检索结果-南通市图书馆

Journal of Palaeogeography 2014年第3期3卷 323-330页

作者： ye-ming cheng Yu-Fei Wang cheng-Sen Li The Geological Museum of China State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences

The Upper Miocene Xiaohe Formation of the Yuanmou Basin in Yunnan Pro- vince, southwestern China, is famous for its hominoid fauna and is important for studying the Late Cenozoic human and mammal evolution. Abundant fossil wood was found associated with this fauna, which provided important evidence for palaeoenvironmental reconstruction of the basin. Among the fossil wood, two different taxa have been identified namely, Quercoxylon sp. （Fagaceae） and Pterocarya sp. （Juglandaceae）. Based on the habitats of their Nearest Living Relatives （NRLs）, it is suggested that upland subtropical evergreen broad-leaved forest dominated by QuercuslLithocarpus was common around the basin, while a lowland deciduous broad-leaved forest dominated by Pterocarya was present on the river bank of the basin during the Late Miocene.

关键词： fossil wood Quercoxylon Pterocarya palaeovegetation Late Miocene,Yuanmou Basin

GIS-based spatial prediction of landslide using road factors and random forest for Sichuan-Tibet Highway

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2022年第2期19卷 461-476页

作者： ye cheng-ming WEI Rui-long GE Yong-gang LI Yao Jose Marcato JUNIOR Jonathan LI Key Laboratory of Earth Exploration and Information Technology of Ministry of Education Chengdu University of TechnologyChengdu 610059China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China Faculty of Engineering Architecture and Urbanism and GeographyFederal University of Mato Grosso do SulCampo Grande 79070-900Brazil Department of Geography and Environmental Management University of WaterlooWaterlooONN2L 3G1Canada

Accurate evaluation of landslide susceptibility is very important to ensure the safe operation of mountain *** Sichuan-Tibet Highway,which traverses the east of the Tibetan Plateau,frequently encounters natural *** studies generally use statistical methods to analyze the hazards along the Sichuan-Tibet *** this research,we present two road factors,namely aspect to road and road profile to increase the accuracy of landslide susceptibility mapping by considering the influence of landslide movement direction on ***,the aspect to road,which represents the impact of different landslide movement directions on the highway,was extracted by combining road direction with mountain ***,the road profile,which reflects the subgrade structure between the road and surrounding mountains,was extracted according to the terrain ***,the landslide susceptibility maps were produced based on the random forest(RF)method by using 473 landslides and 10 conditioning factors,including road factors(aspect to road,road profile)and primitive factors(slope,aspect,curvature,relief amplitude,peak ground acceleration,crustal movement velocity,faults,rainfall).The area under the receiver operating characteristic curve(AUC)and the Gini importance were used to evaluate the performance of proposed road *** AUC values on two groups that add road factors and only use primitive factors were 0.8517 and 0.8243,*** Gini importance indicated that road profile(0.123)and aspect to road(0.116)have a significant contribution to landslides compared with the primitive *** results of multi-collinearity analysis and frequency ratio confirmed the suitability of the road factors for predicting hazards along the highway.

关键词： Landslide susceptibility Spatial modeling Random forest Sichuan-Tibet Highway

GiT-based structural geologic feature analysis of the southern segment of Longmenshan fault zone for earthquake evidence

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2016年第5期13卷 906-916页

作者： ye cheng-ming CUI Peng Saied PIRASTEH Jonathan LI MENG Qingkai BI Xiao-jia ZHANG Jian-qiang Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China Key Lab.of Earth Exploration and Information Technology of Ministry of Education Chengdu University of TechnologyChengdu 610059China Department of Geography and Environmental Management Faculty of EnvironmentUniversity of WaterlooWaterlooOntarioCanada N2L 3G1Canada chengdu Earthquake Mitigation Bureau Chengdu 610042China

The Longmenshan fault is a thrust fault which runs along the base of the Longmen Mountains in Siehuan province, southwestern China. The southern segment of the fault had two distinct responses to the Ms 8 Wenehuan and Ms 7 Lushan earthquakes. This study determines characteristics of the structural geology of the Longmenshan fault to evaluate how it influenced the two aforementioned earthquakes. This research was done within a Geo- information Technologies （GiT） environment based on multi-source remote sensing and crustal movement data extracted from the Global Positioning System （GPS）. The spatial distribution of the southern segment of the Longmenshan fault zone was comprehensively analyzed to study both earthquakes. The study revealed that the Wenehuan and Lushan earthquakes occurred on two relatively independent faults. In addition, there was a nearly constant-velocity crustal movement zone between the two epicenters that probably had a compressive stress with slow motion. Furthermore, the central fault and a mountain back fault gradually merged from north to south. The Lushan earthquake of the Wenchuan earthquake. was not an affershock The research showed that fault zones within 30-50 km of State Highway 318 are intensive and complex. In addition, crustal movement velocity decreased rapidly, with a strong multi-directional shear zone. Thus, activity in that zone was likely stronger than in the northern part over the medium to long term.

关键词： Longmenshan fault zone Geoinformation Technologies (GiT) Remote Sensing (RS) Earthquake Crustal movement

Three-dimensional fracture of UO2 ceramic pellets by phase field modeling

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 169-180页

作者： Wei Xiong Xuan ye Hongzhang cheng Xiaoming Liu Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy Technology Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education Tsinghua University State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences School of Engineering Science University of Chinese Academy of Sciences

Fracture is the primary failure type for the UO2ceramic pellets,which are operated under irradiation and thermal processes,and physically confined by the *** this work,by combining closely coupled physical processes of heat conduction,heat transfer,and mechanical deformation with the cohesive phase field framework,we proposed a high-precision modeling of quasistatic cracking of three-dimensional （3D） UO2ceramic fuel pellets under high temperature and *** simulation results agree well with the experimental results,indicating that the proposed method has the potential to capture 3D crack modes in the interested time ***,we studied the relation of the 3D fracture patterns of fuel pellets with the peak power *** was found that the power level plays a critical role in determining the competition between radial and circumferential cracks,as well as transverse penetrating cracks.

关键词： phase field method nuclear fuel pellet coupled thermo-mechanical model thermal fracture

STUDY ON THE SECOND HARMONIC GENERATION OF SOME LANTHANIDE(Ⅲ) COORDINATION COMPOUNDS

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 1992年第2期3卷 135-136页

作者： Jia Fu WANG~*, Meng Hui CAI, cheng ye, Zhi ming FENG Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080

The measurements of second harmonic generation efficiencies of some coordination compounds of lanthanide(Ⅲ) carboxylates and β-diketonates have been reported. The results show thatmost of lanthanide cinnamate have S... 详细信息

关键词： SHG than COORDINATION COMPOUNDS STUDY ON THE SECOND HARMONIC GENERATION OF SOME LANTHANIDE

创伤性膝关节积脂血症X线及CT诊断的临床观察

在线全文

学校读者我要写书评

暂无评论

中国骨伤 2010年第6期23卷 412-413页

作者：叶明埕洞头县人民医院CT室浙江洞头325700

创伤性关节积脂血症（traumaticlipohemarthrosis,TLH）是指关节创伤后关节囊内形成脂-血平面,多继发关节内骨折,可发生于全身任何关节,以膝关节最常见。临床上约15%关节囊内骨折不能在X线片上发现,即为隐匿性骨折,而TLH与关节囊内骨折... 详细信息

创伤性关节积脂血症（traumaticlipohemarthrosis,TLH）是指关节创伤后关节囊内形成脂-血平面,多继发关节内骨折,可发生于全身任何关节,以膝关节最常见。临床上约15%关节囊内骨折不能在X线片上发现,即为隐匿性骨折,而TLH与关节囊内骨折有密切相关。分析2006年8月至2009年10月51例膝关节创伤性关节积脂血症X线、CT及临床完整资料，

关键词：膝关节创伤和损伤体层摄影,X线计算机诊断

在线全文

学校读者我要写书评

暂无评论

中国首次发现白垩纪桫椤科茎干化石

地球学报 2017年第2期38卷 135-143页

作者：程业明刘风香中国地质博物馆北京100034

松辽盆地是我国白垩系分布最广、厚度最大、发育最全的陆相沉积盆地。孢粉分析发现桫椤孢在松辽盆地白垩系中比较常见。但由于桫椤孢与桫椤科或者蚌壳蕨科具有亲缘关系。桫椤孢在地层中的发现不能明确表明桫椤科植物的存在。这种状况影... 详细信息

松辽盆地是我国白垩系分布最广、厚度最大、发育最全的陆相沉积盆地。孢粉分析发现桫椤孢在松辽盆地白垩系中比较常见。但由于桫椤孢与桫椤科或者蚌壳蕨科具有亲缘关系。桫椤孢在地层中的发现不能明确表明桫椤科植物的存在。这种状况影响了我们对松辽盆地古环境和古气候的精确分析。白垩纪桫椤科矿化茎干化石在黑龙江省齐齐哈尔市克山县的发现为解决桫椤科植物在松辽盆地存在与否的难题提供了重要证据。该化石为桫椤科树蕨植物的茎干片段,包括髓、网状中柱、皮层。分体中柱的横截面呈U、W或S形,外围具有厚壁组织鞘,分体中柱末端朝向髓部或者皮层。髓和皮层由薄壁组织组成,其中分布有许多维管束和根。创伤组织在髓中常见。当前化石是我国第一个桫椤科茎干化石记录。它的发现表明白垩纪时期松辽盆地北部曾经分布着现今多生长于热带、亚热带的桫椤科树蕨祖先类群。结合与其伴生的一些登普斯基树蕨、本内苏铁茎干等化石证据,可能指示当时气候为热带或者亚热带。

关键词：桫椤科树蕨茎干解剖结构桫椤孢白垩系黑龙江

在线全文

学校读者我要写书评

暂无评论

天津市水环境在线监测监控系统的建设

中国给水排水 2011年第20期27卷 36-38页

作者：李青叶承明天津市排水公司天津300012 国家城市排水监测网天津监测站天津300381

2011年天津市实施了清水工程,取得了显著成果,为了巩固治理成果投资建设了水环境在线监测监控系统。分析了监测点及监测项目的选择原则,介绍了该监控系统的总体设计。水环境在线监测监控系统的建立,能够显著提高水质监控技术的自动化、... 详细信息

2011年天津市实施了清水工程,取得了显著成果,为了巩固治理成果投资建设了水环境在线监测监控系统。分析了监测点及监测项目的选择原则,介绍了该监控系统的总体设计。水环境在线监测监控系统的建立,能够显著提高水质监控技术的自动化、现代化管理水平,实时掌握主要区域重点河道水体断面、污水处理厂进出水、排水管网的水质状况,预报、预警重大或区域性水质污染事故,区分不同行政管辖区域的水污染事故责任,核定COD、NH_3 -N等减排指标,从而提高涉水事故的快速反应能力,提高监控技术,为水资源、水环境监督管理提供科学依据。

关键词：水环境在线监测监控系统

中国云南元谋上新世千屈菜科紫薇木属一新种(英文)

在线全文

学校读者我要写书评

暂无评论

植物分类学报 2007年第3期45卷 315-320页

作者：程业明李承森姜笑梅王宇飞系统与进化植物学国家重点实验室中国科学院植物研究所中国林业科学研究院木材工业研究所北京100091

报道了来自中国云南元谋新华土林上新世地层的木化石新种——元谋紫薇Lagerstroemioxylon yuanmouensis ***,***,*** & ***。目前紫薇属Lagerstroemia分布于亚洲至澳大利亚北部的热带森林中,其中有一些种在我国的西南部和台湾省也有分... 详细信息

报道了来自中国云南元谋新华土林上新世地层的木化石新种——元谋紫薇Lagerstroemioxylon yuanmouensis ***,***,*** & ***。目前紫薇属Lagerstroemia分布于亚洲至澳大利亚北部的热带森林中,其中有一些种在我国的西南部和台湾省也有分布。在印度、缅甸、印度尼西亚和德国的第三纪地层中曾报道有紫薇属木化石的存在,这表明该属在第三纪分布的范围比现代更广。

关键词：生物地理紫薇属紫薇木属千屈菜科上新世云南中国

SECOND ORDER NONLINEAR OPTICAL PROPERTIES OF DICYANOPYRAZINES

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 1991年第10期2卷 765-768页

作者： cheng ye Zhi ming FENG Yah Jun CHEN Jia Fu WANG Hai Ou DONG (Institute of Chemistry, Academia Sinica, Beijing 100080) Dept. of Chemistry, Branch Campus of Peking University.

Second order nonlinear optical active 2,3-dichloro-5,6-dicyanopyrazine (DCDCP) and its monoamine-substituted derivatives had been synthesized. Their facile synthesis, high melt point, high incidence af substantial SHG activity and increased transparency inthe blue and near infrared make this class compounds appealling for further investigation.

关键词： SHG SECOND ORDER NONLINEAR OPTICAL PROPERTIES OF DICYANOPYRAZINES NLO