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Inertial theory of the mean Hadley circulation under the condition of nonstatic equilibrium

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Science china Earth sciences 2006年第5期49卷 546-553页

作者： CHAO Jiping1 & LIU Fei2,3 1. National Marine Environmental Forecasting Center, beijing 100081, china 2. Key Laboratory Regional Climate-Environment for Temperate East Asia, Institute of Atmospheric Physics, chinese academy of sciences, beijing 100029, china 3. graduate university of chinese academy of sciences, beijing 100049, china National Marine Environmental Forecasting Center Key Laboratory Regional Climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences graduate university of chinese academy of sciences

Tropical atmosphere is divided into two layers, the layer near the ground is the planet boundary layer, where the motion is linear, if the radiation equilibrium temperature is given at the top of the boundary layer, the vertical motion there can be obtained. It is the non-viscous ideal atmos- pheric layer above the boundary one, where the motion is nonlinear. After getting the conservation laws of angular momentum, potential temperature and potential vortex, the inertial theory of the Hadley circulation driven by the vertical motion of the boundary layer is established, followed by sev- eral examples of its application.

关键词： Hadley circulation, inertial theory, conservation laws of angular momentum, potential temperature and potential vortex.

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 Geographic sciences 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

Vertical adaptive radiation in ocean Prochlorococcus:Evolutionary implications of the Ch1 b/a ratio from molecular evidence

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Progress in Natural Science:Materials International 2009年第11期19卷 1561-1568页

作者： Song Qin~(a,*),Yinchu Wang~(a,b) a Yantai Institute of Coastal Zone Research for Sustainable Development,chinese academy of sciences,Yantai 264003,china b graduate university of chinese academy of sciences,beijing 100049,china Yantai Institute of Coastal Zone Research for Sustainable Development Chinese Academy of Sciences Yantai 264003 China graduate university of chinese academy of sciences Beijing 100049 China

Prochlorococcus is a marine cyanobacterium of global *** ecotypes are adapted to either high-light(HL) or low-light (LL) *** ratio between chlorophyll(Chl) a and b is a distinguishing characteristic of these two ***,how this ratio evolved in Prochlorococcus during this ecotype differentiation remains *** analyses reveal that the ancestor of Prochlorococcus was typically low-light *** LL ecotype showed a stagnant evolution,and the HL ecotype was recently *** was an adaptive radiation after directional evolution in the Chl bla ratio *** in chlorophyllide a oxygenase(CAO) and positive selection on Clp protease contributed to the directional evolution of *** recombinant fragments of CAO were correlated with a large group of shared coevolving *** of positive selection was found in both subunits of *** bla ratio evolution,as annotated by molecular evidence,appears to be among the crucial reasons that explain how Prochlorococcus has become the dominant photosynthetic organism in the ocean.

关键词： Prochlorococcus Ch1 b/a ratio Adaptive evolution Trait evolution Ecotype differentiation

Joint source channel VL coding/decoding for deep space communication networks based on a space trellis

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Science china(Information sciences) 2011年第9期54卷 1883-1894页

作者： WU WeiRen 1,TU Juan 2,TU GuoFang 1,GAO ShaoShuai 1 & ZHANG Can 1,3 1 School of Information Science and Engineering,graduate university of chinese academy of sciences,beijing 100049,china 2 beijing Institute of Electronic System Engineering,china Aerospace Science & Industry Corp.,beijing 100854,china 3 State Key Laboratory of Information Security,graduate university of chinese academy of Science,beijing 100049,china School of Information Science and Engineering Graduate University of Chinese Academy of Sciences beijing Institute of Electronic System Engineering China Aerospace Science & Industry Corp

This paper presents joint source channel variable length (VL) coding/decoding based on a space *** constructing a joint decoding plane trellis,better decoding performance can be achieved than by using the bit-level decoding ***,the plane trellis is complicated,which results in high decoding complexity for decoding VL turbo *** solve this problem,we construct a space trellis and design a low-complexity joint decoding algorithm with a variable length symbol-a posteriori probability (VLS-APP) algorithm in resource constrained deep space communication *** results show that the proposed approach reduces the decoding complexity by 10% compared with the plane trellis,and the gain of Eb/N0 is about 0.2 dB at SER=***,it provides substantial error protection for variable-length encoded image data.

关键词： joint coding/decoding VL turbo codes space trellis VLS-APP

Responses of soil respiration in non-growing seasons to environmental factors in a maize agroecosystem,Northeast china

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chinese Science Bulletin 2010年第24期55卷 2723-2730页

作者： LI RongPing1,2,3, ZHOU GuangSheng1,4 & WANG Yu1,3 1 State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, chinese academy of sciences, beijing 100093, china 2 Institute of Atmospheric Environment, china Meteorological Administration, Shenyang 110016, china 3.graduate university of chinese academy of sciences, beijing 100049, china 4 chinese academy of Meteorological sciences, beijing 100081, china State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China Institute of Atmospheric Environment China Meteorological Administration Shenyang 110016 China graduate university of chinese academy of sciences Beijing 100049 China chinese academy of Meteorological sciences Beijing 100081 China

Based on continuous three-year measurements (from 2004 to 2007) of eddy covariance and related environmental factors, environmental controls on variation in soil respiration (Rs) during non-growing season were explored in a maize agroecosystem in Northeast china. Our results indicated that during non-growing seasons, daily Rs was 1.08-4.08 g CO2 m-2 d-1, and the lowest occurred in late November. The average Rs of non-growing season was 456.06 ± 20.01 g CO2 m-2, accounting for 11% of the gross primary production (GPP) of the growing season. Additionally, at monthly scale, the lowest value of Rs appeared in January or February. From the beginning to the end of non-growing season, daily Rs tended to decrease first, and then increase to the highest. There was a significant quadratic curve relationship between Rs and soil temperature at 10 cm depth when soil temperature was more than 0°C (P38%-70%. When soil water content was more than 0.1 m3 m-3, soil moisture at 10 cm depth was significantly parabolically correlated with Rs (P3%-79%. Meanwhile, the standard error of regression estimation between the values of prediction and observation for Rs could reach 2.7%-11.8%. Rs in non-growing season can account for 22.4% of Rs in growing season, indicating that it plays a critical role in assessing the carbon budget in maize agroecosystem, Northeast china.

关键词：中国东北地区农田生态系统生长季节土壤呼吸环境因素玉米土壤含水量反应

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, china 2. graduate university of chinese academy of sciences, beijing 100039, china 3. SHRIMP isotope Laboratory, chinese academy of Geological sciences, beijing 100037, china 4. Institute of Geology and Geophysics, chinese academy of sciences, beijing 100029, china Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China graduate university of chinese 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 (02DX-137) and southern (20JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 206Pb/238U ages of 229.4 ± 3.0 Ma and 230.4 ± 3.6 Ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02DX-95) from the Manghuai Formation give a weighted mean 206Pb/238U age of 231.0 ± 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 (~230 Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 206Pb/238U 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.

Relationship between precipitation and the infiltration depth over the middle and lower reaches of the Yellow River and Yangtze-Huaihe River Valley

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Progress in Natural Science:Materials International 2008年第9期18卷 1123-1128页

作者： Zhixin Hao a, Jingyun Zheng a, Quansheng Gea,, Xifeng Guoa,b a Institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, 11A, Datun Road Anwai, Chaoyang District, beijing 100101, china b graduate university of chinese academy of sciences, beijing 100049, china Institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences 11A Datun Road Anwai Chaoyang District Beijing 100101 China graduate university of chinese academy of sciences Beijing 100049 China

The purpose of the paper is to extract and make the best use of rainfall information contained in the chinese historical archives of Qing Dynasty, and reconstruct the precipitation series during *** study followed the Yu-Fen-Cun (rainfall infiltration depth) observation method in Qing Dynasty, to conduct soil infiltration experiment under the natural rainfall conditions during *** related parameters, such as precipitation, intensity, initial soil moisture content and infiltration depth have been measured at 10 stations (east of 105°E, 30°-40°N) with representative climatic conditions and soil physical texture in the middle and lower reaches of the Yellow River and Yangtze-Huaihe River *** statistical results indicate that precipitation is the primary infiuencing factor to infiltration depth and is positively correlated with the infiltration ***, the efiects of every factor on infiltration depth are significantly difierent between the middle and lower reaches of the Yellow River and Yangtze-Huaihe River ***, the relationship equations of precipitation and infiltration depth are established for each site, most of which can pass over 60% of the variance explanations and provide quantitative models to reconstruct the precipitation series using Yu-Fen-Cun records in Qing Dynasty.

关键词： Middle and lower reaches of the Yellow River and Yangtze-Huaihe River Valley Precipitation Infiltration depth Yu-Fen-Cun Climate reconstruction

Validating global hydrological models by ground and space gravimetry

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chinese Science Bulletin 2009年第9期54卷 1534-1542页

作者： ZHOU JiangCun1,2,3, SUN HePing1,2 & XU JianQiao1,2 1 Institute of Geodesy and Geophysics, chinese academy of sciences, Wuhan 430077, china 2 Key Laboratory of dynamic geodesy, chinese academy of sciences, Wuhan 430077, china 3.graduate university of chinese academy of sciences, beijing 100049, china Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China Key Laboratory of dynamic geodesy Chinese Academy of Sciences Wuhan 430077 China graduate university of chinese academy of sciences Beijing 100049 China

The long-term continuous gravity observations obtained by the superconducting gravimeters (SG) at seven globally-distributed stations are comprehensively analyzed. After removing the signals related to the Earth's tides and variations in the Earth's rotation, the gravity residuals are used to describe the seasonal fluctuations in gravity field. Meanwhile, the gravity changes due to the air pressure loading are theoretically modeled from the measurements of the local air pressure, and those due to land water and nontidal ocean loading are also calculated according to the corresponding numerical models. The numerical results show that the gravity changes due to both the air pressure and land water loading are as large as 100×10-9 m s-2 in magnitude, and about 10×10-9 m s-2 for those due to the nontidal ocean loading in the coastal area. On the other hand, the monthly-averaged gravity variations over the area surrounding the stations are derived from the spherical harmonic coefficients of the GRACE-recovered gravity fields, by using Gaussian smoothing technique in which the radius is set to be 600 km. Com-pared the land water induced gravity variations, the SG observations after removal of tides, polar mo-tion effects, air pressure and nontidal ocean loading effects and the GRACE-derived gravity variations with each other, it is inferred that both the ground- and space-based gravity observations can effec-tively detect the seasonal gravity variations with a magnitude of 100×10-9 m s-2 induced by the land water loading. This implies that high precision gravimetry is an effective technique to validate the re-liabilities of the hydrological models.

关键词：重力测量水文模型模型验证和空间地面重力变化季节性波动空气压力

Threshold quantum secure direct communication without entanglement

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Science china(Physics,Mechanics & Astronomy) 2008年第2期51卷 176-183页

作者： YANG YuGuang1,3 & WEN QiaoYan2 1 College of Computer Science and Technology, beijing university of Technology, beijing 100022, china 2 School of Science, beijing university of Posts and Telecommunications, beijing 100876, china 3 State Key Laboratory of Information Security (graduate School of chinese academy of sciences), beijing 100049, china College of Computer Science and Technology Beijing University of Technology Beijing China State Key Laboratory of Information Security (graduate School of chinese academy of sciences) Beijing China School of Science Beijing University of Posts and Telecommunications Beijing China

For the first time, a threshold quantum secure direct communication (TQSDC) scheme is presented. Similar to the classical Shamir's secret sharing scheme, the sender makes n shares, S1, …, Sn of secret key K and each receiver keeps a share secretly. If the sender wants to send a secret message M to the receivers, he en-codes the information of K and M on a single photon sequence and sends it to one of the receivers. According to the secret shares, the t receivers sequentially per-form the corresponding unitary operations on the single photon sequence and ob-tain the secret message M. The shared shares may be reusable if it can be judged that there is no eavesdropper in line. We discuss that our protocol is feasible with current technology.

关键词： quantum secure direct communication threshold secure direct communication quantum secret sharing