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Significance of fossilized microbes from the Cambrian stromatolites in the Tarim Basin, Northwest China 被引量:11
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作者 YOU XueLian SUN Shu ZHU JingQuan 《Science China Earth Sciences》 SCIE EI CAS 2014年第12期2901-2913,共13页
Samples of the Cambrian microbial dolomites were collected from Penglaiba section,a well-exposed stratigraphic section in the northwestern area of the Tarim Basin.This study provides an analogue for mediated dolomites... Samples of the Cambrian microbial dolomites were collected from Penglaiba section,a well-exposed stratigraphic section in the northwestern area of the Tarim Basin.This study provides an analogue for mediated dolomites that can precipitate in microbial mats and biofilms.The Cambrian stromatolitic dolomites were studied using high-resolution scanning electron microscopy.The results are as follows:(1)dolomites with 50 nm to 100 nm spherical nanostructures are aggregated into minerals of larger sphericities;(2)nanospherical dolomites of 50 nm to 170 nm diameter are densely arranged as dumbbell-shaped or chained aggregates;(3)silicified filaments,as well as dumbbell-shaped and chain arrangements,are preserved as important microstructures.On the basis of sedimentological,compositional,geochemical,and petrographic data,the microstructures were interpreted as nanoglobules that function as bacteria in the nucleation and filament mineralization stages.The microstructures function as such because they are wrapped in extracellular polymeric substance(EPS)or mucus and mineralized fossils.Silicification accounts for the exceptional preservation of microbial mat structures,including biofilms,as well as filamentous and coccoid microbes.In addition,EPS process is capable of binding different elements,with preference for Si,Mg,and Ca.Such suitable composition favors microbe mineralization and dolomite nucleation on organic substrates.These microscopic structures suggest bacterial mineralization and provide visual evidence for the origin of microbial dolomites. 展开更多
关键词 CAMBRIAN STROMATOLITE fossilized microbe mediated dolomite
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Fossilized metazoan embryos——the historical testimony of the Cambrian explosion 被引量:1
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作者 YIN Chongyu 《Chinese Science Bulletin》 SCIE EI CAS 1999年第9期770-771,共2页
IN zoology, the developmental stage of individual from zygote to hatching was called embryo. The modem embryology is a branch of study on the organism’ s embryos. The palaeoembryology is a new field in palaeontology,... IN zoology, the developmental stage of individual from zygote to hatching was called embryo. The modem embryology is a branch of study on the organism’ s embryos. The palaeoembryology is a new field in palaeontology, and it has not been considered an important field before, because the invertebrate’s eggs or embryos are minute size and without mineralized envelope. Until now, fossilized eggs of invertebrates in Cambrian have been rarely reported and most of them are small globular structures without recognizable features. Other reported fossilized embryos found from Middle Cambrian are spherical with a 展开更多
关键词 fossilized metazoan embryos
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The first discovery of non-avian dinosaur egg and bone fossils in the Hefei Basin
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作者 WANG Qiang DONG Zhe +4 位作者 MAO Lei ZHU Xu-Feng CHEN Yan-Bin HUANG Jian-Dong DING Hai-Dong 《古脊椎动物学报(中英文)》 北大核心 2025年第3期248-252,共5页
This report is about the first record of non-avian dinosaur eggs in the Hefei Basin,Anhui Province,China.Based on the combination of elongated egg body,linear ridges on the outer surface and two structure layer,the eg... This report is about the first record of non-avian dinosaur eggs in the Hefei Basin,Anhui Province,China.Based on the combination of elongated egg body,linear ridges on the outer surface and two structure layer,the eggs can be referred to Elongatoolithidae.The gradual boundary between the cone and the column layers as well as the relative thin eggshell(less than 1 mm)indicates its affinity within Elongatoolithus.The eggs are identified as Elongatoolithus oosp.,as they were severely compressed and experienced erosion on both inner and outer surfaces.The discovery of egg fossil in the Hefei Basin offers evidence for stratum comparison in this region and supplements the diversity of egg fossils in Anhui.Meanwhile,this discovery also enriches the paleogeographic distribution of elongatoolithids. 展开更多
关键词 Hefei Basin Upper Cretaceous Zhangqiao Formation egg fossil Elongatoolithidae
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Early Miocene micromammal fossils from Gucheng in Linxia,Gansu,China
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作者 WANG Ban-Yue QIU Zhu-Ding LI Lu 《古脊椎动物学报(中英文)》 北大核心 2025年第2期102-132,共31页
The micromammal fossils collected from the Shangzhuang Formation of the Linxia Basin,Gansu,are described here.The assemblage consists of 16 species of 13 genera belonging to 7 families,including one new species and on... The micromammal fossils collected from the Shangzhuang Formation of the Linxia Basin,Gansu,are described here.The assemblage consists of 16 species of 13 genera belonging to 7 families,including one new species and one taxon previously unknown from China.Among them 5 genera are Oligocene holdovers and 11 genera/species are known to make their first appearances in Early Miocene,indicating an Early Miocene age for the Gucheng Fauna.The absence of Oligocene survivors such as Tataromys,Yindirtemys,Eucricetodon and Tachyoryctoides,which usually occur in the Xiejian age of Early Miocene,and the presence of newcomers Protalactaga,Megacricetodon and Gobicricetodon,that made their first appearance only in the Shanwangian age of late Early Miocene,suggest that the Gucheng Fauna is of a later age of Early Miocene.The new species,Sinolagomys guchengensis,showing more derived morphology than in S.ulunguensis,seems to support an assessment of the fauna in Shanwangian age.Thus,the Gucheng Fauna may belong to late Early Miocene Shanwangian,partially equivalent to MN 3/4 of the European land mammal zonation.Ecological analysis of the fauna indicates that the palaeoecological condition of the Gucheng area might still be a predominantly arid shrub-steppe in late Early Miocene. 展开更多
关键词 Gucheng LINXIA GANSU late Early Miocene Shangzhuang Formation micromammal fossils
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Shortening the formation time of oxide thin film photoelectrodes from hours to seconds
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作者 Zili Ma Zeyu Li Jun Lv 《Chinese Journal of Structural Chemistry》 2025年第4期14-17,共4页
Beginning from the industrial revolution,non-renewable fossil fuels have powered the population growth and economic expansion.However,the overdependence of such energy sources leads to serious eco-crisis and energy se... Beginning from the industrial revolution,non-renewable fossil fuels have powered the population growth and economic expansion.However,the overdependence of such energy sources leads to serious eco-crisis and energy security issues.As shown in Fig.1,the emissions of CO_(2) greenhouse gas are rising year by year because of the significant amount consumption of fossil energy[1].Searching sustainable energy technologies to achieve carbon neutrality has thus become an urgent task for the future of human society[2].As the most abundant and inexhaustible energy source,sunlight has brought dawn to the opportunities for a sustainable society.Owing to the diurnal and seasonal cycles,the solar energy has the intermittent character,which limits its applications. 展开更多
关键词 carbon neutrality fossil fuels sustainable energy technologies non renewable fossil fuels oxide thin film photoelectrodes formation time fossil energy searching population growth
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Cobalt-modified nitrogen-doped carbon nanotubes as bifunctional catalysts for one-pot synthesis of 2,5-diformylfuran from glucose
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作者 Trinh Hao Nguyen Dao Anh Le Nguyen +4 位作者 Duy Quoc Mai Mai Ngoc Thi Le Diep Dinh Le Ha Bich Phan Phuong Hoang Tran 《Journal of Energy Chemistry》 2025年第4期440-447,共8页
In the past century,industrial and economic growth relied heavily on fossil fuels such as coal,oil,and natural gas.As the society energy demands continue to grow,these fossil fuel reserves are depleted,leading to sign... In the past century,industrial and economic growth relied heavily on fossil fuels such as coal,oil,and natural gas.As the society energy demands continue to grow,these fossil fuel reserves are depleted,leading to significant environmental issues[1].Currently,sustainable biomass resources have attracted much attention as potential substitutes to fossil fuels for producing biofuels and commodity chemicals[2]. 展开更多
关键词 commodity chemicals fossil fuels diformylfuran fossil fuel one pot synthesis natural gasas bifunctional catalysts cobalt modified nitrogen doped carbon nanotubes
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Classification and Age Estimation of Fossil Shells from Ban Sap Noi Geopark in Thailand,through the Material Characterization Techniques
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作者 Sirikorn Pongtornkulpanich Patcharin Naemchanthara +3 位作者 Kridsada Faksawat Weeranut Kaewwiset Pichet Limsuwan Kittisakchai Naemchanthara 《Journal of Wuhan University of Technology(Materials Science)》 2025年第3期635-643,共9页
The fossil shells on the sedimentary rocks were collected from The Historical Park,Ban Sap Noi Geopark,Phetchabun Province,Thailand.However,the fossils remained in this area were investigated on the characteristic spe... The fossil shells on the sedimentary rocks were collected from The Historical Park,Ban Sap Noi Geopark,Phetchabun Province,Thailand.However,the fossils remained in this area were investigated on the characteristic species only in geological studies with taxonomy for fossil age predicting.To fill up the gap of these studies,the material characterization techniques were used to study the chemical composition and structure of fossil shells I,II and III.The results clearly showed that the morphologies of all fossil shells were Brachiopod fossils with different species.The functional group and elemental composition of all fossil shells showed that the high content of calcium carbonate was a major composition.In addition,the high content of quartz indicated the silica precipitation phenomenon in all fossil shells.The element composition of cross-sectional morphology and energy dispersive spectroscope (EDS mapping) were used to confirm the presence of Si element in each zone of fossil shells.The crystal structures of all fossil shells were investigated and indicated that the calcium carbonate compound was a calcite phase and silicon dioxide compound was a quartz phase.Moreover,the crystal structure of quartz phase was used to calculate the crystallinity index.The crystallinity index values in all fossil shells indicated a well-crystallized quartz.The age of fossil shells was estimated and found to be brachiopod fossil in carboniferous period with the age of about 359.2 to 299.0 million years. 展开更多
关键词 fossil shell Ban Sap Noi Geopark crystallinity index fossil age carboniferous period
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Heterogeneous occurrence of evergreen broad-leaved forests in East Asia:Evidence from plant fossils
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作者 Jiagang Zhao Shufeng Li +8 位作者 Jian Huang Wenna Ding Mengxiao Wu Tao Su Alexander Farnsworth Paul J.Valdes Linlin Chen Yaowu Xing Zhekun Zhou 《Plant Diversity》 2025年第1期1-12,共12页
Evergreen broad-leaved forests(EBLFs) are widely distributed in East Asia and play a vital role in ecosystem stability. The occurrence of these forests in East Asia has been a subject of debate across various discipli... Evergreen broad-leaved forests(EBLFs) are widely distributed in East Asia and play a vital role in ecosystem stability. The occurrence of these forests in East Asia has been a subject of debate across various disciplines. In this study, we explored the occurrence of East Asian EBLFs from a paleobotanical perspective. By collecting plant fossils from four regions in East Asia, we have established the evolutionary history of EBLFs. Through floral similarity analysis and paleoclimatic reconstruction, we have revealed a diverse spatio-temporal pattern for the occurrence of EBLFs in East Asia. The earliest occurrence of EBLFs in southern China can be traced back to the middle Eocene, followed by southwestern China during the late Eocene-early Oligocene. Subsequently, EBLFs emerged in Japan during the early Oligocene and eventually appeared in central-eastern China around the Miocene. Paleoclimate simulation results suggest that the precipitation of wettest quarter(PWet Q, mm) exceeding 600 mm is crucial for the occurrence of EBLFs. Furthermore, the heterogeneous occurrence of EBLFs in East Asia is closely associated with the evolution of the Asian Monsoon. This study provides new insights into the occurrence of EBLFs in East Asia. 展开更多
关键词 Evergreen broad-leaved forests(EBLFs) Plant fossils East Asia PALEOCLIMATE PALEOVEGETATION Asian monsoon
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Late Cretaceous marine incursion into central Africa
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作者 Hong Xiao Mei-Jun Li +3 位作者 Benjamin J.Nettersheim Bing You Man Lu Ding-Sheng Cheng 《Petroleum Science》 2025年第5期1811-1822,共12页
The Late Cretaceous global transgression is one of the best documented episodes of continental submergence events.The extent of transgression of the Neotethys Ocean into the African continent is generally thought to b... The Late Cretaceous global transgression is one of the best documented episodes of continental submergence events.The extent of transgression of the Neotethys Ocean into the African continent is generally thought to be limited to north Africa.Here,we describe transgression traces in the Muglad Basin in central Africa that indicate a greater spatial extend of the Neotethys during the late Cretaceous.A series of molecular markers detected in the Upper Cretaceous Santonian-Maastrichtian sediments of the Muglad Basin are typical for marine depositional conditions and differ from those in the typical lacustrine sediments of the Lower Cretaceous Barremian-Aptian.Combining the geological-geochemical implications of these markers with the paleogeographic,paleontological and lithological records,we propose that the Muglad Basin received intermittent marine inundations during the Santonian-Maastrichtian stages(86.3-66.0 Ma)and these special molecular markers are therefore the products of seawater incursion.Consequently,this study proposes that the transgression extent of the Neotethys Ocean into the African continent southern extended to the central Africa during the Late Cretaceous. 展开更多
关键词 Late Cretaceous transgression Molecular fossils Dinosteranes Neotethys ocean Central Africa
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CCUS:A Panacea or a Placebo in the fight against climate change?
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作者 Yuxin Zhao 《Green Energy & Environment》 2025年第2期239-243,共5页
Carbon Capture,Utilization,and Storage(CCUS)is a crucial technology for achieving carbon neutrality,but it faces significant challenges.Despite substantial investments and policy support,CCUS projects have underperfor... Carbon Capture,Utilization,and Storage(CCUS)is a crucial technology for achieving carbon neutrality,but it faces significant challenges.Despite substantial investments and policy support,CCUS projects have underperformed due to technical difficulties,high costs,and controversies surrounding the fossil fuel industry's involvement.The effectiveness and feasibility of CCUS in reducing carbon emissions remain uncertain.This viewpoint provides a comprehensive analysis of the current state of CCUS technology,examining its potential to reduce carbon emissions,the challenges hindering its deployment,and the strategies needed to overcome these barriers.We discuss the need for a combinatorial approach to unlock CCUS's full potential,and also emphasize the importance of selecting optimal CO_(2)utilization pathways to maximize economic benefits and CO_(2)absorption.Although CCUS faces technical,economic,and social barriers,it can still play a valuable role in mitigating emissions from hard-to-abate sectors when supported by comprehensive strategies and collaborative efforts among governments,industries,and research institutions.By addressing these challenges and investing in innovation,CCUS can contribute to achieving carbon neutrality and building a sustainable,low-carbon future. 展开更多
关键词 CCUS Carbon neutrality Net-zero emissions Fossil fuel industry Sustainable development
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An improved method for extracting cellulose from fossil wood and its paleoclimatic implications
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作者 Donghao WU Xin WANG +6 位作者 Yang DENG Mi WANG Gang HU Xuan DING Linlin GAO Keyan FANG Xiaohua GOU 《Frontiers of Earth Science》 2025年第3期380-388,共9页
The stable carbon isotope composition of cellulose(δ^(13)Ccell)in fossil wood is valuable for reconstructing past climatic and ecological changes,on seasonal to decadal timescales.However,extracting cellulose from fo... The stable carbon isotope composition of cellulose(δ^(13)Ccell)in fossil wood is valuable for reconstructing past climatic and ecological changes,on seasonal to decadal timescales.However,extracting cellulose from fossil wood is challenging,leading to a lack ofδ^(13)Ccell data over deep time;moreover,there is a debate about whether the stable carbon isotope composition of whole wood(δ^(13)Cwood)can reliably reflect past paleoclimatic or palaeoecological conditions.Here,we present an improved method for extracting cellulose from fossil wood.We initially used conventional methods to extract cellulose from a fossil wood sample a drill core from the Yuncheng Basin,near the Chinese Loess Plateau;however,we were unsuccessful.Subsequently,we successfully extracted cellulose and recovered 94%of the cellulose after modifying the conventional procedure.This involved increasing the reaction time during lignin removal,reducing the concentration of NaOH solution during hemicellulose removal,and employing multiple centrifugation steps for sample separation instead of a single step.We examined the relationship betweenδ^(13)Ccell andδ^(13)Cwood values(n=136),and the results revealed a positive correlation between them(R^(2)=0.51,P<0.001).This indicates thatδ^(13)Cwood is a dependable proxy for qualitative paleoclimatic reconstruction.However,the apparent enrichment factorεbetweenδ^(13)Ccell andδ^(13)Cwood values varied between samples,highlighting the need for caution when using records ofδ^(13)Cwood for quantitative paleoenvironmental reconstruction. 展开更多
关键词 fossil wood stable carbon isotopes tree rings cellulose extraction Paleoclimatic reconstruction
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S-scheme heterojunction with intraband defect levels for artificial photosynthesis
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作者 Xiaoming Liu Zhifeng Jiang 《Chinese Journal of Catalysis》 2025年第3期5-7,共3页
The increasing dependence on fossil fuels and the consequent CO_(2)emissions have prompted urgent energy and environmental challenges[1,2].Solar-driven CO_(2)conversion into value-added fuels offers a sustainable and ... The increasing dependence on fossil fuels and the consequent CO_(2)emissions have prompted urgent energy and environmental challenges[1,2].Solar-driven CO_(2)conversion into value-added fuels offers a sustainable and promising solution to these issues[3].However,the practical implementation of CO_(2)photoreduction is constrained by low efficiency,primarily due to the rapid recombination of photogenerated electron-hole pairs[4]. 展开更多
关键词 artificial photosynthesis fossil fuels intraband defect levels HETEROJUNCTION
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Editorial for the Special Issue on Carbon Capture, Utilization, and Storage
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作者 Gensheng Li Jinsheng Sun +1 位作者 Zhangxin Chen Zhenhua Rui 《Engineering》 2025年第5期1-2,共2页
Global climate change has become one of the most pressing challenges of the 21st century.As anthropogenic CO_(2) emissions from fossil fuel consumption and industrial processes continue to disrupt Earth’s carbon cycl... Global climate change has become one of the most pressing challenges of the 21st century.As anthropogenic CO_(2) emissions from fossil fuel consumption and industrial processes continue to disrupt Earth’s carbon cycle,atmospheric CO_(2) concentrations have reached unprecedented levels-exceeding 420 parts per million(ppm)in 2023 compared to pre-industrial 280 ppm.This rapid accumulation of greenhouse gases has resulted in measurable con-sequences including rising global temperatures,ocean acidifica-tion,and increased frequency of extreme weather events. 展开更多
关键词 fossil fuel consumption greenhouse gases global climate change industrial processes global temperaturesocean carbon capture carbon cycleatmospheric UTILIZATION
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Top-down Constraint on Regional Fossil Fuel CO_(2)Emissions in China Using GOSAT and OCO-2 Satellite XCO_(2)Retrievals:A Case of the COVID-19 Lockdown
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作者 Wenyuan CHANG Dongxu YANG +1 位作者 Xiao TANG Lei KONG 《Advances in Atmospheric Sciences》 2025年第8期1566-1579,共14页
The challenge of establishing top-down constraints for regional emissions of fossil fuel CO_(2)(FFCO_(2))arises from the difficulty in distinguishing between atmospheric CO_(2)concentrations released from fossil fuels... The challenge of establishing top-down constraints for regional emissions of fossil fuel CO_(2)(FFCO_(2))arises from the difficulty in distinguishing between atmospheric CO_(2)concentrations released from fossil fuels and background variability,particularly owing to the influence of terrestrial biospheric fluxes.This necessitates the development of a regional inversion methodology based on atmospheric CO_(2)observations to verify bottom-up estimations independently.This study presents a promising approach for estimating China's FFCO_(2)emissions by incorporating the model residual errors(MREs)of the column-averaged dry-air mole fractions of CO_(2)(XCO_(2))from FFCO_(2)emissions(MREff)retained in the analysis of natural flux optimization.China's FFCO_(2)emissions during the COVID-19 lockdown in 2020 are estimated using the GEOS-Chem adjoint model.The relationship between the MREff and FFCO_(2)is determined using the model based on a regional FFCO_(2)anomaly suggested by posterior NOx emissions from air-quality data assimilation.The MREff is typically one-tenth in magnitude,but some positively skewed outliers exceed 1 ppm because the prior emissions lack lockdown impacts,thereby exerting considerable observation forcing given the satellite retrieval uncertainties.We initialize the FFCO_(2)with posterior NOx emissions and optimize the colinear emission ratio.Synthetic data experiments demonstrate that this approach reduces the FFCO_(2)bias to less than 10%.The real-data experiments estimate 19%lower FFCO_(2)with GOSAT XCO_(2)and 26%lower with OCO-2 XCO_(2)than the bottom-up estimations.This study proves the feasibility of our regional FFCO_(2)inversion,highlighting the importance of addressing the outlier behaviors observed in satellite XCO_(2)retrievals. 展开更多
关键词 XCO_(2) fossil fuel emissions adjoint model GEOS-CHEM COVID-19
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Fossil Crania from Central China Revise Family Tree of Human Beings
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作者 SONG Jianlan 《Bulletin of the Chinese Academy of Sciences》 2025年第3期153-156,共4页
With a mixed look of both Homo erectus and Homo sapiens,Yunxian Man,who could have connected different ancestors of ours,helps unveil a stage of fast diversification in human evolution.
关键词 family tree homo sapiens homo erectus homo sapiensyunxian fossil crania mixed look central china human beings
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