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Intermediate-mass black holes in Green pea galaxies(IMBH-GP)I:A candidate sample from LAMOST and SDSS

Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 147-161页

作者： Ruqiu Lin Zhen-Ya Zheng Fang-Ting Yuan Jun-Xian Wang Chunyan Jiang Ning Jiang Lingzhi Wang Linhua Jiang Xiang Ji Shuairu Zhu Xiaodan Fu Key Laboratory for research in Galaxies and Cosmology Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghai 200030China School of Astronomy and space Sciences University of Chinese Academy of SciencesBeijing 100049China CAS Key Laboratory for research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China Chinese Academy of Sciences South America Center for Astronomy(CASSACA) National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Kavli institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Department of Astronomy School of PhysicsPeking UniversityBeijing 100871China

The scaling relation of central massive black holes(M_(BH)s)and their host galaxies is well-studied for supermassive BHs(SM_(BH)s,M_(BH)≥10^(6)M_(⊙)).However,this relation has large uncertainties in the mass range of the intermediate-mass BHs(IM_(BH)s,M_(BH)~10^(3)-10^(6)M_(⊙)).Since Green pea(GP)galaxies are luminous compact dwarf galaxies,which may be likely to host less massive SM_(BH)s or even IM_(BH)s,we systematically search for M_(BH)s in a large sample of 2190 GP galaxies at z<0.4,selected from LAMOST and SDSS spectroscopic ***,we report a newly discovered sample of 59 M_(BH) candidates with broad Hα*** sample has a median stellar mass of 108.83±0.11M_(⊙)and hosts M_(BH)s with single-epoch virial masses ranging from M_(BH)~10^(4.7)to 10^(8.5)M_(⊙)(median 105.85±0.64M_(⊙)).Among the 59 M_(BH) candidates,36 have black hole masses M_(BH)≤10^(6)M_(⊙)(IM_(BH) candidates),one of which even has M_(BH)■10^(5)M_(⊙).We find that the M_(BH)-M_(*)relation of our M_(BH) sample is consistent with the M_(BH)-M_(bulge)relation for SM_(BH)s,while is above the M_(BH)-M_(*)relation for M_(BH)s in dwarf galaxies in the same mass ***,we show that 25 M_(BH) candidates,including 4 IM_(BH) candidates,have additional evidence of black hole activities,assessed through various methods such as the broad-line width,BPT diagram,mid-infrared color,X-ray luminosity,and radio *** studies show that it is very promising to find IM_(BH)s in GP galaxies,and the BH sample so obtained enables us to probe the connection between the M_(BH)s and compact dwarf galaxies in the low-redshift Universe.

关键词： SMBHs IMBHs Green pea galaxies compact dwarf galaxies

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Tunable polarization holographic gratings obtained by varying the ratio of intensities of the recording beams

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Photonics research 2024年第4期12卷 749-754页

作者： HONG CHEN ZIYAO LYU CHANGSHUN WANG State Key Laboratory of Advanced Optical Communication Systems and Networks School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of space-Ground Integrated Information technology Beijing Institute of Satellite Information EngineeringBeijing 100095China

Polarization holography has been extensively applied in many fields, such as optical science, metrology, and biochemistry, due to its property of polarization modulation. However, the modulated polarization state of diffracted light corresponds strictly to that of incident light one by one. Here, a kind of tunable polarization holographic grating has been designed in terms of Jones matrices, and intensity-based polarization manipulation has been realized experimentally. The proposed tunable polarization holographic grating is recorded on an azobenzene liquid-crystalline film by a pair of coherent light beams with orthogonal polarization states and asymmetrically controlled intensities. It is found that the diffracted light can be actively manipulated from linearly to circularly polarized based on the light intensity of the recording holographic field when the polarization state of incident light keeps constant. Our work could enrich the field of light manipulation and holography.

关键词： holographic recording Polarization

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Continuous-flow enzymatic synthesis of chiral lactones in a three-dimensional microfluidic reactor

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Chinese Chemical Letters 2024年第3期35卷 299-303页

作者： Xuelei Deng Meng Fan Miao Wu Xiaoyan Zhang Ya Cheng Jianye Xia Yingping Zhuang Weiping Zhu Xuhong Qian Yunpeng Bai State Key Laboratory of Bioreactor Engineering Shanghai Collaborative Innovation Center for BiomanufacturingEast China University of Science and TechnologyShanghai 200237China The Extreme Optoelectromechanics Laboratory School of Physics and Materials ScienceEast China Normal UniversityShanghai 200241China Tianjin institute of Industrial Biotechnology Chinese Academy of SciencesTianjin 300308China

A new continuous-flow process for the enzymatic synthesis of optically pureγ-lactones,which are used as flavors and fragrances in the food and cosmetic industries,was developed in a three-dimensional microfluidic *** microchannels(175 mm in length,0.9 mm in depth,and 1.72 mL in volume)were carved precisely inside a single borosilicate glass(90 mm×75 mm×12 mm)with ultrafast femtosecond laser *** flow field analysis and reaction simulation showed that the mixing of substrates and enzymes was enhanced,allowing the adjustment of residence time in a wide ***_(V4),a carbonyl reductase with excellent catalytic activity and enantioselectivity towardγ/δ-keto acids,was employed for the asymmetric synthesis of various chiral lactones.30 mmol/L(R)-γ-decalactone(3g)can be obtained in 26 s with a space-time yield(STY)up to 16,877 g L^(-1)d^(-1),which is 14.4 times higher than the highest STY of batch reaction reported *** continuous-flow process was applied to the synthesis of 6 chiral *** addition,the scaled-up synthesis of 3g was carried out in 6 cascade microreactors continuously for 6 h,demonstrating the feasibility and stability of the 3D continuous-flow process in enzymatic synthesis of optically pure compounds.

关键词： Continuous-flow Flow chemistry Microreactor Biocatalysis Carbonyl reductase Asymmetric reduction

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A global model for evaluating discharge characteristics and performance of hollow cathodes

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Chinese Journal of Aeronautics 2024年第9期37卷 72-84页

作者： Feng TIAN Long MIAO Qimeng XIA Zhiwen WU Ningfei WANG Xiao HOU School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Chongqing Innovation Center Beijing Institute of TechnologyChongqing 404100China

Hollow cathode,with the highest plasma density,current density,and temperature,becomes one of the most important components in the electro-thruster *** the electric-propulsion thruster performance is directly related to the ionization rate,reliability,and lifetime of the hollow cathode,this paper develops a global model to study the effects of discharge current,gas flow rate,and gas species on the discharge characteristics in the insert and orifice regions of the hollow *** emitter wall temperatures of hollow cathodes predicted by the global model are compared with experimental results from NSTAR thruster neutralization cathodes,confirming the model's *** influence of hollow cathode emitter material and structure sizes on the plasma parameters in the internal regions was also *** simulation results show that there is an optimal matching relationship between the discharge current and gas flow rate to guarantee the maximum ionization *** optimal working region for the hollow cathode has been deter-mined under different energetic,regime and structural *** global model established in this paper can quickly determine the key structure and operating parameters of hollow cathode at the design stage,and provide the theoretical basis for hollow cathode design and development.

关键词： Hollow cathode Global model Electric propulsion Discharge characteristics Optimal matching relationship

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基于动力学的螺旋桨影响下的船舶推进系统声振特性研究

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Acta Mechanica Sinica 2024年第2期40卷 214-236页

作者：徐江海薛林邹冬林焦春晓塔娜饶柱石 School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China institute of Vibration Shock and NoiseState Key Laboratory of Mechanical System and VibrationShanghai Jiao Tong UniversityShanghai200240China Tianjin Navigation Instruments research institute Tianjin300131China

船舶推进系统稳定性受到施加在螺旋桨上的负载及其本身的惯性效应的综合影响.论文聚焦非对称动力输入下的双缸推进系统,旨在通过理论建模、数值仿真和实验验证探究推进系统的动力学行为及其影响因素.首先,考虑传动系统的啮合刚度、齿面... 详细信息

船舶推进系统稳定性受到施加在螺旋桨上的负载及其本身的惯性效应的综合影响.论文聚焦非对称动力输入下的双缸推进系统,旨在通过理论建模、数值仿真和实验验证探究推进系统的动力学行为及其影响因素.首先,考虑传动系统的啮合刚度、齿面摩擦、齿侧间隙、非对称激励等时变、非线性因素,建立推进系统非线性动力学模型.其次,采用数值方法研究桨端负载及其惯性效应对于推进系统稳定性和振动响应的影响,揭示多参数影响下的系统复杂的动力学行为.最后,基于理论模型,构建并联推进系统综合实验平台,进一步研究了负载和惯性效应对于推进系统声振特性的影响.研究结果对于从动力学角度进行系统动力参数的设计和螺旋桨的结构优化具有积极意义.

关键词：船舶推进系统惯性效应综合实验平台传动系统声振特性非线性动力学模型动力参数齿侧间隙

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Bunching enhancement for coherent harmonic generation by using phase merging effects

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Matter and Radiation at Extremes 2024年第5期9卷 10-21页

作者： Ke Feng Kangnan Jiang Runshu Hu Shixia Luan Wentao Wang Ruxin Li State Key Laboratory of High Field Laser Physics and CAS Center for Excellence in Ultra-intense Laser Science Shanghai Institute of Optics and Fine Mechanics(SIOM)Chinese Academy of Sciences(CAS)ShanghaiPeople’s Republic of China School of Physical Science and technology ShanghaiTech UniversityShanghaiPeople’s Republic of China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijingPeople’s Republic of China

In this paper,promising but simple schemes are investigated to enhance the micro-bunching of relativistic electron beams for coherent harmonic generation(CHG)by using phase merging *** contrast to the standard CHG scheme,two specially designed dispersion sections(DSs)are adopted with the DS-modulator–DS *** phase space of the e beam is appropriately coupled in the first DS,and the electrons within one seed wavelength can merge to the same phase with a matched second ***-bunching of the e beam can thus be enhanced by a large margin with much higher-harmonic *** e beams from laser wakefield accelerators(LWFAs)as an example,start-to-end simulations are performed to show the effectiveness and robustness of the proposed schemes with several *** beam current can be optimized to several tens to hundreds of kiloamperes,and the radiation power reaches hundreds of megawatts in the extreme ultraviolet regime within a 3.5 m-long *** proposed schemes offer new opportunities for future compact free-electron lasers driven by LWFAs and provides prospects for truly compact and widely applicable systems.

关键词： modulator harmonic phase

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基于改进分形方法的齿面磨损故障直齿轮啮合特性分析

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Journal of Central South University 2024年第5期31卷 1619-1636页

作者：刘子濛常成胡昊东马辉张顺豪赵松涛张晓旭彭志科 School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China Key Laboratory of Vibration and Control of Aero-propulsion System Northeastern UniversityShenyang 110819China Harbin Marine Boiler and Turbine research institute Harbin 150078China School of Mechanical Engineering Tongji UniversityShanghai 201804China institute of Vibration Shock&Noise State Key Laboratory of Mechanical System and VibrationShanghai Jiao Tong UniversityShanghai 200240China

考虑实际的轮齿表面微观形貌,建立了轮齿间相互作用的三维分形接触模型。结合轮齿承载接触分析方法,考虑轮齿间摩擦力的影响,建立了直齿轮副的时变啮合刚度模型,并通过有限元方法进行了验证。结合Archard磨损模型,考虑齿面粗糙度和摩擦... 详细信息

考虑实际的轮齿表面微观形貌,建立了轮齿间相互作用的三维分形接触模型。结合轮齿承载接触分析方法,考虑轮齿间摩擦力的影响,建立了直齿轮副的时变啮合刚度模型,并通过有限元方法进行了验证。结合Archard磨损模型,考虑齿面粗糙度和摩擦力的影响,分析了齿面磨损故障状态下直齿轮副的啮合特性和磨损深度,同时分析了摩擦力和分形参数对时变啮合刚度和磨损深度的影响。摩擦力导致节线处的时变啮合刚度发生突变。当直齿轮副处于双齿啮合时,摩擦因数的增加和分形维数的降低导致磨损深度的增加和时变啮合刚度的降低。时变啮合刚度随分形维数的变化呈线性变化。分形维数对时变啮合刚度和磨损深度的影响随着磨损周期的增加更为明显,超过了摩擦因数对其的影响。

关键词：直齿轮啮合特性分型接触齿面摩擦力磨损故障

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MAVEN observation of magnetosonic waves in the Martian magnetotail region

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Earth and Planetary Physics 2024年第2期8卷 317-325页

作者： ShangChun Teng JiCheng Sun JiaWei Gao Y.Harada Markus Fraenz DeSheng Han State Key Laboratory of Marine Geology School of Ocean and Earth ScienceTongji UniversityShanghai 200092China MNR Key Laboratory for Polar Science Polar Research Institute of ChinaShanghai 200136China Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Geophysics Kyoto UniversityKyotoJapan Max-Planck-institute for Solar System research GoettingenGermany

Magnetosonic waves are an important medium for energy transfer in collisionless space *** waves have been widely investigated in the upstream of the bow shock at *** waves are believed to originate from pickup ions or reflected *** utilizing MAVEN spacecraft data,we have observed the occurrence of quasi-perpendicularly propagating magnetosonic emissions near the proton gyrofrequency in the Martian magnetotail *** plasma waves are associated with a significant enhancement of proton and oxygen *** excited magnetosonic waves could possibly heat the protons through resonance and facilitate the ionospheric plasma *** results could be helpful to better understand the Mars’magnetospheric dynamics and offer insights into possible energy redistribution between waves and plasma in the Martian nightside magnetosphere.

关键词： Martian magnetotail region magnetosonic waves proton escape

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Comprehensive,Continuous,and Vertical Measurements of Seawater Constituents with Triple-Field-of-View High-Spectral-Resolution Lidar

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research 2024年第2期2023卷 191-201页

作者： Kai Zhang Yatong Chen Hongkai Zhao Zhongping Lee Emmanuel Boss Iwona Stachlewska Davide Dionisi Cedric Jamet Paolo D.Girolamo Aleksey Malinka Chengchong Jiang Hongda Wu Lingyun Wu Feitong Chen Xiaolei Zhu Nanchao Wang Chuxiao Chen Qun Liu Lan Wu Yudi Zhou Weibiao Chen Dong Liu Ningbo research institute State Key Laboratory of Modern Optical InstrumentationCollege of Optical Science and EngineeringZhejiang UniversityHangzhou 310027China ZJU-Hangzhou Global Scientific and Technological lnnovation Center Zhejang UniversityHangzhou 311200China Donghai Laboratory.Zhoushan 316021 China State Key Lab of Marine Environmental Science College of Ocean and Earth SciencesXiamen UniversityXiamen 361102China School of Marine Sciences University of MaineOronoME 04469-5741USA Faculty of Physics University of WarsawWarsaw 02093Poland institute of Marine Sciences Italian National Research CouncilRome 00133Italy Universitédu Littoral Cote d'Opale CNRSUniv.LilleIRDUMR 8187-LOG-Laboratoire d'Oceanologie et de GéosciencesWimereux F-6293 Francen institute Scuola di Ingegneria Universita della BasilicataPotenza 85100Italy institute of Physics National Academy of Sciences of BelarusMinsk 220072Belarus Key Laboratory of space Laser Communication and Detection technology Shanghai lnstitute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Inteligent Optics&Photonics research Center Jiaxing Research Institute Zhejiang UniversityJiaxing 314000China Jiaxing Key Laboratory of Photonic Sensing&Intelligent Imaging Jiaxing 314000China

Measuring the characteristics of seawater constituent is in great demand for studies of marine ecosystems and ***,existing techniques based on remote sensing or in situ samplings present various tradeoffs with regard to the diversity,synchronism,temporal-spatial resolution,and depth-resolved capacity of their data ***,we demonstrate a novel oceanic triple-field-of-view(FOV)high-spectral-resolution lidar(HSRL)with an iterative retrieval *** technique provides,for the first time,comprehensive,continuous,and vertical measurements of seawater absorption coefficient,scattering coefficient,and slope of particle size distribution,which are validated by simulations and field ***,it depicts valuable application potentials in the accuracy improvement of seawater classification and the continuous estimation of depth-resolved particulate organic carbon *** triple-FOV HSRL with high performance could greatly increase the knowledge of seawater constituents and promote the understanding of marine ecosystems and biogeochemistry.

关键词： lidar Vertical seawater

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Coherent Doppler lidar wind retrieval for a typhoon based on the genetic simulated annealing algorithm

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Chinese Optics Letters 2024年第4期22卷 1-7页

作者：刘珍原禄城汤杰张云鹏刘继桥竹孝鹏杨巨鑫时伟陈卫标 Aerospace Laser technology and Systems Department Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBejing 100049China shanghai Typhoon institute China Meteorological AdministrationShanghai 200030China

A method of spectrum estimation based on the genetic simulated annealing(GSA)algorithm is proposed,which is applied to retrieve the three-dimensional wind field of typhoon Nangka observed by our research *** to the genetic algorithm(GA),the GSA algorithm not only extends the detection range and guarantees the accuracy of retrieval results but also demonstrates a faster retrieval *** results indicate that both the GA and GSA algorithms can enhance the detection range by 35%more than the least squares ***,the convergence speed of the GSA algorithm is 17 times faster than that of the GA,which is more beneficial for real-time data processing.

关键词： coherent Doppler lidar three-dimensional wind field retrieval genetic simulated annealing algorithm spectrum estimation typhoon

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