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Numerical study on similarity of plume infrared radiation between reduced-scale solid rocket motors

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Chinese Journal of Aeronautics 2016年第4期29卷 924-933页

作者： zhang xiaoying Chen Huandong Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen University School of Electricity South China University of Technology

This study seeks to determine the similarities in plume radiation between reduced and full-scale solid rocket models in ground test conditions through investigation of flow and radiation for a series of scale ratios ranging from 0.1 to 1. The radiative transfer equation (RTE) considering gas and particle radiation in a non-uniform plume has been adopted and solved by the finite volume method (FVM) to compute the three dimensional, spectral and directional radiation of a plume in the infrared waveband 2-6 mu m. Conditions at wavelengths 2.7 mu m and 4.3 mu m are discussed in detail, and ratios of plume radiation for reduced-scale through full-scale models are examined. This work shows that, with increasing scale ratio of a computed rocket motor, area of the high-temperature core increases as a 2 power function of the scale ratio, and the radiation intensity of the plume increases with 2-2.5 power of the scale ratio. The infrared radiation of plume gases shows a strong spectral dependency, while that of Al2O3 particles shows spectral continuity of gray media. Spectral radiation intensity of a computed solid rocket plume's high temperature core increases significantly in peak radiation spectra of plume gases CO and CO2 center dot Al2O3 particles are the major radiation component in a rocket plume. There is good similarity between contours of plume spectral radiance from different scale models of computed rockets, and there are two peak spectra of radiation intensity at wavebands 2.7-3.0 lm and 4.2-4.6 lm. Directed radiation intensity of the entire plume volume will rise with increasing elevation angle. (C) 2016 Chinese Society of Aeronautics and Astronautics. Production and hosting by Elsevier Ltd.

关键词： Infrared radiation Plume Reduced-scale model Similarity Solid rocket motor

ON BLOCK PRECONDITIONERS FOR PDE-CONSTRAINED OPTIMIZATION PROBLEMS

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Journal of Computational Mathematics 2014年第3期32卷 272-283页

作者： xiaoying zhang Yumei Huang School of Mathematics and Statistics Lanzhou University Lanzhou 730000 China

Recently, Bal proposed a block-counter-diagonal and a block-counter-triangular precon- ditioning matrices to precondition the GMRES method for solving the structured system of linear equations arising from the Galerkin finite-element discretizations of the distributed control problems in （Computing 91 （2011） 379-395）. He analyzed the spectral properties and derived explicit expressions of the eigenvalues and eigenvectors of the preconditioned matrices. By applying the special structures and properties of the eigenvector matrices of the preconditioned matrices, we derive upper bounds for the 2-norm condition numbers of the eigenvector matrices and give asymptotic convergence factors of the preconditioned GMRES methods with the block-counter-diagonal and the block-counter-triangular pre- conditioners. Experimental results show that the convergence analyses match well with the numerical results.

关键词： PDE-constrained optimization GMRES method Preconditioner Condition number Asymptotic convergence factor.

The Correlation between Density and Low-Temperature Creep Property of Asphalt

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China Petroleum Processing & Petrochemical Technology 2012年第2期14卷 31-38页

作者： zhang xiaoying Xu Chuanjie State Key Laboratory of Heavy Oil China University of PetroleumDongying 257061 Shtar Science&Technology Group China University of PetroleumDongying 257061

The density of asphalt was measured with the pycnometer and densitometer. Creep properties of the asphalt were investigated with the bending beam rheometer at temperatures ranging from 0 ~C to -36 ~C. The asphalt density data used to correlate with the creep properties were calculated from the regression equation of density and temperature. The asphalt sample used to determine the creep property was aged by the standard RTFOT test and the PAV test. The test results showed that the asphalt density had a linear relationship with temperature changes. The logarithm of the creep stiffness and the slope of the logarithm of the stiffness at 60 seconds all demonstrated a linear relationship with the density, and the regression coefficient of these data was around 0.99. The creep stiffness and the slope of the creep stiffness can be calculated from the asphalt density at the same temperature.

关键词： asphalt density creep stiffness low-temperature property

The Mechanism of Asphalt Modification by Crumb Rubber

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China Petroleum Processing & Petrochemical Technology 2012年第3期14卷 39-43页

作者： zhang xiaoying Xu Chuanjie State Key Laboratory of Heavy Oil China University of Petroleum Shtar Science&Technology Group China University of Petroleum

To investigate the mechanism of asphalt modification by crumb rubber,the interactions between FCC slurry and rubber particles were evaluated at different temperatures and *** rules of the change in mass of SARA composition in FCC slurry were obtained before and after its interaction with rubber particles,which showed that crumb rubber not only absorbed saturates and aromatics but also *** promoted the desulfurization or degradation of crumb rubber during the interaction between asphalt and crumb rubber.

关键词： asphalt crumb rubber mechanism modification SARA composition

Social Construction Functions of Consumption Space under Stratification:The Case of Guangzhou

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Chinese Geographical Science 2010年第5期20卷 450-460页

作者： LIN Geng WANG Lianjun zhang xiaoying Department of Urban and Regional Planning/Center for Urban and Regional Studies School of Geography and Planning SUN Yat-Sen University Guangzhou 510275 China

As Chinese cities rapidly transformed themselves into consumerist societies,the relationship between consumers and consumption space under stratification has become a new research area in the field of urban social *** on a consumer behavior analysis,this study explores the relationship between consumption space and the social strata of consumers in typical shopping malls in Guangzhou where the first shopping mall in China was *** result shows that shopping malls have performed significant constructive functions of organizing consumers from different social classes into different consumption *** middle-and upper-class consumers,the function of shopping malls centers on utilitarian consumption,identity recognition,and identity construction;whereas for lower-class consumers,its function revolves around pleasure and *** symbolism of consumption space is the underlying reason for shopping malls to have their social constructive *** findings of this research suggest that:1) a shopping mall is a productive consumption space and a geographical space with subjectivity;2) the micro-location of a shopping mall has social construction function;and 3) symbolic consumption is the core of social construction.

关键词： consumption space stratification shopping mail social construction social identity symbolic consumption

Effect of Polyaniline/manganese Dioxide Composite on the Thermoelectric Effect of Cement-based Materials

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Journal of Wuhan University of Technology(Materials Science) 2023年第1期38卷 109-116页

作者：季涛 LIAO Xiao HE Yan 张士萍 zhang xiaoying zhang Xiong LI Weihua School of Architecture and Civil Engineering Nanjing Institute of TechnologyNanjing 211167China College of Civil Engineering Qingdao University of TechnologyQingdao 266033China School of Civil Engineering Suzhou University of Science and TechnologySuzhou 215011China School of Materials Science and Engineering Tongji UniversityShanghai 201804China School of Chemical Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China

To enhance the thermoelectric effect of cement-based materials,conductive polyaniline(PANI)modified MnO_(2)powder was synthesized and used as a thermoelectric component in the cement *** nanostructured PANI was deposited on the surface of the nanorod-shapedα-MnO_(2)particle and the weight ratio of PANI to MnO_(2)was 22.3:77.7 in the *** synthesized PANI/MnO_(2)composite was nanostructured according to the SEM *** test results of the thermoelectric properties proved that the PANI/MnO_(2)composite was effective as the Seebeck coefficient and electrical conductivity values of the cement composites with PANI/MnO_(2)inside were 3-4 orders of magnitude higher than those of pure cement paste and the thermal conductivity values of these cement samples were *** obtained maximum figure of merit(ZT)value(2.75×10^(-3))was much larger than that of conductive materials reinforced cement-based *** thermoelectric effect of cement composites is mainly enhanced by the increased Seebeck coefficient and electrical conductivity in this work.

关键词： PANI/MnO_(2)composite cement composites thermoelectric effect Seebeck coefficient electrical conductivity

Scutellarin alleviates complete freund’s adjuvant-induced rheumatoid arthritis in mice by regulating the Keap1/Nrf2/HO-1 pathway

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BIOCELL 2023年第6期47卷 1307-1316页

作者： JIAN LI QINGQING WANG xiaoying zhang Department of Pharmacy The First People’s Hospital of Xiaoshan DistrictXiaoshan Affiliated Hospital of Wenzhou Medical UniversityHangzhou311201China Department of Nursing Community Healthcare Center of Shushan StreetHangzhou311201China

Scutellarin(SCU)is a herbal flavonoid glucuronide with multiple pharmacological activities,including antioxidant,anti-inflammation,vascular relaxation,anti-platelet,and myocardial ***,the effect of SCU on complete Freund’s adjuvant(CFA)-induced rheumatoid arthritis(RA)had not been *** this study,we investigated the beneficial effects of SCU in the CFA-induced RA mice model and the anti-arthritic activity was evaluated by paw ***-linked immunosorbent assay(ELISA)was carried out to evaluate the plasma levels of immunoglobulin(Ig)G,IgE,tumor necrosis factor(TNF)-α,interleukin(IL)-1β,IL-6,receptor activator of nuclear factor-κB ligand(RANKL),and osteoprotegerin(OPG).Histological slides were prepared from the harvested paws of mice to determine the pathological changes in the *** proportions of T helper type 1(Th1)and T helper type 2(Th2)cells of CD4+T lymphocyte subsets were analyzed by flow *** expression of Kelch-like ECHassociated protein 1(Keap1),nuclear factor erythroid 2-related factor 2(Nrf2),and heme oxygenase-1(HO-1)was analyzed using real-time quantitative PCR(RT-qPCR)and western blotting *** present study demonstrated that SCU prevented CFA-induced RA,and inhibited the expression of inflammation factors,IgG,IgE,TNF-α,IL-1β,and *** SCU also reduced the RANKL level,it increased OPG expression in RA *** Th1/Th2 ratio was significantly lower in mice treated with ***,HO-1 expression was reduced while the expression of Keap1 and Nrf2 was elevated following SCU *** provide preliminary evidence to employ SCU in arthritis treatment which might be related to the regulation of Th1/Th2 balance and the Keap1/Nrf2/HO-1 pathway.

关键词： Scutellarin Rheumatoid arthritis Th1/Th2 balance Keap1/Nrf2/HO-1 pathway Immunosuppression

An analytical approximation of focusing-wave-induced load on a semi-submerged cylinder

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Acta Oceanologica Sinica 2018年第7期37卷 85-104页

作者： HU Zhe zhang xiaoying LI Yan LI Xiaowen Key Laboratory of Fujian Province for Ships and Ocean Engineering Jimei University School of Marine Engineering Jimei University

Owing to the complexity of the physical mechanisms of rouge waves,the theoretical study of the rogue-wavestructure interaction problems still makes little ***,for regular-shaped structures,it is possible to give a theoretical analysis,if a relatively simple model of the rogue waves is *** wave load,induced by a focusing wave which is known as an intuitive basic model of the rouge waves,upon a semi-submerged cylinder is studied *** focusing wave is approximate by the Gauss envelope wave,an ideal model which contains most features of the rogue *** diffraction velocity potential is derived through the separation of flow field,and the formulas of the horizontal force and bending moment are *** derived formulas are simplified appropriately,and validated through comparison against numerical *** addition,the influence of parameters,such as the focusing degree,the submerging depth and the wave focusing position,is thoroughly investigated.

关键词： focusing wave Gauss envelope semi-submerged cylinder potential theory analytical solution

A Model of Mobile P2P Network Architecture based on Agent

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China Communications 2010年第1期7卷 50-56页

作者： Fan Chunxiao Liu Jie zhang xiaoying Gong Changlu Beijing Univ Posts & Telecommun Sch Elect Engn Beijing 100876 Peoples R China

A model of mobile peer to peer (P2P) network architecture based on agent for mobile value-added services is proposed in this paper. By using this model, wireless devices can build a P2P network dynamically, and then they can access and transmit information peer to peer. An ontologybased semantic information description method is also proposed for the mobile wireless devices. The merit of this method is to enhance search efficiency. Moreover, a small system, called CellChat, has been implemented based on this model in the lab environment. Experimental results are provided to show that the benefi ts of the proposed method. This method will become an effective solution for mobile value-added services in 3G network.

关键词： mobile P2P mobile value-added service agent ontology