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In situ adsorption-catalysis system for the removal of o-xylene over an activated carbon supported Pd catalyst

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Journal of Environmental sciences 2009年第7期21卷 985-990页

作者： HUANG Shaoyong, ZHANG Changbin, HE Hong Research Center for Eco-Environmental sciences, chinese academy of sciences, {2. 100085, china. [a]Research Center for Eco-Environmental sciences Chinese Academy of Sciences Beijing 100085 China

An activated carbon （AC） supported Pd catalyst was used to develop a highly efficient in situ adsorption-catalysis system for the removal of low concentrations of o-xylene. In this study, three kinds of Pd/AC catalysts were prepared and tested to investigate the synergistic efficiency between adsorption and catalysis for o-xylene removal. The Pd/AC catalyst was first used as an adsorbent to concentrate dilute o-xylene at low temperature. After saturated adsorption, the adsorbed o-xylene was oxidized to CO2.and H2. by raising the temperature of the catalyst bed. The results showed that more than 99% of the adsorbed o-xylene was completely oxidized to CO2.over a 5% Pd/AC catalyst at 140℃. Brunauer-Emmett-Teller （BET） analysis, scanning electron microscopy （SEM）, temperatureprogrammed desorption （TPD）, and temperature-programmed oxidation （TPO） were applied to investigate the physical properties of o-xylene adsorption-desorption and the in situ adsorption-catalysis activity of the AC support and Pd/AC catalyst. A synergistic relationship between the AC support and the active Pd species for the removal of low concentrations of o-xylene was established.

关键词： in situ adsorption-catalysis Pd/AC volatile organic compounds

Exsolution of ilmenite and Cr-Ti magnetite from olivine of garnet-wehrlite

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Science china Earth sciences 2005年第9期48卷 1368-1376页

作者： LIU Xiangwen1,2. JIN Zhenmin1,3, QU Jing2.& WANG Lu2.1. State Key laboratory of Geological Processes and Mineral Resources, china University of Geo{2., Wuhan 430074, china 2. Graduate School of china University of Geo{2., Wuhan 430074, china 3. Faculty of Earth {2., china University of Geo{2., Wuhan 430074, china 1. State Key laboratory of Geological Processes and Mineral Resources China University of Geosciences 430074 Wuhan China 2. Graduate School of china University of Geosciences 430074 Wuhan China 3. Faculty of Earth sciences China University of Geosciences 430074 Wuhan China

Exsolution of rod-like ilmenite (Ilm) and Cr-Ti magnetite (Mt) have been found in olivine of garnet-wehrlite from the core of chinese Continental sciences Drilling (CCSD). Their composition, morphology, crystal structure and their topotaxies with host olivine have been studied in detail by the transmission {2. microscopy (TEM) and {2. probe microanaly- sis (EPMA) technique. It shows that rod-like Ilm exsolution reported in this paper has similar characteristic with that of Alpe Arami olivine, while Cr-Ti magnetite exsolution mentioned in this paper has large discrepancy with chromite exsolution in Alpe Arami olivine. These observations suggest that both of the exsolutions found in this paper should be solid solution phases in β-olivine at their first period, then experiencing decomposition of solid solution and therefore forming Ilm and Cr-Ti magnetite exsolution with the pressure decreasing. So, this garnet-wehrlite perhaps had been ever located in mantle transition zone with a minimum depth of 300 km.

关键词： garnet-wehrlite, ilmenite, magnetite, exsolution, CCSD.

Transmission electron microscopy Investigation of the Ar^+ Ion Irradiation Effect in Semiconductor GaAs

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Wuhan University Journal of Natural sciences 1998年第1期3卷 35-40页

作者： Yang Xiangxiu Wang Renhui Yan Heping Zhang Ze Wuhan Univ Wuhan China

Room temperature irradiation effect of GaAs compound semiconductor by 100 keV Ar+ ions has been systematically studied by means of transmission electron microscopy. The dose dependenceoof the Ar+ ion irradiation and room temperature annealing effects have been investigated. The experimental results show that the structure of GaAs transforms from perfect crystalline through weakly and severely damaged crystalline to amorphous states with the increase of the irradiation dose and the damaged states are changed during room temperature annealing.

关键词： GaAs irradiation effect transmission electron microscopy

Surface effects of monolayer-protected gold nanoparticles on the redox reactions between ferricyanide and thiosulfate

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Science china Chemistry 2005年第5期48卷 424-430页

作者： LI Di1, SUN Chunyan1, HUANG Yunjie1, LI Jinghong1,2.& CHEN Shaowei3 1. State Key laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, chinese academy of sciences, Changchun 13002.,{2. 2. Department of Chemistry, Tsinghua University, beijing 100084,{2. 3. Department of Chemistry, University of California, Santa Cruz, Santa Cruz, CA 95064, USA 1. State Key laboratory of Electroanalytical Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences 130022 Changchun China 2. Department of Chemistry Tsinghua University 100084 Beijing China 3. Department of Chemistry University of California 95064 Santa Cruz Santa Cruz CA USA

electron transfer through the self-assembled monolayers (SAMs) on gold nanopar-ticles is investigated by using the monolayer protected gold nanoclusters (MPCs) as elec-tron-transfer mediators. 3-Mercaptopropionic acid (MPA) and 11-meraptoundecanoic acid (MUA) MPCs were employed to catalyze the redox reaction between potassium ferricyanide and sodium thiosulfate. The catalytic mechanism was proposed that the MPCs act as diffusing elec-tron-mediators and electron transfers to and from the MPCs surface. Therefore the electron transfer rate through the capping layers would be proportional to the MPCs catalyzed reaction rate, which was monitored by the UV absorbance of ferricyanide. The calculated apparent rate constant was orders of magnitude smaller than that of the maximum of tunneling current, which was attributed to the splited energy level of the nanoscale particles.

关键词： electron transfer, three-dimensional self-assembled monolayers, redox reaction, electron transfer mediator, surface effect.

ECSTM study of adsorption of C_(60),C_(70),C_(86) and Y@C_(82. on Au(111)

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Science china Chemistry 2010年第8期53卷 1705-1710页

作者： SU GuiJin1,JIA ManKe1,GAN LiHua2.& SHI RuiFang1 1State Key laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental sciences,{2. academy of sciences,beijing 100085,china 2.chool of Chemistry and Chemical Engineering,Southwest University,Chongqing 400715,china 1. State Key laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental sciences Chinese Academy of Sciences Beijing 100085 China2. School of Chemistry and Chemical Engineering Southwest University Chongqing 400715 China

The adsorption of a variety of fullerenes (C60,C70,C86,Y@C82. on Au(111) electrode surfaces was comprehensively investigated in 0.1 M HClO4 by electrochemical scanning tunneling microscopy (ECSTM).In the ordered C60's adlayer,C60 molecules formed either (2.1/3) × 2.3～(1/3))or "in-phase" *** high resolution STM image shows that the C60 cage is not simply round but shows a bifurcated *** adsorption orientation of C60 on Au(111) is tentatively *** the ordered C70's adlayer,the perpendicular fullerene molecules are the main adsorption mode and form (2.3～(1/3) × 2.3～(1/3)) ***,for C86 and Y@C82.the ordered adlayer could not be obtained on Au(111) under the present *** differences may be due to the different molecular shapes and sizes,and the encapsulated metal atom which affects the lattice matches with the *** adsorption of fullerene molecules on Au(111) from disorder to order could be tuned simply by steering the dimensional sizes or shapes of the fullerenes used.

关键词： C60 C70 C86 Y@C82 ECSTM Au(111)

Effect of Low Energy electron Exposure on Ion Scattering Spectroscopy

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chinese Chemical Letters 2003年第10期14卷 1058-1061页

作者： Li Mei QIU, Fen LIU, Liang Zhong ZHAO Institute of Chemistry, chinese academy of sciences, beijing 100080 Institute of Chemistry Chinese Academy of Sciences

The effect of low energy electron (LEE) exposure on ISS, including on the sputter peak and scatter peak as well as on ion neutralization, has been investigated for different samples. Some new results are discussed.

关键词： Ion scattering spectroscopy (ISS) charge neutralization ion neutralization.

Organic Solvents Mediate Self-assembly of GAV-9 Peptide on Mica Surface

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Acta Biochimica et Biophysica Sinica 2007年第4期39卷 285-289页

作者： Hai LI~(1,3) Feng ZHANG~1 Yi ZHANG~1* Jianhua HE~1 Jun HU~(1,2. 1 Shanghai Institute of Applied Physics,chinese academy of {2.,Shanghai 2.1800,china 2.Bio-X Life {2. Research Center.College of Life Science and Biotechnology,Shanghai Jiaotong University,Shanghai 2.0030,china 3 Graduate School of the chinese academy of sciences,beijing 100049,china Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800 China Graduate School of the chinese academy of sciencesbeijing 100049 China Bio-X Life sciences Research Center College of Life Science and Biotechnology Shanghai Jiaotong UniversityShanghai 200030 China

Self-assembly of peptides into fibrils and other morphologies has attracted much attention inmany fields,especially in nanofabrication,pathology and *** this paper,self-assembly of GAV-9peptide in organic solvents,ethanol and acetone,was investigated using atomic force microscopy(AFM)and attenuated total reflectance-Fourier transform infrared spectroscopy(ATR-FTIR).The results indicatedthat GAV-9 self-assembled into various nanostructures in both solvents after deposited and evaporated *** with β-sheet conformation were observed in both solvents when the peptide concentrationwas higher than 2.0 μ***,ordered fibrils with β-sheet conformation were formed in ethanol,butnot in acetone,with a peptide concentration ranging from 7 μM to 2. μ*** attribute the formation ofvarious nanostructures to the different physicochemical properties of the polar organic solvents on the self-assembly of GAV-9 peptide.

关键词： self-assembly GAV-9 peptide organic solvents ATR-FTIR AFM

Effects of crystallization fractions on mechanical properties of Zr-based metallic glass matrix composites

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Science china(Physics,Mechanics & Astronomy) 2010年第3期53卷 424-429页

作者： QIU ShengBao1,2. YAO KeFu1 & GONG Pan1 1 KLAMPT, Department of Mechanical Engineering, Tsinghua University, beijing 100084, china 2.Institute of Industry Technology, Guangzhou &{2., Guangzhou 511458, china 1. KLAMPT Department of Mechanical Engineering Tsinghua University Beijing 100084 China2. Institute of Industry Technology Guangzhou & Chinese Academy of Sciences Guangzhou 511458 China

The Zr41Ti14Cu12.5Ni10Be2..5 (at.%) bulk metallic glass composites with various crystallization fractions were prepared by pretreating the bulk metallic glassy samples with pulsing current, and then by isothermal annealing at near initial crystallization temperature for different periods of time. The precipitations and crystallization fractions were studied by X-ray diffraction (XRD) and differential scanning calorimetry (DSC), and their effects on mechanical properties of the composite were studied by microhardness, uniaxial compression test and scanning electron microscopy (SEM). The experimental results show that the primary precipitate is quasicrystalline phase and other metastable phases including Be2.r, Zr2.u and FCC would precipitate subsequently. In the initial crystallization process, in which the crystallization fraction increases from 0 to 8.2., both fracture strength and plastic strain increase, with the maximum plastic strain up to 6.4%. When the crystallization fraction is larger than 8.2., the fracture strength and the plastic strain decrease sharply. Furthermore, the alloy with low crystallization fraction is fractured by shearing, while for high crystallization fraction it is fractured by splitting and cleavage. The results show that the mechanical properties of the glassy alloy could be optimized by controlling the processing parameters.

关键词： bulk metallic glass pulsing current crystallization fraction plasticity shear band

Application of cathodoluminescence to zircon in FEG-ESEM

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Progress in Natural Science:Materials International 2006年第9期16卷 919-924页

作者： CHEN Li , XU Jun and SU Li (electron microscopy {2., School of Physics, Peking University, beijing 100871, china Geology Experimental Center, china University of Geoscience, beijing 100083, china) electron microscopy {2. School of Physics Peking University Beijing 100871 China Geology Experimental Center China University of Geoscience Beijing 100083 China

Cathodoluminescence (CL) image analysis of zircon is a key step of mineral micro-area compositional investigation and U-(Th)-Pb dating. We introduce a system consisting of field emission ESEM and high performance cathodoluminescence. This system has obvious advantages in imaging resolution and CL spectrum. We acquired some zircon CL images and spectra to demonstrate the ability of this system. Our results show that this system has a great potential application to characterize and identify the genesis of zircon.

关键词： zircon cathodoluminescence ESEM.