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Smooth solutions of non-linear stochastic partial differential equations driven by multiplicative noises

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Science china Mathematics 2010年第11期53卷 2949-2972页

作者： zhang XiCheng school of Mathematics and Statistics, wuhan university, wuhan 430072, china 1. school of Mathematics and Statistics Wuhan University Wuhan 430072 China

In this paper, we study the regularity of solutions of nonlinear stochastic partial differential equations (SPDEs) with multiplicative noises in the framework of Hilbert scales. Then we apply our abstract result to several typical nonlinear SPDEs such as stochastic Burgers and Ginzburg-Landau equations on the real line, stochastic 2D Navier-Stokes equations (SNSEs) in the whole space and a stochastic tamed 3D Navier-Stokes equation in the whole space, and obtain the existence of their smooth solutions respectively. In particular, we also get the existence of local smooth solutions for 3D SNSEs.

关键词： smooth solutions stochastic partial differential equations stochastic Navier-Stokes equations

Sol-gel Preparation Copper-cadmium Halide DopedPhotochromic Glass Coating on Plate Glass

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International Journal of Minerals,Metallurgy and Materials 2000年第1期14卷 34-37页

作者： ShiyongLuo Jiayun zhang Jixiang Liu Metallurgy school, university of Science and Technology Beijing, Beijing 100083, china wuhan university of Technology, wuhan 430070, china Univ Sci & Technol Beijing Met Sch Beijing 100083 Peoples R China wuhan Univ Technol Wuhan 430070 Peoples R China

Copper-cadmium halide doped photochromic glass coating on plate glass has been prepared by a sol-gel process. The sample shows reversible photochromic effect. The results of X-ray diffraction (XRD) and infrared (IR) spectrum investigations indicate that the photochromic phase of tile coating is CuBr_xCl_(1-x), solid solution, and that the structure network of the coating is connected with the bonds of Si-O-Si, Si-O-B and Si-O-Al.

关键词： photochromic glass coating sol-gel photochromic phase, structure network

South china's Gondwana connection in the Paleozoic:Paleomagnetic evidence

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Progress in Natural Science:Materials International 2004年第1期14卷 86-91页

作者： zhang Shihong*(school of Earth Sciences and Resources, china university of geosciences, Beijing 100083, china) china Univ Geosci Sch Earth Sci & Resources Beijing 100083 Peoples R China

The reconstruction in which the South china Block (SCB) lies along the Great India Australia region of Gondwana margin is tested by using existing Paleozoic paleomagnetic data. Under the proposed reconstruction, all six high quality paleopoles from the SCB between the Early Cambrian and late Early Devonian (～400 Ma) are in good agreement with coeval paleopoles from Gondwana. Thereafter, the apparent polar wander paths for the SCB and Gondwana diverge markedly. This indicates that the SCB had been part of Gondwana and the connection was intact from at least Early Cambrian until late Early Devonian, but they began to separate by late Middle Devonian (～375 Ma).

关键词： South china block Gondwana paleomagnetism reconstruction

Evolutionary patterns of Productida (Brachiopoda) morphology during the Permian in South china

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Science china Earth Sciences 2008年第11期51卷 1589-1600页

作者： zhang Yang1 & HE WeiHong1,2 1 Faculty of Earth Sciences, china university of geosciences, wuhan 43.074, china 2 Key Laboratory of Biogeology and Environmental Geology of Ministry of Education, china university of geosciences, wuhan 43.074, china 1. Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China 2. Key Laboratory of Biogeology and Environmental Geology of Ministry of Education China University of Geosciences Wuhan 430074 China

The evolutionary patterns of Productida (brachiopod) morphology throughout the Permian show that while the percentage proportion of Productida (brachiopod) with strongly concentric and radial ornamentation declined from the Cisuralian to the Guadalupian, and then increased towards the Changhsingian via Wuchiapingian, the percentage proportion of Productida (brachiopod) with fine concentric and radial ornamentation distinctly increased from the Cisuralian to the Guadalupian, slightly declined towards the Wuchiapingian, and then increased towards the Changhsingian. From the Cisuralian to the Changhsingian, the percentage proportion of brachiopods with spinose ornamentation shows a persistent declining trend. The shell size generally indicates a miniaturization trend at species level during the Wuchiapingian to Changhsingian (including the transitional bed). These evolutionary patterns of brachiopod ornamentation and size are possibly related to the anoxia, food shortage, sea-level fluctuation, and change of substrate in the Permian (including the Permian-Triassic transitional interval) in South china.

关键词： brachiopod ornamentation size Permian South china

STUDY OF HYDRODYNAMIC FORCES OF SHIPS IN NARROW WATERWAY

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Journal of Hydrodynamics 2003年第4期15卷 113-117页

作者： zhang Xie-dong, Wu Xiu-heng school of Transportation, wuhan university of Technology, wuhan 430063, china school of Transportation Wuhan University of Technology Wuhan 430063 China

The collision of ships in narrow waterway may occur for a variety of *** hydrodynamic forces between two ships change the maneuvering characteristics of ships *** based on the boundary element method, this paper proposes a calculation method for hydrodynamicinteraction forces between ships under meeting and passing conditions in narrow waterway. Theresults from this method are compared with the existing results obtained from other theoreticalapproaches, and they are in good agreement.

关键词： collision of ships narrow waterway hydro-dynamic interaction boundaryelement method

Geochemical characteristics and tectonic implications of HP-UHP eclogites and blueschists in southwestern Tianshan, china

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Progress in Natural Science:Materials International 2006年第6期16卷 624-632页

作者： AI Yongliang, zhang Lifei, LI Xuping and QU Junfeng (MOE Key Laboratory of Orogenic Belt and Crust Evolution, school of Earth and Space Sciences, Peking university, Beijing 100871, china school of geosciences and Resources, china university of geosciences, Beijing 100083, china) [a]MOE Key Laboratory of Orogenic Belt and Crust Evolution School of Earth and Space Sciences Peking University Beijing China [b]school of geosciences and Resources China University of Geosciences Beijing China

Four rock assemblages in correspondence with two different tectonic settings have been recognized in the NEE-SWW extending HP-UHP metamorphic belt in southwestern Tianshan, northwest china. Eclogite assemblage EC1 is geochemically akin to alkaline within-plate oceanic island basalt (OIB). EC2 shows affinity to enriched mid-oceanic ridge basalt (EMORB). Rare earth element (REE) and other immobile trace element characteristics of blueschist assemblage BS1 resemble those of normal mid-oceanic ridge basalt (NMORB). These three assemblages are likely formed on a seamount setting, and the prevalent presence of carbonate minerals and om-phacite quartzite stripes/gobbets suggests ancient pelagic sediments including marls are probably developed upon the basaltic seamount. Whereas the geochemical characteristics of BS2 assemblage are of volcanic arc basalt-type. The seamount with the pelagic sediments on it is brought into the subduction zone, and volcanic arc basalts formed on the active continental margin and trench sediments are eroded and enwrapped in the subducting mass, they are altogether subjected to high to ultrahigh pressure metamorphism and subsequent exhumation towards surface. The HP-UHP metamorphic belt is thus interpreted as a subduct ion-accretionary complex formed by tectonic juxtaposition and imbrication of seamount, seafloor, trench and volcanic arc sequences during oceanic crust subduction.

关键词： southwestern Tianshan HP-UHP metamorphic belt snbduction-accretion complex trace element geochemistry.

Influence of Acetic Acid on Dynamic Behavior of Hydrolazation and Film Forming of Organosilane

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Journal of wuhan university of Technology(Materials Science) 2009年第4期24卷 546-551页

作者：杨丽霞 school of Materials Chemistry and Engineering China University of Geosciences

The influence of acetic acid on dynamic behavior of hydrolazation and film forming of an expoxy-silane compound （y-GPS） was investigated by conductivity meter, IR and AFM. The experimental results show that there is an optimal pH value（pH=4-5） for hydrolysis of silane solution, and with the prolongation of hydrolytic time, the promotion of acetic acid on the hydrolyzation of silane solution become more obvious. During the adsorption and film forming process, acetic acid could promote the formation of Si-O-Fe bond, which activates hydroxyl group of silanol unit and facilitates this hydroxyl group to react with adjacent silanol unit forming linear condensation polymers.

关键词： organosilane hydrolyzation film forming acetic acid

Fault System,Deformation Style and Development Mechanism of the Bachu Uplift,Tarim Basin

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Journal of Earth Science 2012年第4期23卷 529-541页

作者：佟殿君张俊霞阳怀忠胡德胜任建业 Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education China University of Geosciences school of Economics and Management China University of Geosciences Beijing Research Institute CNOOC Zhanjiang Branch CNOOC Structral Research Center of Oil&Gas Bearing Basin Ministry of EducationChina University of Geosciences

The Bachu （巴楚） uplift is one of the most active tectonic regions nowadays in the Tarim basin, which is also a faulted block uplift that was intensively active during the Cenozoic. This study was based primarily on the geological structure interpretation of seismic profiles, applying the theories and methods of basin dynamics, structural analysis and tectono-stratigraphic analysis, the geometry and kinematics features of the fault systems in the Bachn uplift were analyzed in detail. Our study shows that each fault belt is mainly characterized by compression and overthrusting, most of the faults initiated and activated during the Mid-Late Himalayan period, and that the general structural styles of the Bachu uplift were basement-involved pop-up thrust faulted block uplift, of which the southern margin was covered by the large-scale decollement fault system. The basement-involved structures widely developed in the higher position of the basement uplift, while decollement fault system developed mainly at the position with gypsum mudstone. The evolution process of Bachu uplift included back-bulge slope of the peripheral foreland basin in Mid-Late Caledonian, forebulge in HercynianYanshanian and the latest compressional faulted block uplift in Mid-Late Himalayan. Meanwhile,the study also suggests that the formation, reconstruction and stabilization of the uplift were controlled by the development and evolution of fault systems clearly. In the early forebulge stage, it was mainly presented as flexural deformation without the developing of thrust faults in the Bachu area; to the late stage, under the influence of violent lateral compression deformation, the faulted block uplift formed finally.

关键词： fault system structural style structural evolution Bachu uplift Tarim basin.

CHARACTERIZATION OF REGENERATED CELLULOSE MEMBRANES HYDROLYZED FROM CELLULOSE ACETATE

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Chinese Journal of Polymer Science 2002年第4期20卷 369-375页

作者： Yun Chen Xiao-peng Xiong Guang Yang Li-na zhang Sen-lin Lei Hui Liang Electron Microscope Lab of Medical school, wuhan university wuhan 430072, china College of Chemistry and Molecular Sciences, wuhan university, wuhan 430072, china wuhan Univ Coll Chem & Mol Sci Wuhan 430072 Peoples R China wuhan Univ Sch Med Electron Microscope Lab Wuhan 430072 Peoples R China

A series of cellulose acetate membranes were prepared by using formamide as additive, and then were hydrolyzed in 4 wt% aqueous NaOH solution for 8 h to obtain regenerated cellulose membranes. The dependence of degree of substitution, structure, porous properties, solubility and thermal stability on hydrolysis time was studied by chemical titration, Fourier transform infrared spectroscopy, scanning electron microscopy, wide-angle X-ray diffraction, and differential scanning calorimetry, respectively. The results indicated that the pore size of the regenerated cellulose membranes was slightly smaller than that of cellulose acetate membrane, while solvent-resistance, crystallinity and thermostability were significantly improved. This work provides a simple way to prepare the porous cellulose membranes, which not only kept the good pore characteristics of cellulose acetate membranes, but also possessed solvent-resistance, high crystallinity and thermostability. Therefore, the application range of cellulose acetate membranes can be expanded.

关键词： hydrolysis cellulose acetate thermal stability regenerated cellulose membrane pore size solvent-resistance SEM