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Estimation of annual actual evapotranspiration from nonsaturated land surfaces with conventional meteorological data

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Science china earth {2. 2004年第3期47卷 239-246页

作者： QIU Xinfa1, ZENG Yan2. MIAO Qilong1 & YU Qiang2.1. Department of Geography, nanjing Institute of Meteorology, nanjing 2.0044, {2. 2. Institute of Geographic sciences and Natural Resources Research, Chinese Academy of sciences, Beijing 100101, {2. Department of Geography Nanjing Institute of Meteorology Nanjing 210044 China Inst. of Geogr. Sci./Nat. Rsrc. Res. Chinese Academy of Sciences Beijing 100101 China

Views diverge greatly on the relationship between actual evapotranspiration (AE) and potential evapotranspiration (PE). Penman showed that AE is determined in intensity by PE and changes proportionally as a function of PE. In contrast, Bouchet indicated that AE deter-mines PE and varies inversely with PE. Based on nearly 30 years data from 432.weather stations and 512.hydrological stations in china, the two different theories, Penman抯 assumption and Bouchet抯 complementary relationship between AE and PE, were tested on nine river basins. With data integration technique, the complementary relationship between AE and PE was dis-played entirely. A general model to estimate the actual evapotranspiration from nonsaturated surfaces by routine meteorological observations has been established on the basis of thorough analysis of the concept of PE. The results show that the calculations are all in error control of <10%, except for a few years over the Yellow River Basin.

关键词： complementary relationship of evapotranspiration, potential evapotranspiration, actual evapotranspiration.

An elastic-plastic analysis of short-leg shear wall structures during earthquakes

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earthquake Engineering and Engineering Vibration 2012年第4期11卷 525-540页

作者： Ding Jianguo Zhu Ying School of sciences Nanjing University of Science and Technology Huaxin Consulting CO. Ltd

Short-leg shear wall structures are a new form of building structure that combine the merits of both frame and shear wall structures. Its architectural features, structure bearing and engineering cost are reasonable. To analyze the elastic-plastic response of a short-leg shear wall structure during an earthquake, this study modified the multiple-vertical-rod element model of the shear wall, considered the shear lag effect and proposed a multiple-vertical-rod element coupling beam model with a new local stiffness domain. Based on the principle of minimum potential energy and the variational principle, the stiffness matrixes of a short-leg shear wall and a coupling beam are derived in this study. Furthermore, the bending shear correlation for the analysis of different parameters to describe the structure, such as the beam height to span ratio, short-leg shear wall height to thickness ratio, and steel ratio are introduced. The results show that the height to span ratio directly affects the structural integrity; and the short-leg shear wall height to thickness ratio should be limited to a range of approximately 6.0 to 7.0. The design of short-leg shear walls should be in accordance with the ＂strong wall and weak beam＂ principle.

关键词： short-leg shear wall multiple-vertical-rod element model shear lag effect bending shear correlationcoefficient coupling beam stiffness matrix elastic-plastic analysis

Nitrogen isotopic geochemical characteristics of crude oils in several basins of china

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Science china earth {2. 2005年第8期48卷 1211-1219页

作者： CHEN Chuanping1,2. MEI Bowen1 & CAO Yacheng3 1. Jianghan Petroleum university, Jingzhou 434100, china 2. Huazhong university of Science and Technology, Wuhan 430047, china 3. nanjing Institute of Soil Science, Chinese Academy of sciences, nanjing 2.0008, china Jianghan Petroleum university Jingzhou China Huazhong university of Science and Technology Wuhan China nanjing Institute of Soil Science Chinese Academy of Sciences Nanjing China

Nitrogen isotopic ratios of crude oils with different physical and chemical properties in several basins of china have been measured and their geochemistry has been studied ele-mentally combined with molecular organic geochemistry methods. The data indicate that δ 15N is in the range of ?6‰-2.‰. They vary with the oils in different sedimentary types of basins. The oils forming in the limnic environment have lower δ 15N with the value of about 1‰-5‰ whereas the oils in saline or semi-saline environment have higher δ 15N, with most samples being above 10‰ and some exceeding 17‰. The average nitrogen isotopic ratio of oils from the Ordovician formation in the Tarim Basin is the lowest, with most samples having δ 15N below zero, which reflects possibly the characteristic of the oils originating mainly from the organic matter formed in marine carbonate sedimentary environment. The δ 15N distribution can be altered by fractionation. It increases obviously because of biodegradation and decreases during hydrocarbon migration. However, the effect of nitrogen isotopic fractionation in the short distance migration is uncon-spicuous.

关键词： nitrogen isotope, crude oil, sedimentary environment, isotopic fractionation, china.

Almandine megacrysts from Yingfengling Cenozoic basalt in Leizhou Peninsula and their parental magma origin

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Chinese Science Bulletin 2001年第14期46卷 1215-1219页

作者： YU Jinhai & S. Y. O’Reilly1. National Key Laboratory of Metallogenic Mechanism of Endogenetic Deposits, Department of earth sciences,{2., nanjing 2.0093. china 2. National Key Center of GEMOC, Department of earth and Planetary sciences, Macquarie university, North Ryde, NSW 2.09, Australia National Key Laboratory of Metallogenic Mechanism of Endogenetic Deposits Department of Earth Sciences Nanjing University Nanjing China National Key Center of GEMOC Department of Earth and Planetary Sciences Macquarie University North Ryde Australia

The garnet megacrysts from Yingfengling basalts are characterlzed by high FeO (>2.%), CaO (7.02. -8.16%) and low MgO (5.88%-10.87%). Significant composition variations are observed in these megacrysts, of which Ni, V, Sc, Co, and HREE are positively correlated with their Mg# and Zr, Hf, Ga, Y, Sr, Nb, Zn and LREE-MREE are negatively correlated with Mg#. Megacryst parent magma is a highly evolved residual melt with strongl depletion in Ti, Sr, Hf, Nb and HREE. This parental magma was generated by more than 60% of crystallization fractionation of clinopyroxene, garnet, plagioclase and ilmenite from quartz tholeiitic magma. It has not erupted to the surface, but stayed at the upper mantle and formed the megacrystic cumulate. Megacrysts and their host basalt are in disequilibrium.

关键词： almandine megacryst geochemistry LAM-ICPMS Lei-zhou Peninsula.

The history of crustal uplift and metamorphic evolution of Panzhihua-Xichang micro-palaeoland, SW china:Constraints on Sm-Nd, ^(40)Ar/^(39)Ar and FT ages of granulites

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Science china earth {2. 2004年第8期47卷 689-703页

作者： XU Shijin1, LIU Wenzhong1, WANG Rucheng1, YU Hangbo1, LI Daming2. WAN Jinglin2.& FANG Zhong1 1. Department of earth sciences and State Key Laboratory for Mineral Deposits Research,{2., nanjing 2.0093. china 2. Institute of Geology, china Seismological Bureau, Beijing 10002., china Department of earth sciences and State Key Laboratory for Mineral Deposits Research Nanjing University Nanjing China Institute of Geology China Seismological Bureau Beijing China

Panzhihua-Xichang (Panxi) micro-palaeoland is the oldest terrane on the western margin of the Yangtze Block. Some intermediate-basic granulites are considered to be the crys-talline basement of lower crust in the terrane. Granulite-facies metamorphism of the granulites was developed in the period from 1186 Ma to 112. Ma. The origin of granulites was related to the collision orogenic process occurring when the micro-palaeolands merged to form the Rodinia Supercontinent. Amphibolite-facies retrogressive metamorphism of granulites took place in the period from 877 Ma to 82. Ma. This period was consistent with the breakup time of the Rodinia Supercontinent. 40Ar/39Ar ages and fission track (FT) ages of granulites in the Panxi mi-cro-palaeoland show that the vertical movement history of crustal rocks was a slow uplift process of the rigid terrane in the time from Neoproterozoic to Mesozoic. The subduction of India Plate towards Euroasia Plate resulted in the rapid uplift of the Qinghai-Tibetan Block in Cenozoic. Meanwhile, the Qinghai-Tibetan Block moved towards east. Consequently the Panxi terrane was uplifted rapidly. As a result of the collision orogeny between the Qinghai-Tibetan Block and the Panxi terrane, the granulite-facies crystalline basement in this region was exhumed and exposed to the surface.

关键词： granulite,isotope geochronology,crustal uplift movement,Panzhihua-Xichang region,western margin of Yangtze Block.

Reducing component estimation for varying coefficient models with longitudinal data

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Science china Mathematics 2008年第2期51卷 250-272页

作者： TANG QingGuo~(1,2.) WANG JinDe~2.1 Institute of sciences,People’s Liberation Army university of Science and Technology,{2. 2.0007,china 2.Department of Mathematics,{2. university,{2. 2.0093.china Institute of sciences People’s Liberation Army University of Science and Technology Nanjing China Department of Mathematics Nanjing University Nanjing China

Varying-coefficient models with longitudinal observations are very useful in epidemiology and some other practical *** this paper,a reducing component procedure is proposed for es- timating the unknown functions and their derivatives in very general models,in which the unknown coefficient functions admit different or the same degrees of smoothness and the covariates can be time- *** asymptotic properties of the estimators,such as consistency,rate of convergence and asymptotic distribution,are *** asymptotic results show that the asymptotic variance of the reducing component estimators is smaller than that of the existing estimators when the coefficient functions admit different degrees of *** sample properties of our procedures are studied through Monte Carlo simulations.

关键词： varying coefficient model longitudinal data nonparametric estimation reducing component estimators asymptotic normality 62.07

Ability of Agrogyron elongatum to accumulate the single metal of cadmium, copper, nickel and lead and root exudation of organic acids

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Journal of Environmental sciences 2001年第3期13卷 368-375页

作者： YANG Hong 1, Jongathan W.C.Wong 2. YANG Zhi min\+1, ZHOU Li xiang 1(1. College of Science, nanjing Agricultural university, nanjing\ 2.0095, china. 2. Department of Biology, Hong Kong Baptist university, china) 南京农业大学江苏南京 210095 香港浸会大学香港

Agrogyron elongatum were grown in nutrient solution containing moderate to high amounts of separate heavy metal of Cd, Cu, Ni and Ph in a greenhouse for a 9 - day. Cd, Cu, Ni and Ph generally led to decrease in the elongation of roots although the length of seedlings exposed to Cd and Ph at 0.05 and 0.5 mg/L showed to be slightly greater than that of controls. Of the four metals in the experiment, Ph was absorbed and accumulated to the highest level, with the concentrations of 92.54 mg/kg dry weight (DW) in roots and 11683 mg/kg DW in shoots. Cd was moderately accumulated in Agrogyron elongatum, but the maximum bioaccumulation coefficients (BCs) for roots and shoots were observed. The patterns for Cu and Ni uptake and distribution in plants differed from those of Ph and Cd, as it was showed that the shoot accumulation of Cu and Ni was significantly higher than in roots. A. elongation had the highest Ni concentration in shoots (302.1 mg/kg DW) at the external concentration of 2.0 mg/L. Cu ranked second, with a shoot concentration of 12.30 mg/kg DW when 50 mg/L Cu in solution was applied. For the four trace elements tested, the highest concentrations in shoots decreased by the order of Ni > Cu > Ph > Cd (mg/kg DW), and those in roots were Ph > Cd > Ni > Cu (mg/kg DW). Malic, oxalic and citric acids exuded by roots exposed to 1 and 50 mg/L of the metals were detected. Release of organic acids from plants significantly differed among the metal treatments. Cu was most effectively in inducing root exudation of the three types of organic acids. Cd, and Ni were also the inducers of secretion of malic and oxalic acids. With reference of Pb, a small amounts of malic and oxalic acids were detected in the root exudates, but few quantities, of citric acid were. found. However, no correlation between alternations in root exudation of organic acids and metal accumulation could be established.

关键词： heavy metal organic acid Agrogyron elongation hyperaccumulation

Characteristics of fMRI BOLD signal and its neurophysiological mechanism

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Progress in Natural Science:Materials International 2007年第6期17卷 630-638页

作者： Zhao Xiaohu1,2. Wu Yigen3 and Guo Shengli3(1. College of Life sciences, Zhejiang university, Hangzhou 310058, {2. 2. Imaging Department of Tongji Hospital of Tongji university, Shanghai 2.0065, {2. 3. College of Mathematics and Physics, nanjing university of Information Science and Technology, nanjing 2.0044, {2.) College of Life sciences Zhejiang University Hangzhou 310058 China Imaging Department Tongji Hospital Tongji University Shanghai 200065 China College of Mathematics and Physics Nanjing University of Information Science and Technology Nanjing 210044 China

The functional magnetic resonance imaging (fMRI) based on blood oxygen level dependent (BOLD) contrast has emerged as one of the most potent noninvasive tools for mapping brain function and has been widely used to explore physiological, pathological changes and mental activity in the brain. Exploring the nature and property of BOLD signal has recently attracted more attentions. Despite that great progress has been made in investigation of the characteristics and neurophysiological basis, the exact nature of BOLD signal remains unclear. In this paper we discuss the characteristics of BOLD signals, the nonlinear BOLD response to external stimuli and the relation between BOLD signals and neural electrophysiological recordings. Furthermore, we develop our new opinions regarding nonlinear BOLD response and make some perspectives on future study.

关键词： functional magnetic resonance imaging blood oxygen level dependent nonlinear response neural electrophysiological activity.

Paleoceanographic evolution recorded in the northern South china Sea since 4 Ma

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Science china earth {2. 2005年第12期48卷 2166-2173页

作者： HUANG Baoqi1,2. JIAN Zhimin2.& WANG Pinxian2.1. School of earth and Space sciences, Peking {2., Beijing 100871, china 2. Laboratory of Marine Geology, Tongji {2., Shanghai 2.0092. china School of earth and Space sciences Peking University Beijing China Laboratory of Marine Geology Tongji University Shanghai China

Upper water structure over the last 4 million years in the northern South china Sea (SCS) was reconstructed by sea surface temperature (SST) and primary productivity estimated by changes in the abundance of planktonic foraminifer, planktonic foraminifer transfer function, and the accumulation rate of benthic foraminifera. Results of SST and primary productivity show that SST gradually decreased since 4 Ma, but differential seasonal temperature and primary productivity increased in steps mainly at about 3.1, 2.7, 2.1, 1.6, 0.9 and 0.5 Ma. Comparison with tectonics and orbital variations indicates that phased rising of the Tibet since 3.6 Ma, closing of Panama and Indonesian seaways, and orbital changes were responsible for the changes of upper water structure in the SCS, respectively.

关键词： northern South china Sea, upper water structure, Late Pliocene, planktonic foraminifer, ODP 1146.