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A Potential Candidate For the Middle-Upper Cambrian Boundary Stratotype——An Introduction to the Paibi Section in Huayuan,Hunan

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Acta Geologica Sinica(English Edition) 1990年第3期64卷 309-327,344-346+348页

作者： Dong Xiping Department of Geology, Peking university, Beijing Department of Geology Peking University Beijing

The Middle-Upper Cambrian boundary is one of the current stratigraphical problems which remain openin the geological world, since there have been no universally acknowledged delimiting standard and *** on the instruction of Profs. Lu Yanhao and An Taixiang the author studied in details the Paibi Section,which is well exposed as a continuous sequence at an easily accessible locality. The Middle-Upper Cambrianboundary strata are composed of biocalcimicrosparite, indicating the sedimentary environment of anunderwater upheaval on the gentle slope along the frontal margin of the Yangtze carbonate platform. For the upper Middle and lower Upper Cambrian agnostid trilobite zones and conodont zones are erected,and a more accurate correlation between the trilobite and conodont sequences is established. Based on these,the Middle-Upper Cambrian boundary is drawn more reasonably and precisely than what was done before. Inshort, the section studied is superior to other known sections of Middle-Upper Cambrian. and it will probablybe an ideal candidate for the Middle-Upper Cambrian boundary stratotype.

关键词： In An Introduction to the Paibi Section in Huayuan,Hunan A Potential Candidate For the Middle-Upper Cambrian Boundary Stratotype

Palaeogene Biostratigraphic Characteristics of Red Basins In Western Henan and Its Adjacent Areas, With an Outline of Palaeogene Palaeobiogeographic Provinces of China

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Acta Geologica Sinica(English Edition) 1992年第1期66卷 101-117页

作者： Du Hengjian Ma Ancheng Cheng Jie Wu Weimin China university of Geosciences, Beijing Beijing Normal university China university of Geosciences, Beijing Institute of Crustal Dynamics, State Seismological Bureau, Beijing China university of Geosciences Beijing China

This article is a preliminary summary of Paleogene biostratigraphy of the Liguanqiao, Tantou andYuanqu basins, with a new proposal for Paleogene paleobiogeographic provinces of China. On the basis of asynthetic analysis of the geological data, characters of the mammalian assemblages and their comparisons withother corresponding faunas, a new scheme on Paleogene biostratigraphic subdivision of the basins has been putforward here. Based on differences of biostratigraphic sequences, characteristics of mammalian assemblagesand directions of faults controlling Paleogene basins in China, six Paleogene paleobiogeographic provinces ofChina have been proposed in this paper, that is: Tianshan-Yinshan-Tumen Province; Tarim-North China Prov-ince; Kunlun-Qinling Province, Yangtze Province, Nanling and Southeastern Coastal Province, Qinghai andTibet Province.

关键词： With an Outline of Palaeogene Palaeobiogeographic Provinces of China

The Middle Devonian Bimodal Association of Volcanic Rocks in the Northern Area of East Junggar, Xinjiang

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Acta Geologica Sinica(English Edition) 1992年第2期66卷 141-153页

作者： Han Baofu Department of Geology, Peking university, Beijing Department of Geology Peking University Beijing

The Middle Devonian volcanic rocks in the northern area of East Junggar, located between the Ertix andUlungur rivers of northern Xinjiang, may be divided into basic and acid ones. It is evident that a compositionalgap exists between the two groups so that the volcanic rocks are not in line with a calc-alkaline series becausethe intermediate rocks are absent in the area. The fact shows that the volcanic rocks are a typical bimodal asso-ciation. The formation of the bimodal association of volcanic rocks in the area was closely related to continen-tal rifting or continental extension in the Middle Devonian. In such a tectonic setting, magmas were first pro-duced by partial melting of the mantle. Where crustal thinning was greater, the magmas ascended and eruptedon the surface directly so that the basic volcanic rocks formed, but olivine and/or partial pyroxenefractionation occurred in the magmas during their ascent through the thinning crust. On the other hand, wherecrustal thinning was less, ascending mantle-derived magmas reached the lower crust and accumulated there, re-sulting in partial melting of the lower crust and thus giving rise to the contaminated magma which was consoli-dated as acid volcanic rocks on the surface.

关键词： rock REE area The Middle Devonian Bimodal Association of Volcanic Rocks in the Northern Area of East Junggar Xinjiang

FATIGUE FRACTURE BEHAVIOR OF LOW CARBON MARTENSITE AND MARTENSITE/BAINITE DUPLEX STRUCTURE IN STEEL 20CrMnMo

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Acta Metallurgica Sinica(English Letters) 1992年第3期5卷 212-217页

作者： LI Yongjun Xi′an Jiaotong university,Xi′an,China Xi'an Jiaotong Univ Xi'an China

Fatigue crack propagation rate,da/dN,and threshold stress intensity range,ΔK_(th),of steel 20CrMnMo containing low carbon martensite or low carbon martensite/bainite(LCM/B) duplex structure,obtained by oil quenching and austempered at 360℃,have been measured using specimens under four-point *** was also made of the crack path and fracture morphology with relation to *** formation of LCM/B duplex structure,which caused by 20% lower bainite after short-time isothermal treatment,may re- markably increase ΔK_(th)and considerably decrease da/*** effect of microstructure on da/dN and ΔK_(th)was discussed with the emphasis on the crack propagation path.

关键词： low carbon martensite duplex structure fatigue crack propagation rate threshold stress intensity range crack path

DYNAMIC ANALYSIS OF LARGE DEFORMATION OF RIGID-VISCOPLASTIC HARDENING SPHERICAL SHELLS IMPACTED BY A MISSILE

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Acta Mechanica Solida Sinica 1994年第1期7卷 68-79页

作者： Ning Jianguo(Peking university,Beijing 100871)Yang Guitong(Taiyuan university of Technology,Taiyuan 030024) Peking university Beijing 100871 China Taiyuan university of Technology Taiyuan 030024 China

This paper studies the dynamic behavior of large deformation of spherical shells impacted by a flat-nosed *** using isometric transformations,the deformation modes are *** the basis of Perzyna-Symonds viscoplastic constitutive equations,the motion equations of the shells are obtained by rigid- viscoplastic variational principle.A comparison made between the numerical results and experimental ones indicates that the two groups of results are in conformity with each other.

关键词： spherical shell impact isometric transformation rigid-viscoplasticity

Development of new geodetic coordinate datum management system

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中国有色金属学会会刊：英文版 2005年第S1期15卷 247-249页

作者： GENG Feng-kui (Hainan university,Haikou 570228,China) Hainan university Haikou 570228 China

Current situations of geodetic coordinate datum development procedures and management methods in China were presented. The precisions of astronomic geodetic network and space geodetic network were introduced. Geodetic datum requirements under the current and future new surveying technologies and their applications were discussed. The necessity for upgrading national astronomic geodetic network and development of a new open coordinate geodetic datum management method was investigated.

关键词： geodetic datum geodetic network management

NONOVERLAPPING DOMAIN DECOMPOSITION METHOD WITH MIXED ELEMENT FOR ELLIPTIC PROBLEMS

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Journal of Computational Mathematics 1996年第4期14卷 291-300页

作者： H.X. Rui(Mathematics Department, Shandong university, Jinan) 山东大学数学系山东济南

In this paper we consider the nonoverlapping domain decomposition method based on mixed element approximation for elliptic problems in two dimentional space. We give a kind of discrete domain decomposition iterative algorithm using mixed finite element, the subdomain problems of which can be implemented parallelly. We also give the existence, uniqueness and convergence of the approximate solution.

关键词： Zhang NONOVERLAPPING DOMAIN DECOMPOSITION METHOD WITH MIXED ELEMENT FOR ELLIPTIC PROBLEMS EV

TEXTURE DETERMINATION OF THIN FILM ZrO_2 BY ELECTRON DIFFRACTION

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Acta Metallurgica Sinica(English Letters) 1993年第12期6卷 472-473页

作者： WANG Yinghua Tsinghua university,Beijing,China Department of Materials Science and Engineering,Tsinghua university,Beijing 100084,China Tsinghua Univ Beijing China

A method for semi-quantitative determination of thin film texture using electron diffrac- tion is *** texture state of a zirconia thin film with a cubic structure has been determined in this way and is presented as an... 详细信息

关键词： texture thin film electron diffraction ZrO_2

Faber polynomials with applications to univalent functions with quasiconformal extensions

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Science China Mathematics 2009年第11期52卷 2121-2131页

作者： SHEN YuLiang Department of Mathematics, Soochow university, Suzhou 215006, China Department of Mathematics Soochow University Suzhou China

We obtain some convergence properties concerning Faber polynomials and apply them to studying univalent functions with quasiconformal extensions. In particular, by introducing an operator on the usual l2 space, we obt... 详细信息

关键词： univalent function quasiconformal mapping Faber polynomial Grunsky operator 30C62 30C55 47B37