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Science china earth sciences 2009年第6期52卷 784-796页

作者： zhang huaqiao1,2 & dong xiping1,2 1 school of earth and space sciences,peking university,beijing 100871,china 2 State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing Institute of Geology and Palaeontology,Chinese Academy of sciences,Nanjing 210008,china school of earth and space sciences Peking University Beijing 100871 China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

Although fossils of Orsten-type preservation represented by Skaracarida and Phosphatocopina were first reported from the Middle and Upper Cambrian in western Hunan, South china in 2005, diversified phosphatocopine species have never been appropriately described and elucidated in terms of their evolutionary relationships. Here, we described two new species of Phosphatocopina, Vestrogothia anterispinata sp. nov. and V. bispinata sp. nov. The evolutionary relationship among all the valid species of Phosphatocopina is discussed and the phylogeny of Phosphatocopina is reestablished using cladistic analysis. Accordingly, phosphatocopines primitively evolved along two lineages: one evolved towards the emergence of lobes; the other evolved towards the emergence of dorsal spines. Respectively, lobes originated independently three times, and dorsal spines originated only once. With regard to the dorsal rims, interdorsum originated first, whereas dorsal furrow originated independently twice on the basis of interdorsum. Probably Hesslandona may represent a polyphyletic group, whereas Vestrogothia a monophyletic group.

关键词： fossils of Orsten-type preservation Vestrogothia Phosphatocopina Crustacea evolution phylogeny Cambrian Hunan

Developmental sequence of Cambrian embryo Markuelia

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Chinese Science Bulletin 2007年第7期52卷 929-935页

作者： dong xiping1,2 1 school of earth and space sciences, peking university, beijing 100871, china 2 Laboratory of Palaeobiology & Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of sciences, Nan-jing 210008, china (email: dongxp@***) school of earth and space sciences Peking University Beijing 100871 China

Based on more exquisitely preserved specimens of Markuelia hunanensis recently recovered from Middle and Upper Cambrian in western Hunan and in the light of Synchrotron radiation X-ray tomo-graphic microscopy, the developmental sequence from cleavage through organogenesis to the pre-hatching of Cambrian embryo Markuelia, especially the developmental sequence during the pre-hatching stage, i.e. from the earliest period when the scalids and tail spines only took shape to the latest period (just about hatching), is established. This developmental sequence provides a pattern of embryonic development during the pre-hatching stage, which has not been established in the living scalidophorans (priapulids, loriciferans and kinorhynchs). Thus, it not only enriches our knowledge on the embryonic development of the extant descendants of Markuelia, but also opens a new window to the evolution and development of the animal.

关键词：寒武纪蠕虫化石胚胎发育序列两侧对称动物胚胎

Affinities and functional morphology of the Middle Cambrian ornamented tubules from West Hunan,china

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Progress in Natural Science:Materials International 2004年第10期14卷 67-71页

作者： ZHU Caifa 1,2 and dong xiping 1 (1.school of earth and space sciences,peking university,beijing100871,china 2.university of Petroleum,beijing102249,china) peking Univ Sch Earth & Space Sci Beijing 100871 Peoples R China Univ Petr Beijing 102249 Peoples R China

Problematic phosphatic tubular microfossils with ornamented sculptures are documented to exist in limestones of the up-per Middle Cambrian huaqiao Formation at the Paibi section and the Wangcun section in West Hunan,*** morphological pat-terns,including Ornamented Tube Form I and Ornamented Tube Form II are *** on the analysis of the preservation,wall structure and composition of the fossils,it is deduced that these ornamented tubes may represent carapace spines of some Cambrian arthro-pods with phosphatic carapaces,such as bradoriid *** of functional morphology indicates that the sclerites may rather be considered of a defensive than grasping function on the original organism body.

关键词： Middle Cambrian ornamented tubes affinities functional morphology West Hunan

The developmental trend of labrum and median eyes of Orsten-type preserved Phosphatocopina (Crustacea)

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Science china earth sciences 2010年第1期53卷 18-26页

作者： LIU Zheng 1,2 & dong xiping 1,2 1 school of earth and space sciences,peking university,beijing 100871,china 2 State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing Institute of Geology and Palaeontology,Chinese Academy of sciences,Nanjing 210008,china 1. school of earth and space sciences Peking University Beijing 100871 China2. State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

The Phosphatocopina (Crustacea,Arthropoda) is an important group of 'Orsten-type' preserved *** is resolved as the sister-group of *** we study the labrum,the median eyes,and the inner lamella of Phosphatocopina based on the selected specimens respectively from western Hunan,South china,and *** labrum characters of different species exhibit interspecific *** ratio of labrum length/shield length is significant to the reconstruction of the ontogeny of *** labrum characters should be introduced to the diagnosis of *** the earliest growth stage,the median eyes were inconspicuous,almost as flat as the other area of the ***,with the growth of the individuals they became *** were two obviously concave structures on the ventral side of the hypostome in later stages,which were the positions where the median eyes should have been *** addition,the two modes of preservation of the inner lamella,i.e.,that of shrinking and that of bulging up,are interpreted as the preservational artifact herein.

关键词： Phosphatocopina Crustacea Orsten-type preservation morphology ontogeny Cambrian South china Sweden

Skara hunanensis a new species of Skaracarida (Crustacea) from Upper Cambrian (Furongian) of Hunan,south china

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Progress in Natural Science:Materials International 2007年第8期17卷 934-942页

作者： Liu Jie dong xiping~(**) (school of earth and space Science,peking university,beijing 100871,china) [a]school of earth and space Science Peking University Beijing China

The fossils of Orsten-type preservation are as famous as Chengjiang Fauna in the world,but it was not until 2005 that the Orsten-type fossils represented by Skaraearida and Phosphatocopida were first reported to be found in western Hunan,South china. Here,we report the systematic paleontology of all the exquisitely preserved specimens belonging to *** were found at a same horizon of Upper Cambrian (Furongian) in Wangcun section,western Hunan,south china,assigned to a new species Skara huna- nensis *** hunanensis is characterized by small,soft-integumented,marine forms with slender,annulate body;labrum large and ventrocaudally directed;uniramous antennulae;biramous antennae and mandibulae;maxillas and maxillipeds of the same shape;all postantennular limbs join a short cephalic filter *** body has two tagmata:a cephalon with five pairs of well developed ap- pendages and a trunk composed of 11 ring-shaped conical segments.

关键词： Skara hunanensis Skaracarida Crustacea Upper Cambrian Furongian Hunan

The internal structure of Early Cambrian fossil embryo Olivooides revealed in the light of Synchrotron X-ray Tomographic Microscopy

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Chinese Science Bulletin 2008年第24期53卷 3860-3865页

作者： CHEN Fang1,2 & dong xiping1,2 1 school of earth and space sciences,peking university,beijing 100871,china 2 Laboratory of Paleontology and Stratigraphy,Nanjing Institute of Geology and Paleontology,Chinese Academy of sciences,Nan-jing 210008,china school of earth and space sciences Peking University Beijing 100871 China Laboratory of Paleontology and Stratigraphy Nanjing Institute of Geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China

Countless fossil embryo Olivooides and the hatched larvae,juveniles and adults(the latter two kinds are Punctatus) are recovered by means of acid maceration from the fine-crystalline to medium-crystalline phosphatic limestone and phosphatic micrite of Early Cambrian Kuanchuanpu Formation at the Shizhonggou section,near Kuanchuanpu Village,Ningqiang County,Shaanxi Province,*** the technique of Synchrotron X-ray Tomographic Microscopy,the 3D internal structure of Olivooides and Punctatus is *** morphological and statistic analyses are also given to the stellae structure of Olivooides and Punctatus,which indicates that this structure is a result of adaptive evolution to a lifestyle of fast-attaching after hatching,probably with the function of mucilage *** internal structure of Punctatus is described and *** ovum-like structure,a common internal feature of Punctatus,is considered as the taphonomic structure,rather than eggs or other biological *** structure is thought to be formed after the burial of the animal and before or during the *** original internal structure of Punctatus is assumed to be tabulae-filled,with soft body grown on them.

关键词：同步加速器 X射线显微镜寒武系化石动物区系内部结构

A continuous and long-term in-situ stress measuring method based on fiber optic. Part I: Theory of inverse differential strain analysis

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Petroleum Science 2024年第2期21卷 1171-1189页

作者： Kun-Peng zhang Mian Chen Chang-Jun Zhao Su Wang Yong-dong Fan State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China MOE Key Laboratory of Petroleum Engineering in china university of Petroleum Beijing102249China beijing International Center for Gas Hydrate School of Earth and Space SciencesPeking UniversityBeijing100871China

A method for in-situ stress measurement via fiber optics was proposed. The method utilizes the relationship between rock mass elastic parameters and in-situ stress. The approach offers the advantage of long-term stress measurements with high spatial resolution and frequency, significantly enhancing the ability to measure in-situ stress. The sensing casing, spirally wrapped with fiber optic, is cemented into the formation to establish a formation sensing nerve. Injecting fluid into the casing generates strain disturbance, establishing the relationship between rock mass properties and treatment ***, an optimization algorithm is established to invert the elastic parameters of formation via fiber optic strains. In the first part of this paper series, we established the theoretical basis for the inverse differential strain analysis method for in-situ stress measurement, which was subsequently verified using an analytical model. This paper is the fundamental basis for the inverse differential strain analysis method.

关键词： In-situ stress Fiber optic Orthotropic elastic Differential evolution ABAQUS

Internal Structure of Cambrian Fossil Embryo Markuelia Revealed in the Light of Synchrotron Radiation X-ray Tomographic Microscopy

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Acta Geologica Sinica(English Edition) 2011年第1期85卷 81-90页

作者： CHENG Gong PENG Fan DUAN Baichuan dong xiping school of earth and space sciences Peking University Beijing 100871 China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

In the light of Synchrotron Radiation X-ray Tomographic Microscopy （SRXTM）, the internal structure of Markuelia hunanensis is revealed. In one example, vitrification and peeling show the annuli hidden under the chorion. Sectioning and 3-D reconstruction display an intact digestive tract from the inverted introvert to the terminal anus. The inverted introvert forms a rugby cavum. The following digestive tract is rope-like coiling, parallel to the body axis, about 650 μm in length, and uniform in diameter （-80 μm）. An exquisitely preserved pipe-like structure is hidden in the middle of the rope-like structure, diameter 20--40 lam, with a length of -120 μm. We interpret this pipe-like structure as the possible epidermis of the gut and its surroundings as the possible residue of musculature, similar to that in Priapulans. The two symmetrical rod-shape structures connecting the body wall and digestive tract are interpreted as the possible retractor muscles. After comparing the well preserved Left-form and Right-form Body of Markuelia, we suggest that they may represent a dimorphism. Counted directly, one sample of Markuelia hunanensis possesses 62 annulations and the other 68.

关键词： Markuelia Synchrotron Radiation X-ray Tomographic Microscopy (SRXTM),dimorphism

大气CO_(2)和古地理共同控制新生代印太暖池的演化

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Science Bulletin 2024年第9期69卷 1323-1331页

作者：张冉柳中晖姜大膀俞永强张仲石杨一博谭宁司东张强周鑫 Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD) Nanjing University of Information Science&TechnologyNanjing 210044China Department of earth sciences The University of Hong KongHong Kong 999077China Department of Atmospheric Science School of Environmental StudiesChina University of GeosciencesWuhan 430074China State Key Laboratory of Tibetan Plateau earth System Science Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China school of earth and space sciences University of Science and Technology of ChinaHefei 230026China

The Indo-Pacific warm pool(IPWP) is crucial for regional and global climates. However, the development of the IPWP and its effect on the regional climate during the Cenozoic remain unclear. Here, using a compilation of sea surface temperature(SST) records(mainly since the middle Miocene) and multimodel paleoclimate simulations, our results indicated that the extent, intensity and warmest temperature position of the IPWP changed markedly during the Cenozoic. Specifically, its extent decreased, its intensity weakened, and its warmest temperature position shifted from the Indian to western Pacific Ocean over time. The atmospheric CO_(2) dominated its extent and intensity, while paleogeography, by restricting the distribution of the Indian Ocean and the width of the tropical seaways, controlled the shift in its warmest temperature position. In particular, the eastward shift to the western Pacific Ocean from the middle to late Miocene inferred from compiled SST records likely resulted from the constriction of tropical seaways. Furthermore, by changing the atmospheric thermal structure and atmospheric circulation,the reduced extent and intensity of the IPWP decreased the annual precipitation in the western Indian Ocean, eastern Asia and Australia, while the shift in the warmest temperature position from the Indian to western Pacific Ocean promoted aridification in Australia. Qualitative model-data agreements are obtained for both the IPWP SST and regional climate. From the perspective of past warm climates with high concentrations of atmospheric CO_(2), the expansion and strengthening of the IPWP will occur in a warmer future and favor excessive precipitation in eastern Asia and Australia.

关键词： Indo-Pacific warm pool Cenozoic Atmospheric CO_(2) Paleogeography

Perspective on liquid metal enabled space science and technology

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Science china(Technological sciences) 2020年第7期63卷 1127-1140页

作者： zhang Xu-dong LIU Jing beijing Key Lab of Cryo-Biomedical Engineering and Key Lab of Cryogenics Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China school of Future Technology University of Chinese Academy of SciencesBeijing 100039China Department of Biomedical Engineering School of MedicineTsinghua UniversityBeijing 100084China

With the rapid development of deep space exploration and commercial flight, a series of tough scientific and technological challenges were raised, which urgently require ever advanced technologies to tackle with. Recently, liquid metals, as a kind of newly emerging functional material, are attracting various attention and many breakthroughs have been made on earth. Such a scientific trend also suggests promising approaches for solving those extreme challenges in space environment. To fulfill the increasing needs thus involved, this article is dedicated to systematically introducing liquid metal material and its related disciplines into space science and technology. Firstly, existing application of liquid metal cooling for space nuclear power was summarized. Then, some potential space practices were tentatively put forward, such as liquid metal thermal interface medium,liquid metal phase change material, liquid metal convection cooling, metal alloy thermal storage, liquid metal electromagnetic shielding and liquid metal electronic printing. Fundamental as well as practical issues that would differ with earth were interpreted. Finally, potential liquid metal space experiments were proposed to investigate the liquid metal hydrodynamic characteristic, wettability and phase change mechanism in space physical environment. Overall, liquid metal enabled space science and technology investigation will not only help efficiently solve the current and future space technological problems, but also aid to stimulate the advancement of liquid metal space material science.

关键词： liquid metal space science and technology space nuclear power thermal management electromagnetic shielding electronic printing hydrodynamic characteristics