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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, China 2. Graduate School of the chinese academy of sciences, Beijing 100039, China 1. Key Laboratory of Excited State Physics Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences 130033 Changchun China 2. Graduate School of the chinese 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.

Current status and future of acid rain in China

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chinese Science Bulletin 1997年第24期42卷 2076-2081页

作者： DING Guo’an, XU Xiaobing, FANG Xiumei, JIN Shaping, XU Xia, Tang Jie, LIU Qijun, WANG Shufeng and WANG Wenxing1. chinese academy of Meteorological {2., Beijing 100081, China 2. chinese academy of Environment {2., Beijing 100012. China chinese academy of Meteorological {2. Beijing 100081 China

As a part of the national key project of acid rain research, chemical element analysis of rainwater has been carried out based on observation of acid rain network in chinese MeteorologicalAdministration over the years of 1992.and 1993. Samples of precipitation collected from eachacid rain station were taken according to the standard established by chinese MeteorologicalAdministration. pH value was measured with pH meter (accuracy of 0. 01) made in

关键词： acid rain current status future.

Environmental characteristics of Mid-Holocene recorded by lacustrine sediments from Lake Daihai, north environment sensitive zone, China

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Science China Earth sciences 2006年第9期49卷 968-981页

作者： SUN Qianli1,2. ZHOU Jie1, SHEN Ji3, CHEN Peng1,2. WU Feng1,2.& XIE Xiuping1,2.1. State Key Lab of Loess and Quaternary Geology, Institute of Earth Environment, chinese academy of sciences, Xi’an 710075, China 2. Graduate University of chinese academy of sciences, Beijing 100039, China 3. Nanjing Institute of Geography and Limnology, chinese academy of sciences, Nanjing 2.0008, China 1. State Key Lab of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 2. Graduate University of chinese academy of sciences Beijing 100039 China 3. Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China

Climate proxies, such as total organic carbon and nitrogen (TOC, TN), carbonate content (CaCO3), grain-size and pollen of the sediment core retrieved from enclosed Lake Daihai which lies in the north China environment sensitive zone are analyzed to reconstruct the environment evolution of the area based on high-resolution radiocarbon chronology. The results reveal that the TOC and TN contents of the sediments correlate well with pollen percentage and pollen flux variations during the Holocene, and both reach their peak values simultaneously at 6.7―3.5 ka BP (calendar age, 7.6―3.6 ka BP). Since 6.7 ka BP, both the CaCO3 and organic matter contents of the core have simultaneous variations, and their high values also occur during 6.7―3.5 ka BP. While during 9.0―6.7 ka BP (calendar age, 10―7.6 ka BP) relatively lower level of organic matter content and pollen flux corre- spond to the higher level of carbonate content. The above relations suggest that during 6.7―3.5 ka BP, the productivity and effective precipitation were greatly improved in the lake drainage area, and this would probably strengthen the hydrodynamic conditions, enhancing organic matter, pollen and carbonate inputs from terrestrial sources. Such processes would account for the enrichment of both organic matter and carbonate in the sediments. While during 9.0―6.7 ka BP, the lower level of or- ganic matter, pollen flux but high carbonate content show depressed productivity and declined vege- tation coverage. The higher carbonate content at this stage would have probably resulted from the higher evaporation ratio of the lake water under relatively drier climate conditions. Therefore, it is in- ferred that during 6.7―3.5 ka BP, the climate was more humid with abundant rainfalls and vegetation was more flourishing in the Lake Daihai area. This can be seen as Holocene Climate Optimum (HCO). As a result, this has evident discrepancies with the traditional notion that the HCO occurs at Early Holocene or early Mid

关键词： Lake Daihai, Mid-Holocene, lacustrine sediments, environmental characteristics.

Debris Flow Hazard Assessment Based on Support Vector Machine

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wuhan University Journal of Natural sciences 2006年第4期11卷 897-900页

作者： YUAN Lifeng 1, 2., ZHANG Youshui 3 1. Institute of Mountain Hazards and Environment, chinese academy of sciences, Chengdu 610041, Sichuan, China 2. Graduate University of chinese academy of sciences, Beijing 100049, China 3. Institute of Geographical {2. and Natural Resources Research, chinese academy of sciences, Beijing 100101, China Institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China Graduate University of chinese academy of sciences 100049 Beijing China Institute of Geographical sciences Natural Resources Research Chinese Academy of Sciences 100101 Beijing China

Seven factors, including the maximum volume of once flow , occurrence frequency of debris flow , watershed area , main channel length , watershed relative height difference , valley incision density and the length ratio of sediment supplement are chosen as evaluation factors of debris flow hazard degree. Using support vector machine （SVM） theory, we selected 2.9 basic data of 37 debris flow channels in Yunnan Province as learning samples in this study. We create a debris flow hazard assessment model based on SVM. The model was validated though instance applications and showed encouraging results.

关键词： debris flow hazard assessment support vector machine (SVM)

Influence of the earth rotation on the interfacial wave solutions and wave-induced tangential stress in a two-layer fluid system

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Acta Oceanologica Sinica 2009年第2期28卷 115-120页

作者： SONG Jinbao LIU Yongjun Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Key Laboratory of Ocean Circulation and Waves （KLOCAW） Chinese Academy of Sciences Qingdao 266071 China Graduate University of chinese academy of sciences Beijing 100039 China

Interfacial waves and wave-induced tangential stress are studied for geostrophic small amplitude waves of two-layer fluid with a top free surface and a fiat bottom. The solutions were deduced from the general form of linear fluid dynamic equations of two-layer fluid under the f-plane approximation, and wave-induced tangential stress were estimated based on the solutions obtained. As expected, the solutions derived from the present work include as special cases those obtained by Sun et al. （2.04. Science in China, Ser. D, 47（12.： 1147-1154） for geostrophic small amplitude surface wave solutions and wave-induced tangential stress if the density of the upper layer is much smaller than that of the lower layer. The results show that the interface and the surface will oscillate synchronously, and the influence of the earth＇s rotation both on the surface wave solutions and the interfacial wave solutions should be considered.

关键词： two-layer fluid interfacial waves wave-induced tangential stress earth rotation

High-temperature phases of pyrophyllite and their evolutionary characteristics

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chinese Science Bulletin 1997年第2期42卷 140-144页

作者： WANG Ling and ZHANG Zhenyu1. Changsha Institute of Geotectonics, chinese academy of sciences, Changsha 410013, China 2. Institute of Geology, chinese academy of sciences, Beijing 10002., China Changsha Institute of Ceotectonics Chinese Academy of Sciences Changsha China Institute of Geology Chinese Academy of Sciences Beijing China

WITH the increase of heating temperature, phase of pyrophyllite will undergo a series of transformations. Former scholars have done some work in this respect; the temperature spans,however, were normally not more than 1150℃ and no relatively comprehensive results have been reported. Thus, the features of the phases from indoor temperature to melting point (1710℃±) for pyrophyllite and the entire evolutionary process of the phases are uncertain.

关键词： pyrophyllite high-temperature phase phase tranformation pyrophyllite anhydrite mullite cristobalite.

“Double dawn”eclipse and the rotational variation of the earth

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chinese Science Bulletin 2000年第11期45卷 988-991页

作者： ZHANG Peiyu & HAN Yanben1. Purple Mountain Observatory, chinese academy of sciences, Nanjing 2.0008, China 2. Beijing Astronomical Observatory, chinese academy of sciences, Beijing 100012. National Astronomical Observatory, chinese academy of sciences, Beijing 100012. China Purple Mountain Observatory Chinese Academy of Sciences Nanjing China Beijing Astronomical Observatory Chinese Academy of Sciences Beijing National Astronomical Observatory Chinese Academy of Sciences Beijing China

A record of 'double dawn' at State Zheng in the first year of the reign of King Yi in Western Zhou Dynasty in the chronicle 'Bamboo Annals' (Zhushu Jinian) is discussed. We think that it may be a record of an annular solar eclipse happening in 899 BC. The record and the AT, which describes the secular variation of the earth’s rotation, are analyzed and discussed.

关键词： solar eclipse earth’s rotation.

PCDD／Fs in sodium pentachlorophenate（Na－PCP） and human blood， milk and sediment samples from chinese schistosomiasis areas

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Journal of Environmental sciences 1995年第1期7卷 52-59页

作者： Jiang Ke Chen Yudong Li Lingjun(Research Center for Eco-Environmental sciences,chinese {2. of sciences,Beijing 100085,China)

ＰＣＤＤ／Ｆｓｉｎｓｏｄｉｕｍｐｅｎｔａｃｈｌｏｒｏｐｈｅｎａｔｅ（Ｎａ－ＰＣＰ）ａｎｄｈｕｍａｎｂｌｏｏｄ，ｍｉｌｋａｎｄｓｅｄｉｍｅｎｔｓａｍｐｌｅｓｆｒｏｍＣｈｉｎｅｓｅｓｃｈｉｓｔｏｓｏｍｉａｓｉｓａｒｅａｓ... 详细信息

ＰＣＤＤ／Ｆｓｉｎｓｏｄｉｕｍｐｅｎｔａｃｈｌｏｒｏｐｈｅｎａｔｅ（Ｎａ－ＰＣＰ）ａｎｄｈｕｍａｎｂｌｏｏｄ，ｍｉｌｋａｎｄｓｅｄｉｍｅｎｔｓａｍｐｌｅｓｆｒｏｍＣｈｉｎｅｓｅｓｃｈｉｓｔｏｓｏｍｉａｓｉｓａｒｅａｓＪｉａｎｇＫｅ；ＣｈｅｎＹｕｄｏｎ...

关键词： sodium pentacuorophenate PCDD/Fs molluscacde.

Properties and applications of cold supersonic gas jet

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Science China(Physics,Mechanics & Astronomy) 2006年第6期49卷 709-715页

作者： ZHANG Shaofeng1,2.MA Xinwen1,2.LIU Huiping2.LI Bin1,2.& ZHU Xiaolong1,2.1. Institute of Modern Physics,chinese academy of {2.,Lanzhou 730000,China 2. Graduate University of chinese academy of sciences,Beijing 100049,China 1. Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China 2. Graduate University of chinese academy of sciences Beijing 100049 China

By analyzing the formation mechanism of a supersonic gas jet,a set of equations which describe the atomic beam properties were established. The influence of initial temperature,initial pressure,background gas pressure and pumping speed was discussed in detail. A simulation program was developed based on the equations,and the results under different initial conditions were obtained. The results are in good agreement with the experimental data,and suggest that,in order to get much smaller transverse momentum in collision experiments,it is necessary to lower the initial temperature and the initial pressure of the supersonic gas jet,together with increasing the pumping speed. These results are very instructive for construction of a new generation of cold supersonic gas jets.

关键词： cold supersonic gas jet,zone of silence,nozzle,skimmer.