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A new Early Cretaceous lizard with well-preserved scale impressions from western Liaoning, China

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Progress in Natural science:Materials International 2005年第2期15卷 67-73页

作者： JI Shu’an*(school of earth and space {3.s, peking university, beijing 100871, China) school of earth and space {3.s Peking University Beijing 100871 China

A new small lizard, Liaoningolacerta brevirostra gen. et sp. nov., from the Early Cretaceous Yixian Formation of western Liaoning is described in detail. The new specimen was preserved not only by the skeleton, but also by the exceptionally clear scale impressions. This lizard can be included within the taxon Scleroglossa based on its 26 or more presacrals, cruciform interclavicle with a large anterior process, moderately elongated pubis, and slightly notched distal end of tibia. The scales vary evidently in size and shape at different parts of body: small and rhomboid ventral scales, tiny and round limb scales, and large and longitudinally rectangular caudal scales that constitute the caudal whorls. This new finding provides us with more information on the lepidosis of the Mesozoic lizards.

关键词： new genus Squamata skeleton lepidosis Early Cretaceous western Liaoning

Some basic concepts and problems on the petrogenesis of intra-plate ocean island basalts

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Chinese science Bulletin 2009年第22期54卷 4148-4160页

作者： NIU Yaoling1,2,3.1 Department of earth sciences, Durham university, Durham DH1 3.E, UK 2 {3. of earth sciences and Resources, China university of Geosciences, beijing 100083. China 3.school of earth and space sciences, peking university, beijing 100871, China Department of earth sciences Durham University Durham DH1 3LE UK school of earth sciences and Resources China University of Geosciences Beijing 100083 China school of earth and space {3.s Peking University Beijing 100871 China

Basaltic magmatism that builds intra-plate ocean islands is often considered to be genetically associated with "hotspots" or "mantle plumes". While there have been many discussions on why ocean island basalts (OIB) are geochemically highly enriched as an integral part of the mantle plume hypothesis, our current understanding on the origin of OIB source material remains unsatisfactory, and some prevailing ideas need revision. One of the most popular views states that OIB source material is recycled oceanic crust (ROC). Among many problems with the ROC model, the ocean crust is simply too depleted (e.g., [La/Sm]PM > 1) OIB. Another popular view states that the enriched component of OIB comes from recycled continental crust (RCC, i.e.; terrigenous sediments). While both CC and OIB are enriched in many incompatible elements (e.g., both have [La/Sm]PM >>1), the CC has characteristic enrichment in Pb and deletion in Nb, Ta, P and Ti. Such signature is too strong to be eliminated such that CC is unsuitable as source material for OIB. Plate tectonics and mantle circulation permit the presence of ROC and RCC materials in mantle source regions of basalts, but they must be volumetrically insignificant in contributing to basalt magmatism. The observation that OIB are not only enriched in incompatible elements, but also enriched in the progressively more incompatible elements indicates that the enriched component of OIB is of magmatic origin and most likely associated with low-degree melt metasomatism. H2O and CO2 rich incipient melt may form in the seismic low velocity zone (LVZ). This melt will rise because of buoyancy and concentrate into a melt rich layer atop the LVZ to metasomatize the growing lithosphere, forming the metasomatic vein lithologies. Erupted OIB melts may have three components: (1) fertile OIB source material from depth that is dominant, (2) the melt layer, and (3. assimilation of the metasomatic

关键词：岩石成因论海洋 OIB 矿物学

Is the PhyloCode better than Linnaean system?—— New development and debate on biologi-cal nomenclatural issues

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Chinese science Bulletin 2003年第3期48卷 308-312页

作者： GAO Keqin & SUN Yuanlin school of earth and space {3.s, peking university, beijing 100871, China school of earth and space {3.s Peking University Beijing 100871 China

The Linnaean system provides ultimate means governing biological nomenclature and classification. With series of modification, this system has admirably served bio-logical sciences for some 250 years. The new PhyloCode, however, advocates the phylogenetic nomenclature that radically alternates the current nomenclatural rules. The new proposals upset many systematic biologists and have provoked hot debate on nomenclatural issues. Binomial no-menclature and hierarchical classification are the key com-ponents of the Linnaean system. Proposed abandonment of these in the PhyloCode is widely criticized for it would not help to promote systematics but create chaos. It is not the Linnaean system but the phylogenetic nomenclature that should be abandoned.

关键词：生物分类生物命名法林奈系统系统代码法特点

Raman OH stretching vibration of ice Ih

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Progress in Natural science:Materials International 2009年第11期19卷 1651-1654页

作者： Qiang Sun~*,Haifei Zheng The school of earth and space {3.s,peking university,beijing 100871,China [a]The school of earth and space {3.s Peking University Beijing 100871 China

From our recent research on ice Ih(hexagonal ice),we deduce that free OH groups exist at the ice surface and that dangling OH influences the interior of the proton-disordered ***,exploiting recent research by others on water molecular clusters,we propose a new interpretation for the Raman OH stretching vibration of ice *** deconvolute the Raman OH stretching vibration of ice Ihinto four sub-bands,with each sub-band being ascribed to OH vibrations engaged in different types of hydrogen bonding.

关键词： Raman Hydrogen bonding Ice I_h

Biodegradation of heavy oils by halophilic bacterium

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Progress in Natural science:Materials International 2009年第8期19卷 997-1001页

作者： Ruixia Hao , Anhuai Lu school of earth and space {3.s, peking university, beijing 100871, China [a]school of earth and space {3.s Peking University Beijing 100871 China

A halophilic bacterial strain TM-1 was isolated from the reservoir of the Shengli oil field in East China. Strain TM-1, which was found to be able to degrade crude oils, is a gram-positive non-motile bacterium with a coccus shape that can grow at temperatures of up to 58 °C and in 18% NaCl solution. Depending on the culture conditions, the organism may occur in tetrads. In addition, strain TM-1 produced acid from glucose without gas formation and was catalase-negative. Furthermore, strain TM-1 was found to be a facultative aerobe capable of growth under anaerobic conditions. Moreover, it produced butylated hydroxytoluene, 1,2-benzenedicarboxylic acid-bis ester and dibutyl phthalate and could use different organic substrates. Laboratory studies indicated that strain TM-1 affected different heavy oils by degrading various components and by changing the chemical properties of the oils. In addition, growth of the bacterium in heavy oils resulted in the loss of aromatic hydrocarbons, resins and asphaltenes, and enrichment with light hydrocarbons and an overall redistribution of these hydrocarbons.

关键词： Halophilic bacterium Metabolite Heavy oil Degradation

Microstructural and deformational studies on mylonite in the detachment faults of Yalashangbo dome, North Himalayan domes zone

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Progress in Natural science:Materials International 2005年第11期15卷 1005-1013页

作者： ZHANG Bo, ZHANG Jinjiang, GUO Lei and WANG Weiliang (Department of Geology, school of earth and space {3.s, peking university, beijing 100871, China) Department of Geology School of Earth and Space Sciences Peking University Beijing 100871 China

The Yalashangbo dome, located at the eastern end of North Himalayan domes zone, has a geometry and structure similar to those of a metamorphic core complex. Ductile shear zones formed the detachment system around the dome and these zones are composed of garnet-bearing phyllonite, mylonitic schist, mylonitic gneiss and mylonitic granite. Ductile shear fabrics developed well in my-lonitic rocks, and penetrative lineation and foliation were formed by stretched quartz and feldspar and preferred orientation of mica. Polar Mohr diagram method is used to calculate the kinematic vorticity numbers of the shear zones in the detachment system. Results indicate that the shear zone is a thinned shear zone (thinning of 23.% ) in an extensional setting which underwent a general shear dominated by simple shear. Comparison of the vorticity numbers between the northern and southern flanks of the Yalashangbo dome shows that the dome is an asymmetric system formed by a north-northwest-directed detaching unanimously. Statistical fractal analysis shows that the shapes of dynamically recrystallized quartz grains in the mylonites have characteristics of self-similarity, with fractal numbers ranging from 1.05 to 1.18. From these fractal numbers, the strain rate of the rock was deduced from 10-9.2S-1 to 10-7.3.-1, the differential paleao-stress was 13.7-25.6 MPa during the deformation happened at a temperature over 500 ℃. The ductile shear zones in the detachment system around Yalashangbo dome were formed under a high green-schist grade condition or happened simultaneously with the intrusion of granite.

关键词： Yalashangbo dome ductile shear zone kinematic vorticity fractal analysis deformation temperature strain rate.

Petrogenesis and significance of the Hongshan syenitic pluton,South Taihang: zircon SHRIMP U-Pb age, chemical compositions and Sr-Nd isotopes

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Progress in Natural science:Materials International 2006年第2期16卷 192-200页

作者： ZHOU Ling and CHEN Bin (Key Laboratory of Orogenic Belts and Crustal Evolution, MOE, school of earth and space {3.s, peking university, beijing 100871, China) [a]Key Laboratory of Orogenic Belts and Crustal Evolution MOE School of Earth and Space Sciences Peking University Beijing China

The Hongshan syenitic pluton (South Taihang) is mainly made up of hornblende syenite and minor granite. SHRIMP zircon dating yields a U-Pb age of 13.±2.7 Ma for the emplacement of the pluton, while biotite Rb-Sr isotopic data give an isochron of 120. 3.2.4 Ma. Hongshan syenites show low silica, high alkalis and LILE such as Sr, and exhibit negligible Eu anomalies or slightly positive anomalies in the REE patterns. The syenites show quite enriched isotopic compositions with Isr from 0.7052 to 0. 7102 and εNd(t) from -7.5 to - 11.1. Petrogenesis of the pluton can be that partial melting of an enriched lithospheric mantle gave birth to an alkali basaltic magma, which subsequently underplated in the lower crust and experienced a coupled fractionation of ferromagnesian phases like pyroxene and hornblende and minor (<10 %) contamination of lower continental crust, producing the Hongshan syenites that partially e-volved into granite through combined fractionation of hornblende and feldspar. Our data are not in agreement with a previous model that the syenites originated from melting of lower crust in a thickened crust circumstance, and thus do not support the speculation of "East China Plateau" in the Mesozoic.

关键词： syenite zircon SHRIMP Nd-Sr isotopes Taihang North China craton.

Effect of upward ion on field-aligned currents in the near-earth magnetotail

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science China(Physics,Mechanics & Astronomy) 2007年第5期50卷 673-680页

作者： ZHANG LingQian1, LIU ZhenXing1, MA ZhiWei2, SHEN Chao1, ZHOU XuZhi3.& ZHANG XianGuo3.1 Center for space and Applied Research, Chinese Academy of sciences, beijing 100080, China 2 Institute of Plasma Physics, Chinese Academy of sciences, Hefei 23.03., China 3.school of earth and space science, peking university, beijing 100871, China 1. Center for space and Applied Research Chinese Academy of Sciences Beijing 100080 China 2. Institute of Plasma Physics Chinese Academy of Sciences Hefei 230031 China 3. school of earth and space {3. Peking University Beijing 100871 China

A 3.dimensional resistive MHD simulation was carried out to study the effect of the upward ions on the field-aligned currents (FACs) in the near-earth magnetotail. The simulation results show that the up-flow ions originating from the nightside auroral oval would drift into the center plasma sheet along the magnetic field lines in the plasma sheet boundary, and have an important effect on the field-aligned currents. The main conclusions include that: 1) the upward-ions mainly affect the field- aligned currents in the near-earth magnetotail (inside 15 Re); 2) the generated FACs in the near-earth region have two types, i.e., Region 1 FAC in the high-latitude and Region 2 FAC in the low-latitude; 3. FACs increase with the enhancement of the upward ion flux; 4) with the same flux of the upward ions, FACs enhance with the increase of the velocity of the up-flow ions; 5) the intensification of FACs is also closely related with the latitude of the upward ions, and the ions from the closed field line region generate larger FACs; 6) the generation of FACs is closely related with By created by the upward ions.

关键词： up-flow ions, near-earth magnetotail, field-aligned current

Experimental measurement of growth patterns on fossil corals:Secular variation in ancient earth-Sun distances

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Chinese science Bulletin 2010年第35期55卷 4010-4017页

作者： ZHANG WeiJia1,3.4,LI ZhengBin2,3.& LEI Yang1 1 Department of Physics,peking university,beijing {3.,China 2 Department of Electrical Engineering and Computer science,peking university,beijing {3.,China 3.State Key Laboratory of Advanced Optical Communication Systems & Networks,peking university,beijing {3.,China 4 Committee of Yuanpei Honors Program,peking university,beijing {3.,China Department of Physics Peking University Beijing 100871 China State Key Laboratory of Advanced Optical Communication Systems & Networks Peking University Beijing 100871 China Committee of Yuanpei Honors Program Peking University Beijing 100871 China Department of Electrical Engineering and Computer science Peking University Beijing 100871 China

In recent years,much attention has been given to the increase in the earth-Sun distance,with the modern rate reported as 5-15 m/cy on the basis of astronomical ***,traditional methods cannot measure the ancient leaving rates,so a myriad of research attempting to provide explanations were met with unmatched *** this paper we consider that the growth patterns on fossils could reflect the ancient earth-Sun *** mechanical analysis of both the earth-Sun and earth-Moon systems,these patterns confirmed an increase in the earth-Sun *** a large number of well-preserved specimens and new technology available,both the modern and ancient leaving rates could be measured with high precision,and it was found that the earth has been leaving the Sun over the past 0.53.billion *** earth's semi-major axis was 146 million kilometers at the beginning of the Phanerozoic Eon,equating to 97.6% of its current *** modern leaving rates are 5-14 m/cy,whereas the ancient rates were much *** results indicate a special expansion with an average expansion coefficient of 0.57H0 and deceleration in the form of Hubble *** the basis of experimental results,the earth's semi-major axis could be represented by a simple formula that matches fossil measurements.

关键词：地球太阳古代距离生长模式实验石珊瑚量化