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中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： Neng Jiang~(a,*),Jinghui Guo~a,Mingguo Zhai~a,Shuangquan Zhang~b a Key Laboratory of Mineral Resources,Institute of Geology and Geophysics,chinese academy of sciences,beijing,china b Department of Chemistry and Biochemistry,university of Windsor,ON,Canada

Numerous U-Pb zircon geochronological data show that rocks of the Precambrian basement from the North china craton(NCC)have two age peaks at 1.8-1.9 and～2.5Ga,*** the most prominent peak at～2.5 Ga really registered a period of major crustal growth in the NCC thus making it different from the global major crustal growth period of～2.7 Ga is *** this paper,we carried out in situ U-Pb and Hf isotopes of zircons and whole rock chemical and Sr-Nd isotopic analyses for six Precambrian samples from the NCC in order to understand crustal growth and *** samples have U-Pb zircon ages of 1.8-1.9,～2.5 and～2.7Ga,*** two samples with U-Pb zircon ages of～2.7 Ga have zircon Hf model ages(T)and/or whole rock Nd model ages(T)close to their U-Pb zircon *** is clear that they represent juvenile crust generation,thus providing direct evidence that～2.7 Ga was a period of new crustal *** samples with U-Pb zircon ages of～1.8 and～2.5 Ga also have Tand/or Tsimilar to those of the～2.7 Ga samples,indicating that these samples also have a mantle extraction time of 2.7±0.1 Ga and their～1.8 and～2.5 Ga ages may represent periods of reworking of the 2.7±0.1-Ga crust rather than juvenile crust *** reworking is manifested either as metamorphism or as lower crustal-derived ***,the～2.5-Ga tonalitic gneiss sample is thought to be derived by melting of the～2.7 Ga lower *** many～2.5- Ga tonalite-trondhjemite-granodiorites(TTGs)and calc-alkaline granitoids in the NCC contain～2.7-Ga xenocrystic and inherited zircons,we postulate that they are probably also derived mainly from the 2.7±0.1-Ga *** data imply that the quantity of～2.7 Ga continental crust in the NCC is probably greater in extent than that exposed today.

关键词： Crustal growth Crustal reworking North china craton U-Pb zircon ages Archean TTGs

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基于遥感技术的三峡库区土壤侵蚀量评估及影响因子分析

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山地学报 2011年第3期29卷 306-311页

作者：范建容刘飞郭芬芬张怀珍中国科学院水利部成都山地灾害与环境研究所中国科学院研究生院

基于遥感和地理信息系统技术,利用修正通用土壤流失方程对三峡库区的土壤侵蚀进行定量评估,并进一步分别利用MOD IS、TRMM遥感数据对其变化影响的主要因子植被覆盖和降雨侵蚀力变化进行了分析。结果表明:2005年土壤侵蚀总量为11 979.19... 详细信息

基于遥感和地理信息系统技术,利用修正通用土壤流失方程对三峡库区的土壤侵蚀进行定量评估,并进一步分别利用MOD IS、TRMM遥感数据对其变化影响的主要因子植被覆盖和降雨侵蚀力变化进行了分析。结果表明:2005年土壤侵蚀总量为11 979.19×104t,平均土壤侵蚀模数为2 087 t/(km2.a),与2000年土壤侵蚀模数2 381 t/(km2.a)相比,减少了294 t/(km2.a)。库区东部长江两岸大部分地区植被出现增长趋势,位于研究区边缘附近植被变化不明显;库区降雨侵蚀力总体呈增加趋势,同时降雨侵蚀力年际变化存在较明显的空间差异性。

关键词：三峡库区土壤侵蚀量植被覆盖降雨侵蚀力

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伊乐藻(Elodea nuttallii)对高浓度氮磷营养盐的耐受性

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生态学杂志 2009年第12期28卷 2561-2566页

作者：王小冬秦伯强高光杨桂军王洪艳宋玉芝冯胜中国科学院南京地理与湖泊研究所湖泊与环境国家重点实验室南京210008 中国科学院研究生院北京100039 南京信息工程大学南京210044

通过5个相对恒定的TN、TP浓度梯度下伊乐藻(Elodea nuttallii)的生长实验,探讨了伊乐藻对高浓度氮磷营养盐的耐受性,比较了各营养盐浓度下水体的pH值、DO、浮游藻类叶绿素a和附着藻类叶绿素a以及伊乐藻的株高、湿质量、干质量和叶绿素a... 详细信息

通过5个相对恒定的TN、TP浓度梯度下伊乐藻(Elodea nuttallii)的生长实验,探讨了伊乐藻对高浓度氮磷营养盐的耐受性,比较了各营养盐浓度下水体的pH值、DO、浮游藻类叶绿素a和附着藻类叶绿素a以及伊乐藻的株高、湿质量、干质量和叶绿素a含量。结果表明:在实验条件下,伊乐藻能耐受TN=10mg·mL-1,TP=0.4mg·mL-1的胁迫,且在该营养盐水平下水体中没有出现大量的浮游藻类;而在TN=50mg·mL-1、TP=2mg·mL-1和TN=100mg·mL-1、TP=4mg·mL-1的高营养盐条件下,伊乐藻的生长受到了明显的抑制,同时水体中的浮游藻类明显增多,而附着藻类则明显减少;在高营养盐水平下,一方面水体中的某些营养盐可能对伊乐藻产生了直接伤害,另一方面水体中浮游藻类的增多,所导致的遮光作用也可能限制了其生长;对水体中营养盐的平均水平低于TN=10mg·mL-1,TP=0.4mg·mL-1的太湖而言,沉水植被的消亡可能不是由于氮磷营养盐所产生的直接伤害和胁迫。

关键词：营养盐胁迫伊乐藻生长耐受性

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Enrichment of arsenic,antimony,mercury,and thallium in a Late Permian anthracite from Xingren,Guizhou,Southwest china

Enrichment of arsenic,antimony,mercury,and thallium in a Lat...

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中国科学院地质与地球物理研究所2006学术年会

作者： Shifeng Dai~(a,b),Rongshu Zeng~c and Yuzhuang Sun~a a Key Laboratory of Resource Exploration Research of Hebei Province,Handan 056038,china b china university of Mining and Technology,Dl 1,Xueyuan Road,Haidian District,beijing 100083,china c Institute of Geology and Geophysics,chinese academy of sciences,beijing 100029,china

Mineralogy and geochemistry of nine Late Permian coal-seam channel samples (anthracite) from Xingren,Guizhou,Southwest china were *** showed that As,Sb, Hg,and Tl are significantly enriched in a Late Permian anthracite(sample XR-M1) in the study area,and their contents are as high as 2226μg/g,3860μg/g,12.1μg/g,and 7.5μg/g,respectively. However,the contents of the four elements in other coal-seam channel samples from Xingren, even the two channel samples(samples XR-M2 and XR-M3) that are from the same bed as sample XR-M1,are close to the ordinary coal average,indicating that these four elements varied greatly in different coal beds and different locations of the same bed,and such coals highly enriched in these hazardous elements are very local and *** main carrier of As,Sb,Hg,and Tl in sample XR-M1 is an epigenetic getchellite rather than syngenetic pyrite and clay minerals. Getchellite occurs only in the veined kaolinite of hydrothermal *** high As,Sb,Hg,and Tl in coal are derived from an arsenic- and antimony-rich hydrothermal fluid.

关键词： Coal Arsenic Antimony Merciiry Thallium Getchellite Guizhou china

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The mathematical equivalence property of photonic bandgaps in photonic crystals and electronic bandgaps in electronic crystals for 1D and 2D systems

The mathematical equivalence property of photonic bandgaps i...

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CCAST“光子晶体”研讨会

作者： Zhengbiao Ouyang and Jingzhen LiSolid State Photonics Laboratory, College of Scientific Researches and Developments, Shenzhen university, Shenzhen 518060, chinaDaozhong Zhang Optical Physics Laboratory, Institute of Physics, chinese academy of sciences, beijing 100080, china

＜正＞Starting from the Schr（?）dinger equation of electron waves and the Maxell‘s waveequation of photons,we find that the wave equation of electrons in electronic crystalsand that of s-polarized photons in photonic crystals in 1D and 2D systems haveexactly the same *** mathematical equivalence property of photonic bandgapsand electronic handgaps in 1D and 2D systems for s-polarized photons exists both for

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A regional environmental management information system for chinese EPA—the system analysis and design

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Journal of Environmental sciences 1989年第2期1卷 91-97页

作者： Situ Wei, Cheng Shengtong, Zhang Xin, Long Peixiang and Liu HongbinDepartment of Environmental Engineering,Tsinghau university,beijing,china

REMIS is one of key research projects sponsored by the central government. It is recommended to regional EPAs as a main tool of the environmental management. REMIS simulates the functions of the regional EPAs and aimed to improve their management level. The national environmental management information system will base on *** analysis is the kernel of the REMIS system analysis. Data and data flow analysis are used to support the functional *** on the functions of the local EPAs of eight provinces and 12 cities have been taken. The functions were carefully sorted. Modular design method was used in system analysis and system *** system analysis included functional analysis, data analysis and data flow analysis. The system design is based on the system analysis. HIPO diagram of each modular, data base structure, menu design, selection of hardware and software environment were the main items of the system design.

关键词： environment management information system system engineering environmental management database.

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动态系统理论与第二语言发展

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外语教学与研究 2011年第3期43卷 409-421,480-481页

作者：李兰霞北京大学对外汉语教育学院08级博士生北京市100871

近几年,国际应用语言学界三大期刊相继推出专刊,这有力地推动了动态系统理论的发展。DST之所以具有革命性意义,在于它不但在理念上超越传统科学尊奉的简化论(reductionism),直面复杂、动态的第二语言学习过程,而且发展出了相应的研究方... 详细信息

近几年,国际应用语言学界三大期刊相继推出专刊,这有力地推动了动态系统理论的发展。DST之所以具有革命性意义,在于它不但在理念上超越传统科学尊奉的简化论(reductionism),直面复杂、动态的第二语言学习过程,而且发展出了相应的研究方法和工具,使我们能从新的角度考察真实语言的变异性和复杂性。本文从理论和方法论两方面,介绍了DST的发展背景、核心概念及相关研究成果。

关键词：动态系统复杂性变异性

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The 'egalitarian' gene for the germ cells

The 'egalitarian' gene for the germ cells

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“细胞活动生命活力”——中国细胞生物学学会全体会员代表大会暨第十二次学术大会

作者： Qing Geng~(1,2),Shaowei Zhao~(1,2),Di Chen~(1,2),Lingjuan Shan~(1,2),and Zhaohui Wang~1 1.Key Laboratory of Molecular and Developmental Biology,Institute of Genetics and Developmental Biology,chinese academy of sciences.Datun Road,beijing 100101,P.R.china. 2.graduate School,chinese academy of sciences,19 Yuquan Road,beijing 100039,P.R.china.

In our clonal-analysis based EMS mutagenesis screen to identify the factors involved in the early stages of germ cell development in Drosophila,we isolated an interesting mutant *** led to a dramatic loss of germ cells when the mutant clones were generated within an otherwise heterozygous background, indicating a nonautonomous *** have designated the mutant as gll {germline loss) and narrowed down the disruption to 3 candidate *** possibility of general cell lethality is excluded,given that the mutant animal was homozygous viable with normal *** examined the male gonads carrying germline gll-l- clones and found that germ cell loss occurred between 2nd to 3rd instar larval *** present,we are tracking down the responsible gene and trying to reveal how gll contributes to the homeostasis of adult germline cells and elucidate the molecular mechanism underlying this intriguing phenotype.

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A Cl--regulated structural switch that controls proton sensitivity of acid-sensing ion channels

A Cl--regulated structural switch that controls proton sensi...

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中国神经科学学会第九届全国学术会议暨第五次会员代表大会

作者： Wei-Guang LI~(1,2),Zhu-Dan ZHANG~(1,2),Hui CAO~1,Tian-Le XU~(1,3,*) 1 Institute of Neuroscience and State Key Laboratory of Neuroscience,Shanghai Institutes for Biological sciences, chinese academy of sciences,Shanghai 200031 2 graduate School of chinese academy of sciences,Shanghai 200031,china 3 Institute of Medical sciences,Shanghai Jiaotong university,Shanghai 200025

Acid-sensing ion channel(ASIC) has a prominent role in tissue pH-sensing and neuronal signaling,and participates in various pathological *** the availability of structures for chicken ASIC1 subunit, obtaining mechanistic insight into the function of these highly dynamic channel proteins using static crystallographic information is *** a series of mutational,chemical and functional approaches,we found that the extracellular CI-binding module shown in crystals of ASIC1 constitutes an indispensable component for ASIC1a *** gluconate-substitution of natural CI-binding enhanced whereas engineering a permanent anion into the CI-binding module inhibited channel activity,suggesting an essential role of CI-regulated domain flexibility but not the absolute charge state created by bound anion in channel ***-comparable anion substitution(F, Br-,or I) revealed a CI-dependent modulation of proton sensing function,supporting a structural role of dynamic association and dissociation of CI ion in coordinating conformational transition associated with proton sensing. Furthermore,charge reversal and swap as well as mutant cycle analysis of alanine substitutions of two counter-charged residues(K311,E315) in the CI-binding module show that they electrostatically interacted and energetically coupled, underpinning a structural switch controlling proton sensitivity of ASIC1a channels.

关键词： acid-sensing ion channel channel gating salt bridge

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A Novel Method of Signal Enhancement Based on Modified FastICA Algorithm

A Novel Method of Signal Enhancement Based on Modified FastI...

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ICEMI'2005第七届国际电子测量与仪器学术会议

作者： Wu Lili1 Chen Yuquan1 Huang Pinggao2 Mao Yuru3 Zhang Baojun4 (1State Specialized Laboratory of Biomedical Sensors College of Biomedical Engineering and Instrument Science Zhejiang university Hangzhou 310027 PR china (2Guilin university of electronic Technology Guilin 541004 china) (3chinese Research academy of Environmental sciences beijing 100012 china) (4College of Computer Science Zhejiang university Hangzhou 310027 china)

Independent component analysis (ICA) has attracted much attention in the field of signal processing. A novel method of speech signal enhancement by using modified FastICA algorithm is presented in thi

关键词： Independent component analysis (ICA) modified FastICA algorithm signal enhancement Newton iteration.

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