,China

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Journal of Environmental Sciences 2025年第1期147卷 50-61页

作者： Yidian Sun Xu Zhang Hong peng Wenting zhou Anna Jiang Feng zhou Hao Wang Wanshun Zhang School of Resource and Environmental Sciences Wuhan UniversityWuhan 430079China School of Water Conservancy and Hydropower Engineering Wuhan UniversityWuhan 430072China China Institute of Water Resources and Hydropower Research Beijing 100038China School of Water Resources and Hydropower State Key Laboratory of Water Resources and Hydropower Engineering ScienceWuhan UniversityWuhan 430072China

With the increasing severity of arsenic(As)pollution,quantifying the environmental behavior of pollutant based on numerical model has become an important approach to determine the potential impacts and finalize the precise control *** the industrialintensive Jinsha River Basin as typical area,a two-dimensional hydrodynamic water quality model coupled with Soil andWater Assessment Tool(SWAT)model was developed to accurately simulate the watershed-scale distribution and transport of As in the terrestrial and aquatic environment at high spatial and temporal *** effects of hydro-climate change,hydropower station construction and non-point source emissions on Aswere quantified based on the coupled *** result indicated that higher As concentration areas mainly centralized in urban districts and concentration slowly decreased from upstream to *** to the enhanced rainfall,the As concentration was significantly higher during the rainy season than the dry ***-climate change and the construction of hydropower station not only affected the dissolved As concentration,but also affected the adsorption and desorption of As in ***,As concentration increased with the input of non-point source pollution,with the maximum increase about 30%,resulting that non-point sources contributed important pollutant impacts to *** coupled model used in pollutant behavior analysis is generalwith high potential application to predict and mitigate water pollution.

关键词： Watershed system Arsenic Modeling Distribution Hydro-climate change Non-point source pollution

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Radical dehydroxymethylative fluorination of aliphatic primary alcohols and diverse functionalization ofα-fluoroimides via BF_(3)·OEt_(2)-catalyzed C-F bond activation

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Chinese Chemical Letters 2025年第1期36卷 239-243页

作者： peng Wang Jianjun Wang Ni Song Xin zhou Ming Li Molecular Synthesis Center Key Laboratory of Marine MedicineChinese Ministry of EducationSchool of Medicine and PharmacyOcean University of ChinaQingdao 266003China Laboratory for Marine Drugs and Bioproducts Pilot National Laboratory for Marine Science and TechnologyQingdao 266237China

Ag_(2)CO_(3)-promoted dehydroxymethylative fluorination of aliphatic alcohols has been achieved with Selectfluor as both oxidant and fluorine *** reaction involvesβ-fragmentation of primary alkoxy radicals,followed by the fluorination of the resulting C-centered radical *** transformation proceeds under mild reaction conditions and exhibits a broad substrate scope,thus opening up a new entrance to the synthesis of fluorinated constructs includingα-fluoroimides and 1-fluoroalkyl benzoates as well as secondary and tertiary alkyl fluorides like versatile 2-fluoro-2-alkyl 1,3-propandiol *** divergent functionalization of the obtainedα-fluoroimides enables an efficient access to amine derivatives through C-F bond activation under the action of BF_(3)·OEt_(2).

关键词： Dehydroxymethylative fluorination Alkoxy radicals β-Fragmentation Silver catalysis C-F Bond activation

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BEV-Locator:an end-to-end visual semantic localization network using multi-view images

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Science China(Information Sciences) 2025年第2期68卷 134-150页

作者： Zhihuang ZHANG Meng XU Wenqiang zhou Tao peng Liang LI Stefan POSLAD School of Vehicle and Mobility Tsinghua University School of Information Technology & Management University of International Business and Economics Qcraft Inc. School of Electronic Engineering and Computer Science Queen Mary University of London

Accurate localization ability is fundamental in autonomous driving. Traditional visual localization frameworks approach the semantic map-matching problem with geometric models, which rely on complex parameter tuning and thus hinder large-scale deployment. In this paper, we propose BEV-Locator: an end-to-end visual semantic localization neural network using multi-view camera images. Specifically, a visual BEV(bird-eye-view) encoder extracts and flattens the multi-view images into BEV space. While the semantic map features are structurally embedded as map query sequences. Then a cross-model transformer associates the BEV features and semantic map queries. The localization information of ego-car is recursively queried out by cross-attention modules. Finally, the ego pose can be inferred by decoding the transformer outputs. This end-to-end model speaks to its broad applicability across different driving environments, including high-speed scenarios. We evaluate the proposed method in large-scale nuScenes and Qcraft datasets. The experimental results show that the BEV-Locator is capable of estimating the vehicle poses under versatile scenarios, which effectively associates the cross-model information from multi-view images and global semantic maps. The experiments report satisfactory accuracy with mean absolute errors of 0.052 m, 0.135 m and 0.251° in lateral, longitudinal translation and heading angle degree.

关键词： visual localization semantic map bird-eye-view transformer pose estimation

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he BCM1-EGY1 module balances chlorophyll biosynthesis and breakdown to confer chlorophyll homeostasis in land plants

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Molecular Plant 2025年第1期18卷 76-94页

作者： Dali Fu Hanlin zhou Bernhard Grimm peng Wang School of Biological Sciences The University of Hong KongHong Kong SAR 999077China Institute of Biology/Plant Physiology Humboldt-Universität zu BerlinPhilippstrasse13Building 1210115 BerlinGermany State Key Laboratory of Agrobiotechnology The Chinese University of Hong KongHong Kong SAR 999077China

Chlorophyll metabolism has evolved during plant *** strictly light-dependent nature of chlorophyll biosynthesis found in angiosperms requires tight coordination of chlorophyll biosynthesis and breakdown to achieve chlorophyll ***,the specific control mechanisms remain largely ***,we demonstrate that the scaffold protein BALANCE OF CHLOROPHYLL METABOLISM1(BCM1)has co-evolved with the carboxy-terminal domains of specific enzymes involved in chlorophyll biosynthesis and breakdown,including GENOMES UNCOUPLED 4(GUN4)and Mg-dechelatase 1(SGR1).We found that the land plant-specific interaction of BCM1 with the carboxy-terminal domains of GUN4 and SGR1 is indispensable for concurrent stimulation of chlorophyll biosynthesis and suppression of chlorophyll *** land plant-specific carboxy-terminal domain is essential for the membrane docking and turnover of GUN4,whereas it is key for proteolysis of *** importantly,we identified the metallopeptidase Gravitropism-deficient and Yellow-green 1(EGY1)as the proteolytic machinery responsible for BCM1-mediated proteolysis of *** summary,this study reveals the BCM1-EGY1 module has evolved to maintain chlorophyll homeostasis by the post-translational control of the balance between chlorophyll biosynthesis and *** mechanism thus represents an evolutionary response to the metabolic demands imposed on plants in terrestrial environments.

关键词： chlorophyll homeostasis scaffold protein BCM1 proteolytic machinery EGY1 post-translational control

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