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Progress in study on endocrine disrupting pesticides (EDPs) in aquatic environment

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Science Bulletin 2005年第20期 3-12页

作者： XUE Nandong1. 2. WANG Hongbo2.& XU Xiaobai1. 1. State Key Laboratory of Environmental chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 1.0085, China 2. {1. of Environmental Sciences and Engineering, hunan Ag- ricultural University, {3. 41.1.8, China

Background on the generation of the problems of endocrine disrupting pesticides (EDPs) in aquatic environment, characteristics of EDPs, adverse effects and their effect mechanism of EDPs on human and wildlife, the transportation and degradation pathways of EDPs in water and analysis methods of EDPs in water were reviewed. The importance of EDPs in water should be attached to adverse effects on wildlife and human health. It was advised to estab- lish research programs on EDPs in aquatic environment es- pecially in water supply source.

关键词： endocrine disrupting pesticides (EDPs) aquatic envi- ronment.

Chronological and geochemical studies of granite and enclave in Baimashan pluton, hunan, South China

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Science China Earth Sciences 2007年第11期50卷 1606-1627页

作者： CHEN WeiFeng1. CHEN PeiRong1. HUANG HongYe2. DING Xing1.3.& SUN Tao1.1.State Key Laboratory of Mineral Deposit Research, {1. of Earth Sciences, Nanjing University, Nanjing 2.0}093. China 2.Research Institute No.2.3}, CNNC, changsha 41.01., China 3.Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 51.640, China 1. State Key Laboratory of Mineral Deposit Research Department of Earth Sciences Nanjing University Nanjing 210093 China 2. Research Institute No.2.0} CNNC Changsha 410011 China 3. Guangzhou Institute of Geo{1. Chinese Academy of Sciences Guangzhou 510640 China

Zircon LA-ICP-MS U-Pb dating reveals that the Baimashan Pluton is composed mainly of late Indosinian (2.4.5±2.8 Ma-2.9.2.3.8 Ma) biotite granodiorites/monzonitic granites (LIGs) and early Yanshanian (1.6.7±1.7 Ma) two-micas monzonitic granites (EYGs), and the coeval (2.3.2.4.5 Ma-2.5.1.3.9 Ma) mafic microgranular enclaves (MMEs) are generally found in the former. In addition, the ages of cores within zircons from LIGs and MMEs ranging from 2.1.4±4.0 Ma to 2.6.5±4.1.a provide evidence of multistage magma intrusion during Indosinian in the study area. Measured 3.1.±2..6 Ma of inherited zircon age suggests that there may be recycling Archaean curstal material in existence in this area. LIGs and EYGs share some similar geochemical features: subalkaline and peraluminous granites, enrichment of Th, U, K, Ta, Zr, Hf and LREE but depletion of Ba, Nb, P, Ti and Eu, low εNd(t) values but high (87Sr/86Sr)i ratios, and old T2.M (ca. 1.9-2.0 Ga). The behaviors of incompatible elements and REE are mainly dominated by fractional crystallization of plagioclase, K-feldspar, ilmenite and apatite, but that of Sr isotope mainly controlled by EC-AFC. They are crust-sourced and derived from partial melting of paleo-Proterozoic metagreywackes and related to biotite dehydration melting. LIGs are formed in post-collisional tectonic setting as crustal local extension and thinning during late Indosinian. But EYGs may be evolved products of congeneric granitic magma with LIGs formed in late Indoinian, which were emplaced again when crust underwent extensive thinning and extension in post-orogenic tectonic setting during Yanshanian in SC after undergoing EC-AFC. MMEs should be cognate enclaves and derived from liquid immiscibility of host magma.

关键词： granite,mafic microgranular enclave,zircon LA-ICP-MS dating,lithogenesis,EC-AFC

Moving collocation methods for time fractional differential equations and simulation of blowup

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Science China Mathematics 2011年第3期54卷 611-622页

作者： MA JingTang1.& JIANG YingJun2.1.chool of Economic Mathematics, Southwestern University of Finance and Economics, Chengdu 61.1.0}, China 2.1. of Mathematics and Scientific Computing, changsha University of Science and Technology, changsha 41.076, China 1. School of Economic Mathematics Southwestern University of Finance and Economics Chengdu 611130 China2. Department of Mathematics and Scientific Computing Changsha University of Science and Technology Changsha 410076 China

A moving collocation method is proposed and implemented to solve time fractional differential equations. The method is derived by writing the fractional differential equation into a form of time difference equation. The method is stable and has a third-order convergence in space and first-order convergence in time for either linear or nonlinear equations. In addition, the method is used to simulate the blowup in the nonlinear equations.

关键词： moving collocation methods time fractional differential equations blowup

DECOMPOSITION OF BV FUNCTIONS IN CARNOT-CARATHEODORY SPACES

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Acta Mathematica Scientia 2003年第4期23卷 433-439页

作者：宋迎清杨孝平刘振海 School of Science Nanjing University of Science and Technology Nanjing 210094 China Department of Mathematics Hunan University of City Yiyang 413000 China School of Science Nanjing University of Science and Technology Nanjing 210094 China department of Mathematics Changsha University of Electrical Power Changsha 410077 China

The aim of this paper is to get the decomposition of distributional derivatives of functions with bounded variation in the framework of Carnot-Caratheodory spaces (C-C spaces in brievity) in which the vector fields are of Carnot type. For this purpose the approximate continuity of BV functions is discussed first, then approximate differentials of L1.functions are defined in the case that vector fields are of Carnot type and finally the decomposition Xu = (?)u ·Ln + X2.u is proved, where u ∈ BVx(?) and (Ω)u denotes the approximate differential of u.

关键词： BV function C-C space Radon measure vector field approximate differential

CRITERION OF POSITIVE DEFINITENESS OF MATRICES AND SOLUTION OF INVERSE PROBLEM FOR SYSTEM OF LINEAR EQUATIONS

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Chinese Science Bulletin 1989年第2期34卷 89-94页

作者：郭忠 department of Mathematics Hunan University Changsha

The class of symmetric definitely positive matrices is extremely important in the matrix theory. At present, positive definiteness of a symmetric matrix can be shown by determining the signs of its all ordered princip... 详细信息

关键词： cneralized positively definite matrix inverse problem general solution.

Determination of thermal conductivity of magnesium-alloys

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Journal of Central South University of Technology 2001年第1期8卷 60-63页

作者： ZHOU Jie min 1.YANG Ying 1.Magne Lamvik 2.WANG Gang 1.(1.department of Applied Physics and Heat Engineering, Central South University, {1. 41.083. China 2.Norwegian University of Science and Technology) 1. department of Applied Physics and Heat Engineering Central South University 410083 Changsha China 2. Norwegian University of Science and Technology China

An indirect method, Angstroms method was adopted and an instrument was designed to determine the thermal conductivity of magnesium metal and alloys. Angstroms method is an axial periodic heat flow technique by which the thermal diffusivity can be measured directly. Then thermal conductivity can be obtained with relation to thermal diffusivity. Compared with the recommended data from the literature the fitted values of the thermal diffiusivity correspond with 3., and the credible probability of the thermal conductivity in the range of 0 450 ℃ is about 95%. The method is applicable in the given temperature range.

关键词： angstroms method thermal conductivity thermal diffusivity magnesium alloy

Dispersion of ultrafine alumina in modifier solution ——the role of polar interfacial interaction

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Journal of Central South University of Technology 2001年第1期8卷 18-23页

作者： HU Yue hua 1.QIU Guan zhou 1.J.D.Miller 2.(1.department of Mineral Engineering, Central South University, {1. 41.083. China 2.department of Metallurgical Engineering, University of Utah, 41. WBB, Salt Lake City, UT 841.2. USA) 1. department of Mineral Engineering Central South University 410083 Changsha China 2. department of Metallurgical Engineering University of Utah 412 WBB 84112 Salt Lake City UT USA

Dispersion of ultrafine alumina suspension is examined by using particle size analyzer. The zeta potential and contact angle measurements were used to discuss the electrokinetic behavior and surface wettability of alumina in modifier solution, and to calculate the electrostatic interaction forces and interfacial interaction forces between alumina particles. The aggregation of ultrafine alumina occurs near its PZC. Addition of modifier increases the zeta potential of alumina and its surface hydrophilicity, resulting in increase of electrostatic and hydration repulsion. It makes the suspension of ultrafine alumina completely dispersed. The average particle size of the suspension is decreased from 1.73.μm in absence of modifier to 0.8 μm in the presence of tripolyphosphate. According to polar interfacial interaction approach, the hydration forces responsible for the stability of alumina suspension in the presence of modifier have also been obtained. The extended DLVO theory is successful to describe the dispersion behavior of ultrafine alumina in modifier solution.

关键词： dispersion alumina modifier polar interfacial interaction extended DLVO theory

Effect of Tocopherol on Antioxygenic Properties of Green Lubricating Oil

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Journal of Wuhan University of Technology(Materials Science) 2008年第3期23卷 289-292页

作者：肖志信 College of Mechanical and Electrical Engineering Central South University department of Mechanical Engineering Hunan Institute of TechnologyHengyang 421002China

Based on the needs of green motor oil, and in order to improve the antioxidation properties of green lubricating oil, the effect of tocopherol antioxidation properties of rapeseed oil was studied. Experiments of high temperature oxidation, antiwear and infra-red spectrum analysis were accomplished, the results show that the rapeseed oil including tocopherol can still keeps steady structure after high temperature oxidation, with a small variety of acid number, whose antioxygenic properties are improved evidently. Meanwhile, both thiocarbamate and vitamin C play an assistant role in tocopherol, which can make rapeseed oil to have better oxidation stability and keep excellent antiwear properties after high temperature oxidation.

关键词： rapeseed oil tocopherol antioxygenic properties

SYNTHESES AND UV SPECTRA OF SALICYLADEHYDE DERIVATIVES

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Journal of Central South University 1998年第2期10卷 65-67页

作者： Tang Ruiren (department of {1., Central South University of Technology,{2. 41.083.China) department of {1. Central South University of Technology Changsha 410083 China

Nine 5 (β substituted stylryl) salicyladehyde derivatives were prepared by PTC Witting reactions in the paper . The stereochemistry of the Witting reactions and the substituted effect on the UV spectra of salicyladehyde derivaties have been reported . It was observed that the spectra undergo a red shift as the conjugative effect of substituted becomes stronger . A good linear relationship between the shift of UV of p substituted compounds and conjugation effect was *** showed that the Hammett equation may be applied to the UV frequencies of the title compounds.

关键词： substituted strlrylsalicyladehyde derivatives substituted effect Witting reaction UV spectra