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Astronomical function and date of the Taosi observatory

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science {1.(Physics,Mechanics & Astronomy) 2009年第1期52卷 151-158页

作者： WU JiaBi1. CHEN MeiDong2.& LIU CiYuan3 1.National Astronomical Observatories,{1., Beijing 1.001.0} china 2.{2. for the History of natural science,{1., Beijing 1.001., china 3 National Time Service Center,{1., Xi’an 71.600, china National Astronomical Observatories Chinese Academy of Sciences Beijing China institute for the History of {1. {2. Chinese Academy of Sciences Beijing China National Time Service Center Chinese Academy of Sciences Xi’an China

The Taosi site in Xiangfen County,Shanxi Province,may be the capital of the King Yao. Archeologists recently discovered a large semi-circular stamped-earth platform, II FJT1.which has a clear and definite pounded-earth central core together with a curved wall perforated by twelve gaps. The platform is said to be an ancient observatory used to determine the seasons by watching the sunrise. Each feature of II FJT1.was precisely measured and the data are reproduced in this paper. An astronomical analysis of slots E2.and E1.0}was carried out using the azimuths of the slots' centerlines and the vertical angle of the mountain ridge opposite, above which the sun rises. The results show that at present the sun is close to the two slots but does not exactly enter them at summer and winter solstice sunrise. Using 1.C analysis archeologists dated the site to about 2.00 BC. Because of the secular change in the obliquity of the ecliptic,at that date on the summer solstice the half-risen sun would have appeared inside slot E1.0}just to the right of the centerline,and on the winter solstice the sun would have been exactly on the centerline of slot E2. This result provides compelling proof that II FJT1.is an ancient observatory.

关键词： astro-archeology astro-chronology Taosi culture ancient observatory time service

Analysis and Modeling on the Spatial Structure of Urban Land Use: A Case of Jinan, china

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chinese Journal of Population,{1. and Environment 2007年第2期5卷 34-40页

作者： Zhao Huixia1. 3, Zhang Zulu2. Jiang Luguang 1.1. {1. of geographical {2. and natural resources Research, chinese academy of sciences, Beijing 1.01.1. china 2. College of Population, resources and Environment, Shandong Normal University, Jinan Shandong 2.001., china 3. Graduate School of the chinese academy of sciences, Beijing 1.0039, china institute of {1.al {2. and natural resources Research Chinese Academy of Sciences Beijing 100101 China Graduate School of the chinese academy of sciences Beijing 100039 China College of Population Resources and Environment Shandong Normal University Jinan Shandong 250014 China

Based on the data of urban land use obtained by remote sensing interpretation from aero images in 1.86 and 2.04, the spatial structure of Jinan is studied in this paper with the method of {1. Information System (GIS). According to the proportion of land for residence, industry and commerce, the urban district can be distinguished into three rings. Compared with the traditional theory of the ring structure in Western coun- tries, they have many distinctive characteristics. The main func- tions of the inner ring include residence, business and banking, but the proportion of residential land (more than 50%) is considerably higher than that of the cities in Western countries. The land proportion for residence and industry in the intermediate ring is equal on the whole. The main land of the outside ring is for industrial use. From 1.86 to 2.04, great changes have taken place on the land proportion of different types of use. In the inner ring, the land for residential and industrial use has shrunk much while the land for commercial use has increased. In the intermediate ring, the changes of the three types of land use were not very much and the temporal variation was relatively stable. On the contrary, the structure in the outside ring varies acutely. Though most of it is also for industrial use, the proportion of residential land has in- creased much. The three rings can also be divided into several sectors respectively, according to the function of land use clusters. New trends and mechanisms of the changes of land use impacting the urban structure were proposed in the end of the paper.

关键词： urban land use ring structure sector structure Jinan

The identity of some taxa of Schizophragma (Saxifragaceae)

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Journal of Systematics and Evolution 2009年第2期47卷 151-161页

作者： 1.2.ei LIU 1.iang-Yun ZHU 1.{1. of Botany,chinese {2. of sciences,Beijing 1.0093,china) 2.Graduate University of chinese academy of sciences,Beijing 1.0049,china) institute of Botany Chinese Academy of Sciences Beijing 100093 China Graduate University of chinese academy of sciences Beijing 100049 China

After examining a large number of type and authoritative specimens of Schizophragma Siebold & Zucc.,*** *** and *** *** Rehder were reduced to synonyms of *** Rehder and *** *** *** was reduced to synonym of *** *** crassum *** *** was treated as the correct name of *** ***(Chun) *** name *** *** Rehder is *** taxonomic treat-ment is supported by leaf epidermal characters.

关键词： leaf epidermis new synonym reinstatement Schizophragma

Comparative analysis of temperature and CO2.fluxes for winter wheat in Tibetan Plain and North {1. Plain using the EMD method

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Progress in natural {1.:Materials International 2006年第10期16卷 1066-1071页

作者： JIANG Zhaoyang, YU Qiang, LEI Shuhe, WANG Tianduo, SUN Xiaomin and ZHANG Renhua ( chinese academy of Meteorological {2., Beijing 100081, china institute of geographic sciences and natural resources Research, chinese academy of sciences, Beijing 1.01.1. china Mathematics Department, Ocean University of china, Qingdao 2.6071, china Shanghai institute of Plant Physiology and Ecology, chinese academy of sciences, Shanghai 2.0032. china) chinese {1. of Meteorological {2. Beijing 100081 China institute of {1. {2. and natural resources Research Chinese Academy of Sciences Beijing 100101 China Mathematics Department Ocean University of China Qingdao 266071 China Shanghai institute of Plant Physiology and Ecology Chinese Academy of Sciences Shanghai 200032 China

Comparative study of spectral properties of temperature and CO2.fluxes measured by eddy covariance method at Yucheng (36°57'N, 1.6°36'E, 2. m a.s.l., in the North china Plain) and at Lhasa (2.°41.N, 91.2.'E, 3688 m a.s. 1., on the Tibetan Plateau) is described using the empirical mode decomposition (EMD) method. The main results are: (1. The intrinsic oscillation modes or intrinsic mode functions (IMFs) were extracted from data of temperature ( T) and CO2.fluxes (F) measured at Yucheng ( T1.and F1. and Lhasa ( T2.and F2. . (2. Hilbert transform was applied to these IMF components, then the Hubert-Huang spectra and the marginal spectra of these data were obtained. (3) Comparison of temperature and CO2.fluxes in North china Plain and on Tibetan Plain illustrated that the characteristic frequencies corresponding to T1. F1. T2.and F2.are 0.05 Hz, 0.03 Hz, 0.01. Hz and 0.005 Hz, respectively.

关键词： empirical mode decomposition (EMD) intrinsic mode function (IMF) flux Hilbert transform wheat Tibet.

Transient species and its properties of melatonin

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science {1. Chemistry 2006年第4期49卷 308-314页

作者： ZHU Hongping1.2. ZHANG Zhaoxia1.2. ZHAO Hongwei1. WANG Wenfeng1.& YAO Side1.1. Shanghai institute of Applied Physics, chinese academy of sciences, Shanghai 2.1.00, {2. 2. Graduate University of the chinese academy of sciences, Beijing 1.0049, {2. Shanghai institute of Applied Physics Chinese Academy of Sciences Shanghai China Graduate University of the chinese academy of sciences Beijing China

The photo-physical and photo-chemical properties of melatonin (ML) werestudied by 2.6 nm laser flash photolysis (LFP). ML undergoes photo-ionization to produce radicalcation of ML (ML^(·+))and hydrated electrons (e_(aq)^-), while excited triplet state ~3ML~* is alsoformed during photolysis. The oxidation via one electron transfer from ML to SO_4^(·+) and thetriplet state of riboflavin (~3RF~*) has been also investigated and the rate constants for theprocess have been determined to be 8.0x1.^9 and 1.4x1.^9 L·mol^(-1.·s^(-1. respectively. Theradical cation of 2.2.'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS^(·+)) scavengingcapacities of melatonin and other antioxidants are compared in this paper.

关键词： melatonin, laser flash photolysis, photoionization, triplet state.

Large-scale boron nanowire nanojunctions and their highly-oriented arrays

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science {1.(Physics,Mechanics & Astronomy) 2004年第5期47卷 621-632页

作者： CAO Limin1.2. ZHANG Ze2.& WANG Wenkui1.2.1. Key Laboratory of Metastable Materials science and Technology, Yanshan University, Qinhuangdao 066004, china 2. {2. of Physics, chinese academy of sciences, Beijing 1.0080, china Key Laboratory of Metastable Materials science and Technology Yanshan University Qinhuangdao China institute of Physics Chinese Academy of Sciences Beijing China

Highly oriented multiple boron nanowire nanojunctions with unilateral feather- like morphology were first successfully prepared using a radio-frequency magnetron sputtering method. The branched boron nano-feathers always nucleate and grow on the same sidewall of the stems, and align in parallel to form multiple T- and/or Y-type nanojunctions. The diameters of the branches and the stems are in the range of 2.—40 and 60—80 nm, respectively. The thinner branches and thicker stems of the boron nanowires self-assembled into large-scale, highly ordered arrays on various substrates. During the formation and self-assembly of the arrays, no template or catalyst was needed. We believe that the approach presented here can be used to fabricate heterostructures with bottom-up assembly of a wide variety of one-dimensional nanostructures via the rational design of targets and the proper control of the experimental conditions.

关键词： boron nanowires, nanojunctions, self-assembly, magnetron sputtering.

The retrieval of two-dimensional distribution of the earth's surface aerodynamic roughness using SAR image and TM thermal infrared image

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science {1. Earth {2. 2004年第12期47卷 1134-1146页

作者： ZHANG Renhua 1 ,WANG Jinfeng 1 ,ZHU Caiying 1,2.,SUN Xiaomin 1 & ZHU Zhilin 1 1.institute of geographical {2. and natural resources,chinese academy of {2.,Beijing 1.01.1.china 2.institute of Surveying and Mapping,Information Engineering University of the chinese People’s Liberation Army,Zhengzhou 450052.china chinese {1. of {2. Institute of Geographical Sciences and Natural Resources Beijing China Information Engineering University of the chinese People’s Liberation Army Institute of Surveying and Mapping Zhengzhou China

After having analyzed the requirement on the aerodynamic earth’s surface rough- ness in two-dimensional distribution in the research field of interaction between land surface and atmosphere, this paper presents a new way to calculate the aerodynamic roughness using the earth’s surface geometric roughness retrieved from SAR (Synthetic Aperture Radar) and TM thermal infrared image data. On the one hand, the SPM (Small Perturbation Model) was used as a theoretical SAR backscattering model to describe the relationship between the SAR back- scattering coefficient and the earth’s surface geometric roughness and its dielectric constant re- trieved from the physical model between the soil thermal inertia and the soil surface moisture with the simultaneous TM thermal infrared image data and the ground microclimate data. On the basis of the SAR image matching with the TM image, the non-volume scattering surface geo- metric information was obtained from the SPM model at the TM image pixel scale, and the ground pixel surface’s equivalent geometric roughness—height standard RMS (Root Mean Square) was achieved from the geometric information by the transformation of the typical to- pographic factors. The vegetation (wheat, tree) height retrieved from spectrum model was also transferred into its equivalent geometric roughness. A completely two-dimensional distribution map of the equivalent geometric roughness over the experimental area was produced by the data mosaic technique. On the other hand, according to the atmospheric eddy currents theory, the aerodynamic surface roughness was iterated out with the atmosphere stability correction method using the wind and the temperature profiles data measured at several typical fields such as bare soil field and vegetation field. After having analyzed the effect of surface equivalent geo- metric roughness together with dynamic and thermodynamic factors on the aerodynamic surface roughness within the working area, this paper first establishe

关键词： surface geometric roughness, aerodynamic surface roughness, SAR backscattering model, moisture retrieval model, roughness transformation model.

Relationship between Surface Pollen and Modern Vegetation in Southwestern china

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Journal of Mountain science 2010年第2期7卷 176-186页

作者： PAN Tao DAI Erfu and WU Shaohong institute of {1. {2. and natural resources Research Chinese Academy of Sciences Beijing 100101 China Graduate University of chinese academy of sciences BeO'ing 100049 China institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China

Based on the pollen data obtained from thirty-five surface soil samples and investigated vegetation data from seven plant quadrats,the quantitative relationship between surface soil pollen and modern vegetation are studied in the longitudinal range-gorge region (LRGR) in Southwestern china.R-values (referring to pollen assemblages) are calculated with pollen percentage and plant *** coefficients of similarity between pollen and vegetation are *** results show that the pollen assemblages on surface soil of all vegetation zones can basically represent the native vegetation,but the pollen assemblages are not fully according with the *** is due to the influencing factors including pollen preservation ability,pollen production,amount of exotic pollen and pollen *** pollen representation in surface soil is different in families and *** pollen of woody plants such as Pinus,Tsuga,Alnus,Fagus and Castanopsis are over-representative,but those of Quercus,Carpinus Myrica,Elaeocarpaceae,Ericaceae,Theaceae and Llex are underrepresentative;the pollen of herbaceous plants such as Artemisia and Rubiaceae are over-representative,while those of others including Gramineae and Araliaceae are *** R-values of the same taxon pollen in different vegetation zones are different,depending on their distances from the pollen *** coefficients of the similarity between plant communities and pollen assemblages are mostly over 70%,which indicate again that the surface soil pollen and spores assemblages can represent the *** is concluded that there is a good corresponding relationship between surface pollen assemblages and native vegetation in LRGR,and it is of great significance for reconstructing the past vegetation and paleoclimate using quantitative fossil pollen data in this region.

关键词： Longitudinal range-gorge region (LRGR) Pollen assemblage Vegetation R-value Coefficient of similarity

Environmental Implication of Intensive Farming Practices on North china Plain

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chinese Journal of Population,{1. and Environment 2005年第3期3卷 11-20页

作者： Zhen Lin 1. Zhou Hailin 2.& Xie Gaodi 1.1.{1. of geographic {2. and natural resources Research, chinese academy of sciences, Beijing 1.01.1., china 2.The Administrative Center for china's Agenda 2., Beijing 1.0089, china institute of {1. {2. and natural resources Research Chinese Academy of Sciences Beijing 100101 China The Administrative Center for china’s Agenda {1. Beijing 100089 China

The current pressure on production resources of North {1. Plain, such as land and water to feed the growing population, necessitates the assessment of the sustainability of farming practices. This study focuses on the sustainability of farming practices related to groundwater and soil fertility management. The assessment is based on selected site-specific key indicators and their established threshold limits. The current farming practices in the study area are clearly unsustainable. Only about 6% of the surveyed farm households practice sustainable farming. The study stresses that farming practice, which is economically sustainable, should not be promoted at the cost of environment. Holistic strategies need to be developed and implemented that aim at balanced use of inputs, which satisfy both productivity and environmental concerns.

关键词： sustainability indicators threshold values farming practices environmental implication