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Hydrogen and oxygen compositions of altered rocks from Qixia gold deposit and their genetic significance, Shandong, china

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Chinese Science Bulletin 1999年第S2期44卷 8-9页

作者： ZHAI Jianping, LU Jianjun, HU Kai and XU Guangping Department of Earth Sciences, state key, laboratory of mineral deposits, nanjing university, 210093, china Department of Earth Sciences State Key Laboratory of Mineral Deposits Nanjing University 210093 China

1 Sample and analytic methods The Qixia gold deposit is one of the important quartz vein-type deposits hosted in metamorphic rockin east Shandong Province, china. About 12 samples were collected at different depths of the Qixia goldmineral district to investigate the variations in the hydrogen and oxygen isotope compositions of alteredrocks. Hydrogen was extracted by melting samples and oxygen was obtained through oxidation by BrF5.The isotope compositions were measured with MAT252, and the precisions for oxygen and hydrogen isotope analyses were±0.2‰ and 2‰, respectively. All the analyses were fulfilled at the state key *** mineral deposit research in nanjing university. The δD and δ18O values relative to SMOW are givenin table 1.

关键词： hydrogen and oxygen isotopes altered rocks Qixia gold deposit Shandong.

Predicting octanol/water partition coefficient using solvation free energy and solvent-accessible surface area

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Journal of Environmental Sciences 2001年第3期13卷 299-303页

作者： LIU Xin hui, WU Chun de, HAN Shuo kui, WANG Lian sheng(state key laboratory of Pollution Control and Resource Reuse, Department of Environmental Science, School of the Environment, nanjing university, nanjing 210093, china. state key laboratory of Pollution Control and Resource Reuse Department of Environmental Science School of the Environment Nanjing University Nanjing 210093 China.

The regression model for octanol/water partition coefficients ( K ow ), is founded with only two molecular descriptors available through quantum chemical calculations: solvation free energy (Δ G S ), and solvent accessible surface area (SASA). For the properties of 47 organic compounds from 17 types, the model gives a correction coefficient (adjusted for degrees of freedom) of 0 959 and a standard error of 0 277 log unit. It is a suitable way to predict the partition properties that are related to solute solvent interactions in the water phase.

关键词： solvation free energy solvent accessible surface area quantum chemical descriptor

The optimization of replica distribution in the unstructured overlays

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Science china(Information Sciences) 2012年第3期55卷 714-722页

作者： FENG GuoFu1,2 , LI WenZhong2, LU SangLu2, CHEN DaoXu2 & BUYYA Rajkumar3 1School of Information Science, nanjing Audit university, nanjing 210029, china 2state key laboratory of Novel Software Technology, nanjing university, nanjing 210093, china 3Department of Computer Science and Software Engineering, The university of Melbourne, Victoria 3010, Australia 1. School of Information Science Nanjing Audit University Nanjing 210029 China2. State Key Laboratory of Novel Software Technology Nanjing University Nanjing 210093 China3. Department of Computer Science and Software Engineering The University of Melbourne Victoria 3010 Australia

Replication is a widely used technique in unstructured overlays to improve content availability or system performance. A fundamental question often addressed by previous work focused on: how many replicas ought to be allocated for each data item given the fixed query rates and limited storage capability? In this paper, we have put forth two optimal replica distributions to achieve the highest success rate and the lowest message consumption. Especially, we have investigated the influence of item size on replica distribution. Our results show that Square-Root Replication, which is traditionally considered to be optimal, is not always the best choice. Our study offers a new deep understanding of resource managment in self-organized unstructured overlays.

关键词： unstructured overlay item size distribution query rate success rate expected search size

SOME RESULTS ON GENERALIZED DIFFERENCE SETS

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Journal of Systems Science & Complexity 2008年第1期21卷 76-84页

作者： Xiwang CAO School of Mathematical Science, nanjing university of Aeronautics and Astronautics, nanjing 210016, china state key Lab. of Information Security, Beijing 100049, china. School of Mathematical Science Nanjing University of Aeronautics Astronautics Nanjing 210016 China state key Lab. of Information Security Beijing 100049 China

Sequences with ideal correlation functions have important applications in communications such as CDMA, FDMA, etc. It has been shown that difference sets can be used to construct such sequences. The author extends Pott and Bradley＇s method to a much broader case by proposing the concept of generalized difference sets. Some necessary conditions for the existence of generalized difference sets are established by means of some Diophantine equations. The author also provides an algorithm to determine the existence of generalized difference sets in the cyclic group Zv. Some examples are presented to illustrate that our method works.

关键词： Correlation functions diophantine equations generalized difference sets.

Wavelet estimation of the diffusion coefficient in time dependent diffusion models

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Science china Mathematics 2007年第11期50卷 1597-1610页

作者： Ping CHEN~(1,2+) Jin-de WANG~1 1 Department of Mathematics,nanjing university,nanjing 210093,china 2 School of Science,nanjing university of Science and Technology,nanjing 210094,china Department of Mathematics Nanjing University Nanjing 210093 China School of Science Nanjing University of Science Technology Nanjing 210094 China

The estimation problem for diffusion coefficients in diffusion processes has been studied in many papers,where the diffusion coefficient function is assumed to be a 1-dimensional bounded Lipschitzian function of the state or the time *** is no previous work for the nonparametric estimation of time-dependent diffusion models where the diffusion coefficient depends on both the state and the *** paper introduces and studies a wavelet estimation of the time-dependent diffusion coefficient under a more general assumption that the diffusion coefficient is a linear growth Lipschitz *** the properties of martingale,we translate the problems in diffusion into the nonparametric regression setting and give the Lr convergence rate.A strong consistency of the estimate is *** this result one can estimate the time-dependent diffusion coefficient using the same structure of the wavelet estimators under any equivalent probability *** example,in finance,the wavelet estimator is strongly consistent under the market probability measure as well as the risk neutral probability measure.

关键词： wavelet estimation time-dependent diffusion coefficient linear growth condition strong consistency

Mesoporous Si-MCM-48 membrane prepared by pore-filling method

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Science china(Technological Sciences) 2010年第4期53卷 1064-1068页

作者： XU DeKan & FAN YiQun state key laboratory of Materials-Oriented Chemical Engineering,College of Chemistry and Chemical Engineering,nanjing university of Technology,nanjing 210009,china 1. state key laboratory of Materials-Oriented Chemical Engineering College of Chemistry and Chemical Engineering Nanjing University of Technology Nanjing 210009 China

Mesoporous MCM-48 membranes were prepared on asymmetric zirconia tubular support with an average pore size of 0.2 μm by hydrothermal *** support should be pretreated with H2O as a pore-filling substance to prevent the sol solution from infiltrating into the support *** SEM showed that the MCM-48 membrane was composed of tightly-connected spherical *** single gas N2 and H2 permeation experiments confirm that crack-free membrane could be prepared by pore-filling method.N2 permeance of MCM-48 membrane,synthesized by secondary growth,can reach 5.66×10-7 mol/Pa·s·m2,and the H2/N2 separation factor was 3.47 under trans-membrane pressure of 0.05 MPa.

关键词： MCM-48 mesoporous membrane pore-filling

Progress and development in thermodynamic theory of friction and wear

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Science china(Technological Sciences) 2009年第4期52卷 844-849页

作者： DAI ZhenDong1 & XUE QunJi2 1 Institute of Bio-inspired Structure and Surface Engineering, nanjing university of Aeronautics and Astronautics, nanjing 210016, china 2 state key laboratory of Solid Lubrication, Chinese Academy of Sciences, Lanzhou 710000, china 1. Institute of Bio-inspired Structure and Surface Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China 2. state key laboratory of Solid Lubrication Chinese Academy of Sciences Lanzhou 710000 China

Tribology theory lags well behind engineering needs because of those complex and multi-dimensional characteristics associated with friction and wear. The mechanism of friction is reviewed and discussed from a static thermodynamics perspective; research methods on the process of friction and wear and thermodynamic studies within the field of tribology are also reviewed. We propose that entropy can be a critical parameter in describing the evolution of friction and wear, and the entropy balance equation could be considered as a fundamental cornerstone for a systematic tribology theory. Applications of irreversible thermodynamic theory of tribology to various fields are reviewed.

关键词： friction and wear irreversible thermodynamics entropy generation multi-factor coupling

A new measure to characterize multifractality of sleep electroencephalogram

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Science Bulletin 2006年第24期51卷 3059-3064页

作者： MA Qianli1,2,NING Xinbao1,WANG Jun2 & BIAN Chunhua1 1. state key laboratory of Modern Acoustics,Department of Electronics Science and Engineering,Institute for Biomedical Electronic Engi-neering,nanjing university,nanjing 210093,china 2. Province key laboratory of Image Processing & Image Communica-tion,College of Telecommunications and Information Engineering,nanjing university of Posts & Telecommunications,nanjing 210003,china state key laboratory of Modern Acoustics Department of Electronics Science and Engineering Institute for Biomedical Electronic Engineering Nanjing University Nanjing 210093 China Province key laboratory of Image Processing & Image Communication College of Telecommunications and Information Engineering Nanjing University of Posts & Telecommunications Nanjing 210003 China

Traditional methods for nonlinear dy-namic analysis,such as correlation dimension,Lyapunov exponent,approximate entropy,detrended fluctuation analysis,using a single parameter,cannot fully describe the extremely sophisticated behavior of electroencephalogram (EEG). The multifractal for-malism reveals more “hidden” information of EEG by using singularity spectrum to characterize its nonlin-ear dynamics. In this paper,the zero-crossing time intervals of sleep EEG were studied using multifractal analysis. A new multifractal measure Δasα was pro-posed to describe the asymmetry of singularity spec-trum,and compared with the singularity strength range Δα that was normally used as a degree indi-cator of multifractality. One-way analysis of variance and multiple comparison tests showed that the new measure we proposed gave better discrimination of sleep stages,especially in the discrimination be-tween sleep and awake,and between sleep stages 3 and 4.

关键词： sleep electroencephalogram multifractality.

EFFECTS OF SUBMERGED MACROPHYTES ON SEDIMENT SUSPENSION AND NH_4-N RELEASE UNDER HYDRODYNAMIC CONDITIONS

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Journal of Hydrodynamics 2010年第6期22卷 810-815页

作者： WANG Chao WANG Cun WANG Ze key laboratory of Integrated Regulation and Resource Department on Shallow Lakes Ministry of EducationHohai University Nanjing 210098 China state key laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing210098 China College of Mechanics and Materials Hohai University Nanjing 210098 China

Aquatic vegetation affects sediment suspension and nutrient release by changing the flow structure. Experiments on the influence of submerged vegetation on flow structure, sediment suspension, and NH4-N release were carried in a flume with natural submerged vegetation. Turbulence characteristics in the vegetation section were measured using a three-dimensional acoustic Doppler velocimeter. The effects of submerged vegetation on bed shear stress （ τb ）, sediment suspension, and NH4-N release were analyzed. Results show that with vegetation, bed shear stress is reduced by about 20% - 80%, which, in turn, reduces sediment suspension. The impact of submerged vegetation on sediment suspension and NH4-N release should be considered along with flow intensity. When the flow Reynolds number is relatively small, the submerged vegetation is quite capable of inhibiting sediment suspension and reducing NH4-N release, but when the Reynolds number reaches a certain value, the presence of aquatic plants exacerbates sediment suspension and promotes NH4-N release. Results also reveal that a highly significant positive correlation exists between NH4-N concentration and water turbidity in both vegetated and non-vegetated channels.

关键词： sediment suspension submerged macrophytes turbulence behavior bed shear stress turbidity