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The first discovery of non-avian dinosaur egg and bone fossils in the Hefei Basin 被引量:1
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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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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 被引量:1
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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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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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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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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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Preservation potential of Cambrian small shelly fossils in different microfacies, North China
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作者 Yazhou Hu Timothy P。Topper +7 位作者 Luke C。Strotz Yue Liang Fan Liu Rao Fu Baopeng Song Zhao Wang Bing Pan Zhifei Zhang 《Geoscience Frontiers》 2025年第5期139-165,共27页
Small shelly fossils(SSFs)have long been recognized as important to the studies of both metazoan evolution and the onset of biomineralization during the Cambrian radiation.The marked decline in the occurrence,diversit... Small shelly fossils(SSFs)have long been recognized as important to the studies of both metazoan evolution and the onset of biomineralization during the Cambrian radiation.The marked decline in the occurrence,diversity and abundance of SSFs in the middle to late Cambrian,when compared with the early Cambrian,has often been regarded as a result of the closure of a phosphatization window.Despite this,there have been numerous and consistent reports of SSFs from the middle Cambrian and younger deposits.To identify possible factors influencing SSF preservation,five microfacies including bioclastic limestone,flat-pebble conglomerates with bioclasts,hummocky cross-stratified grainstone with bioclasts,bioclastic grainstone in hardgrounds and glauconite bioclastic wackstone-packstone,from Cambrian Series 2 to Miaolingian in North China are compared to assess how differences in lithology impact the preservation potential of SSFs.Our results,based on 35,161 SSF specimens from deposits across six sections,suggest that there are still abundant and diverse SSFs in the middle Cambrian of North China preserved in ways not exclusively reliant on the presence of phosphate and that SSF preservation can be linked to the differences in microfacies in the early to middle Cambrian of North China. 展开更多
关键词 Small shelly fossils Shell structure GLAUCONITE Phosphatization window
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中亚造山带中南部索伦缝合带岩石圈结构及其对古亚洲洋演化的制约
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作者 谭晓淼 周建波 +4 位作者 饶莹 王海燕 侯贺晟 李明芮 高锐 《吉林大学学报(地球科学版)》 北大核心 2026年第1期209-218,共10页
中亚造山带经历了古亚洲洋近8亿年的俯冲-增生历史,是地球上规模最大且构造样式最复杂的增生型造山系统之一,完整记录了大洋消减、地壳增生及大陆改造等一系列关键地质事件,为探究显生宙大陆生长机制与古亚洲洋构造域的动力学演化过程... 中亚造山带经历了古亚洲洋近8亿年的俯冲-增生历史,是地球上规模最大且构造样式最复杂的增生型造山系统之一,完整记录了大洋消减、地壳增生及大陆改造等一系列关键地质事件,为探究显生宙大陆生长机制与古亚洲洋构造域的动力学演化过程提供了重要研究窗口。中亚造山带中南段的索伦缝合带,记录了丰富的古亚洲洋演化与消亡信息,被认为是古亚洲洋消亡的最终缝合带。然而,关于该缝合带东向延伸与古亚洲洋在中亚造山带中南段的俯冲极性等关键问题仍存在较大争议。近年来,研究团队在中亚造山带中南段的索伦缝合带地区开展了两条深地震反射大炮剖面研究工作,将探测深度拓展到岩石圈地幔尺度,有效获得了缝合带下方古俯冲带的结构特征。本文总结与横向对比了两条剖面所揭示的深地震结构特征,并结合研究区新近的地球物理数据,综合分析岩石圈尺度的构造变形样式。地球物理证据与地质研究相结合,揭示古亚洲洋在中亚造山带中南段以背向双向俯冲的模式,最终消减于贺根山缝合带与西拉木伦缝合带之间的索伦—突泉一线,并向东延入松辽盆地中部。 展开更多
关键词 中亚造山带 古亚洲洋 岩石圈结构 索伦缝合带 古俯冲带
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云南昆明地区下侏罗统禄丰组恐龙化石的发现及地层学意义
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作者 关奇 莫雄 +6 位作者 钟春荣 孙载波 何世军 刘军平 史劲勇 王涛 王伟 《地质学报》 北大核心 2026年第1期25-33,共9页
通过全面系统的古生物化石产地调查,在云南省昆明市晋宁区唐家山新发现4处恐龙化石点,化石赋存于侏罗系下统禄丰组上部紫红色中层状泥岩夹灰黄、灰紫色薄中层状钙质粉砂岩中,化石顺岩层走向分布,目前发现化石部位主要有背椎、尾椎、股... 通过全面系统的古生物化石产地调查,在云南省昆明市晋宁区唐家山新发现4处恐龙化石点,化石赋存于侏罗系下统禄丰组上部紫红色中层状泥岩夹灰黄、灰紫色薄中层状钙质粉砂岩中,化石顺岩层走向分布,目前发现化石部位主要有背椎、尾椎、股骨和胫骨,部分化石具原地埋藏特征,未经历搬运,保存较完好,通过背椎和部分腰带特征,部分埋藏可以确定为蜥脚型类恐龙。也是继云南夕阳恐龙化石发现之后,昆明地区又一处新发现的恐龙化石产地,进一步拓展了云南恐龙化石分布范围,为深入研究该地区恐龙化石提供新材料。 展开更多
关键词 云南昆明 禄丰组 化石产地 恐龙化石
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污水有机物中化石碳含量的^(14)C测定法研究进展
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作者 绳俊 于鑫 +1 位作者 赵诗怡 陈红 《东华大学学报(自然科学版)》 北大核心 2026年第1期49-55,共7页
污水处理中产生的CO_(2)长期被视为生源性碳排放,未计入碳排放清单,但近年研究揭示污水有机物中化石碳含量显著,其化石源CO_(2)应纳入温室气体排放核算。本文通过系统文献分析与技术比较,综述了^(14)C法测定污水有机物化石碳含量的研究... 污水处理中产生的CO_(2)长期被视为生源性碳排放,未计入碳排放清单,但近年研究揭示污水有机物中化石碳含量显著,其化石源CO_(2)应纳入温室气体排放核算。本文通过系统文献分析与技术比较,综述了^(14)C法测定污水有机物化石碳含量的研究进展,明确了技术优劣与应用场景。采用文献计量与案例分析方法,比较了气体正比计数器、液体闪烁计数器和加速质谱仪(AMS)的性能,证实AMS因高精度(>99.9%)、低样品需求(0.005 g)及短测时(<5 min)等优势成为首选方法。针对AMS制样,优化了酸-碱-酸预处理、静态燃烧CO_(2)萃取及Zn-TiH_(2)/Fe体系石墨化流程,提出标准化操作建议,降低了非放射性碳干扰。未来,AMS技术需进一步降低成本、提升自动化水平,以适应大规模污水处理碳排放监测需求,为精准核算化石源CO_(2)排放提供可靠方法,助力碳中和目标实现。 展开更多
关键词 化石碳 ^(14)C法 加速质谱仪(AMS) ^(14)C样品制备
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“Fossil”汉语译名演变考 被引量:1
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作者 杨丽娟 《地质论评》 CAS CSCD 北大核心 2019年第1期25-28,共4页
"Fossil"来源于拉丁文fossilis,最初用于指地中挖掘物。中文"化石"一词初为矿物、岩石的总称,或用作动词。西文"fossil"先后被汉译为塔形石、殭石等,汉语译名亦几经变化。本文根据晚清西学译著、近代刊... "Fossil"来源于拉丁文fossilis,最初用于指地中挖掘物。中文"化石"一词初为矿物、岩石的总称,或用作动词。西文"fossil"先后被汉译为塔形石、殭石等,汉语译名亦几经变化。本文根据晚清西学译著、近代刊物及教科书中关于化石的介绍,厘清了"fossil"一词译名的演变,指出中文将"fossil"译为"化石"并用于指地中生物遗迹的说法至20世纪初方才确定。 展开更多
关键词 fossil 化石 汉译名 地质学 晚清
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New Discoveries of Phaeophycean Fossils in the Early Cambrian, Haikou, Kunming,Yunnan, Southwest China 被引量:1
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作者 徐兆良 《Acta Botanica Sinica》 CSCD 2001年第10期1072-1076,共5页
The paper deals with the new phaeophycean fossils in the Early Cambrian from Chengjiang Biota at Ercai Village of Haikou, Kunming, Yunnan, Southwest China. Three new taxa, Punctatiopsis latifolia gen. et sp. nov., P. ... The paper deals with the new phaeophycean fossils in the Early Cambrian from Chengjiang Biota at Ercai Village of Haikou, Kunming, Yunnan, Southwest China. Three new taxa, Punctatiopsis latifolia gen. et sp. nov., P. simplex gen. et sp. nov. and Vendotaenia cf. antiqua Gnilovskaya axe described here in detail. These new findings show that the Chengjiang Biota is high in species diversity of fossil algae and might offer new evidence for a better understanding of the Cambrian explosive biological evolution. The fossil genus described here is found to have a close relationship with the living Punctatia based on similar morphology. The results suggest that the Chengjiang Biota in Haikou area of Kunming was living in an intertidal and subtidal seawater environment. 展开更多
关键词 Haikou of Yunnan Early Cambrian phaeophycean fossils
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新疆化石能源产业链韧性评价及障碍因素研究
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作者 王晨 徐妍 《新疆师范大学学报(自然科学版)》 2026年第2期79-88,共10页
新疆是中国西部重要的能源基地,研究其化石能源产业对地区经济发展的作用具有重要意义。文章从产业链韧性的供应保障力、政策响应力、可持续发展力和创新驱动力四个维度出发,结合化石能源产业的特性,构建新疆化石能源产业链韧性综合评... 新疆是中国西部重要的能源基地,研究其化石能源产业对地区经济发展的作用具有重要意义。文章从产业链韧性的供应保障力、政策响应力、可持续发展力和创新驱动力四个维度出发,结合化石能源产业的特性,构建新疆化石能源产业链韧性综合评价指标体系。采用熵值法对2008—2022年新疆煤炭、石油和天然气产业链韧性进行评价,并运用障碍度模型找出影响产业链韧性提升的主要障碍因子。评价结果显示,2008—2022年,新疆煤炭、石油和天然气三大产业链韧性水平整体呈上升趋势。供应保障力和创新驱动力不足是制约新疆煤炭产业链韧性发展的主要原因,供应保障力和政策响应力不足是制约石油和天然气的主要原因。最后,文章提出了优化新疆化石能源产业链韧性的路径与对策建议。 展开更多
关键词 化石能源 产业链韧性 障碍度模型 优化路径
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特朗普“以能源主导世界”的执念与限度
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作者 张锐 岳锋利 《东北亚论坛》 北大核心 2026年第1期93-110,128,共19页
特朗普第二任期重启“能源主导”战略,对内巩固化石能源与核能的主导地位,对外利用能源维护美国在全球秩序中的主导地位。其战略聚焦五大方向:促进本土化石能源开发、强化油气出口与全球市场控制、提升核电产能与技术输出、弱化能源转... 特朗普第二任期重启“能源主导”战略,对内巩固化石能源与核能的主导地位,对外利用能源维护美国在全球秩序中的主导地位。其战略聚焦五大方向:促进本土化石能源开发、强化油气出口与全球市场控制、提升核电产能与技术输出、弱化能源转型政策支持、重塑国内能源治理体系。战略动因涵盖能源实力变现、能源出口霸权构建、人工智能时代的能源需求激增以及国内选举政治考量。该战略强力干扰美国和全球能源转型,加剧世界能源体系的地缘政治化,并对中国能源安全构成挑战。同时,特朗普政府难以逆转美国能源转型,无法操纵油气市场走势,较难扩张地缘政治影响,贸易战还会制造反噬效果。当前中美能源合作空间狭窄,中国需采取灵活合作策略,夯实能源安全基础,加大力度支持新能源产业和全球能源治理。 展开更多
关键词 美国 特朗普 能源战略 化石能源 能源转型
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A general review of studies on fossilization of interlanguage in SLA
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作者 郑辉 郑砚 《Sino-US English Teaching》 2009年第12期38-41,共4页
This paper reviews the articles with "fossilization of interlanguage" as key words in CNKI, and classifies and analyzes them from six aspects: fossilization and FL teaching; concept, origin and avoidance of fossili... This paper reviews the articles with "fossilization of interlanguage" as key words in CNKI, and classifies and analyzes them from six aspects: fossilization and FL teaching; concept, origin and avoidance of fossilization; L1 transfer on fossilization; fossilization and linguistic output; Discourse markers and fossilization; the fossilization of interlanguage from psychology or cognition. It is intended to probe fossilization and its enlightenment and reference to SLA. 展开更多
关键词 INTERLANGUAGE fossilIZATION English teaching
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Research on Non-English Major Undergraduates'Interlanguage Fossilization-A Case Study of HBUE
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作者 孙小军 张黎明 《海外英语》 2013年第9X期20-21,23,共3页
Interlanguage Fossilization is a thorny obstacle to learners in second language acquisition process. Based on data collected from non-English major undergraduates in Hubei University of Economics (HBUE), this paper ca... Interlanguage Fossilization is a thorny obstacle to learners in second language acquisition process. Based on data collected from non-English major undergraduates in Hubei University of Economics (HBUE), this paper carries out an empirical study on students'fossilized errors in the learning process, and aims to explore fossilization causes and propose de-fossilization techniques so as to improve students'language learning. 展开更多
关键词 INTERLANGUAGE fossilIZATION ERROR analysis
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油气两用燃烧器设计及运行参数标定
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作者 张卫军 刘园 史红卫 《节能》 2026年第1期50-53,共4页
由于重油价格的提高及“双碳”目标的提出,设计油气两用燃烧器且油气均能够100%负荷切换使用成为部分石化用户的优先选择。基于热值当量原则,采用4支旋流燃烧器结构,运用气泡雾化技术设计油枪,共用供风系统实现燃料自由切换。结果表明,4... 由于重油价格的提高及“双碳”目标的提出,设计油气两用燃烧器且油气均能够100%负荷切换使用成为部分石化用户的优先选择。基于热值当量原则,采用4支旋流燃烧器结构,运用气泡雾化技术设计油枪,共用供风系统实现燃料自由切换。结果表明,40 t/h锅炉在油、气模式下效率分别达91.8%和93.5%,汽温、气压及蒸发量均满足设计要求,并标定了油枪雾化蒸汽耗量范围。该燃烧器实现油气100%负荷自由切换,可以根据燃料价格灵活选择,节约燃料成本,具有良好的经济性、安全性和环保性。 展开更多
关键词 锅炉 新能源 化石燃料 燃烧器
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胃结石治验1则
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作者 王佳 于福源 《国医论坛》 2026年第2期78-80,共3页
报道威海市中医院院内制剂承气化石丸联合中药离子导入胃肠通1号方治疗胃结石的1则成功案例,并分析其作用机制,以期为临床上胃结石治疗提供具体可行的方案。
关键词 胃结石 内外治法 承气化石丸 中药离子导入 医案医话
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