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chinese Journal of Aeronautics 2024年第10期37卷 83-102页

作者： Ruoye XIAO dong SUN jian yu School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China State Key Laboratory of Aerodynamics Mianyang 621000China

Shock wave/boundary layer interaction in a 24°turning angle of the compression ramp at Mach number 2.9 controlled by steady microjet is investigated using direct numerical *** different jet spacings which are termed as sparse,moderate and dense are considered,and the induced vortex system and shock structures are compared.A moderate jet spacing configuration is found to generate counter-rotating vortex pairs that transport high-momentum fluid towards the vicinity of wall and strengthen the boundary layer to resist separation,reducing the separation *** dense jet spacing configuration creates a larger momentum deficit region,reducing the friction downstream of the *** of pressure and pressure gradient reveals that dense jet spacing configuration reduces the intensity of separation *** impact of varying jet spacings on the turbulent kinetic energy transport mechanism is also investigated by decomposing the budget terms in the transport ***,the spectral characteristics of the separation region are studied using power spectral density and dynamic mode decomposition methods,revealing that moderate jet spacing configuration suppresses low-frequency fluctuations in the separation region.

关键词： Shock wave/boundary layer interaction Compression ramp Steady microjet Different jet spacings Direct numerical simulation

Characteristics of air particulate matter and their sources in urban and rural area of beijing, china

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Journal of Environmental sciences 2000年第4期12卷 402-409页

作者： YANG Shao jin, dong Jin quan, CHENG bing ru (institute of high energy physics, chinese academy of sciences, beijing 100080, china) institute of high energy physics Chinese Academy of Sciences Beijing 100080 China

During October 1993 and March 1996, the samples of fine and coarse air particulate matter have been collected at representative urban and rural site of beijing with the Gent Stacked Filter Unit Sampler. Instrumental neutron activation analysis (INAA) and proton induced X ray emission (PIXE) method were used to determine the elemental composition of the particulate matter. Average elemental concentrations and enrichment factors were calculated for the fine and coarse size fractions. Based on the particulate matter data obtained at urban and rural site together with the chemical constituents of the aerosol from the different sources are discussed. The results show that the relative particulate mass and elemental concentrations of crustal and pollutant elements in the air particulate matter collected over the urban are higher than rural and winter heating period are higher than in ordinary season. beijing atmosphere is polluted by aerosols from regional and faraway sources. It was noticed that the toxic or harmful elements such as As, Sb, Pb, Cu, Ni, S and Zn were mainly enriched in fine particles with diameter less than 2 μm. A receptor model was used to assess the relative contribution of major air pollution sources at receptor sites in beijing. Trace elements were used as the markers for the above assessment. Factor analysis method was used to identify possible emission sources of air particles. The major sources of dust soil, coal burning, motor vehicle emission, industry emission and refuse incineration were identified.

关键词： atmospheric particulate matter urban rural source aerosol

A Study of Electromagnetic Transition of Δ(1232)Resonance

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Communications in Theoretical physics 2004年第7期 87-89页

作者： dong yu-bing liu jian institute of high energy physics, the chinese academy of sciences, beijing 10003., china

Point form relativistic dynamics of relativistic quantum mechanics is employed to estimate the photonand electroproduction amplitudes of Δ(1232) *** are compared with the non-relativistic work,and thedifferences betw... 详细信息

关键词： relativistic quantum mechanism point form dynamics

Geometry of Broad Line Regions of Active Galactic Nuclei

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chinese Journal of Astronomy and Astrophysics 2008年第1期8卷 50-62页

作者： Xiao-Rong Lü1 Key Laboratory for Particle Astrophysics, institute of high energy physics, chinese academy of sciences, beijing 100049 2 Graduate School of chinese academy of sciences, beijing 100049 Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 Graduate School of chinese academy of sciences Beijing 100049

It has long remained an open question as to the geometry of the broad line region （BLR） in active galactic nuclei （AGNs）. The reverberation mapping technique which measures the response of the broad emission lines to the ionizing continuum, when combined with multiwavelength continuum fitted by sophisticated accretion disks, provides a way of probing the BLR geometry. We analyze a sample of 35 AGNs, which have been monitored by the reverberation mapping campaign. In view of energy budget, the reverberation-based BH masses are found to be in agreement with those obtained by accretion disk models in two thirds of the present sample while the reverberation mapping methods underestimate the BH masses in about one third of objects, as also suggested by CoUin et al. in a recent work. We point out that there are obviously two kinds of BLR geometry, which are strongly dependent on the Eddington ratio, and separated by the value LBol/LEdd - 0.1. These results prefer a scenario of the disk and wind configuration of the BLR and identify the Eddington ratio as the physical driver regulating the wind in the BLR.

关键词： accretion, accretion disks - galaxies active - galaxies Seyfert - quasars general

Feasibility of medical radioisotope production based on the proton beams at china Spallation Neutron Source

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Nuclear Science and Techniques 2024年第6期35卷 26-39页

作者： bing jiang Bin-Bin Tian Han-Tao Jing Qi-Fan dong Spallation Neutron Source Science Center Dongguan 523803China institute of high energy physics Chinese Academy of Sciences(CAS)Beijing 100049China University of chinese academy of sciences Beijing 100049China

The utilization of a proton beam from the china Spallation Neutron Source(CSNS)for producing medical radioisotopes is appealing owing to its high current intensity and high *** medical isotope production based on the proton beam at the CSNS is significant for the development of future radiopharmaceuticals,particularly for theα-emitting *** production yield and activity of typical medical isotopes were estimated using the FLUKA *** results indicate that the 300-MeV proton beam with a power of 100 kW at CSNS-II is highly suitable for proof-of-principle studies of most medical *** particular,this proton beam offers tremendous advantages for the large-scale production of alpha radioisotopes,such as 225Ac,whose theoretical production yield can reach approximately 57 Ci/*** on these results,we provide perspectives on the use of CSNS proton beams to produce radioisotopes for medical applications.

关键词： CSNS proton beam Medical isotope production α-Emitting radionuclides Nuclidic purity analysis

Stepped-up development of accelerator mass spectrometry method for the detection of ^(60)Fe with the HI-13 tandem accelerator

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Nuclear Science and Techniques 2024年第4期35卷 136-143页

作者： Yang Zhang Sheng-Quan Yan Ming He Qing-Zhang Zhao Wen-Hui Zhang Chao-Xin Kan jian-Ming Zhou Kang-Ning Li Xiao-Fei Wang jian-Cheng liu Zhao-Hua Peng Zhuo Liang Ai-Ling Li jian Zheng Qi-Wen Fan yun-Ju Li You-Bao Wang Zhi-Hong Li Yang-Ping Shen Ding Nan Wei Nan yu-Qiang Zhang Jia-Ying-Hao Li Jun-Wen Tian jiang-Lin Hou Chang-Xin Guo Zhi-Cheng Zhang Ming-Hao Zhu yu-Wen Chen yu-Chen jiang Tao Tian Jin-Long Ma Yi-Hui liu Jing-yu dong Run-Long liu Mei-yue-Nan Ma Yong-Shou Chen Wei-Ping liu bing Guo china institute of Atomic energy P.O.Box 275(10)Beijing 102413China College of Science Southern University of Science and TechnologyShenzhen 518055China School of physics Xi’an Jiaotong UniversityXi’an 710049China

The Moon provides a unique environment for investigating nearby astrophysical events such as *** samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides such as^(60)*** this work,we stepped up the development of an accelerator mass spectrometry(AMS)method for detecting^(60)Fe using the HI-13tandem accelerator at the china institute of Atomic energy(CIAE).Since interferences could not be sufficiently removed solely with the existing magnetic systems of the tandem accelerator and the following Q3D magnetic spectrograph,a Wien filter with a maximum voltage of±60 kV and a maximum magnetic field of 0.3 T was installed after the accelerator magnetic systems to lower the detection background for the low abundance nuclide^(60)Fe.A 1μm thick Si_(3)N_(4) foil was installed in front of the Q3D as an energy *** particle detection,a multi-anode gas ionization chamber was mounted at the center of the focal plane of the ***,an^(60)Fe sample with an abundance of 1.125×10^(-10)was used to test the new AMS *** results indicate that^(60)Fe can be clearly distinguished from the isobar^(60)*** sensitivity was assessed to be better than 4.3×10^(-14)based on blank sample measurements lasting 5.8 h,and the sensitivity could,in principle,be expected to be approximately 2.5×10^(-15)when the data were accumulated for 100 h,which is feasible for future lunar sample measurements because the main contaminants were sufficiently separated.

关键词： Accelerator mass spectrometry Wien filter Isobar separation Supernovae Chang'e-5 lunar samples

Nucleon Form Factors and N-A Transitions in a Hypercentral Constituent Quark Model with Meson Cloud

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Communications in Theoretical physics 2007年第3期 539-546页

作者： CHEN Dina-Yong~(1,2) dong yu-bing~(1,+)1 institute of high energy physics,the chinese academy of sciences,beijing 100049,china2 Graduate School of the chinese academy of sciences,beijing 100049,china institute of high energy physics，the chinese academy of sciences，beijing 100049，china Graduate School of the chinese academy of sciences，beijing 100049，china institute of high energy physics，the chinese academy of sciences，beijing 100049，china

We study the nucleon form factors and the nucleon-△(1232)transitions in a framework of hypercentralconstituent quark *** pion meson cloud effect is taken into account *** results show that the pioncloud contributes substantially to the nucleon form factors as well as to the helicity amplitudes of △(1232),and it givesan improved agreement compared to the experimental measurement.

关键词： electromagnetic form factor nucleon and △(1232) hypercentral constituent quark model meson cloud

Assessing structure of Mg_(3)Bi_(2-x)Sb_(x)(0≤x≤2)at pressures below 40 GPa

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Journal of Materiomics 2024年第4期10卷 837-844页

作者： Weiwei dong Wei Xu Zhiying Guo Weishu liu yu Pan Satishkumar Kulkarni Xiaodong Li Konstantin Glazyrin beijing Synchrotron Radiation Facility(BSRF) Institute of High Energy PhysicsChinese Academy of Sciences100049BeijingChina Deutsches Elektronen-Synchrotron DESY Notkestr.8522607HamburgGermany International Centre for Material Science Superstripes RICMASSVia dei Sabelli 119A00185RomeItaly Department of Materials Science and Engineering Southern University of Science and Technology518055ShenzhenChina Max-Planck-institute for Chemical physics of Solids Nöthnitzer Straße 4001187DresdenGermany Centre for X-ray and Nanoscience CXNS Deutsches Elektronen Synchrotron DESYNotkestr.8522607HamburgGermany

Mg_(3)Bi_(2-x)Sb_(x)(0≤x≤2)have gained significant attention due to their potential in thermoelectric(TE)***,there has been much debating regarding their structural properties and phase diagram as a function of pressure,which is crucial for understanding of their TE ***,we investigate a unified phase diagram of Mg_(3)(Bi,Sb)_(2) materials up to 40 GPa at room temperature using high-pressure X-ray *** high-pressure phases with the structural transition succession of P3m1→C2/m→P21/n are observed,which is valid for all Mg_(3)Bi_(2-x)Sb_(x)(0≤x≤2)*** further explore the low-pressure phase P3m1 and report that alloying does not change the quasi-isotropic compression of the unit lattice parameters nor has effect on the anisotropic bond compressibility,as recently reported for the *** study presents a comprehensive picture of Mg3Bi2–xSbx as a function of pressure and chemical composition providing a solid foundation for the future experimental and theoretical studies searching for the most efficient TE compound in Mg_(3)(Bi,Sb)_(2).

关键词： Mg_(3)Bi_(2-x)Sb_(x)(0≤x≤2) Thermoelectric high-pressure Structural evolution

Observation constraints of the hard X-ray modulation telescope HXMT

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Science china(physics,Mechanics & Astronomy) 2010年第S1期53卷 31-35页

作者： LU yu1,2,ZHANG WenZhao3,QU JinLu1,SONG LiMing1,GAO jian3,ZHANG HongMei4 & OU Ge4 1 Key Laboratory of Particle Astrophysics,institute of high energy physics,chinese academy of sciences,beijing 100049,china 2 Graduate University of chinese academy of sciences,beijing 100049,china 3 Department of Astronomy,beijing Normal University,beijing 100875,china 4 Computing Center,institute of high energy physics,chinese academy of sciences,beijing 100049,china Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China Department of Astronomy Beijing Normal University Beijing China Computing Center Institute of High Energy Physics Chinese Academy of Sciences Beijing China

The hard X-ray modulation telescope HXMT is a low orbit X-ray space telescope whose main science goals are to accomplish a hard X-ray all sky survey and to study timing and spectral characteristics of X-ray *** has three kinds of science instruments:the high energy X-ray detector(HE),the medium energy X-ray detector(ME) and the low energy X-ray detector(LE).The observation schedule of HXMT is a key to achieving the science goal of HXMT,and the analysis of the observation constraints is one of the first tasks in making the observation *** paper analyzes how the observation constraints influence the sky visibility and the visible time distribution of X-ray sources and discusses the schedule strategy with regard to the observation constraints.

关键词： HXMT observation constraints sky visibility

Fast prototype and rapid construction of three-dimensional and multi-scaled pitcher for controlled drainage by systematic biomimicry

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International Journal of Extreme Manufacturing 2024年第3期6卷 489-503页

作者： Tao Shen Ning Li Shijie liu Cunlong yu Chengqi Zhang Kang Yang Xingfei Li Ruochen Fang Lei jiang Zhichao dong Research institute for Frontier Science Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education BeijingSchool of ChemistryBeihang UniversityBeijing 100191People’s Republic of China CAS Key Laboratory of Bio-inspired Materials and Interfacial Science Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190People’s Republic of China CAS Center for Excellence in Nanoscience Beijing Key Laboratory of Micro-nano Energy and SensorBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 100083People’s Republic of China School of Future Technology&School of Nanoscience and Engineering University of Chinese Academy of SciencesBeijing 101407People’s Republic of China School of Chemistry and Materials Science University of Science and Technology of China230026 HefeiAnhuiPeople’s Republic of China Suzhou institute for Advanced Research University of Science and Technology of China215123 SuzhouJiangsuPeople’s Republic of China State Key Laboratory of Precision Measuring Technology and Instruments Tianjin University300072 TianjinPeople’s Republic of China

Biomimetic materials that use natural wisdom to solve practical problems are developing *** trend for systematic biomimicry is towards in-situ characterization of naturalcreatures with high spatial ***,rapid reconstruction of digital twin models with the same complex features as the prototype is ***,it faces bottlenecks and limits in fast characterization and fabrication,precise parameter optimization,geometricdeviations control,and quality *** solve these challenges,here,we demonstrate astate-of-the-art method taking advantage of micro-computed tomography and three-dimensional printing for the fast characterization of the pitcher plant Nepenthes x ventrata and fabrication of its biomimetic model to obtain a superior drainage controller with multiscale structures withprecise surface morphology optimization and geometric deviation ***-rupture-based drainage dynamic and mechanisms are characterized by x-ray and high-speed videography,which determines the crucial structures for unique *** the optimized artificial pitchers are further developed into sustained drainage devices with novel applications,such as detection,reaction,and smoke control.

关键词： systematic biomimicry biomimetic materials Micro-CT drainage digital twin