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基于光泵效应诱导涡旋光的通断控制实验教学设计

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大学物理实验 2024年第3期37卷 45-49页

作者：王志平陈俊飞吴伟吕亮胡志家安徽大学物理与光电工程学院安徽合肥230601

随着对涡旋光研究的深入,对涡旋光在各种介质中的传输控制提出了更高的要求。本实验利用光泵效应在三能级热源子系统中完成了对涡旋光传输通断的控制,通过分别控制信号光的失谐程度、泵浦光的光功率大小以及铷原子气体池的温度高低等参... 详细信息

随着对涡旋光研究的深入,对涡旋光在各种介质中的传输控制提出了更高的要求。本实验利用光泵效应在三能级热源子系统中完成了对涡旋光传输通断的控制,通过分别控制信号光的失谐程度、泵浦光的光功率大小以及铷原子气体池的温度高低等参数来调控信号光的传输透过率,从而实现对涡旋光传输的通断控制。本文将理论与实验相结合,使学生通过实验更加充分地理解理论知识,培养和提高了学生的实践能力和创新意识。

关键词：涡旋光光泵效应科研能力光场控制

Improved Reall-Santos method for AdS black holes in general 4-derivative gravities

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 74-86页

作者： Peng-Ju Hu liang Ma Hong lü Yi Pang Center for Joint Quantum Studies and Department of Physics School of ScienceTianjin UniversityTianjin 300350China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou 350207China Peng Huanwu Center for Fundamental Theory Hefei 230026China

For asymptotically flat black holes,Reall-Santos method is a convenient tool to compute leading higher derivative corrections to the thermodynamic quantities without actually solving the modified field ***,there are subtleties in its generalization to asymptotically AdS black holes with general higher derivative *** of all,it is necessary to know all the higher derivative holographic counterterms and the surface terms implementing the variational principle and subtracting the *** then needs to solve for the modified AdS radius and rescale the time coordinate in an appropriate way such that the induced metric on the conformal boundary of AdS black hole is not *** observe that Reall-Santos method can be directly applied to a particular 4-derivative gravity model,known as the Einstein-Weyl gravity,which does not modify the AdS radius and requires only the Gibbons-Hawking-York term and holographic counterterms for the 2-derivative *** thus suggest that to compute the thermodynamic quantities of AdS black holes in general 4-derivative theories of gravity,one simply needs to transform it to a Einstein-Weyl gravity with identical thermodynamic variables by appropriate field *** explicitly verify this proposal with spherically-symmetric and static charged black holes in Einstein-Maxwell theory extended with generic 4-derivative interactions.

关键词： black holes thermodynamics higher-derivative corrections effective theories higher dimensional black holes quantum gravity

Neutrino luminosity of stars with different masses

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Research in Astronomy and Astrophysics 2020年第1期20卷 35-42页

作者： Yang Shi Xun Xue Chun-Hua Zhu Zhao-Jun Wang He-lei liu lin li Guo-liang lü School of Physics and Technology Xinjiang UniversityUrumqi 830046China Department of Physics East China Normal UniversityShanghai 2000062China

Neutrinos play an important role in stellar *** are produced by nuclear reactions or thermal *** the stellar evolution code Modules for Experiments in Stellar Astrophysics(MESA),we study stellar neutrino luminosity with different *** neutrino luminosities of stars with different initial masses at different evolutionary stages are *** find that the neutrino flux of a star with 1 M⊙ mass at an evolutionary age of 4.61×10^9 yr is consistent with that of the *** general,neutrinos are produced by nuclear reactions,and the neutrino luminosity of stars is about one or two magnitudes lower than the photo ***,neutrino luminosity can exceed photo luminosity during the helium flash which can occur for stars with a mass lower than 8 M⊙.Although the helium flash does not produce neutrinos,plasma decay,one of the thermal processes,can efficiently make neutrinos during this *** to the high mass-loss rate,a star with a mass of 9 M⊙ does not undergo the helium *** neutrinos mainly originate from nuclear reactions until the end of the AGB *** the end of the AGB stage,its neutrino luminosity results from plasma decay which is triggered by the gravitational energy release because of the stellar core contracting.

关键词： stars:evolution stars:fundamental parameters nuclear reactions nucleosynthesis abundances

Overexpression of N-cadherin is correlated with metastasis and worse survival in colorectal cancer patients

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Chinese Science Bulletin 2013年第28期58卷 3529-3534页

作者： ZHUO HongQing JIANG KeWei DONG lingYi ZHU Yi lü liang lü You ZHANG YanBin ZHANG Hui YE YingJiang WANG Shan Department of Gastrointestinall Surgery Laboratory of Surgical OncologyPeking University People's Hospital Peking University

N-cadherin is related to the progression and metastases of several solid ***,it was still unclear whether N-cadherin is overexpressed in colorectal malignant tumors that have stronger malignant *** this study,we used immunohistochemistry to detect the expression patterns of N-cadherin in both the primary tumors and their normal mucosa tissues of 120patients with colorectal *** revealed that N-cadherin was expressed in 78.3%(94/120)of colorectal tumor tissues and in only 9.2%(11/120)of paired distant normal mucosa tissues with a significant difference(P=0.000).The low,moderate,and high expression of N-cadherin protein was 42.5%,30.8%,and 26.7%,respectively.N-cadherin overexpression was associated with advanced TNM stage,lymph nodes metastasis and distant metastasis(Plower overall survival rate than those with moderate and low expression,and patients with low expression had a better survival rate than those with moderate and high expression(Plusion,high N-cadherin expression may lead to tumor aggressiveness and metastatic potential in colorectal cancer,and may prove to be a possible prognostic factor.

关键词：大肠癌患者恶化恶性肿瘤过度表达免疫组化法表达模式肿瘤组织

A study of type I X-ray bursts from an NS accreting pure helium

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Research in Astronomy and Astrophysics 2020年第4期20卷 44-48页

作者： Yan-Cun Ma He-lei liu Chun-Hua Zhu Zhao-Jun Wang lin li Guo-liang lü School of Physics and Technology Xinjiang UniversityUrumqi 830046China

Using the Modules for Experiments in Stellar Astrophysics(MESA) code, we investigate Type I X-ray bursts(XRBs) produced by neutron stars(NSs) accreting pure helium, which are called intermediate XRBs in observations. We simulate 21 models for intermediate XRBs with various mass-accretion rates(M) from 2.5 × 10^-8 to 5 × 10^-10 M⊙yr^-1. Compared with normal XRBs, in which the NS accretes matter with solar metallicity, intermediate XRBs have higher luminosity and longer recurrence time,which are essentially consistent with observations. We find that the recurrence time of intermediate XRBs is proportional to M^-2.0.

关键词： stars:accretion star:neutron stars

Direct amination of benzene to aniline with several typical vanadium complexes

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Chinese Chemical letters 2009年第2期20卷 238-240页

作者： Yu Fen lü liang Fang Zhu Qiu Yuan liu Bin Guo Xiao Ke Hu Chang Wei Hu Key laboratory of Green Chemistry and Technology (Sichuan University) Ministry of Education College of Chemistry Sichuan University Chengdu 610064 PR China

The liquid-phase direct catalytic amination of benzene to aniline was performed in acetic acid water solvent using a series of vanadium （Ⅲ, Ⅳ,Ⅴ） complexes with N,O- or O,O-ligands as catalysts and hydroxylamine hydrochloride as the aminating agent. The vanadium complexes exhibited much higher selectivity towards the production of aniline than NaVO3 or VOSO4. Under the optimized conditions, an aniline yield of 42.5% and a TON of 48 with a high selectivity of above 99.9% was obtained using 0.2 mmol of [VO（OAc）2] as the catalyst.

关键词： Amination Benzene Hydroxylamine Vanadium complexes

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 ***,a distributed dynamic ETM which only uses local information is developed for the MASs with large-scale *** 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 *** addition,it is easier to find a trade-off between the convergence rate and the minimum inter-event time by an adjustable ***,the results are extended to regional consensus of the MASs with the bounded control *** 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

Heavy element contributions of rotating massive stars to interstellar medium

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Research in Astronomy and Astrophysics 2021年第5期21卷 287-295页

作者： Rui-Qing Wu Chun-Hua Zhu Guo-liang lv Zhao-Jun Wang He-lei liu School of Physical Science and Technology Xinjiang UniversityUrumqi 830046China

Employing the stellar evolution code Modules for Experiments in Stellar Astrophysics(MESA),we calculate yields of heavy elements from massive stars via stellar wind and core−collapse supernova(CCSN)ejecta to the interstellar medium(ISM).In our models,the initial masses(Mini)of massive stars are taken from 13 to 80 M⊙,their initial rotational velocities(V)are 0,300 and 500 km s^(−1),and their metallicities are[Fe/H]=−3,−2,−1 and *** yields of heavy elements coming from stellar winds are mainly affected by stellar rotation which changes the chemical abundances of stellar surfaces via chemically homogeneous evolution,and enhances mass-loss *** estimate that the stellar wind can produce heavy element yields of about 10^(−2)(for low metallicity models)to a mass of severalM⊙(for low metallicity and rapid rotation models).The yields of heavy elements produced by CCSN ejecta also depend on the large amount of remnantmass which is mainly determined by the mass of the *** models calculate that the yields of heavy elements produced by CCSN ejecta can get up to several M⊙.Compared with stellar wind,CCSN ejecta has a greater contribution to the heavy elements in *** also compare the 56Ni yields calculated in this work with the observational *** models only explain the 56Ni masses produced by faint SNe or normal SNe with progenitor mass lower than about 25 M⊙,and greatly underestimate the 56Ni masses produced by stars with masses higher than about 30M⊙.

关键词： Stars:massive rotation ISM:abundances

Machine learning the nuclear mass

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Nuclear Science and Techniques 2021年第10期32卷 88-100页

作者： Ze-Peng Gao Yong-Jia Wang Hong-liang lu Qing-Feng li Cai-Wan Shen ling liu College of Physics Science and Technology Shenyang Normal UniversityShenyang 110034China School of Science Huzhou UniversityHuzhou 313000China HiSilicon Research Department Huawei Technologies Co.Ltd.Shenzhen 518000China Institute of Modern Physics Chinese Academy of ScienceLanzhou 730000China

Background:The masses of-2500 nuclei have been measured experimentally;however,>7000 isotopes are predicted to exist in the nuclear landscape from H(Z=1)to Og(Z=118)based on various theoretical *** the mass of the remaining isotopes is a popular topic in nuclear *** learning has served as a powerful tool for learning complex representations of big data in many ***:We use light Gradient Boosting Machine(lightGBM),which is a highly efficient machine learning algorithm,to predict the masses of unknown nuclei and to explore the nuclear landscape on the neutron-rich side from learning the measured nuclear ***:Several characteristic quantities(e.g.,mass number and proton number)are fed into the lightGBM algorithm to mimic the patterns of the residual δ(Z,A)between the experimental binding energy and the theoret-ical one given by the liquid-drop model(lDM),Duflo–Zucker(DZ,also dubbed DZ28)mass model,finite-range droplet model(FRDM,also dubbed FRDM2012),as well as the Weizsacker–Skyrme(WS4)model to refine these mass ***:By using the experimental data of 80%of known nuclei as the training dataset,the root mean square devia-tions(RMSDs)between the predicted and the experimental binding energy of the remaining 20%are approximately 0.234±0.022,0.213±0.018,0.170±0.011,and 0.222±0.016 MeV for the lightGBM-refined lDM,DZ model,WS4 model,and FRDM,*** values are approximately 90%,65%,40%,and 60%smaller than those of the corresponding origin mass *** RMSD for 66 newly measured nuclei that appeared in AME2020 was also significantly *** one-neutron and two-neutron separation energies predicted by these refined models are consistent with several theoretical predictions based on various physical *** addition,the two-neutron separation energies of several newly measured nuclei(e.g.,some isotopes of Ca,Ti,Pm,and Sm)pre-dicted with lightGBM-refined mass models are also in good agreement with

关键词： Nuclear mass Machine learning Binding energy Separation energy