检索结果-南通市图书馆

Middle Devonian ostracods from Jiwozhai patch reef(Dushan,Guizhou Province,South China):Biostratigraphic and palaeoecological implication

在线全文

学校读者我要写书评

暂无评论

Journal of Palaeogeography 2024年第3期13卷 581-593页

作者： Jun-Jun Song Jia-Yuan Huang Wen Guo Kun Liang Yu-Cong Sun Zhi-Hong Wang Wen-Kun Qie State key laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008Jiangsu ProvinceChina hubei key laboratory of paleontology and geological environment evolution Wuhan Center of China Geological SurveyWuhan 430205Hubei ProvinceChina University of Chinese Academy of Sciences NanjingNanjing 211135Jiangsu ProvinceChina

The Middle Devonian ostracods from the Jiwozhai patch reef in Dushan, Guizhou Province, South China were described for the first time in this study. Twenty-nine species belonging to 20 genera were identified and figured, including a new species named Wangshangkia jiwozhaiensis sp. nov. The ostracod fauna in the Jiwozhai patch reef represents a Givetian age. The ostracod assemblage belongs to the smooth-podocopid association, which is also ecologically equivalent to the Eifelian Mega-Assemblage Ⅲ. This association is indicative of shallow open-marine environments. The Jiwozhai patch reef fauna is primarily comprised of suspension feeders, including filter-feeding ostracods, corals, brachiopods and bryozoans. Ostracods from the Jiwozhai patch reef were compared to the ostracod faunas from Laurentia-Baltica at generic level, which reveals limited faunal exchanges between South China and Laurentia-Baltica during the Middle Devonian.

关键词： Ostracods Givetian Jiwozhai patch reef Dushan Palaeoecology

Highly mass activity electrocatalysts with ultralow Pt loading on carbon black for hydrogen evolution reaction

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 182-190页

作者： Shaorou Ke Yajing Zhao Xin Min Yanghong Li Ruiyu Mi Yangai Liu Xiaowen Wu Minghao Fang Zhaohui Huang Engineering Research Center of Ministry of Education for geological Carbon Storage and Low Carbon Utilization of Resources Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid WastersNational Laboratory of Mineral MaterialsSchool of Materials Science and TechnologyChina University of Geosciences(Beijing)Beijing 100083China

Pt-based nanocatalysts offer excellent prospects for various ***,the low loading of Pt with excellent performance for efficient and stable nanocatalysts still presents a considerable *** this study,nanocatalysts with ultralow Pt content,excellent performance,and carbon black as support were prepared through in-situ ***~2-nm particles uniformly and stably dispersed on carbon black because of the strong s-p-d orbital hybridizations between carbon black and Pt,which suppressed the agglomeration of Pt *** unique structure is beneficial for the hydrogen evolution *** catalysts exhibited remarkable catalytic activity for hydrogen evolution reaction,exhibiting a potential of 100 mV at 100 mA·cm^(-2),which is comparable to those of commercial Pt/C *** activity(1.61 A/mg)was four times that of a commercial Pt/C catalyst(0.37 A/mg).The ultralow Pt loading(6.84wt%)paves the way for the development of next-generation electrocatalysts.

关键词： hydrogen evolution reaction ultralow platinum in-situ synthesis ultrasound

The broad-spectrum adaptations of hominins in the later period of Late Pleistocene of China—Perspectives from the zooarchaeological studies

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2016年第8期59卷 1529-1539页

作者： ZHANG ShuangQuan ZHANG Yue LI Jing Shu GAO Xing key laboratory of Vertebrate evolution and Human Origins Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of Sciences

During the climatic fluctuations in the late Late Pleistocene, hominins in China had experienced some significant changes and adaptations in terms of subsistence strategies. Based on the zooarchaeological analyses of the faunal remains from the Shuidougou site of North China and the Ma'anshan site of South China, the present study demonstratively indicates that the broad-spectrum diet and its closely-related resource intensification for hominins were already at their places roughly at 33–35 cal ka BP. Compared to hominins of earlier period, who would have preferentially exploited large and medium-sized ungulates, hunter-gathers at later period had otherwise incorporated more small-sized animals(especially the quick ones, such as birds and hares) into their diet. Meanwhile, hominins of the later time had also greatly accelerated extractions and exploitations of the nutritional yields from the large and medium-sized animals. However, it seems clear from the current study that there was significant difference regarding the potential mechanisms for the broad-spectrum adaptations of hominins in the late Late Pleistocene of China.

关键词： Late Late Pleistocene Paleolithic Taphonomy Zooarchaeology Broad-spectrum revolution Resource intensification

Paleo-to Mesoproterozoic Tectono-Magmatic Events Recorded in the Huwan Complex from the Dabie Orogen,Central China:Evidence from Petrology and U-Pb Geochronology

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2023年第4期97卷 1150-1162页

作者： ZHU Jiang CHEN Yuqiong CHEN Chao LI Zhanke SHI Xianbin CHEN Song ZOU Yuanbing College of Resources and environment Yangtze UniversityWuhan 430100China hubei key laboratory of Petroleum Geochemistry and environment Yangtze UniversityWuhan 430100China hubei geological Survey Wuhan 430034China hubei key laboratory of Resources and Eco-environment Geology(hubei geological Bureau) Wuhan 430034China School of Earth Resources China University of GeosciencesWuhan 430074China Sixth geological Brigade Hubei Geological BureauXiaoganHubei 432000China

To better understand the Paleo-to Mesoproterozoic tectonic evolution of the Dabie Orogen in the northern margin of Yangtze Block,we present geochronological data for metasedimentary and metavolcanic rocks in the Huwan complex.A total of 385 detrital zircon LA-ICP-MS analyses for metasedimentary rocks yielded three^(207)Pb/^(206)Pb age populations:1.50-1.80 Ga,1.81-1.87 Ga and 1.93-2.0 Ga,providing a maximum depositional timing of ca.1.50 Ga;while metafelsic volcanic gneisses yielded protolith U-Pb ages of 1893±54 *** peak ages are remarkably consistent with the tectonothermal events that occurred in the northern Yangtze Block,indicating the presence of Paleo-to Mesoproterozoic magmatism in the Dabie *** age range of 1.93-2.0 Ga correlates with the Paleoproterozoic collision;the age range of 1.81-1.87 Ga coincides with the period of the post-orogenic extension;and the age range of 1.50-1.80 Ga is interpreted to associate with an extensional *** cores with age of 1732-1965 Ma haveε_(Hf)(t)values ranging from-11.70 to-2.47,indicating that juvenile crust involved in their magma *** to the similar age spectra,we proposed that the nucleus of the Dabie Orogen was close to the Yangtze Block since the *** Huwan complex has an intimate affiliation to the Yangtze Block,and implies multiple orogenic *** was not only experienced the Paleo-Tethys ocean subduction and collision,but also recorded Paleo-to Mesoproterozoic tectono-magmatic events in the Dabie Orogen.

关键词： geochronology detrital zircon Huwan complex Precambrian Yangtze block

Electron Probe Microanalysis of Monazite and Its Applications to U-Th-Pb Dating of geological Samples

在线全文

学校读者我要写书评

暂无评论

Journal of Earth Science 2019年第5期30卷 952-963页

作者： Wenbin Ning Junpeng Wang Deng Xiao Fenfang Li Bo Huang Dong Fu State key laboratory of geological Processes and Mineral Resources Hubei Key Laboratory of Critical Zone Evolution Center for Global Tectonics School of Earth Sciences China University of Geosciences

Electron probe microanalysis(EPMA) dating of monazite has been developed over decades. However, limited by the detectability and analytical sensitivity of dating-related elements(Th, Pb, U and Y), the EPMA dating has been restricted to geological research. In this study, various probe currents, beam diameters and counting times have been utilized on a JEOL JXA-8230 electron microprobe to determine the optimal experimental conditions for measuring Th, Pb, U and Y in monazite. The optimal conditions are:(1) accelerating voltage is 15 k V;(2) probe current is 100 n A;(3) beam diameter is 1 μm;(4) the peak and background counting time of U and Pb are 200 and 100 s;and(5) the peak and background counting time of Th and Y are 100 and 50 s. We apply this method to monazite from garnet-bearing biotite gneiss in the Zanhuang area of the Central Orogenic Belt of the North China Craton. The Pb O-Th O2* isochron age calculated by EPMA data is 1 812±17 Ma(MSWD=2.06), which is similar to the weighted mean 207 Pb/206 Pb age(1 805±12 Ma, MSWD=1.07) obtained by LA-ICP-MS. This study suggests that EPMA dating of monazite as a powerful dating technique can be widely used in geochronological study.

关键词： monazite EPMA dating garnet-bearing biotite gneiss Zanhuang area North China Craton geochemistry

A Middle Triassic stem-neopterygian fish from China sheds new light on the peltopleuriform phylogeny and internal fertilization

在线全文

学校读者我要写书评

暂无评论

Science Bulletin 2016年第22期61卷 1766-1774页

作者： Guang-Hui Xu Xin-Ying Ma key laboratory of Vertebrate evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences

Internal fertilization and viviparity are easily observed and well studied in living neopterygian fishes(14teleostean families), but they are difficult to identify in extinct taxa due to the limitation of the fossil record. The Peltopleuriformes from the Middle to Late Triassic of Europe and South China are a stem group of Neopterygii that may have first evolved internal fertilization and viviparity in this clade because they show a highly modified anal fin in presumed males resembling the intromittent organ in living viviparous teleosts. Until recently, Peltopleurus lissocephalus and P. rugosus from the Ladinian/Anisian boundary(*242 Ma) of Monte San Giorgio area in Switzerland and Italy represent the oldest record of Peltopleuriformes, and the phylogenetic interrelationships of this group remain controversial. Here, we report the discovery of a new peltopleuriform, Peltopleurus nitidus sp. nov., based on eleven well-preserved specimens from the early Middle Triassic(Pelsonian, Anisian, *244 Ma)of Luoping, eastern Yunnan, China. The discovery documents the oldest convincing peltopleuriform, extending the geological range of this clade by proximately two million years. Results of the phylogenetic analysis recover *** at the base of Peltopleuridae, and provide robust support for the sister-group relationships of Peltopleuridae with Thoracopteridae within the Peltopleuriformes. The male anal fin of P. nitidus shows a primitive condition unknown in other peltopleuriforms. Comparative studies of the male anal fin in P. nitidus and other peltopleuriforms shed new light on the internal fertilization in this group.

关键词： Sexual dimorphism Viviparity Peltopleuridae Thoracopteridae Triassic

New specimens of Stenocybus acidentatus(Therapsida: Dinocephalia) from the Middle Permian Dashankou Fauna of China

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2014年第3期88卷 730-737页

作者： JIANG Shan JI Shu-an Institute of Geology Chinese Academy of Geological Sciences key laboratory of Stratigraphy and paleontology Ministry of Land and Resources

The basal dinocephalian clade Stenocybusidae was known from two incomplete specimens representing one generus,Stenocybus,from Dashankou fanua in Yumen,Gansu Province of *** holotype of Stenocybus acidentatus is laterally compressed,making some characters *** we describe two new specimens of Stenocybus acidentatus from the same locality,an anterior portion of skull with articulated jaws,and a right dentary with nearly complete *** show some detailed features on the morphology of the premaxilla,maxilla,nasal,external nares and *** phylogenetic relationship between Stenocybus acidentatus and the relatively large Sinophoneus yumenensis is still difficult to determine,and needs more new complete material and further evidences.

关键词： Dinocephalia Stenocybusidae Dashankou Fauna Middle Permian

New Discovery of Reproductive Organs and Spores in Situ of Ginkgoales and Czekanowskiales from the Middle Jurassic of Shaanxi, China

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2017年第6期91卷 2314-2315页

作者： GUO Caiqing YAO Jianxin key laboratory of Stratigraphy and paleontology Institute of GeologyChinese Academy of Geological Science

Objective Ginkgoales and Czekanowskiales are important components of Mesozoic flora and were widely distributed in the Northern Hemisphere. They are usually preserved together in the stratum. Their fossils are abundant in the Middle Jurassic of Shaanxi Province, but there are no reports on their reproductive organs. Here, we report two male gymnospermous pollen cones from the Middle Jttrassic Yan＇an Formation of the northeast Yulin City, Shaanxi Province, China. The characteristics of the fossils, including those of pollens, have been described in detail. The new specimens were compared with fossils closely similar in morphology, and the taxonomic affinity and systematies were established. The present results offer new fossil materials for the study of taxonomy, evolution, and phytogeography of Ginkgoales and Czekanowskiales.

关键词： New Discovery of Reproductive Organs and Spores Situ of Ginkgoales Czekanowskiales from the Middle Jurassic of Shaanxi

Influence of tectonic preservation conditions on the nanopore structure of shale reservoir:A case study of Wufeng-Longmaxi Formation shale in western hubei area,south China

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2024年第4期21卷 2203-2217页

作者： Meng Xiang Shang Xu Ya-Ru Wen Qi-Yang Gou Bing-Chang Liu National key laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongChina hubei key laboratory of Resources and Eco-environment Geology Hubei Geological SurveyWuhan430034HubeiChina key laboratory of Tectonics and Petroleum Resources Ministry of EducationChina University of GeosciencesWuhan430074HubeiChina

Tectonism is one of the dominant factors affecting the shale pore ***,the control of shale pore structure by tectonic movements is still controversial,which limits the research progress of shale gas accumulation mechanism in the complex tectonic region of southern *** this study,34 samples were collected from two exploratory wells located in different tectonic *** experiments,e.g.,organic geochemistry,XRD analysis,FE-SEM,low-pressure gas adsorption,and high-pressure mercury intrusion,were conducted to fully characterize the shale *** TOC,Ro,and mineral composition of the shale samples between the two wells are similar,which reflects that the shale samples of the two wells have proximate pores-generating capacity and pores-supporting ***,the pore characteristics of shale samples from two wells are significantly *** with the stabilized zone shale,the porosity,pore volume,and specific surface area of the deformed zone shale were reduced by 60.61%,64.85%,and 27.81%,***,the macroscopic and fine pores were reduced by 54.01%and 84.95%,*** activity and uplift denudation are not conducive to pore preservation,and the rigid basement of Huangling uplift can promote pore *** three factors are important reasons for controlling the difference in pore structure between two wells *** established a conceptual model of shale pores evolution under different tectonic preservation *** study is significant to clarify the scale of shale gas formation and enrichment in complex tectonic regions,and helps in the selection of shale sweet spots.

关键词： Shale gas Pore structure Tectonic preservation conditions Shale gas enrichment mechanism