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Application of backflush and micro-flow techniques to the analysis of C5—C13 hydrocarbons in crude oils and its geochemical significance

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Progress in Natural Science:Materials International 2007年第11期17卷 1382-1387页

作者： Wang Peirong1,2, Zhao Hong2,3, Xu Guanjun1,4, Zhu Cuishan2,3, Xiao Tingrong4, Zhang Min2,3 and Zhang Bin1,4(1. key laboratory of Petroleum Geochemistry, china National Petroleum Corporation, beijing 100083, china 2. Geochemistry Department of Yangtze University, Jingzhou 434023, china 3. key laboratory of Exploration Technologies for Oil and Gas resources, ministry of education, Yangtze University, Jingzhou 434023, china 4. Petroleum Geology Central laboratory, Research Institute of Petroleum Exploration and Development, Petrochina, beijing 100083, china) key laboratory of Petroleum Geochemistry China National Petroleum Corporation Beijing 100083 China Geochemistry Department of Yangtze University Jingzhou 434023 China key laboratory of Exploration Technologies for Oil and Gas resources Ministry of Education Yangtze University Jingzhou 434023 China Petroleum Geology Central laboratory Research Institute of Petroleum Exploration and Development PetroChina Beijing 100083 China

An Agilent 6890N GC equipped with both FID and Agilent 5975 MSD analyzer has been employed to analyze C5—C13 hydrocarbon fractions of crude oils. A technical combination of program temperature volatilizer injection, backflush and micro-flow controller afforded a fine separation of C5—C13 compounds on a PONA column with the heavy part of crude oils being cut off before entering the analytical column. Both GC-FID chromatogram and GC-MS mass chromatograms (MID and full scan) could be obtained at the same time. The retension time differences of nC6—nC13 alkanes between GC and TIC were in the range of 0.02—0.58 minutes. Totally 286 peaks have been assigned group compositions. Results on 8 typical oil samples from CNPC key laboratory Crude Oil Library showed that the characteristics of C6—C13 hydrocarbon group composition could be used in oil-oil correlation studies.

关键词： GC analysis GC/MS analysis backflush micro-flow controller light fraction in crude oil

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Magnetism induced by nonmagnetic dopants in zinc-blende SiC: First-principle calculations

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Science china(Physics,Mechanics & Astronomy) 2010年第1期53卷 1-10页

作者： LIU ZhaoQing & NI Jun Department of Physics and key laboratory of Atomic and Molecular Nanoscience (ministry of education), Tsinghua University, beijing 100084, china Tsinghua University Department of Physics and Key Laboratory of Atomic and Molecular Nanoscience (Ministry of Education) Beijing China (GRID:grid.12527.33) (ISNI:***)

Magnetism induced by the nonmagnetic dopants in the zinc-blende SiC (3C-SiC) is investigated by first-principle calculations. The atoms of the first 20 elements in the periodic table except inert gas are used to replace either Si or C atoms as dopants. We find that some nonmagnetic substitutional dopants (mainly the Group IA, Group IIA, Group IIIB, and Group VIIB elements) prefer the spin-polarized ground states with local magnetic moments. In general, the condition for obtaining the local magnetic moments and the magnetic ground state requires that the dopants are p-type and have large electronegativity difference from the neighboring host atoms. The magnetic moments can be tuned over a range between 1 μ B and 3 μ B by doping with the nonmagnetic elements. The nearest-neighbor exchange couplings J 0 between the local magnetic moments are quite large and the codoping method is proposed to increase the dopant concentration. These imply that the nonmagnetic doping in SiC may exhibit collective magnetism. Moreover, the Group IIA Mg and Ca atoms substituting the preferred Si atoms favor the ferromagnetic ground states with the half-metallic electronic properties, which suggests that Mg or Ca substitutional doping on the Si sites in SiC could be a potential route to fabricating the diluted magnetic semiconductors.

关键词： nonmagnetic dopant magnetism SiC diluted magnetic semiconductor first-principle calculation

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Science china Earth Sciences 2004年第10期47卷 896-911页

作者： ZHANG Changhou1,2, WU Ganguo1,2, WANG Genhou2, ZHANG Weijie2 & SONG Honglin2 1. key laboratory of Lithospheric Tectonics and Lithoprobing Technology, china University of Geosciences, ministry of education of china, beijing 100083, china 2. School of Earth Sciences and Mineral resources, china University of Geosciences, beijing 100083, china key laboratory of Lithospheric Tectonics and Lithoprobing Technology China University of Geosciences Ministry of Education of China Beijing China School of Earth Sciences and Mineral resources China University of Geosciences Beijing China

The northwest trending tectonic belt in the middle part of the Mesozoic intraplate Yanshan Orogenic Belt, northeast Hebei Province, is composed of thrusts, extensional faults, strike-slip faults and syntectonic sedimentations as well. The northeastward basement-involved major thrusting deformation occurred between 174Ma and 168MaBP and was followed by an intrusion of the granitic plutonic rocks. As a part of the post-thrusting extensional deformations a northwest extending volcano-sedimentation system of Late Jurassic and Early Cretaceous formed in the southwest side of the belt. These volcano-sedimentary sequences are divided into Tuchengzi Formation, Zhangjiakou Formation, Yixian Formation and Jiufotang Formation re- spectively. They are characterized by southeastward migration as a result of the increasing down-dip slip displacement along the major extensional fault toward the southeast of the belt. The provenance area of the Jiufotang Formation north to it experienced southwestward thrusting during and after its later sedimentation. The thrusting in this stage resulted in the formation of an asymmetric footwall syncline with vergence to SW in the Jiufotang Formation in the NE side of the basin. Finally a dextral strike-slip deformation occurred along the NW tectonic belt. The striking tectono-geomorphological features and present seismic activities along this belt indicate that it has been being active since Cenozoic era and is still in the active state at present. This northwest extending tectonic belt was following the same direction and location as the existing fault systems within the basement as revealed by former geological and geophysical studies. So it is reasonable to infer the Mesozoic deformation along this belt to be a result of reactivation of the basement structures in a favorable tectonic stress field. The reactivation of basement struc- tures might be taken as one of the mechanisms of intraplate deformation and orogeny.

关键词： Yanshan Orogenic Belt, northwest extending tectonic complex, thrust system, geochronology.

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Performance analysis and optimal design for well patterns in anisotropic formations

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Petroleum Science 2008年第3期5卷 251-257页

作者： Liu Yuetian key laboratory of Petroleum Engineering Ministry of Education China University of Petroleum Beijing 102249 China

The mechanism of the effects of anisotropic permeability on well patterns and reservoir development are investigated by coordinate transformation, fluid flow analysis, and reservoir development concepts. Anisotropy of permeability has reconstructive effects on well patterns. The originally designed flooding units are broken up, and new pattern units are made up of the wells that belong to different original units. The behavior possesses strong randomness, and leads to a complicated relationship among the injection and production wells, and unpredictable productivity of the formations. To prevent the break-up of well patterns, well lines should be either parallel or perpendicular to the maximum principal direction of the anisotropic permeability （i.e. the fracture direction）. To optimize the development effects ofanisotropic formations, the latitudinal and longitudinal well spacing of the well network are calculated from the principal values of the anisotropic permeability.

关键词： Fractured reservoir anisotropic permeability performance analysis well pattern design

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MAPK signal pathways in the regulation of cell proliferation in mammalian cells

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Cell Research 2002年第1期12卷 9-18页

作者： WEI ZHANG, Hui Tu LIU The key laboratory of Cell Proliferation and Regulation Biology of ministry of education, College of Life Sciences, beijing Normal University, beijing 100875, china 1The key laboratory of Cell Proliferation and Regulation Biology of ministry of education College of Life Sciences Beijing Normal University Beijing 100875 China 1The key laboratory of Cell Proliferation and Regulation Biology of ministry of education College of Life Sciences Beijing Normal University Beijing 100875 China

MAPK families play an important role in complex cellular programs like proliferation, differentiation, development, transformation, and apoptosis. At least three MAPI(families have been characterized: extracellular signal-regulated kinase (ERK), Jun kinase (JNK/SAPK) and p38 MAPK. The above effects are fulfilled by regulation of cell cycle engine and other cell proliferation related proteins. In this paper we discussed their functions and cooperation with other signal pathways in regulation of cell proliferation.

关键词： MAPK ER.K JNK/SPAK p38 cell proliferation cross-talk.

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Hopping control channel MAC protocol for opportunistic spectrum access networks

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The Journal of china Universities of Posts and Telecommunications 2010年第6期17卷 65-71页

作者： FU Jing-tuan,JI Hong,MAO Xu key laboratory of Universal Wireless Communications,ministry of education,beijing University of Posts and Telecommunications,beijing 100876,china key laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Opportunistic spectrum access （OSA） is considered as a promising approach to mitigate spectrum scarcity by allowing unlicensed users to exploit spectrum opportunities in licensed frequency bands. Derived from the existing channel-hopping multiple access （CHMA） protocol,we introduce a hopping control channel medium access control （MAC） protocol in the context of OSA networks. In our proposed protocol,all nodes in the network follow a common channel-hopping sequence; every frequency channel can be used as control channel and data channel. Considering primary users＇ occupancy of the channel,we use a primary user （PU） detection model to calculate the channel availability for unlicensed users＇ access. Then,a discrete Markov chain analytical model is applied to describe the channel states and deduce the system throughput. Through simulation,we present numerical results to demonstrate the throughput performance of our protocol and thus validate our work.

关键词： channel hopping MAC protocol OSA Markov chain

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Nd-doped barium titanate ceramics with various Ti/Ba ratios prepared by sol-gel method

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Science china Chemistry 2005年第z1期48卷 60-64页

作者： SHI Qizhen,CUI Bin,WANG Hui,TIAN Jing,CHANG Zhuguo & HOU Yudong Department of Chemistry,Northwest University,Shaanxi key laboratory of Physico-lnorganic Chemistry,Xi’an 710069,china key laboratory of Advanced Functional Materials of china education ministry,beijing University of Technology,beijing 100022,china Department of Chemistry Northwest University Shaanxi Key Laboratory of Physico-lnorganic Chemistry Xi’an China key laboratory of Advanced Functional Materials of china education ministry Beijing University of Technology Beijing China

The Nd-doped BaTiO3 nanocrystalline powders and ceramics with different Ti/Ba ratios were prepared by sol-gel method. Phases and microstructures of the Nd-doped BaTiO3based powders and ceramics were characterized by XRD, SEM and TEM methods. The results revealed that the powders synthesized by sol-gel method were nanometer scale (30-60 nm)and were mainly composed of cubic BaTiO3 with a small amount of BaCO3. After sintering at high temperature, both cubic BaTiO3 and BaCO3 were transformed into tetrahedron BaTiO3 *** dielectric properties of the ceramics were also determined and the influence of Ti/Ba ratio on the dielectric properties was discussed. The Tc did not change with the variation of Ti/Ba ratio,while the εmax increased firstly and then decreased. The excess TiO2 is benefit for the modification of ceramics' microstructure and dielectric properties.

关键词： sol-gel method, dielectric properties, nanometer materials, Nd-doped barium titanate, Ti/Ba mole ratio.

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Bandwidth allocation and admission control scheme based on Nash bargaining solution for WiMAX systems

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The Journal of china Universities of Posts and Telecommunications 2010年第2期17卷 53-58页

作者： CAI Dao-jin ,JI Hong,LI Xi key laboratory of Universal Wireless Communications,ministry of education,beijing University of Posts and Telecommunications,beijing 100876,china key laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Development of fair and efficient bandwidth allocation and admission control schemes is one of the key issues in the design of IEEE 802.16 broadband wireless access systems in time division multiple access （TDMA） mode. In this article, the problem of bandwidth allocation and admission control is formulated as a Nash bargaining model. The nash bargaining solution （NBS） derived from the cooperative game is adopted to maximize the spectrum utilization. Analysis and simulation results show that there is a unique Pareto optimal bandwidth allocation solution by using NBS among various flows. Furthermore, maximum utility of the system can also be maintained by using the admission control policy with different number of connections and variable channel qualities. The total throughput of the proposed scheme is close to the maximal one, while significantly improving fairness compared to the existing solutions.

关键词： NBS game theory bandwidth allocation admission control IEEE 802.16

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End-Permian catastrophic event of marine acidification by hydrated sulfuric acid:Mineralogical evidence from Meishan Section of South china

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Chinese Science Bulletin 2002年第16期47卷 1393-1397页

作者： LIANG Handongkey laboratory of coal resources, china University of Mining and Technology, beijing 100083, china (e-mail: hdl6688@***) key laboratory of coal resources China University of Mining and Technology Beijing China

The event Permian-Triassic boundary (EPTB) is well marked by the famous 'white clay' of bed 25 in Mei-shan Section located in Changxing county, Zhejiang province of china. In this note, the white clay as well as its overlying and underlying sequences is investigated particularly for mineralogical records. The investigation yields three findings that contribute to better understanding the scenario of the EPTB mass extinction. (i) A red goethite-rich microlayer (0.3 mm) is first recognized to be horizontally widespread on the base of the white clay in the section. The microlayer should be considered as a macro geochemical indicator naturally tracing a catastrophic initiation at the EPTB. (ii) An interruption of marine carbonate deposition is discovered due to blank of carbonate minerals in the white clay. The discovery provides significant evidence of a marine acidification event that would occur in the paleo-ocean with marine acidity estimated at pH4.0 at least and be triggered by the ultimate

关键词： mass extinction marine acidification hydrated sulfuric acid Meishan Section goethite carbonate blank catastrophic event.

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Effects of chronic exposure to nonylphenol on locomotor activity and social behavior in zebrafish(Danio rerio)

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Journal of Environmental Sciences 2010年第9期22卷 1435-1440页

作者： Jigang Xia,Cuijuan Niu ,Xuejiao Pei ministry of education key laboratory of Biodiversity Science and Ecological Engineering,College of Life Sciences,beijing Normal University,100875 beijing,china. ministry of education key laboratory of Biodiversity Science and Ecological Engineering College of Life Sciences Beijing Normal University 100875 Beijing Chin

Nonylphenol （NP）, a xenoestrogen ubiquitously found in aquatic ecosystems, is of high environmental concern. The present work assessed the effects of exposure to NP on locomotor activity and social behavior in male and female zebrafish （Danio rerio）, to evaluate the possible hazard of NP to fish behavior and to pursue a potential biomarker of NP contamination. Fish were randomly divided into six groups. Five groups were receiving 0.1, 1, 10, 50 and 100 μg/L nominal concentrations of NP for 60 days, respectively. A sixth control group was given the same treatment as the other five groups, but no NP. Locomotor activity, aggressive behavior, group preference and leaving shoal were examined. NP exposure showed marked influence on locomotor activity of the male zebrafish, whereas that of the female was not significantly affected by NP. Aggressive behavior and group preference were significantly affected by NP exposure in both male and female groups. Locomotor activity and aggressive behavior of the male and group preference of both male and female zebrafish were clearly inhibited at 100 μg/L NP. No significant alteration in leaving shoal was observed under NP exposure. The results suggested that changes in locomotor activity and aggressive behavior of the male and group preference of both male and female may be used as an ecologically relevant integrative biomarker of NP contamination.

关键词： chronic toxicity nonylphenol biomarker zebrafish

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