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Surface interrogation mode of scanning electrochemical microscopy for oxidation study of adsorbed CO generated from serine on platinum

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Chinese Chemical Letters 2011年第12期22卷 1481-1484页

作者： Chun Cui Huang,Qian Wang,De Bo Xiang,Hui Bo Shao~* Key Laboratory of Cluster Science,Ministry of Education of china,school of Chemistry, beijing institute of technology,beijing 100081,china Key Laboratory of Cluster Science Ministry of Education of China School of Chemistry Beijing Institute of Technology Beijing 100081 China

We report a new method for detection and oxidation of adsorbed carbon monoxide(CO;) generated from serine on a polycrystalline platinum ultramicroelectrode（UME） by bromine（Br;） using in situ surface interrogation（SI） mode of scanning electrochemical microscopy（SECM）.In the SI mode,tip and substrate are both pt UMEs,and CO;on pt substrate,generated from serine,can be oxidized by the tip-generated Br;giving a positive *** CO;from serine instead of purging CO gas expands the newly introduced reaction of Br;with CO;and further enhances the hope to get rid of CO;on pt for fuel cells.

关键词： SECM Surface interrogation mode Adsorbed carbon monoxide Serine pt ultramicroelectrode

The Self-assembling and Application of Inorganic Anti-bacterial Material Made of Natural Nanoporous Carrier

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Journal of Wuhan University of technology(Materials Science) 2008年第6期23卷 771-774页

作者：孙春宝 school of Civil and Environmental Engineering University of Science and Technology Beijing

The inorganic antimicrobial material was inhibited to the microbes with the added metal ion,*** primary wet product carrying 5%-10% zinc ion was generated under the following conditions：temperature was 95 ℃,solution zinc concentration was 1.2-2.0 mol/L,and the ratio of Zn solution to zeolite weight was 5：*** final stable product was manufactured after baking in an oven for 1-3 h at the temperature of 500-900 ℃.The baked material was tested for its disinfection effectiveness and coloring effect when mixed with paint *** on the final batch of tests,the zinc content of this anti-microbial product was further optimized.

关键词： inorganic antimicrobial nanoporous material antibacterial coating zeolite self-assembling

Entropy number and non-linear approximations on multivariate Besov space by manifolds of finite pseudo-dimension

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progress in Natural Science:Materials International 2006年第3期16卷 260-265页

作者： LONG Jingfan and FANG Gensun (school of Mathematical Sciences, beijing Normal University, beijing 100875, china Department of Computer Science, Information technology institute, beijing 100101, china) [a]school of Mathematical Sciences Beijing Normal University Beijing China [b]Department of Computer Science Information Technology Institute Beijing China

We determine the asymptotic order of entropy number and optimal non -linear approximations of anisotropic periodic Besov class of Bpθr(Td') (1≤p≤∞,1≤0≤∞) by manifolds of finite pseudo-dimension in the metric Lq... 详细信息

关键词： pseudo-dimension anisotropic Besov class of functions entropy number nonlinear width.

On three-dimensional geological modeling and visualization

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Science china Earth Sciences 2004年第8期47卷 739-748页

作者： WU Qiang1 & XU Hua2 1. Department of resource Exploitation Engineering, china University of Mining and technology, beijing 100083, china 2. beijing institute of petrochemical technology, beijing 102617, china 1. Department of resource Exploitation Engineering China University of Mining and Technology 100083 Beijing China 2. beijing institute of petrochemical technology 102617 Beijing China

The technology of 3D geological modeling will bring about great changes in the methods of geological data acquiring, storing, processing and displaying. However, no perfect or convenient software systems have been developed up to now since the geologic data which re-flect geological entities bear the feature of diversity, uncertainty and complexity. Some supervoxel models, mathematical models of fault and geometrical models of fold have been contrived so as to show the space geometric configuration of the complicated geologic structures. The application-oriented system architecture for 3D geological modeling is established; and a novel design concept based on spatial data processing is also proposed with the technology of solid modeling as its core and the application of models as its objective. Theories and methods for 3D geological modeling will hopefully be enriched and developed. In the light of these theories and methods, a feature-based navigation visualization technique is also put forward in the paper. By integrating geo-database, graphics libraries and KBS with 3D dynamic simulation systems, geologists will be able to capture the partial characteristics and whole structure embodied in the geological data in a direct-viewing, figurative and accurate manner.

关键词： 3D geological modeling,geometrical model,system architecture,visualization

A Good GC Stationary phase for Separation of Xylene Isomers

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Chinese Chemical Letters 1999年第1期10卷 45-46页

作者： Ting ZHANG Jiang Hua HAN ruo Nong FU Jian ZHANG(school of Chemical Engineering & Materials, beijing institute of technology, beijing 100081) beijing Inst Technol Sch Chem Engn & Mat Beijing 100081 Peoples R China

An excellent separation of xylene isomers is reported using 2, 6-O-di-pentyl-3-O-acetyl-beta-CD as capillary stationary phase. The optimum conditions for the separation are also discussed.

关键词： xylene isomers separation capillary stationary phase optimum conditions for separation

OXIDATION rESISTANCE AND MECHANICAL prOpErTIES OF Ti_3Al-Nb-Mo-Si ALLOYS

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Acta Metallurgica Sinica(English Letters) 1995年第Z1期8卷 577-582页

作者： SUN Yufeng CAO Chunxiao CAO Jingxia YAN Minggao (beijing institute of Aeronautical Materials,beijing,100095),p.r.china beijing Inst of Aeronautical Materials Beijing China

In the present paper,the development of Ti3Al-Nb-Mo-Si alloys for high oxidation resistance is *** of weight gain of alloys with different Nb and Si addition is tested,the evaluation of comprehensive mechanical properties has been taken,include the room-temperature and 700℃ tensile properties,thermal stability,creep rupture and fracture toughness of the alloys,It has shown that the oxidation resistance and mechanical properties were significantly affected by the variation of Nb and Si *** composition with the best balance of properties is Ti-24Al-13Nb-1.5Mo-0.5Si and Ti-24Al-15Nb-1.5Mo,which is mush higher than that of Super,α_2 alloy (Ti-25Al-10Nb-3V-1Mo).

关键词： Ti_3Al alloy oxidation resistance mechanical properties

recent advances in the data analysis method of functional magnetic resonance imaging and its applications in neuroimaging

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progress in Natural Science:Materials International 2006年第8期16卷 785-795页

作者： TIAN Jie, YANG Lei and HU Jin (institute of automation, Chinese Academy of Sciences, beijing 100080, china Graduate school of Chinese Academy of Sciences, beijing 100039, china) [a]Chinese Academy of Sciences Institute of Automation Beijing China [b]Graduate school of Chinese Academy of Sciences Beijing China

Functional magnetic resonance imaging (fMrI) has opened a new area to explore the human brain. The fMrI can reveal the deep insights of spatial and temporal changes underlying a broad range of brain function, such as motor, vision, memory and emotion, all of which are helpful in the clinical investigation. In this paper, we introduce some recent-developed algorithms for fMrI signal detection such as model-driven method (general linear model, deconvolution model, non-linear model, etc. ) and data-driven method (principle component analysis, independent component analysis, self-organization mapping, clustered constrained non-negative matrix factorization, etc. ). We also propose several important applications of neuroimaging and point out their shortcomings and future perspectives.

关键词： fMr1 data analysis neuroimaging.

Electrochemical studies of nickel deposition from aqueous solution in super-gravity field

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Science china(Technological Sciences) 2007年第1期50卷 39-50页

作者： GUO ZhanCheng1,2, GONG Yingpeng2 & LU WeiChang2 1 Metallurgical & Ecological school, University of Science and technology, beijing 100083, china 2 institute of process Engineering, Chinese Academy of Sciences, beijing 100080, china 1. Metallurgical & Ecological school University of Science and Technology Beijing 100083 China 2. institute of process Engineering Chinese Academy of Sciences Beijing 100080 China

The effect of super-gravity on electrochemical deposition of nickel from aqueous solution was studied. The SEM pictures show that the microstructure of nickel film deposited under the super-gravity condition is finer and more uniform compared with that obtained in normal gravity condition, and the crystal grains diminish with the increase of super-gravity coefficient. The XrD patterns indicate that the arrangement of crystalline grains of nickel film deposited under the super-gravity field is more regular, and the crystalline grain sizes decrease with the increase of super-gravity coefficient. Toughness, tensile stress and hardness of the nickel film are markedly raised with the increase of super-gravity coefficient, and hydrogen content in the nickel film decreases with the increase of super-gravity coefficient. From the polarization curves of hydrogen evolution reaction under the super-gravity condition, a significant reduction of over-potential on electrode was found when current density increased. The process of hydrogen evolution reaction was enhanced under the super-gravity condition. The electro-deposition rate, the microstructure and properties of deposited nickel film under super-gravity condition were still affected by the relative orientation between inertia force and depositing surface. It is favorable to gain the nickel film with better mechanic properties when inertia force orientates vertically towards depositing surface. Keywords super-gravity - electrochemistry - electro-deposition - nickel film Supported by the Notional Natural Science Foundation of china (Grant No. 50674011)

关键词： super-gravity electrochemistry electro-deposition nickel film

Fracture characteristics of concrete subjected to impact loading

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Science china(physics,Mechanics & Astronomy) 2010年第9期53卷 253-261页

作者： LIU HaiFeng1,2,LIU HaiYan3 & SONG WeiDong1 1 State Key Laboratory of Explosion Science and technology,beijing institute of technology,beijing 100081,china 2.school of Civil and Hydraulic Engineering,Ningxia University,Yinchuan 750021,china 3 school of Science,beijing institute of technology,beijing 100081,china 1. State Key Laboratory of Explosion Science and technology Beijing Institute of Technology Beijing 100081 China2. School of Civil and Hydraulic Engineering Ningxia University Yinchuan 750021 China3. School of Science Beijing Institute of Technology Beijing 100081 China

This paper takes concrete as a four-phase composite made of the intact matrix and three mutually perpendicular groups of penny-shaped micro-cracks. The intact matrix is assumed to be elastic,homogeneous and isotropic,and the micro-cracks are penny-shaped. Combined with the failure mechanism of concrete subjected to impact loading,a dynamic constitutive model for concrete is developed based on Mori-Tanaka's average stress concept and Eshelby's equivalent inclusion theory. Experimental results show that concrete is rate-dependent. The model predictions are in good agreement with the experimental results. The model may be used to simulate the mechanical behavior of concrete under impact loadings.

关键词： concrete micromechanics impact loading constitutive model

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