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ANALYSIS OF 3-D FOUNDATION WAVE PROBLEMS BY MAPPED DYNAMIC INFINITE elements

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Science China Mathematics 1989年第4期32卷 479-491页

作者：赵崇斌张楚汉张光斗 Tsinghua University Beijing

From wave equations of 3-D visco-elasticity and Garlerkin weighted residual approxima-tion, discretized formulations for 3-D visco-elastic foundations Lave been derived. In addition,a 3-D mapped dynamic infinite element (IFEM) and its basic principle and constituting pro-cedure are presented. This IFEM can easily be coupled with the normal FEM, and it retainsthe advantages of being suitable for simulation of complicated media and boundary conditions,and of reducing the degrees of freedom by a large number. The example given in this paperverifies the excellent accuracy of IFEM. Finally, study has been made to evaluate the effectsof plate flexibility on dynamic compliances of a 3-D foundation on elastic half space. Re-sults show that only if the elastic modulus ratio of the plate and foundation E_F/E_R≥10~4 - 10~5,can the plate be treated as a rigid base.

关键词： foundations wave propagation infinite elements.

CONTENT　AND　DISTRIBUTION　OF　TRACE　elements.IN　SOILS　OF　THE　DAM　RIVER　AND　TUOTUO　RIVER　BASINS

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Chinese Geographical Science 1995年第2期5卷 157-169页

作者：邵庆春邓伟孙广友 Changchun Institute of Geography the Chinese Academy of Sciences Changchun PRC

Natural contents and distribution of trace elements.in soils of the Dam River and Tuotuo River basins are demonstrated in this paper. By using contrasting methods. it is found that the content of trace elements.of soil in the region is at the lower limit of the world's soil content level, that the tendency of the average trace element content in the four main types of soil is shown as: alpine mountain meadow soil>marsh soil>alpine mountain steppe soil> alpine mountain cryogenic soil. the average content of trace elements.such as Cr. Co, Zn, Cu, Hg, Pb, Mo, Mn and Ni in the Dam River basin is higher than that of the Tuotuo River basin except that of the elements.Ba and Sr. In addition. through correlation analysis. the relationship of intergrowth and association among soil elements.are revealed.

关键词： content of trace elements. distribution of trace elements trace element of soils Dam River basin. Tuotuo River basin

REE geochemistry of surface sediments in the Chukchi Sea

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Science China Earth Sciences 2003年第6期46卷 603-611页

作者：陈志华高爱国刘焱光孙海清石学法杨作升 KeyLaboratoryofMarineSedimentologyandEnvironmentalGeology StateOceanicAdministration FirstInstituteofOceanography StateOceanicAdministrationQingdao266061China OceanUniversityofQingdao Qingdao266003China FirstInstituteofOceanography StateOceanicAdministration OceanUniversityofQingdao

Analyses of rare earth elements.(REEs) in 26 surface sediment samples obtained from the Chukchi Sea were conducted using ICP-MS. In general, REEs are relatively rich in fine-grained sediments and deplete in coarse-grained sediments in the Chukchi Sea although REEs have large concentration spans in different types of sediments. Except that a few samples have weak en-richments of light or heavy REEs?most samples exhibit flat shale-normalized REE pattern, indi-cating that surface sediments in the Chukchi Sea are composed dominantly of terrigenous com-ponents experiencing weak chemical weathering. In terms of REE concentrations and other char-acteristic parameters, we inferred that sediments on the eastern and western sides of the Chukchi Sea are derived from landmasses of Alaska and Siberia, respectively; the midsouth sediments are possibly related to northward dispersion of the Yukon River materials. The Herald Shoal in the center of the study area is covered with relict sediment, which has large ratios of light-to-heavy REEs (ΣCe/ΣY ratio) and lacks evident negative Ce anomaly; cerium enrichment is possibly re-lated to manganese transfer under oxidizing conditions in early diagenesis.

关键词： Chukchi Sea, surface sediments, rare earth elements.

Trace element characteristics in the diopsides of peridotite xenoliths: a laser ablation-inductively coupled plasma-mass spectrometry study

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Chinese Science Bulletin 1998年第7期43卷 579-583页

作者： Shaohai Chen Xinghua Zhou S. Y. O’Reilly W. L. Griffin Guohui Zhang M. Zhang Chinese Acad Sci Inst Geol Lab Lithosphere Tecton Evolut Beijing 100029 Peoples R China Macquarie Univ Sch Earth Sci GEMOC Sydney NSW 2109 Australia

Among the various xenoliths entrained by the Cenozoic Hannuoba basalts, peridotite is the most abundant one. The trace elements.of the diopsides from the peridotite xenoliths were analysed by LA-ICP-MS. The overall depletion and some heterogeneity of the continental mantle beneath northern North China Craton were indicated by the characteristics of the trace elements. The ∑REE amount in diopside correlates with the Cr/(Cr+Al) ratio of diopside which is indicative of xenolith’s partial melting degree. As the peridotite hosts and pyroxenite veins show similar REE distribution patterns, the composite xenoliths are probably formed by mantle deformation, rather than by the late metasomatism of mantle fluids/melts.

关键词： LA-ICP-MS diopside trace elements.

Major and trace element studies on garnets from Palaeozoic kimberlite-borne mantle xenoliths and megacrysts from the North China craton

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Science China Earth Sciences 2000年第4期43卷 423-430页

作者：张宏福 M.A.Menzies 路凤香周新华 Laboratory of Lithosphere Tectonic Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Department of Geology Royal Holloway University of London Egham Surrey TW20 OEX UK China University of Geosciences Wuhan 430074 China

Palaeozoic kimberlites from Mengyin, Shandong and Fuxian, Liaoning, eastern China, contain plenty of mantle xenoliths (peridotites, eclogites) and megacrystic minerals. In-situ electron and ion microprobe analyses on garnets from these xenoliths and megacrysts as well as relevant theoretical modeling reveal that these garnets were more or less affected by kimberlitic silicate melts prior to the encapsulation, in which eclogitic garnet from Fuxian, Liaoning Province, was little affected by mantle metasomatism, representing the primitive depleted mantle composition. In contrast, garnet from Mengyin, Shandong Province, and all megacrystic garnets were completely modified by metasomatic melts/fluids and reached perfectly chemical equilibrium, thus reflecting the characteristics of the enriched mantle. It is inferred that old lithospheric mantle beneath the North China craton was fairly strongly modified by metasomatism before Palaeozoic kimberlite emplacement.

关键词： kimberlite garnet ion microprobe trace elements.

Establishment and application of both FLP and Cre site-specific recombination systems at the same position in the genome

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Chinese Science Bulletin 2000年第5期45卷 456-460页

作者： Jilong Chen Jie Liu Yulian Zhang Zhiwei Chen Zhenhua Jin Chinese Acad Sci Inst Dev Biol Beijing 100080 Peoples R China

Both FRT-FRT and LoxP-LoxP sites that are the target sepuences of site-specific recombinases have been constructed in a vector, called C4LFY, using the recombinant DNA technigue. C4LFY also contains P elements. 2 exons and 1 intron of Drosophila yellow gene, yellow promoter and enhancers, and flanking DNA. Since C4LFY made use of two pairs of FRT and LoxP sites, this vector included two site-specific recombination systems. C4LFY was then integrated into Drosophila genome by P-element-mediated germ line transformation. in the presence of the FLP or Cre recombinase, either FLP/FRT or Cre/LoxP recombination reaction was successfully created at the same position in the genome. Using this system, the molecular basis of yellow gene expression and regulation during development have been investigated. Results indicate that the tissue-specific expression of yellow gene is directly regulated by transcriptional enhancers. in addition, the 5’ and 3’ genomic sequences flanking the yellow gene have been

关键词： site-specific recombination transgene gene expression and regulation cis-acting elements.

SUPERCONVERGENCE FOR L^2-PROJECTION IN FINITE elements

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Numerical Mathematics A Journal of Chinese Universities(English Series) 1998年第1期7卷 86-96页

作者：陈传淼

Consider L2-projection uh of u to n-degree finite element space on one-dimensional uniform grids. Two different classes of the orthogonal expansion in an element for constructing a superclose to function uh are proposed and then superconvergence for both uh and Duh are proved. When n is odd and no boundary conditions are prescribed, then uh is of superconvergence at n+1 order Gauss points Gn+1 in each element. When n is even and function values on the boundary are prescribed, then uh is of superconvergence at n+1 order points Zn+1 in each element. If the other boundary conditions are given, then the conclusions are valid in all elements.that its distance from the boundary≥ch|lnh|. The above conclusions are also valid. for n-dergree rectangular element Q1 （n）.

关键词： Superconvegence L^2-projection finite elements.

Synchrotron Radiation Study of the Relic Bones of Bao Zheng

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Chinese Science Bulletin 1993年第10期38卷 812-815页

作者：李士李学军吴兴汉盛发和李国栋 Institute of High Energy Physics Academia Sinica Beijing 100080 PRC Museum of Anhui Province Hefei 230061 PRC Institute of Cultural Relics and Archaeology of Anhui Province Hefei 230061 PRC Institute of Physics Academia Sinica Beijing 100080 PRC

Bao Zheng, styled Xi-ren, a native of Luzhou County (Now Hefei, Anhui Province), was born in the second year of Xiangping (the title of Emperor Zhenzong’s reign, A. D. 999 North Song Dynasty) and died in the 7th year of Jiayou (the title of Emperor Renzong’s reign, A. D. 1062) at the age of 64. In his childhood and youth he was diligent in pursuing his studies. When he was 29 years old, he became a successful candidate in the highest emperial examination and hereafter took official career for more than

关键词： synchrotron radiation (SR)fluorescent analysis Bao Zheng’s relic bones archaeology trace elements.

On visual art elements.of the web interface

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International Journal of Technology Management 2014年第1期 117-119页

作者： Jian Yang School of Arts Sichuan University of Science & Engineering Zigong Sichuan 643000 China

With the rapid development of modern high-tech, human society is advancing towards the information age. The advent of Intemet technology has brought mankind a new communication experience, and it makes communication between people undergo a fimdamental change. Today＇ s information and communication has broken the traditional way, storage, use and exchange of information are all inseparable from the network, the platform. Network development is affecting all aspects of human behavior and production life. In network technology, web interface design is a very important part. Web interface design is inseparable from the visual arts, both in mutual integration and the overall design, so that the web interface has the aesthetic appeal of the visual arts and the humanities connotation. Due to the development of network technology, people also put forward higher requirements for web design. Web interface design should not only reflect the excellent content, but also create one of the most intuitive visual arts presentation form. This text will begin from a Web page design and production, analyzed and studied its visual art elements.to achieve a reasonable and beautiful web interface.

关键词： Web interface visual arts elements.