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Eclogites in the interior of the Tibetan Plateau and their geodynamic implications

chinese science Bulletin 2009年第15期54卷 2556-2567页

作者： ZHANG KaiJun1,2 & TANG XianChun2,3 1 Department of Earth sciences, Nanjing university, Nanjing 210093, china 2 Guangzhou Institute of Geochemistry, chinese academy of sciences, Guangzhou 510640, china 3 graduate university of chinese academy of sciences, beijing 100049, china Department of Earth sciences Nanjing University Nanjing China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China graduate university of chinese academy of sciences Beijing China

Eclogites have been recently reported in the interior of the Tibetan Plateau, including in the central Qiangtang metamorphic belt, in the Basu metamorphic massif of the eastern Bangong-Nujiang suture zone, and at Songdo and Pengco in the eastern Lhasa terrane. Some typical ultrahigh-pressure (UHP) metamorphic phenomena, e.g., garnet exsolution from clinopyroxene, were documented in the Basu and Pengco eclogites. The UHP metamorphism in the interior of the Tibetan Plateau marked by these eclogites generally took place in the Early Mesozoic. Along with exhumation of these eclogites, (post-) collision-related magmatism extensively occurred around the central Qiangtang belt, the eastern Ban-gong-Nujiang suture zone, and the eastern Lhasa terrane. The occurrence of these Early Mesozoic ec-logites manifests an out-of-sequence evolution of the Tethys, and they could be a product of diachro-nous collision between the eastern Qiangtang terrane and the irregular continental margin of the united western Qiangtang-Lhasa plate, along the linked eastern Bangong-Nujiang-central Qiangtang zone. The collision-related magmatic rocks could have been originated from lithospheric thickening, melting, or detachment due to the collision. The presence of UHP metamorphic rocks in central Qiangtang and Basu implies likely continental deep-subduction, and the denudation of these two metamorphic zones could have served as the source of the Triassic turbidites in the Songpan-Garzê complex and the Ju-rassic turbidites in the western Bangong-Nujiang zone, respectively. However, studies of the eclogites in the interior of the Tibetan Plateau just began, and many principal aspects still remain to be explored, such as their distributions, typical lithologies and minerals, temperature-pressure conditions, timing of formation and exhumation, protoliths and tectonic setting, and relationship with the evolution of the Tethys and large-scale basins in Tibet.

关键词：地球动力学意义青藏高原榴辉岩

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An efficient chiral synthesis of (R)-N-[3-acetyl-4-(2-hydroxy-3-isopropylamino-propoxy)phenyl]-butanamide with high enantioselectivity

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science china Chemistry 2009年第8期52卷 1216-1219页

作者： WANG NaiXing1,2 & TANG XinLiang1,3 1 Technical Institute of Physics and Chemistry,chinese academy of sciences,beijing 100080,china 2 College of Chemistry and Chemical Engineering,graduate university of chinese academy of sciences,beijing 100049,china 3 School of Chemical Engineering and Environment,beijing Institute of Technology,beijing 100081,china Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing China College of Chemistry and Chemical Engineering Graduate University of Chinese Academy of Sciences Beijing China School of Chemical Engineering and Environment Beijing Institute of Technology Beijing China

R-Enantiomer of the β-receptor antagonist N-[3-acetyl-4-(2-hydroxy-3-isopropylamino-propoxy)phenyl] butanamide with high enantioselectivity was synthesized from cheap starting materials and enantiopure chiral reagent through an efficient,convenient and practical synthetic *** product was detected by 1H NMR,13C NMR,and MS,and the enatiomeric excess was determined by chiral HPLC analysis using a chiracel AD-H column.

关键词： chiral synthesis enantioselectivity enatiomeric excess chiral HPLC analysis

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cDNA cloning, expression and antibacterial activity of lysozyme C in the blue shrimp (Litopenaeus stylirostris)

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Progress in Natural science:Materials International 2009年第7期19卷 837-844页

作者： Weijun Mai a,b, Chaoqun Hu a, a Applied Marine Biology Laboratory, South china Sea Institute of Oceanology, science academy of china, Guangzhou 510301, china b graduate university of chinese academy of sciences, beijing 100049, china Applied Marine Biology Laboratory South China Sea Institute of Oceanology Science Academy of China Guangzhou 510301 China graduate university of chinese academy of sciences Beijing 100049 China

The gene coding for lysozyme in blue shrimp (Litopenaeus stylirostris) was cloned, sequenced and expressed in pET-32a vector. The deduced amino acid sequence of F. merguiensi lysozyme showed 37–93% similarity with the mouse, human, chicken, and tiger prawn counterparts. The lysozyme was purified to homogeneity and observed as a band of approximately 15 kDa in 15% SDS–PAGE. Semiquantitative RT-PCR analysis demonstrated that mRNA transcripts of lysozyme could be mainly detected in the tissues of haemocytes, gill, gonad and the lymphoid organ of unchallenged shrimps, whereas the expression of lysozyme transcripts was increased in all the tested tissues after the heat-killed Vibrio alginolyticus challenge. The temporal expression of lysozyme mRNA in haemolymph challenged by Micrococcus luteus and V. alginolyticus was both up-regulated and reached the maximum level at 8 and 16 h post-stimulation, respectively, and then dropped back to the original level. Bacteriolytic activity of the lysozyme against different bacterial cultures was determined by the solid phase and turbidimetric assays. The results demonstrated that the lysozyme we obtained was not only against Grampositive and Gram-negative bacteria but also against shrimp pathogens V. alginolyticus and V. parahemolyticus. In addition, the study of the inhibition mechanism revealed that the antibacterial activity of the lysozyme was a result of the bactericidal effect.

关键词： Lysozyme C Litopenaeus stylirostris PCR-cloning Expression Antibacterial activity

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An analysis of the wide area differential method of geostationary orbit satellites

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science china(Physics,Mechanics & Astronomy) 2009年第2期52卷 310-314页

作者： CAI ChengLin1,2,3?, LI XiaoHui1 & WU HaiTao1 1 National Time Service Center, chinese academy of sciences, Lintong 710600, china 2 Hunan Institute of Humanities, science and Technology, Loudi 417000, china 3 graduate university of chinese academy of sciences, beijing 100049, china National Time Service Center Chinese Academy of Sciences Lintong China Hunan Institute of Humanities Science and Technology Loudi China graduate university of chinese academy of sciences Beijing China

This work aims to obtain a wide area differential method for geostationary orbit (GEO) constellation. A comparison between the dilution of precision (DOP) of four-dimensional (4D) calculation including sa- tellite clock errors and ephemeris errors and that of three-dimensional (3D) calculation only including ephemeris errors with the inverse positioning theory of GPS shows the conclusion that all the 3D PDOPs are greatly reduced. Based on this, a basic idea of correcting satellite clock errors and ephem- eris errors apart is put forward, and moreover, a specific method of separation is proposed. Satellite clock errors are separated in a master station with time synchronization, and all the remaining pseu- do-range errors after the satellite clock errors have been deducted are used to work out ephemeris corrections of all GEO satellites. By a comparative analysis of user positioning accuracy before and after differential, the wide area differential method is verified to be quite valid for GEO constellation.

关键词： geostationary orbitsatellite dilution of precision satellite ephemeris errors satellite clock errors wide area differential method

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Paillier's trapdoor function hides Θ(n) bits

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science china(Information sciences) 2011年第9期54卷 1827-1836页

作者： SU Dong & Lü KeWei State Key Laboratory of Information Security,graduate university of chinese academy of sciences,beijing 100049,china State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing China

In this paper,we re-examine the bit security of Paillier’s trapdoor *** show that given a random w=gcyN mod N2 ∈ZN2* the most significant bit of its class c is a hard-core predicate,under a standard assumption that is computing composite residuosity class is *** the simultaneous security,we prove that n number of the class c’s bits are simultaneously hard-core under the standard assumption,where n is the length of c.

关键词： Paillier’s trapdoor function hard-core predicate hard-core function simultaneous security most significant bit

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Suprathermal particle events observed by WIND spacecraft in interplanetary space during 1995―1999 and their classification

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science china(Technological sciences) 2008年第9期51卷 1542-1553页

作者： SUN LingPeng1,2, WU DeJin1 & WANG DeYu1 1 Purple Mountain Observatory, chinese academy of sciences, Nanjing 210008, china 2 graduate School of chinese academy of sciences, beijing 100049, china Purple Mountain Observatory Chinese Academy of Sciences graduate School of chinese academy of sciences

Fifty-five suprathermal particle events were selected from WIND observations between 1995 and 1999. Based on systematic analysis on the observational characteristics of these events a two-parameter (the rising time and the flux ratio of electrons to protons in each event) classification method was proposed to classify these events. The three clas-sified classes are (1) impulsive electron events with the flux ratio of electrons to protons being bigger than 1 and rising time being shorter than 200 min, (2) impulsive proton events with the flux ratio being smaller than 1 and rising time being shorter than 200 min, and (3) gradual proton events with the flux ratio being smaller than 1 and the rising time being longer than 200 min. In the past, "impulsive solar electron events" were under in-tense research. However, because the selection standards of their velocity dispersions or pitch-angle distributions were inadequate, statistical surveys of selected events were dif-ferent from each other and even some conclusions were not consistent with the theory, for example, the relation of type-III solar radio bursts to the "impulsive solar electron events". The first class of impulsive electron events are associated with type-III radio bursts and with clear velocity dispersions; therefore they ought to originate from the Sun. The second class of the events, which have short continuance time and usually are not associated with type-III radio bursts and without velocity dispersion, are still far away from inter-planetary shocks and most of them do not one-to-one correspond to corrotating interact-ing regions (CIRs); such events are possible results of local interplanetary magnetic field reconnection or electromagnetic disturbances. Finally, about 2/3 gradual proton events of the third class occur with interplanetary shocks, the delay times of which are almost equal to the rising time. Some of these events can be understood as particle accelerations by shocks.

关键词： suprathermal particles solar wind plasma solar eruptive activity interplanetary active regions

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A class of binary cyclic codes with five weights

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science china Mathematics 2010年第12期53卷 3279-3286页

作者： LI ChunLei 1 , ZENG XiangYong 1, & HU Lei 2 1 Faculty of Mathematics and Computer science, Hubei university, Wuhan 430062, china 2 The State Key Laboratory of Information Security, graduate School of chinese academy of sciences, beijing 100049, china Faculty of Mathematics and Computer science Hubei University The State Key Laboratory of Information Security Graduate School of Chinese Academy of Sciences

In this paper, the dual code of the binary cyclic code of length 2 n-1 with three zeros α, α t 1 and α t 2 is proven to have five nonzero Hamming weights in the case that n 4 is even and t1 = 2 n/2 + 1, t2 = 2 n-1-2 n/2+1 + 1 or 2 n/2 + 3, where α is a primitive element of the finite field F 2 n . The dual code is a divisible code of level n/2+1, and its weight distribution is also completely determined. When n = 4, the dual code satisfies Ward's bound.

关键词： cyclic code Niho exponent exponential sum Pless power moment identity weight distribution

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Improving the accuracy of image-based forest fire recognition and spatial positioning

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science china(Technological sciences) 2010年第S1期53卷 184-190页

作者： JIANG LiLi 1,QI QingWen 1,ZHANG An 1,GUO ChaoHui 2 & CHENG Xi 1,3 1 Institute of Geographical sciences and Natural Resources Research,chinese academy of sciences,beijing 100101,china 2 china Center for Resources Satellite Data and Applications,beijing 100094,china 3graduate university of chinese academy of sciences,beijing 100049,china Institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences Beijing China china Center for Resources Satellite Data and Applications Beijing China graduate university of chinese academy of sciences Beijing China

Forest fires are frequent natural *** is necessary to explore advanced means to monitor,recognize and locate forest fires so as to establish a scientific system for the early detection,real-time positioning and quick fighting of forest *** paper mainly expounds methods and algorithms for improving accuracy and removing uncertainty in image-based forest fire recognition and spatial ***,we discuss a method of forest fire recognition in visible-light *** are four aspects to improve accuracy and remove uncertainty in fire recognition:(1)eliminating factors of interference such as road and sky with high brightness,red leaves,other colored objects and objects that are lit up at night,(2)excluding imaging for specific periods and azimuth angles for which interference phenomena repeatedly occur,(3)improving the thresholding method for determining the flame border in image processing by adjusting the threshold to the season,weather and region,and (4)integrating the visible-light image method with infrared image ***,we examine infrared-image-based methods and approaches of improving the accuracy of forest fire recognition by combining the spectrum threshold with an object feature value such as the normalized difference vegetation index and excluding factors of disturbance such as interference signals,extreme weather and high-temperature ***,a method of visible analysis to enhance the accuracy of forest fire positioning is examined and realized;the method includes decreasing the visual angle,selecting central points,selecting the largest spots,and judging the selection of fire spots according to the central *** studies are examined and the results are found to be satisfactory.

关键词： forest fire monitoring spatial positioning accuracy improvement

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Forecasting the summer rainfall in North china using the year-to-year increment approach

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science china Earth sciences 2009年第4期52卷 532-539页

作者： FAN Ke1, LIN MeiJing1,2 & GAO YuZhong3 1 Nansen-Zhu International Research Center, Institute of Atmospheric Physics, chinese academy of sciences, beijing 100029, china 2 graduate university of the chinese academy of sciences, beijing 100049, china 3 Heilongjiang Meteorological Administration, Harbin 150030, china Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China graduate university of the chinese academy of sciences Beijing China Heilongjiang Meteorological Administration Harbin China

A new approach to forecasting the year-to-year increment of rainfall in North china in July-August (JA) is proposed. DY is defined as the difference of a variable between the current year and the preceding year (year-to-year increment). NR denotes the seasonal mean precipitation rate over North china in JA. After analyzing the atmospheric circulation anomalies associated with the DY of NR, five key predictors for the DY of NR have been identified. The prediction model for the DY of NR is established by using multi-linear regression method and the NR is obtained (the current forecasted DY of NR added to the preceding observed NR). The prediction model shows a high correlation coefficient (0.8) between the simulated and the observed DY of NR throughout period 1965-1999, with an average relative root mean square error of 19% for the percentage of precipitation rate anomaly over North china. The prediction model makes a hindcast for 2000-2007, with an average relative root mean square error of 21% for the percentage of precipitation rate anomaly over North china. The model reproduces the downward trend of the percentage of precipitation rate anomaly over North china during 1965-2006. Because the current operational prediction models of the summer precipitation have average forecast scores of 60%-70%, it has been more difficult to forecast the summer rainfall over North china. Thus this new approach for predicting the year-to-year increment of the summer precipitation (and hence the summer precipitation itself) has the potential to significantly improve operational forecasting skill for summer precipitation.

关键词： annual increment North china precipitation prediction prediction skill

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A puzzle of the radio-quiet quasar PG 1407+265:Are optical and X-ray emissions produced from a relativistic jet?

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science china(Physics,Mechanics & Astronomy) 2011年第1期54卷 183-186页

作者： CHEN Liang 1,2,3 & BAI JinMing 1,2 1 National Astronomical Observatories/Yunnan Observatory,chinese academy of sciences,Kunming 650011,china 2 Key Laboratory for the Structure and Evolution of Celestial Objects,chinese academy of sciences,Kunming 650011,china 3 graduate university of chinese academy of sciences,beijing 100049,china chinese academy of sciences National Astronomical Observatories/Yunnan Observatory Kunming China (GRID:grid.9227.e) (ISNI:***) chinese academy of sciences Key Laboratory for the Structure and Evolution of Celestial Objects Kunming China (GRID:grid.9227.e) (ISNI:***) graduate university of chinese academy of sciences Beijing China (GRID:grid.458514.9) chinese academy of sciences National Astronomical Observatories/Yunnan Observatory Kunming China (GRID:grid.9227.e) (ISNI:***) chinese academy of sciences Key Laboratory for the Structure and Evolution of Celestial Objects Kunming China (GRID:grid.9227.e) (ISNI:***)

PG 1407+265 is a radio quiet quasar that has a relativistic *** this report,we show some peculiar properties of its optical and X-ray emissions,which indicate possible non-thermal origins produced from the *** use a simple synchrotron + synchrotron self Compton (SSC) model to fit the emissions with different ratios of energy densities between the magnetic field and electrons (η≡U B/U e),which predicts a different γ-ray *** First LAT AGN Catalog (1LAC) did not include PG 1407+265,which indicates an upper limit of γ-ray *** upper limit constrains the ratio to be unreasonably large (η≥10 4-5).This inversely indicates that the optical and X-ray emissions may not be produced from the beaming *** discuss the physical implications of these results.

关键词： active galactic nuclei jet non-thermal emission PG 1407+265

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