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Identification of the Angel -related elements in cyprinid fishes and their phylogenetic implications

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Progress in Natural science:Materials International 2007年第2期17卷 168-171页

作者： WANG Li, HE shunping and CHEN Yiyu ( Institute of Hydrobiology, Chinese Academy of sciences, Wuhan 430072, China graduate school of the Chinese Academy of sciences, beijing 100039, China National Natural science Foundation of China, beijing 100085, China) Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China. graduate school of Chinese Academy of sciences Beijing 100039 China. National Natural science Foundation of China Beijing 100085 China

Angel-related element belongs to the family of miniature inverted-repeat transposable elements (MITEs). In this paper we report the identification of an Angel- related element in the series Leuciscini of cyprinid fishes, which is located in the second intron of the growth hormone (GH) gene. We have also found that this element is absent in orthologous locus in the series Barbini of cyprinid fishes, that provides new evidence for the monophyly of the series Leuciscini. The insertion of Angel -related element into the GH gene might take place in the common ancestor of the series Leuciscini after its divergence from the series Barbini. The high sequence divergence and relatively broad species distribution of Angel-related elements implies that they might be ancient transposons which appeared about 26 million years ago.

关键词： Angel -related elements the series Leuciscini monophyly.

Effect of concentration on surfactant micelle shapes——A molecular dynamics study

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science China Chemistry 2005年第5期48卷 470-475页

作者： GAO Jian1,2, GE Wei1 & LI Jinghai1 1. Multiphase Reaction Laboratory, Institute of Process Engineering, Chinese Academy of sciences, beijing 100080, China 2. graduate school of The Chinese Academy of sciences, beijing 100085, China Multiphase Reaction Laboratory Institute of Process Engineering Chinese Academy of Sciences Beijing China graduate school of The Chinese Academy of sciences Beijing China

Many aspects of the behavior of surfactants have not been well understood due to the coupling of many different mechanisms. Computer simulation is, therefore, attractive in the sense that it can explore the effect of different mechanisms separately. In this paper, the shapes, structures and sizes of sodium dodecylbenzenesulfonate (sDBs) micelles under different con-centrations in an oil/water mixture were studied via molecular dynamics (MD) simulations using a simplified atomistic model which basically maintains the hydrophile and lipophile properties of the surfactant molecules. Above the critical micellar concentration (cmc), surfactant molecules ag-gregate spontaneously to form a wide variety of assemblies, from spherical to rodlike, wormlike and bilayer micelles. Changes in their ratios of the principle moments of inertia (g1/g3, g2/g3) in-dicated the transition of micelle shapes at different concentrations. The aggregation number of micelle is found to have a power-law dependence on surfactant concentration.

关键词： surfactant, MD simulation, sodium dodecylbenzenesulfonate, micelle shape.

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 Center for Eco-Environmental sciences, Chinese Academy of sciences, beijing 100085, China 2. graduate school of the Chinese Academy of sciences, beijing 100039, China state Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing China graduate school of the Chinese Academy of sciences 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.

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

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多级闪蒸蒸发装置设计研究

水处理技术 1992年第3期18卷 180-186页

作者：周少祥华北电力学院北京研究生部 100085

本文根据多级闪蒸(MsF)过程的特点,借助于平均温度损失和平均端差等新概念,从最基本的热力学定律出发,推导出一套MsF 系统蒸发装置设计新方法。该方法的明显特点是简单、实用、精确。该设计计算模型的物理意义明确,各参数对MsF蒸发装置... 详细信息

本文根据多级闪蒸(MsF)过程的特点,借助于平均温度损失和平均端差等新概念,从最基本的热力学定律出发,推导出一套MsF 系统蒸发装置设计新方法。该方法的明显特点是简单、实用、精确。该设计计算模型的物理意义明确,各参数对MsF蒸发装置的影响均能很好地反映出来,因此为进行MsF 系统热经济学优化设计或分析提供了方便。

关键词：多级闪蒸海水淡化装置设计

Estimation of forest volumes by integrating Landsat TM imagery and forest inventory data

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science China(Technological sciences) 2006年第z1期49卷 54-62页

作者： GU Huiyan, DAI Limin, WU Gang, XU Dong, WANG shunzhong &WANG Hui Institute of Applied Ecology, Chinese Academy of sciences, shenyang 110016, China school of Forestry, Northeast Forestry University, Harbin 150040, China state Key Lab of systems Ecology, Research Center for Eco-Environmental sciences, Chinese Academy of sciences, beijing 100085, China graduate University of Chinese Academy of sciences, beijing 100039, China Institute of Applied Ecology Chinese Academy of Sciences school of Forestry Northeast Forestry University state Key Lab of systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

Accurate information about forest volumes is essential for forest management planning. The survey interval of the Forest Resource Inventory of China (FRIC) is too long to meet the demand for timely decision-making required for forest protection, management, and utilization. Analysis of satellite imagery provides good potential for more frequent reporting of forest parameters. In this study, we describe an application of the k-nearest neighbors (kNN) method to Landsat TM imagery for improving estimation of forest volumes. several spectral features were tested and compared in forest volume estimations, including normalized difference vegetation index, environmental vegetation index, and the combination of the spectral features. The combined index resulted in the most accurate volume estimations. The kNN estimator and the combined index were then used in forest volume estimation. The estimation error (RMsE) of the total volume was44.2%, much lower than those for Larix forest (the RMsE was 51.7%) and those for the Korean pine and broadleaved forests (the estimation errors were over 71.7% and 88.19%,respectively). This preliminary study demonstrates the potential of forest volume estimations with remote sensing data to provide useful information for forest management if only limited ground information is available.

关键词： forest inventory, landsat TM, k-nearest neighbors, spectral extraction.

The boundary of palaearctic and oriental realms in western China

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Progress in Natural science:Materials International 2008年第7期18卷 833-841页

作者： Ling Chen a,b,c, Yanling songd,*, shufang Xu e a Northwest Institute of Plateau Biology, Chinese Academy of sciences, Xining 810001, China b graduate University of the Chinese Academy of sciences, beijing 100039, China c National science Foundation of China, beijing 100085, China d Institute of Zoology, Chinese Academy of sciences, beijing 100101, China e beijing Academy of Agriculture and Forestry sciences, beijing 100097, China Northwest Institute of Plateau Biology Chinese Academy of Sciences Xining 810001 China graduate University of the Chinese Academy of sciences Beijing 100039 China National science Foundation of China Beijing 100085 China Institute of Zoology Chinese Academy of Sciences Beijing 100101 China beijing Academy of Agriculture and Forestry sciences Beijing 100097 China

In the world-wide zoogeographic division, there has been no consentaneous understanding about the delimitation between palaearctic and oriental realms in western China. In this study, we will discuss the division based on amphibian distribution in shaanxi, Gansu, sichuan, Yunnan, and Tibet according to species coefficient similarity between each zoogeographic province. The results show that the northern border lies from Qinling Mountains–Feng Xian (shaanxi)–Debu (Gansu)–Aba (sichuan)–Batang–Bomi (Tibet), to Linzhi districts, and the southern border is from Taibai–Feng Xian in shaanxi–Wen Xian (Gansu)–songpan–Kangding–Daocheng (sichuan), to Zhongdian–Gongshan in Yunnan, and westward to Motuo and Bomi district in Tibet.

关键词： Amphibian Zoogeography Palaearctic Oriental Hengduan Mt.

Determination of Chromate Ion in Water Using High Performance capillary Electrophoresis

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Chinese Chemical Letters 1997年第1期8卷 65-66页

作者： Qing GUO Li Wen CHANG Yu kian LI Hai Yu ZHA(Institute of Chemistry, Academia science, beijing 100080Research Center for Eco-environmental science, Academia science, beijing 100085graduate student, Institute of Chemical Engineering beijing United Univer Institute of Chemistry Academia Sinica Beijing 100080 Taiwan Res. Ctr. for Eco-Environ. science Academia Sinica Beijing 100085 China Institute of Chemical Engineering Beijing United University China

A new rapid method for the analysis of chromate ion in water by using high performance capillary electrophoresis is described. The detection limit is 1.0 mu g/ml by using 100 m mol/l Tris-HCl buffer containing 2 m mol/l 1,6-hexanediamine which was used as an electroosmosis modifier to improve the separation and detection sensitivity.

关键词： Determination of Chromate Ion in Water Using High Performance capillary Electrophoresis

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 graduate University of Chinese Academy of sciences

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.