检索结果-南通市图书馆

Oxfordian (Jurassic) mayaitid (ammonite) dispersal in the Tibetan Himalaya as the first signal of the establishment of the Indo-Austrai subrealm

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2003年第4期13卷 44-49页

作者： yin jiarun(China University of Geosciences, Beijing 100083, China) China Univ Geosci Beijing 100083 Peoples R China

New fossil collections in the Lanongla area, Tibetan Himalaya enables the establishment of the Upper Jurassic ammonoidsuccession. Middle Oxfordian ammonite-fauna is characterized by endemic epimayaittds with a marine deepening event, suggesling a high stand of sea Ievel in the Tibetan Himalaya. Distribution of mayaitids around the Eastern Gondwana can be regarded as the first signal of the Indo-AustraI Subrealm that was progressively established during the Late Jurassic and Early Cretaceous times.

关键词： Jurassic Oxfordian ammonites Tibetan Himalaya Indo-Austral Subrealm.

Lower Jurassic Sequence Stratigraphy and Sedimentary Facies on the North Slope of Mount Qomolangma

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 1996年第3期70卷 303-316,331页

作者： Shi Xiaoying, Lei Zhenyu and yin jiarun China University of Geosciences, Beijing

The Lower Jurassic is subdivided in ascending order into the Wulong, Kangdui and Yongjia Formations on the north slope of Mount Qomolangma, with a total thickness of 1362 m. They are thought to have been deposited respectively in the environments of the carbonate ramp fault-bounded basins and carbonate platform, with six sedimentary facies and six sub-facies. During the Early Jurassic, the Qomolangma area experienced strong faulting and subsidence, and was of a matured rift basin. The Lower Jurassic consists of eleven 3rd-order sequences, which can be grouped into three 2nd-order sequences and form a large transgressive-regressive cycle. The 3rd-order sequences and the corresponding sea-level changes recognized in the area can be correlated quite well with those set up in the western Tethys, and may have been caused by the eustatic fluctuations, while the 2nd-order sequences seem to be more closely related to the basement subsidence and the variation in sedimentary influx, indicating the evolution of the eastern Neotethys and the movement of the plates on its two sides.

关键词： Lower Jurassic sedimentary facies sequence stratigraphy sea-level changes southern Tibet

An　Outline　of　Mesozoic　to　Paleogene　SequenceStratigraphy　and　Sea－Level　Changes　in　Northern　Himalayas，Southern　Xizang

在线全文

学校读者我要写书评

暂无评论

Journal of Earth Science 1995年第1期14卷 16-40页

作者： Shi Xiaoying yin jiarun(Department of Geology and Mineral Resources, China University of Geosciences,Beijing 100083)

In the Northern Himalayan region of Southern Xizang (Tibet),from the Lower Triassic to Upper Eocene 73 Sequences have been identified, with an average duration of 2.9 Ma;these can in turn be grouped into 24 super-Sequences and 6 super-sequence sets. During Mesozoic and Paleogene, several large sea - level falls occurred in the Eastern Neo-Tethys. Among the recognized sea- level falls, the important ones include those at the ages of 255 Ma, 215 Ma,177 Ma, 138 Ma, 103 Ma and 68 Ma .Those at 239 Ma, 215 Ma, 157 Ma,80 Ma, 50Ma and 36 Ma are also significant. The third-order Sequences and sea-level cycles Probably reflect mainly global sea - level fluctuations, while the higher rank cycles seem more closely related to the basin evolution of the Neo-Tethys. Based on the study, six major periods have been suggested for ths tectonic evolution of the Eastern Neo-Tethys and the plates, i. e. the Pangea Period (Pre-Triassic), continental rifting Period (Triassic to Early Jurassic ), inter-continental sea Period (Middle Jurassic ), continental divergence period (late Middle Jurassic to Early Cretaceous ), continental convergence period (Late Cretaceous ) and the continental collision Period (Paleogene ). These major Periods can be further subdivided into eight stages according to the basin evolution. In each of the periods and Stages, Sequences and their boundaries show clear characters related to the tectonic background. The study indicater that the initial breakup of the Pangea along the Indus- Yarlung may have taken Place around 239 Ma. The Late Bathonian to Early Callovian seems to have been a critical time in the evolution of the Neo-Tethys, with the turning Point around 158 Ma. The blocks split from the northern margin of the Gondwana continual did not obviously drift away from the Indian Plate until Callovian .The oceanic crust subduction in the Neo- Tethys may have Started at 113Ma, while the contraction of the ocean probably began at 107- 103 Ma. The initial contact of

关键词： Sequence stratigraphy sea-level change Mesozoic Cenozoic Northern Himalayas,southern Xizang.

西藏喜马拉雅瑞替阶和赫塘阶菊石组合及其生物年代学对比

在线全文

学校读者我要写书评

暂无评论

地质学报 2005年第5期79卷 577-586页

作者：阴家润中国地质大学北京100083

基于西藏聂拉木拉弄拉地区的格米格剖面新近逐层采集的菊石及缝合线研究,已识别出晚三叠世瑞替阶Choristoceras marshi组合,过渡带Neophyllites-Choristoceras组合,下赫塘阶Psiloceras calliphyllum组合和中赫塘阶Discamphiceras pleuronotum组合。作为东特提斯唯一的三叠系-侏罗系界线地层剖面,格米格菊石组合序列提供了特提斯范围内三叠/侏罗系界线菊石组合(或菊石带)以及地层对比的基础:Choristoceras marshi组合可以和欧洲,南美的秘鲁和智利的MARSHI菊石带,北美的内瓦达,不列颠哥伦比亚(加拿大)等地CRICKMAYI菊石带比较。Neophyllites-Choristoceras组合可和北美的内瓦达侏罗系底部TILMANNI菊石带Neophyllites和Choristoceras共生动物群比较。Psiloceras calliphyllum组合能够和北阿尔卑斯地区CALLIPHYLLUM菊石带比较, 证明北阿尔卑斯地区三叠系和侏罗系之间存在地层缺失。

关键词：西藏喜马拉雅地区三叠系/侏罗系界线菊石组合菊石喜马拉雅西藏年代学阿尔卑斯地区不列颠哥伦比亚生物

东特提斯喜玛拉雅侏罗纪菊石年代地层学研究新进展

在线全文

学校读者我要写书评

暂无评论

现代地质 2000年第3期14卷 342-347页

作者：阴家润夏遵义中国地质大学地球科学与资源学院北京100083

西藏南部拉弄拉地区的侏罗纪菊石资料研究表明 ,该地有特提斯喜玛拉雅地区最完整的侏罗纪菊石层序 ,据此可与西北欧标准菊石带以及其他地区菊石层序对比。

关键词：侏罗纪菊石年代地层学东特提斯喜玛拉雅地区

唐古拉山侏罗系沉积的若干特征及沉积盆地背景条件的探讨

在线全文

学校读者我要写书评

暂无评论

现代地质 1989年第2期3卷 155-164页

作者：阴家润

对于唐古拉山侏罗系沉积类型的不同认识由来已久,然而无论是将其视为地槽型沉积,还是地台型沉积,均难以令人满意地解释该区侏罗纪沉积的特点和性质。作者在野外工作和室内研究的基础上,从地球化学因素、古生态分析、沉积岩沉积构造和... 详细信息

对于唐古拉山侏罗系沉积类型的不同认识由来已久,然而无论是将其视为地槽型沉积,还是地台型沉积,均难以令人满意地解释该区侏罗纪沉积的特点和性质。作者在野外工作和室内研究的基础上,从地球化学因素、古生态分析、沉积岩沉积构造和矿物结构成熟度等综合考虑,对该区侏罗纪沉积的特点和性质提出下列证据: (1)含盐度值一般均低于广海的平均盐度值。 (2)发育了海相一半咸水相一陆相的双壳类动物群序列,并以半咸水双壳类属占优势。 (3)沉积构造多为浅水成因的小型波痕,交错层理沉积组合。 (4)沉积岩粒度分析表现了近岸环境的概率曲线特征。 (5)沉积岩矿物结构,成熟度较高,未见海相成因的粒级层理。结论是唐古拉山区侏罗系应为近岸局限海环境下的沉积产物,在海退时期还发育了滨岸湖相沉积。根据羌塘地区侏罗纪沉积相空间展布的特点,可以认为唐古拉山区侏罗系仅仅是大西洋型大陆边缘沉积的一个组成部分,是陆架大幅度坳陷所承受的巨厚陆源碎屑沉积,整个羌塘地区侏罗纪沉积在空间上的演替关系及其巨大厚度可借助于大西洋型大陆边缘特有的大陆堤前展沉积模式得到较好的解释。

关键词：唐古拉山侏罗系沉积特征大陆堤双壳类生物组合含盐度

MDTCNet:Multi-Task Classifications Network and TCNN for Direction of Arrival Estimation

在线全文

学校读者我要写书评

暂无评论

China Communications 2024年第10期 148-166页

作者： Yu jiarun Wang Yafeng Department of Information and Communication Engineering Beijing University of Posts and Telecommunications Key Laboratory of Universal Wireless Communications (Ministry of Education) Beijing University of Posts and Telecommunications

The direction-of-arrival(DoA) estimation is one of the hot research areas in signal processing. To overcome the DoA estimation challenge without the prior information about signal sources number and multipath number in millimeter wave system,the multi-task deep residual shrinkage network(MTDRSN) and transfer learning-based convolutional neural network(TCNN), namely MDTCNet, are proposed. The sampling covariance matrix based on the received signal is used as the input to the proposed network. A DRSN-based multi-task classifications model is first introduced to estimate signal sources number and multipath number simultaneously. Then, the DoAs with multi-signal and multipath are estimated by the regression model. The proposed CNN is applied for DoAs estimation with the predicted number of signal sources and paths. Furthermore, the modelbased transfer learning is also introduced into the regression model. The TCNN inherits the partial network parameters of the already formed optimization model obtained by the CNN. A series of experimental results show that the MDTCNet-based DoAs estimation method can accurately predict the signal sources number and multipath number under a range of signal-to-noise ratios. Remarkably, the proposed method achieves the lower root mean square error compared with some existing deep learning-based and traditional methods.

关键词：

Defect engineering in transition-metal(Fe,Co,andNi)-based electrocatalysts for water splitting

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Carbon Energy 2024年第6期6卷 165-199页

作者： Kaili Wu Chaojie Lyu jiarun Cheng Weifan Ding Jiwen Wu Qian Wang Woon-Ming Lau Jinlong Zheng Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijingChina School of Chemistry and Chemical Engineering Linyi UniversityLinyiChina Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijingChina Shunde Innovation School University of Science and Technology BeijingFoshanChina

Electrocatalytic water splitting seems to be an efficient strategy to deal with increasingly serious environmental problems and energy crises but still suffers from the lack of stable and efficient *** practical electrocatalysts by introducing defect engineering,such as hybrid structure,surface vacancies,functional modification,and structural distortions,is proven to be a dependable solution for fabricating electrocatalysts with high catalytic activities,robust stability,and good *** review is an overview of some relevant reports about the effects of defect engineering on the electrocatalytic water splitting performance of *** detail,the types of defects,the preparation and characterization methods,and catalytic performances of electrocatalysts are presented,emphasizing the effects of the introduced defects on the electronic structures of electrocatalysts and the optimization of the intermediates'adsorption energy throughout the ***,the existing challenges and personal perspectives of possible strategies for enhancing the catalytic performances of electrocatalysts are *** in-depth understanding of the effects of defect engineering on the catalytic performance of electrocatalysts will light the way to design high-efficiency electrocatalysts for water splitting and other possible applications.

关键词： defect engineering electrocatalytic water splitting element doping interfacial engineering vacancy

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

唐古拉山北坡侏罗纪双壳类化石新材料

现代地质 1987年第Z1期 327-337页

作者：阴家润

唐古拉山地区侏罗系发育良好,是国内侏罗纪双壳类最丰富的地区之一。本文描述其中的8属17种,大多数为国内首次报道的种。由于唐古拉山地区在侏罗纪时正好位于东亚分区(East Asian province)、埃塞俄比亚分区(Ethiopian province)和欧洲... 详细信息

唐古拉山地区侏罗系发育良好,是国内侏罗纪双壳类最丰富的地区之一。本文描述其中的8属17种,大多数为国内首次报道的种。由于唐古拉山地区在侏罗纪时正好位于东亚分区(East Asian province)、埃塞俄比亚分区(Ethiopian province)和欧洲分区(European province)3个不同的双壳类生物地理分区接合处,因此本区双壳类显示出一定的混生色彩,具有上述各区的一些特征属或种。但是更值得注意的是自唐古拉山向东南方向,包括西藏东部、云南、缅甸及泰国的侏罗系中,双壳类动物群含有大量的共同分子,并形成特殊的地方性生物群,考虑到侏罗纪古板块的构造格局,对上述特提斯北岸东缘进行进一步研究,将有助于建立侏罗纪的一个新的双壳类生物地理分区。

关键词：层位产地雁石坪左壳登记号放射脊北坡双壳类动物唐古拉山当拉山韧带窝牛津阶巴通阶图版壳饰侏罗系化石