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Science china Earth sciences 2004年第9期47卷 794-803页

作者： ZHANG Yueqiao1, CHEN Wen2. 3.& YANG Nong1 1. institute of Geomechanics, Chinese Academy of Geological sciences, {2. 100081, china 2. institute of geology, Chinese Academy of Geological sciences, {2. 10003., china 3. institute of geology and Geophysics, Chinese Academy of sciences, beijing 10002., china institute of Geomechanics Chinese Academy of Geological Sciences Beijing China institute of geology Chinese Academy of Geological Sciences Beijing China institute of geology and Geophysics Chinese Academy of Sciences Beijing China

Based on field geological survey, structural measurements and classical Ar/Ar dating of mica, biotite and K-feldspar, we obtain cooling ages for Miocene left-lateral shear along the Xianshuihe fault zone. The results document two thermal events during the sinistral shear. The early event (12.10 Ma) corresponds to rapid cooling of the Zheduoshan granitic massif from above 700℃ to below 3.0℃. The late event (5-3.5 Ma) corresponds to cooling of granites intruded along the eastern side of the fault zone. These dating results provide important thermochronological constraint on the timing of late Cenozoic eastward extrusion of the Chuan-Dian Block in the SE Tibetan margin.

关键词： Xianshuihe fault zone, Zheduoshan granitic massif, sinistral shear deformation, 40Ar/3.Ar dating, late Cenozoic.

Discovery of immune related factors in Fenneropenaeus chinensis by annotation of ESTs

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Progress in Natural Science:Materials International 2004年第1期14卷 48-55页

作者： SHEN Yaoqing 1,2. , XIANG Jianhai 1*, WANG Bing 1,2. , LI Fuhua 1 and TONG Wei 3.1. Experimental Marine Biology Laboratory, institute of Oceanology, Chinese Academy of {3., Qingdao 2.6071,{2. 2. Graduate School of the Chinese Academy of {3., beijing 10003., china 3. Genomics & Bioinformatics institute, Chinese Academy of {3., beijing 1013.0, china) Chinese Acad Sci Inst Oceanol Expt Marine Biol Lab Qingdao 266071 Peoples R China Chinese Acad Sci Grad Sch Beijing 100039 Peoples R China Chinese Acad Sci Geonom & Bioinformat Inst Beijing 101300 Peoples R China

A total of 10446 expressed sequence tags (ESTs) are obtained by a large scale sequencing of a cDNA library from cephalothorax of adult Fenneropenaeus chinensis . An EST analysis platform was built up based on local computers and bioinformatic techniques were used to annotate these ESTs in order to promptly find possible functional genes, especially for immune related factors. About 4% of the ESTs show similarity to the coding sequences of such factors, including lectin, serine protease, serpin, lysozyme, etc. These ESTs provide a partial profile of the immune system in F. chinensis and useful information for further study on these genes.

关键词： Fenneropenaeus chinensis bioinformatics ESTs immune factors

Mineralogy and crystal structure determination of Mg-fillowite

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Science china Earth sciences 2005年第5期48卷 635-646页

作者： MA Zhesheng 1 , SHI Nicheng 1 & YE Danian 2.1. china University of Geosciences, {2. 100083. china 2. institute of geology, Chinese Academy of sciences, beijing 10002., china china University of Geosciences Beijing China institute of geology Chinese Academy of Sciences Beijing China

Accurate crystal structure determination of complex phosphate Mg-fillowite ? Na2.a(Mn4Mg2.e)7[PO4]6 has been finished. Mg-fillowite occurs in muscovite-pegmatite in the Altay area, Xinjiang, china. It is of the trigonal lattice, with space group R-3. unit cell a=1.5143.3. nm, c=4.3.91(2. nm, V=8.573. nm3. Z = 18. The R-factor of the determination accuracy is R (I > 2. ( I )) = 0.0776. The cationic polyhedra consist of two kinds of structural units: compound col- umn and screw column. In three-dimensional space, they are linked with each other through corner sharing or edge sharing to build the entire structure. There are 45 atoms in an asymmetric unit and 72. atoms in a unit cell. In terms of types and connection manners of the coordination polyhedra, the degree of complicity is rarely seen in all mineral crystal structures. Study of such a structure is significant for the classification of phosphate and the building rule of coordination polyhedra in a complex crystal structure.

关键词： Mg-fillowite, complex phosphate, crystal structure, coordination polyhedron.

Dehydration melting of solid amphibolite at 2.0 GPa: Effects of time and temperature

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Science china Earth sciences 2005年第8期48卷 1120-1133页

作者： ZHOU Wenge1, XIE Hongsen1, LIU Yonggang1, ZHENG Xiaogang1, ZHAO Zhidan2.& ZHOU Hui3.1. Laboratory of Material in the Earth’s Interior, institute of Geochemistry, Chinese Academy of sciences, Guiyang 550002.{2. 2. Department of geology,{2. University of Geosciences, beijing 100083.{2. 3. Department of geology, Peking University, beijing 100871,{2. Laboratory of Material in the Earth’s Interior Institute of Geochemistry Chinese Academy of Sciences Guiyang China Department of geology China University of Geosciences Beijing China Department of geology Peking University Beijing China

Two sets of dehydration-melting with a natural solid amphibolite, collected from North Himalayan structure zone, Tibet, have been carried out in multi-anvil apparatus at 2.0 GPa and 800―1000℃, for 12.2.0 h. One is keeping the pressure at 2.0 GPa and the annealing time of 12.h, changing the temperature (800―1000℃). The other is keeping the pressure at 2.0 GPa and temperature at 850℃, varying the annealing time (12.2.0 h). The products are inspected with microscope and electron probe. The results indicate that at 2.0 GPa, annealing time of 12.h, garnets, melts and clinopyroxenes occur in amphibolite gradually with increasing temperature and the chemical compositions of melt vary from tonalite to granodiorite, and then to tonalite. However, at 2.0 GPa and 850℃, with the annealing time increasing, the garnets, melts and cli-nopyroxenes also occur in amphibolite gradually and the chemical compositions of melt vary from tonalite to granodiorite. In both cases, melts interconnect with each other when the contents of melt are over the 5 vol.%. the viscosities of the melt produced in amphibolite at temperature higher than 850℃ are on a level with 104 Pa·s. The interconnected melt with such a viscosity may segregate from the source rock and form the magma over reasonable geological time. Therefore, it is believed that at the lower part of the overthickened crust, the tonlitic and grano-dioritic magma may be generated through the dehydration melting of amphibolite.

关键词： solid amphibolite, high pressure, high temperature, time, partial melting.

A new DNA algorithm to solve graph coloring problem

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Progress in Natural Science:Materials International 2007年第6期17卷 733-738页

作者： Jiang Xingpeng1, Li Yin2. Meng Ya3.and Meng Dazhi2.1. National Laboratory of Pattern Recognition,institute of Automation, Chinese Academy of {3., {2. 100080, china 2. College of Applied {3., {2. University of Technology, beijing 10002., china 3. School of Science, {2. institute of Technology, {2. 100081, china) National Laboratory of Pattern Recognition Institute of Automation Chinese Academy of Sciences Beijing 100080 China College of Applied sciences Beijing University of Technology Beijing 100022 China School of Science Beijing Institute of Technology Beijing 100081 China

Using a small quantity of DNA molecules and little experimental time to solve complex problems successfully is a goal of DNA computing. Some NP-hard problems have been solved by DNA computing with lower time complexity than conventional computing. However, this advantage often brings higher space complexity and needs a large number of DNA encoding molecules. One example is graph coloring problem. Current DNA algorithms need exponentially increasing DNA encoding strands with the growing of problem size. Here we propose a new DNA algorithm of graph coloring problem based on the proof of four-color theorem. This algorithm has good properties of needing a relatively small number of operations in polynomial time and needing a small number of DNA encoding molecules (we need only 6R DNA encoding molecules if the number of regions in a graph is R).

关键词： DNA computing NP-hard problem graph coloring problem.

The age of the plant fossil assemblage in the Liuqu Conglomerate of southern Tibet and its tectonic significance

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Progress in Natural Science:Materials International 2006年第1期16卷 55-64页

作者： FANG Aimin1, YAN Zhen1, LIU Xiaohan2. PAN Yusheng1, LI Jiliang1, YU Liangjun1, HUANG Feixing2.and TAO Junrong3.(1.Laboratory of Lithosphere Tectonic Evolution, institute of {3. and Geophysics, Chinese Academy of {2., beijing 10002., china 2. institute of Tibet Plateau Research, Chinese Academy of {2., beijing 100085, china 3. institute of Botany, Chinese A cademy of {2., beijing 100093. china) Laboratory of Lithosphere Tectonic Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China institute of Tibet Plateau Research Chinese Academy of Sciences Beijing 100085 China institute of Botany Chinese A-cademy of Sciences Beijing 100093 China

The Liuqu Conglomerate, situated to the south of Yarlung Tsangbo Suture Zone (YTSZ), is a suit of molasse formed in a foreland basin of the Himalayan orogenic belt after the collision between the two plates of the Indian and Eurasion, It is of great significance in constraining the younger limit time of the collision of the two plates and providing stratigraphic evidence to reveal the post-colli sional tectonic evolution and uplifting history of the Tibet plateau. However, the age of this molasse suit and its correlation to other synchronous strata distributed in southern Tibet have been in great disputes for a long time. Especially in recent years, argues on its ages are growing violently with the recognition of the great sedimentary tectonic significances of this molasse. During the field work carried out recently on this molasse suit, a lot of plant fossils were found preserved in fairly good conditions in the upper part of this strata, which is of great help in determining its age. By identification, the assemblage of the plant fossils belongs to a tropic to subtropic flora developed in the southern margin of the Northern Hemisphere supercontinent during the Middle to Later Eocene, which can provide good constraint on its formation age. This paper is to give a brief introduction of the plant assemblage and its age, and to discuss their tectonic significances.

关键词： Liuqu conglomerate plant fossils age Eocene Tectonic implications.

The species diversity of fusulinaceans and high-frequency sea-level changes in the Carboniferous-Permian boundary section at Xikou, Zhen'an County,Shaanxi Province, china

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Science china Earth sciences 2006年第7期49卷 673-683页

作者： ZHANG Haijun1, WANG Xunlian2. DING Lin1, XIA Guoying3.& WANG Lei2.1. institute of Tibetan Plateau Research, Chinese Academy of {3., {2. 100085, china 2. Faculty of Earth {3. and Mineral Resources, china University of Geo{3., {2. 100083. china 3. Tianjin institute of {13. and Mineral Resources, Tianjin 3.0170, china institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China Faculty of Earth sciences and Mineral Resources China University of Geosciences Beijing China Tianjin institute of geology and Mineral Resources Tianjin China

The study on the interrelation between sea-level changes and biodiversity with its evolu-tion has great significance for understanding the impact of global changes on organic evolution and exploring the inherent laws of life-environment coevolution in geological history. In this paper, the stratigraphic distribution of fusulinacean fauna in the Carboniferous-Permian boundary section at Xikou, Zhen’an County, Shaanxi Province, is analyzed quantitatively, and the relationship between the species diversity of fusulinaceans and relative sea-level changes is discussed. As a whole, the spe-cies numbers of fusulinacean fauna experience a rapid increase and an obvious decline in Xikou, Zhen’an County, from the Late Carboniferous to the Early Permian. There is a significant increase in species diversity around the Carboniferous-Permian boundary, which is one of the biggest bio-events of the fusulinacean fauna, and represents the radiation of Pseudoschwagerininae subfamily in the studied area. Integrated fusulinacean species diversity into sequence stratigraphic framework, de-tailed study suggests that the species diversity of the fusulinaceans is closely related to its relative stratigraphic location, and is essentially controlled by the sea-level changes, especially by the high-frequency sea-level changes. Generally, the species diversity of fusulinaceans is low, and the number of first and last appearance datum is small in the lower unit of high-frequency depositional cycle formed during the quick rise of the sea level; whereas the species diversity of fusulinaceans is high, and the number of first and last appearance datum is large in the upper unit of high-frequency cycle formed during the slow fall of the sea level. Within the third-order depositional sequence, the species diversity of the fusulinaceans at the first flooding surfaces and the maximum flooding surfaces is low, and it increases upward. The fusulinacean species diversity is low within the transgressive syst

关键词： fusulinaceans, species diversity, high-frequency cyclothem, sequence stratigraphy, sea-level changes, Carboniferous-Permian boundary, Zhen'an, Shaanxi.

Compression behavior of Zr_(41)Ti_(14)Cu_(12.5)Ni_(10)Be_(2..5) bulk metallic glass up to 2. GPa

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Science china(Physics,Mechanics & Astronomy) 2005年第3期48卷 319-324页

作者： LI Gong 1, 2., ZHAN Zaiji 2., LIU Jing 3., YUN Jinku 1 , SUN Liling 2., LIU Riping 1 , ZHANG Jun 2.& WANG Wenkui 1, 2.1. Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, china 2. Center for Condensed Matter Physics, institute of Physics, Chinese Academy of {2., beijing 100080, china 3. BSRF, institute of High Energy Physics, Chinese Academy of {2., beijing 10003., china Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao China Center for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing China BSRF Institute of High Energy Physics Chinese Academy of Sciences Beijing China

The compression of a Zr41Ti14Cu12.5Ni10Be2..5 bulk metallic glass (BMG) is investigated at room temperature up to 2. GPa using in-situ high pressure energy dispersive X-ray diffraction with a synchrotron radiation source. The pressure-induced structural relaxation is exhibited. It is found that below about 8 GPa, the existence of excess free volume contributes to the rapid structural relaxation, which gives rise to the rapid volumetric change, and the structural relaxation results in the structural stiffness under higher pressure.

关键词： bulk metallic glass, high pressure, structural relaxation, synchrotron radiation.

Comparison of eastern paleo-Tethyan ophiolites and its geodynamic significance--Evidence from Dur'ngoi ophiolite

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Science china Earth sciences 2004年第4期47卷 378-384页

作者： CHEN Liang1,2. SUN Yong1,2. PEI Xianzhi2. Feng Tao2.& Zhang Guowei2.1. Open Laboratory of Continental Dynamics, Ministry of Education, Northwest University, Xi抋n 710069, china 2. institute of geology and Geophysics, Chinese Academy of {2., beijing 10002., china Open Laboratory of Continental Dynamics Ministry of Education Northwest University Xi’an China institute of geology and Geophysics Chinese Academy of Sciences Beijing China

Nd-Pb isotopic geochemistry of metabasalt from Dur抧goi ophiolite, Qinghai Prov-ince, NW china reveals the presence of DMM mixing with EMII components in its upper mantle source, which is comparable with present Indian MORB. Comparisons indicate that the geo-chemistry, chronology and source characteristics of Dur抧goi ophiolite coincide with Pa-leo-tethyan ophiolites from 揝anjiang?area. Together with evidences from regional geology in adjacent areas, this study proves that independent paleo-tethyan basins evolved contemporarily, the dynamics of which is attributed to the interaction of mantle plume with over-riding lithosphere.

关键词： ophiolite, Paleo-Tethys, DUPAL anomaly, Indosinian movement.

Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,Shandong Province,china

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Science china Earth sciences 2006年第1期49卷 77-87页

作者： MA Jinlong1,2. TAO Mingxin2.3.& YE Xianren2.1. Resources and Environmental School, Lanzhou University, Lanzhou 73.000,{3. 2. Key Laboratory of Gas Geochemistry, institute of {2. and Geophysics, Chinese Academy of sciences, Lanzhou 73.000,{3. 3. College of Resources Science & Technology, beijing Normal University, beijing 100875,{3. Resources and Environmental School Lanzhou University Lanzhou China Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou China College of Resources Science & Technology Beijing Normal University Beijing China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, Shandong Province, china, were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_2. CO and H_2. which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of eastern{3.; ratios of ~3.e/~4He in almost all samples range from 0.82.Ra to 2.74 Ra, whereas^(40)Ar/^(3.)Ar from 2.9.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~3.e range from 2..6 x 10~9 to 1050 x 10~9,N_2.Ar from 92. to 56612. and N_2.~3.e from 2.5 x 10~9 to 2. x 10~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.