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The characteristics of chert from micro-disseminated gold deposits and their origin significance in southwestern Guizhou, china

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chinese Science Bulletin 1999年第S2期44卷 20-21页

作者： LIU Jiajun~1, LIU Congqiang~1, LIU Jianming~2.and GU Tuan~1 1. Institute of Geochemistry, chinese academy of Sciences, Guiyang 550002. {2. 2. The reseatrch center of mineral Resources exploration, chinese academy of Sciences, beijing 1.01.1. china Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China Research center of {1. Resources {2. Chinese Academy of Sciences Beijing 100101 China

THE southwestern Guizhou Province has been acknowledged as one of the most important and potentialgold producing areas in the People’ s Republic of china and has attracted world-wide attention since thediscovery of a series of sediment-hosted micro-disseminated gold deposits in the last twenty years. Chertwidely occurs in the gold deposits. Study on geology and geochemistry of the chert may be important for abetter understanding of the forming condition and process of gold. 1.Characteristics of chert THE cherts are characterized by bedded, massived, pseudobrecciated and nodular structures, occurring insynsedimentary fault. The thickness of a chert bed generally varies from several meters to less than {1.meters, with the maximum up to about 70 meters. Host elements are simple and concentrated in thecherts. The SiO{1./sub> concentration of the cherts varies from 86.4 % to 95.64 %, 91.95% on average

关键词： chert micro-disseminated gold deposits Guizhou.

Nonlinear interactions between gravity waves and background winds

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Progress in Natural Science:Materials International 2007年第6期17卷 639-644页

作者： Liu Xiao1.2.and Xu Jiyao1.1. State Key Laboratory for Space Weather, {1. for Space Science and Applied Research, chinese {2. of Sciences, beijing 1.0080, china 2. Graduate University of chinese {2. of Sciences, beijing 1.0039, china) [a]State Key Laboratory for Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China [b]Graduate University of chinese {1. of Sciences Beijing China

Using the nonlinear propagating gravity waves (GW) model in the two-dimensional compressible atmosphere and the linear GW theory, the process of GW propagation in different background winds, e.g. the direction of the background wind is opposite to (dead wind) or the same as (tail wind) the direction of the horizontal phase velocity of GW, is studied. The results show that the dead wind prolongs the vertical wavelength and accelerates GW propagation. Therefore, GW propagates up to a higher height becomes instable in a short time and eventually induces an inverse jet flow. Then, the vertical wavelength is becoming short due to the nonlinear interactions between GW and the inverse jet flow. The vertical wavelength and group velocity decrease after GW propagates into the tail wind. The initial instable time is delayed. Although most of GW is trapped in the instable region, some of GW propagates above the instable region. Compared with GW propagation in the tail wind, the nonlinear interactions between GW and the dead wind are also strong. In contrast, the linear GW theory predicts that GW can propagate freely in the dead wind. The vertical wavelength simulated by the nonlinear numerical model is different from that predicted by the linear theory greatly after GW propagates into the dead wind.

关键词： gravity waves background winds vertical group velocity vertical wavelength nonlinear interactions.

Study of thin cloud removal method for CBERS-02.image

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Science china(Technological Sciences) 2005年第S2期48卷 91-99页

作者： MA Jianwen1. GU Xingfa1. FENG Chun2.& GUO Jianning2.1. Institute of Remote Sensing Application, chinese academy of Sciences,{2. 2. china center for Resource Satellite Data and Applications, beijing 1.0073, china 1. Institute of Remote Sensing Application Chinese Academy of Sciences 100101 Beijing China 2. {1. center for Resource Satellite Data and Applications 100073 Beijing China

The china Brazil Earth Resources Satellite (CBERS) ended the dependence on foreign satellites. Along with the series of CBERS and the enhancement of satellite applications, it is necessary to search correlative data processing methods. Because cloud appears in the atmosphere, an image with clear sky conditions is often hard to obtain. How to remove cloud is an important sector of increasing image quality. An improved homomorphism filtering method is adopted to remove thin cloud qualitatively at first, and all bands are selected to classify pixels. Based on the fact that visible band images contain more aerosol effects than infrared bands, visible bands are used to determine clear or hazy regions and the reflectances of different surface classes in clear regions are calculated. At last the mean reflectance of the same classes in clear and hazy regions is matched to remove cloud. The image visual effect is improved; meanwhile, the ground reflectance is retrieved to meet the needs of remote sensing quantification.

关键词： CBERS-02 cloud removal surface reflectance mean reflectance matching.

Preparation and characterization of a novel adsorbent for removing lipophilic organic from water

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Science china Chemistry 2005年第6期48卷 600-604页

作者： LIU Huijuan1. DAI Ruihua1. QU Jiuhui1.& RU Jia1.2.1. State Key Laboratory of Environmental Aquatic Chemistry, Research {1. for Eco-Environmental Sciences, chinese {2. of Sciences, beijing 1.0085, china 2. Graduate School of the chinese {2. of Sciences, beijing 1.0039, china 1. State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences 100085 Beijing China 2. Graduate School of the {1. academy of Sciences 100039 Beijing China

A novel composite adsorbent containing a kind of lipid-triolein is studied. The ad-sorbent is prepared by embedding triolein into cellulose acetate (CA) sphere. The preparation method, the physical-chemical properties of the adsorbent and the removal efficiency of two or-ganochlorinated pesticides are studied. The adsorbent is stable in water and no triolein leaks into water for 465 h soaking. The adsorbent has high adsorption capacity for organochlorinated pes-ticides such as dieldrin and aldrin. The results suggest that triolein-containing adsorbent could serve as a good adsorbent for lipophilic organic pollutants. The adsorption rate for lipophilic pol-lutants is very fast and has relation with the logKow of the compounds.

关键词： triolein, cellulose acetate, adsorbent, lipophilic organic, drinking water.

Interannual variability of Antarctic Oscillation and its influence on East Asian climate during boreal winter and spring

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Science china Earth Sciences 2006年第5期49卷 554-560页

作者： FAN Ke1.2.3 & WANG Huijun2.1. Nansen-Zhu International Research center, Institute of Atmospheric Physics, chinese {2. of Sciences, beijing 1.002., china 2. Department of Atmospheric Science, Yunnan University, Kunming 650091. china 3. Graduate University of the chinese {2. of Sciences, beijing 1.0049, china 1. Nansen-Zhu International Research center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Department of Atmospheric Science Yunnan University Kunming 650091 China 3. Graduate University of the chinese {1. of Sciences Beijing 100049 China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific Ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.

Compression behavior of Zr_(41.Ti_(1.)Cu_(1.0}5)Ni_(1.)Be_(2..5) bulk metallic glass up to 2. GPa

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Science china(Physics,Mechanics & Astronomy) 2005年第3期48卷 319-324页

作者： LI Gong 1, 2., ZHAN Zaiji 2., LIU Jing 3 , YUN Jinku 1 , SUN Liling 2., LIU Riping 1 , ZHANG Jun 2.& WANG Wenkui 1, 2.1. Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, china 2. center for Condensed Matter Physics, Institute of Physics, {2. academy of Sciences, beijing 100080, china 3. BSRF, Institute of High Energy Physics, {2. academy of Sciences, beijing 100039, china 1. Key Laboratory of Metastable Materials Science and Technology Yanshan University 066004 Qinhuangdao China 2. {1. for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences 100080 Beijing China 3. BSRF Institute of High Energy Physics Chinese Academy of Sciences 100039 Beijing China

The compression of a Zr41.i1.Cu1.0}5Ni1.Be2..5 bulk metallic glass (BMG) is investigated at room temperature up to 2. GPa using in-situ high pressure energy dispersive X-ray diffraction with a synchrotron radiation source. The pressure-induced structural relaxation is exhibited. It is found that below about 8 GPa, the existence of excess free volume contributes to the rapid structural relaxation, which gives rise to the rapid volumetric change, and the structural relaxation results in the structural stiffness under higher pressure.

关键词： bulk metallic glass, high pressure, structural relaxation, synchrotron radiation.

Dipole anomaly in the Arctic atmosphere and winter Arctic sea ice motion

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Science china Earth Sciences 2005年第9期48卷 1529-1536页

作者： WU Bingyi1. ZHANG Renhe1.& WANG Jia2.1. {1. academy of Meteorological Sciences, {2. 1.0081. china 2. International Arctic Research center, University of Alaska Fairbanks, AK 99775, USA 1. chinese {1. of Meteorological Sciences 100081 Beijing China 2. International Arctic Research {1. University of Alaska Fairbanks 99775 AK USA

This paper investigates a previously-ignored atmospheric circulation anomaly-di- pole structure anomaly in the arctic atmosphere, and its relationship with the winter sea ice mo- tion, based on analyses of the International Arctic Buoy Programme Data (1.79―1.98) and datasets from the National center for Environmental Prediction (NCEP) and the National center for Atmospheric Research (NCAR) for the period of 1.60―2.02. The dipole structure anomaly is the second-leading mode of EOF of monthly mean SLP north of 70°N during the winter season (Oct.―Mar.), which accounts for 1.% of the variance. One of its two anomaly centers is over the Canadian Archipelago; the other is situated over northern Eurasia and the Siberian marginal seas. Due to the dipole structure anomaly’s strong meridionality, it becomes an important mechanism to drive both anomalous sea ice export out of the Arctic Basin and cold air outbreaks into the Barents Sea, the Nordic Seas and northern Europe.

关键词： dipole anomaly, winter season, Arctic, sea ice motion, sea ice export.

Photogeneration of the free radicals and singlet oxygen by chrysophanol from rheum

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Science china Chemistry 2004年第5期47卷 381-387页

作者： RAO Jing1.2. XIE Jie1. ZHAO Jingquan1.& ZHU Teng2.1. Key Laboratory of Photochemistry, center for Molecular Science, Institute of Chemistry, The chinese {2. of Sciences, beijing 1.0080, china 2. University of Science and Technology beijing, beijing 1.083, china 1. Key Laboratory of Photochemistry Center for Molecular Science Institute of Chemistry The Chinese Academy of Sciences 100080 Beijing China 2. University of Science and Technology {1. 10083 Beijing China

In the current work, chryosphanol (MHAQ) was isolated and purified from rheum, and the photosensitization activities were studied. In nitrogen-saturated DMSO solution, irradia- tion of chryosphanol (MHAQ) with visible light (>430 nm) produced the semiquinone radical anions (MHAQ??), which was intensified significantly by an electron donor NADH, suggesting electron transfer between the excited and ground state photosensitizer molecules. In an air-saturated DMSO solution, superoxide radical anions (O2.), trapped by DMPO, were detected. ?? It was proved that O2.was not originated from the singlet oxygen (1.2. but dependent on DMPO, ?? chrysophanol, oxygen and the irradiation time. The singlet oxygen and OH could also be pro- ? duced by the photosensitization of the photosensitizer. These suggest that chrysophanol pos- sesses the photosensitization activity via Type I mechanism and Type II mechanism. To evaluate the photosensitization activities of MHAQ, emodin and mixed anthraquinone derivatives ex- tracted from rheum, the relative productivities of O2.were estimated to be 1.8, 1.1.and 1.0 re- ?? spectively and the quantum yields for singlet oxygen to be 0.36, 0.53 and 0.1. respectively. Therefore, these low-cost pigments may be potentially used as phototherapeutic medicine for some kind of vascular diseases or photo-activated pesticides.

关键词： chrysophanol, ESR, semiquinone radical anions, superoxide radical anions, hydroxyl radical, singlet oxygen.

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

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Science china Earth Sciences 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. Graduate School of the {1. 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