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Effects of Different Grazing Intensities on Vegetation Characteristics of Cultivated Pastures in Southern china

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Animal Husbandry and Feed science 2012年第2期4卷 72-75,96页

作者： WAN Li-qiang,LI Xiang-lin ,HE Feng,CHEN Wei-wei,WAN Jiang-chun,ZHAO Yun,WU Wei-da institute of Animal sciences,chinese academy of Agricultural sciences,beijing 100193,china

[Objective]The paper was to study the effect of different grazing intensities on vegetation characteristics of artificial pasture by plot rota- tion grazing experiment. [Method]Grazing intensity was divided into 2 treatments of heavy grazing and light grazing,and each treatment contained 6 plots,with randomized complete block design. A blank control was set near test plot. Ninety disease-free and healthy 2-year-old Yunling Black Goats with consistent body condition were selected and divided into 2 groups： heavy grazing （ 55） and light grazing （ 35） . The goats were conduc- ted rotation grazing in 6 plots,and the average stocking rates were 12. 6 and 8 goat /hm 2 . The plant height,coverage,underground biomass and pasture plant nutrition of 2 treatments were measured,respectively. [Result]The cocksfoot height had significant difference with control under graz- ing conditions （ P 〈0. 05） ,while the heights of ryegrass and white clover in control plot had no significant difference with that in grazing plot （ P 〉 0. 05） . Grazing intensity had different effects on coverage of different plants; grazing utilization reduced the coverage of cocksfoot and ryegrass, which had little impact on coverage of white clover; viewed from the whole plant communities,the coverage in control plot was greater than that in grazing plot. The underground biomass in 0 -20 cm soil depth in grazing plot accounted for about 90%; with the increase of grazing intensity,un- derground biomass was decreased. The crude protein （ CP） and crude fat （ EE） content of forage decreased,while acid detergent fiber （ ADF） and neutral detergent fiber （ NDF） increased. [Conclusion]The research provided scientific basis for determination of suitable grazing system and sus- tainable utilization of pasture resources.

关键词： Grazing intensity Artificial pasture Vegetation characteristics

DISCOVERY　OF　LOWER　TRIASSIC　CONTOURITE　IN　SOUTHWESTERN　FUJIAN　PROVINCE　AND　ITS　SIGNIFICANCE

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Scientia Geologica Sinica 1994年第1期 115-118页

作者： Yang Meifang, Li Jiliang and Hao Jie(Lab. of the Lithosphere Tectonic Evolution, institute of Geology, chinese academy of science, beijing 100029)

ＤＩＳＣＯＶＥＲＹＯＦＬＯＷＥＲＴＲＩＡＳＳＩＣＣＯＮＴＯＵＲＩＴＥＩＮＳＯＵＴＨＷＥＳＴＥＲＮＦＵＪＩＡＮＰＲＯＶＩＮＣＥＡＮＤＩＴＳＳＩＧＮＩＦＩＣＡＮＣＥ￥ＹａｎｇＭｅｉｆａｎｇ，ＬｉＪｉｌｉａｎｇａｎｄＨａｏ... 详细信息

ＤＩＳＣＯＶＥＲＹＯＦＬＯＷＥＲＴＲＩＡＳＳＩＣＣＯＮＴＯＵＲＩＴＥＩＮＳＯＵＴＨＷＥＳＴＥＲＮＦＵＪＩＡＮＰＲＯＶＩＮＣＥＡＮＤＩＴＳＳＩＧＮＩＦＩＣＡＮＣＥ￥ＹａｎｇＭｅｉｆａｎｇ，ＬｉＪｉｌｉａｎｇａｎｄＨａｏＪｉｅ（Ｌａｂ．ｏｆｔｈｅＬｉｔｈ...

关键词： ITS SIGNIFICANCE PROVINCE AND CONTOURITE

Dependence of the solar cell performance on nanocarbon/Si heterojunctions

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chinese Physics B 2018年第7期27卷 595-600页

作者：肖仕奇范庆霞夏晓刚肖卓建陈辉亮席薇陈鹏辉李俊杰王艳春刘华平周维亚 beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences University of chinese academy of sciences beijing Key Laboratory for Advanced Functional Materials and Structure Research

Solar cells that combine single-crystalline silicon （Si） with graphene （G） have been widely researched in order to develop next-generation photovoltaic devices. However, the power conversion efficiency （PCE） of G/Si solar cell without chemical doping is commonly low due to the relatively high resistance of graphene. In this work, through combining graphene with carbon nanotube （CNT） networks, we fabricated three kinds of hybrid nanocarbon film/Si heterojunction solar cells in order to increase the PCE of the graphene based Si solar cell. We investigated the characteristics of different nanocarbon film/Si solar cells and found that their performance depends on the heterojunctions. Specifically, a doping-free G-CNT/Si solar cell demonstrated a high PCE of 7.9%, which is nearly equal to the combined value of two individuals （G/Si and CNT/Si）. This high efficiency is attributed to the synergistic effect of graphene and CNTs, and can be further increased to 9.1% after applying a PMMA antireflection coating. This study provides a potential way to further improve the Si based heterojunction solar cells.

关键词： carbon nanotube graphene heterojunction silicon solar cell

Thermosetting Polyimides Derived from 3,3’,4,4’-Benzophenone-Tetracarboxylic Dianhydride and Various Aromatic Diamines for Advanced Microelectronic Packaging

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Thermosetting Polyimides Derived from 3,3’,4,4’-Benzopheno...

Applications of stable isotopes to study plant-animal relationships in terrestrial ecosystems

5th International Symposium on High-Tech Polymer Materials

作者： Hong-yan Xu Hai-xia Yang Li-ming Tao Jin-gang Liu Lin Fan Shi-yong Yang Laboratory of Advanced Polymer Materials institute of Chemistry chinese academy of sciences Zhongguancun beijing 100190 china

＜正＞The rapid evolution in microelectronic technology is a well known *** polyimides,due to their excellent thermal,mechanical and electrical properties,play a significant role in achieving the current state-of-the-...

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chinese science Bulletin 2004年第22期49卷 2339-2347页

作者： WANG Jianzhu1,LIN Guanghui1,2,HUANG Jianhui1 & HAN Xingguo1 1.Key Laboratory of Quantitative Vegetation sciences and Research Center for Plant Ecology and Biodiversity Conservation,institute of Botany,chinese academy of sciences,beijing 100093,china 2.Department of Global Ecology,Carnegie Institution of Washington,Stanford,CA 94305,USA Key Laboratory of Quantitative Vegetation sciences and Research Center for Plant Ecology and Biodiversity Conservation Institute of Botany Chinese Academy of Sciences Beijing 100093 China Department of Global Ecology Carnegie Institution of Washington Stanford CA 94305 USA

As natural tracers, stable isotopes have been extensively used in plant physiological, ecological and envi- ronmental research. Recently, animal physiological ecologists have also applied stable isotope techniques to study plant- animal relationships. The isotopic compositions of animal body generally reflect and integrate their diets over a time period ranging from hours to years to the lifetime of an indi- vidual. When animal living habitat changes or animals move to a new environment, the animal isotopic compositions will shift accordingly. Thus, stable isotope signatures of an ani- mal can truly reflect its food sources, habitat, distribution and movement patterns during a given time period. More- over, by analyzing animal-tissue isotopic compositions at different temporal scales, we can improve our understanding of animal adaptation to environmental changes. Stable iso- tope technique also provides an ideal tool to study animal foodweb relationship and community structure because of isotopic fractionation during the processes of nutrient as- similation by animals. Stable isotope technique can continu- ously measure animal trophic position in a foodweb, which can eventually reveal the predator-prey relationship and its role in determining matter balance and energy flow in the entire ecosystem. Stable isotope technique has been one of the most important and efficient tools in studying plant-animal relationship. In this paper, we first review recent advances in the application of stable isotope techniques to plant-animal relationship research then evaluate their advantages and disadvantages, and finally discuss some future directions associated with stable isotope applications to plant-animal relationship research.

关键词：稳定同位素植物-动物关联性食物来源营养水平动物迁移

线粒体内膜解偶联蛋白UCP1在大肠杆菌中的活性表达(英文)

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生物化学与生物物理进展 2010年第1期37卷 56-62页

作者：周强军孙吉翟宇佳孙飞中国科学院生物物理研究所生物大分子国家重点实验室北京100101

线粒体的呼吸耗氧偶联着ATP的合成,而位于线粒体内膜上的跨膜蛋白解偶联蛋白(uncoupling protein,UCP)能够破坏这种偶联关系.在大肠杆菌中表达了有生物活性的鼠源解偶联蛋白1(rUCP1).重组rUCP1的表达导致大肠杆菌宿主细胞生长变慢;在电... 详细信息

线粒体的呼吸耗氧偶联着ATP的合成,而位于线粒体内膜上的跨膜蛋白解偶联蛋白(uncoupling protein,UCP)能够破坏这种偶联关系.在大肠杆菌中表达了有生物活性的鼠源解偶联蛋白1(rUCP1).重组rUCP1的表达导致大肠杆菌宿主细胞生长变慢;在电子显微镜下观察免疫标记的结果显示,重组rUCP1主要表达在细菌膜上;同时将rUCP1重构到脂质体中也能够测到质子转运活性.这些结果说明,真核生物UCP1能够在原核生物中表达出有生物活性的形式,且能纯化得到足量的rUCP1蛋白用于进一步的结构生物学研究.

关键词：线粒体解偶联蛋白原核表达免疫电镜膜蛋白脂质体

lonization and dissociation of acetonitrile by intense femtosecond laser pulse

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chinese science Bulletin 2000年第21期45卷 1953-1955页

作者： WU Chengyin, XIONG Yijia, GAO Zhen, KONG Fan’ao, LU Haihe, YANG Xiaodong & XU Zhizhaninstitute of Chemistry, chinese academy of sciences, beijing 100080, china Shanghai institute of Optics and Fine Mechanics, chinese academy of sciences, Shanghai 201800, china Correspondence should be addressed to Kong Fan’ao

Photoionization and photodissociation of CH3CN were studied by a linear time of flight mass spectrometer coupled with 800 nm, 50 fs laser pulses at intensities of 6.3×1013-1.2×1014 W/cm2. The laser power dependences for principal ions CH3CN+, CH2CN+, CHCN+ and CCN+ were measured, which are consistent with the numbers of photons required to produce the ions via multiphoton ionization and dissociation. The results show that eight-photon non-resonant multiphoton ionization is the main photoionization mechanism of the parent ion CH3CN+, while the fragment ions were produced through the dissociation of the molecules in the super-excited states.

关键词： femtosecond laser multiphoton ionization field ionization super-excited state.

THE GLOBAL TECTONIC systems AND A LATITUDINAL MOUNTAIN-PLATEAU CHAIN ON THE NORTH HEMISPHERE

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地学前缘 2000年第S1期7卷 344-345页

作者： Ma Zongjin(institute of Geology,china Seismological Bureau,beijing 100029,china)

Three global tectonic systems that formed since the middle Jurassic (160Ma ago)are outlined based on the global map of the Cenozoic and Mesozoic tectonics edited by Ma Zongjin et al.(1996).They are the circum\|Pacific tectonic system,the mid\|ocean ridge tectonic system and the intra\|continental tectonic system of the north *** map shows that about 80% of the total length of the continental orogens are concentrate on the north hemisphere of the earth,of which a latitudinal mountain\|plateau chain occur within a zone between north latitude 20°and 50°.Seismic and volcanic activities demonstrate that the intracontinental tectonic system on the north hemisphere is still *** distribution of the continental deep\|focus earthquakes and almost ultra high\|pressure rock found so far over the World,that are assumed both related to recent or previous deep subduction of continent,along with this *** latitudinal mountain\|plateau chain is subdivided into four active tectonic region of Qinghai—Xizang(Tibet),Iranian,eastern mediterranean and North American,both characterized by an individual similar mountain\|plateau\|basin structure with major active boundaries or controlling faults (Fig.1).These active regions are all close to primary dynamic boundaries of continent\|continent *** of source mechanisms shows that regional tectonic stress field in these regions are dominated by a nearly NS or NNE—SSW direction compression corresponding to a local plate motions and a global compressive *** between the formation of the continental latitudinal mountain\|plateau chain on north hemisphere and the oceanic plate tectonics is discussed using the information of the “Map of Magnetic Lineations of the World’s Ocean Basins (Cande et al.,1989)”and the Cenozoic and Mesozoic tectonic evolution in the *** 49 accretion units formed during 6 accretion stages of the ocean spreading in three chief oceans (the Pacific,the India and th

关键词： global asymmetrical system geodynamics mountain\| plateau chain seismotectonic system latitudinal tectonic zone

THE DISTRIBUTION OF PREFERENTIAL PATHS AND ITS RELATION TO THE SOIL CHARACTERISTICS IN THE THREE GORGES AREA,china

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International Journal of Sediment Research 2007年第1期22卷 39-48页

作者： Hongjiang ZHANG1, Jinhua CHENG2, Yuhu SHI3, and Yun CHENG41 Prof., 2,4 Lecturer College of Soil and Water Conservation, P O box 67, beijing Forestry University, No. 35 Qinghua East Road, beijing, 100083, china, 3 Assoc. Prof., Forestry science institute of Hubei Province, Wuhan, 430075, china beijing Forestry Univ Coll Soil & Water Conservat Beijing 100083 Peoples R China Forestry Sci Inst Wuhan 430075 Hubei Peoples R China

To study the characteristics of the distribution of the preferential paths and the affecting factors in the Three Gorges area, four soil profiles were dug to observe the distribution of preferential paths in the Quxi watershed in the Yangtze River basin. The Morisita exponential test method was used to examine the distribution type of preferential paths. The physical properties and infiltration characteristics of the soil were also measured to evaluate their relationship to preferential paths. The results showed that in this area, preferential paths clustered and mainly distributed in the 80-100 cm soil layer, and along the interface between the weathered layer and semi-weathered layer. There were more non-capillary pores in the 83-110 cm layer than in the other layers. It can be derived that most non-capillary pores in this layer were preferential paths caused by geological processes and rotten plant roots. The percentage of coarse soil particles increased with the depth of the soil layer. In the deeper soil layer, the coarse soil particles helped the formation of preferential paths. The fastest steady infiltration rate was observed in the of 83-110cm layer, which is inferred to be due to the greater number of preferential paths.

关键词： Preferential paths Morisita exponential test Physical properties of soil Infiltration characteristics of soil