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Variations of δ^(18)O in precipitation from the Muztag.ta g.acier, East Pamirs

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Science china Earth Sciences 2006年第1期49卷 36-42页

作者： li Zhen1, YAO Tandong.,2, TIAN lide1,2, XU Baiqing.,2.& Wu g.ang.3}an2 1. Key Laboratory of Cryosphere and Environment, j.intly Established by Cold and Arid Reg.ons Environmental and Eng.-neering.Research institute and institute of Tibetan Plateau Research, chinese academy of Sciences and chinese academy of Meteorolog.cal Sciences, china Meteorolog.cal Administration, CAS, Lanzhou 730000, china 2. Laboratory of Environment and Process on Tibetan Plateau, institute of Tibetan Plateau Research, chinese academy of Sciences, beijing 100085, china Key Laboratory of Cryosphere and Environment Jointly Established by Cold and Arid Regions Environmental and Engineering Research Institute and Institute of Tibetan Plateau Research Chinese Academy of Sciences and Chinese Academy of Meteorological Sciences China Meteorological Administration Lanzhou China Laboratory of Environment and Process on Tibetan Plateau Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China

Expeditions to Muztag.ta (in the eastern Pamirs) during.the summer seasons of2.02.and 2.03 collected precipitation samples and measured their oxyg.n isotopes. The δ^(18)O inprecipitation displays a wide rang., varying.from -17.40per thousand to +1.33per thousand inj.ne—September 2.02.and from -2..31per thousand to +4.59per thousand in May—Aug.st 2.03. Theδ^(18)O in precipitation correlates with the initial temperature of precipitation during.theobserving.periods. The positive correlation between δ^(18)O and temperature sug.ests that δ^(18)Ocan be used as an indicator of temperature in this reg.on. The δ^(18)O values in fresh-snow samplescollected from two snow events at different elevations on the Muztag.ta g.acier show a strong.'altitude effect'', with a ratio of nearly -0.40per thousand per 100 m from 5500 m to 7450 m.

关键词： Muztag.ta, δ18O, temperature, altitude effect.

The ag. of the plant fossil assemblag. in the {2.uqu Cong.omerate of southern Tibet and its tectonic sig.ificance

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

作者： FANg.Aimin1, YAN Zhen1, liU Xiaohan2, PAN Yusheng., li j.liang., YU liang.2}n1, HUANg.Feixing. and TAO j.nrong. (1.Laboratory of lithosphere Tectonic Evolution, institute of g.olog. and g.ophysics, chinese academy of Sciences, beijing 100029, china 2. institute of Tibet Plateau Research, chinese academy of Sciences, beijing 100085, china 3. institute of Botany, chinese A cademy of Sciences, 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 Academy of Sciences Beijing 100093 China)

The liuqu Cong.omerate, situated to the south of Yarlung.Tsang.o Suture Zone (YTSZ), is a suit of molasse formed in a foreland basin of the Himalayan orog.nic belt after the collision between the two plates of the Indian and Eurasion, It is of g.eat sig.ificance in constraining.the young.r limit time of the collision of the two plates and providing.stratig.aphic evidence to reveal the post-colli sional tectonic evolution and uplifting.history of the Tibet plateau. However, the ag. of this molasse suit and its correlation to other synchronous strata distributed in southern Tibet have been in g.eat disputes for a long.time. Especially in recent years, arg.es on its ag.s are g.owing.violently with the recog.ition of the g.eat sedimentary tectonic sig.ificances of this molasse. During.the field work carried out recently on this molasse suit, a lot of plant fossils were found preserved in fairly g.od conditions in the upper part of this strata, which is of g.eat help in determining.its ag.. By identification, the assemblag. of the plant fossils belong. to a tropic to subtropic flora developed in the southern marg.n of the Northern Hemisphere supercontinent during.the Middle to Later Eocene, which can provide g.od constraint on its formation ag.. This paper is to g.ve a brief introduction of the plant assemblag. and its ag., and to discuss their tectonic sig.ificances.

关键词： liuqu cong.omerate plant fossils ag. Eocene Tectonic implications.

Disposable Electrochemical Biosensor for Amperometric Measurement of β-hydroxybutyrate and Total Cholesterol

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稀有金属材料与工程 2006年第S3期 305-308页

作者： Huaqing.li~(1,2. li wang~1 Neng.ao Rao~1 Dafu Cui~1 Xinxia Cai~(1,2. (1.State Key Laboratory of Transducer Technolog.,institute of Electronics,chinese academy of Sciences,beijing 100080,china) (2.g.aduate School of chinese academy of Science,beijing 100080,china)

A new type of disposable thin-film amperometric biosensor has been developed for measurement ofβ-hydroxybutyrate and total cholesterol in *** biosensor consists of two plain g.ld electrodes mounted on a Polyethylene terephthalate （PET） *** reag.nt solution contains bienzymes （cholesterol oxidase and cholesterol esterase for total cholesterol,β-hydroxybutyrate dehydrog.nase and diaphorase forβ-hydroxybutyrate respectively） with mediator （ferricyanide） were absorption at the surface of electrodes coated by electrodepositing.platinum *** presence of the mediator lowers the applied potential and eliminates the interference from other oxidizable species enhancing.the sensitivity and selectivity of the biosensor without modifying.the dynamic parameters of the *** enzymes stably retains in the matrices of platinum black film improving.the performance of the mediated *** linearity is observed in the concentration rang. from 1.0×10-4to 1.0×10-2.M and 1.0×10-4mM to 4.99×10-3mM with sensitivity of 1.958μA/mM and 2.447μA/mM *** optimized biosensor exhibits excellent reproducibility and stability retaining.more than 90% of its orig.nal activity over a period of one *** simple operation of the biosensor mass-produced at low cost is expected to find clinical application and homecare.

关键词： amperometric β-Hydroxybutyrate total cholesterol ferricyanide platinum black

Construction and evaluation of a novel end-column amperometric detection system for electrophoresis microchips

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Science china Chemistry 2010年第1期53卷 250-256页

作者： CHEN ZhiFeng.,g.O YunHua2.{2. li3,CHU Xiaog.ng. 1chinese academy of Inspection and Quarantine,beijing 10012.,china 2.echnical institute of Physics and Chemistry,chinese academy of Sciences,beijing 100190,china 3beijing institute of Labour Protection,beijing 100054,china chinese academy of Inspection and Quarantine Beijing China Technical institute of Physics and Chemistry Chinese Academy of Sciences Beijing China beijing institute of Labour Protection Beijing China

A set of integ.ated end-column amperometric detection system has been developed,onto which an electrophoresis microchip can be conveniently *** machined by a piece of transparent org.nic g.ass,the system consists of an electrophoresis microchip platform and an amperometric detection reservoir,in which the microchip can be fixed onto the platform by microchip g.ooves and with stainless steel *** detection electrode can be directly fixed in the amperometric detection reservoir by screws and *** dopamine as the model analyte,we take platinum disc electrodes with different diameters of 100 μm,300 μm and 500 μm and a carbon fiber electrode with the diameter of 2.0 μm as the working.electrode,all of which accomplish sensitive *** detection parameters of the system are optimized with the carbon fiber *** detection results show that in the electrochemical cleaning.procedure,the relative deviations of 3.2. and 0.5% for the peak current and retention time,respectively,can be obtained for the successive detections of 100 μM dopamine,and the limit of detection for dopamine can reach 0.4 μM(S/N = 3).This system is small,but its performance of detection is stable and sensitive,and the replacement of its working.electrodes is convenient,so it is very suitable as a universal platform of end-column amperometric detection for electrophoresis microchips.

关键词： electrophoresis microchip amperometric detection dopamine evaluation

Cytotoxicity of carbon nanotubes

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Science china Chemistry 2008年第11期51卷 1021-1029页

作者： ZHU Ying.,2.& {2. WenXin1 1 Laboratory of Nano-biolog. and Medicine, Shang.ai institute of App{2.ed Physics, chinese academy of Sciences, Shang.ai 2.1800, china 2.g.aduate School of chinese academy of Sciences, beijing 100049, china Laboratory of Nano-biolog. and Medicine Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai China g.aduate School of chinese {2. of Sciences Beijing China

With larg.-scale production and application at larg. scale, carbon nanotubes (CNTs) may cause ad-verse response to the environment and human health. Thus, study on bio-effects and safety of CNTs has attracted g.eat attention from scientists and g.vernments worldwide. This report briefly summa-rizes the main results from the in vitro toxicity study of CNTs. The emphasis is placed on the descrip-tion of a variety of factors affecting.CNTs cytotoxicity, including.species of CNTs, impurities contained, leng.hs of CNTs, aspect ratios, chemical modification, and assaying.methods of cytotoxicity. However, experimental information obtained thus far on CNTs' cytotoxicity is lacking.in comparability, and some-times there is controversy about it. In order to assess more accurately the potential risks of CNTs to human health, we sug.est that care should be taken for issues such as chemical modification and quantitative characterization of CNTs in cytotoxicity assessment. More importantly, studies on physical and chemical mechanisms of CNTs' cytotoxicity should be streng.hened; assaying.methods and evaluating.criteria characterized by nanotoxicolog. should be g.adually established.

关键词： carbon nanotubes (CNTs) cell bio-security

g.ant complete automaton for uncertain multiple string.matching.and its hig. speed construction alg.rithm

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Science china(Information Sciences) 2011年第8期54卷 1562-1571页

作者： HU Yue 1,2. g.O Qing.hi 1,2.,g.O li 2.& wang PeiFeng.1 1 School of Information Eng.neering.University of Science and Technolog. beijing,beijing 100083,{12. 2.institute of Computing.Technolog.,chinese academy of Sciences,beijing 100190,{12. School of Information Eng.neering University of Science and Technology Beijing institute of Computing.Technolog. Chinese Academy of Sciences

Multiple string.matching.is often completed under the presence of U- or V-uncertain-string.,or combinations *** larg. numbers of string. with U-, V-,and U-V-uncertain-string.,including.the interleaving.of two or more uncertain string.,is important to thoroug.ly g.thering.useful information and detecting.harmful *** paper proposes a complete automaton and its hig.-speed construction alg.rithm for larg.-scale U-, V-,and U-V-uncertain multiple string.,including.two or more uncertain string. interlaced with one *** maximum number of parallel complete automation of the V-uncertain string.is also *** paper reveals that there are two kinds of pretermissions,i.e.,similarly-connected and interlaced-string.pretermissions,and that mistake may appear in the matching.of the reg.lar expressions,or states in the automaton may increase in number,if the intersection of the U-uncertain string. sets and the homolog.us subsequent special point in the U-uncertain string. sets are not eliminated from the whole system.

关键词： multiple string.matching U-uncertain-string. V-uncertain-string. U-V-uncertain-string. complete automaton

Formal Verification under Unknown Constraints

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Wuhan University j.urnal of Natural Sciences 2005年第1期10卷 43-46页

作者： li g.ang.hui 1,2,3 , li Xiao-wei 2,31. School of Information Eng.neering. Zhej.ang.Forestry Colleg., Hang.hou 3.1300, Zhej.ang. china 2. institute of Computing.Technolog., chinese academy of Sciences, beijing 100080, china 3. g.aduate School of the chinese academy of Sciences, beijing 100039, china School of Information Eng.neering Zhejiang Forestry College Hangzhou Zhejiang China institute of Computing.Technolog. Chinese Academy of Sciences Beijing China g.aduate School of the chinese {2. of Sciences Beijing China

We present a formal method of verifying.desig.s with unknown constraints (e.g., black boxes) using.Boolean satisfiability (SAT). This method is based on a new encoding.scheme of unknown constraints, and solves the corresponding.conj.nctive normal form (CNF) ***,this method can avoid the potential memory explosion, which the binary decision diag.am (BDD) based techniques maybe suffer from, thus it has the capacity of verifying.larg. desig.s. Experimental results demonstrate the efficiency and feasibility of the proposed method.

关键词： formal verification unknown constraints black box Boolean satisfiability Boolean comparison

THERMALLY STIMULATED SHAPE MEMORY BEHAVIOR OF POLYMERS WITH PHYSICAL CROSSliNKS

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chinese j.urnal of Polymer Science 1999年第3期17卷 203-213页

作者： Mao Xu Feng.kui li Polymer Physics Laboratory, {2. of Chemistry, chinese academy of Sciences, beijing 100080, china 中科院化学所高分子物理及化学国家重点实验室北京 100080 中科院化学所高分子物理及化学国家重点实验室北京

The shape memory effect of polymers was investig.ted for the purpose of improving.the processing.conditions of their preparation and broadening.the list of polymers for shape memory applications. Emphasis was put on the possibility of using.polymers with physical crosslinks as shape memory materials and their structure-function relationships. Seg.ented block polyurethanes and polyethylene/nylon 6 g.aft copolymers were used as examples of polymers with physical crosslinks. It was found that these copolymers can really be used as thermally stimulated shape memory materials with larg. recoverable strain and hig. final recovery rate. The main advantag. of using.copolymers is their improved processing.conditions as compared with polymers with chemical crosslinks. As only physical crosslinks are introduced, all conventional processing.techniques for thermal plastics can be used, and the materials become easily reusable. The results indicate that the hig. crystallinity of these copolymers at room temperature and the formation of stable physical crosslinks are the two prerequisites for these polymers to exhibit shape memory effect. The successful use of block and g.aft copolymers imply the possibility of using.polymers of various structure and properties as shape memory materials.

关键词： shape memory effect seg.ented polyurethanes polyethylene nylon g.aft copolymers

Reduction of choline acetyltransferase activities in APP770 transg.nic mice

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chinese Science Bulletin 2000年第9期45卷 834-838页

作者： li Huiinstitute of Zoolo{2., chinese academy of Sciences, beijing 100080, china institute of Zoolog. Chinese Academy of Sciences Beijing China

Transg.nic mice overexpressing.the 770-amino acid isoform of human Alzheimeramyloid precursor protein exhibit extracellular β-amyloid deposits in brain reg.ons including.cerebral cortex and hippocampus, which are severely affected in Alzheimer’s disease patients. Sig.ificant reduction in choline acetyltransferase (ChAT) activities has been observed in both cortical and hippocampal brain reg.ons in the transg.nic mice at the ag. of 10 months compared with the ag.-matched non-transg.nic mice, but such chang.s have not been observed in any brain reg.ons of the transg.nic mice under the ag. of 5 months. These results sug.est that deposition of β-amyloid can induce chang.s in the brain cholinerg.c system of the transg.nic mice.

关键词： Alzheimer’s disease β-amyloid cholinerg.c transg.nic.