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A subsurface runoff parameterization with water storage and recharge based on the Boussinesq-Storage Equation for a Land Surface Model

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Science china Earth Sciences 2006年第6期49卷 622-631页

作者： TIAN Xiangjun1,2. XIE Zhenghui1, ZHANG Shenglei1 & LIANG Miaoling1 1. LASG, Institute of Atmospheric Physics, chinese academy of Sciences, {2. 10002., china 2. graduate School of the chinese academy of Sciences, beijing 100039, china LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China graduate School of the chinese {2. of Sciences Beijing China

Subsurface runoff in a land surface model is usually parameterized as a single-valued function of total storage in a basin aquifer reservoir. This kind of parameterization is often sin-gle-valued function of storage-discharge under a steady or “quasi-steady” state, which cannot rep-resent the influence of aquifer recharge on subsurface runoff generation. In this paper, a new sub-surface runoff parameterization with water storage and recharge based on the Boussinesq-storage equation is developed. This model is validated by a subsurface flow separation algorithm for an ex-ample river basin, which shows that the new model can simulate the subsurface flow reasonably.

关键词： Zsubsurface runoff parameterization Boussinesq-storage equation waterstorage and recharge

Compositions of heavy minerals in Northeastern china sandlands and provenance analysis

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Science china Earth Sciences 2007年第11期50卷 1715-1723页

作者： XIE Jing1,2.& DING ZhongLi1 1 Institute of Geology and Geophysics, chinese academy of Sciences, {2. 10002., china 2.graduate university of chinese academy of Sciences, {2. 100049, china Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China graduate university of {2. academy of Sciences Beijing China

Sand samples deposited since the Last Glacial Maximum (LGM) from the Hulun Buir, Horqin and Otin-dag sandlands were measured for their assemblages of heavy minerals and chemical compositions of detrital garnets and tourmalines. Heavy mineral assemblages of these three sandlands consist mainly of garnet, ilmenite, epidote and minor amphibole and magnetite. Garnets consist mainly of high Mg type-A ones (58% on average), and minor type-B ones. Toumalines are mainly composed of Mg-rich and minor Fe-rich ones. Compared with those of central-southern Mongolia and central Tarim, these three sandlands are derived from the Phanerozoic rocks of the Central Asian Orogenic Belt and the Archean and Paleoprotorozoic basement rocks of the North china Craton. Our results provide direct evidence that the present-day sands may be reworked from LGM ones. Differences of heavy mineral composi-tions occur between the samples of the three sandlands and Taklimakan Desert, indicating that the material of the western arid regions contributes little to the eastern sandlands.

关键词： heavy minerals,provenance,Northeastern china,garnet,tourmaline

A SAR sidelobe suppression algorithm based on modified spatially variant apodization

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Science china(Technological Sciences) 2010年第9期53卷 2542-2551页

作者： NI Chong1,2.WANG YanFei1,XU XiangHui1,ZHOU ChangYi1 & CUI PengFei1,2.1 Institute of Electronics,chinese academy of Sciences,{2. 100190,china 2.graduate university of chinese academy of Sciences,{2. 100039,china Institute of Electronics Chinese Academy of Sciences Beijing China graduate university of {2. academy of Sciences Beijing China

The existing spatially variant apodizations (SVAs) either cannot depress the sidelobes effectively or reduce the energy of the *** improve this,a modified SVA (MSVA) is put forward in this paper,which expands the traditional filter from 3-taps to 5-taps and sets relevant parameters according to different sampling rates to get the excellent result that satisfies constrained optimization theory.A method for synthetic aperture radar (SAR) sidelobe control based on MSVA is presented,which applies MSVA to range compression and azimuth compression to control *** method which is available for any Nyquist sampling rate can both depress the sidelobes effectively and keep the energy of the mainlobe and the resolution of the *** method can reduce sidelobe levels more effectively than classical amplitude weighting while maintaining the image resolution,as demonstrated by the result of the experiment.

关键词： synthetic aperture radar sidelobe suppression resolution SVA

SHRIMP zircon U-Pb geochronology of early Mesozoic felsic igneous rocks from the southern Lancangjiang and its tectonic implications

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Science china Earth Sciences 2006年第10期49卷 1032-1042页

作者： PENG Touping1,2. WANG Yuejun1, FAN Weiming1, LIU Dunyi3, SHI Yuruo3 & MIAO Laicheng4 1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou Institute of Geochemistry, chinese academy of Sciences, Guangzhou 510640,{2. 2. graduate university of chinese academy of Sciences, beijing 100039,{2. 3. SHRIMP isotope Laboratory, chinese academy of Geological Sciences, beijing 100037,{2. 4. Institute of Geology and Geophysics, chinese academy of Sciences, beijing 10002.,{2. Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China graduate university of {2. academy of Sciences Beijing China SHRIMP isotope Laboratory Chinese Academy of Geological Sciences Beijing China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

The SHRIMP zircon U-Pb geochronology of three typical samples, including two monzo nitic granites from the Lincang batholith and a rhyolite from the Manghuai Formation are presented in the southern Lancangjiang, western Yunnan Province. The analyses of zircons for the biotite monzonitic granites from the northern (02.X-137) and southern (2.JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 2.6Pb/2.8U ages of 2.9.4 ± 3.0 Ma and 2.0.4 ± 3.6 Ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02.X-95) from the Manghuai Formation give a weighted mean 2.6Pb/2.8U age of 2.1.0 ± 5.0 Ma. These data suggest that the igneous rocks from the Lincang granitic batholith and Manghuai Formation have a similar crystallized age. In combination with other data, it is inferred that both were generated at a narrow age span (~2.0 Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 2.6Pb/2.8U apparent age of 1977±44 Ma is additionally obtained from one zircon from the biotite monzonitic granite (southern Lincang batholith), indicative of devel- opment of the early Proterozoic Yangtze basement in the region. These precisely geochronological data provide important constraints on better understanding the Paleozoic tectonic evolution of the Tethys, western Yunnan Province.

关键词： SHRIMP zircon U-Pb dating, Middle Triassic, Lincang granitic batholith, Manghuai Formation rhyolite, southern Lancangjiang.

Photodissociation/photoionization processes of chlorobromomethane induced by femtosecond laser pulses with pump-probe scheme

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chinese Science Bulletin 2008年第5期53卷 681-686页

作者： ZHANG Feng1,2. WEI ZhengRong1,2. CAO ZhenZhou1,2. ZHANG ChangHua1,2.& ZHANG Bing1,2.1 State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, chinese academy of Sciences, Wuhan 430071,{2. 2.graduate university of chinese academy of Sciences, beijing 100039,{2. State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan China graduate university of {2. academy of Sciences Beijing China

The photodissociation/photoionization processes of chlorobromomethane (CH_2.rCl) induced by fem- tosecond laser pulses have been investigated using pump-probe scheme combined with the time-of-flight mass spectra. The dominate photoproducts are observed at different delay time of the pump (400 nm) and probe (800 nm) pulses and the corresponding time-dependence of them is obtained. The results show that the decaying time of the molecule CH_2.rCl in the A-band is in the 100 fs. The decaying tendencies of the fragment ions (CH_2.l^+ and CH_2.r^+) and the parent ion (CH_2.rCl^+) are almost the same and the relative ratios of the yields of them keep constant during the delay time of 0 to 150 fs. These facts suggest that the fragment ions come from the fragmentation of the parent ions in excited electronic states. The probabilities to form CH_2.l^+ and CH_2.r^+ are obtained from the relative ratio of the ion intensity and are about 71.6% and 14.2., respectively.

关键词：毫微秒激光氯溴化甲烷激光探针光解作用光化电离作用

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, {2. 10002., china 2. Department of Atmospheric Science, Yunnan university, Kunming 650091, china 3. graduate university of the chinese academy of Sciences, {2. 100049, china Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Department of Atmospheric Science Yunnan University Kunming China graduate university of the {2. academy of Sciences Beijing 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.

Effects of cosmological constant on motion of UHECR particles

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Science china(Physics,Mechanics & Astronomy) 2005年第1期48卷 44-56页

作者： CHEN Shaoxia & CHANG Zhe Institute of High Energy Physics, chinese academy of Sciences,{2., china graduate School of chinese academy of Sciences,{2., china Institute of High Energy Physics Chinese Academy of Sciences Beijing 100039 China graduate School Chinese Academy of Sciences Beijing 100039 China

Recent astronomical observations manifest that about two-thirds of the whole energy in the Universe is contributed by a small positive cosmological constant A (> 0). Then, an asymptotically de Sitter spacetime is premised naturally. However, physics in the de Sitter spacetime is very different from that in the Minkowski spacetime. As the first step, a covariant formalism of the kinematics in the de Sitter spacetime is presented here. By solving exactly the equations of motion for a field, we obtain the dispersion relation of a free particle. It is noticed that the dispersion relation is dependent on the degree of freedom of angular momentum of the particle. We show the threshold anomaly of the ultra high energy cosmic ray disappears naturally in the framework of the de Sitter kinematics.

关键词： ultrahigh energy cosmic ray, cosmological constant, curved spacetime.

Assessing the Carrying Capacity of Tourist Resorts: An Application of Tourists’ Spatial Behavior Simulator Based on GIS and Multi-Agent System

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Wuhan university Journal of Natural Sciences 2005年第4期10卷 779-784页

作者： ZHANG Ren-jun 1,2.1. Institute of Mountain Hazards and Environment, chinese academy of Sciences, Chengdu 610041, Sichuan,{2. 2. graduated School of the chinese academy of Sciences, beijing 100039,{2. Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu Sichuan China graduated School of the chinese {2. of Sciences Beijing China

Based on the study of visitors' individual spatial behaviors, a tourists'spatial behavior simulator (TSBS) to assess the carrying capacity of tourist resorts was developed,TSBS employs GIS (Geographic Information System) to manage the spatial data,and Multi-Agent systemto simulate the actions of individual visitors. By utilizing TSBS, visitors' travel patterns such aslocation, cost, and state can be analyzed and predicted. Based on this analysis and prediction, themodel of assessing the carrying capacity of resorts is built. Our results show that TSBS will be aneffective tool to accurately assess the carrying capacity of tourist resorts.

关键词： tourist resort carrying capacity TSBS GIS Multi-Agent simulator

Properties and applications of cold supersonic gas jet

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Science china(Physics,Mechanics & Astronomy) 2006年第6期49卷 709-715页

作者： ZHANG Shaofeng1,2.MA Xinwen1,2.LIU Huiping2.LI Bin1,2.& ZHU Xiaolong1,2.1. Institute of Modern Physics,chinese academy of Sciences,Lanzhou 730000,{2. 2. graduate university of chinese academy of Sciences,beijing 100049,{2. Institute of Modern Physics Chinese Academy of Sciences Lanzhou China graduate university of {2. academy of Sciences Beijing China

By analyzing the formation mechanism of a supersonic gas jet,a set of equations which describe the atomic beam properties were established. The influence of initial temperature,initial pressure,background gas pressure and pumping speed was discussed in detail. A simulation program was developed based on the equations,and the results under different initial conditions were obtained. The results are in good agreement with the experimental data,and suggest that,in order to get much smaller transverse momentum in collision experiments,it is necessary to lower the initial temperature and the initial pressure of the supersonic gas jet,together with increasing the pumping speed. These results are very instructive for construction of a new generation of cold supersonic gas jets.

关键词： cold supersonic gas jet,zone of silence,nozzle,skimmer.