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Acta Mechanica Sinica 2011年第6期27卷 922-928页

作者： Ming-Yue Gui Bao-chun Fan gang dong State Key Laboratory of Transient Physics Nanjing University of Science and Technology 210094 Nanjing China State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology 100081 Beijing China

An oblique detonation wave for a Mach 7 inlet flow over a long enough wedge of 30 turning angle is simulated numerically using Euler equation and one-step rection *** fifth-order WENO scheme is adopted to capture the shock *** numerical results show that with the compression of the wedge wall the detonation wave front structure is divided into three sections：the ZND model-like strcuture,single-sided triple point structure and dual-headed triple point *** first structure is the smooth straight,and the second has the characteristic of the triple points propagating dowanstream only with the same velocity,while the dual-headed triple point structure is very *** detonation waves facing upstream and downstream propagate with different velocities,in which the periodic collisions of the triple points cause the oscillation of the detonation wave *** oscillation process has temporal and spatial *** addition,the triple point trace are recorded to obtain different cell structures in three sections.

关键词： Oblique detonation wave Wedge - Periodic oscillation Fine structure

Preparation and Characterization of Nano-Structured SiO_(2) Thin Films on Carbon Steel

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Chinese Chemical Letters 2003年第11期14卷 1167-1170页

作者： Rong chun XIONG dong Zhou YAN gang WEI College of Material Science and Engineering Beijing University of Chemical TechnologyBeijing 100029

Nano-structured SiO2 thin films were prepared on the surface of carbon steel for the first time by LPD. The compositions of the films were analyzed by XPS, and the surface morphology of the thin films were observed by AFM. The thin films were constituted by compact particles of SiO2, and there was no Fe in the films. In the process of film forming, the SiO2 colloid particles were deposited or absorbed directly onto the surface of carbon steel substrates that were activated by acid solution containing inhibitor, and corrosion of the substrates was avoided. The nano-structured SiO2 thin films that were prepared had excellent protective efficiency to the carbon steel.

关键词： Carbon steel sodium silicate nano-structured SiO_(2) thin films AFM.

Numerical study on three-dimensional flow field of continuously rotating detonation in a toroidal chamber

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Acta Mechanica Sinica 2012年第1期28卷 66-72页

作者： Xu-dong Zhang Bao-chun Fan Ming-Yue Gui Zhen-Hua Pan gang dong Science and Technology on Transient Physics LaboratoryNanjing University of Science and Technology 210094 NanjingChina State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology100081 BeijingChina

Gaseous detonation propagating in a toroidal chamber was numerically studied for hydrogen/oxygen/nitrogen mixtures. The numerical method used is based on the three-dimensional Euler equations with detailed finiterate chemistry. The results show that the calculated streak picture is in qualitative agreement with the picture recorded by a high speed streak camera from published literature. The three-dimensional flow field induced by a continuously rotating detonation was visualized and distinctive features of the rotating detonations were clearly depicted. Owing to the unconfined character of detonation wavelet, a deficit of detonation parameters was observed. Due to the effects of wall geometries, the strength of the outside detonation front is stronger than that of the inside portion. The detonation thus propagates with a constant circular velocity. Numerical simulation also shows three-dimensional rotating detonation structures, which display specific feature of the detonation- shock combined wave. Discrete burning gas pockets are formed due to instability of the discontinuity. It is believed that the present study could give an insight into the interest- ing properties of the continuously rotating detonation, and is thus beneficial to the design of continuous detonation propulsion systems.

关键词： Continuously rotating detonation - Three- dimensional flow field structure - Numerical study Detonation parameters deficit ~ Effects of wall geometries

基于摆锤法的成熟期油菜角果炸荚因素试验分析

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农机化研究 2025年第4期47卷 180-185页

作者：李港张敏魏德欣江东农业农村部南京农业机械化研究所南京210014

为了降低油菜联合收割机拨禾轮拨禾过程对角果打击造成的炸荚损失,采用摆锤法模拟拨禾轮拨禾对油菜角果冲击过程,对影响拨禾过程中的炸荚因素进行测试分析,并对角果损伤变化形式及过程进行分析。试验结果表明:摆锤冲击速度3.5 m/s、夹... 详细信息

为了降低油菜联合收割机拨禾轮拨禾过程对角果打击造成的炸荚损失,采用摆锤法模拟拨禾轮拨禾对油菜角果冲击过程,对影响拨禾过程中的炸荚因素进行测试分析,并对角果损伤变化形式及过程进行分析。试验结果表明:摆锤冲击速度3.5 m/s、夹持果柄位置距连接点2 mm是区分角果抗打击炸荚的最优参数;油菜角果炸荚不仅与冲击速度、果柄夹持位置有关,而且与油菜品种、冲击件材料类型、角果受力面、含水率、角果在植株上的分布位置等都有关系;冲击速度不超过1.5 m/s时,角果损伤以角果果柄发生塑性变形为主;冲击速度为2.5~4.5 m/s时,角果损伤以果皮破裂分离、果柄弹性变形为主。研究结果可为油菜拨禾轮设计和工作参数选择提供参考。

关键词：油菜角果炸荚率冲击拨禾轮摆锤法

Investigating the Absorption and Desorption Behavior of Methylene Chloride in the Poly(aryl ether ketone) Film with Different Crystallinities

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Chinese Journal of Polymer Science 2024年第2期42卷 239-246,I0009页

作者： Hong-Ru Yang Jin-dong Zhang dong-Ting Gao gang Liu chun-Hai Chen Jia-Nan Yao Center for Advanced Low-Dimension Materials State Key Laboratory for Modification of Chemical Fibers and Polymer MaterialsCollege of Materials Science and EngineeringDonghua UniversityShanghai201620China

Poly(aryl ether keton e)(PAEK) films with different crystallinities were obtained by controlling the cooling rate,which were subjected to the absorption and desorption of methylene chloride(CH_(2)Cl_(2)).We employed attenuated total reflection Fourier transform infrared(ATR-FTIR)spectroscopy analyses to investigate the diffusion behavior of CH_(2)Cl_(2) in PAEK films with different *** to the Fickian diffusion model,the calculated diffu sion coefficients of CH_(2)Cl_(2) in PAEK films were observed to decrease with increasing *** effect of CH_(2)Cl_(2)absorption and desorption on the mechanical properties of PAEK films with different crystallinity was further analyzed using tensile *** tensile tests exhibited that CH_(2)Cl_(2) has two concurrent effects:plasticization and solvent-induced *** scanning calorimetry(DSC) and wide-angle X-ray diffraction(WXRD) techniques further confirmed solvent-induced crystallization *** results would be beneficial to understand the solvent resistance of PAEK materials and consequently provide the practical application conditions of PAEK with a theoretical basis.

关键词： Poly(aryl ether ketone) Diffusion behavior Infrared spectra Solvent-induced crystallization Mechanical properties

Bayesian empirical likelihood and variable selection for censored linear model with applications to acute myelogenous leukemia data

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International Journal of Biomathematics 2019年第5期12卷 43-61页

作者： chun-Jing Li Hong-Mei Zhao Xiao-gang dong School of Mathematics Jilin University Jilin Changchun 130012P.R.China School of Mathematics and Statistics Changchun University of Technology Jilin Changchun 130012 P.R.China

This paper develops the Bayesian empirical likelihood (BEL) method and the BEL vari-able selection for linear regression models with censored *** likelihood is a multivariate analysis tool that has been widely applietl to many fieltls such as biomed-ical and social *** introducing two special priors to the empirical likelihood function,we find two obvious superiorities of the BEL methods,that is (i) more precise coverage probabilities of the BEL credible region and (ii) higher accuracy and correct identification rate of the BEL model selection using an hierarchical Bayesian models *** current methods such as the LASSO,A LASSO and *** numerical simu-lations and empirical analysis of two data examples show strong competitiveness of the proposed method.

关键词： Bayesian empirical likeliliood censored linear regression coverage probabili-ties spike-and-slab prior

Effect of chemical reactivity on the detonation initiation in shock accelerated flow in a confined space

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Acta Mechanica Sinica 2013年第1期29卷 54-61页

作者： Yue-Jin Zhu gang dong Yi-Xin Liu Bao-chun Fan Hua Jiang State Key Laboratory of Transient Physics Nanjing University of Science and Technology State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology

The interactions of a spherical flame with an incident shock wave and its reflected shock wave in a confined space were investigated using the three-dimensional reactive Navier-Stokes equations, with emphasis placed on the effect of chemical reactivity of mixture on the flame distortion and detonation initiation after the passage of the reflected shock wave. It is shown that the spatio-temporal characteristics of detonation initiation depend highly on the chemi- cal reactivity of the mixture. When the chemical reactivity enhances, the flame can be severely distorted to form a reactive shock bifurcation structure with detonations initiating at different three-dimensional spatial locations. Moreover, the detonation initiation would occur earlier in a mixture of more enhanced reactivity. The results reveal that the detona- tions arise from hot spots in the unburned region which are initiated by the shock-detonation-transition mechanism.

关键词： Chemical reactivity Reactive shock bifurcation structure ~ Detonation initiation Hot spot Shock wave

Phenylalanine ammonia-lyase gene families in cucurbit species: Structure, evolution, and expression

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Journal of Integrative Agriculture 2016年第6期15卷 1239-1255页

作者： dong chun-juan CAO Ning ZHANG Zhi-gang SHANG Qing-mao Institute of Vegetables and Flowers Chinese Academy of Agricultural SciencesKey Laboratory of Horticultural Crop Biology and Germplasm Innovation Ministry of Agriculture

Phenylalanine ammonia-lyase （PAL）, the first enzyme of phenylpropanoid pathway, is always encoded by multigene families in plants. In this study, using genome-wide searches, 13 PAL genes in cucumber （CsPAL1-13） and 13 PALs in melon （Cm- PALl-13） were identified. In the corresponding genomes, ten of these PAL genes were located in tandem in two clusters, while the others were widely dispersed in different chromosomes as a single copy. The protein sequences of CsPALs and CmPALs shared an overall high identity to each other. In our previous report, 12 PAL genes were identified in watermelon （CIPAL1-12）. Thereby, a total of 38 cucurbit PAL members were included. Here, a comprehensive comparison of PAL gene families was performed among three cucurbit plants. The phylogenetic and syntenic analyses placed the cucurbit PALs as 11 CsPAL-CmPAL-CIPAL triples, of which ten triples were clustered into the dicot group, and the remaining one, CsPAL1-CmPAL8-CIPAL2, was grouped with gymnosperm PALs and might serve as an ancestor of cucurbit PALs. By comparing the syntenic relationships and gene structure of these PAL genes, the expansion of cucurbit PAL families might arise from a series of segmental and tandem duplications and intron insertion events. Furthermore, the expression profiling in different tissues suggested that different cucurbit PALs displayed divergent but overlapping expression profiles, and the CsPAL-CmPAL-CIPAL orthologs showed correlative expression patterns among three cucurbit plants. Taken together, this study provided an extensive description on the evolution and expression of cucurbit PAL gene families and might facilitate the further studies for elucidating the functions of PALs in cucurbit plants.

关键词： phenylalanine ammonia-lyase (PAL) gene family cucurbit evolution expression

Atmospheric Corrosion of Q235 Carbon Steel and Q450 Weathering Steel in Turpan,China

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Journal of Iron and Steel Research International 2016年第10期23卷 1061-1070页

作者： Qiang YU Chao-fang dong Yue-hua FANG Kui XIAO chun-yun GUO gang HE Xiao-gang LI Corrosion and Protection Center Key Laboratory for Corrosion and Protection University of Science and Technology Beijing Beijing 100083 China Xinjiang Turpan Natural Environmental Test Research Center Turpan 838200 Xinjiang China

Q235carbon steel and Q450 weathering steel were exposed to the hot and dry environment of Turpan,China for three *** corrosion rates of both steels were calculated and *** morphologies of the rust layer products were observed by optical microscopy and scanning electron *** of the rust layers were performed by X-ray photoelectron spectroscopy,X-ray powder diffraction,and Raman spectroscopy,and analysis results indicate that the compositions of rust are main iron rich oxide such as FeOOH,Fe_3O_4,and Fe_2O_*** iron oxide layer content proportion was calculated through a semi-quantitative *** resistance elements（Cr,Ni,and Cu）enhanced the resistance properties of the Q450 weathering steel ***,the resistance elements increased the proportion of goethite crystals in the corroded rust layer.

关键词： atmospheric corrosion Q235 carbon steel Q450 weathering steel rust layer