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Journal of Environmental Sciences 2020年第9期32卷 82-90页

作者： Jianqiang Zhu Jianlong Li lin du Environment Research Institute Shandong UniversityQingdao 266237China

Secondary organic aerosol(SOA)formation potential for six kinds of short aliphatic ethers has been *** size distribution,mass concentration,and yield of SOA formed by ethers photooxidation were determined under different *** results showed that all six ethers can generate SOA via reaction with OH radicals even under no seed and NOxfree *** mass concentration for six seedless experiments was less than 10μg/m3 and the SOA yields were all below 1%.The strong increase in the SOA formation was observed when the system contained ammonium sulfate seed particles,while SOA yield decreased under the high-NOx *** composition was analyzed using offline *** spectra indicated that there are complex components in the particle-phase including carbonyls acid and aldehydes ***,the aqueous filter extracts were analyzed using ultraviolet-visible spectrometer and fluorescence *** the fresh methyl n-butyl ether SOA,the largest absorption peak occurs at 280 nm and there exists slightly absorption in the 300-400 ***-emission matrices display the distinct peak at excitation/emission=470 nm/480 nm according to the fluorescence *** findings are important considerations of formation for ether SOA that can eventually be included in atmospheric models.

关键词： aerosol photooxidation potential

Photoelectron Spectroscopy, Photoionization Mass Spectroscopy, and Theoretical Study on CCl3SSCN

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Chinese Journal of Chemical Physics 2008年第2期21卷 93-98页

作者： lin du Li Yao Mao-fa Ge Beijing National Laboratory for Molecular Sciences State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

Trichloromethanesulfenyl thiocyanate, CCl3SSCN, was generated and studied by photoelectron spectroscopy （PES）, photoionization mass spectroscopy （PIMS）, and theoretical calculations. This molecule exhibits a gauche conformation, and the torsional angle around S-S bond is 91.4° due to the sulfur-sulfur lone pair interactions. After ionization, the ground-state cationic-radical form of CCl3SSCN＋ adopts a trans planar main-atom structure with Cs symmetry. The highest occupied molecular orbital （HOMO） of CC13SSCN corresponds to the electrons mainly localized on the sulfur 3p lone pair MO. The first ionization energy is determined to be 10.40 cV.

关键词： Photoelectron spectroscopy Photoionization mass spectroscopy Electronic structure

Synchronization in a fractional-order dynamic network with uncertain parameters using an adaptive control strategy

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Applied Mathematics and Mechanics(English Edition) 2018年第3期39卷 353-364页

作者： lin du Yong YANG Youming LEI Department of Applied Mathematics Northwestern Polytechnical University

This paper studies synchronization of all nodes in a fractional-order complex dynamic network. An adaptive control strategy for synchronizing a dynamic network is proposed. Based on the Lyapunov stability theory, this paper shows that tracking errors of all nodes in a fractional-order complex network converge to zero. This simple yet prac- tical scheme can be used in many networks such as small-world networks and scale-free networks. Unlike the existing methods which assume the coupling configuration among the nodes of the network with diffusivity, symmetry, balance, or irreducibility, in this case, these assumptions are unnecessary, and the proposed adaptive strategy is more feasible. Two examples are presented to illustrate effectiveness of the proposed method.

关键词： fractional-order chaotic system synchronization complex dynamic net-work adaptive control

Erosion corrosion of low-alloy wear-resistant steels in alkaline slurry

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Journal of Iron and Steel Research International 2017年第10期24卷 1065-1072页

作者： Feng-ming Song lin-xiu du State Key Laboratory of Rolling Technology and Automation Northeastern UniversityShenyang 110004LiaoningChina

Erosion corrosion causes significant problems in various industrial environments through a synergistic effect which results in much greater weight loss than the sum of the weight losses in the individual *** erosion-corrosion behavior of three low-alloy steels was investigated in a simulated concrete slurry using the rotation *** key influencing factors and mechanism of material degradation were *** experimental results indicate that the weight loss increases with the linear velocity according to a nearly exponential relationship（W =KV^n）,where nis *** weight loss is mainly caused by erosion in the alkaline slurry,and steels with higher tensile strengths show higher erosion-corrosion *** formation of many platelets and ring cracks and their removal from the sample surface during erosion corrosion in the slurry are thought to constitute the mechanism responsible for this weight *** platelets and ring cracks are formed by solid particles striking the sample *** are initially produced and subsequently disappear as they grow and come in contact with each *** craters were observed on the surfaces of samples that exhibited higher weight *** surface of the material became work-hardened because of the effect of the particles striking and scratching,and a deformed layer was produced on the surface for steels of lower strengths,leading to deeper and more abundant gouges.

关键词： Erosion Corrosion Slurry Synergy Steel

Numerical Investigation of an Oscillating Airfoil using Immersed Boundary Method

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Journal of Thermal Science 2011年第5期20卷 413-422页

作者： Guohua Zhong lin du Xiaofeng Sun Aviation China Engineering General Electric Co. Shanghai 201203 China School of Jet Propulsion Beihang University B eijing 100191 China

Based on the immersed boundary method, a numerical simulation for an oscillating airfoil is established and a preliminary analysis of the oscillating airfoil is presented with an emphasis on the physical understanding of fluid-structure interaction. In order to validate the method, two simulation cases： oscillating circular cylinder at low K-C number and two degrees of freedom oscillating cylinder are carded out first and the results are in good agreement with the previous re：searches. In the oscillating airfoil simulation, it is found that the reduced velocity U^＊. is a very sensitive factor and especially U^＊-2.8 is the critical stable boundary in the present work. The method shows the predominance of time saving in computational process for such a complicated fluid-structure interac- tion problem.

关键词： turbomachinery IB method fluid-structure interaction.

Environmental chamber study of the photochemical reaction of ethyl methyl sulfide and NO_x

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Journal of Environmental Sciences 2009年第2期21卷 137-141页

作者： WANG Kun du lin GE Maofa State Key Laboratory for Structural Chemistry of Unstable and Stable Species Beijing National Laboratory for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China Graduate University of the Chinese Academy of Sciences Beijing 100039 China

A series of experiments were conducted in a self-made smog chamber at （300 ＋ 1） K and 1.01 × 10^5 Pa to simulate the photochemical reaction of ethyl methyl sulfide （EMS） and NOx. The results showed that the higher the initial concentration of EMS, the more ozone was generated in the simulative reactions. It was found that the light intensity plays a very important role in the evaluation of ozone formation potential for EMS. The parameters of d（Oa-NO） and IR （incremental reactivity） were used to quantify the potential of EMS on ozone formation. The obtained maximum IR values in this article for the five simulative reactions were 1.55 × 10^-2, 0.99 × 10^-2, 1.36 × 10^-2, 2.47 × 10^-2, and 1.65 × 10^-2, respectively. A comparison between the results we obtained here and the results we obtained previously for di-tert-butyl peroxide and acetylene showed that the potential reactivity of EMS on ozone formation was at a relatively low level.

关键词： smog chamber photochemical reaction ethyl methyl sulfide incremental reactivity

Picoliter droplet array based on bioinspired microholes for in situ single-cell analysis

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Microsystems & Nanoengineering 2020年第1期6卷 951-959页

作者： lin du Huan Liu Jia Zhou State Key Laboratory of ASIC and System School of MicroelectronicsAcademy for Engineering&TechnologyFudan UniversityShanghai 200433China Tian Jin Tuo Rui Med Technology Co. LtdTianjin 200438China

The division of aqueous samples into microdroplet arrays has many applications in biochemical and medical *** by biological features,we propose a method to produce picoliter droplet arrays for single-cell analysis based on physical structure and interface.A 0.9 pL droplet array with an RSD(relative standard deviation)less than 6.3%and a density of 49,000 droplets/cm^(2) was successfully generated on a PDMS chip(polydimethylsiloxane)from a micromachined glass *** droplet generation principle of the wetting behavior in the microholes with splayed sidewalls on the PDMS chip by liquid smearing was *** feasibility of the picoliter droplets for bacterial single-cell analysis was verified by the separation of mixed bacteria into single droplets and isolated in situ bacteria propagation.

关键词： analysis analysis PDMS

Partition of GB-InSAR deformation map based on dynamic time warping and k-means

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Journal of Systems Engineering and Electronics 2022年第4期33卷 907-915页

作者： TIAN Weiming du lin DENG Yunkai DONG Xichao Radar Research Lab School of Information and ElectronicsBeijing Institute of TechnologyBeijing 100081China Key Laboratory of Electronic and Information Technology in Satellite Navigation(Beijing Institute of Technology) Ministry of EducationBeijing 100081China School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Centre Chongqing 401120China Advanced Technology Research Institute Beijing Institute of TechnologyJi'nan 250300China

Ground-based interferometric synthetic aperture radar(GB-InSAR)can take deformation measurement with a high *** of the GB-InSAR deformation map benefits analyzing the deformation state of the monitoring scene *** partition methods rely on labelled datasets or single deformation feature,and they cannot be effectively utilized in GBInSAR *** paper proposes an improved partition method of the GB-InSAR deformation map based on dynamic time warping(DTW)and *** DTW similarities between a reference point and all the measurement points are calculated based on their time-series *** the DTW similarity and cumulative deformation are taken as two partition *** the k-means algorithm and the score based on multi evaluation indexes,a deformation map can be partitioned into an appropriate number of *** datasets of West Copper Mine are processed to validate the effectiveness of the proposed method,whose measurement points are divided into seven classes with a score of 0.3151.

关键词： ground-based interferometric synthetic aperture radar(GB-InSAR) deformation map partition dynamic time warping(DTW) k-means

Research on data assimilation strategy of turbulent separated flow over airfoil

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Applied Mathematics and Mechanics(English Edition) 2022年第4期43卷 571-586页

作者： Ying ZHANG lin du Weiwei ZHANG Zichen DENG National Key Laboratory of Science and Technology on Aerodynamic Design and Research School of AeronauticsNorthwestern Polytechnical UniversityXi'an 710072China Complex System Dynamics and Control Academic Exchange Center School of Mathematics and StatisticsNorthwestern Polytechnical UniversityXi'an 710119China Rotor Aerodynamics Key Laboratory China Aerodynamics Research and Development CenterMianyang 621000Sichuan ProvinceChina

In order to increase the accuracy of turbulence field reconstruction,this paper combines experimental observation and numerical simulation to develop and establish a data assimilation framework,and apply it to the study of S809 low-speed and high-angle airfoil *** method is based on the ensemble transform Kalman filter(ETKF)algorithm,which improves the disturbance strategy of the ensemble members and enhances the richness of the initial members by screening high flow field sensitivity constants,increasing the constant disturbance dimensions and designing a fine disturbance *** results show that the pressure distribution on the airfoil surface after assimilation is closer to the experimental value than that of the standard Spalart-Allmaras(S-A)*** separated vortex estimated by filtering is fuller,and the eddy viscosity field information is more abundant,which is physically consistent with the observation ***,the data assimilation method based on the improved ensemble strategy can more accurately and effectively describe complex turbulence phenomena.

关键词： turbulence data assimilation ensemble disturbance strategy large angle of attack separation ensemble transform Kalman filter(ETKF)

Dynamic dam-reservoir interaction analysis including effect of reservoir boundary absorption

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Science China(Technological Sciences) 2007年第z1期50卷 1-10页

作者： lin Gao du JianGuo HU ZhiQiang School of Civil and Hydraulic Engineering Dalian University of TechnologyDalian 116024China School of Civil and Hydraulic EngineeringDalian University of TechnologyDalian 116024China School of Civil and Hydraulic EngineeringDalian University of TechnologyDalian 116024China

Based on the scaled boundary finite-element method, the governing equations for the analysis of dam-reservoir interaction including the reservoir boundary absorption are developed. Coupling with the equation of dam-unbounded foundation interaction, it can effectively carry out the earthquake response analysis of dameservoir-foundation system. The proposed approach has the advantages that the effect of compressibility of reservoir water as well as the energy absorption of reservoir boundary on the earthquake response of arch dams and gravity dams can be efficiently evaluated and higher accuracy can be achieved. In comparison with the methods available in the literature, the computational cost can be reduced to a great extent. It facilitates the application of earthquake response analysis of dam-reservoir-foundation system including reservoir boundary absorption to the engineering practice.

关键词： scaled boundary finite-element method dam-reservoir interaction reservoir boundary absorption