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Pico-satellite Autonomous Navigation with Magnetometer and Sun Sensor Data

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Chinese Journal of Aeronautics 2011年第1期24卷 46-54页

作者： HAN Ke WANG Hao TU Binjie JIN Zhonghe Department of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China

This article presents a near-Earth satellite orbit estimation method for pico-satellite applications with light-weight and low-power requirements. The method provides orbit information autonomously from magnetometer and sun sensor, with an extended Kalman filter （EKF）. Real-time position/velocity parameters are estimated with attitude independently from two quantities： the measured magnitude of the Earth’s magnetic field, and the measured dot product of the magnetic field vector and the sun vector. To guarantee the filter’s effectiveness, it is recommended that the sun sensor should at least have the same level of accuracy as magnetometer. Furthermore, to reduce filter’s computation expense, simplification methods in EKF’s Jacobian calculations are introduced and testified, and a polynomial model for fast magnetic field calculation is developed. With these methods, 50% of the computation expense in dynamic model propagation and 80% of the computation burden in measurement model calculation can be reduced. Tested with simulation data and compared with original magnetometer-only methods, filter achieves faster convergence and higher accuracy by 75% and 30% respectively, and the suggested simplification methods are proved to be harmless to filter’s estimation performance.

关键词： pico-satellite autonomous navigation orbit estimation magnetometer Kalman filter

Anisotropy of Nonlinear-Optical Property of RCOB (R = Gd, Y) Crystal

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Chinese Physics Letters 2001年第3期18卷 385-387页

作者： WANG Zheng-Ping LIU Jun-Hai SONG Ren-Bo JIANG Huai-Dong ZHANG Shu-Jun FU Kun WANG Chang-Qing WANG Ji-Yang LIU Yao-Gang WEI Jing-Qian CHEN Huan-Chu SHAO Zong-Shu National Key Laboratory of Crystal Materials Shandong UniversityJi’nan 250100

The nonlinear-optical coefficients of RCOB(R=Gd,Y)crystals are *** spatial distribution of deff effective nonlinear-optical coefficient is determined *** experiments show that the maximum deff occurs at the second *** second-harmonic-generation efficiency reaches 48%for a 6 mm-long,(113.2°,47.4°)-cut GdCOB,and 41.5%for a 5mm-long,(113°,36.5°)-cut YCOB,*** intracavity frequency doubling of GdCOB is reported for the first time.

关键词： optical Crystal doubling

Experimental Investigation on Mixing Enhancement Mechanism of Turbulent Jet Flow with Tabbed Nozzle

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Transactions of Tianjin University 2008年第3期14卷 164-172页

作者：刘薇姜楠 Tianjin Key Laboratory of Modern Engineering Mechanics School of Mechanical Engineering Tianjin University

Flow visualization and hot-wire measurement techniques were combined to investigate the influence of the size and number of tabs on jet flow field and vortex structure generation mechanism. Streamwise vortices generated by the tabs of different sizes and numbers were observed from the flow visualization images. Combined with flow visualization, hot-wire measurement gave a quantitative insight of the effect of various tabbed jet flows. Instantaneous two-component velocity signals (longitudinal and transverse velocity components) at different cross sections along radius direction and streamwise direction with different tabbed jet nozzles were measured using hot-wire anemometer. Average flow field parameters of tabbed jet flow such as mean velocity, tur-bulence intensity, vorticity were analyzed and the effects of tabs with different sizes and numbers were compared with that of circular no-tab jet flow. It is revealed that the generation of a series of counter-rotating quasi-streamwise vortices, azimuthal vortices and double-row azi-muthal vortex are the reasons for mixing enhancement of tabbed turbulent jet flow.

关键词： tabbed nozzle mixing enhancement hot-wire anemometry flow visualization

Pure CO_(2) fluids in the Sarekoubu gold deposit at southern margin of Altai Mountains in Xinjiang,West china

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Chinese Science Bulletin 2005年第4期50卷 333-340页

作者： XUJiuhua DINGRufu XIEYuling ZHONGChanghua YUANXu DepartmentofResourceEngineering UniversityofScienceandTechnologyBeijingBeijing100083China BeijingInstituteofGeologyforMineralResources Beijing100012China

Sarekoubu gold deposit occurs in metamor- phosed acid volcanic rocks and volcaniclastic rocks of Devo- nian Kangbutiebao Formation along the southern margin of Altai Mountains in Xinjiang, West china. Pyritization, silici- fication and carbonatization are developed in wallrocks, and main gold mineralization stages are pyrite-quartz stage (Ⅱ) and polymetallic sulfide stage (Ⅲ). Primary fluid inclusions are often seen in main gold mineralization stages, which are almost pure CO2 liquid inclusions (LCO2) under room tem- perature with high densities of 0.85—1.07 g/cm3. CO2-rich inclusions (LCO2-LH2O) and H2O-rich inclusions (LH2O-LCO2) are subordinate. Fluid inclusions in stage Ⅰ (polymetallic sulfide stage) are more complex than in stage Ⅱ, containing CO2-CH4 system with ?78.1—?61.9℃of solid CO2 melting temperatures and ?33.7—?17.7℃ of partial homogenization temperatures. The trapping pressures of high densities are estimated to be 150—350 MPa. Laser Raman microprobe was used to confirm the composition of pure CO2 liquid in- clusions. δ C values of CO2 inclusions range from ?10.73‰ 13 to ?21.15‰, which are similar to some of fluids in the man- tle-derived minerals that contain surface organic carbon by subduction recycling. These characteristics differ from many hydrothermal gold deposits. CO2 fluids have a regiona source related to post-collisional orogeny.

关键词：阿尔泰山新疆二氧化碳有机碳流动性金沉积物变质酸火山岩矿物

Size and support effects for CO oxidation on supported Pd catalysts

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Science china Chemistry 2010年第9期53卷 2047-2056页

作者： WANG ZhaoWen,LI Bin,CHEN MingShu,WENG WeiZheng & WAN HuiLin State Key Laboratory of Physical Chemistry of Solid Surfaces National Engineering Laboratory for Green Chemical Productions of Alcohols-Ethers-Esters Department of Chemistry,College of Chemistry and Chemical Engineering,Xiamen University,Xiamen 361005,china State Key Laboratory of Physical Chemistry of Solid Surfaces Xiamen University Xiamen China National Engineering Laboratory for Green Chemical Productions of Alcohols-Ethers-Esters Xiamen University Xiamen China Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen China

Supporting Pd catalysts characterized significant different size distribution were obtained using PdCl2,[Pd(NH3)4](NO3)2 and Pd(acac)2 as ***-resolution transmission electron microscopy(TEM),X-ray diffraction(XRD),in-situ Fourier transform infrared spectroscopy(FTIR) and Raman spectroscopy were used to examine the dispersion of *** performance measurements show that the activities for CO oxidation increase as the Pd particle size decreases and the O2/CO ratio *** activities under oxygen rich conditions are significantly higher than those at near the stoichiometric *** on TiO2 prepared by the Pd(acac)2 precursor is highly dispersed,leading to a considerable activity for CO oxidation at near room *** oxidation on the 1 wt% Pd/TiO2 and under an O2/CO ratio of 1 characterized an apparent activation energy of 36.7 kJ/mol,which is closed to those reported for CO oxidation on the supported Au *** present work demonstrates a high catalytic activity of highly dispersed noble metals,and suggests a promising approach of using noble metals as catalysts with exceeding high efficiency.

关键词： noble metals supported palladium CO oxidation size effect support effect

Parallel Distributed CFAR Detection Optimization Based on Genetic Algorithm with Interval Encoding

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Chinese Journal of Aeronautics 2010年第3期23卷 351-358页

作者：于泽周荫清北京航空航天大学电子信息工程学院

Aiming at parallel distributed constant false alarm rate （CFAR） detection employing K/N fusion rule,an optimization algorithm based on the genetic algorithm with interval encoding is proposed. N-1 local probabilities of false alarm are selected as optimization variables. And the encoding intervals for local false alarm probabilities are sequentially designed by the person-by-person optimization technique according to the constraints. By turning constrained optimization to unconstrained optimization,the problem of increasing iteration times due to the punishment technique frequently adopted in the genetic algorithm is thus overcome. Then this optimization scheme is applied to spacebased synthetic aperture radar （SAR） multi-angle collaborative detection,in which the nominal factor for each local detector is determined. The scheme is verified with simulations of cases including two,three and four independent SAR systems. Besides,detection performances with varying K and N are compared and analyzed.

关键词： parallel processing systems synthetic aperture radar detectors genetic algorithms optimization encoding

A new series of two-photon polymerization initiators:Synthesis and nonlinear optical properties

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Science china Chemistry 2009年第12期52卷 2180-2185页

作者： GAN XiaoPing ZHOU HongPing SHI PengFei WANG Peng WU JieYing TIAN YuPeng YANG JiaXiang XU GuiBao ZHOU YuFang JIANG MinHua Department of Chemistry Anhui University and Key Laboratory of Functional Inorganic Materials Chemistry of Anhui ProvinceHefei 230039China Department of Applied Chemistry School of ScienceAnhui Agriculture UniversityHefei 230036China State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100China State Key Laboratory of Coordination Chemistry Nanjing UniversityNanjing 210093China

Four photopolymerization initiators with D-π-D (D,donor; π,conjugation system) structure have been synthesized by solvent-free reaction and characterized by 1H NMR spectroscopy,IR and elemental analysis. The one-photon and two-photon excited fluorescence have been investigated in different solvents. Experimental results of the one-photon and two-photon absorption cross sections show different trends in OPA and TPA ability with different substitution groups in donor units.

关键词： two-photon absorption micro-fabrication polymerization solvent-free

Ecological restoration for river ecosystems: comparing the Huangpu River in Shanghai and the Hudson River in New York

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Ecosystem Health and Sustainability 2015年第7期1卷 7-20页

作者： Xiangrong Wang Shixiong Wang Guotao Peng Daniel S.W.Katz Huanran Ling Department of Environmental Science and Engineering Fudan UniversityShanghai 200433 China Bard Center for Environmental Policy Bard CollegeP.O.Box 5000AnnandaleNew York 12504 USA Department of Earth and Environment Boston UniversityBostonMassachusetts 02215 USA

Starting in the 1960s,a great deal of effort and capital was invested in an endeavor to significantlyimprove the quality of surface water around the United States,particularly in metropolises like New YorkCity,New *** Hudson River has been at the forefront of these efforts and has benefited immenselyfrom this *** parts of the developing world,such as china,similar efforts are beginning to gatherthe same type of *** the past decade,the Huangpu River,which flows through Shanghaiinto the Yangtze Estuary of china,has been a target for ecological restoration and *** is possibleto draw parallels between the cleanup efforts involved in improving the environmental conditions of theHuangpu and Hudson *** the methodologies of series comparison(SCM),water quality index(WQI)modeling,consideration of ecological engineering,and policy strategy design,we comparativelystudied the topography,functions,environmental conditions,ecological engineering countermeasures,andmanagement policies of the two rivers to assist future forecasting of ecological restoration efforts in china.

关键词： ecological restoration Huamgpu River,china Hudson Riover,Newo York,ISA mamngement policy river ecosystem Shanghai,china water quality index(WQI)modeling

Pterocaryquinone, a Novel Naphthoquinone Derivative from Pterocarya tonkinesis

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Chinese Journal of Chemistry 2006年第12期24卷 1683-1686页

作者：刘红兵蔡兵崔承彬颐谦群赵庆春管华诗 Key Laboratory of Marine Drugs MEC Marine Drug and Food Institute Ocean University of China Qingdao Shandong 266003 China Beijing Institute of Biomedicine Beijing 100091 China Beijing Institute of Pharmacology and Toxicology Beijing 100850 China

Pterocaryquinone, a novel 1,4-naphthoquinone derivative, was isolated from Pterocarya tonkinesis and its structure was elucidated by spectroscopic methods. Pterocaryquinone is a new dimeric 1,4-naphthoquinone derivative having a pentacyclic skeleton with two five-membered carbon rings, which provided a novel structural skeleton for 1,4-naphthoquinone derivatives and showed apoptosis-inducing activity toward mouse cancer tsFT210 cells.

关键词： Pterocarya tonkinesis naphthoquinone pterocaryquinone chemical structure apoptosis