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	Global Controllability of the Navier-Stokes Equations in the Presence of Curved Boundary with No-Slip Conditions 期刊论文 OAI收割 JOURNAL OF MATHEMATICAL FLUID MECHANICS, 2022, 卷号: 24, 期号: 3, 页码: 32 作者: Liao, Jiajiang; Sueur, Franck; Zhang, Ping \| 收藏 \| 浏览/下载：22/0 \| 提交时间：2023/02/07 Axi-symmetric Navier-Stokes equations Controllability No-slip Dirichlet boundary condition Boundary layers Return method Multi-scales asymptotic expansion Well-prepared dissipation method Long-time nonlinear Cauchy-Kovalevskaya estimates
	Structure and magnetic properties of (Al, Co) Co-doped ZnO thin films (EI CONFERENCE) 会议论文 OAI收割 2012 International Conference on Materials Science and Nanotechnology, ICMSN 2012, November 16, 2012 - November 18, 2012, Guangzhou, China Cao P.; Bai Y. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 In this study Zn0.99Co0.01Al0.015O thin film has been prepared by sol-gel method. The structural and magnetic properties of the sample were investigated. X-ray diffraction spectroscopy analyses indicate that the Co and Al codoping can not disturb the structure of ZnO. No additional peaks are observed in the Zn0.99Co0.01Al xO and Al3+ and Co2+ substitute for Zn 2+ without changing the wurtzite structure. The resistance measurements confirm that Al ions increase the free carriers concentration. Based on the above experiments we think the ferromagnetic behavior of the sample could not originate from Co nanoclusters. The presence of free carriers and localized d spins is a prerequisite for the appearance of ferromagnetism. As the result the carriers generated by Al doping is considered a main factor to induce the ferromagnetic phenomenon. (2013) Trans Tech Publications Switzerland.
	Surface modification of SiC mirror by IARE method (EI CONFERENCE) 会议论文 OAI收割 7th International Conference on Thin Film Physics and Applications, September 24, 2010 - September 27, 2010, Shanghai, China 作者: Gao J. 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/03/25 A method to prepare high quality SiC coating at low temperature using large aperture E-beam evaporation PVD equipment with ion assistance was developed for the surface modification of SiC mirror for space projects. This method was called Ion Assisted Reactive Evaporation (IARE). The modified SiC coating was prepared using CH4 and Si with Kaufman ion source by IARE at 300C and it had met the requirements of applications. The SiC coating prepared by this method was amorphous. It was dense homogeneous and easy to be polished. The surface modification of a SiC mirror was carried out using SiC coating by this method and achieved a fine surface modification effect. The surface roughness (rms) of the SiC substrate was reduced to 0.862nm the scattering coefficient was reduced to 2.79% and the reflectance coated with Ag film was improved simultaneously after the surface modification. The effect of surface modification using SiC coating was close to that of using Si coating. It can be drawn that this technological method to preparation SiC coating for the surface modification of SiC mirror is reasonable and effective. 2011 SPIE.
	Earth elevation map production and high resolution sensing camera imaging analysis (EI CONFERENCE) 会议论文 OAI收割 Optoelectronic Imaging and Multimedia Technology, October 18, 2010 - October 20, 2010, Beijing, China 作者: Dai L. 收藏 \| 浏览/下载：141/0 \| 提交时间：2013/03/25 The Earth's digital elevation which impacts space camera imaging has prepared and imaging has analysed. Based on matching error that TDI CCD integral series request of the speed of image motion statistical experimental methods-Monte Carlo method is used to calculate the distribution histogram of Earth's elevation in image motion compensated model which includes satellite attitude changes orbital angular rate changes latitude longitude and the orbital inclination changes. And then elevation information of the earth's surface from SRTM is read. Earth elevation map which produced for aerospace electronic cameras is compressed and spliced. It can get elevation data from flash according to the shooting point of latitude and longitude. If elevation data between two data the ways of searching data uses linear interpolation. Linear interpolation can better meet the rugged mountains and hills changing requests. At last the deviant framework and camera controller are used to test the character of deviant angle errors TDI CCD camera simulation system with the material point corresponding to imaging point model is used to analyze the imaging's MTF and mutual correlation similarity measure simulation system use adding cumulation which TDI CCD imaging exceeded the corresponding pixel horizontal and vertical offset to simulate camera imaging when stability of satellite attitude changes. This process is practicality. It can effectively control the camera memory space and meet a very good precision TDI CCD camera in the request matches the speed of image motion and imaging. 2010 SPIE.
	Synthesis, morphology and optical properties of SrTiO3:Pr 3+ phosphors (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Functional Materials 2009, ISFM 2009, June 15, 2009 - June 18, 2009, Jinju, Korea, Republic of 作者: Li W.; Li W. 收藏 \| 浏览/下载：24/0 \| 提交时间：2013/03/25 SrTiO3:Pr3+ phosphors with different morphologies were prepared by using high-temperature solid-state reaction the solvothermal method and sol-gel synthesis. All the products were systematically characterized by powder x-ray diffraction (XRD) infrared spectroscopy (IR) scanning electron microscopy (SEM) photoluminescence (PL) and photoluminescent excitation spectra (PLE). The influence of different synthesis methods on the morphology and optical properties of SrTiO3:Pr3+ was discussed. 2010 The Royal Swedish Academy of Sciences.
	Manufacture of 1.2m reaction bonded silicon carbide mirror blank CFID (EI CONFERENCE) 会议论文 OAI收割 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, April 26, 2010 - April 29, 2010, Dalian, China 作者: Zhang G.; Zhang G.; Zhang G. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 Silicon carbide (SiC) is a new type candidate material for large-scale lightweight space mirror. Its low thermal distortion high stiffness fine optical quality and dimensional stability make SiC an ideal material for large space born telescope. Since ten years Changchun institute optics fine mechanics and physics (CIOMP) has developed reaction bonded SiC (RB-SiC) technology for space application and can fabricate RB-SiC mirror with scale less than 1.0 meter for telescope. The green body is prepared with gel-casting method which is an attractive new ceramic forming process for making high-quality complex-shaped ceramic parts. And then unmolding drying binder burning out reacting bonded the RB-SiC can be obtained. But with the development of space-born or ground telescope the scale of primary mirror has exceeded 1.0 meter. So CIOMP has developed an assembly technique which called novel reaction-formed joint technology for larger RB-SiC mirror blank. The steps include joining of green bodies with mixture comprised of SiC particles and phenolic resin etc firing machining and sintering. Joining the 1.2 meter RB-SiC mirror blank by the novel reaction-formed joint technology. And testing the welding layer's performance the results show that the thickness of 54-77m the microstructure and thermal property can be comparable to the substrate and the mechanical property are excellent in bending strength of 307MPa. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Fabrication technique of large-scale lightweight SiC space mirror (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Large Mirrors and Telescopes, July 8, 2007 - July 12, 2007, Chengdu, China 作者: Zhang G.; Zhang G.; Zhang G. 收藏 \| 浏览/下载：21/0 \| 提交时间：2013/03/25 Silicon carbide (SiC) is a new type candidate material for large-scale lightweight space mirror. Its low thermal distortion high stiffness high optical quality and its dimensional stability are better than other traditional optical substrate materials such as ULE Zerodure Beryllium (Be) and so on. In this paper the lightweight silicon carbide space mirror blank was fabricated by reaction sintering. As a space born mirror material silicon carbide must be an optical grade ceramic. So we prepared the silicon carbide green body with gel-casting method. Then some carbon materials were supplemented into the green body which will bring reaction-sintering with silicon in a vacuum furnace during 1500-1600C ultimately the reaction bonded silicon carbide was made. The diameter of SiC space mirror blank we have made is 680mm. If expanding the size of the vacuum furnace bigger mirror blank can be obtained. The test results show that the mechanical and thermal properties of RB-SiC are excellent with bending strength of 350MPa fracture toughness of 4.1 MPa·m1/2 and coefficient of thermal expansion(CET) of 2.6710-6/K. The surface roughness(RMS) could be better than 3nm.
	Comparative study on oxidation of methane to ethane and ethylene over na2wo4-mn/sio2 catalysts prepared by different methods 期刊论文 iSwitch采集 Journal of molecular catalysis a-chemical, 2006, 卷号: 245, 期号: 1-2, 页码: 272-277 作者: Wang, JX; Chou, LJ; Zhang, B; Song, HL; Zhao, J 收藏 \| 浏览/下载：22/0 \| 提交时间：2019/05/10 Na2wo4-mn/sio2 catalyst Oxidative coupling of methane Prepared method
	Comparative study on oxidation of methane to ethane and ethylene over Na2WO4–Mn/SiO2 catalysts prepared by different methods 期刊论文 OAI收割 Journal of Molecular Catalysis A: Chemical, 2006, 卷号: 245, 页码: 272-277 作者: Song HL(宋焕玲); Zhao J(赵军) 收藏 \| 浏览/下载：23/0 \| 提交时间：2014/01/10 Na2WO4–Mn/SiO2 catalyst Oxidative coupling of methane Prepared method