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秦岭北坡土壤发生特性与系统分类

土壤学报 2002年第2期39卷 227-235页

作者：常庆瑞雷梅冯立孝闫湘西北农林科技大学资源与环境科学系陕西杨陵712100 中国科学院地理研究所北京100101 中国农业科学院土壤肥料研究所北京100081

根据野外调查资料和典型土壤剖面理化性质 ,包括室内化验数据综合分析表明 :秦岭北坡土壤的主要发生特性随海拔高度呈有规律的变化 ,依照《中国土壤系统分类 (修订方案 )》检索 ,土壤垂直带谱结构为

关键词：秦岭北坡土壤特性系统分类垂直带谱土壤发生特性

模拟增温改变川西高山草甸优势植物繁殖物候序列特征

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植物生态学报 2018年第1期42卷 20-27页

作者：张莉王根绪冉飞彭阿辉肖瑶杨阳杨燕中国科学院水利部成都山地灾害与环境研究所成都610041 中国科学院大学北京100049

以西南横断山区高山草甸优势植物种珠芽拳参(Polygonum viviparum)和银叶委陵菜(Potentilla leuconota)为研究对象,将其物候分为花芽期、开花期、凋谢期和种子成熟期4个阶段,每个阶段又分为开始、峰值和结束3个状态。采用开顶式增温箱... 详细信息

以西南横断山区高山草甸优势植物种珠芽拳参(Polygonum viviparum)和银叶委陵菜(Potentilla leuconota)为研究对象,将其物候分为花芽期、开花期、凋谢期和种子成熟期4个阶段,每个阶段又分为开始、峰值和结束3个状态。采用开顶式增温箱进行模拟增温,连续增温4年后,于增温第5年的2016年生长季跟踪调查了模拟增温对珠芽拳参和银叶委陵菜的繁殖物候序列的影响,以探讨高山植物群落对气候变化的响应过程。结果显示,模拟增温后:1)珠芽拳参各物候阶段的持续时间缩短;除凋谢阶段起始、结束期延迟外,其他状态均有不同程度的提前;各阶段的过渡期有不同程度的缩短,繁殖周期缩短;2)银叶委陵菜各物候阶段的持续时间延长;凋谢期结束前各状态(除开花峰值外)表现为不同程度的提前;各阶段过渡期对增温的响应不一致,繁殖周期延长。结果表明:完整的繁殖物候序列能更准确地反映植物物候对气候变暖的响应;植物对环境变化的响应和应对策略存在种间差异,这种差异可能会进一步改变植物群落组成和结构。

关键词：高山草甸气候变化开顶式增温箱珠芽拳参银叶委陵菜繁殖物候

THE UPliFT PROCESS OF QING-ZANG PLATEAU

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地学前缘 2000年第S1期7卷 356-357页

作者： li Yongzhao 1, Wang Yunsheng 1,Lu yan 2[WT5,5”BX](1 Chengdu University of Technology, Chengdu 610059,china 2 Bureau of Geology and Mineral Resource Xizang Autonomous Region, Lhasa 850000,china)

The uplift of Qing—Zang (Qinghai—Tibet) plateau was the most important event in the late Cenozoic, which deeply influenced the environments of the World, especially those of china. Since the uplift is so important and complex that it has been become the research focus of earth science. Nevertheless, the initial time and evolution process of the uplift is still controversial.1\ The initial time of the uplift\;Qing\|Zang plateau is a union geological\|geomorphic unit, which is composed of several geological\|structural units. Each geological\|structural unit has itself exchange history of sea\|continent (basin\|mountain); the exchange time of the different parts differs. Therefore, the initial time of some part of the plateau is not the uplift time of the whole plateau. The plateau is the highland with high height above sea level, little relief of the top, large area and steep boundary. The plateau plane is the paleo\|peneplain, which was formed by the uplift of the plateau after the peneplanation. Therefore, the initial time of the uplift should be counted from the time that the peneplain had been formed.

关键词： Qing—Zang plateau uplift process peneplain

Effects of Different Covering Ways on Emergence Rate of Sophora japonica *** by Direct Seeding

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chinese Forestry Science and Technology 2008年第3期7卷 65-69页

作者： li Qingmei 1 liU yan2 XING Shangjun3 SONG Yumin3 MA Fengyun2 HOU Longyu4 1. Research Institute of Forestry, chinese academy of Forestry, Beijing 100091, P.R. china 2. Forestry College of Shandong Agricultural University, Tai’an 271018, P. R. china 3. Shandong academy of Forestry, Jinan 251000, P. R. china 4. Institute of Botany, chinese academy of sciences, Beijing 1000193, P. R. china

In order to maintain higher emergence rate with direct seeding in Shandong rocky mountain, effects of different covering ways on emergence rate of Sophora japonica L. direct seeding were studied. The results showed that both mulching film and grass cover could effectively increase the moisture content of the soil at the depth of 0-30 cm, contributing to soil moisture conservation and the inhibition of soil evaporation, which created favorable moisture environment for the growth of S. japonica seeds. Both the emergence rate and the seedling height under mulching film had greater improvement and partly enhanced by 26.65% and 6.85 cm respectively, and mulching film also helped S. japonica seeds emerge and ensured the seedling growth. The emergence rate and the seedling height under grass cover had been also raised in some degree, but they were much worse than those under mulching film. The emergence rate and the seedling height under block cover were not significantly increased. So when sowing S. japonica seeds in the spring, mulching film is the best covering way.

关键词： mulching film grass cover block cover open field Sophora Japonica L. seed direct seeding afforestation

VLBI with SKA:Possible Arrays and Astrometric Science

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Research in Astronomy and Astrophysics 2024年第7期24卷 1-33页

作者： Yingjie li Ye Xu Jingjing li Shuaibo Bian Zehao lin Chaojie Hao Dejian liu purple mountain observatory Chinese Academy of SciencesNanjing 210023China University of Science and Technology of china Hefei 230026China

The next generation of very long baseline interferometry(VLBI)is stepping into the era of microarcsecond(μas)astronomy,and pushing astronomy,especially astrometry,to new *** with the Square Kilometre Array(SKA),SKA-VLBI,will increase current sensitivity by an order of magnitude,and reach astrometric precision routinely below 10μas,even challenging 1μ*** advancement allows precise parallax and proper motion measurements of various celestial *** improvements can be used to study objects(including isolated objects,and binary or multiple systems)in different stellar stages(such as star formation,main-sequence stars,asymptotic giant branch stars,pulsars,black holes,white dwarfs,etc.),unveil the structure and evolution of complex systems(such as the Milky Way),benchmark the international celestial reference frame,and reveal cosmic ***,the theory of general relativity can also be tested with SKA-VLBI using precise measurements of light deflection under the gravitational fields of different solar system objects and the perihelion precession of solar system objects.

关键词： astrometry-parallaxes-stars kinematics and dynamics-ISM kinematics and dynamics-Galaxy kinematics and dynamics-galaxies kinematics and dynamics-gravitation

A compact multi-pixel superconducting nanowire single-photon detector array supporting gigabit space-to-ground communications

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light(Science & Applications) 2024年第2期13卷 254-266页

作者： Hao Hao Qing-Yuan Zhao yang-hui Huang Jie Deng Fan yang Sai-Ying Ru Zhen liu Chao Wan Hao liu Zhi-Jian li Hua-Bing Wang Xue-Cou Tu La-Bao Zhang Xiao-Qing Jia Xing-Long Wu Jian Chen lin Kang Pei-Heng Wu Research Institute of Superconductor Electronics(RISE) School of Electronic Science and EngineeringNanjing UniversityNanjingJiangsu 210023China purple mountain Laboratories NanjingJiangsu 211111China Hefei National Laboratory HefeiAnhui 230088China National Laboratory of Solid State Microstructures and Department of Physics Nanjing UniversityNanjing 210023China

Classical and quantum space-to-ground communications necessitate highly sensitive receivers capable of extracting information from modulated photons to extend the communication distance from near-earth orbits to deep space *** achieve gigabit data rates while mitigating strong background noise photons and beam drift in a highly attenuated free-space channel,a comprehensive design of a multi-functional detector is *** this study,we present an innovative compact multi-pixel superconducting nanowire single-photon detector array that integrates near-unity detection efficiency(91.6%),high photon counting rate(1.61 Gcps),large dynamic range for resolving different photon numbers(1-24),and four-quadrant position sensing function all within one ***,we have constructed a communication testbed to validate the advantages offered by such an *** 8-PPM(pulse position modulation)format communication experiments,we have achieved an impressive maximum data rate of 1.5 Gbps,demonstrating sensitivities surpassing previous benchmarks at respective *** incorporating photon number information into error correction codes,the receiver can tolerate maximum background noise levels equivalent to 0.8 photons/slot at a data rate of 120 Mbps—showcasing a great potential for daylight operation ***,preliminary beam tracking tests were conducted through open-loop scanning techniques,which revealed clear quantitative dependence indicating sensitivity variations based on beam *** on the device characterizations and communication results,we anticipate that this device architecture,along with its corresponding signal processing and coding techniques,will be applicable in future space-to-ground communication tasks.

关键词： photon supporting correction

Microlensing bias on the detection of strong lensing gravitational wave

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Science china(Physics,Mechanics & Astronomy) 2024年第6期67卷 156-165页

作者： Xikai Shan Xuechun Chen Bin Hu Guoliang li Institute for Frontier in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Department of Astronomy Beijing Normal UniversityBeijing 100875China purple mountain observatory Chinese Academy of SciencesNanjing 210023China

Identifying strong lensing gravitational wave(SLGW)events is of utmost importance in astrophysics as we approach the historic first detection of SLGW amidst the growing number of gravitational wave(GW)***,one crucial method for identifying SLGW signals involves assessing the overlap of parameters between two ***,the distribution of discrete matter,such as stars and sub-halos,within the strong lensing galaxy can imprint a wave optical(WO)effect on the SLGW *** frequency dependent imprints introduce biases in parameter estimation and impact SLGW *** this study,we assess the influence of the stellar microlensing field embedded in a strong lensing *** findings demonstrate that the WO effect reduces the detection efficiency of SLGW by 5%-50%for various false alarm probabilities per pair(FAPper pair).Specifically,at an FAPper pairof 10^(-5),the detection efficiency decreases from~10%to~5%.Consequently,the presence of the microlensing field can result in missing half of the strong lensing ***,the microlensing WO effect introduces a noticeable bias in intrinsic parameters,particularly for chirp mass and mass ***,it has tiny influence on extrinsic *** all parameters,~30%of events exhibit a 1σparameter bias,~12%exhibit a 2σparameter bias,and~5%exhibit a 3σparameter bias.

关键词： gravitational wave gravitational strong lensing gravitational micro lensing wave optical effect

Ouabain stimulates ANP secretion via endothelin-ETB receptor mediated pathway in beating rabbit atria

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Ouabain stimulates ANP secretion via endothelin-ETB receptor...

中国生理学会第23届全国会员代表大会暨生理学学术大会

作者： li-Ping liU~1,Hong LAN~1,li YU~1,Hai-yan li~1,Xun CUI~(1,2,*) 1 Department of Physiology,School of Basic Medical sciences,yanbian University,yanji 133000,china 2 Key Laboratory of Organism Functional Factors of the Changbai mountain,Ministry of Education,yanbian University,yanji 133002,china

Objective:Ouabain had been reported to increase the secretion of ANP in *** purpose of the present study was to investigate underlying mechanisms of ouabain-stimulated ANP ***:A perfused, beating rabbit atrial model was *** and ET-1 levels in the atrial perfusates were measured by radioimmnoassay. Results:Ouabain(3μmol/L and 6μmol/L respectively) significantly increased atrial ANP secretion by dose-dependant manner and the endothelin-1(ET-1) levels also increased by *** inhibitor of L-type Ca channel nifedipine(1.0μmol/L) completely inhibited ouabian-increased ANP secretion without change of ouabain-induced atrial ***-R7943(3.0μmol/L),an inhibitor of Na-Ca exchanger,completely blocked the effect of ouabain-increased atrial dynamics but failed to modulate ouabain-increased ANP ***-1 significantly stimulated atrial ANP release in a dose-response *** effects of ET-1 and ouabain on ANP secretion were blockade by BQ 788(0.3μmol/L),an inhibitor of ET-1 B receptor(ET),but not BQ 123(0.3μmol/L),an inhibitor of ET-1 A receptor(ET).Conclusions:Ouabain significantly stimulated atrial ANP secretion with increased atrial dynamics and the ET-1-regulated ANP secretion via ET receptor was involved in it.

关键词： ANP ET-1 ET receptor L-type Ca2+ channel Na+-Ca2+ exchanger.

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振动Kuzmin盘中恒星的运动性质

天文学报 1997年第2期38卷 119-128页

作者：傅燕宁孙义燧南京大学天文系

本文研究振动盘中恒星的运动性质．所采用的势模型为它由一种具简单径向振动模态的Kuzmin盘和一种对数晕共同产生．得到的主要结论是：（1）恒星存在稳定且有序的近圆轨道；（2）盘振动对角动量较小的恒星及远离近圆轨道的恒星影响较大... 详细信息

本文研究振动盘中恒星的运动性质．所采用的势模型为它由一种具简单径向振动模态的Kuzmin盘和一种对数晕共同产生．得到的主要结论是：（1）恒星存在稳定且有序的近圆轨道；（2）盘振动对角动量较小的恒星及远离近圆轨道的恒星影响较大；（3）盘中大部分恒星的运动是有序的；（4）远离近圆轨道的恒星一般作混沌运动，并且最终可能逃逸，但在一个Hubble时间内实际逃逸的恒星比例较小；（5）盘振动可能是振动Kurmin盘中某些星团形成并长期维持的机制之一，盘振动幅度越大，盘中星团数目可能越多；在同一个星系盘中，角动量越大的星团数目可能越少．

关键词：振动盘恒星运动性质星系振动天体力学