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The tectonic settings and seismogenic tectonics of the M5.7 Jiujiang earthquake in 2005,Jiangxi Province,China

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Science China Earth Sciences 2008年第5期51卷 640-653页

作者： LI ChuanYou1, ZENG XinFu2 & ZHANG JianXi3.1 institute of Geology, China Earthquake Administration, beijing 10002., China 2 Jiangxi Earthquake Administration, Nanchang 3.003., China 3.beijing Earthquake Administration, beijing 100080, China 1. institute of Geology China Earthquake Administration Beijing 100029 China 2. Jiangxi Earthquake Administration Nanchang 330039 China 3. beijing Earthquake Administration Beijing 100080 China

The M5.7 Jiujiang earthquake in 2005 was a mid-strong one, stronger than expected to occur in the region. This paper discusses the neo-tectonic settings of this earthquake, and it is thought that the earthquake region is located in the transitional belt, a potential area inducing weak to moderately strong earthquakes, between two large different tectonic units. The results of the reconnaissance work and on-the-spot investigation after earthquake indicate that the occurrence of the M5.7 Jiujiang earth- quake is closely related with the NE-trending fault on the western margin of Ruichang Basin. From its controlling to the landforms and Quaternary depositions, geological profiles, ESR dating, etc., the ac- tivity of the Dingjiashan-Langjunshan fault bounding the basin is discussed. It suggests that this fault displays an active one in Middle Pleistocene by the outcrop. Based on the activity of the fault, and the direction and location of the ground fissures, the isoseismal lines and the nodal plane of the focal mechanism solution, it is inferred that the Dingjiashan-Langjunshan fault is the seismogenic tectonics of the M5.7 Jiujiang earthquake, and the intersection point between this fault and the active NW ones is the possible origin of location of this earthquake. Our study shows that this earthquake is not an event exceeding expectation, and that the active and invisible characteristics of the causative fault are typical in the eastern area of China.

关键词： Jiujiang earthquake tectonic settings Dingjiashan-Langjunshan fault activity seismogenic tectonics

Preparation of a Novel Micro/nano Tubes via Electrospun Fiber as a Template

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Journal of Materials Science & Technology 2004年第5期20卷 613-616页

作者： Taiqi LIUSchool of Materials and Chemical Engineering, beijing institute of Petro-chemical Technology, beijing 102617, China Sch. of Mat. and Chem. Eng. Beijing Inst. of Petrochem. Technol. Beijing 102617 China

Poly (para-xylylene) hollow fibers with inner diameters can be prepared via template fibers electrospun from solutions. The PPX is deposited from the vapor phase and the template fiber is selectively removed by heat treatment or solvent extraction. The PPX is partially crystalline and the crystal modification depending on the route is used to extract the template fiber. The thermal stability of the hollow fibers is only slightly reduced relative to the bulk material and the same holds for the UV-stability.

关键词： Electrospinning Fiber Chemical vapor deposition Physical vapor deposition Crystal Conductivity

Mechanism of Cathode Process of B(Ⅲ) in LiF-NaF-KBF_4 Meltby Electrochemical Titration Technique

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International Journal of Minerals,Metallurgy and Materials 1998年第4期12卷 203-207页

作者： Qingrong Shi Xindong Wang Lianyu Yuan Shuzhen Duan(applied Science School, University of Science and Technology beijing, beijing 100083. China) applied Science School University of Science and Technology Beijing Beijing 100083 China

The mechanism of cathode process of B(Ⅲ) at molybdenum and platinum electrodes in LiF-NaF-KBF4melt was studied and the transferred electron number of the reaction was calculated by means of cyclic *** effect of adsorption of electroactive component on the electrochemical response (e. g., the voltammetric i─Ecurves) was analyzed and discussed. The 'electrochemical spectra' for linear sweep voltammetry was used to elucidate the electrode reaction accompanied by a following transform process. The results show that the reduction ofB(Ⅲ) to B(0) proceeds in reversible one step three-electron reaction and the cathode process of B(Ⅲ) is affected byproduct adsorbed strongly at the electrode surface. It is assumed that the reduction and deposition of B(Ⅲ) at molybdenum and platinum electrodes proceed in two kinds of mechanism： (1) B(Ⅲ)＋ 3. = Bads→ B (surface diffusiondeposition mechanism) and (2) B(Ⅲ) ＋ 3. = B (direct deposition mechanism).

关键词： boron ions cathode process cyclic voltammetry fluoride melt

Crystallization Mechanism of Na_2O-CaO-Al_2O_3.SiO_2-F Glass Containing Cr_2O_3

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International Journal of Minerals,Metallurgy and Materials 1999年第3期13卷 214-218页

作者： Lidong Teng Fuming Wang Wenchao Li(Department of inorganic Materials, Shandong institute of Light Industry, Jinan 250100, China)(applied Science School, University of Science and Technology beijing, beijing 100083. China) Department of Inorganic Materials Shandong Institute of Light Industry Jinan 250100 China applied Science School University of Science and Technology Beijing Beijing 100083 China

The effect of Cr2O3.on the nucleation and crystallization of Na2O-CaO-Al2O3.SiO2-F- glass has been investigated by means of ESR(Electron Spin Resonance), SEM(Scanning Electron Microscope), EDS(Energy Dispersive Specrometer) and so on. Computer pattern recognition is applied to optimize the heat-treatment schedules. The experimental results show that the base glass containing more than 1 .5 % (mass fraction) Cr2O3.can be nucleated internally and converted to spheroidal crystal glass materials. The spheroidal crystal consisted of fibrous wollastonite crystals radiating from a center. The residual glass phase filled in the interstices between the fibers and between the spherulites. During heat treatment process, the valence states ofchromium changed from Cr6- to Cr3., and the Cr-spinel solidsolution [CaCr2O4] precipitated followed this valence change. At the primary stage of crystallization, the Cr-spinel could act as a nucleating center on which the principal or}stalline phase β-CaSiO3.grew epitaxially.

关键词： crystallized glass Na_2O-CaO-Al_2O_3.SiO_2 Cr_2O_3 pattern recognition

Structure and Formative Mechanism of Black Patina on Bronze Mirrors

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International Journal of Minerals,Metallurgy and Materials 1998年第3期12卷 147-155页

作者： Zhaozeng Ma Ling Du Xiulan Yin Lianji Jin Chunying Fang(applied Science School, University of Science and Technology beijing, beijing 100083. China) applied Science School University of Science and Technology Beijing Beijing 100083 China

The formation of the black patina induced by soil humic asid under different conditions was studied, theblack, grey and brown colored shiny surfaces prepared in laboratory were analyzed. As a result the formation oftin-rich shiny black surface on bronze mirrors is the product of soil corrosion of the bronze mirrors. The patina isformed by reection between the alloy and the humic acid in soil, and leaching of copper and lead oxides through along period time when the mirrors were buried under the ground leaving a dense compact corrosion-resistant layerconsisted predominantly of stannic oxide microcrystal.

关键词： black patina on ancient bronze mirror humic acid soil corrosion, SnO_2 microcrystal

Design of secure operating systems with high security levels

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Science in China(Series F) 2007年第3期50卷 399-418页

作者： QING SiHan1,2 & SHEN ChangXiang3.1 institute of Software, Chinese Academy of Sciences, beijing 100080, China 2 School of Software and Microelectronics, Peking University, beijing 102600, China 3.institute of Computing Technology, Navy, beijing 100841, China 1. institute of Software Chinese Academy of Sciences Beijing 100080 China 2. School of Software and Microelectronics Peking University Beijing 102600 China 3. institute of Computing Technology Navy Beijing 100841 China

Numerous Internet security incidents have shown that support from secure operating systems is paramount to fighting threats posed by modern computing environments. Based on the requirements of the relevant national and international standards and criteria, in combination with our experience in the design and development of the ANSHENG v4.0 secure operating system with high security level （hereafter simply referred to as ANSHENG OS）, this paper addresses the following key issues in the design of secure operating systems with high security levels： security architecture, security policy models, and covert channel analysis. The design principles of security architecture and three basic security models： confidentiality, integrity, and privilege control models are discussed, respectively. Three novel security models and new security architecture are proposed. The prominent features of these proposals, as well as their applications to the ANSHENG OS, are elaborated. Cover channel analysis （CCA） is a well-known hard problem in the design of secure operating systems with high security levels since to date it lacks a sound theoretical basis and systematic analysis approach. In order to resolve the fundamental difficulties of CCA, we have set up a sound theoretical basis for completeness of covert channel identification and have proposed a unified framework for covert channel identification and an efficient backward tracking search method. The successful application of our new proposals to the ANSHENG OS has shown that it can help ease and speedup the entire CCA process.

关键词： secure operating systems with high security levels architecture security model covert channel analysis

Median cross-validation criterion

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Chinese Science Bulletin 1997年第23期42卷 1956-1959页

作者： YANG YingDepartment of applied Mathematics, Tsinghua University, beijing 100084, China Department of applied Mathematics Tsinghua University Beijing China

CONSIDER the nonparametric median regression model Yni = g (xni) + εni, 1≤i≤n （1）where g: [0, 1]|→R is an unknown function of interest; {xni, 1≤i≤n} is the fixed design pointsin the interval [0, 1]; {εni, 1≤i≤n} is a triangular array of row iid random variables having medi-an zero, and {Yni, 1≤i≤n} is the observation. For each x∈[0, 1], n≥1, let Dnj（x） denotethe jth nearest neighber of x, j=1, 2,…, n, i. e. {Dn1（x）, Dn2（x）,…, Dnn（x）} is a trans-position of {xn1, xn2,…, xnn} satisfying |Dn1（x）-x|≤|Dn2（x）-x|≤…≤|Dnn（x）-x|.The tie is broken by the chronological order. The

关键词： median cross validation Bahadur’s representation asymptotic oplimality.

Prediction of Enthalpies of Fusion for Divalent Rare Earth Halides Based on Modeling by Artificial Neural Networks and Pattern Recognition

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 24-26页

作者： Yimin Sun Zhiyu Qiao Minghong He(applied Science School, University of Science & Technology beijing, beijing 100083. China)(National Natural Science Foundation of China, beijing 100083. China) applied Science School University of Science and Technology Beijing Beijing 100083 China National Natural Science Foundation of China Beijing 100083 China

The artificial neural network (ANN) and the pattern recognition were applied to study the correlation of enthalpies of fusion for divalent rare earth halides with their microstructural parameters,such as ionic radius and electronegativity. The model,represented by a back-propagation netal network, was trained with a 12.set of published data for divalent rare earth halides and then was used to predict the unknown ones. Also the criterion equations were ptesented to determine the enthalpies of fuSion for divalent rare earth halides using pattern recognition in mis work. The results from the model in ANN and criterion equations are in very good agreement with reference data.

关键词： BP neural network pattern recognition enthalpy of fusion divalent rare earth halides microstructural parameters

DECAY OF GLOBAL SOLUTIONS OF TWO NONLINEAR EVOLUTION EQUATIONS

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Acta Mathematicae Applicatae Sinica 1997年第1期13卷 23-32页

作者： GUO BOLING ZHANG LINGHAI(institute of applied Physics and Computational Mathematics, beijing 100088, China) institute of applied Physics and Computational Mathematics Beijing China

We study the decay of solutions of two nonlinear evolution equations: the Benjamin-OnoBurgers and the Schrodinger-Burgers equations. We establish sharp rates of L2 decay of global solutions to these problems, with initial data Uo(x)∈L1∩L2. The decay results of the solutions follow from the a priori L2 integral estimstes and the Fourier transform. The standard argument relies on a technique that involves the splitting of the phase space into two time-dependent subdomains.

关键词： Decay estimates nonlinear evolution equations