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Remote sensing based shrub above-ground biomass and carbon storage mapping in Mu Us desert,china

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Science china(Technological Sciences) 2010年第S1期53卷 176-183页

作者： XU Min 1.2,CAO ChunXiang 1.TONG QingXi 1.li ZengYuan 3,ZHANG Hao 1.HE QiSheng 1.2,GAO MengXu 1.2,{1. Jian 1.2,ZHENG Sheng 1.2,CHEN Wei 1.2.& ZHENG LanFen 1.1.tate Key Laboratory of Remote Sensing Science,Jointly Sponsored by the {14. of Remote Sensing Applications of chinese academy of Sciences and Beijing Normal University,Beijing 1.01.1.china 2 Graduate School of the chinese academy of Sciences,Beijing 1.004.,china 3 Research {14. of Forest Resources and Information Techniques,chinese academy of Forestry,Beijing 1.009,china 1. State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China 2. Graduate School of the chinese {1. of Sciences Beijing 100049 China 3. Research institute of Forest Resources and Information Techniques Chinese Academy of Forestry Beijing 10009 China

The estimation of above-ground biomass(AGB) and carbon storage is very important for arid and semi-arid ***-1./B satellite data combined with field measurement data was used for the estimation of shrub AGB and carbon storage in the Mu Us desert,*** correlations of shrub AGB and spectral reflectance of four bands as well as their combined vegetation indexes were respectively analyzed and stepwise regression analysis was employed to establish AGB prediction *** prediction equation based on ratio vegetation index(RVI)was proved to be more suitable for shrub AGB estimation in the Mu Us desert than *** AGB and carbon storage were mapped using the RVI based prediction model in *** statistics showed the western Mu Us desert has relatively high AGB and carbon storage,and that the gross shrub carton storage in Mu Us desert reaches 1. 799 {4.0 t,which has greatly contributed to the carbon fixation in northern china.

关键词： above-ground biomass carbon storage Mu Us desert HJ-1./B remote sensing

Theoretical study on the reaction mechanism of(CH_3)_3CO+CO

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Science china Chemistry 2005年第1期48卷 18-24页

作者： zhao Hongmei1.2.3, SUN Chengke1.4. ZHANG Rongchang3, XI Hongmin3 & {1. Zonghe1.1. Department of Chemistry, Beijing Normal University, Beijing 1.0875, china 2. The Laboratory of Molecular Reaction Dynamics, institute of Chemistry, chinese academy of Sciences, Beijing 100080, china 3. Department of Chemistry, Beihua University, Ji{1.n 1.2.1., china 4. Department of Chemistry, Qujing Normal University, Yunnan 655000, china 1. Department of Chemistry Beijing Normal University 100875 Beijing China 2. The Laboratory of Molecular Reaction Dynamics Institute of Chemistry Chinese Academy of Sciences 100080 Beijing China 3. Department of Chemistry Beihua University 132013 Jilin China 4. Department of Chemistry Qujing Normal University 655000 Yunnan China

The reaction mechanism of (CH3)3CO with CO has been theoretically investigated using density-functional theory (DFT) calculations at B3LYP/6-31.* level. In order to get more reliable energy values the single-point energy is evaluated at CCSD (T)/6-31.+G** level. The results show that the reaction is multi-channel and the reaction of (CH3)3CO radical with CO mostly produces (CH3)3C + CO2. The reaction could play a role in eliminating air pollution.

关键词： DFT, B3LYP, (CH3)3CO, radical.

Characteristics of InGaN multiple quantum well blue-violet laser diodes

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Science china(Technological Sciences) 2006年第6期49卷 727-732页

作者： li Deyao1. ZHANG Shuming1. WANG Jianfeng1. CHEN Jun1. CHEN lianghui2. CHONG Ming2. ZHU Jianjun1. zhao Degang1. liU Zongshun1. YANG Hui1.& liANG Junwu1.1. State Key Laboratory of Integrated Optoelectronics, institute of Semiconductors, chinese academy of Sciences, Beijing 1.0083, china 2. Nano-Optoelectronics Laboratory, institute of Semiconductors, chinese academy of Sciences, Beijing 1.0083, china State Key Laboratory of Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China Nano-Optoelectronics Laboratory Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China

Studies on InGaN multiple quantum well blue-violet laser diodes have been reported. Laser structures with long-period multiple quantum wells were grown by metal-organic chemical vapor deposition. Triple-axis X-ray diffraction (TAXRD) measurements show that the multiple quantum wells were high quality. Ridge waveguide laser diodes were fabricated with cleaved facet mirrors. The laser diodes lase at room temperature under a pulsed current. A threshold current density of 3.3 kA/cm[2.; a characteristic temperature T 0 of 1.5 K were observed for the laser diode.

关键词： metalorganic chemical vapor deposition (MOCVD), GaN-based laser diodes, multiple quantum well, ridge waveguide, threshold current.

Adsorption behavior of hexadecyltrimethylammonium bromide (CTAB) to mica substrates as observed by atomic force microscopy

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Science china Chemistry 2005年第2期48卷 101-106页

作者： zhao Feng1.2. DU Yukou1. YANG Ping1. {1. Xingchang2.& TANG Ji’an2.1. Chemistry and Chemical Engineering Department, Suzhou University, Suzhou 2.1}006, china 2. Key Laboratory of Colloid and Interface Science, institute of Chemistry, chinese {14. of Sciences, Beijing {12., china Correspondence should be addressed to Tang Ji’an (email: jatang@***) 1. Chemistry and Chemical Engineering Department Suzhou University 215006 Suzhou China 2. Key Laboratory of Colloid and Interface Science Institute of Chemistry Chinese Academy of Sciences 100080 Beijing China

Atomic force microscopy is employed to study the adsorption behavior of CTAB to mica surfaces. Results show that conformational transitions from globular micelles→cylindrical micelles→flat films are observed in the process of the adsorption of CTAB to mica at twice the bulk critical concentration. However, in 0.5 cmc CTAB solution, the adsorbed CTAB molecules to mica form the layered film structures, and apparent conformational transitions do not appear. Meanwhile, the phenomena of the adsorption of CTAB to mica and the dissociation of mica sur- faces are periodically observed.

关键词： atomic force microscopy (AFM), micelle, behavior of adsorption, the dissociation of mica surfaces.

On-line matrix addition for detecting aerosol particles

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Science china(Physics,Mechanics & Astronomy) 2006年第2期49卷 187-194页

作者： ZHOU liuzhu1.2. ZHU Yuan1. GUO Xiaoyong1. {1. Wenwu1. ZHENG Hai-yang1. Gu Xuejun1. FANG li1.& ZHANG Weijun1.1. Lab of Environmental Spectroscopy, Anhui {12. of Optics and Fine Mechanics, {14. academy of Sciences, Hefei 2.0031. china 2. Qufu Normal University, Qufu 2.31.5, china 1. Lab of Environmental Spectroscopy Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences Hefei 230031 China 2. Qufu Normal University Qufu 273165 China

Single aerosol particles were measured by matrix-assisted laser desorp-tion/ionization (MALDI) with an aerosol time-of-flight mass spectrometer (ATOFMS). The inlet to the ATOFMS was coupled with an evaporation/condensation flow cell that allowed matrix addition by condensation onto the particles. The coated particles entered the ion source through three-stage differentially pumped capillary inlet and were then ionized by a focused 2.6 nm Nd:YAG laser. The mass spectra and aerodynamic size of the single particles can be obtained simultaneously. The on-line matrix addition technique makes it possible to identify biological aerosols in real-time.

关键词： ATOFMS evaporation/condensation MALDI.

Development of solar-blind AlGaN 1.8x1.8 Ultraviolet Focal Plane Arrays

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Science china(Technological Sciences) 2008年第6期51卷 820-826页

作者： YUAN YongGang1. ZHANG Yan1. CHU KaiHui1. li XiangYang1. {1. DeGang2.& YANG Hui2.1.State Key Laboratories of Transducer Technology, Shanghai institute of Technical Physics, chinese academy of Sciences, Shanghai 2.0083, china 2.institute of Semiconductors, chinese academy of Sciences, Beijing 1.0083, china State Key Laboratories of Transducer Technology Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai 200083 China institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China

This paper reports the development of solar-blind aluminum gallium nitride (AlGaN) {2.8×{2.8 UV Focal Plane Arrays (FPAs). The back-illuminated hybrid FPA archi- tecture consists of an {2.8x{2.8 back-illuminated AlGaN PIN detector array that is bump-mounted to a matching {2.8x{2.8 silicon CMOS readout integrated circuit (ROIC) chip. The {2.8×{2.8 p-i-n photodiode arrays with cuton and cutoff wave-lengths of 2.3 and 2.8 nm, with a sharp reduction in response to UVB (2.0―32. nm) light. Several examples of solar-blind images are provided. This solar-blind band FPA has much better application prospect.

关键词： AlGaN photodiode ultraviolet FPA solar-blind

Stochastic structural model of rock and soil aggregates by continuum-based discrete element method

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Science china(Technological Sciences) 2005年第z1期48卷 95-106页

作者： WANG Yuannian1. zhao Manhong1. {1. Shihai1.& J.G. Wang2.0} institute of Mechanics, chinese academy of Sciences, Beijing 100080, china 2. Tropical Marine Science institute, National University of Singapore, 1. Kent Ridge Crescent, Singapore 1.92.0 1. institute of Mechanics Chinese Academy of Sciences 100080 Beijing China 2. Tr?pical Marine Science institute National University of Singapore 10 Kent Ridge Crescent 119260 Singapore

This paper first presents a stochastic structural model to describe the random geometrical features of rock and soil aggregates. The stochastic structural model uses mixture ratio, rock size and rock shape to construct the microstructures of aggregates, and introduces two types of structural elements (block element and jointed element) and three types of material elements (rock element, soil element, and weaker jointed element) for this microstructure. Then, continuum-based discrete element method is used to study the deformation and failure mechanism of rock and soil aggregate through a series of loading tests. It is found that the stress-strain curve of rock and soil aggregates is nonlinear, and the failure is usually initialized from weaker jointed elements. Finally, some factors such as mixture ratio, rock size and rock shape are studied in detail. The numerical results are in good agreement with in situ test. Therefore, current model is effective for simulating the mechanical behaviors of rock and soil aggregates.

关键词： CDEM, rock and soil aggregate, mixture ratio.

The properties of halo structure for ^(1.)B

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Science china(Physics,Mechanics & Astronomy) 2008年第7期51卷 781-787页

作者： HU ZhengGuo1. WANG Meng1. XU HuShan1. SUN ZhiYu1. WANG JianSong1. XIAO GuoQing1. ZHAN WenLong1. XIAO ZhiGang1. MAO RuiShi1.2, li Chen1. ZHANG XueYing1.2, ZHANG HongBin1. {1. TieCheng1. XU ZhiGuo1. WANG Yue1.2, CHEN RuoFu1.2, HUANG TianHeng1.2, FU Fen1.2, GAO Qi1.2, HAN JianLong1.2, ZHANG XueHeng1.2, ZHENG Chuan1.2, YU YuHong1.2.& GUO ZhongYan1.1.institute of Modern Physics, chinese academy of Sciences, Lanzhou 730000, china 2 Graduate University of the chinese academy of Sciences, Beijing 1.004., china 1. institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China 2. Graduate University of the chinese {1. of Sciences Beijing 100049 China

The total reaction cross section (1.2.±93 mb) of 1.B at the energy of 4..7 A MeV on C target has been measured by using the transmission method at the Radioactive Ion Beam {2.ne in Lanzhou (RIBLL). Assuming 1.B consists of a core 1.B plus two halo neutrons,the total cross section of 1.B on C target was calculated with the zero-range Glauber model,where double Gaussian density distributions and Gaussian plus HO density distributions were used. It can fit the experimental data very well. The characteristic of halo structure for 1.B was found with a large diffusion of the neutrons density distribution.

关键词： total cross section density distribution Glauber model the characteristic of halo structure

Fabrication of Transparent Superhydrophilic TiO_2.Nanofilm without UV-irradiation

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稀有金属材料与工程 2012年第S1期41卷 263-267页

作者： Du Wen1.2.Ye Yinping1.{2. Hongxuan1.{1. Fei1.2.Ji {2.1.Quan Weilong1.2.Chen Jianmin1.Zhou Huidi1.1.State Key Laboratory of So{2.d Lubrication,Lanzhou institute of Chemical Physics,chinese academy of Sciences,Lanzhou 730000,china 2.Graduate University of chinese academy of Science,Beijing 1.004.,china chinese Acad Sci Lanzhou Inst Chem Phys State Key Lab Solid Lubricat Lanzhou 730000 Peoples R China chinese Acad Sci Grad Univ Beijing 100049 Peoples R China

A transparent phase-pure anatase TiO2.nanofilm was prepared through magnetron sputtering method,and a subsequent annealing treatment awarded it the superhydrophilic *** make clear the mechanism of the heat-induced superhydrophilicity,the chemical composition and surface morphology of the film were investigated in detail and compared before and after the annealing treatment mainly by field emission scanning electron microscopy(FESEM),X-ray diffraction method(XRD),Raman spectroscopy,and X-ray photoelectron spectroscope(XPS).The results suggest that the probable mechanism is in accordance with the UV-induced mechanism,where the heat-induced surface oxygen vacancies and hydroxyl radicals play important roles for achieving the superhydrophilicity.

关键词： superhydrophilicity transparent TiO2 nanofilms magnetron sputtering annealing treatment