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Journal of Materials Science & Technology 2021年第30期89卷 158-166页

作者： l.l.li Z.B.Wang S.y.He y.G.Zheng CAS Key laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Department of Physics Southern University of Science and TechnologyGuangdong 518055China

The correlation between depassivation and repassivation processes,which is significant in erosioncorrosion,was quantitatively investigated by single particle impingement tests at various flow velocities and impact *** results show that both repassivation and depassivation processes are associated with the kinetic energy of solid particle,and demonstrate that the repassivation is retarded by *** phenomenon probably results from the depassivation-induced microstructure *** this basis,the dependence of critical flow velocity(CFV)for erosion-corrosion on the solid particle concentration and diameter is further theoretically predicted and experimentally ***,the crucial role of depassivation-repassivation in CFV phenomenon is further highlighted.

关键词： Erosion-corrosion Stainless steel Depassivation-repassivation Single particle impact Passive film

DESIGN　AND　PREPARATION　OF　SIlICON　NITRIDE　COMPOSITE　WITH　HIGH　FRACTURE　TOUGHNESS　AND　NACRE　STRUCTURE

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Acta Metallurgica Sinica(English letters) 1996年第6期9卷 479-484页

作者： y Huang H.N hao y.l. Chen and B.l.Zhou (1)Department of Materials Science and Engineering, Tsinghua University,Beijing 100084, China 2)Institute of Metal Research, Chinese Academy of Sciences,Shenyang 110015, China ) Tsinghua Univ Beijing China

A new way of designing and preparing silicon nitride ceramic composite with high fracture toughness and nacre structure has been proposed. To mimic the laminated structure of nacre, Si_3N_4 matrix ceramic layer can be obtained through compacting rolling method. To mimic the secondary toughening of nacre structure, SiC whisker is added into Si_3N_4 and acts as the secondary toughening phase. Boron nitride (BN)is selected to mimic the organic layer in nacre so as to form the weak interfaces between Si_3N_4 layers. Alumina is added into BN to adjust the bonding strength of the *** Si_3N_4 sheets are stacked into the die after coating with BN. After the removal of the organic matter in them, the green body is hot pressed at 1820℃for 1.5 hours under N_2 atmosphere. The fracture toughness of the so-made Si_3N_4 composite at room temperature is 20.36MPa m￣(1/2), the three-point bending strength at room temperature is 651.47MPa. The crack spreads and deflects along the interface between BN and Si_3N_4 layer and extends through the BN layer into Si_3N_4 layer. The improvement of the fracture toughness may be due to the staircase-shape-like crack which provides the long crack path, the fracture and deformation of Si_3N_4 layer, and the pullout of SiC whiskers from the Si_3N_4 layer.

关键词： secondary toughening,compact rolling silicon nitride nacre Structure

Nonlinear Transient Response of Functionally Graded Material Sandwich Doubly Curved Shallow Shell Using New Displacement Field

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Acta Mechanica Solida Sinica 2018年第1期31卷 108-126页

作者： Z.N.li y.X.hao W.Zhang J.H.Zhang College of Mechanical Engineering Beijing Information Science and Technology University College of Mechanical Engineering Beijing University of Technology

In this paper, the nonlinear transient dynamic response of functionally graded material （FGM） sandwich doubly curved shell with homogenous isotropic material core and functionally graded face sheet is analyzed using a new displacement field on the basis of Reddy＇s third-order shear theory for the first time. The equivalent material properties for the FGM face sheet are assumed to obey the rule of simple power law function in the thickness direction. Based on Reddy＇s theory of higher shear deformation, a new displacement field is developed by introducing the secant function into transverse displacement. Four coupled nonlinear differential equations are obtained by applying Hamilton＇s principle and Galerkin method. It is assumed that the FGM sandwich doubly curved shell is subjected to step loading, air-blast loading, triangular loading, and sinusoidal loading, respectively. On the basis of double-precision variable- coefficient ordinary differential equation solver, a new program code in FORTRAN software is developed to solve the nonlinear transient dynamics of the system. The influences of core thickness, volume fraction, core-to-face sheet thickness ratio, width-to-thickness ratio and blast type on the transient response of the shell are discussed in detail through numerical simulation.

关键词： New displacement fields Functionally graded materials Sandwich doubly curvedshell Blast load Nonlinear transient response

A　Conformational　Study　on　the　Interaction　of　Saporin-S6　with　Phospholipid　Vesicles

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Chemical Research in Chinese Universities 1998年第1期14卷 42-45页

作者： hao, Q Guan, ZH yan, l Zhang, y yan, Gl liu, GH Dong, QC li, QS Wang, yZ Jilin Univ Dept Mol Biol Changchun 130023 Peoples R China Jilin Univ Natl Lab Enzyme Engn Changchun 130023 Peoples R China Peoples Hosp Jilin Prov Med Testing Dept Changchun 130021 Peoples R China

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关键词： Interaction the Phospholipid Saporin-S6

large Eddy Simulation of Turbulent Channel Flows over Rough Walls with Stochastic Roughness Height Distributions

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Journal of Hydrodynamics 2020年第3期32卷 570-581页

作者： hao lu China Key laboratory of Enhanced Heat Transfer and Energy Conservation of Education Ministry School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhou 510640China

This paper studies the 3-D turbulent channel flows over rough walls with stochastic roughness height distributions by using the large eddy simulation and the immersed boundary method. The obtained mean and fluctuating velocity profiles for the smooth and rough channel flows agree well with the available numerical and experimental results. The stochastic surface roughness is found to have a more significant influence than the uniform surface roughness on the turbulent velocity statistics and the coherent structures, with the same average roughness height. With a greater variation in the roughness height, the mean velocity and the streamwise fluctuating velocity is decreased and the spanwise velocity and the wall-normal fluctuating velocity are increased. In addition, one observes larger and more profuse quasi-streamwise vortices, hairpin vortices and elongated structures above the crest plane of the roughness array in cases of highly stochastic rough walls. However, the low-speed streaky structures are broken up locally and the ejection and sweep events are depressed by the stochastic roughness below the average roughness height. The results of this study support Townsend’s wall-similarity hypothesis for both stochastic and uniform rough wall turbulences, demonstrating that in both cases the effects of the surface roughness on the turbulent flow are limited to the rough sub-layer.

关键词： large eddy simulation turbulent channel flow rough wall stochastic roughness height

Density and Seasonal Dynamics of Bemisia tabaci(Gennadius) Mediterranean on Common Crops and Weeds Around Cotton Fields in Northern China

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Journal of Integrative Agriculture 2014年第10期13卷 2211-2220页

作者： ZHANG Xiao-ming yANG Nian-wan WAN Fang-hao Gabor l lvei State Key laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural Sciences Department of Agroecology Aarhus UniversityFlakkebjerg Research Centre DK-4200 SlagelseDenmark

The density seasonal dynamics of Bemisia tabaci MED were evaluated over two years in a cotton-growing area in langfang, Hebei Province, northern China on cotton （Gossypium hirsutum l.） and six other co-occurring common plants, common ragweed （Ambrosia artemisiifolia l.）, piemarker （Abutilon theophrasti Medicus）, sunflower （Helianthus annuus l.）, sweet potato （Ipomoea batatas l.）, soybean （Glycine max l.）, and maize （Zea mays l.）. The whitefly species identity was repeatedly tested and confirmed; seasonal dynamics on the various host plants were standardized by the quartile method. B. tabaci MED appeared on weeds （the common ragweed and piemarker） about 10 days earlier than on cotton, or the other cultivated plants. The peak population densities were observed over a span of 2 to 3 weeks on cotton, starting in early （2010） or mid-August （2011）. The common ragweed growing adjacent to cotton supported the highest B. tabaci densities （no. on 100 cm2 leaf surface）, 12-22 fold higher than on cotton itself. Sunflower supported more B. tabaci than the other plants, and about 1.5-2 fold higher than cotton did, Our results indicate that weeds （esp. the common ragweed） around cotton fields could increase the population density of B. tabaci MED on cotton, while sunflower could act as a trap crop for decreasing pest pressure on cotton.

关键词： Bemisia tabaci whitefly cotton sunflower ragweed population dynamics seasonal dynamics quartile method

Decomposition solutions and B?cklund transformations of the B-type and C-type Kadomtsev–Petviashvili equations

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Communications in Theoretical Physics 2024年第6期 36-46页

作者： Xiazhi hao S y lou College of Science Zhejiang University of Technology School of Physical Science and Technology Ningbo University

This paper introduces a modified formal variable separation approach, showcasing a systematic and notably straightforward methodology for analyzing the B-type Kadomtsev–Petviashvili(BKP) equation. Through the application of this approach, we successfully ascertain decomposition solutions, B?cklund transformations, the lax pair, and the linear superposition solution associated with the aforementioned equation. Furthermore, we expand the utilization of this technique to the C-type Kadomtsev–Petviashvili(CKP) equation, leading to the derivation of decomposition solutions, B?cklund transformations, and the lax pair specific to this *** results obtained not only underscore the efficacy of the proposed approach, but also highlight its potential in offering a profound comprehension of integrable behaviors in nonlinear systems. Moreover, this approach demonstrates an efficient framework for establishing interrelations between diverse systems.

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Study on on-line failure detection method of lithium-ion battery based on Mie scattering theory

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Optoelectronics letters 2022年第8期18卷 502-507页

作者： lI Wen lü Binbin XU Minggang hao Sijia Institute of Mechanical and Electrical Engineering North China University of TechnologyBeijing 100144China

lithium-ion battery has attracted more and more attention under the background of energy crisis and environmental pollution,and safety issues have become the focus of attention.A new detection method is proposed in this paper to overcome the problems of poor versatility,low accuracy and poor sensitivity in aerosol and smoke detection in the early warning of lithium-ion battery *** is a photodetector based on Mie scattering theory,which can assist temperature,voltage and current data to realize online *** experiments have shown that a lithium-ion battery with a battery capacity of only 300 m A was overcharged under low power *** aerosol and smoke generated by the battery failure and rupture were easily detected by the detector.A small amount of aerosol and smoke could be detected under overdischarge conditions,and the feasibility of the method was fully *** results show that on-line detection of lithium-ion battery failure can be achieved under extreme conditions with few nuisance alarms,and it is characterized by low cost,high speed,high efficiency and good universality.

关键词： battery lithium smoke

Improvement of Toughness of UHMWPE/PP Blends

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Journal of Beijing Institute of Technology 2019年第3期28卷 667-674页

作者： Feixiang Guo hao Jiang Hui lü yanhua yin School of Chemistry and Chemical Engineering Beijing Institute of Technology

Ultra-high molecular weight polyethylene (UHMWPE) was blended with polypropylene (PP) in order to ensure good processing. Inorganic rigid particles were also used to toughen UHMWPE/PP blends. CaCO3 and a compound additive containing heat mixed polyethylene glycol 2000 and white diatomite were added to the blends. The crystalline, surface morphology and mechanical properties of the blends were investigated comprehensively. The toughness of the material is effectively improved. By contrast, the compound additive had a better result. When the content of additive was 15%, the elongation at the break increased by 279.2% and the fracture energy increased by 343.8% compared to the original samples.

关键词： ultra-high molecular weight polyethylene (UHMWPE) inorganic filler toughness

lyapunov-based event-triggered control for nonlinear plants subject to disturbances and transmission delays

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Science China(Information Sciences) 2020年第5期63卷 146-160页

作者： Xiaoda HU hao yU Fei hao The Seventh Research Division School of Automation Science and Electrical EngineeringBeihang University The Department of Electrical and Computer Engineering University of Alberta

This paper studies event-triggered control for disturbed nonlinear systems. A new dual-stage lyapunov-based event-triggering condition is proposed to cope with the time-varying transmission *** the first stage, the ratio of lyapunov function values at the last two triggering instants is *** based on the ratio, the corresponding threshold function is selected from two candidate forms. It is proved that the designed event-triggered control system is input-to-state practically stable with respect to the measurement errors and disturbances. Moreover, Zeno behavior is excluded successfully by calculating the lower bound of the minimum inter-event times. Finally, a simulation example is provided to show the feasibility and the effectiveness of the proposed approach.

关键词： event-triggered control nonlinear systems networked control systems disturbed systems transmission delays