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A novel operation mode for spaceborne polarimetric SAR

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Science china(Information {1.) 2011年第4期54卷 884-897页

作者： QI WeiKong 1,2.& YU WeiDong 1 1 Institute of Electronics,chinese Academy of sciences,{2. 100190,china 2.graduate school of chinese Academy of sciences,{2. 1.0039,china 1. Institute of Electronics Chinese Academy of Sciences Beijing 100190 China2. Graduate School of Chinese Academy of Sciences Beijing 100039 China

A novel operation mode for spaceborne polarimetric SAR,named polarization space-division adding polarization code-division (PSD-PCD) operation mode,is proposed in this paper through combining polarimetric SAR with elevation digital beam-forming (DBF) on *** a pulse repetition interval the up-chirp LFM sub-pulse is transmitted with horizontal polarization antenna,and with some delay the down-chip LFM subpulse is transmitted with vertical polarization antenna to realize code *** every sub-aperture receives returns from ground,SAR system uses range DBF to separate echoes relative to different sub-pulses in order to realize space *** system PRF is equal to that of single-polarization SAR,and elevation DBF help reduce range ambiguity ***,the main system parameters,including PRF,delay between two sub-pulses,radar equation and ambiguity are analyzed and compared with those of single-polarization *** results demonstrate the feasibility and validity of PSD-PCD operation mode.

关键词： spaceborne synthetic aperture radar (SAR) polarimetry digital beamforming (DBF) operation mode ambiguity ratio polarization space-division polarization code-division

Assessing the Carrying Capacity of Tourist Resorts: An Application of Tourists’ Spatial Behavior Simulator Based on GIS and Multi-Agent System

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Wuhan University Journal of Natural sciences 2005年第4期10卷 779-784页

作者： ZHANG Ren-jun 1.2.1. Institute of Mountain Hazards and Environment, {1. Academy of sciences, Chengdu 61.041. Sichuan,{2. 2. graduated school of the {1. Academy of sciences, beijing 1.0039,{2. chinese Academy of {1. Institute of Mountain Hazards and Environment Chengdu Sichuan China (GRID:grid.9227.e) (ISNI:***) graduated {1. of the {2. Academy of sciences Beijing China (GRID:grid.9227.e) (ISNI:***)

Based on the study of visitors' individual spatial behaviors, a tourists'spatial behavior simulator (TSBS) to assess the carrying capacity of tourist resorts was developed,TSBS employs GIS (Geographic Information System) to manage the spatial data,and Multi-Agent systemto simulate the actions of individual visitors. By utilizing TSBS, visitors' travel patterns such aslocation, cost, and state can be analyzed and predicted. Based on this analysis and prediction, themodel of assessing the carrying capacity of resorts is built. Our results show that TSBS will be aneffective tool to accurately assess the carrying capacity of tourist resorts.

关键词： tourist resort carrying capacity TSBS GIS Multi-Agent simulator

Cloning and characterization of interferon stimulated genes Viperin and ISG1.,and their promoters from snakehead Channa argus

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Progress in Natural Science:Materials International 2007年第12期17卷 1425-1435页

作者： Jia Weizhang1,2. Zhou Xiuxia1,2. Huang Rong1,2.and Guo Qionglin1(1. Institute of Hydrobiololgy, chinese Academy of sciences, Wuhan 430072.{2. 2. graduate University of chinese Academy of sciences, beijing 1.0039,{2.) Institute of Hydrobiololgy Chinese Academy of Sciences Wuhan 430072 China graduate University of {1. Academy of {2. Beijing 100039 China

By suppression subtractive hybridization, rapid amplification of cDNA ends and gene walking methods, interferon stimulated genes (ISGs), Viperin and ISG1., and their promoters have been cloned and characterized from snakehead Channa argus. The Viperin cDNA was found to be 1.74 nt and contain an open reading frame (ORF) of 1.59 nt that translates into a putative peptide of 352.amino acid (aa). The putative peptide of Viperin shows high identity to that in teleosts and mammals except for the N-terminal 70 aa. The ISG1. cDNA was found to be 758 nt and contain an ORF of 468 nt that translates into a putative peptide of 1.5 aa. The putative peptide of ISG1. is composed of two tandem repeats of ubiquitin-like (UBL) domains, and a canonical conjugation motif (LRGG) at C-terminal. Viperin and ISG1. promoter regions were characterized by the presence of interferon stimulating response elements (ISRE) and γ-IFN activation sites (GAS). ISRE is a feature of IFN-induced gene promoter and partially overlaps interferon regulatory factor (IRF) 1.and IRF2.recognition sites. GAS is responsible for the γ-IFN mediated transcription. One conserved site for NF-κB was found in the promoter region of Viperin. This is the first report of conservative binding motif for NF-κB in accordance with the consensus sequence (GGGRNNYYCC) among teleost ISG promoters. Moreover, there were also TATA, CAAT and Sp1.transcription factor sites in Viperin and ISG1. promoters. In 5′ untranslated region (UTR), snakehead ISG1. gene contains a single intron, which differs from Viperin gene. The transcripts of Vipeirn and ISG1. mRNA were mainly expressed in head kidney, posterior kidney, spleen and gill. The expression levels in liver were found to increase obviously in response to induction by IFN-inducer poly I∶C.

关键词： interferon interferon stimulated gene (ISG) Viperin ISG1. snakehead (Channa argus).

Plus cupping degrees do not form an ideal

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Science in china(Series F) 2004年第5期47卷 635-654页

作者： LI Angsheng1.2.& ZHAO Yicheng1.1. Institute of Software,{1. Academy of sciences,{2. 1.0080,china 2. school of Information sciences,{2. Normal University,{2. 1.0871.china 1. Institute of Software Chinese Academy of Sciences 100080 Beijing China 2. {1. of Information sciences Beijing Normal University 100871 Beijing China

A computably enumerable (c.e.,for short)degree a is called plus cupping,if every c.e. degree x with 0 详细信息

A computably enumerable (c.e.,for short)degree a is called plus cupping,if every c.e. degree x with 0

关键词： computably enumerable set Turing degree definability.

Wet-chemical synthesis and characteristics of Au nanoshell

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Science china Chemistry 2005年第5期48卷 431-435页

作者： LIU Zhongxin1,2. SONG Hongwei1, YU Lixin1,2. YANG Linmei1,2.& PAN Guohui1,2.1. Key Laboratory of Excited State Physics, Changchun Institute of Optics, Fine Mechanics and Physics, chinese Academy of sciences, Changchun 130033,{2. 2. graduate school of the chinese Academy of sciences, beijing 1.0039,{2. 1. Key Laboratory of Excited State Physics Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences 130033 Changchun China 2. {1. school of the {2. Academy of sciences 100039 Beijing China

Gold nanoshells were prepared by an easy wet-chemical method, with Ag nanoparticles used as the templates. Transmission electron microscopy (TEM) indicated that the shells were sphere in shape, the size was homogenous, being about 2. nm, and no hard ag-glomerates were observed. The plasma resonance absorption of gold was tuned from visible to near-infrared (NIR) with the increased volume of HAuCl4. The temperature grads (?T) of the gold nanoshell hydrosol under the exposure of an 808-nm optical fiber laser with different power den-sities were measured. The highest ?T was 30℃ (5 W/cm2. irradiation area was 2.cm2.. This kind of gold nanoshell hydrosol is a promising material to be used in biomedicine such as photo-thermal cancer therapy, and its special photothermal convert property will photothermally trigger drug release.

关键词： wet-chemical synthesis, Au, nanoshell, NIR absorption, photothermal conversion.

Characteristics of chlorine isotope distribution and analysis on sylvinite deposit formation based on ancient salt rock in the western Tarim Basin

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Science china Earth {1. 2005年第11期48卷 1913-1920页

作者： TAN Hongbing1,2. MA Haizhou1, XIAO Yingkai1, WEI Haizhen1,2. ZHANG Xiying1 & MA Wandong1 1. Institute of Salt Lakes, chinese Academy of sciences, Xining 810008,{2. 2. graduate school of the chinese Academy of sciences, beijing 1.0039,{2. 1. Institute of Salt Lakes Chinese Academy of Sciences 810008 Xining China 2. {1. school of the {2. Academy of sciences 100039 Beijing China

During formation of the Tarim Basin, there repetitively happened seawater invasion for it was ever connected with wide Paleo-mediterranean Sea. At the same time, for the applica-tion of tectonic and paleoenvironmental condition, the basin deposits many sequences of thick strata of evaporites, especially in its two largest subbasins of Kuqa in the north and Shaqa in the southwest. Therefore, the western Tarim Basin has been considered to be a favorable location to prospect ancient sylvinite deposit. But it is unfortunate that the Br×1.3/Cl ratio, as a common geochemical index to uncover clues of sylvinite deposit, is almost invalid to indicate the stage of ancient brine condensation for very low content of bromine in salt rock samples (less than 1.?6 commonly) in the western Tarim Basin evaporites. Fortunately, we noticed recently that the val-ues of chlorine isotope (δ 37Cl value) for salt rock samples follow some clear laws from place to place, which in the Shaqa subbasin, all δ 37Cl values of salt rock samples behaved negatively and on the contrary, they all surprisingly showed positive values in the Kuqa subbasin. Based on conclusions of previous research and referring to the ratios of Br×1.3/Cl for salt rock or brine samples, we proved that the chlorine isotope (δ 37Cl) could be used as an effective index to find ancient sylvinite deposit in those evaporites rock basin with low content of Br element back-ground, such as the Tarim Basin. Thus according to the new index of chlorine isotope, we con-clude that the concentration of ancient brines formed ancient salt rocks is much more concen-trated in the Shaqa subbasin than that in the Kuqa subbasin. Particularly, the δ 37Cl value of salt rock in Kashi depression of the western Shaqa subbasin is greatly negative (1.00‰), which may predicate that the ancient brine has been concentrated to the terminal stage of salt deposit or even the later stage of sylvinite deposit. Then it is possible to find sylvinite-bearing d

关键词： the Tarim Basin, chlorine isotope, ancient salt rock, ancient sylvinite deposit, deposit stage

Spectral analysis of quasi-stationary sea surface topography from GRACE mission

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Science china Earth {1. 2005年第11期48卷 2040-2048页

作者： ZHANG Zizhan1.2.& LU Yang1.3 1. Institute of Geodesy and Geophysics, {1. Academy of sciences, Wuhan 430077,{2. 2. graduate school of the {1. Academy of sciences, beijing 1.0039,{2. 3. Unite Center for Astro-geodymics Research, {1. Academy of sciences, Shanghai 2.0030,{2. 1. Institute of Geodesy and Geophysics Chinese Academy of Sciences 430077 Wuhan China 2. {1. school of the {2. Academy of sciences 100039 Beijing China 3. Unite Center for Astro-geodymics Research Chinese Academy of Sciences 200030 Shanghai China

During the last two decades satellite altimetry has offered an abundance of meas-urements of the sea surface resulting in the improvement of global mean sea surface height (MSSH) and marine geoid determination. On the other hand, with the launching of new genera-tion gravity satellites, some high accuracy long-wavelength gravity models are available. These breakthroughs give us a great opportunity for new estimation of quasi-stationary sea surface topography (QSST). In this paper, the new gravity model GGM01. derived from GRACE mission is briefly presented, and a new global high precision and high-resolution QSST is determined based on the GGM01. model and the global MSSH. The spectral features of the QSST esti-mated by GGM01. and EGM96 gravity model to degree/order 2.0 are discussed by spectral analysis. As a result, the QSST is mainly composed of long waves, medium waves partially and short waves scarcely, its power spectral structures are different between the zonal direction and the meridional direction, there are great differences between the two models, which maybe ex-plain why the ocean currents derived from the two gravity models by Tapley show different pat-terns.

关键词： quasi-stationary sea surface topography, mean sea surface height, GGM01. fast Fourier transform, spectral analysis

Kinetics and reaction mechanism of phenol hydroxylation catalyzed by La-Cu_4FeAlCO_3

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Science china Chemistry 2005年第6期48卷 530-537页

作者： CHEN Chunxia1.2. XU Chenghua1. FENG Liangrong1. SUO Jishuan1.& QIU Fali1.1. Chengdu Institute of Organic Chemistry, {1. Academy of sciences, Chengdu 61.041.{2. 2. graduate school of the {1. Academy of sciences, beijing 1.0039,{2. 1. Chengdu Institute of Organic Chemistry Chinese Academy of Sciences 610041 Chengdu China 2. {1. school of the {2. Academy of sciences 100039 Beijing China

The present work synthesizes La-Cu4FeAlCO3 catalyst under microwave irradiation and characterizes its structure using XRD and IR techniques. The results show that the obtained La-Cu4FeAlCO3 has a hydrotalcite structure. In the phenol hydroxylation with H2.2.catalyzed by La-Cu4FeAlCO3, the effects of reaction time and phenol/H2.2.molar ratio on the phenol hy-droxylation, and relationships between the initial hydroxylation rate with concentration of the catalyst, phenol, H2.2.and reaction temperature are also investigated in details. It is shown the phenol conversion can reach 50.09% (mol percent) in the phenol hydroxylation catalyzed by La-Cu4FeAlCO3, under the reaction conditions of the molar ratio of phenol/H2.2.1.2. the amount ratio of phenol/catalyst 2., reaction temperature 343 K, reaction time 1.0} min, 1. mL distilled water as solvent. Moreover, a kinetic equation of v = k[La ? Cu 4 FeAlCO 3 ][C 6 H 5 OH][H 2.O 2.. and the activation energy of Ea=58.37 kJ/mol are obtained according to the kinetic studies. Due to the fact that the HO-Cu+-OH species are detected in La-Cu4FeAlCO3/H2.2.system by XPS, the new mechanism about the generation of hydroxyl free radicals in the phenol hydroxylation is pro-posed, which is supposed that HO-Cu+-OH species are transition state in this reaction.

关键词： rare earth, hydrotalcite, microwave irradiation, phenol hydroxylation, kinetics, reaction mechanism.

The deep thermal characteristic of continental margin of the northern South china Sea

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chinese Science Bulletin 2000年第18期45卷 1717-1722页

作者： ZHANG Jian & WANG Jiyang1. graduate school, University of Science and Technology of{2., chinese Academy of sciences, beijing 1.0039,{2. 2. Institute of Geology, chinese Academy of sciences, beijing 10002.,{2. graduate {1. University of Science and Technology of China Chinese Academy of Sciences Beijing China Institute of Geology Chinese Academy of Sciences Beijing China

Heat flow plays an important role in the study ot thermal structure and thermal evolutionof continental margin of the northern South china Sea. The analysis of heat flow value shows that margin heat flow in the northern South china Sea is relatively high setting, but the percentage of crustal heat flow is lower than 35% in terrestrial heat flow. The terrestrial heat flow exhibited a current of rise from the Northern Continental Margin to the Southern Central Basin. However, the proportion of crustal heat flow in terrestrial heat flow slowly dropped down in the same direction. It is suggested that the main factor causing high heat flow setting is the moving up of hot material from asthenosphere.

关键词： margin of northern South china Sea terrestrial heat flow thermal structures.