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Science China Earth Sciences 2009年第12期52卷 2029-2039页

作者： YAN DeFei SUN BaiNian XIE SanPing li xiangchuan WEN WenWen Key Laboratory of Western China’s Environmental Systems of the Ministry of Education Lanzhou UniversityLanzhou 730000China LPS Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China

Solenites vimineus (Phillips) Harris (Ginkgophyta) specimens with well-preserved cuticles were collected from five different beds in the oil shale member of the Middle Jurassic Yaojie Formation in the Yaojie Basin, Gansu Province, northwestern China. Gross morphology and fine structures of the fossil leaves were studied, and stomatal parameters were analyzed, according to which, the paleoatmospheric CO2 concentration can be deduced as 1512-1896 ppm that would have caused an increase in mean temperature of about 6.5-7.4℃. Carbon isotopes from the fossils indicate that the carbon isotopic discrimination and water use efficiency (WUE) of S. vimineus were raised nearly obtaining the ideal physiologic state in increased CO2 concentrations and temperature conditions, suggesting that S. vimineus records the paleoenvironmental information of the Middle Jurassic Yaojie Basin and can be used for environmental reconstruction.

关键词： Solenites vimineus stomatal parameters paleo-CO_(2)concentration carbon isotopes Middle Jurassic northwestern China

Anatomical variations of living and fossil liquidambar leaves:A proxy for paleoenvironmental reconstruction

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Science China Earth Sciences 2011年第4期54卷 493-508页

作者： XIAO liang SUN BaiNian li xiangchuan REN WenXiu JIA Hui Key Laboratory of Western China's Environmental Systems of the Ministry of Education and College of Earth and Environment Science Lanzhou University Lanzhou 730000 China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China College of Arts and Sciences Bryant University Smithfield RI 02917 U.S.A. Key Laboratory of Western China's Mineral Resources and Geological Engineering of Ministry of Education Chang'an University Xi'an 710054 China

Based on living ***,we have established that such epidermal cell properties as epidermal cell circumference(Circum.) ,undulation index(UI) ,epidermal cell area(EA) on both upper and lower epidermis and the corresponding epidermal cell density(ED) ,are suitable to differentiate between sun and shade ***,stomatal properties on the lower epidermis,including stomatal length(SL) ,stomatal pore length(PL) and the corresponding stomatal density(SD) ,are reliable parameters to identify sun/shade *** this anatomical approach was applied to 18 leaf remains of *** from the Miocene Xiannanshan Formation,Zhejiang Province(eastern China) ,and the fossil leaves were sorted into two groups,namely,sun and shade *** indicates that anatomical differences between sun and shade leaves found in living species could be used for fossil ***,the variation of UI between sun and shade morphotypes is larger on the upper epidermis as compared with the lower epidermis,showing that the UI on the upper epidermis is more sensitive to environmental *** addition,anatomical features are more variable in sun leaves than in shade leaves for both modern and fossil liquidambar,suggesting sun leaves may be more sensitive to environmental *** leaves can then be a better indicator of paleoenvironmental ***,stomatal parameters of sun morphotype should be adopted on reconstructing paleoenvironments using liquidambar leaf *** the other hand,the three-lobed fossil *** leaf assemblage in the Xiananshan Formation is represented by an almost similar percentage of sun and shade morphotypes(56%and 44%,respectively) ,which is attributed to the short transport before *** a result,identifying sun/shade morphotypes are very useful in reconstructing paleoenvironments based on fossil leaves of liquidambar.

关键词： liquidambarformosana liquidambar miosinica leaf anatomy the Miocene Xiananshan Formation sun and shade leaves

First Record of Cyclocarya from the Early Oligocene Qaidam Basin,North Tibet:Implications for the Paleogeography and Paleoecology

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Journal of Earth Science 2024年第1期35卷 201-211页

作者： Yafei Hou Bowen Song xiangchuan li Fang Han Xu Zhang Kexin Zhang Institute of Geological Survey China University of GeosciencesWuhan 430074China Faculty of Materials Science and Chemistry China University of GeosciencesWuhan 430074China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430074China College of Earth Sciences and Resources&Key Laboratory of Western Mineral Resources and Geological Engineering of the Ministry of Education Chang'an UniversityXi'an 710054China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China School of Earth Sciences East China University of TechnologyNanchang 330013China

As the largest intermontane basin in the northeastern Tibetan Plateau(TP),the Qaidam Basin provides unique insight into paleoclimatic change and its relationship with global change and uplift on the *** this study,based on morphological comparison,fossil fruit of Cyclocarya from the Early Oligocene Shangganchaigou Formation in the Qaidam Basin is assigned as Cyclocarya *** discovery of Cyclocarya *** demonstrates the occurrence of Cyclocarya in the Oligocene sediment in Qaidam *** is the first record of Cyclocarya fossil of Early Oligocene Age in China and indicates that Cyclocarya has existed on the northeastern TP since at least the Early *** living analogues of the current fossil now lives in sub-tropical China,where the East Asian Monsoon is *** the new fossils and previously reported fossil remains of plants and fishes,it can be inferred that the Early Oligocene Qaidam Basin was primarily influenced by westerly circulation and had a relatively warm and humid climate,which was in sharp contrast to the present-day climate in Qaidam Basin.

关键词： biostratigraphy climate change winged-fruit fossil Qaidam Basin Early Oligocene paleoclimate paleogeography

Paliurus(Paliureae,Rhamnaceae) from the Miocene of East China and its Macrofossil-based Phylogenetic and Phytogeographical History

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Acta Geologica Sinica(English Edition) 2014年第5期88卷 1364-1377页

作者： li xiangchuan WANG Haofei LENG Qin XIAO liang GUO Junfeng HE Wenlong College of Earth Sciences and Resources & Key Laboratory of Western Mineral Resources and Geological Engineering of the Ministry of Education Chang'an University School of Earth Sciences & Key Laboratory of Mineral Resources of Western China Lanzhou University Laboratory of Terrestrial Environments Department of Science and TechnologyCollege of Arts and SciencesBryant UniversitySmithfieldRI 02917USA College of Geology and Environment Xian University of Science and Technology

The extant genus Paliurus Miller is divided into P. ramosissimus and P. spina-christi groups and is diagnostically characterized by distinctive orbicular-winged fruits with a trilocular （or often bilocular） ovary and basally triveined leaves with a subentire to serrate margin. Here, structurally preserved winged fruits and associated compressed leaves of Paliurus （Paliureae, Rhamnaceae） are reported from the Middle-Upper Miocene Shengxian Formation of Tiantai, Zhejiang, eastern China. The fruits can be identified as Paliurus microcarpa Xiang-Chuan lisp. nov., the diagnostic characters of external morphology and anatomy of which differ from those of both extant and fossil generic members; the leaves can be designated as Paliurus sp. The species based on winged fruits, P. microcarpa, might represent an ancient intermediate link exclusively known across the P. ramosissimus and P. spina-christi groups, showing a closer affinity to the P. ramosissimus group based on the resemblant smaller fruits with a narrower wing, and to the P. spina-christi group based on the similar wing structure and texture, respectively. Morphological analyses of the present and previous fossil fruit records around the world indicate that diversification of Paliurus had begun in northern transpacific regions by the Late Eocene. The macrofossil records, i.e., fruits and leaves of Paliurus globally when projected on paleoenvironmental maps in view of changing continental positions through time （from Eocene to Miocene） display that the past distribution of the genus was much wider than the present and belongs to a tropical and warm temperate realm of the Northern Hemisphere. Therefore, the modern restricted disjunction in tropical and warm temperate regions of East Asia and South Europe （even eastwards West Asia） might represent glacial refugia for some of the generic ancient lineages to survive severe cold at least since the terminal Pliocene.

关键词： paleobotany systematics Paliurus microcarpa winged fruit phytogeography Middle-LateMiocene Zhejiang Province

Biomolecular Preservation of Miocene Fossil liquidambar from Tiantai,China and Clarkia,USA:Implications for Palaeoenvironmental Study

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Acta Geologica Sinica(English Edition) 2015年第4期89卷 1076-1087页

作者： XIAO liang YANG Hong HE Yuli HE Wenlong li xiangchuan GUO Junfeng HUI Kaixuan College of Earth Science and Resources and Key Laboratory of Western Mineral Resources and Geological Engineering Ministry of EducationChang’an University Laboratory of Terrestrial Environments Department of Science and TechnologyCollege of Arts and SciencesBryant University School of Earth Sciences and Key Laboratory of Mineral Resources in Western China (Gansu Province) Lanzhou University College of Geology and Environment Xi’an University of Science and Technology

Biomolecular characteristics of fossil liquidambar from the Miocene Shengxian Formation, Tiantai, Zhejiang province in eastern China and Miocene Clarkia sediment, Idaho, U.S.A., are obtained by means of Pyrolysis-Gas chromatography-Mass spectrometry analysis （Py-GC-MS）. Their modern equivalent （liquidambarformosana） collected from Nanjing, eastern China, is also analyzed for comparison. The total ion chromatograms （TIC） of modern L. formosana leaves shows abundant pyrolysates of iignin, polysaccharide, aliphatic acid, and amino acid. However, only one polysaccharide molecule, i.e., levoglucosan, is retained in fossil liquidambar leaves from the two Miocene sites with the Tiantai specimen possessing higher intensity. As expected, some lignin pyrolysates including benzene, phenol, guaiacol, vinylphenol and their derivatives, are detected in Miocene Tiantai L. miosinica. However, the lignin components with large molecular weight other than benzene and phenol compounds, are absent in Miocene Clarkia L. pachyphyllum. Abundant pristene and homologous series of n-alk-l-ene/n-alkane pairs with a long retention time are shown in pyrograms of both Tiantai and Clarkia fossils. Based upon our Py-GC-MS data, the molecular preservation in these liquidambar leaf samples can be ranked as the following （from high to low quality respectively）： modern sample 〉Tiantai sample 〉Clarkia sample. Vinyl phenol, an important compound, is present in modern and Tiantai liquidambar leaves, while absent in Clarkia sample, implying that vinyl phenol may be sourced from lignin for liquidambar leaves. Our data support the hypothesis of in situ polymerization for the origin of long-chain homologous series of n-alk-l-ene/n- alkane pairs as leaf alteration products. Our data have implications of the impact of leaf degradation toward biases for palaeoenvironmental reconstruction using stable carbon isotope of fossil plants, and suggest the importance of evaluating molecular preservation of fossil leaf t

关键词： liquidambar Py-GC-MS Miocene Biomolecules palaeoenvironment

First Asian fossil record of Platydictya (Amblystegiaceae) from the lower Miocene and its paleoenvironmental significance

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Frontiers of Earth Science 2023年第1期17卷 351-360页

作者： liyan GUO liang XIAO Ya li xiangchuan li Qin LENG Nan SUN Junfeng GUO Chaofeng FU Jianan WANG Deshuang JI College of Earth Sciences and Resources&Key Laboratory of Western Mineral Resources and Geological Engineering(the Ministry of Education) Chang᾽an UniversityXi᾽an 710054China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China Laboratory for Terrestrial Environments Bryant UniversitySmithfieldRI 02917USA Shaanxi Key Laboratory of Early life and Environments&State Key Laboratoty of Continental Dynamics Northwest UniversityXi᾽an 710069China

Mosses form a diverse land plant group in modern vegetation but have rarely showed up in the fossil record compared with vascular plants. Here, we report an extraordinarily-preserved early Miocene moss fossil from the lower Laoliangdi Formation in the Pingzhuang Coal Mine in Chifeng, Inner Mongolia Autonomous Region, northern China. Although lacking rhizoids and most reproductive organs, the well-preserved fossil allows us to assign it to Platydictya cf. jungermannioides (Amblystegiaceae) based upon its detailed gross and micro-morphology. The diagnostic characteristics include a small-sized body with slender stems bearing spirally arranged ovate-lanceolate leaves that lack costae. Leaf margins are mostly partly entire and partly dentate, a few dentate, and rarely completely entire. It represents the first fossil record of Platydictya in Asia. The specific living microenvironment of the extant P. jungermannioides enriched our understanding of the early Miocene environment that was previously based upon vascular plant fossils and sedimentary lithofacies in the area. Our early Miocene Platydictya cf. jungermannioides fossil lived in a warm and humid lush forest with a dense understory that received adequate water supplies.

关键词： moss the Pingzhuang Coal Mine Inner Mongolia Platydictya paleoenvironment

潞党参四倍体优良株系LDSS-5号的性状观察及多糖含量研究

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中国野生植物资源 2014年第6期33卷 21-25页

作者：李香串山西省医药与生命科学研究院山西太原030006

目的：验证选育出的潞党参四倍体株系LDSS-5号的优良特性,以期解决生产中产量低和抗逆性差的问题.方法：以不同的方法繁殖四倍体株系LDSS-5号,与二倍体植株进行性状比较和多糖含量研究.结果：与二倍体植株比较,该株系在叶、花、茎、根... 详细信息

目的：验证选育出的潞党参四倍体株系LDSS-5号的优良特性,以期解决生产中产量低和抗逆性差的问题.方法：以不同的方法繁殖四倍体株系LDSS-5号,与二倍体植株进行性状比较和多糖含量研究.结果：与二倍体植株比较,该株系在叶、花、茎、根及种子等方面均表现出了巨大型,增产率达到76.0％以上,种子出苗率降低了49.3％～51.1％,且差异显著,三年生根中多糖含量比二倍体根提高3.60％,符合多倍体的特征.结论：潞党参四倍体株系LDSS—5号,性状优良、且有效成分多糖含量高.

关键词：潞党参四倍体性状观察党参多糖

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松属植物地质历史及生物地理演变

地球环境学报 2022年第3期13卷 243-256页

作者：胡祎梁莉娜肖良李相传长安大学地球科学与资源学院西安710054 中国科学院南京地质古生物研究所现代古生物学与地层学国家重点实验室南京210008 西北大学陕西省早期生命与环境重点实验室西安710069

松属(Pinus L.)约113种,是松科现代属中最原始的类群。松属植物种类丰富且研究领域广泛,对其已经积累的资料数据进行系统梳理总结十分必要。本文通过总结国内外松属大化石资料,结合分子系统发育、地质背景和地理隔离事件讨论了其地史分... 详细信息

松属(Pinus L.)约113种,是松科现代属中最原始的类群。松属植物种类丰富且研究领域广泛,对其已经积累的资料数据进行系统梳理总结十分必要。本文通过总结国内外松属大化石资料,结合分子系统发育、地质背景和地理隔离事件讨论了其地史分布及植物地理学意义;该属化石在早白垩世至全新世地层中均有记录。化石证据表明松属很可能在早白垩世(之前)起源于西欧地区,从这一起源地通过北大西洋陆桥扩散到北美洲东部,而东亚的类群可能是从北美洲西部经过白令陆桥散布的。在晚白垩世分化出双维管束松亚属Subgenus Pinus L.及单维管束松亚属Subgenus Strobus(***)Lemmon,前者更接近祖先类群。古新世由于全球显著增温以及白垩纪末期大灭绝等地质事件的影响使松属数量急剧减少,在晚始新世至中新世时期随着气温转凉转冷再次分化扩散,中新世达到其发展高峰且分布面貌与现代类群近似。松属多样性时空历史可能和新生代气候变迁及晚新生代构造运动塑造的山地隆升等环境变化紧密相关。

关键词：松属地理迁移化石记录单维管束松亚属双维管束松亚属

热处理对U76CrRE稀土重轨钢夹杂物和微观组织的影响

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金属热处理 2022年第8期47卷 200-210页

作者：李向川杨吉春白国君樊志明内蒙古科技大学材料与冶金学院内蒙古包头014000

选取U76CrRE钢坯进行1100、1200、1300℃分别保温1、2、3 h的热处理,使用FEI-QUANTA400型扫描电镜对夹杂物进行了观察,利用Axiovert型蔡司光学显微镜对微观组织进行观察,使用Qness-Q10A+全自动显微硬度计进行硬度测试。结果表明,热处理... 详细信息

选取U76CrRE钢坯进行1100、1200、1300℃分别保温1、2、3 h的热处理,使用FEI-QUANTA400型扫描电镜对夹杂物进行了观察,利用Axiovert型蔡司光学显微镜对微观组织进行观察,使用Qness-Q10A+全自动显微硬度计进行硬度测试。结果表明,热处理对U76CrRE稀土重轨钢中夹杂物的作用明显,使夹杂物形状与尺寸都有明显改善,随着加热温度的升高,可以进一步优化MnS和复合夹杂物的形貌和尺寸。在1100℃加热时,MnS与复合夹杂物尺寸随着保温时间的增加而减小,形状得到明显改善;在1200℃加热时,随着保温时间的增加,MnS尺寸减小,复合夹杂尺寸变大。U76CrRE稀土重轨钢的晶粒随着加热温度的升高明显增大,硬度呈现先减后增的趋势,随着保温时间的增加逐渐减小。在1100℃加热时,试验钢中组织皆为马氏体、贝氏体和残留奥氏体,且晶界均不明显;在1200℃与1300℃保温超过1 h后,试验钢中网状渗碳体明显;在1300℃保温1 h时,晶界积碳严重,碳化物未得到有效溶解。在1200℃保温1 h时,试验钢中晶粒均匀,晶界明显,组织主要为残留奥氏体与珠光体,组织均匀。

关键词： U76CrRE稀土重轨钢淬火温度保温时间夹杂物微观组织硬度

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利用激光边带注入法实现光脉冲的减速和存储

量子电子学报 2017年第4期34卷 451-455页

作者：秦青青李凯严祥传江开军中国科学院武汉物理与数学研究所波谱与原子分子物理国家重点实验室湖北武汉430071 中国科学院大学北京100049 中国科学院冷原子物理中心湖北武汉430071

基于激光边带注入法在铷原子蒸气中实现了电磁诱导透明、光脉冲的减速和存储。为实现对铷原子的相干操控,将主激光器的输出锁定在铷87原子D_1线F=1→F′=2的跃迁谱线上,经6.8 GHz电光调制器(EOM)调制后,负一阶频率边带与D1线F=2→F′=2... 详细信息

基于激光边带注入法在铷原子蒸气中实现了电磁诱导透明、光脉冲的减速和存储。为实现对铷原子的相干操控,将主激光器的输出锁定在铷87原子D_1线F=1→F′=2的跃迁谱线上,经6.8 GHz电光调制器(EOM)调制后,负一阶频率边带与D1线F=2→F′=2跃迁频率共振。将负一阶频率边带注入锁定从激光器,主激光器和从激光器输出的两柬激光和铷原子的两基态超精细能级达到双光子共振,实现相干操控铷原子。将主激光器和从激光器输出的两束激光作为探测光和耦合光输入到铷泡中,通过操控两光束的波形和开关观察到电磁诱导透明、光脉冲的减速和存储。

关键词：量子光学光存储电磁诱导透明注入锁定