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Effects of Field-Correlation on Raman-Enhanced Nondegenerate Four-Wave Mixing Spectra

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Chinese Physics Letters 1997年第4期14卷 277-280页

作者： MI Xin yu zu-he JIANG Qian LI Xiao-feng FU Pan-ming Laboratory of Optical Physics Institute of Physics&Center for Condensed MatterChinese Academy of SciencesBeijing 100080

The effects of field correlation on Raman-enhanced nondegenerate four-wave mixing(REN-FWM)have been investigated by examining the RENFWM spectra as a function of time delay between two *** enhancement of the ratio between the resonant and nonresonant REN-FWM signal intensities was found as the time delay was increased when the laser had broadband linewidth.

关键词： delay degenerate resonant

Ultrafast Modulation Spectroscopy in Four-Level System

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Chinese Physics Letters 1998年第6期15卷 420-422页

作者： yu zu-he MI Xin JIANG Qian LI Xiao-feng FU Pan-ming Laboratory of Optical Physics Institute of Physics&Center for Condensed Matter PhysicsChinese Academy of SciencesBeijing 100080

Based on the interference between two two-photon processes,we reported a four-level ultrafast modulation spectroscopy in Na vapor,where 3S,3P,5S,and 4D formed a four-level *** studied the temporal behavior of the four-wave mixing signal intensity and obtained signal modulation with period 25fs,corresponding to the splitting between 5s and *** technique can achieve Doppler-free precision in the measurement of the energy level splitting between two excited states which are dipolar forbidden from the ground state.

关键词： state splitting excited

Observation of Rydberg Series in Sodium Vapour by Two-Photon Resonant Nondegenerate Four-Wave Mixing

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Chinese Physics Letters 2001年第9期18卷 1202-1204页

作者： WANG Yan-Bang JIANG Qian LI Long MI Xin yu zu-he FU Pan-Ming Laboratory of Optical Physics Institute of Physics and Center for Condensed Matter PhysicsChinese Academy of SciencesBeijing 100080

We apply two-photon resonant nondegenerate four-wave mixing with a resonant intermediate state for the obser- vation of Rydberg states in sodium vapour. The broadening and shift of the sodium 3S- 11D transition perturbed by argon are investigated. This technique can achieve Doppler-free resolution of narrow spectral structures of Rydberg levels if lasers with narrow bandwidths are employed.

关键词： Rydberg degenerate resonant

Phase-Sensitive Detection of Raman-Enhanced Nondegenerate Four-Wave Mixing by Polarization Interference

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Chinese Physics Letters 2001年第1期18卷 54-56页

作者： JIANG Qian MI Xin yu zu-he WANG Yan-Bang WANG Li-Jun FU Pan-Ming Laboratory of Optical Physics Institute of Physics&Center for Condensed Matter Physics Chinese Academy of SciencesBeijing 100080

We demonstrated a phase-sensitive method for studying the Raman-enhanced nondegenerate four-wave mixing(RENFWM).The reference beam is another four-wave mixing signal,which propagates along the same optical path as the RENFWM *** method is used for studying the phase dispersion of the third-ordersusceptibility X^((3))and for the optical heterodyne detection of the RENFWM signal.

关键词： optical FWM mixing

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30年来的中国近代思想文化史研究

安徽史学 2009年第1期 112-124,59页

作者：左玉河中国社会科学院近代史所北京100006

30年来的中国近代思想史研究,依据研究重心的变化可以分为三个阶段:一是1978年到80年代末,研究重点集中于思想家个案及政治思想史方面;二是80年代末到90年代末,研究重心逐渐转变为以社会思潮史及思想家个案为主;三是90年代末以来,研究... 详细信息

30年来的中国近代思想史研究,依据研究重心的变化可以分为三个阶段:一是1978年到80年代末,研究重点集中于思想家个案及政治思想史方面;二是80年代末到90年代末,研究重心逐渐转变为以社会思潮史及思想家个案为主;三是90年代末以来,研究重心集中于社会思潮史和学术思想史领域。正是在研究重心的逐渐转移过程之中,近代思想史研究的广度不断拓宽,研究深度亦渐次深化。改革开放之后中国学术界最引人注目的现象之一,是中国文化史研究的复兴;90年代以后中国文化史发展的新趋势,是社会文化史研究的勃然兴起。长期无人问津或受人冷落的研究领域,如近代科技文化、民间宗教、民间意识与观念、文化心态、公共空间领域、新词语与观念变迁等,受到学术界的广泛关注并出现了许多研究成果。近代社会文化史正在成为史学新观念和新方法的一个重要生长点。

关键词：中国近代思想史近代文化史社会文化史

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Precision storage lifetime measurements of highly charged heavy ions in the CSRe storage ring using a Schottky resonator

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Nuclear Science and Techniques 2025年第1期36卷 150-160页

作者： Qian Wang Xin-Liang Yan Guang-yu Zhu Shahab Sanjari Li-Jun Mao he Zhao yuri ALitvinov Rui-Jiu Chen Meng Wang yu-Hu Zhang You-Jin yuan Jun-Xia Wu Hong-Yang Jiao yue yu zu-Yi Chen Yin-Fang Luo Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China GSI helmholtzzentrum für Schwerionenforschung Planckstrasse 164291 DarmstadtGermany FH Aachen University of Applied Sciences Heinrich-Mussmann-Str.152428 JülichGermany

Schottky mass spectrometry utilizing heavy-ion storage rings is a powerful technique for the precise mass and decay half-life measurements of highly charged *** to the nondestructive ion detection features of Schottky noise detectors,the number of stored ions in the ring is determined by the peak area in the measured revolution frequency *** of their intrinsic amplitude-frequency characteristic(AFC),Schottky detector systems exhibit varying sensitivities at different *** low-energy electron-cooled stored ions,a new method is developed to calibrate the AFC curve of the Schottky detector system of the Experimental Cooler Storage Ring(CSRe)storage ring located in Lanzhou,*** the amplitude-calibrated frequency spectrum,a notable refinement was observed in the precision of both the peak position and peak *** a result,the storage lifetimes of the electron-cooled fully ionized^(56)Fe^(26+)ions were determined with high precision at beam energies of 13.7 and 116.4 MeV/u,despite of frequency drifts during the *** electron cooling was turned off,the effective vacuum condition experienced by the 116.4 MeV/u^(56)Fe^(26+)ions was determined using amplitude-calibrated spectra,revealing a value of 2×10^(−10)mbar,which is consistent with vacuum gauge readings along the CSRe *** method reported herein will be adapted for the next-generation storage ring of the HIAF facility under construction in Huizhou,*** can also be adapted to other storage ring facilities worldwide to improve precision and enhance lifetime measurements using many ions in the ring.

关键词： Lifetime measurement Schottky mass spectrometry Sensitivity response Highly charged heavy ion Resonator UH vacuum Nondestructive diagnostics

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Stability and Stabilization of Sampled-Data Based LFC for Power Systems:A Data-Driven Method

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IEEE/CAA Journal of Automatica Sinica 2025年第1期12卷 291-293页

作者： yu-Long Fan Chuan-Ke Zhang Yong he the School of Automation China University of Geosciences the Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems the Engineering Research Center of Intelligent Technology for Geo-Exploration Ministry of Education IEEE

Dear Editor,This letter is concerned with stability analysis and stabilization design for sampled-data based load frequency control(LFC) systems via a data-driven method. By describing the dynamic behavior of LFC systems based on a data-based representation, a stability criterion is derived to obtain the admissible maximum sampling interval(MSI) for a given controller and a design condition of the PI-type controller is further developed to meet the required MSI. Finally, the effectiveness of the proposed methods is verified by a case study.

关键词： Sampled data control systems

Metagenomic perspectives on antibiotic resistance genes in tap water:The environmental characteristic,potential mobility and health threat

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Journal of Environmental Sciences 2025年第1期147卷 582-596页

作者： Qiyue Meng Yibo Zhang Da he yu Xia Jie Fu Chenyuan Dang School of Environmental Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China Key Laboratory of Ecological Impacts of Hydraulic Projects and Restoration of Aquatic Ecosystem of Ministry of Water Resources Institute of HydroecologyMinistry of Water Resources&Chinese Academy of SciencesWuhan 430074China School of Environmental Science and Engineering College of EngineeringSouthern University of Science and TechnologyShenzhen 518055China

As an emerging environmental contaminant,antibiotic resistance genes(ARGs)in tap water have attracted great *** studies have provided ARG profiles in tap water,research on their abundance levels,composition characteristics,and potential threat is still ***,9 household tap water samples were collected from the Guangdong-Hong Kong-Macao Greater Bay Area(GBA)in ***,75 sets of environmental sample data(9 types)were downloaded from the public *** was then performed to explore the differences in the abundance and composition of ARGs.221 ARG subtypes consisting of 17 types were detected in tap *** the ARG abundance in tap water was not significantly different from that found in drinking water plants and reservoirs,their composition *** tap water samples,the three most abundant classes of resistance genes were multidrug,fosfomycin and MLS(macrolide-lincosamidestreptogramin)ARGs,and their corresponding subtypes ompR,fosX and macB were also the most abundant ARG *** the potential mobility,vanS had the highest abundance on plasmids and viruses,but the absence of key genes rendered resistance to vancomycin ***,the majority of ARGs present in tap water were those that have not been assessed and are currently not listed as high-threat level ARG families based on the World health Organization *** the current potential threat to human health posed by ARGs in tap water is limited,with persistent transfer and accumulation,especially in pathogens,the potential danger to human health posed by ARGs should not be ignored.

关键词： Antibiotic resistance genes Tap water Plasmids Viruses health threat

Stability switches mechanism and PID control in reaction-diffusion network-organized neural systems with transmission delays

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Science China(Technological Sciences) 2025年第2期68卷 199-215页

作者： Xiangyu DU Min XIAO Wenwu yu Jiajin he College of Automation&College of Artificial Intelligence Nanjing University of Posts and TelecommunicationsNanjing 210023China College of Mathematics Southeast UniversityNanjing 211189China

Traditionally,the spatiotemporal dynamics of neural networks have been analyzed in the locally continuous *** this modeling approach is straightforward and practical,it fails to encapsulate real-world networks’intricate topological structures and ***,the mechanisms of stability switches induced by time delays and diffusion effects in networkorganized systems are still ***,effective dynamic optimization strategies for network-organized models remain to be *** this study,we develop a delayed reaction-diffusion neural network model on complex *** system incorporates the effects of inter-nodal diffusion coupling and exhibits profound architectural *** then pioneer the proportional-integral-derivative(PID)feedback control into the network-organized model to modulate dynamic *** linear stability analysis is conducted firstly,demonstrating that Turing patterns and Hopf bifurcation can be induced in the controlled neural network by varying diffusion coefficients and time ***,the bifurcation direction is deduced via the center manifold ***,a series of simulations are performed to validate the theoretical analysis and substantiate the efficacy of the PID control *** results exhibit that the PID feedback controller can flexibly regulate the dynamics of the network-organized systems and possesses excellent disturbance rejection capabilities.

关键词： complex network neural networks PID control turing instability hopf bifurcation time delays turing pattern

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