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Changes in plant biomass and species composition of alpine Kobresia meadows along altitudinal gradient on the Qinghai-Tibetan Plateau

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Science china(Life sciences) 2008年第1期51卷 86-94页

作者： WANG ChangTing1,3. CAO GuangMin1, WANG QiLan1, JING ZengChun1, DING LuMing1 & LONG RuiJun2.1 Northwest institute of Plateau Biology, Chinese {2. of {4., Xining 810001,{3. 2.College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 73.070,{3. 3.Graduate University of the Chinese {2. of {4., beijing 10003.,{3. 1. Northwest institute of Plateau Biology Chinese Academy of Sciences Xining 810001 China 3. Graduate University of the Chinese academy of {2. Beijing 100039 China 2. College of Pastoral Agriculture Science and Technology Lanzhou University Lanzhou 730070 China

Alpine Kobresia meadows are major vegetation types on the Qinghai-Tibetan Plateau. There is growing concern over their relationships among biodiversity, productivity and environments. Despite the im-portance of species composition, species richness, the type of different growth forms, and plant bio-mass structure for Kobresia meadow ecosystems, few studies have been focused on the relationship between biomass and environmental gradient in the Kobresia meadow plant communities, particularly in relation to soil moisture and edaphic gradients. We measured the plant species composition, her-baceous litter, aboveground and belowground biomass in three Kobresia meadow plant communities in Haibei Alpine Meadow Ecosystem Research Station from 2.01 to 2.04. Community differences in plant species composition were reflected in biomass distribution. The total biomass showed a de-crease from 13.96.96±719.69 g/m2.in the sedge-dominated K. tibetica swamp to 2.69.58±14..52.g/m2.in the forb and sedge dominated K. pygmaea meadow, and to 2.53.08±14..95 g/m2.in the forbs and grasses dominated K. humilis along with the increase of altitude. The vertical distribution of below-ground biomass is distinct in the three meadow communities, and the belowground biomass at the depth of 0-10 cm in K. tibetica swamp meadow was significantly higher than that in K. humilis and K. pygmaea meadows (P<0.01). The herbaceous litter in K. tibetica swamp was significantly higher than those in K. pygnaeca and K. humilis meadows. The effects of plant litter are enhanced when ground water and soil moisture levels are raised. The relative importance of litter and vegetation may vary with soil water availability. In the K. tibetica swamp, total biomass was negatively correlated to species richness (P<0.05); aboveground biomass was positively correlated to soil organic matter, soil moisture, and plant cover (P<0.05); belowground biomass was positively correlated with soil moisture (P<0.05). However, in the K. py

关键词： plant species richness plant litter aboveground biomass belowground biomass soil moisture alpine meadow

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Synthesis and Characterization of Polyurethane

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Journal of Wuhan University of Technology(Materials Science) 2010年第6期25卷 984-986页

作者：贺纯静倪家骧 Department of Pain Xuanwu HospitalCapital Medical University

Polyurethane was synthesized by the copolymerization with isocyanate and *** structure and properties of the copolymers were characterized by infrared spectrometer（IR）,differential scanning calorimetry（DSC） and thermogravimetry（TG）.The rabbit blood samples was dripped on the polyurethane,which was prepared by drying and die,and the contact angle was measured by contact angle measurement,then infiltration phenomenon was observed by electron *** results showed that the contact angle of blood samples and polyurethane was decreased with increasing time,and the platelets on the polyurethane would gradually increase and more *** the polyurethane coating had good hydrophilic property and anticoagulant activity.

关键词： polyurethane hydrophilicity anticoagulant

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The Antimutagenic and Anticarcinogenic Effects of Tea, Garllc and Other Natural Foods in china: A Review

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Biomedical and Environmental sciences 1992年第1期5卷 1-17页

作者： CHEN JUNSHIinstitute of Nutrition and Food Hygiene, Chinese academy of Preventive Medicine, 2. Nan WeiRoad, {2. 100050,{{4. institute of Nutrition and Food Hygiene Chinese Academy of Preventive Medicine Beijing.

It is well known that there are huge geographic variations in cancer rates in china's Mainland. For example, The National Cancer Control Office of the Ministry of Public Health (1979) reported that in the 1970s, cancer mortality rates for most cancers were found to be more than 2.-fold greater in some counties in others (Table 1). Esophageal cancer rates for males are a few hundred fold greater in the highest county when compared with the lowest county. The mortality rate for all cancers combined for males is 2. fold greater in the county with the highest mortality than in the county with the lowest *** to Doll and Peto (1981), about one third of human cancer death is avoidable by appropriate modification of the diet. Therefore, diet is very likely to have an important part in causing these huge geographic variations. The possible role of various mutagens and carcinogens (e.g. afiatoxin, N-nitroso compounds) in locally produced and consumed foods has been strongly suggested and widely acknowledged, although much more evidence would be required to confirm their actual functions in human cancer. On the other hand, there are a few reports stating that the human diet also contains powerful antimutagens and anticarcinogens (Ames, 1983.. The possible role of these two types of substances in causing the huge geographic variation of cancer risks remains elusive and inadequately explored. In order to make better use of these natural anticarcinogens in cancer prevention, it is important to elucidate their effects and mechanisms. The purpose of this paper is to summarize the available information on the antimutagenic and anticarcinogenic effects of natural foods in the Chinese diet, excluding the effects of essential nutrients, e.g. dietary fibers, vitamins and {2.s. Most of the literature cited in this review was published by Chinese scientists.

关键词： The Antimutagenic and Anticarcinogenic Effects of Tea A Review Garllc and Other Natural Foods in china

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Sequence Stratigraphy and Tectonic Environment of the Chartai Group,Inner Mongolia

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Acta Geologica Sinica(English Edition) 1991年第3期65卷 217-235,341-342页

作者： Qiao Xiufu Yao Peiyi Wang Chengshu Tan Lin Zhu Shenyu Zhou Shengde Zhang Yuqing institute of Geology,Chinese academy of Geological {2., {3. Regional Geological Survey Party,Geological Bureau of Inner Mongolia,Hohhot Sun Sheping institute of Geology Chinese Academy of Geological Sciences Beijing China

The Middle Proterozoic Chartai Group separated by two unconformities consists of three depositional se-quences: the Shujigou Formation-Zenglongchang Formation (DS Ⅰ), the Agulugou Formation (DS Ⅱ), andthe Liuhongwan Formation (DS Ⅲ). The carbonate platform and back-platform basin are the basic environ-ment model of the Chartai Group. The syndepositional faults on the oceanward side of the carbonate platformand large-scale slumping in the soft sediments are important marks of facies tracts. The newly establishedZenglongchan uplifting, an epeirogenetic uplifting, plays an important role in the formation of thepalaeogeographic framework of the Chartai Group. The stratigraphic correlation between the Chartai Groupand the Bayan Obo Group is made for the first time by using sequence stratigraphic principle and model estab-lished by P.R. Vail. The Chartai Group, which was deposited on the northern passive continental margin of theNorth china platfom, represents the platform cover.

关键词： Sequence Stratigraphy and Tectonic Environment of the Chartai Group Inner Mongolia

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Knob-associated tandem repeats on mitotic chromosomes in Zea diploperennis, maize and theirs hybrids

Knob-associated tandem repeats on mitotic chromosomes in Zea...

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湖北省遗传学会第七次代表大会暨学术讨论会

作者： XIONG Zhiyong~(1.2., GAO Yuan~1, HE Guanyuan~2. GU Mingguang~3. GUO Lequn~3.& SONG Yunchun~(1*) (1. Key Lab of the Ministry of Education for Plant Developmental Biology, Wuhan University, Wuhan 4.2}072. china 2. china-UK HUST-RRes Crop Genetic Engineering and Genomics Joint Laboratory, Huazhong University of Science and Technology, Wuhan 4.2}074. china 3. {3. of Genetics, The Chinese academy of {14., beijing 1000101, china)

Knob-associated tandem repeats, 180-bp repeats and TR-1 elements, together with 4.S rDNA were located on mitotic chromosomes of Zea diploperennis (DP), maize inbred line F102.and theirs hybrid. In DP, knobs on chromosomes 1S, 4., 4. and 5S are composed predominantly of the 180-bp repeats. In addition, 180-bp repeats co-exited with TR-1 elements were also detected in other seven sites on six chromosome pairs. In maize inbred line F102. 180-bp repeats were present in chromosomes 7S and one homologue of chromosomes 8L. TR-1 elements appeared on satellite of chromosome 6 and no detectable hybridization site co-located with 180-bp repeats was observed in maize F102. Polymorphism of size, number, and distribution of 180-bp repeats and TR-1 were revealed among different chromosomes and between homologous chromosomes in these two species. Using these excellent landmarks, the interspecific hybrid of maize and DP were identified. The results presented suggestthat comparative analysis of 180-bp repeats and TR-1 elements may aid in understanding the genome organization and the evolution in Zea.

关键词： Zea mays Zea diploperennis repetitive DNA sequence fluorescence in situ hybridization heterochromatic knob.

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Mechanism of catalytic hydropyrolysis of sedimentary organic matter with MoS_2

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Petroleum Science 2011年第2期8卷 134-142页

作者： He Kun Zhang Shuichang Mi Jingkui Chen Jianping Cheng Lei Petroleum Geology Research and Central Laboratory Research Institute of Petroleum Exploration and Development （RIPED） PetroChina Beijing 100083 China CNPC Key Laboratories for Petroleum Geochemistry Beijing 100083 China

MoS2.was used as an efficient catalyst for hydropyrolysis （Hypy） of three samples of sedimentary organic matter with different maturities. Through comparison with Soxhlet extraction （SE）, it was found that MoS2.catalytic Hypy can remarkably promote the yields of total chloroform extracts, saturates, aromatics, hopanes and steranes. In addition, the difference of biomarker parameters indicated that isomerization of covalently-bound biomarkers is much more difficult than their free counterparts. Meanwhile, the high conversion of total organic carbon （TOC） in MoS2.catalytic Hypy of organic matter proved that the presence of dispersed molybdenum sulfide accelerated the breaking of C-C bonds and the release of hydrocarbons. To address the catalytic mechanism, a series of control experiments based on free Hypy and catalytic Hypy were conducted. The results showed that the calculated atomic ratio of carbon conversion/hydrogen conversion for catalytic Hypy was much larger than the presumed value of 1/2. indicating that intensive hydrogenation took place and significantly influenced the distribution of liquid products. Analysis of stable hydrogen isotope data, infrared spectra and m/z 8{4.ion chromatograph of the saturate fraction further confirmed this hypothesis. The difference of S content changing （AS） between catalyst-free Hypy and catalytic Hypy, and the thermal characteristics of the catalyst, indicated that active H2. was definitely generated and it probably initiated free radical reactions in the early stage of hydropyrolysis of organic matter.

关键词： Catalytic hydropyrolysis molybdenum disulfide kerogen coal Soxhlet extraction,biomarkers

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REVERSE-RANGE-DOPPLER METHOD FOR AUTOMATED GEOCODING SAR IMAGES

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Journal of Electronics(china) 2012年第Z2期 242-247页

作者： Liu Jiayin* *** Hong Wen** *** *(Key Laboratory of Technology on Geo-spatial Information Processing and Application System, Chinese academy of sciences, {2. 100190,{3.) **(National Key Laboratory of Microwave Imaging Technology, {2. 100190,{3.) ***(institute of Electronics, Chinese academy of sciences, {2. 100190,{3.)

Range-Doppler (RD) method and Reverse-Range-Doppler (RRD) method are combined together to achieve automatic geocoding of Synthetic Aperture Radar (SAR) image quickly and accurately in the paper. The RD method is firstly used to locate the four corners of the image, then the other pixels of the image can be located by Reverse-Range-Doppler (RRD) method. Resampling is performed at last. The approach has an advantage over previous techniques in that it does not require ground control points and is independent of spacecraft attitude knowledge or control. It can compensate the shift due to the assumed Doppler frequency in SAR image preprocessing. RRD simplifies the process of RD, therefore speeds up the computation. The experimental results show that a SAR image can be automated geocoded in 3. s using the single CPU (3.GHz) with 1 G memory and an accuracy of 10 m is attainable with this method.

关键词： Range-Doppler (RD) Reverse-Range-Doppler (RRD) Geolocation Automated geocoding Space-borne Synthetic Aperture Radar (SAR)

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鸡贫血病毒VP3.白序列与其核定位功能的相关性

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生物化学与生物物理进展 2002年第1期29卷 100-104页

作者：陶冶张靖溥中国科学院发育生物学研究所北京100080

鸡贫血病毒 (chickenanemiavirus ,CAV)编码一种小蛋白VP3.通过构建vp3.因与绿色荧光蛋白基因的真核融合表达载体 ,转染 5种肿瘤 /转化细胞株 ,观察绿色荧光在亚细胞区域的定位 ,证实VP3.有核定位的功能 ;分析VP3.氨基酸序列 ,将其... 详细信息

鸡贫血病毒 (chickenanemiavirus ,CAV)编码一种小蛋白VP3.通过构建vp3.因与绿色荧光蛋白基因的真核融合表达载体 ,转染 5种肿瘤 /转化细胞株 ,观察绿色荧光在亚细胞区域的定位 ,证实VP3.有核定位的功能 ;分析VP3.氨基酸序列 ,将其具核定位序列 (nuclearlocalizationsequence ,NLS)特征的区域删除 ,再构建此缺失的VP3.基因与绿色荧光蛋白基因的真核融合表达载体、转染实验显示核定位现象消失 ;进一步将具核定位序列特征的区域亚克隆到绿色荧光蛋白真核表达载体上 ,核定位功能再现 .从而推断这一区域是VP3.白核定位的功能区 .此区域位于VP3.C端 ,且富含碱性氨基酸 ,二级结构预测发现这一区域形成特定的 β折叠结构 .用碘丙锭 (propidiumiodide,PI)染色的方法还得到了VP3.进肿瘤细胞凋亡的初步证据 .

关键词： VP3.白肝癌细胞系绿色荧光蛋白脂质体转染核定位序列细胞凋亡鸡贫血病毒相关性

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南海东部海域表层沉积物类型的研究

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海洋学报 2004年第5期26卷 94-105页

作者：张富元章伟艳张德玉辛春英孟翊陈荣华国家海洋局海底科学重点实验室国家海洋局第一海洋研究所山东青岛266061 华东师范大学

南海东部海域表层沉积物可被分为11种类型:含岩块砾石黏土质粉砂、贝壳珊瑚砂、黏土质粉砂、钙质黏土、钙质软泥、有孔虫砂、深海黏土、含铁锰微粒粉砂质黏土、硅质黏土、含火山灰硅质黏土、含火山灰粉砂质黏土.这些类型按物源和成因可... 详细信息

南海东部海域表层沉积物可被分为11种类型:含岩块砾石黏土质粉砂、贝壳珊瑚砂、黏土质粉砂、钙质黏土、钙质软泥、有孔虫砂、深海黏土、含铁锰微粒粉砂质黏土、硅质黏土、含火山灰硅质黏土、含火山灰粉砂质黏土.这些类型按物源和成因可被分为陆源碎屑、钙质碎屑和硅质碎屑、火山碎屑3.类型,其中陆源碎屑分布面积约占50%,钙质碎屑占2.%,硅质碎屑和火山碎屑各占15%.在物质来源、海底地形、火山作用、生物作用、水动力条件等因素影响和控制下,由于沉积环境的差异,故区内褐色类沉积物最多(60 68%),灰色类沉积物次之(3. 2.%),黄色类沉积物最少(1 12.).台湾省以南到17°N以北海区沉积物以陆源沉积物分布为主;巴士海峡以西海区沉积物较粗,常含砂岩块和砾石;东沙群岛以东海区钙质生物碎屑沉积丰富;中、西部海区以含铁锰微粒沉积物为主;中、南部海区水深大,主要分布硅质沉积物;南部海区、礼乐滩北缘沉积物受礼乐滩珊瑚碎屑影响大,沉积物类型为钙质软泥.

关键词：南海东部表层沉积物沉积物类型沉积环境沉积作用

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Professor Beranek's criteria about Acoustical parameters in concert hall acoustics

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Chinese Journal of Acoustics 2003年第2期22卷 121-131页

作者： LIU Ke ZHOU Qijun(institute of Acoustics, The Chinese academy of {2. {3. 100080)

Professor Beranek talked about the sound qualities of concert hall. The 58 famous concert halls in the world were graded according to the subjective comparison from the professional musicians and music lovers. Six mea... 详细信息

关键词： in on it Hall Professor Beranek’s criteria about Acoustical parameters in concert hall acoustics is of

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