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chinese Science Bulletin 2005年第24期50卷 2866-2871页

作者： WANG Ninglian Key Laboratory of Cryosphere and environment, Cold and Arid Regions environmental and Engineering research institute, chinese academy of Sciences, Lanzhou 73000, china institute of Tibetan Plateau research, chinese academy of Sciences, beijing 100085, china Key Laboratory of Cryosphere and environment Cold and And Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 73000 China Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China

By analyses of the dust layers in the Malan ice core from the northern Tibetan Plateau, it was found that dirty ratio in this core might be a good proxy for dust event frequency. The variations in the dirty ratio displayed a de- crease trend over the past 200 years, which implies that dust events became less frequent during the study period. The decrease trend in the variations in dust event frequency might be caused mostly by the natural processes, including increasing precipitation and weakening westerly which might be related with global warming. Furthermore, significant negative correlation was found between the dirty ratio and δ 18O in the Malan ice core. This is highly important for studying the effect of atmospheric dust on climate change.

关键词：青藏高原马伦冰核气候变化扬尘事件发生频率

Rheological behaviour of semi-solid succinonitrile-camphor alloy

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Journal of University of Science and Technology beijing 2003年第1期10卷 25-29页

作者： Zhenyao WangState Key Laboratory for Corrosion and protection, institute of Metal research, chinese academy of Sciences, Shenyang 110016, china Lab. for Corrosion and protection Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China

Rheology experiments were carried out on succinonitrile-4% (mass fraction) camphor alloy, using a Haake VT550 viscometer. The results showed that the steady state viscosity of succinonitrile-4% camphor alloy in semi-solid process can be described well by the classical power law of viscosity versus shear rate, η= kγm, and the test method can be used to simulate the semi-solid processing for metals. The viscosity of the organic alloy decreases with increasing shear rate at a given temperature within liquid-solid range, and the viscosity of the organic alloy slurries increases with decreasing temperature, decreases with decreasing cooling rate. The structure and viscosity of organic alloy during solidification are strongly influenced by shear rate.

关键词： rheology semi-solid processing viscosity organic alloy microstructure

Modeling diameter distribution of the broadleaved-Korean pine mixed forest on Changbai Mountains of china

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Science china(Technological Sciences) 2006年第z1期49卷 177-188页

作者： WANG Shunzhong, DAI Limin, LIU Guohua, YUAN Jianqiong, ZHANG Hengmin & WANG Qingli institute of Applied ecology, chinese academy of Sciences, Shenyang 110016, china Graduate University of chinese academy of Sciences, beijing 100039, china State Key Lab of Systems ecology, research Center for Eco-environmental Sciences, chinese academy of Sciences, beijing 100085, china institute of Applied ecology Chinese Academy of Sciences Shenyang 110016 China Graduate University of chinese academy of Sciences Beijing 100039 China State Key Lab of Systems ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

The broadleaved-Korean pine mixed forest is a native vegetation in the Changbai Mountains, northeast china. The probability density functions including the normal, negative exponential, Weibull and finite mixture distribution, were used to describe the diameter distributions of the species groups and entire forest stand. There is a strong correlation between parameters and mean DBH except the shape parameters in the mixture distribution. The diameter classes of species and entire forest stand showed not negative exponential but normal and "S" distribution. The mixture function was better than normal and Weibull to describe the model distribution. The location parameter had an effect on the estimated frequency in the first diameter class, when the estimated location parameter was bigger than the lower limit of the first diameter class.

关键词： broadleaved-Korean pine mixed forest, diameter distribution, finite mixture distribution.

Relationship between environmental Pollution of Coal Mine and Spectral Characteristics of Nearby Plants

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Journal of University of Science and Technology beijing 2001年第1期8卷 10-14页

作者： Liqing Lei institute of Geographic Sciences and Natural Resources research, chinese academy of Sciences, beijing 100101, china chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China

Remote sensing technology, as the most advanced method for collecting data, along with the common ways often used in the past on research of environmental science, was integrated to study the relationship between environmental pollution of coal mine and spectral characteristics of nearby plants. With compositive index and mean reflectivity at near infrared, a regression equation was established, and a conclusion was made that spectral reflectivity can be used to distinguish regions with different pollution degree. Through testing with real status of the research region, it is verified that this kind of integration and conclusion not only are helpful for human being in controlling the movement law of pollutants and the corresponding change of coal mine environmental quality but also bring a new way for the research of environment problems of coal mine.

关键词： remote sensing spectral characteristics reflectivity pollution index compositive index atmospheric pollution

Construction and evaluation of a novel end-column amperometric detection system for electrophoresis microchips

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Science china Chemistry 2010年第1期53卷 250-256页

作者： CHEN ZhiFeng1,GAO YunHua2,WANG Li3,CHU XiaoGang1 1chinese academy of Inspection and Quarantine,beijing 10012.,china 2Technical institute of Physics and Chemistry,chinese academy of Sciences,beijing 100190,china 3beijing institute of Labour protection,beijing 100054,china 1. chinese academy of Inspection and Quarantine Beijing 100123 China2. Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100190 China3. Beijing Institute of Labour Protection Beijing 100054 China

A set of integrated end-column amperometric detection system has been developed,onto which an electrophoresis microchip can be conveniently *** machined by a piece of transparent organic glass,the system consists of an electrophoresis microchip platform and an amperometric detection reservoir,in which the microchip can be fixed onto the platform by microchip grooves and with stainless steel *** detection electrode can be directly fixed in the amperometric detection reservoir by screws and *** dopamine as the model analyte,we take platinum disc electrodes with different diameters of 100 μm,300 μm and 500 μm and a carbon fiber electrode with the diameter of 240 μm as the working electrode,all of which accomplish sensitive *** detection parameters of the system are optimized with the carbon fiber *** detection results show that in the electrochemical cleaning procedure,the relative deviations of 3.2% and 0.5% for the peak current and retention time,respectively,can be obtained for the successive detections of 100 μM dopamine,and the limit of detection for dopamine can reach 0.4 μM(S/N = 3).This system is small,but its performance of detection is stable and sensitive,and the replacement of its working electrodes is convenient,so it is very suitable as a universal platform of end-column amperometric detection for electrophoresis microchips.

关键词： electrophoresis microchip amperometric detection dopamine evaluation

research on TemporaI and Spatial Patterns and Dynamic Laws of Soil Water at Eco-tope between Oasis and Desert

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chinese forestry Science and Technology 2002年第2期1卷 31-37页

作者： WANG Bing CUI Xianghui BAO YonghongThe research institute of forest ecology. environment and protection chinese academy of forestry. beijing 100091, china

Based on long term and stationary research, the temporal and spatial patterns and dynamic laws of soil water content in Minqin desert area were studied. Some results are as follows:(1)The change of soil water content in different years is not obviously in shrub sand dune of Nitraria sibirica and Tamarix ramosissima, but it was great in shifting sand dune, the maximum is 2.538%; (2)The season dynamics can be divided into three stages: accumulating, consuming and stable; (3) The vertical change of soil wa...

关键词： Minqin desertification soil water content temporal and spatial pattems dynamic laws

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 Sciences 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 259 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)

Relationships between tree-ring width index and NDVI of grassland in Delingha

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chinese Science Bulletin 2006年第9期51卷 1106-1114页

作者： HE Jicheng1,3 & SHAO Xuemei1,21. institute of Geographical Sciences and Natural Resources research, chinese academy of Sciences, beijing 100101, china 2. institute of Tibetan Plateau research, chinese academy of Sciences, beijing 100085, china 3. Graduate School of chinese academy of Sciences, beijing 100039, china institute of Geographical Sciences and Natural Resources research Chinese Academy of Sciences Beijing China Graduate School of chinese academy of Sciences Beijing China institute of Tibetan Plateau research Chinese Academy of Sciences Beijing China

Using five well-replicated Qilian juniper (Sabina przewalskii Kom.) tree-ring width index se- ries, monthly normalized difference vegetation index (NDVI) of grassland, and climatic data from 1982 to 2001, the relationships between tree-ring width index, NDVI of grassland, and climatic data were analyzed firstly. Then, the relationship between tree-ring width index and NDVI of grassland was explored. The re- sults showed that: (1) Temperature and precipitation in June influenced tree-ring width index and NDVI of grassland deeply in Delingha. (2) There were sig- nificant relationships between five tree-ring width index series (DLH1-DLH5) and monthly NDVI of grassland from June to September, with the most significant relationship being between tree-ring width index series and NDVI of grassland in August. (3) The PC1 (the first principal component derived from DLH1-DLH5 series) exhibited good agreement with monthly NDVI of grassland in the grass growth sea- son (from June to September) and the averaged NDVI in the growth season, which was attributed to their common responses to water-supply limit in Delingha. This study may allow an increase in studying the past dynamics of grassland in Delingha in that the variation of grassland NDVI during the last millennium has been reconstructed from PC1.

关键词：圆柏祁连山 NDVI 草原年轮宽度指数

Study on forest Fire Occurrence in china

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chinese forestry Science and Technology 2002年第3期1卷 59-64页

作者： SHU Lifu TIAN Xiaoruiresearch institute of forest ecology, environment and protection. chinese academy of forestry. beijing 100091, china,

china is not rich in natural forest sources. Owing to natural and historical factors, forest fires have long been frequenting china. forest fire prevention is the most important of all. forest fire prevention and controlling have long been held as a very important factor in our ecological plans. Taking china 's special geographical location, topography, climate and the distribution of forest sources into consideration, we have every reason to believe that forest fires in china have their own special env...

关键词： forest Fire Fire environment Fire Occurrence

Chronology of Holocene lacustrine sediments in Co Ngoin, central Tibetan Plateau

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Science china Earth Sciences 2006年第9期49卷 991-1001页

作者： WU Yanhong1, WANG Sumin1& HOU Xinhua1,3 1. Key Laboratory of Lake Sedimentation and environment, Nanjing institute of Geography and Limnology, chinese academy of Sciences, Nanjing 210008, china 2. institute of Tibetan Plateau research, chinese academy of Sciences, beijing 10085, china 3. Graduate University of chinese academy of Sciences, beijing 100039, china 1. Key Laboratory of Lake Sedimentation and environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China 2. institute of Tibetan Plateau research Chinese Academy of Sciences Beijing 10085 China 3. Graduate University of chinese academy of Sciences Beijing 100039 China

Chronology is the basis for using lacustrine sediments to reconstruct the history of en-vironmental change. Radioactive-nuclides such as 14C, 210Pb and 137Cs dating are mainly used to establish the chronology for recent several ten thousand years. Because of being mixed with “dead carbon”, the measured 14C age is always older than the actual age which is recognized as “reservoir effect”. Cs is a kind of active metal element, and easy to migrate vertically in the sediment that leads to the error of the time marker. 210Pb dating should make sure to select CIC model or CRS model. On the Tibetan Plateau, most of the lakes are alkaline closed lake where Cs is more moveable in the sediment and the reservoir effect caused by “dead carbon” on 14C dating is stronger. Based on the analysis on results of 14C, 210Pb and 137Cs of the lacustrine sediments from Co Ngoin, central Tibetan Plateau, we use the simple regression method to re-calculate the 14C calendar ages, and establish the time sequence for cores CE-1 and CE-2 with result of 210Pb CRS model for the upper 35 cm and re-calculated 14C calendar age for sediments bellow 35 cm. Since 1400 cal. a BP, sedimentation inter-rupted for more than 1000 years. According to this time sequence, variations of environmental proxies confidently reflect the major climatic events in Holocene.

关键词： 14C, 210Pb and 137Cs, chronology, lacustrine sediments, climatic event, Co Ngoin, central Tibetan Plateau.