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Sensitive biosensing strategy based on functional nanomaterials

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science China Chemistry 2011年第8期54卷 1202-1217页

作者： JU HuangXian state Key Laboratory of Analytical Chemistry for Life science department of Chemistry, Nanjing university, Nanjing 210093, China 1. state Key Laboratory of Analytical Chemistry for Life science department of Chemistry Nanjing University Nanjing 210093 China

The first decade of the 21st century has been labeled as "the sensing decade". The functional nanomaterials offer excellent platforms for fabrication of sensitive biosensing devices, including optical and electronic biosensors. A lot of works have fo- cused on the biofunctionalization of different nanomaterials, such as metal nanoparticles, semiconductor nanoparticles and carbon nanostructures, by physical adsorption, electrostatic binding, specific recognition or covalent coupling. These biofunc- tionalized nanomaterials can be used as catalysts, electronic conductors, optical emitters, carriers or tracers to obtain the ampli- fied detection signal and the stabilized recognition probes or biosensing interface. The designed signal amplification strategies have greatly promoted the development of stable, specific, selective and sensitive biosensors in different fields. This review in- troduces some novel principles and detection strategies in the area of biosensing, based on functional nanomaterials. The gen- eral methods for biofunctionalization of nanomaterials with biomolecules and their biosensing application in immunoassay of protein, DNA detection, carbohydrate analysis and cytosensing are also described.

关键词： nanobiosensing biosensors nanomaterials biofunctionalization signal amplification bioanalysis biological recognition

Mechanism for calcite dissolution and its contribution to development of reservoir porosity and permeability in the Kela 2 gas field,Tarim Basin,China

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science China Earth sciences 2008年第4期51卷 567-578页

作者： YU BingSong1,3, DONG HailLiang2,3 & RUAN Zhuang1,3 1 state Key Laboratory of geological Processes and Mineral Resources, China university of Geosciences, Beijing 100083, China 2 {4. of Geology, Miami university,Oxford, oh 4.056, usa 3 Geomicrobiology Laboratory, China university of Geosciences, Beijing, 100083, China state Key Laboratory of geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China department of Geology Miami University Oxford OH 45056 USA Geomicrobiology Laboratory China University of Geoscien

This study is undertaken to understand how calcite precipitation and dissolution contributes to depth-related changes in porosity and permeability of gas-bearing sandstone reservoirs in the Kela 2 gas field of the Tarim Basin, Northwestern China. Sandstone samples and pore water samples are col-lected from well KL201 in the Tarim Basin. Vertical profiles of porosity, permeability, pore water chem-istry, and the relative volume abundance of calcite/dolomite are constructed from 3600 to 4.00 m below the ground surface within major oil and gas reservoir rocks. Porosity and permeability values are in-versely correlated with the calcite abundance, indicating that calcite dissolution and precipitation may be controlling porosity and permeability of the reservoir rocks. Pore water chemistry exhibits a sys-tematic variation from the Na2SO4.type at the shallow depth (3600-3630 m), to the NaHCO3 type at the intermediate depth (3630―3695 m),and to the CaCl2 type at the greater depth (3728―3938 m). The geochemical factors that control the calcite solubility include pH, temperature, pressure, Ca2+ concen-tration, the total inorganic carbon concentration (ΣCO2), and the type of pore water. Thermodynamic phase equilibrium and mass conservation laws are applied to calculate the calcite saturation state as a function of a few key parameters. The model calculation illustrates that the calcite solubility is strongly dependent on the chemical composition of pore water, mainly the concentration difference between the total dissolved inorganic carbon and dissolved calcium concentration (i.e., [ΣCO2] -[Ca2+]). In the Na2SO4.water at the shallow depth, this index is close to 0, pore water is near the calcite solubility. Calcite does not dissolve or precipitate in significant quantities. In the NaHCO3 water at the intermedi-ate depth, this index is greater than 0, and pore water is supersaturated with respect to calcite. Massive calcite precipitation was observed at this depth interval and

关键词： calcite dissolution porosity thermodynamic Tarim Basin

A Feedback-Based Web Search Engine

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Wuhan university Journal of Natural sciences 2004年第5期9卷 561-568页

作者： ZHANG Wei-feng 1,2,3 , XU Bao-wen 2,3,4., ZHOU Xiao-yu 2,3,4.1. department of Computer science and Engineering, Nanjing university of Posts and Telecommunications, Nanjing 210003, Jiangsu, China 2. department of Computer science and Engineering, Southeast university, Nanjing 210096, Jiangsu, China 3. Jiangsu Institute of Software Quality, Nanjing 210096 Jiangsu, China 4. The state Key Laboratory of Software Engineering, Wuhan university, Wuhan 4.0072, Hubei, China department of Computer science and Engineering Nanjing University of Posts and Telecommunications . Nanjing 210003 Jiangsu China

Web search engines are very useful information service tools in the Internet. The current web search engines produce search results relating to the search terms and the actual information collected by them. Since the selections of the search results cannot affect the future ones, they may not cover most people’s interests. In this paper, feedback information produced by the user’s accessing lists will be represented by the rough set and can reconstruct the query string and influence the search results. And thus the search engines can provide self-adaptability. Key words WWW - search engine - query reconstruction - feedback CLC number TP 311. 135.4.Foundation item: Supported by the National Natural science Fundation of China (60373066). National Grand Fundamental Research 973 Program of China (2002CB31200). Opening Foundation of state Key Laboratory of Software Engineering in Wuhan university, Opening Foundation of Jiangsu Key Laboratory of Computer Information Processing Technology in Soochow universityBiography: ZHANG Wei-feng (1975-), male, Ph.D. research direction: artificial intelligence, search engine, data mining, network language.

关键词： WWW search engine query reconstruction feedback

Sorption behavior of U(VI), ^(234.U(VI) and ^(238)U(VI) onto fracture-filling clays in Beishan granite, Gansu: Application to selecting the site of high-level radwaste repository in China

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science China Earth sciences 2005年第10期48卷 1649-1655页

作者： MIN Maozhong1,2, LUO Xingzhang3, WANG Ju4. JIN Yuanxin4.& WANG Rucheng1 1. department of Earth sciences, state Key Laboratory of Mineral Deposit Research, Nanjing university, Nanjing 210093, China 2. Center of Materials Analysis, Nanjing university, Nanjing 210093, China 3. department of Environmental science and Engineering, Nanjing university, Nanjing 210093, China 4. Beijing Geology Institute, Nuclear Industry, Beijing 100029, China department of Earth sciences State Key Laboratory of Mineral Deposit Research Nanjing University Nanjing China Center of Materials Analysis Nanjing university Nanjing China department of Environmental science and Engineering Nanjing university Nanjing China Beijing Geology Institute Nuclear Industry Beijing China

The first results of sorption experiments of U(VI), 234.(VI) and 238U(VI) onto original (unpurified) fracture-filling clays from No.1 monzonitic granite intrusion, Beishan area, Gansu Province, China are reported. The monzonitic granite intrusion is a potential location for a high-level radwaste (HLW) repository in China. The present experimental results show that the maximum U(VI) sorption reached 92% at near-neutral pH and the distribution coefficient (Kd) was 1226 mL/g. A high sorption capacity of the fracture-filling clays in host rock on radioactive ele-ments is necessary for HLW deep geological disposal repository. No preferential sorption of 234. onto the clays was found. Finally, the sorption of U(VI) onto the clays was also modeled using a surface complexation model.

关键词： HLW geological disposal repository, granite, uranium, radionuclide, clay, sorption.

Linear low-rank approximation and nonlinear dimensionality reduction

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science China Mathematics 2004年第6期47卷 908-920页

作者： ZHANG Zhenyue & ZHA Hongyuan department of Mathematics, Zhejiang university, Yuquan Campus, Hangzhou 310027, China department of Computer science and Engineering, The Pennsylvania {4. university, university Park, PA 16802, U.S.A. 1. department of Mathematics Zhejiang University Yuquan Campus 310027 Hangzhou China 2. department of Computer science and Engineering The Pennsylvania State University 16802 University Park PA USA

We present our recent work on both linear and nonlinear data reduction methods and algorithms: for the linear case we discuss results on structure analysis of SVD of columnpartitioned matrices and sparse low-rank approximation; for the nonlinear case we investigate methods for nonlinear dimensionality reduction and manifold learning. The problems we address have attracted great deal of interest in data mining and machine learning.

关键词： singular value decomposition low-rank approximation sparse matrix nonlinear dimensionality reduction principal manifold subspace alignment data mining

DISCRETE APPROXIMATIONS FOR SINGULARLY PERTURBED BOUNDARY VALUE PROBLEMS WITH PARABOLIC LAYERS, III

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Journal of Computational Mathematics 1996年第2期14卷 273-290页

作者： P.A. Farrell(department of Mathematics and Computer science, Kent state university,{4.)P.W. Hemker(CWI Center for Mathematics and Computer science, Amsterdam, The Netherlands)G.I. Shishkin(IMM, Institute of Mathematics and Mechanics, Ural Branch of the Kent state university 美国 Center for Mathematics and Computer science 荷兰 Institute of Mathematics and Mechanics 俄罗斯

In this series of three papers we study singularly perturbed (SP) boundary vaue problems for equations of elliptic and parabolic troe. For small values of the perturbation parameter parabolic boundary and interior layers appear in these problems. If classical discretisation methods are used, the solution of the finite difference scheme and the approximation of the diffusive flux do not converge uniformly with respect to this parameter. Using the method of special, adapted grids,we can construct difference schemes that allow approkimation of the solution and the normalised diffusive flux uniformly with respect to the small *** also consider singularly perturbed boundary value problems for convection diffusion equations. Also for these problems we construct special finite difference schemes, the solution of which converges E-uniformly We study what problems appear, when classical schemes are used for the approximation of the spatial deriva tives. We compare the results with those obtained by the adapted approach. Results of numerical experiments are *** the three papers we first give an introduction on the general problem, and then we consider respectively (i) Problems for SP parabolic equations, for which the solution and the normalised diffusive fluxes are required; (ii) Problems for SP elliptic equations with boundary conditions of Dirichlet, Neumann and Robin type;(iii) Problems for SP parabolic eqllation with discontinuous boundaxy conditions

关键词： III DISCRETE APPROXIMATIONS FOR SINGULARLY PERTURBED BOUNDARY VALUE PROBLEMS WITH PARABOLIC LAYERS

An optimization approach to cycle quality network chain based on improved SCOR model

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Progress in Natural science:Materials International 2009年第7期19卷 881-890页

作者： Renbin Xiao a, Zhengying Caib, Xinhui Zhangc a Institute of Systems Engineering, Huazhong university of science and Technology, Wuhan 4.0074. China b School of Management, Huazhong university of science and Technology, Wuhan 4.0074. China c {4. of Biomedical, Industrial & Human Factors Engineering, Wright state university, Dayton, oh 4.4.5, usa [a]Institute of Systems Engineering Huazhong University of Science and Technology Wuhan 430074 China [b]School of Management Huazhong University of Science and Technology Wuhan 430074 China [c]Department of Biomedical Industrial & Human Factors Engineering Wright State University Dayton OH 45435 USA

Based on the improved supply chain operations reference (SCOR) model, a network-topology structure of cycle quality chain operations reference (CQCOR) model is built up, which realizes the cycle operation by an added quality process of reverse manufacturing. The concept of cycle quality chain management is defined, and its cost structure is analyzed according to positive and reverse quality processes. If the quality level is controlled by the positive quality cost, then the reverse quality cost is a nonlinear function of quality level. All the quality processes are connected by acceptable probability, so the optimized objective function is described as a fuzzy multi-objective function comprising maximum of the total profit of quality chain, maximum of the recycling efficiency and maximum of environment protection and source saving. The effects of different quality policies on fuzzy rules are compared by a simplified example. When the policy of recycling efficiency dominates, the total quality profit will be less than that of maximum profit policy.

关键词： Quality chain Cycle operation Quality cost SCOR

MEAM Potential with Angular Dependence for TiAl

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Rare Metals 2001年第1期20卷 13-17页

作者： Xiaodong Ni, Xitao Wang, Guoliang Chen (Physics department, university of science and Technology Beijing, Beijing 100083, China state Key Laboratory for Advanced Metals and Materials, university of science and Technology Beijing, Beijing 100083, China) Univ Sci & Technol Beijing Dept Phys Beijing 100083 Peoples R China Univ Sci & Technol Beijing State Key Lab Adv Met & Mat Beijing 100083 Peoples R China

The modified embedded atom method (MEAM) is an empirical extension of the embedded atom method (EAM) that includes angular forces. By fitted to the lattice constants, the cohesive energy, the APE (anti-phase boundary) energy, and the vacancy formation energy of TiAl, an accurate MEAM potential is obtained for the TiAl system with L10 structure. The calculation results of the properties of TiAl are in good agreement with experiments and the results of first principle (F.P.) calculations.

关键词： embedded atom method TiAl alloy angular dependence potential intermetallics

Estimating the spatial distribution of organic carbon density for the soils of ohio, usa

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Journal of Geographical sciences 2013年第2期23卷 280-296页

作者： Sandeep KUMAR Rattan LAL Desheng LIU Rashid RAFIQ departmentofPlantscience.Room24.CNPB BOX2140C1110RotundaLaneNorthSouthDakotaStateUniversityBrookingsSD57007USA CarbonManagementandSequestrationCenter SchoolofEnvironmentandNaturalResourcesTheOhioStateUniversity2021CoffeyRoad414AKo~manHallColumbusOH43210-1085USA departmentofGeographyanddepartmentofStatistics TheOhioStateUniversityColumbusOH43210USA departmentofMicrobiology&PlantBiology.universityofOklahoma NormanOK73019USA

Historical database of National Soil Survey Center containing 14.4.geo-referenced soil profiles was used in this study for estimating the organic carbon （SOC） for the soils of ohio, usa. Specific objective of the study was to estimate the spatial distribution of SOC density （C stock per unit area） to 1.0-m depth for soils of ohio using geographically weighted regression （GWR）, and compare the results with that obtained from multiple linear regression （MLR）. About 80% of the analytical data were used for calibration and 20% for validation. A total of 20 variables including terrain attributes, climate data, bedrock geology, and land use data were used for mapping the SOC density. Results showed that the GWR provided better estimations with the lowest （3.81 kg m-2） root mean square error （RMSE） than MLR approach Total estimated SOC pool for soils in ohio ranged from 727 to 74. Tg. This study demon strates that, the local spatial statistical technique, the GWR can perform better in capturing the spatial distribution of SOC across the study region as compared to other global spatial statistical techniques such as MLR. Thus, GWR enhances the accuracy for mapping SOC density.

关键词： geographically weighted regression multiple linear regression major land resource areas root meansquare error soil organic carbon