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Rapidly growing primordial black holes as seeds of the massive high-redshift JWST Galaxies

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Science china(Physics,Mechanics & Astronomy) 2024年第10期67卷 139-146页

作者： Guan-Wen Yuan Lei Lei Yuan-Zhu wang Bo wang Yi-Ying wang Chao Chen zhao-Qiang Shen Yi-Fu Cai Yi-Zhong Fan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Deep Space Exploration Laboratory/Department of Astronomy School of Physical SciencesUniversity of Science and Technology of ChinaHefei 230026China Jockey Club Institute for Advanced Study The Hong Kong University of Science and TechnologyHong KongChina

A group of massive galaxies at redshifts of z■7 have been recently detected by the James Webb Space Telescope(JWST),which were unexpected to form at such an early time within the standard Big Bang *** this work,we propose that this puzzle can be explained by the presence of some primordial black holes(PBHs)with a mass of~1000M_(⊙).These PBHs act as seeds for early galaxy formation with masses of~10^(8)-10^(10)M_(⊙)at high redshift,hence accounting for the JWST *** use a hierarchical Bayesian inference framework to constrain the PBH mass distribution models,and find that the Lognormal model with the M_(c)~750M_(⊙)is preferred over other *** rapidly growing BHs are expected to have strong radiation and may appear as high-redshift compact objects,similar to those recently discovered by *** we focused on PBHs in this work,the bound on the initial mass of the seed black holes remains robust even if they were formed through astrophysical channels.

关键词： primordial black hole dark matter halo black hole accretion primordial galaxies

Isotope Method for Confined Groundwater Recharge of the Lower Reaches of the Heihe River,Inner Mongolia,china

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Acta Geologica Sinica(English Edition) 2007年第4期81卷 668-673页

作者： CHEN Jiansheng zhao Xia FAN Zhechao and wang Jiyang 1 State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Hohai University,{2. 2.0098,china 2.Institute of Isotope Hydrology Research,Hohai University,{2. 2.0098,china 3 Institute of Geology and Geophysics,chinese academy of Science,Beijing 100018,china Hohai Univ Stae Key Lab Hydrol Water Resources & Hydraul E Nanjing 210098 Peoples R China Hohai Univ Inst Isotope Hydrol Res Nanjing 210098 Peoples R China chinese Acad Sci Inst Geol & Geophys Beijing 100018 Peoples R China

Environmental isotopes have been appfied to analyze confined groundwater recharge in the lower reaches of the Heihe River, Inner Mongolia. CFC is regarded as a tracer that determines the date of groundwater, the date being less than 45 a. The confined groundwater within the Gurinai area and Ejin Basin other than the surface water of Heihe River might have originated from precipitation from Qilian mountain or/and the Tibetan Plateau. The deep confined groundwater overflows into an upper aquifer and emerges into the ground, forming springs and lakes within the low-lying area. The recharge volume is estimated to be around 400 million-cubic meters.

关键词： isotope CFC Ejin Basin Gurinai groundwater recharge precipitation Qilian mountain

FRAGMENTS OF COMET HYAKUTAKE (C/1996 B2.

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中国科学院上海天文台年刊 2000年 249-250页

作者： Chen Daohan 1 zhao Aidi 1 Wu Oindi 1 Song Yi 1 Fan Yixin 1 Sun Shousheng 2.Zhang Yan 2.Sun Linan 2.(1. purple {2. Observatory, chinese Acadeniy of sciences, nanjing 2.0008) (2. Qingdao Station of purple {2. Observatory, Qingdao

Several fragments of Comet Hyakutake were observed in March and April of 1996. This leads to the impression that the splitting of Comet Hyakutake on a small scale occurred frequently. Data analysis points to a rotatio... 详细信息

关键词： Comet Hyakutake - fragment - rotation period

Changes in overland flow and sediment during simulated rainfall events on cropland in hilly areas of the Sichuan Basin,china

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Progress in Natural Science:Materials International 2009年第11期19卷 1613-1618页

作者： Bin Fu,Yukuan wang~*,Pei Xu,Daojie wang Key Laboratory of {2. Hazards and Earth Surface Process,Institute of {2. Hazards and Environment, The chinese academy of sciences,Chengdu 610041,china Key Laboratory of mountain Hazards and Earth Surface Process Institute of Mountain Hazards and Environment The Chinese Academy of Sciences Chengdu 610041 China

Water and soil loss are the major causes of the land degradation in the hilly area of the Sichuan Basin,china,where purple soil(FAO, Calcaric Regosols) is widely *** research has been conducted on changes in overland flow and sediment during rain events on sloping cropland in this *** this study,45 artificial rainfall events were applied to five runoff plots with slopes of 9%,18%,2.%, 36%,and 47%,*** showed that erosion processes on purple soil of sloping cropland are complex,because the sediment concentration changes with time under different *** to correlations between runoff discharge and sediment concentration, all erosion events were classified into three types:(1) positive correlation;(2. negative correlation;and(3) no *** correlations were dominant,accounting for 60%of all *** intensity,slope gradient,and tillage treatment were the main factors that influenced erosion events.

关键词： Discharge-sediment concentration relationships Water erosion Artificial rainfall Hilly area of the Sichuan Basin purple soil

Simultaneous detection of flare-associated kink oscillations and extreme-ultraviolet waves

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Science china(Technological sciences) 2024年第5期67卷 1592-1601页

作者： LI Dong HOU ZhenYong BAI XianYong LI Chuan FANG Matthew zhao HaiSheng wang JinCheng NING ZongJun Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing210023China Yunnan Key Laboratory of the Solar Physics and Space Science Kunming650216China School of Earth and Space sciences Peking UniversityBeijing100871China National Astronomical Observatories Chinese Academy of SciencesBeijing100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing100049China School of Astronomy and Space Science Nanjing UniversityNanjing210023China Key Laboratory of Modern Astronomy and Astrophysics Ministry of EducationNanjing UniversityNanjing210023China Columbus academy GahannaOhio43230USA Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing100049China Yunnan Observatories Chinese Academy of SciencesKunming650216China

Kink oscillations,which are frequently observed in coronal loops and prominences,are often accompanied by extreme-ultraviolet(EUV)***,much more needs to be explored regarding the causal relationships between kink oscillations and EUV *** this article,we report the simultaneous detection of kink oscillations and EUV waves that are both associated with an X2.1 flare on 2.2. March 03(SOL2.2.-03-03T17:39).The kink oscillations,which are almost perpendicular to the axes of loop-like structures,are observed in three coronal loops and one *** short loop shows in-phase oscillation within the same period of 5.2.min at three *** oscillation could be triggered by the pushing of an expanding loop and interpreted as the standing kink *** lags are found between the kink oscillations of the short loop and two long loops,suggesting that the kink wave travels in different *** kink oscillations of one long loop and the prominence are possibly driven by the disturbance of the coronal mass ejection(CME),and that of another long loop might be attributed to the interaction of the EUV *** onset time of the kink oscillation of the short loop is nearly same as the beginning of an EUV *** fact demonstrates that they are almost *** EUV wave is most likely excited by the expanding loop structure and shows two *** leading component is a fast coronal wave,and the trailing one could be due to the stretching magnetic field lines.

关键词： coronal loops solar flares solar prominence solar oscillations extreme-ultraviolet wave magnetohydrodynamic

CHARACTERISTICS OF SUNSPOT GROUP 5395

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天文研究与技术 1990年第4期 25-27,319页

作者： zhao Aidipurple {2. Observatory, chinese academy of sciences, nanjing 2.0008 china

1 INTRODUCTION The sunspot group 5395 was appeared in the east of the solar disc on 6 March anddisappeared in the west of the solar disc on 2. March in 1989. Its heliographiccoordinates were N34, L2.7. It has been the... 详细信息

关键词： latitude longitude moved appeared everyday spots downward Northeast rotation altitude

Protective benefits of HDPE board sand fences in an environment with variable wind directions on Gobi surfaces:wind tunnel study

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Journal of mountain Science 2024年第10期21卷 3353-3367页

作者： ZHANG Kai TIAN Jianjin LIU Benli zhao Yanhua ZHANG Hailong wang Zhenghui DENG Yuhui College of Civil Engineering Lanzhou Jiaotong UniversityLanzhou 730000China Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

The Golmud-Korla Railway in the Gobi area faces operational challenges due to sand hazards,caused by strong and variable *** study addresses these challenges by conducting wind tunnel tests to evaluate the protective benefits of High Density Polyethylene(HDPE)board sand fences,focusing on their orientation relative to various wind directions(referred to as'wind angle').This study found that the size of the low-velocity zone on the leeward side of the sand fences(LSF)expanded with an increase in the wind angle(WA).At 1H(the height of the sand fence)and 2. positions on the LSF,the wind speed profiles(WSP)exhibited a segmented logarithmic growth,constrained by Z=H at varying *** efficacy of the sand fence in obstructing airflow escalated as WA *** size of the WA has a significant impact on the protective efficiency of HDPE board sand ***,compared to typical sandy surfaces,the rate of sand transport across the Gobi surface diminishes more slowly with height,attributed to the gravel's rebound *** phenomenon allows some sand particles to bypass the fences,rendering them less effective at blocking wind and trapping sand than in sandy *** paper offers scientific evidence supporting the practical use and enhancement of HDPE board sand fences in varied wind conditions.

关键词： Variable wind directions Blown sand control Wind tunnel tests HDPE board sand fences

Quantitative Analysis on the Relationship between Population Distribution and Environment Factors in mountain Area

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Meteorological and Environmental Research 2011年第3期2卷 77-80页

作者： SUN Yu-lian1,2.zhao Yong-tao1,CAO Wei-chao1,2.YU Hui1,MA Yue-wei1,2.1.Institute of mountain Hazards and Environment,{2. academy of sciences,Chengdu 610041,china 2.Graduate University of chinese academy of sciences,Beijing 100049,china

[Objective] The aim was to analyze the relationship between population distribution and environment factors in mountain area quantitatively.[Method] Taking the contiguous area of Sichuan,Yunnan and Guizhou Province as study object,population density and residential point density were chosen as the indices of population distribution,and the quantitative relationship between population distribution and environment factors (including altitude,topography relief amplitude,land use,road network and river network) in mountain area was analyzed.[Result] Altitude and topography relief amplitude in mountain area had obvious negative correlation with population density and residential point density,and the correlation coefficients with population density were-0.731 *** addition,residential points were fewer in the region far from rivers,but there was no obvious correlation between population density and river network *** point density was higher in cultivated land and construction land,and population density had obvious positive correlation with the area proportions of cultivated land and construction land,with the correlation coefficients of 0.895 and 0.72.,***,the more distant from road,the smaller residential point density,and there was obvious positive correlation between population density and road network density,with the correlation coefficient of 0.82..[Conclusion] The study could lay a foundation for the further development of spatiality of population data in study region.

关键词： Population distribution Environmental factors Quantitative analysis mountain area china

Two-dimensional Numerical Model for Debris Flows in the Jiangjia Gully,Yunnan Province

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Journal of mountain Science 2011年第6期8卷 757-766页

作者： PENG Hong zhao Yanxin CUI Peng ZHANG Wanshun CHEN Xuejiao CHEN Xiaoqing College of Water Resources and Hydropower Engineering Wuhan University Wuhan 430072 China School of Resource and Environmental Science Wuhan University Wuhan 43o079 China Institute of mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China

Debris flows are recurrent natural hazards in many mountainous *** paper presents a numerical study on the propagation of debris flows in natural erodible open channels,in which the bed erosion and sedimentation processes are *** on the Bingham fluid theory,a mathematical model of the two-dimensional non-constant debris flow is *** governing equations include the continuity and momentum conservation equations of debris flow,the sediment convection-diffusion equation,the bed erosion-deposition equation and the bed-sediment size gradation adjustment *** yield stress and shear stress components are included to describe the dynamic rheological *** upwind control-volume Finite Volume Method (FVM) is applied to discretize the convection *** improved SIMPLE algorithm with velocity-free-surface coupled correction is developed to solve the equations on non-orthogonal,quadrilateral *** model is applied to simulate a debris flow event in Jiangjia Gully,Yunnan Province and to predict the flow pattern and bed erosion-deposition *** results show the effectiveness of the proposed numercial model in debris flow simulation and potential hazard analysis.

关键词： Debris flow Numerical simulation SIMPLE algorithm Finite Volume Method Hazardanalysis Jiangjia Gully