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U-Pb dating of zircon from the bed parallel anatectic granitic intrusion in the Baoban group in Hainan Island and the tectonic implication

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Science China Earth sciences 2005年第12期48卷 2092-2103页

作者： DING Shijiang1. HU Jianmin2, SONG Biao3,4, CHEN Mulun1. XIE Shengzhou1.& FAN Yuan1.1. Geological Surveying institute of Hainan, Haikou 570206, China 2. institute of Geomechanics, chinese academy of Geological sciences, beijing 1.0081. China 3. beijing center of SHRIMP, beijing 1.0037, China 4. institute of Geology, chinese academy of Geological sciences, beijing 1.0037, China 1. Geological Surveying institute of Hainan 570206 Haikou China 2. institute of Geomechanics Chinese Academy of Geological Sciences 100081 Beijing China 3. beijing{1. of SHRIMP 100037 Beijing China 4. institute of Geology Chinese Academy of Geological Sciences 100037 Beijing China

The petrological and geochemical features of the bed parallel granitic intrusion in the Pre-Cambrian Baoban group in Hainan Island attest to the anatexis origin of the granites. U-Pb dating analyses of zircons from the anatectic granite and the biotite two-feldspar gneiss in the Baoban group, using SHRIMP II in the beijing Ion-probe{1., acquire 206Pb/238U ages of 368±3.5 Ma (of granite, 95% confidence level, MSDW=1.23) and 362.9±6.1.Ma (of gneiss, 95% confidence level, MSDW = 2.04) respectively. The two late Devonian ages indicate consistently a tectonic- thermal event experienced in Hainan Island, and are the first discovered record of the Devonian geological process in the district. This event possibly resulted from the deep ther-mal-dynamic process when the Gondwana continent began to break up in the Devonian period.

关键词： Hainan Island, Devonian period, anatectic granite, zircon SHRIMP U-Pb dating.

The correspondence between the concepts in description logics for contexts and formal concept analysis

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Science China(Information sciences) 2012年第5期55卷 1106-1122页

作者： MA Yue 1.2,SUI YueFei 1.& CAO CunGen 1.1.Key Laboratory of Intelligent Information Processing,institute of Computing Technology,{1. academy of sciences,beijing 1.01.0,China 2 Graduate University of chinese academy of sciences,beijing,China 1. Key Laboratory of Intelligent Information Processing Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Formal concept analysis (FCA) and description logic (DL) are meant to be formalizations of concepts.A formal concept in the former consists of its intent and extent,where the intent is the set of all the attributes shared by each object in the extent of the concept,and the extent is the set of all the objects sharing each property in the intent of the concept.A concept in the latter formalization is simply a concept name,the interpretation of which is a subset of a *** consider the correspondence between concepts in both formalizations,a multi-valued formal context must be represented both as a knowledge base and as a model of the DL for contexts,where concepts are decomposed into tuple concepts C,interpreted as a set of tuples and value concepts V,interpreted as a set of attribute-value *** show that there is a difference between the interpretation of concepts R.V /R.C and the Galois connection between the extent/intent of formal concepts in *** to the Galois connection,there should be concepts of the form + R.V and + R.C inter-preted in FCA,and hence the logical language L for DL is extended to be L + together with + as a constructor so that + R.V and + R.C are well-defined ***,according to the interpretation in DL there should be pseudo concepts in FCA so that the interpretation of concepts R.V /R.C is the extent/intent of pseudo *** correspondence between formal concepts and concepts in L +,and between pseudo concepts and concepts in L are presented in this paper.

关键词： description logic formal concept analysis concept attribute/role

Ecological rebuilding and land reclamation in surface mines in Shanxi Province, China

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Journal of Environmental sciences 2000年第4期12卷 486-497页

作者： MIAO Ze wei 1. BAI Zhong ke 2, GAO Lin 1.(1. Research center for Eco Environmental{1., chinese academy of sciences, beijing 1.0085, China E\|mail: miaozewei@*** 2. Department of Soil Science, Shanxi Agricultural University Taigu, 03 中科院生态环境研究中心北京 1 0 0 0 85 山西师范大学山西临汾 0 3 0 80 1

It is well known that the mining industry produces a large amount of derelict land, and causes pollution of water loss and soil erosion as well as other environmental damage in China. As land is under pressure in China, it is now policy to restore or reclaim land despoiled by mining, the aim being to develop sustainable and healthy arable land ecosystems. This paper outlines the principles and approaches of ecological restoration, which have been adopted in Shanxi Province with reference to three typical surface mines. In the research, the principles of ecological engineering and ecological succession are considered as the critical theories of ecological restoration in mine degraded land. Meanwhile, the paper made a comparative research on main links of ecological rebuilding in three surface mines in Shanxi Province, which include new land construction, treatment of toxic substances, control of soil erosion, fertility management, irrigation, ecological planning and the establishment of legislation systems. As the research demonstrated, for successful restoration, new land construction is the fundamental framework, but it must be integrated with ecological engineering including ecological planning, the control of soil erosion and vegetation establishment and ecosystem creation in order to optimise land productivity and soil fertility. In addition, the establishment of the legislation systems and organization of administration are also indispensable aspects of ecological rebuilding in mined land.

关键词： ecological restoration land reclamation open-pit mine

Simulating the transfer and fate of hexachlorocyclohexane in recent 50 years in beijing, China

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Science China Earth sciences 2005年第12期48卷 2203-2213页

作者： CAO Hongying1. LIANG Tao1.& TAO Shu2 1. institute of Geographical{1. and Natural Resources Research, chinese academy of sciences, beijing 1.01.1. China 2. Laboratory for Earth Surface Processes, Peking University, beijing 1.0871. China 1. institute of Geographical{1. and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Laboratory for Earth Surface Processes Peking University 100871 Beijing China

Taking beijing as a study area, a dynamic fugacity model was used to simulate the transfer and fate of technical HCHs according to the physic-chemical properties of the studying environment and HCH isomers. Dynamic changes of the transfer fluxes and concentrations of HCH isomers during 1.52―2003 were simulated and the model results suggest good agreement between the calculated and measured concentrations of HCH isomers. During 1.52―1.83, the average input and output amount of HCHs through agricultural application and degradation are 1.0 t and 1.0 t respectively. The dominant transfer processes of HCHs in the study area are air-soil deposition, soil erosion and soil-air diffusion, transfer fluxes of these processes are 80 t?a?1. 1. t?a?1.and 1. t?a?1. which account for 92% of total transfer fluxes of HCHs isomers. There were approximately 253t HCHs in all environmental compartments of the study area during this period and 97% of which existed in soil compartment. Air and water advection became the dominant input sources of HCHs after 1.84 when the application of technical HCHs was prohib-ited, concentration of HCHs quickly descended to a quite low level in several years. Total amount of HCHs isomers remaining in the study area environment now is less than 5% that before 1.83, and this percentage may descend to 0.5% after 20 years by prediction.

关键词： fugacity model, hexachlorocyclohexane, compartment, transfer flux, fate.

Two-dimensional Riemann problems of simplified Euler equation

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chinese Science Bulletin 1998年第6期43卷 441-444页

作者： YANG Xiaozhou 1.2 and HUANG Feimin+1.1. institute of Applied Mathematics,{1., beijing 1.0080, China 2. Department of Mathematics, Shantou University, Guangdong 51.063, China institute of Applied Mathematics Chinese Academy of Sciences Beijing China Department of Mathematics Shantou University Guangdong China

The two-dimensional Riemann problem of simplifed Euler equation is discussed, in which initial value contains two different constant states that are separated by a smooth curve. This problem is a natural description of realistic phenomena, but it is hard to study by conventional idea. So a new approach is proposed. Some new properties about two-dimensional rarefaction wave, shock wave and intermediate state of solutions are disclosed.

关键词： D Riemann problem implicit functions cylindrical surface pencil of cylindrical surface.

SiO/CNTs:A new anode composition for lithium-ion battery

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Science China chemistry 2009年第12期52卷 2047-2050页

作者： REN YuRong1.2,3?,QU MeiZhen1.& YU ZuoLong1.1.Chengdu institute of Organic{1.,chinese academy of sciences,Chengdu 61.041.China 2 College of{1.,Jilin Normal University,Siping 1.6000,China 3 Graduate University of chinese academy of sciences,beijing 1.0039,China 1. Chengdu institute of Organic{1. Chinese Academy of Sciences Chengdu 610041 China 2. College of chemistry Jilin Normal University Siping 136000 China 3. Graduate University of chinese academy of sciences Beijing 100039 China

A new anode composition SiO/CNTs (carbon nanotubes) has been prepared by chemical vapor deposition (CVD) method. The results of scanning electron microscopy (SEM) confirm that CNTs deposit on small SiO particles,form a cage,and enwrap SiO particles tightly. SiO/CNTs anode composition exhibits an initial discharge and charge capacity of 1.71.and 789 mAh/g,and maintains a reversible capacity of 500 mAh/g after 80 cycles. The improvement of the cyclic performance for SiO/CNTs composition is related to the maintaining of the electric network during cycling,which benefits from a tight contact between CNTs and SiO particles.

关键词： SiO/CNTs CVD composition anode Li-ion battery

SHRIMP zircon U-Pb geochronology of early Mesozoic felsic igneous rocks from the southern Lancangjiang and its tectonic implications

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Science China Earth sciences 2006年第10期49卷 1032-1042页

作者： PENG Touping1.2, WANG Yuejun1. FAN Weiming1. LIU Dunyi3, SHI Yuruo3 & MIAO Laicheng4 1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou{1. of Geochemistry, chinese academy of sciences, Guangzhou 51.640, China 2. Graduate University of chinese academy of sciences, beijing 1.0039, China 3. SHRIMP isotope Laboratory, chinese academy of Geological sciences, beijing 1.0037, China 4.{1. of Geology and Geophysics, chinese academy of sciences, beijing 1.0029, China Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Graduate University of chinese academy of sciences Beijing China SHRIMP isotope Laboratory Chinese Academy of Geological Sciences Beijing China institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

The SHRIMP zircon U-Pb geochronology of three typical samples, including two monzo nitic granites from the Lincang batholith and a rhyolite from the Manghuai Formation are presented in the southern Lancangjiang, western Yunnan Province. The analyses of zircons for the biotite monzonitic granites from the northern (02DX-1.7) and southern (20JH-1.) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 206Pb/238U ages of 229.4 ± 3.0 Ma and 230.4 ± 3.6 Ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02DX-95) from the Manghuai Formation give a weighted mean 206Pb/238U age of 231.0 ± 5.0 Ma. These data suggest that the igneous rocks from the Lincang granitic batholith and Manghuai Formation have a similar crystallized age. In combination with other data, it is inferred that both were generated at a narrow age span (~230 Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 206Pb/238U apparent age of 1.77±44 Ma is additionally obtained from one zircon from the biotite monzonitic granite (southern Lincang batholith), indicative of devel- opment of the early Proterozoic Yangtze basement in the region. These precisely geochronological data provide important constraints on better understanding the Paleozoic tectonic evolution of the Tethys, western Yunnan Province.

关键词： SHRIMP zircon U-Pb dating, Middle Triassic, Lincang granitic batholith, Manghuai Formation rhyolite, southern Lancangjiang.

A Facile Synthesis Route to 1.3-dichlorodisilazanes

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chinese Chemical Letters 2000年第9期11卷 765-766页

作者： Cai Hong XU Ning ZHOU Ze Min XIE center for Molecular Science,{1., the chinese academy of sciences, beijing 1.0080 Acad Sinica Inst Chem Ctr Mol Sci Beijing 100080 Peoples R China

A new 1.3-dichlorodisilazane, 1.3-dichloro-1.3-dimethyl-1.3-divinyldisilazane (DMDV), was prepared from the reaction of hexamethyldisilazane (MMN) and methylvinyldichlorosilane. And use the same method, 1.3-dichloro-1...

关键词： Silazanes synthesis dichlorodisilazanes

Climatic and environmental changes over the last millennium recorded in the Malan ice core from the northern Tibetan Plateau

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Science China Earth sciences 2006年第10期49卷 1079-1089页

作者： WANG Ninglian1.2, YAO Tandong2,1. PU Jianchen1. ZHANG Yongliang1.& SUN Weizhen1.1. Key Laboratory of Cryosphere and Environment, Cold and Arid Regions Environmental and Engineering Research institute,{1., Lanzhou 730000, China 2. institute of Tibetan Plateau Research,{1., beijing 1.0085, China 1. Key Laboratory of Cryosphere and Environment Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China 2. institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China

In this paper, climatic and environmental changes were reconstructed since 1.29A.D. based on the Malan ice core from Hol Xil, the northern Tibetan Plateau. The record of δ 1.O in the Malan ice core indicated that the warm-season air temperature variations displayed a general increase trend, the 20th-century warming was within the range of natural climate variability, and the warmest century was the 1.th century while the warmest decade was the 1.1.s, over the entire study period. The “Medieval Warm Epoch” and “Little Ice Age” were also reflected by the ice core record. The dust ratio in the Malan ice core is a good proxy for dust event frequency. The 870-year record of the dust ratio showed that dust events occurred much frequently in the 1.th century. Comparing the variations of δ 1.O and the dust ratio, it is found that there was a strong negative correlation between them on the time scales of 1.1.1.2 years. By analyses of all the climatic records of ice cores and tree rings from the northern Tibetan Plateau, it was revealed that dust events were more frequent in the cold and dry periods than in the warm and wet periods.

关键词： the Tibetan Plateau, the Malan ice core, climate changes, dust event frequency.