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Estimating surface evapotranspiration using combined MODIS and CBERS-02 data

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Science China(Technological Sciences) 2005年第S2期48卷 145-160页

作者： XIN Xiaozhou1,2, LIU Qinhuo1, TANG Yong1,3. TIAN Guoliang1, GU Xingfa1, LI Xiaowen1,2, ZHENG Hongsheng4.& CHEN Jiayi4.1. State Key Laboratory of Remote Sensing Science, Institute of Remote Sensing Applications, Chinese Academy of Sciences, Beijing 100101, China 2. Research Center for Remote Sensing and GIS, department of Geography, Beijing Normal {3., Beijing 100875, China 3. Graduate {3. of Chinese Academy of Sciences, Beijing 10003., China 4. department of atmospheric physics,{4., Beijing 100871, China 1. State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences 100101 Beijing China2. Research Center for Remote Sensing and GIS Department of Geography Beijing Normal University 100875 Beijing China3. Graduate University of Chinese Academy of Sciences 100039 Beijing China4. Department of Atmospheric Physics Peking University 100871 Beijing China

Spatial scale error is one of the most serious problems in the estimates of land surface heat fluxes of sensible and latent from satellite-borne data such as MODIS 1km resolution reflectance and emissive data. One of the feasible and economic ways to decrease the spatial scale error is to use high resolution land use class data together with the MODIS data. CBERS-02 data were used to produce land use class of Baiyangdian area, Hebei Province, China in the autumn of 2004. The area ratio of each class in MODIS pixel was calculated, and used to derive the heat fluxes of the mixed pixel. The results showed that the estimated heat fluxes of soil, sensible and latent have been changed remarkably after using the high resolution land class data. It could be concluded from the comparison between simulated and ground-measured fluxes as well as the theoretical analysis that high resolution land class data are useful to diminishing the scale error of heat fluxes estimated from low resolution satellite data.

关键词： surface evapotranspiration spatial scale error MODIS CBERS land class.

β-delayed proton decays near the proton drip line

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Science China(physics,Mechanics & Astronomy) 2005年第3期48卷 257-267页

作者： XU Shuwei 1 , LI Zhankui 1 , XIE Yuanxiang 1 , HUANG Wenxue 1 , SHU Nengchuan 2 , CHEN Yongshou 2 , XU Furong 3., WANG Kun 4., PAN Qiangyan 1 , WANG Xudong 1 , YU Yong 1 & XING Yebing 1 1. Institute of Modern physics, Chinese Academy of Sciences, Lanzhou 73.000, China 2. Nuclear physics {3., China Institute of Atomic Energy, Beijing 1024.3. China 3. {3. of Technical physics, peking university, Beijing 100871, China 4. Shanghai Institute for Nuclear Research, Shanghai 201800, China 1. Institute of Modern physics Chinese Academy of Sciences 730000 Lanzhou China 2. Nuclear physics department China Institute of Atomic Energy 102413 Beijing China 3. department of Technical physics Peking University 100871 Beijing China 4. Shanghai Institute for Nuclear Research 201800 Shanghai China

We briefly reviewed the experimental study on a-delayed proton decays near the proton drip line published by our group during the period of 1996―2004. namely the first observation of the a-delayed proton decays of 9 new nuclides in the rare-earth region and the new measurements of a-delayed proton decays of 5 nuclides in the mass ～90 region near the N = Z line with the aid of the “p-?” coincidence in combination with a He-jet tape transport system. In the meantime some important experimental technique details were supplemented. The experimental results, including the half -lives, spins, parities, deformations and production reaction cross sections for the 14.nuclei were summarized and compared with the current nuclear-model predictions, and then the following points were represented. (1) The experimental half-lives for 85Mo and 92Rh as well as the predicted “waiting point” nuclei 89Ru and 93.d are 5―10 times longer than the theoretical predictions given by M?ller et al. using a macroscopic-microscopic model. It considerably influences the predictions of the abundances of the nuclides produced in the rp-process. (2) The current-model predictions are not consistent with the experimental assignments of the spins and parities for the proton drip-line nuclei 14.Ho and 128Pm. However, the nuclear potential energy surface (PES) calculated by using a Woods- Saxon-Strutinsky method reproduced the experimental results. (3. The Alice code overestimated the production reaction cross sections of the studied 9 rare-earth nuclei by one order of magnitude or two, while HIVAP code overestimated them by one order of magnitude approximately.

关键词： proton drip line, β-delayed proton decay, He-jet tape transport system, "p-γ" coincidence, spin, parity, deformation, production reaction cross section.

Electronic structure and magnetism of R(Fe,Si)_(12) (R=Y,Nd)

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Science China(physics,Mechanics & Astronomy) 2006年第2期49卷 195-202页

作者： SUN Guang’ai1, CHEN Bo1, DU Honglin2, FAN Zhijian1, GAO Tao3.& QI Xinhua3.. Institute of Nuclear physics and Chemistry, China Academy of Engineering physics, Mianyang 621900, China 2. department of physics,{4., Beijing 100871, China 3. Institute of Atomic and Molecular physics, Sichuan university, Chengdu 610065, China 1. Institute of Nuclear physics and Chemistry China Academy of Engineering Physics Mianyang 621900 China 2. department of physics Peking university Beijing 100871 China 3. Institute of Atomic and Molecular physics Sichuan University Chengdu 610065 China

The newly developed full-potential linearized augmented plane wave (LAPW) and local orbitals (lo) based on standard APW methods are briefly introduced, and the structure and magnetic properties of R(Fe, Si)12 compounds (R = Y, Nd) are calculated using the method. The distribution of Si at different sites is analyzed based on total energy of one crystal unit with structure having been optimized. The characters of magnetic mo-ments, total density of states (TDOS) and partial density of states (PDOS) for different crystal sites Si occupies are obtained and analyzed. The results show that the total mag-netic moments of RFe10Si2 (R = Y, Nd) are larger than those of RFe10M2 (M = Ti, V, Cr, Mn, Mo and W) and the hybridization mechanism is seen as follows. Si(8j) reduce the mag-netic moments of Fe at three sites, however, Si(8f) mainly reduce the magnetic moments of Fe(8i) and Fe(8j) atoms. The Curie temperature is markedly enhanced by the introduc-tion of Si atoms according to spin fluctuation of DOS at Fermi level.

关键词： (L)APW+lo method R(Fe Si)12(R = Y Nd) magnetic moment Density of state.

The onset and advance of the Asian summer monsoon

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Science Bulletin 2006年第1期51卷 80-88页

作者： Lü Junmei1,2,4. ZHANG Qingyun1, TAO Shiyan1 & JU Jianhua3.1. State Key Laboratory of Numerical Modeling for atmospheric Sci- ences and Geophysical Fluid Dynamics, Institute of atmospheric {3., Chinese Academy of Sciences, Beijing 100029, China 2. {3. of atmospheric Sciences, Yunnan university, Kunming 650091, China 3. China Meteorological Administration Training Centre, Beijing 100081, China 4. Graduate School of Chinese Academy of Sciences, Beijing 10003., China State Key Laboratory of Numerical Modeling for atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China department of atmospheric Sciences Yunnan University Kunming 650091 China Graduate School of Chinese Academy of Sciences Beijing 100039 China China Meteorological Administration Training Centre Beijing 100081 China

Based on the daily outgoing longwave radiation (OLR) data from National Oceanic and At- mospheric Administration (NOAA) satellites, the Cli- mate Prediction Center’s merged analysis of pre- cipitation (CMAP) data and the National Centers for Environmental Prediction/National Center for At- mospheric Research (NCEP/NCAR) reanalysis dataset, the mean intraseasonal variability of the Asian summer monsoon (ASM) is investigated by using power spectrum analysis, band-pass filter, and diagnostic analyses. The processes of the onset and advance of monsoon over the southern part of Indo- china Peninsula, the east coast of Bay of Bengal, the South China Sea and the Indian subcontinent are explored. It is found that there is an abrupt change in OLR, precipitation and zonal wind during the onset and advance of the ASM. It is also indicated that the southern part of Indochina Peninsula and the adja- cent Andaman Sea is the region where the earliest onset of the ASM occurs in the 2nd pentad of May.

关键词： Asian summer monsoon intraseasonal variability onset advance.

Experimental measurement of growth patterns on fossil corals:Secular variation in ancient Earth-Sun distances

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Chinese Science Bulletin 2010年第35期55卷 4010-4017页

作者： ZHANG WeiJia1,3.4.LI ZhengBin2,3.& LEI Yang1 1 department of physics,{3. {3.,Beijing 100871,China 2 department of Electrical Engineering and Computer Science,{3. {3.,Beijing 100871,China 3.State Key Laboratory of Advanced Optical Communication Systems & Networks,{3. {3.,Beijing 100871,China 4.Committee of Yuanpei Honors Program,{3. {3.,Beijing 100871,China department of physics Peking University Beijing 100871 China State Key Laboratory of Advanced Optical Communication Systems & Networks Peking University Beijing 100871 China Committee of Yuanpei Honors Program Peking University Beijing 100871 China department of Electrical Engineering and Computer Science Peking University Beijing 100871 China

In recent years,much attention has been given to the increase in the Earth-Sun distance,with the modern rate reported as 5-15 m/cy on the basis of astronomical ***,traditional methods cannot measure the ancient leaving rates,so a myriad of research attempting to provide explanations were met with unmatched *** this paper we consider that the growth patterns on fossils could reflect the ancient Earth-Sun *** mechanical analysis of both the Earth-Sun and Earth-Moon systems,these patterns confirmed an increase in the Earth-Sun *** a large number of well-preserved specimens and new technology available,both the modern and ancient leaving rates could be measured with high precision,and it was found that the Earth has been leaving the Sun over the past 0.53.billion *** Earth's semi-major axis was 14. million kilometers at the beginning of the Phanerozoic Eon,equating to 97.6% of its current *** modern leaving rates are 5-14.m/cy,whereas the ancient rates were much *** results indicate a special expansion with an average expansion coefficient of 0.57H0 and deceleration in the form of Hubble *** the basis of experimental results,the Earth's semi-major axis could be represented by a simple formula that matches fossil measurements.

关键词：地球太阳古代距离生长模式实验石珊瑚量化

Response synchronization: New progress in brain-visual information processing

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Chinese Science Bulletin 1999年第16期44卷 1447-1458页

作者： ZHAO Songnian, XIONG Xiaoyun, YAO Guozheng and GUO Aike1. State Key Laboratory of atmospheric Boundary Layer physics and atmospheric Chemistry , Institute of atmospheric physics , Chinese Academy of Sciences , Beijing 100029, China 2. Commission of the National Natural Science Foundation of China , Beijing 100083. China 3. The Center of Information Science , peking university, Beijing 100871, China 4. Open Laboratory of Visual Information Processing , Institute of Biophysics , Chinese Academy of Sciences , Beijing 100101, China State Key Laboratory of atmospheric Boundary Layer physics and atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Commission of the National Natural Science Foundation of China Beijing China The Center of Information Science Peking University Beijing China Open Laboratory of Visual Information Processing Institute of Biophysics Chinese Academy of Sciences Beijing China

Studies on brain-vision have entered a new stage, after the stimulus-induced y synchronized oscillation of neuron group activities have been discovered in cat primary visual cortex. Naturally, how to understand the visual system became a very important methodological problem. From aspects such as information processing, nonlinear dynamics and neuronal network, some primary problems in vision studies have been deeply discussed, which are

关键词： neuron group (neural population) synchro-oscillation computational theory of vision response synchroniza-tion.

A general information theoretical proof for the second law of thermodynamics

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Science China(physics,Mechanics & Astronomy) 2008年第7期51卷 813-816页

作者： ZHANG QiRen department of Technical physics, peking university, Beijing 100871, China 1. department of Technical physics Peking University Beijing 100871 China

It is shown that the conservation and the non-additivity of the information, together with the additivity of the entropy, make the entropy increase in an isolated system. The collapse of the entangled quantum state offers an example of the information non-additivity. Nevertheless, the non-additivity of information is also true in other fields in which the interaction information is important. Examples are classical statistical mechanics, social statistics and financial processes. The second law of thermodynamics is thus proven in its most general form. It is exactly true not only in quantum and classical physics but also in other processes in which the information is conservative and non-additive.

关键词： information conservation non-additivity of information entropy increase

Local and non-local sources of airborne particulate pollution at Beijing——The ratio of Mg/Al as an element tracer for estimating the contributions of mineral aerosols from outside Beijing

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Science China Chemistry 2005年第3期48卷 253-264页

作者： HAN Lihui1, ZHUANG Guoshun1,2,3. SUN Yele1 & WANG Zifa3.1. The Center for atmospheric Environmental Study, department of Chemistry, Beijing Normal university, Beijing 100875, China 2. Center for atmospheric Chemistry Study, department of Environmental Science & Engineering, Fudan university, Shanghai 2004.3. China 3. LAPC/NZC, Institute of atmospheric physics, CAS, Beijing 100029, China 1. The Center for atmospheric Environmental Study Department of Chemistry Beijing Normal University 100875 Beijing China 2. Center for atmospheric Chemistry Study Department of Environmental Science & Engineering Fudan University 200433 Shanghai China 3. Institute of atmospheric physics CAS LAPC/NZC 100029 Beijing China

A new element tracer technique has firstly been established to estimate the contri-butions of mineral aerosols from both inside and outside Beijing. The ratio of Mg/Al in aerosol is a feasible element tracer to distinguish between the sources of inside and outside Beijing. Mineral aerosol, inorganic pollution aerosol mainly as sulfate and nitrate, and organic aerosol are the major components of airborne particulates in Beijing, of which mineral aerosol accounted for 3.%―67% of total suspended particles （TSP）, 10%―70% of fine particles （PM2.5）, and as high as 74. and 90% of TSP and PM2.5, respectively, in dust storm. The sources from outside Beijing contributed 62% （3.%―86%） of the total mineral aerosols in TSP, 69% （52%―90%） in PM10, and 76% （59%―93.） in PM2.5 in spring, and 69% （52%―83.）, 79% （52%―93.）, and 4.% （7%―79%） in TSP, PM10, and PM2.5, respectively, in winter, while only20% in summer and autumn. The sources from outside Beijing contributed as high as 97% during dust storm and were the dominant source of airborne particulates in Beijing. The contributions from outside Bei-jing in spring and winter are higher than those in summer, indicating clearly that it was related to the various meteorological factors.

关键词： mineral aerosol local sources non-local sources dust storm re-suspended dust element tracer technique.

Interannual variability of Antarctic Oscillation and its influence on East Asian climate during boreal winter and spring

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Science China Earth Sciences 2006年第5期49卷 554-560页

作者： FAN Ke1,2,3.& WANG Huijun2 1. Nansen-Zhu International Research Center, Institute of atmospheric physics, Chinese Academy of Sciences, Beijing 100029, China 2. department of atmospheric Science, Yunnan {4., Kunming 650091, China 3. Graduate {4. of the Chinese Academy of Sciences, Beijing 10004., China 1. Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. department of atmospheric Science Yunnan University Kunming 650091 China 3. Graduate university of the Chinese Academy of Sciences Beijing 100049 China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific Ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.