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Catalytic reduction of NO_x by biomass-derived activated carbon supported metals

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Chinese Journal of Chemical Engineering 2018年第10期26卷 2077-2083页

作者： yun shu Fan Zhang Fan Wang Hongmei Wang Research Center of Air Pollution Control Technology Chinese Research Academy of Environmental Sciences

In this study,to prepare a series of activated carbon-supported metals for the catalytic reduction of NO_x to N_2 in excess O_2,activated carbons derived from lignocellulosic and herbaceous biomasses were selected as the reducing agents,and alkali and transition metals were used as the catalytic active *** effects of the type of biomass,carbonization temperature and catalyst composition on NO_x reduction efficiency were analyzed in a fixed-bed flow *** results showed that two temperature regimes are present for the NO_x-carbon reaction:at temperatures below 250°C,the NO_x adsorption process on the carbon surface was predominant,whereas true NO_x reduction by carbon occurred at temperatures above 250°C,producing N_2,CO_2 and *** influence of the carbonization temperature on carbon reactivity depended on the effect of the carbonization temperature on the carbon surface area and the reduction of the metal species on *** studied metals catalyzed both NO_xand O_2reduction by carbon,and potassium could strongly enhance the C-NO_x reaction without substantial carbon consumption by O_***,the potassium supported by sawdust-derived activated carbon exhibited higher selectivity and capacity towards NO_x reduction than did its previously reported coal-derived *** properties were ascribed to the high dispersion of the active potassium species on the carbon surface,as observed through the comparison of X-ray photoelectron spectroscopy and powder X-ray diffraction results for the carbons made from biomass and coal-based precursors.

关键词： Biomass NOx reduction Activated carbon Selectivity

NUMERICAL SIMULATION OF UNSTEADY FLOW FOR VISCO- ELASTIC FLUID IN AN ECCENTRIC ANNULUS WITH INNER ROD RECIPROCATION

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Journal of Hydrodynamics 2008年第2期20卷 261-266页

作者： HE Feng-yun YANG shu-ren Department of Petroleum Engineering Daqing Petroleum Institute Daqing 163318 China

The equation governing the unsteady flow of viscoelastic fluids in an eccentric annulus was derived by using the common conversion Maxwell fluid constitutive equation and then discretized by the control volume method. The velocity distribution of flow field was computed by using the ADI method. The influences of the pressure gradient, eccentricity, stroke length, and stroke frequency on the velocity and flow capacity in the flow field was analyzed. The foundation for further research of the eccentric wear problem of the pumping rod in polymer-flood well was laid.

关键词： polymer-flood well viscoelastic fluid eccentric annulus unsteady flow eccentric wear

Mechanism of the Selective Catalytic Reduction of NOx with NH3 over W-Doped Fe/TiO2 Catalyst

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Chemical Research in Chinese Universities 2014年第6期30卷 1005-1010页

作者： shu yun WANG Hongchang ZHU Jinwei ZHANG Fan Research Center of Air Pollution Control Technology Chinese Research Academy of Environmental Sciences Beijing 100012 P. R. China

The W-doped Fe/TiO2 catalyst prepared by an impregnation method exhibited a good NH3-selective cata- lytic reduction（SCR） activity and N2 selectivity with broad operation temperature window. The interaction between Fe and W could increase the amount of surface chemisorbed oxygen, and thus enhances the low temperature SCR activity by facilitating the fast SCR of 2NH3＋NO＋NO2 →2N2＋3H2O. The NH3-SCR reaction mechanism over the W-Fe/TiO2 was fully investigated via in situ diffuse reflectance infrared Fourier transform spectroscopy（in situ DRIFTS）. In the low temperature range（〈250 ℃）, the reactive surface species were mainly coordinated NH3, ionic NH~ and adsorbed NO2 species, and the SCR mainly followed the Langmuir-Hinshelwood mechanism, during which the adsorbed NO2 species became the important active sites. In the high temperature range（〉250 ℃）, the reactive surface species were mainly NH2, and the SCR mainly followed the Eley-Rideal mechanism, during which the for- mation of NH2NO intermediate species after H-abstraction of NH3 was the rate-determining step.

关键词： Selective catalytic reduction Iron Tungsten Reaction mechanism

A Vertex Cover with Chorded 4-cycles

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Acta Mathematica Sinica,English Series 2011年第12期27卷 2351-2360页

作者： yun shu GAO Guo Jun LI Jin YAN School of Mathematics and Computer Science Ningxia University Yinchuan 750021 P. R. China Department of Biochemistry and Molecular Biology University of Georgia GA 30602 U.S.A. School of Mathematics Shandong University Ji＇nan 250100 P. R. China

Let k be an integer with k ≥ 2 and G a graph with order n 〉 4k. We prove that if the minimum degree sum of any two nonadjacent vertices is at least n ＋ k, then G contains a vertex cover with exactly k components su... 详细信息

关键词： Degree condition vertex-disjoint chorded quadrilateral

Simultaneous nitrification and denitrification in step feeding biological nitrogen removal process

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Journal of Environmental Sciences 2007年第9期19卷 1043-1048页

作者： ZHU Gui-bing PENG Yong-zhen WU shu-yun WANG shu-ying XU Shi-wei School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Belting 100085 China. Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering Beijing University of Technology Beijing 100022 China Beijing Drainage Group Co. Ltd. Beijing 100038 China

The simultaneous nitrification and denitrification in step-feeding biological nitrogen removal process were investigated under different influent substrate concentrations and aeration flow rates. Biological occurrence of simultaneous nitrification and denitrification was verified in the aspect of nitrogen mass balance and alkalinity. The experimental results also showed that there was a distinct linear relationship between simultaneous nitrification and denitrification and DO concentration under the conditions of low and high aeration flow rate. In each experimental run the floc sizes of activated sludge were also measured and the results showed that simultaneous nitrification and denitrification could occur with very small size of floc.

关键词： biological nitrogen removal dissolved oxygen floc size simultaneous nitrification and denitrification step feeding process

Synthesis of visible-light-driven TiO_(2) yolk-shell spheres with {001} facets dominated mesoporous shells

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Chinese Chemical Letters 2013年第3期24卷 260-263页

作者： Hui Wang Bi-Li Wang shu-yun Ma Institute of Science PLA University of Science&TechnologyNanjing 21101China

Anatase phase visible-light-driven TiO_(2) yolk-shell spheres with the size of ca.1-2 um have been synthesized with the combination of solvothermal and heat treatment ***,SEM,TEM,XPS,and PL analysis were used to examine structure and properties of the *** N species and Ti3+centers introduced into the as-prepared photocatalyst can enhance the visible light absorption *** mesoporous shell of the prepared photocatalyst,which promotes the pollutant adsorption ability,consists of the high-reactive[001]facets dominated *** to the unique structure,it is also observed that the as-prepared visible-light-driven TiO_(2) yolk-shell spheres exhibit a sunerinr nhnrncatalvtic activity for organic dyes decomposition than the well-known P25.

关键词： Titanium dioxide {001}Facet Photocatalysis Visible light

Mechanisms of resistance to spinosad in the western flower thrip, Frankliniella occidentalis （Pergande）（Thysanoptera： Thripidae）

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Insect Science 2008年第2期15卷 125-132页

作者： shu-yun Zhang Satoshi Kono Tamotsu Murai Tadashi Miyata Laboratory of Applied Entomology Graduate School of Bioagricultural Sciences Nagoya University Chikusa Department of EnvironmentalConservation Hyogo Prefectural Institute of Agnculture Forestry and Fisheries Kasai Hyogo-Prefecture National Institute of FruitTree Science Fujimoto Tsukuba Ibaragi-Prefecture Japan

Cross-resistance, resistance mechanisms, and mode of inheritance of spinosad resistance were studied in the western flower thrip, Frankliniella occidentalis （Pergande）. Spinosad （naturalyte insecticide） showed low cross-resistance to prothiophos （organophosphorus insecticide） and chlorphenapyr （respiratory inhibitor） showed some cross-resistance to thiocyclam （nereistoxin）. The synergists PBO （piperonyl butoxide）, DEM （diethyl maleate）, and DEF （s,s,s-tributyl phosphorotrithioate） did not show any synergism on the toxicity of spinosad in the resistant strain （ICS）, indicating that metabolic- mediated detoxification was not responsible for the spinosad resistance, suggesting that spinosad may reduce sensitivity of the target site： the nicotinic acetylcholine receptor and GABA receptor. Following reciprocal crosses, dose-response lines and dominance ratios indicated that spinosad resistance was incompletely dominant and there were no maternal effects. The results of backcross showed that spinosad resistance did not fit a single-gene hypothesis, suggesting that resistance was influenced by several genes.

关键词： inheritance resistance spinosad synergism western flower thrip

Use of bionic inspired surfaces for aerodynamic drag reduction on motor vehicle body panels

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第7期12卷 543-551页

作者： Xiao-wen SONG Guo-geng ZHANG yun WANG shu-gen HU Department of Mechanical Engineering Zhejiang University Hangzhou 310027 China

Inspired by the successful applications of biological non-smoothness,we introduced bionic non-smooth surfaces as appendices into vehicle body design,aiming to further reduce aerodynamic *** size range of the non-smooth units with pits and grooves was determined according to our analysis with the mechanisms underlying non-smooth unit mediated aerodynamic drag *** bionic non-smooth units reported here were designed to adapt the structure of a given vehicle body from the point of boundary layer control that reduces the burst and the loss of turbulent kinetic *** engine cover lid and vehicle body cap were individually treated with the non-smooth units,and the treated vehicles were subjected to aerodynamic drag coefficient simulation tests using the computational fluid dynamics(CFD) analysis *** simulation results showed that,in comparison with smooth surfaces,properly designed non-smooth surfaces can have greater effects on drag *** mechanism underlying drag reduction mediated by non-smooth surfaces was revealed by further analyses,in which the effects of non-smooth and smooth surfaces were directly compared.

关键词： Computational fluid dynamics(CFD) Bionics Non-smooth surface Aerodynamic drag reduction Vehicle body

Simulating Study of Dynamic Load Spectra Identification Method of Machinery in Cepstrum Domain

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Journal of China University of Mining and Technology 2006年第1期16卷 22-24页

作者： HONG Cong-hua QIAO shu-yun WU Miao School of Mechanical and Electrical Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China Xuzhou Institute of Engineering Xuzhou Jiangsu 221008 China School of Mechanical Electronic and Information Engineering China University of Mining ＆ Technology Beijing 100083 China

Based on the platform of Matlab and the theory of digital signal processing, we propose a method in the cepstrum domain for dynamic load spectra identification of machinery. We demonstrate that the dynamic load spectra can be identified from the response signal of the system, based on cepstra. An ARMA model is built based on the harmonic retrieval by high-order spectra. The coefficients of a Green function are determined and the window width can be estimated. Finally the effectiveness of the method is validated by simulation results.

关键词： cepstrum dynamic load spectrum identification high-order spectra simulation