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A high-order splitting scheme for the advection diffusion equation

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Journal of Environmental Sciences 2001年第4期13卷 444-448页

作者： ZHENG yong-hong shen yong-ming QIU Da-hong Guangzhou Institute of Energy Conversion the Chinese Academy of SciencesGuangzhou 510070China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116023China

A high-order splitting scheme for the advection-diffusion equation of pollutants is proposed in this paper. The multidimensional advection-diffusion equation is splitted into several one-dimensional equations that are solved by the scheme. Only three spatial grid points are needed in each direction and the scheme has fourth-order spatial accuracy. Several typically pure advection and advection-diffusion problems are simulated. Numerical results show that the accuracy of the scheme is much higher than that of the classical schemes and the scheme can he efficiently solved with little programming effort.

关键词： pollutants advecton-diffusion equation high-order scheme numerical modelling

A Group of Cu(Zr)-based BMGs with Critical Diameter in the Range of 12 to 18 mm

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Journal of Materials Science & Technology 2008年第2期24卷 149-152页

作者： yong shen Evan MA Jian XU shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Department of Materials Science and Engineering The Johns Hopkins University Baltimore Maryland 21218 USA

A group of Cu（Zr）-based bulk metallic glasses （BMGs） with critical diameter （De） in the 12 to 18 mm range have been obtained using copper mould casting. In the Cu-Zr-Y-Al quaternary system, a new record of Dc=14 mm was established for Cu-based compositions, and 16 mm for compositions based on equi-atomic CuZr. Additional partial substitution of Hf for Zr further elevated the Dc to 18 mm at Cu42Zr43Hf1.5Y3.5Al10.

关键词： Bulk metallic glasses Glass-forming ability Copper Zirconium

Strengthening mechanisms of reduced activation ferritic/martensitic steels:A review

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International Journal of Minerals,Metallurgy and Materials 2021年第3期28卷 335-348页

作者： Jin-hua Zhou yong-feng shen Nan Jia Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China The State Key Lab of Rolling&Automation Northeastern UniversityShenyang 110819China

This review summarizes the strengthening mechanisms of reduced activation ferritic/martensitic(RAFM)***-angle grain boundaries,subgrain boundaries,nano-sized M_(23)C_(6),and MX carbide precipitates effectively hinder dislocation motion and increase high-temperature strength.M23C6 carbides are easily coarsened under high temperatures,thereby weakening their ability to block *** properties are improved through the reduction of M23C6 ***,the loss of strength must be compensated by other strengthening *** review also outlines the recent progress in the development of RAFM *** dispersion-strengthened steels prevent M23C6 precipitation by reducing C content to increase creep life and introduce a high density of nano-sized oxide precipitates to offset the reduced *** plastic deformation methods can substantially refine subgrains and MX carbides in the *** thermal deformation strengthening of RAFM steels mainly relies on thermo-mechanical treatment to increase the MX carbide and subgrain *** procedure increases the creep life of TMT(thermo-mechanical treatment)9Cr-1W-0.06Ta steel by~20 times compared with those of F82H and Eurofer 97 steels under 550℃/260 MPa.

关键词： reduced activation ferritic/martensitic steel strengthening mechanism high-angle grain boundary subgrain boundary precipitate

A novel solar cell fabricated with spiral photo-electrode for capturing sunlight 3-dimensionally

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Science China(Technological Sciences) 2006年第6期49卷 663-673页

作者： LIU yong shen Hui DENG Youjun Institute for Solar Energy Systems State Key Lab of Optoelectronic Materials and Technologies Sun Yat-sen University Guangzhou 510275 China Institute for Solar Energy Systems State Key Lab of Optoelectronic Materials and Technologies Sun Yat-sen University Guangzhou 510275 China Institute for Solar Energy Systems State Key Lab of Optoelectronic Materials and Technologies Sun Yat-sen University Guangzhou 510275 China

A novel solar cell fabricated with spiral photo-electrode for capturing sunlight 3-dimensionally (3D-cell) is proposed in this paper. We studied its performance both in solar simulator and in nature sunlight. Spiral photo-electrode of 3D-cell can receive sunlight from all directions and therefore can track the sun passively. And it is much insensitive to solar azimuth angle and shade. In addition, it increases the area to obtain scattered sunlight and reflected light. Compared with the dye-sensitized solar cells using sandwich structure, it would be more advantageous in the sealing technique.

关键词： solar cell, Titania, dye-sensitized, nanocrystalline, solar to electronic conversion efficiency.

Properties of the Measurement Phase Operator in Dual-Mode Entangle Coherent States

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Chinese Physics Letters 2011年第6期28卷 122-125页

作者： HOU shen-yong YANG Kuo Department of Mathematics Yangtse River Normal UniversityChongqing 408003 Department of Physics A'ba Teachers CollegeChengdu 611741

A class of measurement phase operators of dual-mode is defined and their properties in a class of entangle coherent states are *** results indicate that the entangle coherent states display some non-classical squeezed... 详细信息

关键词： angle coherent operators

Seismic performance evaluation of steel frame-steel plate shear walls system based on the capacity spectrum method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第3期9卷 322-329页

作者： Jian-hua SHAO Qiang GU yong-kang shen College of Civil Engineering Hohai University Nanjing 210098 China Department of Civil Engineering Suzhou University of Science and Technology Suzhou 215011 China

This paper presents some methods that the standard acceleration design response spectra derived from the present China code for seismic design of buildings are transformed into the seismic demand spectra, and that the base shear force-roof displacement curve of structure is converted to the capacity spectrum of an equivalent single-degree-of-freedom （SDOF） system. The capacity spectrum method （CSM） is programmed by means of MATLABT.0 computer language. A dual lateral force resisting system of 10-story steel frame-steel plate shear walls （SPSW） is designed according to the corresponding China design codes. The base shear force-roof displacement curve of structure subjected to the monotonic increasing lateral inverse triangular load is obtained by applying the equivalent strip model to stimulate SPSW and by using the finite element analysis software SAP2000 to make Pushover analysis. The seismic performance of this dual system subjected to three different conditions, i.e. the 8-intensity frequently occurred earthquake, fortification earthquake and seldom occurred earthquake, is evaluated by CSM program. The excessive safety of steel frame-SPSW system designed according to the present China design codes is pointed out and a new design method is suggested.

关键词： Steel frame-steel plate shear walls (SPSW) system Capacity spectrum method (CSM) Seismic demand spectrum Base shear force-roof displacement Seismic performance evaluation

Polypeptide Brushes Grown via Surface-initiated Ring-opening Polymerization of α-Amino Acid N-Carboxyanhydrides

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Chinese Journal of Polymer Science 2015年第7期33卷 931-931,932-946页

作者： yong shen 李志波 Harm-Anton Klok Laboratory of Polymer Physics and Chemistry Institute of Chemistry Chinese Academy of Sciences School of Polymer Science and Engineering Qingdao University of Science and Technology cole Polytechnique Fédérale de Lausanne (EPFL) Institut des Matériaux and Institut des Sciences et Ingénierie Chimiques Laboratoire des Polymères Batiment MXD Station 12 CH-1015 Lausanne Switzerland

Polypeptide brushes are attractive platforms to generate functional and responsive interfaces that are of potential interest due to their possible biodegradability, biocompatibility and tunable secondary structures. Surface-initiated ringopening polymerization（SI-ROP） of α-amino acid N-carboxyanhydrides represents a powerful and versatile strategy to generate polypeptide brushes. This review is an attempt to capture the state-of-the-art in this field and highlights the latest developments in several selected areas. In addition to presenting an overview of the synthetic methods that have been used to generate polypeptide brushes via SI-ROP, this article will discuss the preparation of patterned polypeptide brushes, the conformational properties of surface-tethered polypeptides, ways to control chain orientation at surfaces as well as properties and applications of these thin polymer films.

关键词： Polypeptide brushes Surface α-Amino acid N-carboxyanhydrides Ring-opening polymerization Secondary structure

Synthesis of Dialkyl-substituted Terminal Olefin

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Chinese Chemical Letters 2005年第9期16卷 1213-1216页

作者： shen yong REN Bao Jian shen Qiao Xia GUO State Key Laboratory of Heavy Oil Processing The Key Laboratory of Catalysis of CNPC andFaculty of Chemical Science and Engineering China University of Petroleum Beijing 102249

Dialkyl-substituted terminal olefins were synthesized from the coupling reaction of a-olefins which were catalyzed by zirconocene dichloride/methylalumoxane （MAO） catalyst system under mild condition. High yield was gained and no other oligmer was detected. It was found that the ratio of AI/Zr is responsible for the selectivity of product.

关键词： Zirconocene dichloride methylalumoxane dialkyl-substituted terminal olefin coupling reaction

Calculation of Loudspeaker Cabinet Diffraction and Correction

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Chinese Physics Letters 2011年第10期28卷 142-145页

作者： LE Yi shen yong XIA Jie Laboratory of Modern Acoustics and Institute of Acoustics Nanjing UniversityNanjing 210093

A method of calculating the cabinet edge diffractions for loudspeaker driver when mounted in an enclosure is proposed,based on the extended Biot–Tolstoy–Medwin *** to the third order,cabinet diffractions are discussed in detail and the diffractive effects on the radiated sound field of the loudspeaker system are quantitatively described,with a correction function built to compensate for the diffractive *** method is applied to a practical loudspeaker enclosure that has rectangular *** diffractive effects of the cabinet on the forward sound radiation are investigated and predictions of the calculations show quite good agreements with experimental measurements.

关键词： mounted correction calculating