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Study on the passive film formed on 2205 stainless steel in acetic acid by AAS and XPS

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International Journal of Minerals,Metallurgy and Materials 2009年第2期16卷 170-176页

作者： Xue-qun Cheng Xiao-gang Li Chao-fang dong Corrosion and Protection Center University of Science and Technology Beijing Beijing 100083 China

The properties of the passive film formed on 2205 stainless steel in acetic acid at high temperature that contained chloride ions were studied by atomic absorption spectrometry （AAS）, X-ray photoelectron spectroscopy （XPS）, and electrochemical polarization measurements. AAS results show that molybdenum is enriched on the surface as the passive film is dissolved. This enrichment decreases the corrosion resistance because it hinders chloride adsorption and Fe ion dissolution, and acts as a local pH buffer because it consumes protons. The dissolution ratio of Fe/Cr is approximately 10 during the active dissolution of the passive film. XPS results indicate that when the potential is in the passivation region, Cr comprises about 50% of the metal cations in the near-surface region of the passive film and is the main metal constituent in this region. When the polarization potential is much greater than the transpassivation potential, the Mo content accounts for approximately 45% of the metal cations in the nearurface region; Fe and Ni have no obvious influence on the formation, dissolution, or puncture of the passive film.

关键词： acetic acid corrosion electrochemical behavior stainless steel passive film

Impact of Atmospheric Transmittance and NLTE Correction on Simulation of High Spectral Infrared Atmospheric Sounder onboard FY-3E

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Journal of Meteorological Research 2024年第2期38卷 225-234页

作者： Chenggege fang Peiming dong Yang HAN Wanlin KAN Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological AdministrationNanjing University of Information Science&TechnologyNanjing 210044 donghai Laboratory Zhoushan 316021 State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081 CMA Earth System Modeling and Prediction Centre China Meteorological Administration(CMA)Beijing 100081 Key Laboratory of Transportation Meteorology of China Meteorological Administration Nanjing Joint Institute for Atmospheric SciencesNanjing 210041

With the launch of the first civilian early-morning orbit satellite Fengyun-3E(FY-3E),higher demands are placed on the accuracy of radiative transfer simulations for hyperspectral infrared ***,several key issues are investigated in the ***,the accuracy of the fast atmospheric transmittance model implemented in the Advanced Research and Modeling System(ARMS)has been evaluated with both the line-by-line radiative transfer model(LBLRTM)and the actual satellite *** results indicate that the biases are generally less than 0.25 K when compared to the LBLRTM,while below 1.0 K for the majority of the channels when compared to the ***,during both comparisons,significant biases are observed in certain *** accuracy of Hyperspectral Infrared Atmospheric Sounder-II(HIRAS-II)onboard FY-3E is comparable to,and even superior to that of the Cross-track Infrared Sounder(CrIS)onboard ***,apodization is a crucial step in the processing of hyperspectral data in that the apodization function is utilized as the instrument channel spectral response function to produce the satellite channel-averaged *** further explore the difference between the apodized and unapodized simulations,Sinc function is adopted in the fast transmittance *** is found that the use of Sinc function can make the simulations fit the original satellite observations *** simulating with apodized observations,the use of Sinc function exhibits larger deviations compared to the Hamming ***,a correction module is applied to minimize the impact of Non-Local Thermodynamic Equilibrium(NLTE)in the shortwave infrared *** is verified that the implementation of the NLTE correction model leads to a significant reduction in the bias between the simulation and observation for this band.

关键词： high spectral infrared sounding atmospheric transmittance apodization Non-Local Thermodynamic Equilibrium Fengyun-3E(FY-3E)

Integrating 16S sequencing and metabolomics study on anti-rheumatic mechanisms against collagen-induced arthritis of Wantong Jingu Tablet

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Chinese Journal of Natural Medicines 2022年第2期20卷 120-132页

作者： LI Zhao-dong QI fang-Yuan LI Fan Department of Pathogenobiology the Key Laboratory of ZoonosisMinistry of Education of ChinaSchool of Basic MedicineJilin UniversityChangchun 130000China Key Laboratory for Bionics Engineering Ministry of Education of ChinaJilin UniversityChangchun 130000China Engineering Research Center for Medical Biomaterials of Jilin Province Jilin UniversityChangchun 130000China Key Laboratory for Biomedical Materials of Jilin Province Jilin UniversityChangchun 130000China State Key Laboratory of Pathogenesis Prevention and Treatment of High Incidence Diseases in Central AsiaUrumqi 830000China

Wantong Jingu Tablet(WJT),a mixture of traditional Chinese medicine,was reported to relieve the symptoms of rheumatoid arthritis(RA),but its pharmacological mechanism was not completely *** aim of this study was to investigate the therapeutic mechanisms of WJT for RA in *** effects of WJT on joint pathology,as well as the levels of Bax,Bcl-2,caspase-3,cleaved-caspase-3,ERK1/2,pERK1/2,TNF-α,IL-1β,and IL-6 were measured using collagen-induced arthritis(CIA)*** intestinal flora composition and the metabolites alteration were analyzed by 16S rDNA sequencing and metabolomics method,*** found that WJT ameliorated the severity of the CIA rats which might be mediated by inducing apoptosis,inactivating the MEK/ERK signals and reducing the production of pro-inflammatory ***,in part,relieved the gut microbiota dysbiosis,especially bacterial phylum Bacteroidetes,Tenericutes and Deferribacteres,as well as bacterial genus Vibrio,Macrococcus and Vagococcus.3’-N-debenzoyl-2’-deoxytaxol,tubulysin B,and magnoline were significantly associated with the specific *** identified serotonin,glutathione disulfide,N-acetylneuraminic acid,naphthalene and thromboxane B2 as targeted molecules via *** findings contributed to the understanding of RA pathogenesis,and WJT played essential roles in gut microbiota health and metabolite modulation in the CIA rats.

关键词： Rheumatoid arthritis 16S rDNA sequencing Metabolomics Pathogenesis Wantong Jingu Tablet

Multiple-stage spatial-temporal cooperative guidance without time-to-go estimation

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Chinese Journal of Aeronautics 2024年第9期37卷 399-416页

作者： Chunyan WANG Weilin WANG Wei dong Jianan WANG fang DENG School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China National Key Lab of Autonomous Intelligent Unmanned Systems Beiing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China

This paper investigates the spatial-temporal cooperative guidance problem for multiple flight vehicles without relying on time-to-go ***,a two-stage cooperative guidance strategy,namely the cooperative guidance and the Proportional Navigation Guidance(PNG)stage strategy,is developed to realize the spatial-temporal constraints in two *** the former stage,two controllers are designed and superimposed to satisfy both impact time consensus and impact angle *** the convergent conditions are satisfied,the flight vehicles will switch to the PNG stage to ensure zero miss *** further extend the results to three dimensions,a planar pursuit guidance stage is additionally imposed at the beginning of *** to the inde-pendence of time-to-go estimation,the proposed guidance strategy possesses great performance in satisfying complex spatial-temporal constraints even under flight speed ***,several numerical simulations are implemented to verify the effectiveness and advantages of the proposed results under different scenarios.

关键词： Cooperative guidance Guided missiles Impact time consensus Impact angle constraint Spatial-temporal cooperative guidance

Fundamental diagrams for pedestrian flows in a channel via an extended social force model

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Journal of Hydrodynamics 2018年第5期30卷 950-957页

作者： Yan-fang Wei dong-kai Lan Li-yun dong Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China College of Physical Science and Technology Yulin Normal University Yulin 537000 China Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai 200072 China

In this paper, an extended social force model was applied to investigate fundamental diagrams of pedestrian flows. In the presented model, both the static floor field and the view field were taken into account. Then each pedestrian can determine his/her desired walking directions according to both global and local information. The fundamental diagrams were obtained numerically under periodic boundary condition. It was found that the fundamental diagrams show good agreement with the measured data in the case of unidirectional flow, especially in the medium density range. However, the fundamental diagram for the case of bidirectional flow gave larger values than the measured data. Furthermore, the bidirectional flux is larger than the tmidirectional flux in a certain density range. It is indicated that the bidirectional flow may be more efficient than the unidirectional flow in some cases. The process of lane formation is quite quick in the model. Typical flow patterns in three scenarios were given to show some realistic applications.

关键词： Pedestrian flow social force model view field floor field fundamental diagram

Research on disruptive design pre-identification in the preliminary design phase of aero engine flow pass multidisciplinary optimization

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Chinese Journal of Aeronautics 2022年第11期35卷 264-276页

作者： Shaojing dong Yufan fang Wentong HU Xiuli SHEN Gaoxiang CHEN School of Energyand Power Engineering Beihang UniversityBeijing 10083China Beijing Key Laboratory of Aero-Engine Structure and Strength Beihang UniversityBejing 100083China Jiangxi Research Institute Beihang UniversityNanchang 330096China Navigation and Control Technology Research Institute of China Ordnance Industries Beijing 100089China Research Institute of Aero-engine Beihang UniversityBeijing 100083China

In aero engine design, determining whether the preliminary design will have disruptive effects on the detailed design is the key to multidisciplinary design optimization in the preliminary design stage. In order to adapt to the non-orthogonal parameter value range caused by the selfconstrained parametric modeling method, a non-orthogonal space mapping method that maps the optimal Latin hypercube sampling points of the traditional orthogonal design space to the non-orthogonal design space is proposed. Based on the logical regression method in machine learning field, a kind of feasible domain boundary identification method is employed to identify whether the sample spatial response meets the relevant criteria. The method proposed in this paper is used to identify and analyze the key technologies of the high-pressure turbine mortise joint structure. It is found that the preliminary design of the aero engine may lead to the failure to obtain a mortise joint structure meeting the design requirements in the detailed design stage. The mortise joint structure needs to be pre-optimized in the preliminary design stage.

关键词： Aero engine Disruptive design Flow pass multidisciplinary optimization Pre-identification Preliminary design phase

Size-dependent vibration and buckling of porous functionally graded microplates based on modified couple stress theory in thermal environments by considering a dual power-law distribution of scale effects

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Applied Mathematics and Mechanics(English Edition) 2024年第12期45卷 2075-2092页

作者： Feixiang TANG Shaonan SHI Siyu HE fang dong Sheng LIU Key Laboratory of Transients in Hydraulic Machinery Ministry of Education School of Power and Mechanical Engineering Wuhan University China-EU Institute for Clean and Renewable Energy Huazhong University of Science &Technology The Institute of Technological Sciences Wuhan University

In this study, the thermodynamic behaviors of the intrinsic frequency and buckling temperature of rectangular plates of functionally graded materials(FGMs) are explored based on the modified couple stress theory(MCST) and the novel dual powerlaw scale distribution theory. The effects of linear, homogeneous, and non-homogeneous temperature fields on the frequency and buckling temperature of FGM microplates are evaluated in detail. The results show that the porosity greatly affects the mechanical properties of FGM plates, reducing their frequency and flexural temperature compared with non-porous plates. Different temperature profiles alter plate frequencies and buckling temperatures. The presence and pattern of scale effect parameters are also shown to be crucial for the mechanical response of FGM plates. The present research aims to provide precise guidelines for the micro-electro-mechanical system(MEMS) fabrication by elucidating the complex interplay between thermal, material, and structural factors that affect the performance of FGM plates in advanced applications.

关键词： 74H45 dual power law functionally graded material (FGM) O341 pore distribution scale distribution scale effect thermal buckling thermal vibration

The pathway toward practical application of lithium-metal anodes for non-aqueous secondary batteries

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National Science Review 2022年第8期9卷 194-210页

作者： Panlong Li Zhong fang Xiaoli dong Congxiao Wang Yongyao Xia Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Institute of New Energy iChEM (Collaborative Innovation Center of Chemistry for Energy Materials) Fudan University

The revolution of automotive vehicles(from petrol vehicles to electric vehicles) has set high demands for the performance of batteries. Lithium-metal batteries(LMBs) show great potential owing to their high energy density but encounter poor cycle life and safety issues. It is of great significance to reveal LMB failure mechanisms and understand their relationship with battery performance. This review presents an overview of the state-of-the-art Li-metal anodes, with an emphasis on two typical failure modes: capacity degradation and dendritic growth of Li metal. The critical correlations between the composition, structure and failure are explained point by point. The chemical and electrochemical stabilities of the lithium anode are ***, for the first time, five types of lithium-metal anodes are classified to develop a comprehensive understanding of LMBs. Furthermore, strategies are suggested to improve the practical performance of LMBs, including material innovation, electrolyte modification and advanced characterization.

关键词： lithium-metal anode failure mode concentration polarization dead Li

Achieving ultrahigh electrocatalytic NH_(3) yield rate on Fe-doped Bi_(2)WO_(6) electrocatalyst

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Nano Research 2021年第8期14卷 2711-2716页

作者： Yongqin Liu Liang Huang Youxing fang Xinyang Zhu Shaojun dong College of Chemistry Jilin UniversityChangchun 130012China State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of ScienceChangchun 130022China

NH_(3),derived from electrocatalytic nitrogen reduction reaction(NRR),is promising to satisfy the need of food production and serve as a carbon-free liquid energy carrier in the near *** major challenges remain in enhancing NH_(3) yield rate and conversion efficiency of available *** work achieved an ultrahigh electrocatalytic NH_(3)yield rate on the_(0.50)Fe-Bi_(2)W0_(6) catalyst by a facile Fe-doped *** to 289μg·h^(-1)·mg_(cat)^(-1) of NH_(3) formation rate was obtained at-0.75 V ***,which was reliably quantized by indophenol blue and ^(1)H NMR *** impressive result is an order of magnitude higher than that of the reported Fe-and Bi-based catalysts,even more superior than the result of single atom Ru *** key of the outstanding NRR behaviors on the_(0.50)Fe-Bi_(2)W0_(6) catalyst is the significant hydrogen evolution reaction(HER)suppression and the synergy between Bi and Fe,which can effectively modulate the electron distribution and accelerate the electron *** work endows a new insight to further explore the high-performance electrocatalysts toward NRR.

关键词： electrocatalytic ammonia synthesis ultrahigh NH_(3)yield rate Fe-doped Bi_(2)WO_(6) synergy effect suppressing HER