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chinese Science Bulletin 2000年第11期45卷 1047-1052页

作者： GAO Jun, ZHANG Lifei & LIU Shengwei1. Institute of geology, chinese Academy of Geological Sciences, {2. 100037, china 2. department of geology, peking university, beijing 100871, chin Institute of geology Chinese Academy of Geological Sciences Beijing China department of geology Peking University Beijing China

The 40Ar/39Ar ages indicate that the eclogite facies rocks of the Hasiate slice in the western Tianshan Mountains were formed at the early stage of Devonian （401 Ma） and had been uplifted to the greenschist facies tectonic level in the middle stage of Devonian （381 Ma）. The formation and uplift of the blueschists of the Akesayi slice are constrained to the late stage of Devonian （370-364 Ma）. The different tectonic slices in the high-pressure metamorphic belt have experienced the different uplift history.

关键词： western Tianshan Mountains eclogite blueschist 40Ar/39Ar age.

THE PHYSICAL ENTROPY OF SINGLE CONSERVATION LAWS

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Journal of Computational Mathematics 1998年第5期16卷 437-444页

作者： (department of Mathematics, peking university,{2., china) 北京大学数学系北京

By means of the comparisons with the formulas in statistical mechanics and thermodynamics, in this paper it is demonstrated that for the single conservation law partial derivative(t)u + partial derivative(x)f(u) = 0, if the flux function f(u) is convex (or concave), then, the physical entropy is S = -f(u); Furthermore, if we assume this result can be generalized to any f(u) with two order continuous derivative, from the thermodynamical principle that the local entropy production must be non-negative, one entropy inequality is derived, by which the O.A. Olejnik's famous E- condition can be explained successfully in physics.

关键词： conservation laws entropy entropy production

Density-functional formula for strongly correlated systems

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Progress in Natural Science:Materials International 2005年第5期15卷 395-401页

作者： WANG Huaiyu1*, HAN Rushan2.and CHEN Nanxian1(1. department of Physics, Tsinghua university, {2. 100084, china 2. department of Physics, peking university, beijing 100871, china) department of Physics Tsinghua University Beijing 100084 China department of Physics Peking University Beijing 100871 China

Density functional method is applied for strongly correlated systems. Based on the assumption that the systems are composed of electrons in singly-occupied orbitals and those in doubly-occupied orbitals, a set of self-consistent equations are obtained by standard variation procedure. The equations consist of two parts. One part is to solve the wave functions of the electrons in singly-occupied orbitals and the other is to solve the wave functions of the electrons in doubly-occupied orbitals. The physical meanings of the terms appearing in the equations are discussed.

关键词： density-functional theory strongly correlated systems doubly-occupied orbital two-particle wave function self-consistent equations.

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,{2., 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

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,{2., 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

Research on Diageneses of Cambrian Shoal Facies Carbonate Rocks in the Xiadong Area, Hubei Province

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Acta Geologica Sinica(English Edition) 2001年第2期75卷 161-174页

作者： ZHANG Xiulian and JIANG Lingzhi department of geology,{2., beijing 100871 peking Univ Dept Geol Beijing 100871 Peoples R China

With continuous outcrops, developed shoal facies rocks, complete types of diagenesis and changeable diagenetic environments, Cambrian strata are well developed in the Xiadong area, Yichang, Hubei Province. Under the combined influence of numerous diageneses, secondary pores can be formed, which result in better reservoir properties of the rock strata.

关键词： diagenesis diagenetic facies interval diagenetic stage diagenetic environment

Diagenesis and Porosity of the Cambrian-Ordovician Carbonate Shoal Fades at Yangjiaping, Shimen, Hunan

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Acta Geologica Sinica(English Edition) 2000年第1期74卷 29-45,116-117页

作者： ZHANG Xiulian, WANG Yinghua and CHEN Xiaolong department of geology,{2., beijing 100871 peking Univ Dept Geol Beijing 100871 Peoples R China

Upper Cambrian-Lower Ordovician shoal-facies carbonate rocks are well developed in the Yangjiap-ing section, Shimen, Hunan, and their types are also highly varied. There are both monomictic shoal-facies rocks (e.g. sparite oolitic limestone and sparite calcarenite) and polymictic shoal-facies rocks (e.g. grainstone, whose grain types include sand- and pebble-sized fragments, bioclasts, oolites, algal mats etc.). What is different is that the Upper Cambrian shoal-facies rocks have been mostly strongly dolomitized into shoal-facies dolomite with various residual textures. This paper presents an in-depth study of various kinds of diagenesis and pore space evolution occurring in this section and suggests that the diagenetic sequences of shoal-facies rocks in the study area is dominantly of retrogressive type.

关键词： rock types dolomitization dissolution diagenetic sequence

THE FUNCTION d_k(n) AT CONSECUTIVE INTEGERS

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chinese Annals of Mathematics,Series B 1999年第4期20卷 473-478页

作者： MENG ZAIZHAO(department of Mathematics, peking university,{2., china) department of Mathematics Peking University Beijing 100871 China

Let dk(n) denote the k-fold iterated divisor function (k ≥ 2.. It is proved that for sufficiently large x) dk(n) = dk(n + 1) holds for >> x(log log x)-3 integers n ≤x.

关键词： Divisor function Multiplicative function Congruence

Phytolith assemblages and their implications from cal soils of Yingyang site in Dengfeng County, Henan Province

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chinese Science Bulletin 1997年第1期42卷 57-61页

作者： JIANG Qinhuadepartment of geology,{2., beijing 100871, china Depmment of geology Peking University Beijing China

THE central plain of china has been considered as the cradle of the chinese people, as is indicated by the abundant archaeological finds during the last 60 years. As a supplementary study to the archaeological excavation at Yingyang site of Dengfeng County, phytolith analysis was carried out. The Yingyang neolithic site is located in the south of the North china Plain and at the upper reaches of the Yinghe River, which belongs to the Huaihe drainage system, within

关键词： Yingyang site archaeological soils phytolith analysis paleoenvironment.

Anatomical reinvestigation of Archaeopteris macilenta from the Upper Devonian(Frasnian) of South china

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Journal of Systematics and Evolution 2011年第6期49卷 590-597页

作者： Yun GUO De-Ming WANG(Key Laboratory of Orogenic Belts and Crustal Evolution,department of geology,{2. university,beijing 100871,china) ( Key Laboratory of Orogenic Belts and Crustal Evolution Department of Geology Peking University Beijing 100871 China)

Archaeopteris macilenta is one of the most widespread plants in the Late *** on fossils from the Frasnian Huangjiadeng Formation,Yichang District of Hubei Province,for the first time we study in detail the anatomy of this progymnosperm plant in South *** axes are protostelic with three xylem sympodia and lack secondary *** axes are eustelic,bearing eight sympodia and a thin band of secondary *** symmetrical sympodia of mesarch primary xylem produce traces of appendages in a spiral *** macilenta and ***(***)are dominant in the Frasnian and Famennian,*** with these two species from other tectonic plates indicate consistent stelar *** spread,continuous occurrence,and identical anatomy during the Late Devonian indicate that Archaeopteris survived the Frasnian-Famennian extinction *** this time,endemic genera and cosmopolitan taxa,including Archaeopteris,suggest the palaeogeographic isolation of South china and certain associations with other plates.

关键词： anatomy Archaeopteris Late Devonian palaeogeography progymnosperms South china.