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Laser frequency offset-locking using electromagnetically induced transparency spectroscopy of (85)Rb in magnetic field

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Chinese Physics B 2018年第9期27卷 296-300页

作者： Han-Mu Wang Hong Cheng Shan-Shan Zhang pei-pei xin Zi-Shan Xu Hong-Ping Liu State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 China University of Chinese Academy of Sciences Beijing 100049 China

We have experimentally offset-locked the frequencies of two lasers using electromagnetically induced transparency（EIT） spectroscopy of ^（85）Rb vapor with a buffer gas in a magnetic field at room temperature. The magnetic field is generated by a permanent magnet mounted on a translation stage and its field magnitude can be varied by adjusting the distance between the magnet and Rb cell, which maps the laser locking frequency to the space position of the magnet. This frequency-space mapping technique provides an unambiguous daily laser frequency detuning operation with high accuracy.A repeatability of less than 0.5 MHz is achieved with the locking frequency detuned up to 184 MHz when the magnetic field varies from 0 up to 80 G.

关键词： electromagnetically induced transparency offset-lock rubidium atom magnetic field

Mechanism of action of Linggui Zhugan Decoction in treating non-alcoholic fatty liver disease using untargeted metabolomics approach

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Traditional Medicine Research 2025年第2期10卷 65-76页

作者： Huan pei Ren-Lin Li xin-Ran Song Qian-Qian Wan Yu-Ming Wang Han-Zhou Li Wei-Quan Xu Jia-Bao Liao Wei-Bo Wen Jing Miao Huan-Tian Cui School of Basic Medicine Yunnan University of Chinese MedicineKunming 650599China School Clinical Medical College Yunnan University of Chinese MedicineKunming 650599China First School of Clinical Medicine Yunnan University of Chinese MedicineKunming 650599China School of Integrative Chinese and Western Medicine Tianjin University of Traditional Chinese MedicineTianjin 301617China Department of Pharmacy Tianjin Second People's HospitalTianjin 300192China

Background:Non-alcoholic fatty liver disease(NAFLD)is a liver disorder characterized by the accumulation and degeneration of fat in the liver cells,a condition that may further deteriorate and lead to cirrhosis and liver *** studies showed that metabolic dysfunction can promote NAFLD *** Zhugan Decoction(LGZGD)has therapeutic effects on *** mechanism of LGZGD still remains *** study was to examine the impact of LGZGD on the metabolic processes involved in the development of ***:A mice model of NAFLD was treated with *** therapeutic potential of LGZGD was evaluated by assessing the activity of transaminases,lipids levels of blood,and pathological changes in the liver of the mice model of ***,this study also evaluated the influence of LGZGD on liver inflammation and oxidative ***:The results of untargeted metabolomics analysis showed that LGZGD reduced the disordered lipid metabolism in NAFLD *** improved the oxidative stress and also reduced the levels of pro-inflammatory cytokines in the *** metabolomics analysis of liver samples revealed that LGZGD treatment improved metabolic disorders,including alanine,aspartate,glutamate,glycerophospholipid metabolism,and citrate *** RT-qPCR and Western blot results showed that LGZGD could regulate the expression of key enzymes in the metabolic pathway of the citrate cycle,including ATP-citrate lyase(ACLY),alanine-glyoxylate aminotransferase-2(AGXT2),phosphatidylethanolamine N-methyltransferase(PEMT),and succinate dehydrogenase(SDH).Conclusion:We found that LGZGD can treat NAFLD by reducing inflammatory responses,inhibiting oxidative stress,regulating alanine,aspartate,glutamate,and glycerophospholipid metabolism,and citrate cycle pathways.

关键词： NAFLD LGZGD untargeted metabolomics glycerophospholipid metabolism citrate cycle

Lower Bound for Quantum Integration Error on Anisotropic Sobolev Classes

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Acta Mathematica Sinica,English Series 2010年第4期26卷 669-678页

作者： pei xin YE School of Mathematical Sciences and LPMC Nankai University Tianjin 300071 P. R. China

We study the approximation of the integration of multivariate functions in the quantum model of computation. Using a new reduction approach we obtain a lower bound of the n-th minimal query error on anisotropic Sobolev class R（Wpr（[0, 1]d））（r R＋d）. Then combining this result with our previous one we determine the optimal bound of n-th minimal query error for anisotropic Hblder- Nikolskii class R（H∞r（[0,1]d）） and Sobolev class R（W∞r（[0,1]d））. The results show that for these two types of classes the quantum algorithms give significant speed up over classical deterministic and randomized algorithms.

关键词： quantum integration anisotropic Sobolev classes Holder-Nikolskii classes n-th minimal query error

Analytical Method for the Wave Diffraction of Asymmetrically Arranged Breakwaters

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China Ocean Engineering 2024年第5期38卷 797-808页

作者： ZHOU pei-xin ZHANG Hong-sheng College of Ocean Science and Engineering Shanghai Maritime UniversityShanghai 201306China Bureau of Transport of Beilun District of Ningbo Zhejiang 315800China

The layout forms of several breakwater structures can be generalized as asymmetrical arrangements in actual ***,the problem of wave diffraction around asymmetrically arranged breakwaters has not been adequately *** this study,we propose an analytical method of wave diffraction for regular waves passing through asymmetrically arranged breakwaters,and we use the Nyström method to obtain the analytical solution *** compared the results of this method with those of previous analytical solutions and with numerical results to demonstrate the validity of our *** also provided diffraction coefficient diagrams of breakwaters with different layout ***,we described the analytical expression for the problem of diffraction through long-wave incident breakwaters and presented an analysis of the relationship between the diffraction coefficients and the widths of breakwater *** analytical method presented in this study contributes to the limited literature on the theory of wave diffraction through asymmetrically arranged breakwaters.

关键词： regular waves breakwaters analytical method wave diffraction

Long-term Evolution of Solar Activity and Prediction of the Following Solar Cycles

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Research in Astronomy and Astrophysics 2024年第3期24卷 194-204页

作者： pei-xin Luo Bao-Lin Tan National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

Solar activities have a great impact on modern high-tech systems,such as human aerospace activities,satellite communication and navigation,deep space exploration,and related scientific ***,studying the long-term evolution trend of solar activity and accurately predicting the future solar cycles are highly *** on the wavelet transform and empirical function fitting of the longest recorded data of the annual average relative sunspot number(ASN)series of 323 yr to date,this work decisively verifies the existence of the solar century cycles and confirms that its length is about 104.0 yr,and the magnitude has a slightly increasing trend on the timescale of several hundred *** on this long-term evolutionary trend,we predict solar cycles 25 and26 by using phase similar prediction *** for solar cycle 25,its maximum ASN will be about146.7±33.40,obviously stronger than solar cycle *** peak year will occur approximately in 2024,and the period will be about 11±1 *** for solar cycle 26,it will start around 2030,and reach its maximum between2035 and 2036,with maximum ASN of about 133.0±3.200,and period of about 10 yr.

关键词： Sun activity-Sun evolution-(Sun) sunspots-methods data analysis

Wear law in mixed lubrication based on stress-promoted thermal activation

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Friction 2021年第4期9卷 710-722页

作者： xin pei Wei PU Jialong YANG Ying ZHANG School of Aeronautics and Astronautics Sichuan UniversityChengdu 610065China School of Manufacturing Science and Engineering Sichuan UniversityChengdu 610065China

Although several empirical wear formulas have been proposed,theoretical approaches for predicting surface topography evolution during sliding wear are *** this study,we propose a novel wear-prediction method,wherein the energy-based Arrhenius equation is combined with a mixed elastohydrodynamic lubrication(EHL)model to predict the point-contact wear process in mixed *** surface flash temperature and contact pressure are considered in the wear *** results are compared with the experimental results to verify the *** surface topography evolutions are observed during the wear *** influences of load and speed on wear are *** simulation results based on the Arrhenius equation relationship shows good agreement with the results of experiments as well as the Archard wear ***,the Arrhenius equation is more accurate than the Archard wear theory in some aspects,such as under high-temperature *** results indicate that combining the wear formulas with the mixed EHL simulation models is an effective method to study the wear behavior over time.

关键词： mixed lubrication sliding wear Archard Arrhenius surface topography

Contact stiffness and damping of spiral bevel gears under transient mixed lubrication conditions

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Friction 2022年第4期10卷 545-559页

作者： Zongzheng WANG Wei PU xin pei Wei CAO School of Aeronautics and Astronautics Sichuan UniversityChengdu 610065China School of Construction Machinery Chang'an UniversityXi'an 710064China

Existing studies primarily focus on stiffness and damping under full-film lubrication or dry contact ***,most lubricated transmission components operate in the mixed lubrication region,indicating that both the asperity contact and film lubrication exist on the rubbing ***,a novel method is proposed to evaluate the time-varying contact stiffness and damping of spiral bevel gears under transient mixed lubrication *** method is sufficiently robust for addressing any mixed lubrication state regardless of the severity of the asperity *** on this method,the transient mixed contact stiffness and damping of spiral bevel gears are investigated *** results show a significant difference between the transient mixed contact stiffness and damping and the results from Hertz(dry)*** addition,the roughness significantly changes the contact stiffness and damping,indicating the importance of film lubrication and asperity *** transient mixed contact stiffness and damping change significantly along the meshing path from an engaging-in to an engaging-out point,and both of them are affected by the applied torque and rotational *** addition,the middle contact path is recommended because of its comprehensive high stiffness and damping,which maintained the stability of spiral bevel gear transmission.

关键词： mixed contact stiffness and damping transient mixed lubrication real machined roughness different contact trajectories spiral bevel gears

BDS B1I multipath channel statistical model comparison between static and dynamic scenarios in dense urban canyon environment

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Satellite Navigation 2020年第1期1卷 287-302页

作者： xin Chen Di He Ling pei Shanghai Key Laboratory of Navigation and Location-based Service School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityDongchuan Road 800Shanghai 200240China

Global Navigation Satellite System(GNSS)multipath channel models are fundamental and critical for signal simulation and receiver performance *** also aid the designing of suitable multipath error mitigation algorithms when the properties of multipath channel are ***,there is insufficient existing research on BeiDou Navigation Satellite System(BDS)signal multipath channel *** this study,multipath channel statistical models are established on the basis of extensive datasets of the BDS B1I signal.A multipath parameter estimation algorithm is designed to extract information of multipath rays from the intermediate frequency *** delay,power loss,Doppler fading frequency,and lifetime distribution models for static and dynamic vehicle platforms are established and compared,and the effects of the satellite orbit type and platform speed on the models are *** results reveal the detailed distribution and variation characteristics of the multipath parameters and are valuable for the development of accurate urban navigation systems.

关键词： Multipath channel statistical model Multipath delay Multipath power loss Multipath Doppler fading frequency Multipath lifetime

Truncation and aliasing errors for Whittaker-Kotelnikov-Shannon sampling expansion

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Applied Mathematics(A Journal of Chinese Universities) 2012年第4期27卷 412-418页

作者： YE pei-xin SONG Zhan-jie School of Mathematics and LPMC Nankai UniversityTianjin 300071China Department of Mathematics School of ScienceTianjin UniversityTianjin 300072China

Let B^pΩ, 1 ≤ p 〈 ∞, be the space of all bounded functions from Lp（R） which can be extended to entire functions of exponential type Ω. The uniform error bounds for truncated Whittaker-Kotelnikov-Shannon series based on local sampling are derived for functions f ∈ B^pΩ without decay assumption at infinity. Then the optimal bounds of the aliasing error and truncation error of Whittaker-Kotelnikov-Shannon expansion for non-bandlimited functions from Sobolev classes L/（Wp（R）） are determined up to a logarithmic factor.

关键词： Whittaker-Kotelnikov-Shannon theorem localized sampling truncation error aliasing error,Sobolev class.