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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 2.0093, China 2.Guangzhou Institute of Geochemistry, {2. academy of sciences, Guangzhou 510640, China 3 graduate university of {2. 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 {2. 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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Periodicity of Retzius lines in fossil Pongo from South China

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chinese Science Bulletin 2012年第7期57卷 790-794页

作者： HU Rong1,2.3, ZHAO LingXia1,2.& WU XinZhi2.1 Key Laboratory of Evolutionary Systematics of Vertebrates, Institute of Vertebrate Paleontology and Paleoanthropology, chinese academy of {2., beijing 100044, China 2.Laboratory of Human Evolution, Institute of Vertebrate Paleontology and Paleoanthropology, chinese academy of {2., beijing 100044, China 3 graduate university of chinese academy of {2., beijing 100049, China Laboratory of Human Evolution Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China

Periodicity of Retzius lines is a key factor in dental development. In this study, we examined the periodicity of Retzius lines in fossil Pongo from South China using polarized light microscope observation of dental ground sections. The periodicities all of the 15 teeth were 9 d. Comparisons of periodicity were made with extant primates, fossil apes and hominins. Periodicity of fossil Pongo from South China was relatively long but fell within the variation of extant Pongo, Gorilla and modern human, and longer than periodicity of Pan and other extant primates. Fossil Pongo from South China was similar to Lufengpithecus and Sivapithecus, shorter than Gigantopithecus and longer than European and African fossil apes and most early hominins in periodicity. Generally, the periodicities of Asian large-body fossil apes were longer than the periodicities of European and African large-body fossil apes in Miocene. Difference among species and trend of evolution in periodicity were analyzed and discussed. We found that periodicity might gradually increase from Proconsul in early Miocene to several fossil apes in Miocene and then Gigantopithecus in Pleistocene. In addition, this study made correlate analysis between periodicity and body mass respectively in males and females of six extant apes and five fossil apes, and found that periodicity positively correlated with body mass.

关键词：周期性变化中国南方大猩猩化石灵长类动物早中新世类人猿显微镜观察

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Regional soil moisture simulation for Shaanxi Province using SWAT model validation and trend analysis

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Science China Earth sciences 2010年第4期53卷 575-590页

作者： LI MingXing1,2.MA ZhuGuo1 & DU JiWen3 1 Key Laboratory of Regional Climate-Environment Research for Temperate East Asia,Institute of Atmospheric Physics,chinese academy of {2.,beijing 10002.,China 2.graduate university of chinese academy of {2.,beijing 100049,China 3 Shaanxi Administration of Meteorology,Xi’an 710014,China Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China graduate university of {2. academy of sciences Beijing China Shaanxi Administration of Meteorology Xi’an China

The soil moisture in Shaanxi Province,a region with complex topography,is simulated using the distributed hydrological model Soil Water Assessment Tool(SWAT).Comparison and contrast of modeled and observed soil moisture show that the SWAT model can reasonably simulate the long-term trend in soil moisture and the spatiotemporal variability of soil moisture in the *** to NCEP/NCAR and ERA40 reanalysis of soil moisture show that the trend of variability in soil moisture simulated by SWAT is more consistent with the *** model results suggested that high soil moisture in surface soil layers appears in the southern Shaanxi with high vegetation cover,and the Qinling mountainous region with frequent orographic *** deeper soil layers,high soil moisture appears in the river basins and *** regional soil moisture showed a generally decreasing trend on all soil layers from 1951 to 2.04,with a stronger and significant decreasing trend in deeper soil layers,especially in the northern parts of the province.

关键词： SWAT soil moisture content simulation validation trend analysis

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Analysis of a kind of quantum cryptographic schemes based on secret sharing

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Science China(Physics,Mechanics & Astronomy) 2009年第9期52卷 1313-1316页

作者： ZHANG XingLan1 & JI DongYao2.1 College of Computer Science and Technology, beijing university of Technology, beijing 10012., China 2.State Key Laboratory of Information Security, graduate university of chinese academy of sciences, beijing 100049, China College of Computer Science and Technology Beijing University of Technology Beijing China State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing China

Recently, Yang et al. proposed a kind of quantum cryptographic schemes based on secret sharing. The main idea is drawn from the case, where any n participants who share a secret K can co-operate as K does. This process can be applied to encryption, authentication, signature and so on. Unfortunately, since there is no identity authentication of the share's holder, these schemes inherit the limitation of secret sharing in practice. If some participants do not follow the protocol, the protocol would be a failure at last. Moreover, these schemes encounter another serious attack. Any two participants can co-operate to defeat the schemes by sending different shares to the parties unknown to the distributor of the secret K, such that these parties can execute the protocol as well. The attack proves that it is not enough for quantum cryptographic schemes that only the secret key is secure.

关键词： quantum identity authentication quantum secure direct communication quantum signature secret sharing

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Elemental and isotopic compositions of the hydrothermal sulfide on the East Pacific Rise near 13°N

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Science China Earth sciences 2010年第2期53卷 253-266页

作者： ZENG ZhiGang1,CHEN DaiGeng1,2.YIN XueBo1,WANG XiaoYuan1,ZHANG GuoLiang1,2.& WANG XiaoMei1,2.1 Seafloor Hydrothermal Activity Laboratory of the Key Laboratory of Marine Geology and Environment,Institute of Oceanology,chinese academy of {2.,Qingdao 2.6071,China 2.graduate School of chinese academy of {2.,beijing 100049,China Seafloor Hydrothermal Activity Laboratory of the Key Laboratory of Marine Geology and Environment Institute of Oceanology Chinese Academy of Sciences Qingdao China graduate School of chinese {2. of sciences Beijing China

The mineralogical,elemental,and isotopic characteristics of a hydrothermal sulfide sample from one dredge station (12.42.30’N,103°54.48’W,water depth 2.55 m) on the East Pacific Rise near 13°N were *** hydrothermal sulfide was composed mainly of sphalerite,chalcopyrite,and pyrite and was a Zn-rich sulfide;in layer ep-s-1,goethite formed by secondary oxidation was *** concentrations of rare elements,such as Li (0.15×10-6-0.30×10-6),Be (0.01×10-6-0.05×10-6),Zr (73.8×10-9-1344×10-9),Nb (8.14×10-9-64.7×10-9),Hf (2.54×10-9-2..0×10-9),and Ta (0.2.3×10-9-1.2.×10-9),were far lower in the hydrothermal sulfide than in the ocean crust,whereas the content of Au was higher and the contents of Co,Ni,Sr,Cs,Ba,Bi,and U were *** correlations between Zn and Cr,Cd and Ga,Cu and P,P and In (R2.> 0.8) were positive,whereas those between Zn and Fe,Cu,and Ba (R2.> 0.8) were distinctly *** low-temperature mineral assemblages to high-temperature mineral assemblages,the spatial distributions of dispersive and rare elements (***,Li,Cs) in the hydrothermal sulfide displayed corresponding *** variations observed in some elements (e.g.,Cd,Cs,P) are controlled by Zn,Fe,and Cu sulfides,*** weathering accounts for the enrichment of V,Mn,and rare earth elements (REE) in the henna sulfide-oxidation layer that bears the secondary oxide mineral,leading to identical REE patterns for this layer (ep-s-1) and *** weathering also distinctly affects the correlations between the element ratios of the hydrothermal *** high-temperature mineral assemblages to low-temperature mineral assemblages,Fe content and δ 34S value of the hydrothermal sulfide increase gradually,and Zn content and lead isotopic ratios decrease gradually on the contrary,which indicate the influences of seawater on elements and the sulfur and lead isotopic compositions enhance gradually during the formation of hydrothermal sulfides.

关键词： variation element isotopic composition hydrothermal sulfide East Pacific Rise 13oN

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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 {2., Nanjing 2.0008, China 2.graduate School of chinese academy of {2., beijing 100049, China Purple Mountain Observatory Chinese Academy of Sciences graduate School of chinese {2. 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 2.0 min, (2. impulsive proton events with the flux ratio being smaller than 1 and rising time being shorter than 2.0 min, and (3) gradual proton events with the flux ratio being smaller than 1 and the rising time being longer than 2.0 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 new class of symmetric periodic solutions of the spatial elliptic restricted three-body problem

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Science China(Physics,Mechanics & Astronomy) 2009年第9期52卷 1404-1413页

作者： XU XingBo1,2.& FU YanNing1 1 Purple Mountain Observatory, chinese academy of {2., Nanjing 2.0008, China 2.graduate university of chinese academy of {2., beijing 100039, China Purple Mountain Observatory Chinese Academy of Sciences Nanjing China graduate university of {2. academy of sciences Beijing China

We show that there exists a new class of symmetric periodic solutions of the spatial elliptic restricted three-body problem. In such a solution, the infinitesimal body is confined to the vicinity of a primary and moves on a nearly circular orbit. This orbit is almost perpendicular to the orbital plane of the primaries, where the line of symmetry of the orbit lies. The existence is shown by applying a corollary of Arenstorf's fixed point theorem to a periodicity equation system of the problem. And this existence doesn't require any restriction on the mass ratio of the primaries, nor on the eccentricity of their relative elliptic orbit. Potential relevance of this new class of periodic solutions to real celestial body systems and the follow-up studies in this respect are also discussed.

关键词： periodic orbits spatial restricted three-body problem symmetric orbits averaging

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A puzzle of the radio-quiet quasar PG 1407+2.5: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 {2.,Kunming 650011,China 2.Key Laboratory for the Structure and Evolution of Celestial Objects,chinese academy of {2.,Kunming 650011,China 3 graduate university of chinese academy of {2.,beijing {12.,China chinese academy of {2. National Astronomical Observatories/Yunnan Observatory Kunming China (GRID:grid.9227.e) (ISNI:***) chinese academy of {2. Key Laboratory for the Structure and Evolution of Celestial Objects Kunming China (GRID:grid.9227.e) (ISNI:***) graduate university of {2. academy of sciences Beijing China (GRID:grid.458514.9) chinese academy of {2. National Astronomical Observatories/Yunnan Observatory Kunming China (GRID:grid.9227.e) (ISNI:***) chinese academy of {2. Key Laboratory for the Structure and Evolution of Celestial Objects Kunming China (GRID:grid.9227.e) (ISNI:***)

PG 1407+2.5 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+2.5,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+2.5

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Monitoring Dynamic Change of Land Cover Based on SVM and Satellite Images in Hanoi,Vietnam

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Wuhan university Journal of Natural sciences 2010年第4期15卷 355-362页

作者： ZHAO Jinling1,2. LIU Chuang1, 3 1. Institute of Geographic sciences and Natural Resources Research, chinese {2. of sciences, beijing 100101, China 2. graduate university of chinese academy of sciences, beijing 100049, China 3. College of Resources Science and Technology, beijing Normal university, beijing 100875, China Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China graduate university of {2. academy of sciences Beijing China College of Resources Science and Technology Beijing Normal University Beijing China

An integral method,combining support vector ma-chine (SVM) with remote-sensing analysis techniques,was ex-plored to monitor Hanoi’s dynamic change of land cover. The landsat thematic mapper (TM) image in 1993,the enhanced the-matic mapper plus (ETM+) image in 2.00,and the image with the charge-coupled device camera (CCD) on the China-Brazil earth resources satellite (CBERS) in 2.08 were used. Six land-cover types,including built-up areas,woodland,cropland,sand,water body and unused land,were identified. The detected results showed visually the rapid urban expansion as well as land-cover change of Hanoi from 1993 to 2.08. There were 12.637.54 hm2.cropland de-creased between 1993 and 2.00,and 8 2.7.6 hm2.cropland de-creased between 2.00 and 2.08. Compared with cropland,wood-land firstly decreased and then increased,and the other types did not change significantly. The results indicate that CBERS dataset has the application potential in world resources researches.

关键词： land cover the China-Brazil earth resources satellite (CBERS) support vector machine (SVM) change detection

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Research on applying physical chaos generator to spacecraft information security

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Science China(Technological sciences) 2009年第5期52卷 1463-1470页

作者： ZHAO HePing State Key Laboratory of Information Security,graduate university of {2. academy of sciences,beijing 100049,China China academy of Space Technology,beijing 100094,China State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences China academy of Space Technology

The effectiveness of a short-length message extension method based on physical chaos generator was analyzed and the entropy of the extended message was calculated in this *** analysis demon-strated that with the mentioned method the entropy of short-length messages,which are repeatedly used in spacecraft data systems,is obviously increased,and the security of transmission is enhanced as *** paper also presented an improvement of the protocol for secret key agreement presented by *** and *** of depending on characteristics of communication channel,this method takes advantage of the random data produced by physical chaos generator to preset the initial parameters of the procedure on both sides of communication,so that the procedure and quantity of cipher key can be precisely *** method can be used to cipher key management of se-cure communication between long life-span spacecraft and ground system.

关键词： physical chaos generator spacecraft information security message extension cipher key management

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