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Integrated Water and CGE Model of the Impacts of Water Policy on the Beijing's Economy and Output

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Chinese Journal of Population,Resources and Environment 2010年第2期8卷 61-67页

作者： Xia Jun deng qun sun Yangbo Key Lab of Water Cycle and Related Surface Process Institute of Geographical Sciences and Natural Resources Chinese Academy of Sciences Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100101 China

The article used general equilibrium model to analyze the change of gross domestic product and industry output affected by water resources policies in Beijing City by using GEMPACK soft *** article researches on rules of water supply and demand,evaluating water resources,building water resources input and output table,establishing water computable general equilibrium model and stimulating water *** stimulation gives a scenario that increases water price by 10%.The result shows the following ***,water resources policy infects gross domestic product and industry output in different *** are different behaviors in different industries as to the water policy. Agriculture industry has the same tendency as water price change and it has more sensitive to water quantity than to water *** basic energy industries such as oil and chemistry and gas,they show diversity *** to some high water consumer industry such as paper and textile etc.,water resource economic policy can infect them greatly and can promote them to accomplish more water-saving *** water and construction and service industries show the same tendency as to water ***,government should pay more attention to water resource policy by macro economic *** simulation also shows that the output and supply and consumer price change more than expect as to water policy in a free market economic in water *** as to a government policy maker,one should be more carefully and prepare suitable forecast and plan to water policy and its negative impact.

关键词： water resource policy analysis CGE model Beijing input-output table general equilibrium

Second-order random interfacial wave solutions for two-layer fluid with a free surface

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Acta Oceanologica Sinica 2006年第1期25卷 15-20页

作者： SONG Jinbao sun qun Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China

A previous study （Song. 2004. Geophys Res Lett, 31 （15）：L15302） of the second-order solutions for random interracial waves is extended in a constant depth, two-layer fluid system with a rigid lid is extended into a more general case of two-layer fluid with a top free surface. The rigid boundary condition on the upper surface is replaced by the kinematical and dynamical boundary conditions of a free surface, and the equations describing the random displacements of free surface, density-interface and the associated velocity potentials in the two-layer fluid are solved to the second order using the same expansion technology as that of Song （2004. Geophys Res Lett, 31 （15）：L15302）. The results show that the interface and the surface will oscillate synchronously, and the wave fields to the first-order both at the free surface and at the density-interface are made up of a linear superposition of many waves with different amplitudes, wave numbers and frequencies. The second-order solutions describe the second-order wave-wave interactions of the surface wave components, the interface wave components and among the surface and the interface wave components. The extended solutions also include special cases obtained by Thorpe for progressive interracial waves （Thorpe. *** R Soc London, 263A：563～614） and standing interracial waves （Thorpe. 1968b. J Fluid Mech, 32：489-528） for the two-layer fluid with a top free surface. Moreover, the solutions reduce to those derived for random surface waves by Sharma and Dean （*** Engineering Rep 20） if the density of the upper layer is much smaller than that of the lower layer.

关键词： two-layer fluid free surface random interracial waves second-order solutions

AN ADAPTIVE NONMONOTONIC TRUST REGION METHOD WITH CURVILINEAR SEARCHES

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Journal of Computational Mathematics 2006年第6期24卷 761-770页

作者： qun-yan Zhou Wen-yu sun School of Mathematics and Computer Science Nanjing Normal University Nanjing 210097 China Department of Mathematics Jiangsu Teacher University of Technology Changzhou 213001 China

In this paper, an algorithm for unconstrained optimization that employs both trust region techniques and curvilinear searches is proposed. At every iteration, we solve the trust region subproblem whose radius is generated adaptively only once. Nonmonotonic backtracking curvilinear searches are performed when the solution of the subproblem is unacceptable. The global convergence and fast local convergence rate of the proposed algorithms are established under some reasonable conditions. The results of numerical ＇experiments are reported to show the effectiveness of the proposed algorithms.

关键词： Unconstrained optimization Preconditioned gradient path Trust region method,Curvilinear search.

A NONMONOTONE SECOND-ORDER STEPLENGTH METHOD FOR UNCONSTRAINED MINIMIZATION

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Journal of Computational Mathematics 2007年第1期25卷 104-112页

作者： qun-yan Zhou Wen-yu sun Department of Basic Science Jiangsu Teachers University of Technology Changzhou 213001 China School of Mathematics and Computer Science Nanjing Normal University Nanjin9 210097 China School of Mathematics and Computer Science Nanjing Normal University Nanjing 210097 China

In this paper, a nonmonotone method based on McCormick＇s second-order Armijo＇s step-size rule [7] for unconstrained optimization problems is proposed. Every limit point of the sequence generated by using this procedure is proved to be a stationary point with the second-order optimality conditions. Numerical tests on a set of standard test problems are presented and show that the new algorithm is efficient and robust.

关键词： Nonmonotone method Armijo's line search Direction of negative curvature,Unconstrained optimization.

Analytically Derived Wind Wave Growth Relations

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China Ocean Engineering 2002年第3期17卷 359-368页

作者： GUAN Changlong(管长龙) sun qun(孙群) Physical Oceanography Laboratory and Institute of Physical Oceanography Ocean University of Qingdao Qingdao 266003 China Physical Oceanography Laboratory and Institute of Physical Oceanography Ocean University of Qingdao Qingdao 266003 China

By the use of the 3/2 power law presented by Toba combined with the significant wave energy balance equation for wind wave, wind wave growth at a limited fetch is analytically investigated. The new wind wave growth relations (WWGRs) are analytically derived with sheltering coefficient and wind drag coefficient as parameters. The geometrical average of observational values of sheltering coefficient and the arithmetic average of observational values of wind drag coefficient are applied to determine the new WWGRs. Comparisons with existing empirical WWGRs are made.

关键词： wind wave wind wave growth relation 3/2 power law

Normal Bases and Their Dual-Bases over Finite Fields

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Acta Mathematica Sinica,English Series 2006年第3期22卷 845-848页

作者： qun Ying LIAO Qi sun The Mathematical College of Sichuan University The Mathematical and Soft-Ware Scientific College of Sichuan Normal University

In this paper, we prove the following results： 1） A normal basis N over a finite field is equivalent to its dual basis if and only if the multiplication table of N is symmetric; 2） The normal basis N is self-dual if and only if its multiplication table is symmetric and Tr（α^2） = 1, where α generates N; 3） An optimal normal basis N is self-dual if and only if N is a type-Ⅰ optimal normal basis with q = n = 2 or N is a type-Ⅱ optimal normal basis.

关键词： Normal bases over finite fields Optimal normal bases Multiplication tables of normal bases

Effect of Stokes drift on upper ocean mixing

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Acta Oceanologica Sinica 2008年第2期27卷 11-20页

作者： LI Shuang SONG Jinbao sun qun Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Graduate School Chinese Academy of Sciences Beijing 100039 China

Stokes drift is the main source of vertical vorticity in the ocean mixed layer. In the ways of Coriolis - Stokes forcing and Langmuir circulations, Stokes drift can substantially affect the whole mixed layer. A modified Mellor-Yamada 2. 5 level turbulence closure model is used to parameterize its effect on upper ocean mixing conventionally. Results show that comparing surface heating with wave breaking, Stokes drift plays the most important role in the entire ocean mixed layer, especially in the subsurface layer. As expected, Stokes drift elevates both the dissipation rate and the turbulence energy in the upper ocean mixing. Also, ilffluence of the surface heating, wave breaking and wind speed on Stokes drift is investigated respectively. Research shows that it is significant and important to assessing the Stokes drift into ocean mixed layer studying. The laboratory observations are supporting numerical experiments quantitatively.

关键词： Stokes drift Langmuir circulations Coriolis - Stokes forcing upper ocean mixing Mellor-Yamada 2. 5 turbulence model wave breaking surface heating

金属掺杂的磷烯对亚甲基蓝的吸附机理:DFT-D研究

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原子与分子物理学报 2025年第3期42卷 52-60页

作者：王群周乃武赵虹林杨丽欣邓壹铭单正莉杨志豪邓良平梅青刚孙玉希绵阳师范学院生态安全与保护四川省重点实验室绵阳621006 绵阳师范学院生命科学与技术学院绵阳621006 绵阳师范学院化学与化学工程学院绵阳621000 绵阳师范学院光致功能材料重点实验室绵阳621006 曲阜师范大学生命有机分析重点实验室山东曲阜273165 北京市食品风味化学重点实验室北京100048

随着工业的发展,染料废水对人类和环境的危害愈加显著,其中偶氮类的亚甲基蓝这种染料废水不仅色度大,而且难以降解.因此设计一种高效且灵敏的吸附剂来去除亚甲基蓝对人类和环境的危害是亟须解决的问题.本研究利用基于色散力校正的密度... 详细信息

随着工业的发展,染料废水对人类和环境的危害愈加显著,其中偶氮类的亚甲基蓝这种染料废水不仅色度大,而且难以降解.因此设计一种高效且灵敏的吸附剂来去除亚甲基蓝对人类和环境的危害是亟须解决的问题.本研究利用基于色散力校正的密度泛函理论(DFT-D)的第一性原理方法探索了本征及掺杂磷烯吸附剂对亚甲基蓝的吸附机理,并详细考察了本征及掺杂Al,Ca,Ti和Fe金属原子后的磷烯对亚甲基蓝吸附的影响.研究结果表明亚甲基蓝初始构型会影响磷烯对其吸附,当亚甲基蓝平躺于磷烯表面时有较大的吸附,且金属原子掺杂显著地影响其对亚甲基蓝的吸附能力,掺杂金属原子均增大了磷烯对亚甲基蓝的吸附.其中吸附能力是Fe掺杂磷烯>Ca掺杂磷烯>Ti掺杂磷烯>Al掺杂磷烯.研究结论对于亚甲基蓝的处理带来了新的指导方向,有望为相关染料废水的检测和去除提供有意义的理论参考.

关键词：亚甲基蓝色散力校正密度泛函理论磷烯掺杂磷烯

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Tribological behavior of AISI302 austenitic stainless steel modified by elevated temperature nitrogen plasma immersion ion implantation

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中国有色金属学会会刊：英文版 2004年第z1期14卷 301-304页

作者： JIANG Shao-qun MA Xin-xin sun Yue School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

AISI302 stainless steel samples were modified by elevated temperature nitrogen plasma immersion ion implantation at temperature ranging from 330 ℃ to 450 ℃. The tribological behaviors of the implanted layers of the samples were investigated. The samples were characterized by Auger electron spectroscopy (AES), glancing angle X-ray diffraction (GXRD), and nanoindentation. The results show that the implantation temperature plays an important rule on the microstructure and surface properties of the implanted layers. The thickness of the modified layer implanted at 390 ℃ is about 9 μm. It is improved about two orders compared with that of the implanted at room temperature. The surface nanohardness and the wear resistance of elevated temperature implanted layers increase significantly, and the friction coefficient decreases obviously in comparison with the unimplanted one. These data suggests that the improvement results from the formation of new phases such as ε-(Fe, Cr, Ni)2+xN, or noncrystal phase.

关键词： austenite stainless steel elevated temperature plasma immersion ion implantation tribology nanohardness