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土根曼苏砂岩铜矿新认识 被引量:4
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作者 王战华 赵祖应 +1 位作者 孔令芝 刘秀德 《新疆有色金属》 2003年第S1期12-15,共4页
土根曼苏砂岩铜矿床发育于北昆仑晚古生代陆缘裂谷拗陷盆地中,含矿岩系为一套浅海-滨海相碎屑岩-碳酸岩盐系,矿体赋存于紫红色碎屑岩系浅色岩层中,受一定层位制约。矿石中伴生有益组分为银。在相似层位中普遍发育铜矿化,表明这一地区具... 土根曼苏砂岩铜矿床发育于北昆仑晚古生代陆缘裂谷拗陷盆地中,含矿岩系为一套浅海-滨海相碎屑岩-碳酸岩盐系,矿体赋存于紫红色碎屑岩系浅色岩层中,受一定层位制约。矿石中伴生有益组分为银。在相似层位中普遍发育铜矿化,表明这一地区具有形成中-大型砂岩型铜矿的资源潜力。 展开更多
关键词 北昆仑 晚古生代 陆线裂谷拗陷盆地 土根曼苏 碎屑岩系 砂岩铜矿
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外商侵占中国电报利权与洋务派的政策 被引量:3
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作者 徐元基 《中国社会经济史研究》 1984年第2期90-103,共14页
欧美对电信技术经过几十年的试验改进,到十九世纪五六十年代,电报事业发展迅速,线路密布,在经济、政治、外交、军事各方面起着重要的作用。这种崭新的通讯工具,为资本主义列强统治并剥削殖民地和半殖民地国家提供了一项有力武器。随着... 欧美对电信技术经过几十年的试验改进,到十九世纪五六十年代,电报事业发展迅速,线路密布,在经济、政治、外交、军事各方面起着重要的作用。这种崭新的通讯工具,为资本主义列强统治并剥削殖民地和半殖民地国家提供了一项有力武器。随着电报线由西向东的渐渐扩展,随着同治四年(一八六五)太平天国起义被镇压后列强在华各口商务的急剧增长,外人在中国设立电线的交涉突出地提到议事日程上来。“查电线之设,洋人蓄志已久。其意倡于俄,而英、法继之,一国扬其波,众国遂随其流。”到甲午中日战争前,资本主义列强侵占中国电报利权的活动,大体上经历三个阶段:一, 展开更多
关键词 电线 陆线 电报 同治 李鸿章 盛宣怀 威妥玛 洋务派 载电线 照会
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Effects on Agronomic Traits of M_1 by Pollen of Upland Cotton Irradiated by ^(60)Co-γ Ray 被引量:2
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作者 岳洁瑜 唐灿明 《Agricultural Science & Technology》 CAS 2012年第3期525-528,532,共5页
[Objective] The aim was to provide reference for research on radiation and breeding of cotton pollen through irradiating common ripe pollen grain of upland cotton by 60Co-γ Ray of varied doses. [Method] Ripe pollen g... [Objective] The aim was to provide reference for research on radiation and breeding of cotton pollen through irradiating common ripe pollen grain of upland cotton by 60Co-γ Ray of varied doses. [Method] Ripe pollen grains of upland cotton were irradiated by 60Co-γ Ray with doses of 5, 10, 15, and 20 Gy, respectively, to learn radiation effect and select appropriate dose. [Result] Most properties of M1 obviously showed variation when dose was over 10 Gy; vitality, growth, and fertility were greatly inhibited when dose was 15 Gy which was almost semi-lethal concentration, and variation species were richest at the same time, which provided materi- als for practical breeding. [Conclusion] 60Co-γ Ray of 15 Gy is more suitable for mutagenesis research on ripe pollen grains of upland cotton. 展开更多
关键词 Upland cotton 60Co-γ Ray Irradiation Agronomic traits Genetic variation
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Highly nonlinear internal solitary waves over the continental shelf of the northwestern South China Sea 被引量:11
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作者 徐振华 尹宝树 侯一筠 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第5期1049-1054,共6页
Large amplitude internal solitary waves(ISWs) often exhibit highly nonlinear effects and may contribute significantly to mixing and energy transporting in the ocean.We observed highly nonlinear ISWs over the continent... Large amplitude internal solitary waves(ISWs) often exhibit highly nonlinear effects and may contribute significantly to mixing and energy transporting in the ocean.We observed highly nonlinear ISWs over the continental shelf of the northwestern South China Sea(19°35'N,112°E) in May 2005 during the Wenchang Internal Wave Experiment using in-situ time series data from an array of temperature and salinity sensors,and an acoustic Doppler current profiler(ADCP).We summarized the characteristics of the ISWs and compared them with those of existing internal wave theories.Particular attention has been paid to characterizing solitons in terms of the relationship between shape and amplitude-width.Comparison between theoretical prediction and observation results shows that the high nonlinearity of these waves is better represented by the second-order extended Korteweg-de Vries(KdV) theory than the first-order KdV model.These results indicate that the northwestern South China Sea(SCS) is rich in highly nonlinear ISWs that are an indispensable part of the energy budget of the internal waves in the northern South China Sea. 展开更多
关键词 internal solitary wave high nonlinearity South China Sea (SCS)
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BEACON SYNCHRONIZATION TECHNOLOGY FOR “BEIDOU” TERRESTRIAL IMPROVEMENT SYSTEM 被引量:2
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作者 WEIJin-chen TANGJi-qiang SHENFeng 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2005年第2期177-182,共6页
Synchronization is an essential technology in the radio navigation system. The technique for improving the “Beidou” positioning ability is presented through constituting the terrestrial improvement system, and the b... Synchronization is an essential technology in the radio navigation system. The technique for improving the “Beidou” positioning ability is presented through constituting the terrestrial improvement system, and the beacon synchronization of the improvement system with the “Beidou” one-way time transfer model is realized.The direct digital synthesis (DDS) is adopted to generate the pseudo-random code clock having high precision and stability. Meanwhile, the CPLD device is used to design the synchronization pulse picking-up module, the spread spectrum PN code generator and the spread spectrum modulator. Measurement results indicate that the beacon synchronization has the high precision and the stability. 展开更多
关键词 radio navigation system terrestrial improvement system time transfer SYNCHRONIZATION
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INFLUENCE OF SERIES OF SQUARE GRIDS ON FRACTAL DIMENSIONS-A Case Study of Mountains of China's Mainland 被引量:1
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作者 ZHUXiao-hua CAIYun-long 《Chinese Geographical Science》 SCIE CSCD 2004年第1期9-14,共6页
MANDELBROT enunciated the uncertainty of the length of a coastline in his paper "How long is the coastline of Britain?" published in Science in 1967. The fractal concept was presented for the first time in t... MANDELBROT enunciated the uncertainty of the length of a coastline in his paper "How long is the coastline of Britain?" published in Science in 1967. The fractal concept was presented for the first time in that paper and has been applied to many fields ever since. Although fractal dimensions of lots of phenomena were calculated by the box-counting method,the quantitative influence of series of square grids on them is ignored. The issue is systematically discussed as a case study of the mountains of China′s Mainland in this paper. And some significant conclusions are drawn as follows: 1) Although the fractal character objectively exists in the mountains of China′s Mainland,and it does not vary with the changes of series of square grids,the fractal dimensions of the mountains of China′s Mainland are different with these changes. 2) The fractal dimensions of the mountains of China′s Mainland vary with the average lengths of sides of series of square grids. The fractal dimension of the mountains of China′s Mainland is the function of the average length of side of square grid. They conform to the formula D=f(r) (where D is the fractal dimension,and r is the average length of side of square grid). 3) Different dots of data collection can affect the fractal dimension of the mountains of China′s Mainland. 4) The same range of length of side of square grid and dots of data collection can ensure the comparison of fractal dimensions of the mountains of China′s Mainland. The research is helpful to get the more understanding of fractal and fractal dimension,and ensure that the fractal studies would be scientific. 展开更多
关键词 FRACTAL fractal dimension series of square grids China's Mainland
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Coordinated Resource Allocation for Satellite-Terrestrial Coexistence Based on Radio Maps 被引量:5
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作者 Yanmin Wang Zhou Lu 《China Communications》 SCIE CSCD 2018年第3期149-156,共8页
Coexistence of satellite and terrestrial wireless communication systems in the same frequency band is quite promising for addressing the challenge of spectrum scarcity. To cope with the inevitable inter-system interfe... Coexistence of satellite and terrestrial wireless communication systems in the same frequency band is quite promising for addressing the challenge of spectrum scarcity. To cope with the inevitable inter-system interference, radio resource allocation at both sides should be carefully re-optimized. In this paper, we focus on a scenario where a satellite communication system and a terrestrial distributed antenna system(DAS) coexist via spectrum sharing. We particularly utilize the radio map(RM) to reduce the system overhead for channel acquisition. Based on the large-scale channel state information at the transmitter(CSIT), which is derived from the RM, we propose an optimized power allocation scheme to improve the achievable sum rate of the terrestrial system. For the satellite side, an opportunistic user scheduling scheme is presented, to reduce the harmful leakage interference to the terrestrial mobile users. Simulation results demonstrate that the proposed RM-based coordination scheme can significantly promote the performance of satellite terrestrial coexistence, although the small-scale channel fading has been ignored in the formulated optimization. 展开更多
关键词 satellite terrestrial coexistence distributed antenna system (DAS) radio map(RM) resource allocation
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Two-sided Long Baseline Radargrammetry from Ascending Descending Orbits with Application to Mapping Post-seismic Topography in the West Sichuan Foreland Basin 被引量:3
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作者 CHENG Hai-qin CHEN Qiang +2 位作者 LIU Guo-xiang YANG Ying-hui LIU Li-yao 《Journal of Mountain Science》 SCIE CSCD 2014年第5期1298-1307,共10页
One-sided ascending or descending Synthetic Aperture Radar(SAR) stereoradargrammetry has limited accuracy of topographic mapping due to the short spatial baseline(-100 km) and small intersection angle. In order to... One-sided ascending or descending Synthetic Aperture Radar(SAR) stereoradargrammetry has limited accuracy of topographic mapping due to the short spatial baseline(-100 km) and small intersection angle. In order to improve the performance and reliability of generating digital elevation model(DEM) from spaceborne SAR radargrammetry, an exploration of two-sided stereoradargrammetry from the combination of ascending and descending orbits with geometric configuration of long spatial baseline(-1000 km) was conducted in this study. The slant-range geometry between SAR sensors to the earth surface and the Doppler positioning equations were employed to establish the stereoscopic intersection model. The measurement uncertainty of two-sided radargrammetric elevation was estimated on the basis of radar parallax of homogeneous points between input SAR images. Two stereo-pairs of ALOS/PALSAR(Advanced Land Observing Satellite/Phased Array type L-band Synthetic Aperture Radar) acquisitions with the orbital separation almost 1080 km over the west Sichuan foreland basin with rolling topography in southwestern China were employed in the study to obtain the up-to-date terrain data after the 2008 Wenchuan earthquake that hit this area. Thequantitative accuracy assessment of two-sided radargrammetric DEM was performed with reference to field GPS observations. The experimental results show that the elevation accuracy reaches 5.5 m without ground control points(GCPs) used, and the accuracy is further improved to 1.5 m with only one GPS GCP used as the least constraint. The theoretical analysis and testing results demonstrate that the twosided long baseline SAR radargrammetry from the ascending and descending orbits can be a very promising technical alternative for large-area and high accuracy topographic mapping. 展开更多
关键词 Ascending and descending orbits Twosided SAR radargrammetry Long baseline Image parallax Accuracy assessment
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论电报齐价合同
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作者 徐元基 《学术月刊》 CSSCI 北大核心 1989年第10期18-24,6,共8页
齐价合同(common purse system)是关于划一收费标准、确定分配比例的一种经济合同.在晚清,它曾出现于轮船和电报两大行业。电报齐价合同是电报业中外交涉的一个重要问题,它的签订是长期而复杂的过程。其情况究竟如何?它对中国电报总局... 齐价合同(common purse system)是关于划一收费标准、确定分配比例的一种经济合同.在晚清,它曾出现于轮船和电报两大行业。电报齐价合同是电报业中外交涉的一个重要问题,它的签订是长期而复杂的过程。其情况究竟如何?它对中国电报总局究竟是有害还是有利?这些问题都值得进行探讨。 展开更多
关键词 中国电报局 次合同 盛宣怀 恰克图 李鸿章 接线条 公司 陆线 水线 俄国
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Characteristics of coastline changes in China's Mainland since the early 1940s 被引量:26
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作者 HOU XiYong WU Ting +3 位作者 HOU Wan CHEN Qing WANG YuanDong YU LiangJu 《Science China Earth Sciences》 SCIE EI CAS CSCD 2016年第9期1791-1802,共12页
Based on multi-temporal topographic maps, remote sensing images and field surveys covering the entire coastal zone of China's Mainland, the coastlines of six periods since the early 1940s were extracted. Coastline... Based on multi-temporal topographic maps, remote sensing images and field surveys covering the entire coastal zone of China's Mainland, the coastlines of six periods since the early 1940s were extracted. Coastline changes over the last 70 years were then analyzed in terms of coastline structure, coastline fractals, coastline change rates, land-sea patterns, and bay areas. The results showed that mainland coastline structure changed dramatically, and due to the significant coastline artificialization mainly driven by sea reclamation and coastal engineering, the remaining natural coastline merely accounts for less than one third at present. Coastline fractal dimension represented an overall spatial pattern of "north 〈 entirety 〈 south"; however, the discrepancy between the north and south coast was apparently narrowed due to dramatic coastline artificialization of northern China which in turn altered the whole pattern. Patterns and processes of land-sea interchange along the mainland coast were complex and varied spatially and temporally, with over 68% advancing toward sea and 22% retreating toward land. The net growth of land area was nearly 14.2 ×10^3 km2 with an average growth rate of 202.82 km2 al; and coast retreat was characterized by area decrease of 93 bays with a magnitude of 10.1 ×10^3 km2 and an average shrinking rate up to 18.19% or an average shrinking speed up to 144.20 km2 a-1, among which the total area of Bohai shrunk by 7.06%, with an average annual loss amounting to 82 km2. The dramatic coastline changes along China's Mainland have brought about kinds of challenges to the coastal environment, therefore the integrated management, effective environment protection and sustainable utilization of coastlines is urgent. 展开更多
关键词 China Mainland coastline Coastline structure Coastline fractal dimension Coastline change rate Land-Sea change Bay area
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Continental shelf waves forced by nonlinear continental shelf topography 被引量:1
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作者 FENG LiCheng CHAO JiPing 《Science China Earth Sciences》 SCIE EI CAS 2012年第10期1702-1705,共4页
The characteristics of continental shelf waves forced by nonlinear continental shelf topography are studied with a shallowwater model.Results show that there are two topographic Rossby waves and two inertia gravity wa... The characteristics of continental shelf waves forced by nonlinear continental shelf topography are studied with a shallowwater model.Results show that there are two topographic Rossby waves and two inertia gravity waves.The northward propagating topographic Rossby wave couples with the inertia gravity wave into an unstable wave in the long wave band.When the continental slope is increased,the topographic Rossby wave still couples with the inertia gravity wave into an unstable wave,but the frequency decreases.In the South China Sea(SCS),the western boundary can develop an unstable wave because of topographic forcing,nonlinear conditions,and increasing amplitude.It is possible that the unstable wave develops into a vortex.In observations,the SCS has a strong western boundary current and abundant mesoscale vortice.There is a strong relationship between the emergence,disappearance,and movement of the circulation's multi-eddy structure and the seasonal evolvement of the SCS's circulation.This article shows a possible mechanism for the formation of vortices in the SCS. 展开更多
关键词 nonlinear continental shelf topography topographic Rossby wave unstable wave
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Increasing trend of lightning activity in the South Asia region 被引量:3
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作者 Kai Qie Xiushu Qie Wenshou Tian 《Science Bulletin》 SCIE EI CSCD 2021年第1期78-84,M0004,共8页
Lightning is an important natural source of wildfires and oxynitride,and hence significantly influences ecological systems and atmospheric chemistry.Here,we choose South Asia,an important region for global water reall... Lightning is an important natural source of wildfires and oxynitride,and hence significantly influences ecological systems and atmospheric chemistry.Here,we choose South Asia,an important region for global water reallocation and global climate changes,to examine lightning variations based on the longest existing lightning dataset from the OTD/LIS observations.We identify a clear increase in lightning density in the research region,increasing at a rate of 0.096 fl km^(-2)a^(-1)over the last two decades.Multiple linear regression analysis is adopted to identify the main influencing factors among ten potential thermodynamic or microphysical factors and the crucial areas contributing to the increases in lightning.The surface latent heat flux along the west coast of the Indian subcontinent is the largest contributor,explaining52%of the lightning variance and contributing to a 0.025 fl km^(-2)a^(-1)increase.The sea surface temperature in the Arabian Sea,the convective available potential energy(CAPE)over the northwestern Indian subcontinent,and the wind shear along the northwestern coast also make important contributions to the lightning increase,indicating that the thermodynamic effects overwhelm the microphysical effects on lightning activity over the South Asia region. 展开更多
关键词 Lightning activity TREND South Asian monsoon region Thermodynamic and microphysical factors Multiple linear regression analysis
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Prediction of VIGS efficiency by the Sfold program and its reliability analysis in Gossypium hirsutum 被引量:2
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作者 Xiaoyang Ge Jie Wu +10 位作者 Chaojun Zhang Qianhua Wang Yuxia Hou Zuoren Yang Zhaoen Yang Zhenzhen Xu Ye Wang Lili Lu Xueyan Zhang Jinping Hua Fuguang Li 《Science Bulletin》 SCIE EI CAS CSCD 2016年第7期543-551,共9页
Genetic transformation in some plant species, including cotton (Gossypium hirsutum), is hampered by laborious and time-consuming processes and often unachievable. Virus-induced gene silencing (VIGS) by double-stra... Genetic transformation in some plant species, including cotton (Gossypium hirsutum), is hampered by laborious and time-consuming processes and often unachievable. Virus-induced gene silencing (VIGS) by double-stranded RNAs can serve as a reverse-genetics tool to determine gene function. However, knockdown levels vary greatly when using a tobacco rattle virus-based vector that carries different cDNA fragments of a gene. How to choose the optional target fragment for high interference efficiency is very challenging. Addressing this challenge requires increasing the efficacy of small interference RNA (siRNA) in target fragment. Here, we describe a method to assess VIGS efficiency by comparing the following parameters of siRNA in target sequence: the disruptionenergy of the target (△Gdisruption), the differential stability of siRNA duplex ends (DSSE), and the internal stability at positions 9-14 of the siRNA antisense strand (AIS), which are calculated by Sfold program (http://sfold.wadsworth. org). We find that the siRNAs with low mGdisruption, high DSSE and high AIS have high activity and easily result in high VIGS efficiency by experimentally testing the actual knockdown levels of the four target genes, GhPDS, GhCLA1, GhAOS1, and GhCXE1 via choosing different target sequences for each gene. Therefore, the Sfold pro- gram can be used to analyze target sequences when car- rying out VIGS design to increase gene-silencing effects in plants. 展开更多
关键词 VIGS Sfold program SIRNA Targetsequences Gossypium hirsutum
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Continental crust formation at arcs, the arclogite ‘‘delamination''cycle, and one origin for fertile melting anomalies in the mantle 被引量:17
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作者 Cin-Ty A.Lee Don L.Anderson 《Science Bulletin》 SCIE EI CAS CSCD 2015年第13期1141-1156,共16页
The total magmatic output in modern arcs,where continental crust is now being formed, is believed to derive from melting of the mantle wedge and is largely basaltic. Globally averaged continental crust, however, has a... The total magmatic output in modern arcs,where continental crust is now being formed, is believed to derive from melting of the mantle wedge and is largely basaltic. Globally averaged continental crust, however, has an andesitic bulk composition and is hence too silicic to have been derived directly from the mantle. It is well known that one way this imbalance can be reconciled is if the parental basalt differentiates into a mafic garnet pyroxenitic residue/cumulate(‘‘arclogite'') and a complementary silicic melt, the former foundering or delaminating into the mantle due to its high densities and the latter remaining as the crust.Using the Sierra Nevada batholith in California as a case study, the composition of mature continental arc crust is shown in part to be the product of a cyclic process beginning with the growth of an arclogite layer followed by delamination of this layer and post-delamination basaltic underplating/recharge into what remains of the continental crust.A model is presented, wherein continuous arc magmatism and production of arclogites in continental arcs are periodically punctuated by a delamination event and an associated magmatic pulse every *10–30 My. The recycling flux of arclogites is estimated to be *5 %–20 % that of oceanic crust recycling by subduction. Delaminated arclogites have the necessary trace-element compositions to yield time-integrated isotopic compositions similar to those inferred toexist as reservoirs in the mantle. Because of their low melting temperatures, such pyroxenites may be preferentially melted, possibly forming a component of some hotspot magmas. 展开更多
关键词 PYROXENITE ECLOGITE DELAMINATION CUMULATE Continental crust
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Thermal and elemental analysis of the combustion chamber deposits in a large-scale two-stroke marine diesel engine 被引量:2
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作者 ZHANG XuSheng ZENG XiangMing +5 位作者 SUN XiuCheng DENG Biao PENG GuanYun XIE HongLan WU ZhiJun XIAO TiQiao 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2015年第10期1717-1725,共9页
It is of significance to understand the chemical content of carbon deposits in the large-scale two-stroke(LSTS) marine diesel engine because of adverse effect on the engine performance, oil consumption and emissions. ... It is of significance to understand the chemical content of carbon deposits in the large-scale two-stroke(LSTS) marine diesel engine because of adverse effect on the engine performance, oil consumption and emissions. In this work, two different combustion chamber deposits in an LSTS marine diesel engine were studied using thermogravimetry analysis(TGA), elemental analysis(EA) and synchrotron X-ray fluorescence(SXRF). One was on the piston top and the other on the piston land, termed PTCD and PLCD, respectively. For the PTCD sample, the 97% residue in the TGA and 1.4% carbon content in the EA indicated the main compositions of PTCD were metal salts or oxides and ashes, significantly different from the previous findings of the highest carbon content in deposits from the small four stroke engines. The different chemical content between PTCD and PLCD implied higher thermal load in the LSTS marine diesel engine led to a nearly complete thermal decomposition of PTCD. The higher calcium content in PTCD and PLCD indicated the additives of cylinder oil should be the main source of metal content of PTCD and PLCD. Calcium distribution in the SXRF results was indicative of the potential layered structure in PTCD and PLCD. In addition, the appearance of iron on the surface against the piston in PTCD and PLCD indicated iron oxides formation between carbon deposit and piston materials. 展开更多
关键词 combustion chamber deposits thermogravimetry analysis elemental analysis marine diesel engine synchrotron X-rayfluorescence spectrometry
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A potential stratotype for the regional lowermost stage of the continental Paleocene in China 被引量:3
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作者 LI WeiTong LIU GengWu +5 位作者 Dennis R.BRAMAN LI YiBin CAO WeiSheng Don BRINKMAN SHEN Jiao CHEN QingBao 《Science China Earth Sciences》 SCIE EI CAS 2014年第5期1109-1116,共8页
Phanerozoic chronostratigraphic units can only be defined through their lower boundary stratotypes.The lowermost stage of the Paleocene of China,which mainly consists of terrestrial deposits,can only be defined throug... Phanerozoic chronostratigraphic units can only be defined through their lower boundary stratotypes.The lowermost stage of the Paleocene of China,which mainly consists of terrestrial deposits,can only be defined through its lower boundary stratotype,i.e.the continental Cretaceous/Paleogene boundary stratotype.There is no section yet found which contains continuous terrestrial deposits and biostratigraphic records of the Cretaceous-Paleogene transition in Nanxiong,Guangdong and Jiayin,Heilongjiang,there is no evidence for establishing the continental stratotype of the Cretaceous/Paleogene boundary in either area.Therefore,both the"Shanghuan stage"and"Furaoan stage"are not good candidates for the lowermost stage of the Paleocene of China.From the viewpoint of charophytes,the outcrop section of the Dangyang,Hubei Province(Central China)contains the most continuous,abundant and diverse terrestrial biostratigraphic records of the Cretaceous-Paleogene transition,in particular the early Paleocene,known so far in the world.The biostratigraphic records of ostracods in the transition are also continuous,rich,and diverse.The Dangyang outcrop section is the only section known so far in China that is a possible candidate for a continental stratotype of the Cretaceous/Paleogene boundary in China and the section is the only potential section identified to date for establishing the regional lowermost stage of the Paleocene,Paleogene and Cenozoic in China or stratotype section for the stage. 展开更多
关键词 Cretaceous/Paleogene boundary the lowermost stage of Paleocene STRATOTYPE CONTINENTAL CHAROPHYTES Dangyang sec-tion China
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First report of brachiopods with soft parts from the Lower Cambrian Latham Shale (Series 2, Stage 4), California 被引量:2
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作者 Yue Liang Lars E.Holmer +1 位作者 Yazhou Hu Zhifei Zhang 《Science Bulletin》 SCIE EI CAS CSCD 2020年第18期1543-1546,M0003,M0004,共6页
Exceptionally preserved faunas have greatly improved our understanding of animal origin and evolution,and systematic investigations of Cambrian sediments around the world during the last two decades have led to a dram... Exceptionally preserved faunas have greatly improved our understanding of animal origin and evolution,and systematic investigations of Cambrian sediments around the world during the last two decades have led to a dramatic increase in the num-bers of Konservat-Lagerstatten[1]. 展开更多
关键词 CAMBRIAN California LOWER
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