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CeO2/TiO2 Monolith Catalyst for the selective Catalytic Reduction of NOx with NH3： Influence of H2O and sO2

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Chemical Research in Chinese Universities 2016年第3期32卷 461-467页

作者： ZHANG fan TIAN Gang WANG Hongmei WANG Hongchang ZHANG Chen CUI Yutao HUANG Jiayu sHU Yun Research Center of Air Pollution Control Technology Chinese Research Academy of Environmental Sciences Beo'ing 100012 P. R. China

The influences of H2O and sO2 on CeO2/TiO2 monolith catalyst for the selective catalytic reduction（sCR） of NOx with NH3 were investigated. In the absence of sO2, H2O inhibited the sCR activity, which might be ascribed to the competitive adsorption of H2O and reactants such as NH3 and/or NOx. sO2 could promote the sCR activity of CeO2/TiO2 monolith catalyst in the absence of H20, while in the presence of H20 it speeded the deactivation. During the sCR reaction in sO2-containing gases, Ce（Ⅲ） sulfate species formed on the catalyst surface, resulting in the en- hancement of Bronsted acidity. This played a significant role in the enhanced sCR activity. However, in the presence of both H2O and sO2, a large amount of ammonium-sulfate salts formed on the catalyst surface, which resulted in the blocking of catalyst pores and deactivated the catalyst. In addition, the NOx conversion was more sensitive to gas hourly space velocity in the presence of H20 than in the absence of H20. The relatively high space velocity would result in a higher formation rate of ammonium-sulfate salts on per unit catalyst in the presence of H2O and sO2, which caused obvious deactivation of Ce/TiO2 monolith catalyst.

关键词： CeO2/TiO2 catalyst selective catalytic reduction(sCR) sulfur dioxide Water

Microtexture Evolution and Grain Boundary Character Distribution of Interstitial-Free steels With Moderate Levels of Cold Rolling Reductions

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Journal of Iron and steel Research International 2013年第12期20卷 47-52页

作者： YANG Jing-jing fan Li-xia JIA Juan WU Run sONG Xin-li JIANG Li-li school of Materials and Metallurgy Wuhan University of Science and Technology

High-strength interstitial-free steel sheets have very good deep drawability when processed to have { 111 } recrystallization texture. The microtexture evolution and grain boundary character distribution of interstitial-free steels as a function of moderate levels of cold rolling reductions were investigated by the metallographic microscopy and electron backscatter diffraction technique. The results showed that there was a close relationship between micro- texture and grain boundary character distribution for interstitial-free steel, especially the distribution and features of some specific types of coincident-site lattice boundaries. In addition, a-fiber texture was weakened to vanish while 7- fiber texture strengthened gradually as cold rolling reduction was increased from 20% to 75 % for cold rolled and an- nealed samples. Accordingly, increasing the rolling reduction from 20 % to 750% would lead to a significant increase in the proportion of ∑3 boundaries. Also, it was found that the microtexture of 20% cold rolled sample would induce a high frequency of ∑11 grain boundaries, but the microtexture of 75% cold rolled sample would produce more ∑7 and ∑17 grain boundaries. It was suggested that texture played a significant role in the formation of grain boundary character distribution.

关键词： interstitial-free steel mierotexture evolution grain boundary character distribution electron backscatter diffraction

A selective and sensitive Fluorescence Probe for se（IV） Based on Fluorescence Quenching of Gatifloxacin

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Chemical Research in Chinese Universities 2016年第5期32卷 736-741页

作者： LIU Qing HUAN Yanfu ZHENG Qingchuan FEI Qiang FEI Yanqun fan Qian FENG Guodong sHAN Hongyan College of Chemistry Jilin University Changchun 130021 P. R. China Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University Changchun 130021 P. R. China Changchun WeiersaiBiotec Pharmaceutical Co. Ltd. Changchun 130616 P. R. China Changchun Vocational Institute of Technology Changchun 130033 P. R. China

A novel high selective and sensitive fluorescence probe termed gatifloxacin was discovered based on fluorescence ＂on-off＂ phenomenon in the presence of se（IV）. In the Tris-HCl/acetonitrile（3：7, volume ratio, Tris-HCl 0.05 mol/L, pH=7.3） system, the fluorescence intensity of gatifloxacin was linearly decreased with the concentration increase of se（IV） in a range of 1.0×10-5--5.0×10-5 mol/L with a correlation coefficient of 0.9979（R2=0.9958） and in a range of 5.0×10-5--1.0 ×10-4 mol/L with a correlation coefficient of 0.9973（R2=0.9946）. The detection limit of se（IV） was 1.70×10-6mol/L.

关键词： Gatifloxacin Fluorescence probe Quenching selenium

Graphene-based Li-ion hybrid supercapacitors with ultrahigh performance

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Nano Research 2013年第8期6卷 581-592页

作者： Kai Leng fan Zhang Long Zhang Tengfei Zhang Yingpeng Wu Yanhong Lu Yi Huang Yongsheng Chen Key Laboratory of Functional Polymer Materials and Centre for Nanoscale science and Technology Institute of Polymer ChemistryCollege of Chemistry Nankai University Tianjin300071 China

There is a growing demand for hybrid supercapacitor systems to overcome the energy density limitation of existing-generation electric double layer capacitors （EDLCs）, leading to next generation-Ⅱ supercapacitors with minimum sacrifice in power density and cycle life. Here, an advanced graphene-based hybrid system, consisting of a graphene-inserted Li4Ti5O12 （LTO） composite anode （G-LTO） and a three-dimensional porous graphene-sucrose cathode, has been fabricated for the purpose of combining both the benefits of Li-ion batteries （energy source） and supercapacitors （power source）. Graphene-based materials play a vital role in both electrodes in respect of the high performance of the hybrid supercapacitor. For example, compared with the theoretical capacity of 175 mA-h.g-1 for pure LTO, the G-LTO nanocomposite delivered excellent reversible capacities of 207, 190, and 176 mA·1h·g-1 at rates of 0.3, 0.5, and 1 C, respectively, in the potential range 1.0-2.5 V vs. Li/Li＋; these are among the highest values for LTO-based nano- composites at the same rates and potential range. Based on this, an optimized hybrid supercapacitor was fabricated following the standard industry procedure; this displayed an ultrahigh energy density of 95 Wh·kg-1 at a rate of 0.4 C （2.5 h） over a wide voltage range （0-3 V）, and still retained an energy density of 32 Wh·kg-1 at a high rate of up to 100 C, equivalent to a full discharge in 36 s, which is exceptionally fast for hybrid supercapacitors. The excellent performance of this Li-ion hybrid supercapacitor indicates that graphene-based materials may indeed play a significant role in next-generation supercapacitors with excellent electrochemical performance.

关键词： graphene hybrid supercapacitor Li-ion battery supercapacitor

Effects of freeze-thaw cycle on engineering properties of loess used as road fills in seasonally frozen ground regions,North China

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Journal of Mountain science 2017年第2期14卷 356-368页

作者： LI Guo-yu MA Wei MU Yan-hu WANG Fei fan shan-zhi WU Ya-hu state Key Laboratory of Frozen soil Engineering Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of SciencesLanzhou 730000China

Compacted loess is widely used as fills of road embankments in loess regions of northern ***, densely-compacted loess can satisfy the requirements of embankment strength and postconstruction deformation. However, uneven subsidence, pavement cracks and other related damages can affect the integrity of loess subgrade after several years of operation,and even cause some hazards, especially in North China, where the strong freeze-thaw erosion occurs. In this study, cyclic freeze-thaw tests for both densely and loosely compacted loess samples were performed to determine the variation in engineering properties such as volume, void ratio, collapsible settlement,microstructure, and the related mechanisms were addressed. The experimental results showed that an obvious water migration and redistribution occurred within the samples during freeze-thaw cycles. Ice lenses and fissures could be identified in the upper frozen layers of the samples. After freeze-thaw cycles,the dry densities of the upper layers of samples changed significantly due to strong freeze-thaw erosion. The dry densities decreased for the dense sample and increased for the loose sample. It can be found that dense samples become loose, while loose samples became dense with the increasing number of freeze-thaw cycles. Their related void ratios changed reversely. Both void ratios tended to fall into a certain range, which verified the concept of a residual void ratio proposed by Viklander. The loosening process of densely compacted samples involves the formation of large pores, volume increase and density reduction as well as the related changes in mechanical properties because freeze-thaw cycles may be important contribution to problems of loess road *** effects of freeze-thaw cycles, therefore,should be taken into account in selecting loess parameters for the stability evaluation of road embankment in seasonally frozen ground regions.

关键词： Loess Freeze-thaw cycle Frost heave Thaw settlement Road engineering

Thermostable Nitrogen-Doped HTiNbO5 Nanosheets with a High Visible-Light Photocatalytic Activity

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Nano Research 2011年第7期4卷 635-647页

作者： Zheng Zhai Yucheng Huang Lin Xu Xiaoyan Yang Chenhui Hu Lihong Zhang Yining fan Wenhua Hou Key Laboratory of Mesoscopic Chemistry of MOE School of Chemistry and Chemical Engineering Nanjing University Nanjing210093 China

Nitrogen-doped HTiNbO5 nanosheets have been successfully synthesized by first exfoliating layered HTiNbO5 in tetrabutylammonium hydroxide （TBAOH） to obtain HTiNbO5 nanosheets and then heating the nanosheets with urea. The resulting samples were characterized by X-ray diffraction （XRD）, transmission electron microscopy （TEM）, scanning electron microscopy （sEM）, energy-dispersive X-ray （EDX）, X-ray photoelectron spectroscopy （XPs）, UV-vis spectroscopy and N2 adsorption-desorption measurements. It was found that N-doping resulted in a much higher thermostability of the layered structure, intrinsic bandgap narrowing and a visible light response. The doped nitrogen atoms were mainly located in the interstitial sites of TiNbOs- lamellae and chemically bound to hydrogen ions. Compared with N-doped HTiNbOs, N-doped HTiNbO5 nanosheets had a much larger specific surface area and richer mesoporosity due to fee rather loose and irregular arrangement of fitanoniobate nanosheets. Both N-doped layered HTiNbOs and HTiNbO5 nanosheets showed a very high visible-light photocatalytic activity for the degradation of rhodamine B （RhB） aqueous solution. Moreover, due to the considerably larger surface area, richer mesoporosity and stronger acidity, N-doped HTiNbO5 nanosheets had an even higher activity than N-doped HTiNbOs, although the latter had a stronger absorption in the visible region. The dye molecules were mainly degraded to aliphatic organic compounds and partially mineralized to CO2 and/or CO, rather than being simply decolorized. The effect of photosensitization was insignificant and RhB was degraded mainly via the typical photocatalytic reaction routes. Two different reaction routes for the photodegradation of RhB under visible light irradiation over N-doped HTiNbO5 nanosheets have been proposed. The present method can be extended to a large number of layered metal oxides that have the characteristics of intercalation and exfoliation, thus providing new opportunities for the f

关键词： Layered titanoniobate nanosheets N-doping photodegradation visible light

synthesis and Biological Activities of Novel 1,2,4-Triazole Derivatives Containing 1,2,3-Thiadiazole Ring

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Chemical Research in Chinese Universities 2014年第3期30卷 390-395页

作者： LI Yuedong MAO Wutao fan Zhijin LI Juanjuan fanG Zhen JI Xiaotian ZONG Guangning LI Fengyun state Key Laboratory of Elemento-organic Chemistry Nankai University Tianjin 300071 P. R. China College of Chemistry and Pharmacy Engineering Nanyang Normal University Nanyang 473061 P R. China Collaborative Innovation Center of Chemical science and Engineering(Tianjin) Nankai University Tianjin 300071 P. R. China

A series of novel 1,2,4-triazole derivatives containing 1,2,3-thiadiazole ring was designed and synthesized. Their structures were confirmed by IR, 1^H NMR, high resolution mass spectrometer（HRMs） and electrospray ionization-mass spectromcter（EsI-Ms） combined with melting points and elemental analysis. Preliminary bioassays indi- cate that these compounds exhibit good insecticidal activity against Aphis laburni at 100 μg/mL, especially compound 6b shows mortality of no less than 95%. Most of the compounds show good activities against tobacco mosaic virus（TMV） with different modes in vivo at 100 μg/mL. Compound 6d standed out, showing a good insecticidal activity and very high induction effects against TMV in vivo. Collectively, our data demonstrate a new strategy for insect and virus control.

关键词： 1,2,3-Thiadiazole 1,2,4-Triazole Insecticidal activity Anti-tobacco mosaic virus(TMV) activity

With senior Women Officials

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Women of China 1997年第12期 17-18页

作者： fan sUJUAN fan YI

IN early May when flowers were blooming, 37 senior women officials of 16 nationalities from 14 provinces and autonomous regions were invited by Hong Kong Pei Hua Education Foundation Limited to attend the seventh seminar for the senior Officials of the Minorities’ Autonomous Prefectures in China. I was also invited as an ethnic women’s affairs worker at the All-China Women’s Federation. This was the first time I had been with s many senior women officials. They didn’t know each other, yet the first day they met they sat together, introducing

关键词： With senior Women Officials

Green and efficient dry gel conversion synthesis of sAPO-34 catalyst with plate-like morphology

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Petroleum science 2017年第1期14卷 203-213页

作者： Chun-Yu Di Xiao-Feng Li Ping Wang Zhi-Hong Li Bin-Bin fan Tao Dou College of Chemistry and Chemical Engineering Taiyuan University of Technology CNPC Key Laboratory of Catalysis College of Chemical Engineering China University of PetroleumBeijing

sAPO-34 catalyst with plate-like morphology was designed and synthesized for the first time, by the dry gel conversion method using cheap triethylamine as a structure-directing agent assisted with seed suspension containing nanosheet-like sAPO-34 seed. The latter played an important role in formation of sAPO-34 （CHA-type） with plate-like morphology. In addition, the yield of the product in the synthesis system containing seed suspension reached 97%, 15% higher than that obtained in the corre- sponding synthesis system without the seed suspension. Meanwhile, the plate-like sAPO-34 catalysts synthesized by this method exhibited higher selectivity to light olefins and longer lifetime in methanol-to-olefins （MTO） reaction than the traditional cubic sAPO-34 catalyst. This work provides a new technical route for green and efficient synthesis of sAPO-34 catalysts with improved MTO performance.

关键词： sAPO-34 Dry gel conversion Greenchemistry seed suspension Plate-like - MTO