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领导者结构高原对辱虐管理的诱发研究:领导者特征与组织政治氛围的调节效应 被引量:6
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作者 李澄锋 田也壮 +1 位作者 葛晶晶 孟炎 《南京航空航天大学学报(社会科学版)》 2013年第1期45-51,71,共8页
在职位晋升角逐中挫败,极度依赖权力并渴望权力扩张的管理者面临职业生涯的"冰冻期",会对下属表现敌意领导行为吗?管理者结构高原和辱虐管理是否存在因果关系?本研究通过对黑龙江两家大型制造企业的216份管理者和员工配对样... 在职位晋升角逐中挫败,极度依赖权力并渴望权力扩张的管理者面临职业生涯的"冰冻期",会对下属表现敌意领导行为吗?管理者结构高原和辱虐管理是否存在因果关系?本研究通过对黑龙江两家大型制造企业的216份管理者和员工配对样本的层级回归分析发现,领导者结构高原和辱虐管理显著正相关,组织政治氛围和敌意归因偏差对二者的关系有显著的调节效应。 展开更多
关键词 辱虐管理 结构高原 组织政治氛围 调节效应
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大陆边缘反S状造山带三维模式兼论青藏高原结构与隆升 被引量:5
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作者 李东旭 《地质力学学报》 CSCD 2007年第1期31-41,共11页
文中根据北美大陆西南边缘造山带的构造地貌及新构造运动特征,建立了反S状大陆边缘造山带的三维构造力学模式,指出阿拉斯加地区为弧形右旋剪切隆升造山带;科迪勒拉造山带为直线右旋走滑造山带;马德雷山以南,延至加勒比海为一左旋沉降‘... 文中根据北美大陆西南边缘造山带的构造地貌及新构造运动特征,建立了反S状大陆边缘造山带的三维构造力学模式,指出阿拉斯加地区为弧形右旋剪切隆升造山带;科迪勒拉造山带为直线右旋走滑造山带;马德雷山以南,延至加勒比海为一左旋沉降‘旋扭沟-弧-盆系统’。以此模式检验欧亚大陆南缘造山带,确定从阿尔卑斯经扎格罗斯、喜马拉雅至印度尼西亚蜿蜒曲折的山链是由四个反S状造山带连锁而成,导致它们的分解为四个构造体系的原因,与南半球冈瓦纳大陆裂解有关。依据上述的区域构造规律,作者认为青藏高原内部结构的原型为旋扭沟-弧-盆系统,属帕米尔—喀喇昆仑—喜马拉雅反S状造山带尾弧的组成部分。后经印度板块俯冲、青藏—三江—印度尼西亚反S状造山带头部弧右旋隆升两组动力系统叠加结果。 展开更多
关键词 反S状旋扭造山带 旋扭沟-弧-盆系统 青藏高原结构与隆升 大陆边缘造山带
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高校教师职业高原结构及影响结果研究 被引量:1
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作者 刘玉 《湖南工程学院学报(社会科学版)》 2015年第1期31-33,共3页
高校教师职业高原是高校教师在职业生涯发展的中期或者某一阶段出现的职业渠道越来越窄、发展机会越来越少的一种困境。研究首先对职业生涯的高原理论进行了系统分析,并在此基础上深入探讨高校教师的职业高原结构组成,以及职业高原现象... 高校教师职业高原是高校教师在职业生涯发展的中期或者某一阶段出现的职业渠道越来越窄、发展机会越来越少的一种困境。研究首先对职业生涯的高原理论进行了系统分析,并在此基础上深入探讨高校教师的职业高原结构组成,以及职业高原现象所产生的影响。 展开更多
关键词 高校教师 职业高原 职业高原结构
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职业高原的结构与测量 被引量:4
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作者 林长华 《湖湘论坛》 2007年第4期102-103,共2页
本文着重介绍了国内外学者在职业高原的结构与测量方面的研究成果。这些研究成果的介绍有助于个体或组织更好地应对职业高原现象。
关键词 职业高原 职业高原结构 职业高原测量
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职业高原对企业人才流失的影响分析
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作者 高立军 《陕西教育(高教版)》 2009年第3期117-117,共1页
本论文以理论和实证相结合的研究方式,通过对西安地区的企业人才进行抽样调查,并对调查数据进行数理统计分析,验证了职业高原与人才流失的相关关系。
关键词 职业高原 结构高原 内容高原 生活高原 人才流失
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用CloudSat/CALIPSO资料分析亚洲季风区和青藏高原地区云的季节变化特征 被引量:59
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作者 汪会 罗亚丽 张人禾 《大气科学》 CSCD 北大核心 2011年第6期1117-1131,共15页
利用2006年9月至2009年8月的CloudSat/CALIPSO资料,分析了东亚季风区(EAMR)、印度季风区(IMR)、西北太平洋季风区(WNPMR)和青藏高原地区(TPR)的云量和云层垂直结构(包括云层的垂直位置、物理厚度、相邻云层间的垂直距离和雷达反射率垂... 利用2006年9月至2009年8月的CloudSat/CALIPSO资料,分析了东亚季风区(EAMR)、印度季风区(IMR)、西北太平洋季风区(WNPMR)和青藏高原地区(TPR)的云量和云层垂直结构(包括云层的垂直位置、物理厚度、相邻云层间的垂直距离和雷达反射率垂直分布)及其季节变化特征,进一步分析了亚洲季风区低云量的分布及其与对流层低层稳定性(LTS)的相关。有如下结论:(1)这期间,EAMR、IMR、WNPMR和TPR总云量分别为69%、72%、83%和69%,其中单层云占56%(IMR和WNPMR)至77%(TPR),多层云中二层和三层云合起来占95%以上。IMR的总云量在夏季(>90%)明显高于冬季(约50%),EAMR和TPR春夏季略高于秋冬季,而WNPMR总云量的季节变化不大。(2)同属热带季风区的IMR和WNPMR全年都有底部在10km以上的冰晶云,其月平均云量为20%(冬季)~70%(夏季);海洋边界层云在WNPMR全年较常见(月平均云量为20%~40%),而IMR的低云主要出现在夏季(20%~40%);属副热带季风区的EAMR云层主要位于对流层中低层,10km以上高云仅在夏季较多(30%左右),但其发生频率和垂直位置相对IMR和WNPMR的高云(12~16km高度的云量为60%~70%)较低;TPR的云主要位于4~11km,等高度上云内滴谱较宽。(3)云顶在4km以下的低云在亚洲季风区的分布在春秋季相似、夏冬季差异较大,冬季低云量最多,主要分布在西北太平洋、中国大陆南部及其以东的洋面和日本附近地区,低云量为45%~70%;低云量与LTS的相关性在冬季不强,而其他季节相关性较好。(4)这四个地区都以薄云为主,有30%~40%的云层物理厚度小于1km,而且多层云中相邻云层间的垂直距离约有10%小于1km,说明现有大气环流模式需要提高垂直分辨率。 展开更多
关键词 亚洲季风区青藏高原云量云垂直结构
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职业生涯高原影响因素研究及启示 被引量:2
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作者 赵梅 张伶 李霞 《科学学与科学技术管理》 CSSCI 北大核心 2007年第8期189-192,共4页
传统上讲,我们一直用"晋升次数"衡量个体的职业生涯是否成功。但是随着组织结构重组和扁平化,空缺职位变得很少。这就造成员工垂直晋升越来越难,大量员工在更小的年龄进入职业生涯高原期[1]。而挖掘出职业生涯高原影响因素对... 传统上讲,我们一直用"晋升次数"衡量个体的职业生涯是否成功。但是随着组织结构重组和扁平化,空缺职位变得很少。这就造成员工垂直晋升越来越难,大量员工在更小的年龄进入职业生涯高原期[1]。而挖掘出职业生涯高原影响因素对于企业和员工均有很重要的意义。 展开更多
关键词 职业生涯高原 职业生涯高原结构 职业生涯高原影响因素
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Cloud vertical structures associated with precipitation magnitudes over the Tibetan Plateau and its neighboring regions 被引量:7
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作者 YAN Ya-Fei WANG Xiao-Cong LIU Yi-Min 《Atmospheric and Oceanic Science Letters》 CSCD 2018年第1期44-53,共10页
Cloud vertical structures and precipitation over the Tibetan Plateau (TP) are analyzed and compared with its neighboring land and tropical oceans based on CloudSat/CALIPSO satellite measurements and TRMM precipitati... Cloud vertical structures and precipitation over the Tibetan Plateau (TP) are analyzed and compared with its neighboring land and tropical oceans based on CloudSat/CALIPSO satellite measurements and TRMM precipitation data. Results show that the TP generally has a compression effect on cloud systems, as manifested by a shrinking cloud depth and lowering cloud top. Precipitation is weaker over the TP than its neighboring regions and exhibits large seasonal variations. In summer, cloud ice particles over the TP are mostly located at lower altitude (5-10 km), with a larger variability of sizes and aggregation (particle number concentration) under no-rain conditions compared to other regions. Ice water content becomes abundant and the number concentration tends to be dense at higher altitudes when precipitation is enhanced. However, even for heavy rainstorms, the aggregation is most likely between 100 and 250 L-1, whereas it can reach as high as 500 L-1 over its neighboring land and tropical oceans. Given the same magnitude of precipitation, the spectrum of ice particle sizes is found to be wider over the TP than other regions. 展开更多
关键词 CloudSat/CALIPSO cloudmacrophysics cloudmicrophysics cloud verticalstructures PRECIPITATION Tibetan Plateau
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Seasonal dynamics of crustacean zooplankton community structure in Erhai Lake, a plateau lake, with reference to phytoplankton and environmental factors 被引量:9
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作者 杨威 邓道贵 +1 位作者 张赛 胡翠林 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第5期1074-1082,共9页
The seasonal dynamics of a crustacean zooplankton community in Erhai Lake was investigated from May 2010 to April 2011. In total, 11 species were recorded, including six(6 genera) cladoceran and five(5 genera) copepod... The seasonal dynamics of a crustacean zooplankton community in Erhai Lake was investigated from May 2010 to April 2011. In total, 11 species were recorded, including six(6 genera) cladoceran and five(5 genera) copepod species. The crustacean zooplankton densities ranged from 24.3 to 155.4 ind./L. In winter and spring, the large-bodied cladoceran Daphnia galeata dominated the crustacean plankton community. In summer and autumn, when the colonial or filamentous algae dominated the phytoplankton communities, the small-bodied species(e.g. B osmina fatalis, Ceriodaphnia quadrangular, and Mesocyclops leuckarti) replaced the large-bodied ones. One-way ANOVA and redundancy analysis revealed that community structure was dependent upon total nitrogen, total phosphorus, water temperature, transparency, and the biomass of small algae. The variation in both phytoplankton structure and environmental variables were important factors in the seasonal succession of crustacean zooplankton structure in Erhai Lake. 展开更多
关键词 Erhai Lake crustacean zooplankton community structure seasonal dynamics
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Micro-Pulse Lidar Measurements of Aerosol Vertical Structure over the Loess Plateau 被引量:27
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作者 HUANG Jian-Ping HUANG Zhong-Wei BI Jian-Rong ZHANG Wu ZHANG Lei 《Atmospheric and Oceanic Science Letters》 2008年第1期8-11,共4页
Knowledge of the vertical distribution of aerosols in the free troposphere is important for estimating their impact on climate. In this study, direct observations of the vertical distribution of aerosols in the free t... Knowledge of the vertical distribution of aerosols in the free troposphere is important for estimating their impact on climate. In this study, direct observations of the vertical distribution of aerosols in the free troposphere are made using surface Micro-Pulse Lidar (MPL) measurements. The MPL measurements were made at the Loess Plateau (35.95°N, 104.1°E), which is near the major dust source regions of the Taklimakan and Gobi deserts. The vertical distribution of the MPL backscattering suggested that nondust aerosols floated from ground level to an altitude of approximately 9 km around the source regions. Early morning hours are characterized by a shallow aerosol layer of a few hundred meters thick. As the day progresses, strong convective eddies transport the aero- sols vertically to more than 1500 m. 展开更多
关键词 LIDAR AEROSOL vertical structure Loess Plateau
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First principles study on electronic structure and optical properties of novel Na-hP4 high pressure phase 被引量:1
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作者 施毅敏 叶绍龙 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第6期1092-1096,共5页
The electronic structure and optical properties of novel Na-hP4 high pressure phase at different pressures(260,320,400 and 600 GPa)were investigated by the density functional theory(DFT)with the generalized gradient a... The electronic structure and optical properties of novel Na-hP4 high pressure phase at different pressures(260,320,400 and 600 GPa)were investigated by the density functional theory(DFT)with the generalized gradient approximation(GGA)for the exchange and correlation energy.The band structure along the higher symmetry axes in the Brillouin zone,the density of states(DOS) and the partial density of states(PDOS)were presented.The band gap increases and the energy band expands to some extent with the pressure increasing.The dielectric function,reflectivity,energy-loss function,optical absorption coefficient,optical conductivity, refractive index and extinction coefficient were calculated for discussing the optical properties of Na-hP4 high pressure phase at different pressures. 展开更多
关键词 first principles novel Na-hP4 phase high pressure phase density functional theory electronic structure optical properties
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The Characteristics of Turbulence Structure and Transfer over the Middle Area of the Tibetan Plateau
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作者 LI Fu-Yu LI Xiao-Lan ZHANG Hong-Sheng 《Atmospheric and Oceanic Science Letters》 CSCD 2013年第2期67-73,共7页
In this paper, turbulent data obtained from the Damxung site during the Secondary Tibetan Plateau Science Experiment (TIPEX) in 1998 are used to study the characteristics of the turbulent spectra, turbulence transport... In this paper, turbulent data obtained from the Damxung site during the Secondary Tibetan Plateau Science Experiment (TIPEX) in 1998 are used to study the characteristics of the turbulent spectra, turbulence transport, and the dissipation rates of turbulent kinetic energy, temperature variance, and humidity variance in the middle area of the Tibetan Plateau. The turbulent spectra of wind velocity, potential temperature, and humidity satisfy the-2/3 power law in the high frequency range. Horizontal transportation of heat and water vapor is negligible compared with vertical transportation under strong unstable conditions, and as the stability parameter z/L increases (where z is the observational height, and L is the Monin Obukhov length), horizontal transportation becomes dominant under near-neutral, neutral, and stable conditions. The non-dimensional temperature and humidity variances are 20% less than the temperature and humidity gradient variances. These deficits appear to increase as the absolute stability parameter increases. Moreover, the effects of turbulence transportation and pressure variance exist throughout the entire stability region. 展开更多
关键词 turbulence structure turbulence transfer dissipation rate observational method Tibetan Plateau
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An extended HLA multilayer federation integration architecture for multidisciplinary collaborative simulation
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作者 唐树才 《High Technology Letters》 EI CAS 2009年第4期429-433,共5页
The development of complex products is essentially concerned with multidisciplinary knowledge. Running on Internet, integration based on muhilayer federation architecture and dynamic reuse of simulation resources are ... The development of complex products is essentially concerned with multidisciplinary knowledge. Running on Internet, integration based on muhilayer federation architecture and dynamic reuse of simulation resources are the major difficulties for complex product collaborative design and simulation. Since the traditional Run-Time Infrastructure (RTI) is not good at supporting these new requirements, an extended high level architecture (HLA) multilayer federation integration architecture (MLFIA), based on the resource management federation (RMF) and its supporting environment based Service-oriented architecture (SOA) and HLA (SOHLA) are proposed, The idea and realization of two key technologies, the dynamic creation of simulation federation based on RMF, TH RTI, an extensible HLA runtime infrastructure (RTI), used at Internet are emphasized. Finally, an industry case about multiple unit (MU) is given. 展开更多
关键词 complex product SOA-Based HLA (SOHLA) multilayer federation integration architecture (MLFIA) multidisciplinary collaborative simulation resource management federation (RMF)
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Reasons for Charles de Gaulle Airport Collapse
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作者 Toomas Kaljas 《Journal of Civil Engineering and Architecture》 2017年第5期411-419,共9页
In the early morning hours of May 23, 2004, passengers in Terminal 2E at the Charles de Gaulle Airport in Paris partially collapsed resulting in several fatalities. Structural failure was caused by multiple reasons, a... In the early morning hours of May 23, 2004, passengers in Terminal 2E at the Charles de Gaulle Airport in Paris partially collapsed resulting in several fatalities. Structural failure was caused by multiple reasons, all contributing to failure. Similar structures have been successfully erected and built around the world. One famous and comparable structure is the Berlin Main Railway Station. After investigations, it becomes clear that Charles de Gaulle Airport lacks suitable and effective geometry, which is present in Berlin Railway Station. 展开更多
关键词 Charles de Gaulle airport collapse structural failure inadequate external reinforcement geometry.
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Evolution of terraces Ⅰ–Ⅲ along the Anning River, western Sichuan, based on pollen records and terrace structure 被引量:3
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作者 CHENG JianWu1,2 1 Institute of Geology, China Earthquake Administration, Beijing 100039, China 2 Earthquake Administration of Gansu Province, Lanzhou 730000, China 《Science China Earth Sciences》 SCIE EI CAS 2011年第1期127-135,共9页
This study reconstructs the long-term evolution of river terraces over large spatial scales along the Anning River, western Sichuan, and identifies external factors controlling terrace formation. Pollen record analysi... This study reconstructs the long-term evolution of river terraces over large spatial scales along the Anning River, western Sichuan, and identifies external factors controlling terrace formation. Pollen record analysis and terrace structure indicate that formation of the middle section of terraces I-III resulted from the interaction of changing climates and uplift of the margins of the Qinghai-Tibet Plateau. The relative influence of climate and uplift in terrace formation changes in different periods. The terraces reveal multiple, gradual uplift events on the eastern Qinghai-Tibet Plateau, which is of great significance for determining uplift mechanisms across the entire plateau. 展开更多
关键词 Anning River in western Sichuan terrace formation POLLEN PALEOCLIMATE
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Microstructure Evolution of Zr_(50)Cu_(18)Ni_(17)Al_(10)Ti_5 Bulk Metallic Glass during Cold-rolling 被引量:1
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作者 Honghong Yan Yong Hu +2 位作者 Zhijie Yan Xiaohua Zheng Yongtang Li 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2012年第8期756-760,共5页
Zr5018Nil1AlTi10Ti5 bulk metallic glass has been rolled at room temperature up to 95% in thickness reduction, and the dependence of microstructure on the strain was investigated. With increasing thickness reduction, t... Zr5018Nil1AlTi10Ti5 bulk metallic glass has been rolled at room temperature up to 95% in thickness reduction, and the dependence of microstructure on the strain was investigated. With increasing thickness reduction, the full width at half maximum (FWHM) and crystallization enthalpy decrease gradually till 80%, and then increase evidently at 95%. It is revealed that the reversible transition between the ordered and disordered atomic configurations was found in the metallic glass as the deformation proceeds, which is further verified by the high-resolution transmission electron microscopy images. The final microstructure in metallic glass during cold-rolling is the net result of two competing processes between shear-induced disordering and diffusion controlled reordering. 展开更多
关键词 Metallic glasses COLD-ROLLING MICROSTRUCTURE
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Crustal structure of northeastern margin of the Tibetan Plateau by receiver function inversion 被引量:22
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作者 LIU QiMin ZHAO JunMeng +1 位作者 LU Fang LIU HongBing 《Science China Earth Sciences》 SCIE EI CAS 2014年第4期741-750,共10页
Using seismic data of about one year recorded by 18 broadband stations of ASCENT project, we obtained 2547 receiver func- tions in the northeastern Tibetan Plateau. The Moho depths under 14 stations were calculated by... Using seismic data of about one year recorded by 18 broadband stations of ASCENT project, we obtained 2547 receiver func- tions in the northeastern Tibetan Plateau. The Moho depths under 14 stations were calculated by applying the H-x domain search algorithm. The Moho depths under the stations with lower signal-noise ratio (SNR) were estimated by the time delay of the PS conversion. Results show that the Moho depth varies in a range of -40--60 kin. The Moho near the Haiyuan fault is vague, and its depth is larger than those on its two sides. In the Qinling-Qilian Block, the Moho becomes shallower gradually from west to east. To the east of 105~E, the average depth of the Moho is 45 km, whereas the west is 50 km or even deeper. Combining our results with surface wave research, we suggest a boundary between the Qinling and the Qilian Mountains at around 105~E. S wave velocities beneath 15 stations have been obtained through a linear inversion by using Crust2.0 as an ini- tial model, and the crustal thickness that was derived by H-x domain search algorithm was also taken into account. The results are very similar to the results of previous active source studies. The resulting figure indicates that low velocity layers devel- oped in the middle and lower crust beneath the transition zone of the Tibet Block and western Qinling, which may be related to regional faults and deep earth dynamics. The velocity of the middle and lower crust increases from the Songpan Block to the northeastern margin of Tibetan Plateau. Based on the velocity of the crust, the distribution of the low velocity zone and the composition of the curst (Poisson's ratio), we infer that the crust thickening results from the crust shortening along the direc- tion of compression. 展开更多
关键词 northeastern margin of Tibetan Plateau receiver function crustal structure crust flow
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An investigation into the three-dimensional cloud structure over East Asia from the CALIPSO-GOCCP Data 被引量:5
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作者 YIN JinFang WANG DongHai +1 位作者 XU HuanBin ZHAI GuoQing 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第12期2236-2248,共13页
The spatial distribution of clouds and their seasonal variations, and the three-dimensional(3D) cloud structures over East Asia have been analyzed with the CALIPSO-GOCCP data during the period from 2007 to 2012. The r... The spatial distribution of clouds and their seasonal variations, and the three-dimensional(3D) cloud structures over East Asia have been analyzed with the CALIPSO-GOCCP data during the period from 2007 to 2012. The results show that there is a large cloud fraction greater than 0.7 over southern China, and the largest cloud fraction appears in southwest China. Besides, a large cloud fraction occurs over the southeast of the Tibetan Plateau. The total and high cloud fractions show notable variations with seasons, while the middle and low cloud fractions vary a little. As for cloud vertical structure, significant differences of the cloud vertical distributions are observed between over land and ocean. Cloud fractions and the height of the maximum cloud fractions decline gradually with the increasing latitude, except for the vertical-latitude profiles over the Tibetan Plateau regions. The longitude-vertical cross sections show similar patterns from the longitude 70° E to 140° E, except the profiles with large cloud fractions over the Tibetan Plateau. From the horizontal distribution patterns and vertical structures of the clouds over East Asia, it is concluded that the huge terrain of the Tibetan Plateau has significant impacts on the cloud formation over the Tibetan Plateau region and the areas to the east. At last, the clouds from the CALIPSO-GOCCP observations are compared to those from the ERA-Interim reanalysis data. The results indicate that the ERA-Interim reanalysis data provide reasonable spatial distribution patterns and the vertical structures in terms of the total cloud fraction over East Asia. However, the total cloud fraction was underestimated about 20% by the ERA-Interim reanalysis data over most parts of East Asia, especially over the neighboring areas east of the Tibetan Plateau. Additionally, the ERA-interim reanalysis data overestimate the cloud fractions at each level in the vertical direction. 展开更多
关键词 CALIPSO cloud fraction cloud three-dimension structure ERA-interim reanalysis data
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Crustal P-wave velocity structure in the northeastern margin of the Qinghai-Tibetan Plateau and insights into crustal deformation 被引量:2
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作者 Shuaijun WANG Baojin LIU +6 位作者 Xiaofeng TIAN Baofeng LIU Xianghui SONG Xiaoguo DENG Yinan SUN Cejun MA Yudong YANG 《Science China Earth Sciences》 SCIE EI CAS CSCD 2018年第9期1221-1237,共17页
The transitional area between the northeastern margin of the Qinghai-Tibetan Plateau, Ordos Block and Alxa Block, also being the northern segment of the North-South Seismic Belt, is characterized by considerably high ... The transitional area between the northeastern margin of the Qinghai-Tibetan Plateau, Ordos Block and Alxa Block, also being the northern segment of the North-South Seismic Belt, is characterized by considerably high seismicity level and high risk of strong earthquakes. In view of the special tectonic environment and deep tectonic setting in this area, this study used two seismic wide-angle reflection/refraction cross profiles for double constraining, so as to more reliably obtain the fine-scale velocity structure characteristics in both the shallow and deep crust of individual blocks and their boundaries in the study area, and further discuss the seismogenic environment in seismic zones with strong historical earthquakes. In this paper, the P-wave data from the two profiles are processed and interpreted, and two-dimensional crustal velocity structure models along the two profiles are constructed by travel time forward modeling. The results show that there are great differences in velocity structure, shape of intra-crustal interfaces and crustal thickness among different blocks sampled by the two seismic profiles. The crustal thickness along the Lanzhou-Huianbu-Yulin seismic sounding profile (L1) increases from -43 km in the western margin of Ordos Block to -56 km in the Qilian Block to the west. In the Ordos Block, the velocity contours vary gently, and the average velocity of the crust is about 6.30 km s^-1; On the other hand, the velocity structures in the crust of the Qilian Block and the arc-like tectonic zone vary dramatically, and the average crustal velocities in these areas are about 0.10 km s^-1 lower than that of the Ordos Block. In addition, discontinuous low-velocity bodies (LVZ1 and LVZ2) are identified in the crust of the Qilian Block and the arc-like tectonic zone, the velocity of which is 0.10-0.20 krn s^-1 lower than that of the surroundings. The average crustal thickness of the Ordos Block is consistently estimated to be around 43 km along both Profile L2 (Tongchuan-Huianbu-Alashan left banner seismic sounding profile) and Profile L1. In contrast to the gently varying intra-crustal interfaces and velocity contours in the Ordos Block along Profile L 1, which is a typical structure characteristic of stable cratons, the crustal structure in the Ordos Block along Profile L2 exhibits rather complex variations. This indicates the presence of significant structural differences in the crust within the Ordos Block. The crustal structure of the Helan Mountain Qilian Block and the Yinchuan Basin is featured by "uplift and depression" undulations, showing the characteristics of localized compressional deformation. Moreover, there are low-velocity zones with altemative high and low velocities in the middle and lower crust beneath the Helan Mountain, where the velocity is about 0.15-0.25 km s^-1 lower than that of the surrounding areas. The crustal thickness of the Alxa Block is about 49 kin, and the velocity contours in the upper and middle-lower crust of the block vary significantly. The complex crustal velocity structure images along the two seismic sounding profiles L1 and L2 reveal considerable structural differences among different tectonic blocks, their coupling relationships and velocity structural features in the seismic zones where strong historical earthquakes occurred. The imaging result of this study provides fine-scale crustal structure information for further understanding the seismogenic environment and mechanism in the study area. 展开更多
关键词 Northeastern margin of the Qinghai-Tibetan Plateau The Ordos Block Crustal velocity structure Deep seismicsounding
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Scanning Tunneling Microscope Observations of Non-AB Stacking of Graphene on Ni Films 被引量:1
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作者 Ruiqi Zhao Yanfeng Zhang +4 位作者 Teng Gao Yabo Gao Nan Liu Lei Fu Zhongfan Liu 《Nano Research》 SCIE EI CAS CSCD 2011年第7期712-721,共10页
Microscopic features of graphene segregated on Ni films prior to chemical transfer--including atomic structures of monolayers and bilayers, Moire patterns due to non-AB stacking, as well as wrinkles and ripples caused... Microscopic features of graphene segregated on Ni films prior to chemical transfer--including atomic structures of monolayers and bilayers, Moire patterns due to non-AB stacking, as well as wrinkles and ripples caused by strain effects-have been characterized in detail by high-resolution scanning tunneling microscopy (STM). We found that the stacking geometry of the bilayer graphene usually deviates from the traditional Bernal stacking (or so-called AB stacking), resulting in the formation of a variety of Moir6 patterns. The relative rotations inside the bilayer were then qualitatively deduced from the relationship between Moir6 patterns and carbon lattices. Moreover, we found that typical defects such as wrinkles and ripples tend to evolve around multi-step boundaries of Ni, thus reflecting strong perturbations from substrate corrugations. These investigations of the morphology and the mechanism of formation of wrinkles and ripples are fundamental topics in graphene research. This work is expected to contribute to the exploration of electronic and transport properties of wrinkles and ripples. 展开更多
关键词 GRAPHENE scanning tunneling microscopy (STM) SEGREGATION Moire pattern growth
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