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Hydrogen isotopic characteristics and their genetic relationships for individual n-alkanes in plants and sediments from Zoigê marsh sedimentary environment

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Science china Earth Sciences 2010年第9期53卷 1329-1334页

作者： DUAN Yi1, ZHENG ChaoYang2.& WU Baoxiang1 1 Key Laboratory of Petroleum Resources Research, Institute of geology and Geophysics, Chinese Academy of Sciences, Lanzhou 730000, china 2.2. of geology, Northwest University, xi’an 710069, china Key Laboratory of Petroleum Resources Research Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou China department of geology Northwest University Xi’an China

To understand internal relations of their hydrogen isotopic compositions in typical marsh environment, we, using GC-IRMS analytical technique, measured the hydrogen isotopes of individual n-alkanes in the herbaceous plant, woody plant leaf, and sediments from Zoigê marsh in china. The results show significant differences in the hydrogen isotopic compositions of n-alkanes among the different kinds of plants and the different species in the same kind. δD values of n-alkanes in the herbaceous plants (from -2.4‰ to -184‰) are lighter than those in woody plant leaf ( from -195‰ to -142. ), and the hydrogen isotopic compositions of n-alkanes in K. tibetica P. are lighter than P. pratensis L. The mean δD values of n-alkanes in the sediments from Zoigê marsh reflect that they were derived from herbaceous plants, which is consistent with the peat samples being composed mainly of herbaceous plant remnants. The significant differences in hydrogen isotopic compositions of n-alkanes among the sedimentary samples are caused possibly by environment factors and the difference in input quantity of different herbaceous plants. A certain negative correlation exists between the δ13C and δD values of n-alkanes in the samples, and plant types can be distinguished using the cross plot of δD vs. δ13C values of n-alkanes in the plants. These data and recognitions provide scientific basis for hydrogen isotopic applied research of individual n-alkanes.

关键词： marsh environment plants sediments individual lipids hydrogen isotopes genetic relationship

Geochronological evidence of Indosinian(high-pressure) metamorphic event and its tectonic significance in Taxkorgan area of the Western Kunlun Mountains,NW china

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Science china Earth Sciences 2010年第10期53卷 1445-1459页

作者： YANG WenQiang1,LIU Liang1,CAO YuTing1,WANG Chao1,2.HE ShiPing2.LI RongShe2.& ZHU xiaoHui1 1 State Key Laboratory of Continental Dynamics,department of geology,Northwest University,xi’an{2.,china 2.4} Institute of geology and Mineral Resource,xi’an 710054,china State Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi’an China xi’an Institute of geology and Mineral Resource Xi’an China

The CL images,LA-ICP-MS in situ trace elements analysis,and U-Pb dating for zircons indicate that the metamorphic ages of the sillimanite-garnet-biotite gneiss and the garnet-amphibole gneiss from eastern Taxkorgan of the Western Kunlun Mountains are 2.0±2.and 2.0±3 Ma respectively,and their protolith ages are younger than 2.3±2.and 480±8 Ma *** samples were collected at the same outcrops with HP mafic granulite and HP pelitic *** assemblage of the sillimanite-garnet-biotite gneiss(Grt+Sill+Per+Q) is consistent with that of HP pelitic granulite at early high amphibolite-granulite facies *** assemblage of the garnet-amphibole gneiss(Grt+Amp+Pl+Q) is consistent with retro-metamorphic assemblage of HP mafic granulite at amphibolite facies *** dating results suggest that these HP granulites underwent peak metamorphism at 2.0±2.to 2.3±2.***,the Kangxiwar tectonic zone was probably formed by subduction and collision of the Paleo-Tethys Ocean during *** ages of the two samples,together with previously published U-Pb zircon dating age,suggest that the sillimanite-garnet schist-quartzite unit is a late Paleozoic unit,not a part of the Paleoproterozoic Bulunkuole Group.

关键词： Western Kunlun Mountains LA-ICP-MS zircon dating Bulunkuole Group Indosinian Kangxiwar tectonic zone

Cartesian closedness of categories of completely distributive lattices

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Chinese Science Bulletin 1998年第24期43卷 2059-2063页

作者： ZHANG Dexue 1 and YANG Zhongqiang 2.1. department of Mathematics, Sichuan University, Chengdu 610064, china 2. department of Mathematics, Shaanxi Normal University, xi’an 710062. china department of Mathematics Sichuan University Chengdu China department of Mathematics Shaanxi Normal University Xi’an China

The category of completely distributive lattices with Scott continuous functions is cartesian closed. Neither the category of completely distributive lattices with arbitrary union preserving mappings nor the category ... 详细信息

关键词： completely distributive lattice continuous lattice cartesian closedness.

Essential natures of Carlin-type gold mineralization in the Zhenxun Basin

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Chinese Science Bulletin 1999年第S2期44卷 238-240页

作者： MA Jianqin~1 and ZHANG Fuxin~2.1. Institute of Geochemistry, Chinese Academy of Science, Guiyang 550002. china Present address: Highway Egineer College, xi’an Highway University, xi’an 710064, china 2. department of geology, Northwest University, xi’an, 710069, china Institute of Geochemistry Chinese Academy of Science Guiyang 550002 China Highway Egineer College Xi' an Highway University Xi' an 710064 China department of geology Northwest University Xi' an 710069 China

THE Zhen’ an-Xunyang (Zhen-Xun) Basin, located in the center of the Qinling Minor Plate in the Qinling orogen, develped and evoluted from the Devonian to the Triassic. The basin and its basement aresimilar to that of the southwestern part of the Yangtze Plate, where occur rich epithermal deposits. Thebasement of the basin is composed of the Proterozoic low-grade metamorphised volcanic and sedimentaryrocks, on which weakly metamorphised sedimentary and sedimentary rocks are deposited from the Cambrian to the Triassic. There occur three kinds of epithermal metal deposits: exhative-sedimentary-reformationtype Pb-Zn deposit (such as xitonggou and Yuexi) ; reformation type Hg-Sb deposit (such as Dingjiashanand Shijiashan) ; sedimentary-reformation type Au deposit (such as Jinlongshan, Qiuling, Yaojie andJiashigou). The Au deposits are associated with minor Sb deposit. This contribution demonstrates onlythe essential natures of the epithermal gold mineralization.

关键词： Carlin type gold mineralization Zhenxun Basin.

Synthesis,crystal structure and thermal behavior of Rb(NTO)·H_2.

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Chinese Science Bulletin 2001年第1期46卷 45-49页

作者： HU Mancheng, GAO Shiyang, LIU Zhihong, SONG Jirong, xiA Shuping & YU Kaibei1. Institute of Applied Chemistry, Shaanxi Normal University, xi’an 710062. china 2.{2. of Chemical Engineering, Northwest University, xi’an 710069, china 3. Chengdu Branch of Chinese Academy of Sciences, Chengdu 610041, china Institute of Applied Chemistry Shaanxi Normal University Xi’an China department of Chemical Engineering Northwest University Xi’an China Chengdu Branch of Chinese Academy of Sciences Chengdu China

The Rb(NTO) .H2. crystal has been synthesized by reaction of 3-nitro-l,2.4-triazole-5-one (NTO) with Rb2.O3 in aqueous solution. Its crystal structure has been determined. The crystal belongs to monoclinic system. Crystal structure data: space group P2./ n; a = 0.633 0(1), b = 0.82. 1(2., c =1.2.6 4(3) nm; β = 97.90(1)°; V = 0.669 9 (2. nm3, Z = 4, Dc= 2.306 g/cm3,μ = 7.365 nm-1, F(000) = 448. An eight coordinated compound is formed between Rb+ with oxygen atoms and nitrogen atoms. A layer structure is formed by coordination bonds and hydrogen bonds. The thermal decomposition mechanism of this coordination compound is discussed.

关键词： Rb-NTO coordination compound crystal structrue thermal decomposition.

Discovery of bipinnatifid fronds of Protoblechnum contractum(Gu et Zhi)

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Chinese Science Bulletin 1999年第4期44卷 381-383页

作者： SUN Bainian and SHEN Guanglong department of geology, Lanzhou University, Lanzhou 730000,{2. department of geology, Northwest University, xi’an 710069,{2. department of geology Lanzhou University Lanzhou China department of geology Northwest University Xi’an China

IN Permian floras of china, a dispute over the relationship among the Protoblechnum and other similar plants such as Compsopteris, Glenopteris and Supaia has been existing for a long time, and moreover it has not been completely solved up to now. Halle placed a few simple pinnate fronds from the Shihhotze Formation in the genus Protoblechnum and named them Protoblechnum Wongii Halle 70 years ago when he was studying the fossil plants from the Late Palaeozoic strata in Shanxi, china. He did not think forked or unforked fronds as an important dividing genus condition in discussing the distinction among Protoblechnum and other relative fossils. Zalessky alSO found some specimens similar to Chinese Protoblechnum while he studied the Permian fossil plants from Russia. However, he did not approve of

关键词： very over Discovery of bipinnatifid fronds of Protoblechnum contractum Gu et Zhi

Formation of the Permian basalts and implications of geochemical tracing for paleo-tectonic setting and regional tectonic background in the Turpan-Hami and Santanghu basins,xinjiang

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Science china Earth Sciences 2006年第6期49卷 584-596页

作者： ZHOU Dingwu1,2. LIU Yiqun1,2. xiNG xiujuan1, HAO Jianrong1, DONG Yunpeng1 & OUYANG Zhengjian1 1. Key Laboratory of Continental Dynamics, Ministry of Education, Northwest University department of geology, Northwest University,{2. 710069, china 2. Geoinformation Science & Engineering College, SDUST, Qingdao 2.6510, china Key Laboratory of Continental Dynamics Ministry of Education Northwest University Xi’an China Geoinformation Science & Engineering College SDUST Qingdao China department of geology Northwest University Xi’an China

The Turpan-Hami and Santanghu basins are the late Paleozoic-Mesozoic-Cenozoicreworked intracontinental basins that superposed on the folded basement of the Paleozoic orogenicbelt. ^(40)Ar/^(39)Ar geochronological study of the basalts developed in the basins reveals that theformation period is Permain (2.3—2.6 Ma). From geochemical comparison of the basalts, theSantanghu basalts exhibit a strong depletion in Nb and Ta, and a selective enrichment in HFSE,reflecting that the source region is influenced by the subducted components related to subduction ofthe ancient oceanic crust and characterized with ''lagged arc volcanic rocks''. In contrast, theTurpan-Hami basalts show a slight depletion in Nb and Ta, high Th/Ta ratio, similar to the basaltsformed in an intracontinental ex-tensional zone or in an initial rift. Combined with the formationperiod of the ophiolite and ophiolite melange zones and regional magmatic activities occurring onthe post-orogenic extensional background in northern xinjiang, it can be inferred from thesegeochemical characteristics that the tectonic background for forming the Turpan-Hami and Santanghubasins is closely related to the regional extension after the continent-continent collisionalorogeny. The basalts of the two basins came from different sources on the post-orogenic extensionalbackground of the similar basin-forming dynamics. Although the settings are all intracontinentalrift, the source for the Santanghu basalts is obviously subjected to the metasomatism of thesubducted components, implying the existence of the previous subduction.

关键词： xinjiang, Tu-Ha basin, Santanghu basin, basalt, postorogeny, tectonic setting, extensional background.

Preliminary notes on soft-bodied fossil concentrations from the Early Cambrian Chengjiang deposits

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Science Bulletin 2006年第20期51卷 2482-2492页

作者： HAN Jian1, SHU Degan1,2. ZHANG Zhifei1, LIU Jianni1, ZHANG xingliang1 & YAO Yang1 1. department of geology and Key Laboratory for Continental Dynam- ics, Northwest University,{2. 710069, china 2. School of Earth Sciences and Resources, china University of Geo- sciences, Beijing 100083, china department of geology and Key Laboratory for Continental Dynamics Northwest University Xi''an 710069 China School of Earth Sciences and Resources China University of Geo-sciences Beijing 100083 China

The efforts of labor-intensive collecting in the Early Cambrian Chengjiang deposits in eastern Yunnan Province, china led to the discovery of many horizons containing exceptionally well preserved soft-bodied fossil concentrations, many of which can be assigned to either monospecific concentrations or paucispecific concentrations. The features of these fossil concentrations support the hypothesis that frequent storm events producing tempestites mainly contributed to the preservation of abundant soft- bodied fossils in the Chengjiang deposits, and indi- cate that the balance of the ecological web in this region was probably frequently destroyed or upset by such storm events during that geological time. Ani- mals in a fossil assemblage in such fossil concentra- tions probably occupied similar ecological biotopes.

关键词： Early Cambrian Chengjiang fauna preservation soft- bodied fossil concentration (SFC).

Mathematic Expression of Kinetic Compensation Effect and Relationship between the Exothermic Decomposition Temperature and Critical Temperature of Thermal Explosion of Eighty-six Energetic Materials

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含能材料 2001年第1期9卷 8-9页

作者： HU Rong zu 1, YANG De suo 2. ZHANG Jiao qiang 3 (1. department of Chemistry,Northwest University, xi′an 710065, china 2. department of Chemistry and Chemical Engineering, Baoji College of Arts and Science, Baoji 72.007, china 3. department of 西北大学陕西西安 710065 宝鸡文理学院陕西 721007 西北工业大学陕西西安 710072

Two relationships are established using the least squares method,between the kinetic parameters (the apparent activation energy and pre exponential constant),and the exothermic decomposition temperature and ther... 详细信息

关键词： critical temperature of thermal explosion decomposition temperature DSC energetic materials.