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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 sciences,Qingdao 266071,china 2.graduate School of chinese academy of sciences,Beijing 100049,china 1. Seafloor Hydrothermal Activity Laboratory of the Key Laboratory of Marine Geology and Environment Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China2. Graduate School of Chinese Academy of Sciences Beijing 100049 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 2655 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 (73.8×10-9-13.4×10-9),Nb (8.14×10-9-64.7×10-9),Hf (2.54×10-9-28.0×10-9),and Ta (0.203×10-9-1.21×10-9),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 13.N

CBCR:CBC MAC with rotating transformations

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Science china(Information sciences) 2011年第11期54卷 2247-2255页

作者： ZHANG LiTing 1,2,WU WenLing 1,ZHANG Lei 1 & WANG Peng 21 State Key Laboratory of Information Security,Institute of Software,chinese academy of sciences,Beijing 100190,china 2.graduate university of chinese academy of sciences,Beijing 100049,china 1. State Key Laboratory of Information Security Institute of Software Chinese Academy of Sciences Beijing 100190 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Message authentication codes (MACs) are widely used to protect data integrity and data origin authentication in *** this paper,we propose a new block-cipher-based MAC algorithm,CBCR,with provable security for arbitrary-length *** adopts rotating operations in the end of cipherblock-chaining structure,and it appends fixed-length prefixes to all messages,which implies flexible usages in *** example,these fixed-length prefixes can be filled with some security parameters,message redundancies,*** also propose CBCR0,a special case of CBCR that sets its prefix to be an all-zero *** with CMAC,a recommended standard by the US National Institute of Standards and Technology (NIST),CBCR0 enjoys all the advantages that CMAC has,but requires less memory;so,in practical applications,CBCR0 behaves as well as CMAC does,and it is even more suitable for environments with limited memory resources,*** cards.

关键词： message authentication code cipher block chaining block cipher provable security

Effects of combined substitution of Dy and Mo or Si on the crystal structures and magnetic properties of Nd_(1-y)Dy_yFe_(11-x)TiM_x(M=Mo,Si) compounds

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Science china Chemistry 2009年第8期52卷 1097-1103页

作者： LI XiangJun,ZHENG Na,HU ZhongBo & YUAN ZhuoBin College of Chemistry and Chemical Engineering,graduate university of chinese academy of sciences,Beijing 100049,china 1. College of Chemistry and Chemical Engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China

A series of Nd1-yDyyFe11-xTiMx(M=Mo,Si) alloys have been prepared by arc melting and studied by X-ray diffraction and neutron *** samples are found to crystallize in the ThMn12-type *** lattice parameters a and c and unit cell volume V of Nd0.5Dy0.5Fe11-xTiMox alloys increase linearly with increasing content of Mo(x),while the lattice parameters a and c and unit cell volume V of Nd0.5Dy0.5Fe11-xTiSix alloys decrease linearly with increasing content of Si(x).In NdyDy1-yFe11-xTiMx(M=Mo,Si) compounds,Ti and Mo atoms preferentially occupy the 8i sites and Si atoms preferentially occupy the 8j and 8f *** measurements show that the substitution of Fe by either Mo or Si leads to a decrease in the Curie temperature.

关键词： rare earth-transition metal compounds crystal structure X-ray diffraction neutron diffraction

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 sciences, Beijing 100044, china 2 Laboratory of Human Evolution, Institute of Vertebrate Paleontology and Paleoanthropology, chinese academy of sciences, Beijing 100044, china 3 graduate university of chinese academy of sciences, Beijing {13., 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

Improvement of a 3D radar backscattering model using matrix-doubling method

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Science china Earth sciences 2010年第7期53卷 1029-1035页

作者： NI WenJian1,2, GUO ZhiFeng1 & SUN GuoQing3 1 State Key Laboratory of Remote Sensing Science, jointly sponsored by the Institute of Remote Sensing Applications of chinese academy of sciences and Beijing Normal university, Beijing 100101, china 2.graduate university of chinese academy of sciences, Beijing 100049, china 3 Department of Geography, university of Maryland, College Park, MD 27042, USA 1. State Key Laboratory of Remote Sensing Science jointly sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Department of Geography University of Maryland College Park MD 27042 USA

Radiative transfer models have been widely used to simulate the radar backscattering from forested areas. A three-dimensional radar backscatter model of forest canopy developed in previous studies takes full account of spatial position of trees in a forest stand, and the interactions among crown, trunk and ground surface. The model predicted well for the co-polarized backscatter measurements, but underestimated the backscattering for cross-polarization, primarily because only the first-order scattering within tree crowns was considered in the model. The backscattering at cross-polarization depends strongly on multiple scatter- ing within tree crowns. To produce good estimations for cross-polarized component, the matrix-doubling method is employed here to compute multiple-scattering within the crown. The modified model is compared with the original model, and the field forest measurements and AIRSAR data are used for validation of the modified model. The cross-polarization backscattering is improved in different degrees for different crown structures and at different bands.

关键词： remote sensing forestry electromagnetic propagation radar backscattering model matrix-doubling

Construction of AFLP-based genetic linkage maps for the chinese shrimp Fenneropaeneus chinensis

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chinese Science Bulletin 2008年第8期53卷 1205-1216页

作者： TIAN Yi1,2,3,4, KONG Jie1↑ & WANG WeiJi1 1 Yellow Sea Fisheries Research Institute, chinese academy of Fishery Science, Qingdao 266071, china 2 College of Life Science and Technology, Dalian Fisheries university, Dalian 116023, china 3 Institute of Oceanology, chinese academy of sciences, Qingdao 266071, china 4 graduate university of chinese academy of sciences, Beijing 100049, china chinese Acad Fisheries Sci Yellow Sea Fisheries Res Inst Qingdao 266071 Peoples R China.

Fenneropaeneus chinensis is an important species in marine fishery resources and aquaculture in china. A genetic linkage map is essential for improving the efficiency of its breeding by marker-as- sisted selection and identifying commercially important genes. Linkage maps of F. chinensis were constructed with an F2 mapping population (110 progenies) using amplified fragment length polymor- phic (AFLP) marker in this study. Fifty-five AFLP primer combinations produced 532 AFLP markers fitting for map strategy in mapping family. The markers with 3:1 segregating ratios were analyzed using F2 intercross model for the common linkage map, while the markers with 1:1 ratio were analyzed using the pseudo-testcross strategy. The maps of male, female and common were constructed. The female map included 103 markers that formed 28 linkage groups, covering a total length of 1090 cM. All mark- ers were linked with the linkage groups. Segregation distortion was observed for 6 of 103 markers in the female map. The average distance between markers was 14.53 cM and ranged from 4.4 to 24.8 cM. The male map included 144 markers that formed 35 linkage groups. Ten markers remained unlinked in male map. Segregation distortion was observed for 7 of 144 markers in the male map. The total dis- tance of male map covered 1617 cM. The average distance between markers was 16.36 cM. The male map was 32.6% longer than the female map, which may reflect sex-specific recombination rates in chinese shrimp. The common map was composed of 216 markers, including in 44 linkage groups covering a total distance of 1772.1 cM. Two markers remained unlinked. No distorted markers of 216 markers were shown in the common map. The distance between markers was 10.42 cM. An average estimated genome size for the chinese shrimp was 2420 cM, which was consistent with the relative size of the Penaeid genome. The distribution of AFLP markers was relatively even in chromosomes of Chi- nese shrimp maps. The linkage analysis

关键词： AFLP 海洋渔业虾中国

Existence of unbiased estimate of regression parameters in simple linear EV models

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Science china Mathematics 2005年第7期48卷 915-928页

作者： LIU Jixue & CHEN Xiru Department of Statistics and Finance, university of Science and Technology of china, Hefei 230026, china Department of Mathematics, graduate School of chinese academy of sciences, Beijing 100049, china Department of Statistics and Finance University of Science and Technology of China Hefei 230026 China Department of Mathematics Graduate School Chinese Academy of Sciences Beijing 100049 China

It is well known that for one-dimensional normal EV regression model X = x+ u,Y =α+βx+e, where x, u, e are mutually independent normal variables and Eu=Ee=0, the regression parameters a and β are not identifiable without some restriction imposed on the parameters. This paper discusses the problem of existence of unbiased estimate for a and β under some restrictions commonly used in practice. It is proved that the unbiased estimate does not exist under many such restrictions. We also point out one important case in which the unbiased estimates of a and β exist, and the form of the MVUE of a and β are also given.

关键词： EV regression model unbiased estimate identiflability.

Application of three-dimensional discrete element face-to-face contact model with fissure water pressure to stability analysis of landslide in Panluo iron mine

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Science china(Technological sciences) 2005年第z1期48卷 146-156页

作者： ZHANG Lei1,2, WEI Zuoan1, LIU Xiaoyu1 & LI Shihai1 1.Institute of Mechanics, chinese academy of sciences, Beijing 100080, china 2.graduate School, chinese academy of sciences, Beijing 100060, china chinese Acad Sci Inst Mech Beijing 100080 Peoples R China chinese Acad Sci Grad Sch Beijing 100060 Peoples R China

Three-dimensional discrete element face-to-face contact model with fissure water pressure is established in this paper and the model is used to simulate three-stage process of landslide under fissure water pressure in the opencast mine, according to the actual state of landslide in Panluo iron mine where landslide happened in 1990 and was fathered in 1999. The calculation results show that fissure water pressure on the sliding surface is the main reason causing landslide and the local soft interlayer weakens the stability of slope. If the discrete element method adopts the same assumption as the limit equilibrium method, the results of two methods are in good agreement; while if the assumption is not adopted in the discrete element method, the critical φ numerically calculated is less than the one calculated by use of the limit equilibrium method for the sameC. Thus, from an engineering point of view, the result from the discrete element model simulation is safer and has more widely application since the discrete element model takes into account the effect of rock mass structures.

关键词： face-to-facecontactmodel, fissure water pressure, three-dimensional discrete element method,landslide.

New research progress on the ultrastructure of tectonically deformed coals

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Progress in Natural Science:Materials International 2009年第11期19卷 1455-1466页

作者： Yiwen Ju,Xiaoshi Li Laboratory of Computational Geodynamics,College of Earth Science,graduate university of chinese academy of sciences,Beijing 100049,china [a]Laboratory of Computational Geodynamics College of Earth Science Graduate University of Chinese Academy of Sciences Beijing 100049 China

The structure of tectonically deformed coals shows some characteristics and regulations on the ultra-scale when influenced by different factors such as temperature,pressure and directional *** of the macromolecular structure may induce changes in the nano-scale pore structure,which are very important for gas adsorption and *** geological impact of different mechanisms of deformation on different types of ultrastructure of tectonically deformed coals is not only of significance as a topic for scientific research, but also in studying environments of metamorphism-deformation at differing metamorphic *** research is also very important in studying the accumulation and occurrence conditions of coalbed methane gas,mechanisms of coal and gas outbursts,predictions of coalbed methane resources and dangers of coal and gas *** paper analyzes current research,within china and other countries, in the ultrastructure of tectonically deformed *** research includes(1) structural models of tectonically deformed coals;(2) the relationship between ultrastructure and stress;(3) the structure of tectonically deformed coals and its strain *** results are also based on our own experiments including vitirnite reflectance(Ro,max),X-ray diffraction(XRD) and nuclear magnetic resonance (NMR(CP/MAS + TOSS)).We discuss the important effects of the structure of tectonically deformed coals and their physical properties,and then point out some problems concerning the research progress of tectonically deformed coals.

关键词： Tectonically deformed coals Ultrastructure Pore structure Tectonic stress Strain environment