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PROGRESSING WAVE SOLUTIONS TO QUASI-LINEAR SYSTEMS MIXED PROBLEMS

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Chinese Annals of Mathematics,Series B 1994年第4期15卷 401-420页

作者： WANG WEIKE(Department of Mathematics,wuhan university,wuhan 430072,china.) 武汉大学数学系湖北武汉 430072

The author studies the technique of paradifferential operator defined on a space of conormaldistribution with three indeces,and then use this technique to prove that a progressing wavewhich hits the boundary is reflec... 详细信息

关键词： Quasi-linear system Mixed problem Conormal distribution Tangential Paradifferential operator Reflection of progressing wave.

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

Gradient analysis of landscape spatial and temporal pattern changes in Beijing metropolitan area

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Science china(Technological Sciences) 2010年第S1期53卷 91-98页

作者： YANG YeTao1,ZHOU QiMing2,GONG JianYa3 & WANG YingYing4 1 Institute of Geophysics and Geomatics,china university of geosciences,wuhan 4.0074.china 2 Department of Geography,Hong Kong Baptist university,Hong Kong 3 State Key Laboratory of Information Engineering in Surveying,Mapping and Remote Sensing,wuhan university,wuhan 4.0074.china 4 Hubei Provincial Bureau of Meteorology,wuhan 4.0074.china Institute of Geophysics and Geomatics China University of Geosciences Wuhan China Department of Geography Hong Kong Baptist University Hong Kong China State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan China Hubei Provincial Bureau of Meteorology Wuhan China

The gradient based landscape metrics analysis is now widely used to study the landscape pattern changes in respond to the *** order to discover the trend of spatio-temporal changes in Beijing metropolitan area during the past 15 years,several landscape metrics are computed using a moving window along a 96.km long transect across Beijing metropolitan area from west to ***,the spatial extent of sub-landscape,which is determined by the moving window’s size,is profoundly *** results show that the metrics varies smoothly and regularly along the selected transect when the window size is greater than 6.km×6.km,and irregularly fluctuated for the smaller window size,that the spatial and temporal landscape characteristics of Beijing city match the hypothetical framework of spatio-temporal urban sprawl in the form of alternating processes of diffusion and coalescence well,and that some new trends of the urban sprawl style in Beijing metropolitan area,such as leap-frog manner,are also detected by the gradient landscape analysis.

关键词： gradient analysis landscape metrics spatio-temporal urban expansion multi-extent

Geothermal and fluid flowing simulation of ore-forming antimony deposits in Xikuangshan

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Science china Earth Sciences 2006年第8期49卷 862-871页

作者： YANG Ruiyan1,2, MA Dongsheng2, BAO Zhengyu3, PAN Jiayong2, CAO Shuanglin2 & XIA Fei2 1. School of Mathematics and Physics, china university of geosciences, wuhan 4.0074. china 2. State Key Laboratory for Research of Mineral Deposits, Nanjing university, Nanjing 210093, china 3. Faculty of Earth Sciences, china university of geosciences, wuhan 4.0074. china School of Mathematics and Physics China University of Geosciences Wuhan China State Key Laboratory for Research of Mineral Deposits Nanjing University Nanjing 210093 China Faculty of Earth Sciences China University of Geosciences Wuhan China

The Xikuangshan Antimony Deposit located in the Mid-Hunan Basin, china, is the larg- est antimony deposit in the world. Based on the hydrogeological and geochemical data collected from four sections, Xikuangshan-Dajienao (AO), Xikuangshan-Dashengshan (BO), Xikuang- shan-Longshan (CO) and Dafengshan (DO) in the Basin, an advanced metallogenic model related to deep-cyclic meteoric water of Xikuangshan Antimony Deposit is put forward in this paper using a model of heat-gravity-driving fluid flow transportation. The simulation results show that the ore-forming fluid of the deposit mainly comes from the Dashengshan and Longshan areas where BO and CO sections are located if the overall basin keeps a constant atmospheric precipitation and infiltration rate during mineralization, and that the average transportation speed of the ore-forming fluids is about 0.2―0.4 m/a.

关键词： ore-forming fluid, numerical simulation, geothermal field, geofluid transport, Xikuangshan, antimony deposits.

Magnetic and mineralogical characteristics of reservoir rocks in the Yakela oil field, northern Tarim Basin and their implications for magnetic detection of oil and gas accumulations

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Chinese Science Bulletin 1999年第2期44卷 174-177页

作者： LIU Qingsheng LIU ShugerDepartment of Applied Geophysics, china university of geosciences, wuhan 4.0074. china The State Key Laboratory of Oil/Gas Reservoir Geology and Exploitation of china, Chengdu Institute of TechnologyChengdu 6.0059, china Department of Applied Geophysics China University of Geosciences Wuhan China The State Key Laboratory of Oil/Gas Reservoir Geology and Erploitation of china Chengdu Institute of Technology Chengdu China

The evidence about hydrocarbon migration within reservoir rocks in two wells has been obtained according to results of magnetic and mineralogical analysis of the Kapushaliang Group reservoir rocks from wells S15 and S4 located at the Yakela oil field, Tarim Basin. Results show that the secondary alteration associated with oil and gas accumulations above oil and gas field is predominantly magnetite mineralization, and that sulfur alteration occurs commonly at oil-water boundary and their products are generally pyrite and pyrrhotite, except for magnetite alteration which is closely related with hydrodynamical conditions in situ. The spherical magnetite grains of cauliflower microtexture on surface extracted from oil-bearing cores are secondary magnetite related with hydrocarbon microseepage and their diameters are usually less than 50 μm.

关键词： hydrocarbon microseepage magnetic mineralogy magnetic hysteresis loop thermal magnetic analysis reservoir petrophysics.

SOME BOUNDARY INCREASING PROPERTIES OF HARMONIC FUNCTIONS IN LIPSCHITZ DOMAIN

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Chinese Annals of Mathematics,Series B 1996年第2期17卷 159-166页

作者： ZHANG YIPING Department of Mathematics, wuhan university, wuhan 430072, china.Project supported by the National Natural Science Foundation of china. Department of Mathematics Wuhan University Wuhan 430072 China

The object of this paper is to study the non-tangential increasing properties of positiveharmonic function u in Lipschitz domain by means of Martin representation theory. A necessaryand sufficient condition of the control of growth of u near any fixed boundary point is obtained.It is shown that the non-tangential increasing degree of u near a boundary point is exactlythe local degree of its representation measure with respect to the harmonic measure. Someexamples are given.

关键词： Martin representation Harmonic function Harmonic measure

A novel method of systematic error compensation for a position and orientation system

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Progress in Natural Science:Materials International 2008年第8期18卷 953-963页

作者： Xiuxiao Yuan* School of Remote Sensing and Information Engineering, wuhan university, wuhan 430079, china School of Remote Sensing and Information Engineering Wuhan University Wuhan 430079 China

A novel method is introduced for self-calibration and elimination of systematic errors for a position and orientation system (POS). The method uses a combined bundle block adjustment with POS data (named the POS-supported bundle block adjustment) without a calibration field. On the basis of delivering strict observation equations for POS data, the specific scheme of compensating the translation and drift systematic errors in a POS is given, and a prototype system WuCAPS is developed. The effects of eliminating POS systematic errors using the POS-supported bundle block adjustment for different ground control conditions are tested using two sets of actual aerial photos. The first set was taken over a flat region in the suburbs of the city of Yingkou in china and tested at a scale of 1:2500. The second set was taken over a high mountainous region in the desert region of Xinjiang in china and tested at a scale of 1:32,000. The empirical results verified that the POS systematic errors can be completely eliminated and the photo elements of exterior orientation obtained by the POS-supported bundle block adjustment can satisfy the requirements of aerial photogrammetric topographic mapping when four full ground control points (GCPs) are emplaced in the corners of the adjustment block for large-scale images of flat regions, but only one full GCP emplaced in the center of the adjustment block is needed for medium-small scale images of mountainous regions. This not only demonstrates the validity of the established mathematical model and the feasibility of the method proposed in this paper, but also avoids the use of a special calibration field. Therefore, it can simplify the existing POS operation rules and dramatically save on practical application costs, laying the theoretical foundation for widespread use of POS.

关键词： Position and orientation system (POS) Systematic error POS-supported bundle block adjustment Self-calibration Accuracy

Age of Yingfeng rapakivi granite pluton on the north flank of Qaidam and its geological significance

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Science china Earth Sciences 2004年第4期47卷 357-365页

作者： XIAO Qinghui1,2, LU Xinxiang1,3, WANG Fei4, SUN Yangui5, WEI Xiangdong3 & XING Zuoyun6.1. Division of Granite Geology, china Geological Survey, Yichang 443003, china 2. Information Center of Ministry of Land and Resources, Beijing 100812, china 3. Geological Survey of Henan Province and Institute of Geological Research of Henan Province, Zhengzhou 450053, china 4. Geological Institute, china Seismological Bureau, Beijing 100029, china 5. Geological Survey Institute of Qinghai Province, Xining 810032, china 6. china university of geosciences, wuhan 4.0074. china Division of Granite Geology China Geological Survey Yichang China Information Center of Ministry of Land and Resources Beijing China Geological Survey of Henan Province and Institute of Geological Research of Henan Province Zhengzhou China Geological Institute China Seismological Bureau Beijing China Geological Survey Institute of Qinghai Province Xining China china university of geosciences Wuhan China

The Yingfeng rapakivi granite on the north flank of Qaidam is a newly discovered Proterozoic rapakivi pluton in china, which was found after the discovery of Shachang rapakivi in Miyun County, Beijing and Kuandian rapakivi in Jilin Province. Yingfeng rapakivi pluton is ex-posed on the north side of the suture belt between Qinling-Kunlun orogenic belt and North china plate. U-Pb zircon isotopic dating and Ar-Ar isotopic dating of both hornblende and K-feldspar from the Yingfeng rapakivi granite have been conducted. The results show that the age of (1776.33)Ma at the upper intercept in Concorde diagram represents the age of formation of the plu-ton, whereas the age of (526.281) Ma at the lower intercept and Ar-Ar mineral dating of horn-blende and K-feldspar correspond to the age of a later event affecting the pluton, suggesting that Yingfeng pluton has ever been affected by strong regional Caledonian-Hercynian tectonic movement after its formation. The discovery of middle Proterozoic Yingfeng rapakivi granite pro-vides a petrologic evidence for the timing of cratonization of both the continental crust basement in western china and the basement of the North china plate and for a rifting event taking place in the mid-Proterozoic, suggesting that an amalgamation of ancient china continents had ever happened during the L liang Movement?between the early Proterozoic and the mid-Proterozoic.

关键词： rapakivi, U-Pb dating, Ar-Ar dating, Kunlun-Qinling orogenic belt.

Pathways of birnessite formation in alkali medium

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Science china Earth Sciences 2005年第9期48卷 1438-1451页

作者： FENG Xionghan1, TAN Wenfeng1, LIU Fan1, HUANG Qiaoyun1 & LIU Xiangwen2 1. College of Resources and Environment, Huazhong Agricultural university, wuhan 430070, china 2. Testing Center, china university of geosciences,{6. College of Resources and Environment Huazhong Agricultural University Wuhan China Testing Center China University of Geosciences Wuhan China

Birnessite is a common weathering and oxidation product of manganese-bearing rocks. An O2 oxidation procedure of Mn(OH)2 in the alkali medium has been used to synthesize birnessite. Fast and powder X-ray diffraction (XRD), transmission electron microscopy (TEM), electron diffraction (ED), energy dispersed X-ray analysis (EDAX), infrared spectroscopy (IR) techniques and chemical composition analysis, Eh-pH equilibrium diagram approaches were employed to investigate the reaction process and pathways of birnessite formation. Results showed that the process of the birnessite formation could be divided into four stages: (1) forma- tion stage for hausmannite and feitknechtite, (2) stage of transformation of hausmannite and feitknechtite to buserite, (3) buserite crystal growing stage, and (4) stage of conversion of buser- ite into birnessite. Mn(OH)2 was mainly present as amorphous state only for a short initial time of oxidation reaction. In the oxidation process, buserite formed following two pathways by recrys- tallization after dissolution of the intermediates, and the transformations of the minerals de- pended on the Eh determined by the dissolved O2 concentration on their surfaces. The results are fundamental in further exploration on the mechanism of birnessite formation in the alkali medium. A great practical significance would also be expected with respect to the areas of mate- rial sciences.

关键词： birnessite, pathway of formation, reaction process, Eh-pH diagram, hausmannite, feitknechtite.