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Electric Character of Strange Stars

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Chinese Physics Letters 1999年第10期16卷 778-780页

作者： xu ren-xin QIAO Guo-jun National Astronomical Observatories Beijing Astronomical ObservatoryChinese Academy of ScienceBeijing 100012 CAS-PKU Joint Beijing Astrophysical Center and Department of Astronomy Peking UniversityBeijing 100871

Using the Thomas-Fermi model,we investigated the electric characteristics of a static non-magnetized strange star without *** exact solutions of electron number density and electric field above the quark surface are *... 详细信息

关键词： quark concerned exact

Bare Strange Stars Might Not Be Bare

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Chinese Physics Letters 1998年第12期15卷 934-936页

作者： xu ren-xin QIAO Guo-jun Department of Geophysics Peking UniversityBeijing 100871 Chinese Academy of Sciences-Peking University Joint Beijing Astrophysical Center Beijing 100871

It is proposed that the bare strange matter stars might not be bare,and the observed pulsars might be in fact the bare strange *** intensely magnetized strange matter stars rotate,the induced unipolar electric fields would be large enough to construct *** situation is very similar to that discussed by many authors for rotating neutron ***,the strange stars with accretion crusts in binaries could act as x-ray pulsars or x-ray *** are some advantages if pulsars are bare strange stars.

关键词： stars crust accretion

Differentiating Neutron Star Models by X-Ray Polarimetry

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Chinese Physics Letters 2013年第5期30卷 191-194页

作者： LU Ji-Guang xu ren-xin FENG Hua School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871 Department of Engineering Physics and Center for Astrophysics Tsinghua UniversityBeijing 100084

The nature of pulsars is still unknown because of the non-perturbative effects of the fundamental strong interaction,so various models of pulsar inner structures are suggested,either for conventional neutron stars or quark ***,a quark-cluster matter state is conjectured for cold matter at supranuclear density,and as a result pulsars can be quark-cluster *** understanding the different manifestations,the most important issue is to find an effective way to observationally differentiate these models.X-ray polarimetry plays an important role *** thermal x-ray polarization of quark/quark-cluster stars is focused on,and while the thermal x-ray linear polarization percentage is typically higher than~10%in normal neutron star models,the percentage of quark/quark-cluster stars is almost *** could then be an effective method to identify quark/quark-cluster stars by soft x-ray *** are therefore expecting to detect thermal x-ray polarization in the coming decades.

关键词： quark cluster thermal

Particle Emission-Dependent Timing Noise of Pulsars

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Chinese Physics Letters 2011年第1期28卷 230-232页

作者： LIU Xiong-Wei NA xue-Sen xu ren-xin QIAO Guo-Jun School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University Beijing 100871

Though pulsars spin regularly, the differences between the observed and predicted ToA （tune of arrival）, known as ＂timing noise＂, can still reach a few milliseconds or more. We try to understand the noise in this study. As proposed by xu and Qiao in 2001, both dipole radiation and particle emission would result in pulsar braking. Accordingly, possible fluctuation of particle current flow is suggested here to contribute significant ToA variation of pulsars. We find that the particle emission fluctuation could lead to timing noise which cannot be eliminated in timing process and that a longer period fluctuation would arouse a stronger noise. The simulated timing noise profile and amplitude are in agreement with the observed timing behaviors on the timescale of years.

关键词： Astrophysics and astroparticles

Coherent Inverse Compton Scattering Responsible for Pulsar Polarized and Unpolarized Emission

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Chinese Physics Letters 1999年第7期16卷 541-543页

作者： LIU Ji-feng QIAO Guo-jun xu ren-xin CAS-PKU Joint Beijing Astrophysics Center&Department of Geophysics Peking UniversityBeijing 100871 CCAST(World Laboratory) P.O.Box 8730Beijing 100080

A coherent inverse Compton scattering(ICS)mechanism is used to get polarization properties of radio emission of *** is found that particles moving along a ring with radius θ’=1/(√3γ)simultaneously contribute via coherent *** circular polarization can be easily gotten as well as linear polarization at the same *** theory releases the upper limit of Lorentz factor γ≤20 put by curvature radiation,and γ may take several thousands in ***,subpulse position angles do take diverse values,while mean position angle is associated with the projection of magnetic Geld *** it is natural to get commonly-seen S-shaped swing of mean position *** we present a simulation for position angle rotation,linear polarization,circular polarization of PSR1508+55,which means that the coherent ICS may be responsible for radio emission.

关键词： coherent circular polarized

聚合物电导率对0-3型压电复合材料极化性能的影响

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物理学报 2006年第8期55卷 4292-4297页

作者：徐任信陈文周静武汉理工大学材料科学与工程学院武汉430070

建立了0-3型压电复合材料的等效电学模型.分析了聚合物电导率对复合材料极化性能的影响,研究了聚苯胺改性03型锆钛酸铅聚偏氟乙烯复合材料极化性能与聚合物电导率之间的关系.理论分析和实验结果均表明,提高聚合物电导率可以提高复合材... 详细信息

建立了0-3型压电复合材料的等效电学模型.分析了聚合物电导率对复合材料极化性能的影响,研究了聚苯胺改性03型锆钛酸铅聚偏氟乙烯复合材料极化性能与聚合物电导率之间的关系.理论分析和实验结果均表明,提高聚合物电导率可以提高复合材料的极化性能.

关键词：压电复合材料电导率极化聚偏氟乙烯

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天文教育Ⅰ:万有引力与天体物理

天文学报 2021年第1期62卷 110-117页

作者：徐仁新北京大学物理学院天文学系北京100871 北京大学核物理与核技术国家重点实验室北京100871

分别从物理学和天文学角度引申出天体物理学科,特别关注万有引力在其中扮演的关键角色.无论在综合性大学亦或理工科院校,天文教育均有益于提高学生的科学和人文素养,而天体物理则是天文学的主要内涵.介绍了作者讲授"天体物理"课程的相... 详细信息

分别从物理学和天文学角度引申出天体物理学科,特别关注万有引力在其中扮演的关键角色.无论在综合性大学亦或理工科院校,天文教育均有益于提高学生的科学和人文素养,而天体物理则是天文学的主要内涵.介绍了作者讲授"天体物理"课程的相关信息以及个人认识.最后,以大气簇射μ子产生、啾质量、宇宙加速膨胀等教学案例结束,侧面诠释了作者的"天体物理"教育理念.

关键词：天文教育天体物理万有引力

Tailoring Light–Matter Interactions in Overcoupled Resonator for Biomolecule Recognition and Detection

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Nano-Micro Letters 2025年第1期17卷 262-280页

作者： Dongxiao Li Hong Zhou Zhihao ren Cheng xu Chengkuo Lee Department of Electrical and Computer Engineering National University of SingaporeSingapore 117583Singapore Center for Intelligent Sensors and MEMS(CISM) National University of SingaporeSingapore 117608Singapore

Plasmonic nanoantennas provide unique opportunities for precise control of light–matter coupling in surface-enhanced infrared absorption(SEIRA)spectroscopy,but most of the resonant systems realized so far suffer from the obstacles of low sensitivity,narrow bandwidth,and asymmetric Fano resonance ***,we demonstrated an overcoupled resonator with a high plasmon-molecule coupling coefficient(μ)(OC-Hμresonator)by precisely controlling the radiation loss channel,the resonator-oscillator coupling channel,and the frequency detuning *** observed a strong dependence of the sensing performance on the coupling state,and demonstrated that OC-Hμresonator has excellent sensing properties of ultra-sensitive(7.25%nm^(−1)),ultra-broadband(3–10μm),and immune asymmetric Fano *** characteristics represent a breakthrough in SEIRA technology and lay the foundation for specific recognition of biomolecules,trace detection,and protein secondary structure analysis using a single array(array size is 100×100μm^(2)).In addition,with the assistance of machine learning,mixture classification,concentration prediction and spectral reconstruction were achieved with the highest accuracy of 100%.Finally,we demonstrated the potential of OC-Hμresonator for SARS-CoV-2 *** findings will promote the wider application of SEIRA technology,while providing new ideas for other enhanced spectroscopy technologies,quantum photonics and studying light–matter interactions.

关键词： Plasmonic nanoantennas Light-matter interaction Surface-enhanced infrared absorption Overcoupled Biosensing

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钨球正撞击下低碳钢板的极限贯穿厚度研究

北京理工大学学报 2017年第6期37卷 551-556页

作者：徐豫新任杰王树山北京理工大学爆炸科学与技术国家重点试验室北京100081

研究低碳钢板在钨球正撞击下的极限贯穿厚度.采用6射弹弹道极限试验数据处理方法通过试验获得Φ6.0mm(93W)、Φ7.0mm(93W)、Φ6.0mm(95W)和Φ7.5mm(95W)共4种钨球对6种不同厚度Q235A钢板正撞击下的弹道极限速度和极限贯穿厚度范围.采用A... 详细信息

研究低碳钢板在钨球正撞击下的极限贯穿厚度.采用6射弹弹道极限试验数据处理方法通过试验获得Φ6.0mm(93W)、Φ7.0mm(93W)、Φ6.0mm(95W)和Φ7.5mm(95W)共4种钨球对6种不同厚度Q235A钢板正撞击下的弹道极限速度和极限贯穿厚度范围.采用Autodyn软件进行了同试验条件下的数值仿真,仿真模型被验证后,通过仿真获得了极限贯穿厚度范围,同时分析了钨球正撞击侵彻过程中的能量转换规律.基于能量守恒,建立了钨球对低碳钢板正撞击下极限贯穿厚度的计算模型.采用所建立的计算模型计算得到:Φ6.0mm(93W)、Φ7.0mm(93W)、Φ6.0mm(95 W)和Φ7.5mm(95 W)4种钨球正撞击下Q235A钢板的极限贯穿厚度分别为16.95,19.17,17.30,21.50mm,计算结果与试验和数值仿真所获得范围误差不大于10%.研究结果为杀爆战斗部毁伤元的设计提供了基础数据以及方法支撑.

关键词：高速侵彻动力学极限贯穿厚度钨球低碳钢