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Structure and photochromic properties of molybdenumphosphoric acid/TiO_2 composite films

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Science China Chemistry 2009年第2期52卷 169-173页

作者： QI He,LIU Yan,FENG Wei & ZHU YiMin College of Environmental Science and Engineering,dalian Maritime University,dalian 116026,China College of Environmental Science and Engineering Dalian Maritime University Dalian China

TiO_2 sol-gel composite films with dropping molybdenumphosphoric acid(PMoA) have been prepared by sol-gel *** structure and constitute of composite thin films were studied with Fourier transforms infrared spectroscopy(FT-IR),atomic force microscopy(AFM),and X-ray diffraction(XRD) patterns,*** photochromic behavior and mechanism of composite thin films were inves-tigated with ultraviolet-visible spectra(UV-vis) and electron spin resonance(ESR).FT-IR results showed that the Keggin geometry of PMoA was still preserved inside PMoA/TiO2 composite thin films,and a charge transfer bridge was built at the interface of PMoA and TiO2 through the Mo-O-Ti *** topography of the composite film showed obvious changes before/after adding PMoA,and the surface topography of composite films showed obvious changes before/after irradiating as *** thin film had reversible photochromic *** with UV light,transparent films changed from colorless to blue and they can bleach completely with ambient air in the *** re-sults showed that TiO_2 were excitated by UV light to produce electrons,which deoxidized PMoA to produce *** photochromic process of PMoA/TiO_2 system was carried through elec-tron transfer mechanism.

关键词： molybdenumphosphoric acid TiO_2 composite film photochromism

Measurement and simulation of the two-phase velocity correlation in sudden-expansion gas-particle flows

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Acta Mechanica Sinica 2011年第4期27卷 494-501页

作者： Li-Xing Zhou.Yang Liu.Yi Xu Department of Engineering Mechanics,Tsinghua University,100084 Beijing,China Marine Engineering College,dalian Maritime University,116026 dalian,China Department of Engineering Mechanics Tsinghua University Beijing China Marine Engineering College Dalian Maritime University Dalian China

In this paper the present authors measured the gas-particle two-phase velocity correlation in sudden expansion gas-particle flows with a phase Doppler particle anemometer （PDPA） and simulated the system behavior by using both a Reynolds-averaged Navier-Stokes （RANS） model and a large-eddy simulation （LES）. The results of the measurements yield the axial and radial time-averaged velocities as well as the fluctuation velocities of gas and three particle-size groups （30μm, 50μm, and 95μm） and the gasparticle velocity correlation for 30μm and 50μm particles. From the measurements, theoretical analysis, and simulation, it is found that the two-phase velocity correlation of sudden-expansion flows, like that of jet flows, is less than the gas and particle Reynolds stresses. What distinguishes the two-phase velocity correlations of sudden-expansion flow from those of jet and channel flows is the absence of a clear relationship between the two-phase velocity correlation and particle size in sudden-expansion flows. The measurements, theoretical analysis, and numerical simulation all lead to the above-stated conclusions. Quantitatively, the results of the LES are better than those of the RANS model.

关键词： PDPA measurement - Simulation Two-phasevelocity correlation Sudden expansion gas-particle flows

A New Navigation Strategy in Hypermedia Integral Ware Authoring System

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计算机工程 2002年第S1期28卷 141-144页

作者： FU Xianping1 , JIANG Jianping2(1. College of Computer Science and Technology, dalian Maritime University, dalian 116026,China 2. College of Information Engineering, dalian Maritime University, dalian 116026,China ) College of Computer Science and Technology Dalian Maritime University Dalian 116026China College of Information Engineering Dalian Maritime University Dalian 116026China

After analyzing the general navigation mechanisms and discussing the knowledge point card linking model which is the base of the navigation mechanism used in the Hypermedia Integral ware Authoring System(HIAS), the pa... 详细信息

关键词： Hypermedia Integral ware Navigation strategy

DC dielectrophoresis separation of marine algae and particles in a microfluidic chip

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Science China Chemistry 2012年第4期55卷 524-530页

作者： SONG YongXin1, YANG JianDong1, SHI XiaoFei4, JIANG Hai3, WU YanBin1, PENG Ran1, WANG Qi5, GONG Ning2, PAN XinXiang1, SUN YeQing2 & LI DongQing1,31Department of Marine Engineering, dalian Maritime University, dalian 116026, China 2Institute of Environmental Systems Biology, dalian Maritime University, dalian 116026, China 3Department of Mechanical and Mechatronics Engineering, University of Waterloo, Waterloo, ON, N2L 3G1, Canada 4College of Information Science and Technology, dalian Maritime University, dalian 116026, China 5Department of Respiratory Medicine, the Second Hospital Affiliated to dalian Medical University, dalian 116026, China Department of Marine Engineering Dalian Maritime University Dalian China College of Information Science and Technology Dalian Maritime University Dalian China Department of Mechanical and Mechatronics Engineering University of Waterloo Waterloo Canada Department of Respiratory Medicine the Second Hospital Affiliated to Dalian Medical University Dalian China Institute of Environmental Systems Biology Dalian Maritime University Dalian China

This paper reports a microfluidic method of continuous separation of marine algae and particles by DC dielectrophoresis. The locally non-uniform electric field is generated by an insulating PDMS triangle hurdle fabricated within a PDMS microchannel. Both the particles and algae are subject to negative DEP forces at the hurdle where the gradient of local electric-field strength is the strongest. The DEP force acting on the particle or the algae depends on particles' or algae's volume, shape and dielectric properties. Thus the moving particles and algae will be repelled to different streamlines when passing the hurdle. In this way, combined with the electroosmotic flow, continuous separation of algae of two different sizes, and continuous separation of polystyrene particles and algae with similar volume but different shape were achieved. This first demonstration of DC DEP separation of polystyrene particles and algae with similar sizes illustrates the great influence of dielectric properties on particle separation and potentials for sample pretreatment.

关键词： DC dielectrophoresis – marine algae – particle – microfluidic chip – permittivity difference

Surface stability and conductivity of a high Cr and Ni austenitic stainless steel plates for PEMFC

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Rare Metals 2006年第Z1期25卷 229-234页

作者： TIAN Rujin SUN Juncai WANG Jianli Institute of Materials and Technology Dalian Maritime University Dalian 116026 China Institute of Materials and Technology Dalian Maritime University Dalian 116026 China Institute of Materials and Technology Dalian Maritime University Dalian 116026 China

In order to use stainless steel as bipolar plate for PEMFC, electrochemical behavior of a high Cr and Ni austenitic stainless steel was studied in the solutions containing different concentration of H2SO4 and 2 mg·L-1 F-, and interfacial contact resistance was measured after corrosion tests. The experimental results show that the passive current density lowers with decreasing the concentration of H2SO4. The interfacial contact resistance between carbon paper and passive film formed in the simulated PEMFC environment is higher than the goal of bipolar plate for PEMFC. Surface conductivity should be further reduced by surface modification.

关键词： austenitic stainless steel bipolar plate passive film interfacial contact resistance

Study on the Diffraction Patterns of α"-Fe_(16)N_2 with Jack-1 and Jack-2 Structural Parameters

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Journal of Materials Science & Technology 2000年第4期16卷 362-366页

作者： Zhiquan LIU and Douxing LI (Laboratory of Atomic Imaging of Solids, Institute of Metal Research, CAS, Shenyang 110015, China) Xiaolei XU, Liang WANG and Zukun HEI (Institute of Materials and Technology, dalian Maritime University, dalian 116026, China) Laboratory of Atomic Imaging of Solids Institute of Metal Research CAS Shenyang 110015 China Institute of Materials and Technology Dalian Maritime University Dalian 116026 China

Two body centered tetragonal (bet) crystal structures of α'-Fe_(16)N_2 with x=0.25, z=0.3125 (Jack-1) and x=0.222, z=0.306 (Jack-2) respectively, were analyzed theoretically with EMS software package. The simulation of diffraction patterns indicates that both diffraction patterns of the same axis in these two structures obey bcc extinction rule. The conclusion is also obtained from the analyses of the diffracted waves. α'-Fe_(16)N_2 precipitates in the diffusion layer of ion-nitrided α-iron have been studied with transmission electron microscope (TEM). We have distinctly observed the electron diffraction patterns of α'-Fe_(16)N_2 in [100], [111], [110], [011], [210], [021], [311], [113], [331] and [133] zone axes with perfect symmetry, which indicate the parallel orientation relationship with α matrix:α'//α'// {100}.α'// {100}ｔα. The analyses of diffraction patterns, which obey bcc extinction rule, verify the bct structure of α'-Fe_(16)N_2 discovered by X-ray diffraction.

关键词： Study on the Diffraction Patterns of Jack N2 with Jack-1 and Jack-2 Structural Parameters Fe

A New Admissibility Condition of Discrete-time Singular Systems with Time-varying Delays

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International Journal of Automation and computing 2012年第5期9卷 480-486页

作者： Yong-Yun Shao 1,3 Xiao-Dong Liu 1,2 Xin Sun 3 Zhan Su 4 1 Transportation Management College, dalian Maritime University, dalian 116026, China 2 Department of Mathematics, dalian Maritime University, dalian 116026, China 3 Department of Computer and Mathematics Teaching, Shenyang Normal University, Shenyang 110034, China 4 Institute of Systems Science, Northeastern University, Shenyang 110004, China Transportation Management College Dalian Maritime University Dalian China Department of Computer and Mathematics Teaching Shenyang Normal University Shenyang China Department of Mathematics Dalian Maritime University Dalian China Institute of Systems Science Northeastern University Shenyang China

This paper gives a novel delay-dependent admissibility condition of discrete-time singular systems with time-varying delays. For convenience, the time-varying delay is assumed to be the sum of delay lower bound and the integral multiples of a constant delay. Specially, if the constant delay is of unit length, the delay is an interval-like time-varying delay. The proposed admissibility condition is presented and expressed in terms of linear matrix inequality (LMI) by Lyapunov approach. Generally, the uncertainty of time-varying delay would lead to conservatism. In this paper, this critical issue is tackled by accurately estimating the time-varying delay. Consequently, the proposed admissibility condition is less conservative than the existing results, which is demonstrated by a numerical example.

关键词： Singular systems discrete-time delay-dependent admissibility time-varying delay

Biological exposure models for oil spill impact analysis

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Journal of Environmental Sciences 2000年第4期12卷 482-485页

作者： XIONG De qi 1, Mark Reed 2, Narve Ekrol 2 (1. Department of Marine Environmental Engineering, dalian Maritime University, dalian 116026, China E mail: deqi@*** 2. Department of Environmental Engineering, SINTEF Applied Chemistry Institut 大连海事大学辽宁大连 1 1 6 0 2 SINTEF Applied Chemistry Institute 挪威 Trondheim 70 3 4

The oil spill impact analysis (OSIA) software system has been developed to supply a tool for comprehensive, quantitative environmental impact assessments resulting from oil spills. In the system, a biological component evaluates potential effects on exposed organisms based on results from a physico chemical fates component, including the extent and characteristics of the surface slick, and dissolved and total concentrations of hydrocarbons in the water column. The component includes a particle based exposure model for migratory adult fish populations, a particle based exposure model for spawning planktonic organisms (eggs and larvae), and an exposure model for wildlife species (sea birds or marine mammals). The exposure model for migratory adult fish populations simulates the migration behaviors of fish populations migrating to or staying in their feeding areas, over wintering areas or spawning areas, and determines the acute effects (mortality) and chronic accumulation (body burdens) from the dissolved contaminant. The exposure model for spawning planktonic organisms simulates the release of eggs and larvae, also as particles, from specific spawning areas during the spawning period, and determines their potential exposure to contaminants in the water or sediment. The exposure model for wild species calculates the exposure to surface oil of wildlife (bird and marine mammal) categories inhabiting the contaminated area. Compared with the earlier models in which all kinds of organisms are assumed evenly and randomly distributed, the updated biological exposure models can more realistically estimate potential effects on marine ecological system from oil spill pollution events.

关键词： oil spill biological exposure acute effects chronic accumulation migration of fish spawning of eggs and larvae habitat

THE PHASE-OFFSET OVERLAPPED WAVE TECHNIQUE

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Journal of Electronics(China) 2003年第2期20卷 121-127页

作者： Liang Dequn (dalian Maritime University, dalian 116026)Liang Weihua (dalian University of Science and Technology, dalian 116026)Sun Changnian (Telecom Sino Group, Sunnyvale, California, USA, 94086) Dalia n Maritime University Dalian116026 dalian University of Science and Technology Dalian116026 Telecom Sino Group Sunnyvale California USA 94086

A new digital communication technology based on the Phase-Offset Overlapped Waves (POOW) has been introduced in this letter. The waves can be considered as a special multicarrier different from traditional ones. The sub-waves in a coded word's period of the POOW are sine waves and have the same frequencies, but different starting phases. The most important characteristic is that these sub-waves are the piecewise functions and not orthogonal in a code word period. The decoding can be implemented by solving a linear equation group. This code has very high efficiency and thus the data transmission rate is increased greatly.

关键词： Digital communications Coding Multicarrier Phase-offset overlapped wave