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2014 International Conference on Artificial,Intelligence and Software Engineering(AISE 2014)

作者： Xiao SUN Cheng-cheng LI Yong-an YU Xiao-li NAN Anhui Province Key Laboratory of Affective Computing and Advanced Intelligent Machine School of Computer and Information Hefei University of Technology Dalian Informedia Electronic Co. Ltd. Dalian University of Technology AAVIC Jiangxi Hongdu Aviation Industry Group Corporation Limited

This paper presents a multi-modality feature extraction method based sentiment classification for Chinese microblogging. Human sentiment in microblogging is divided into three categories(positive, neutral, negative). Compared with traditional Chinese microblogging sentiment classification approaches, the method adopts the characteristics of microblogging social environment modality(including microblogging comments and relationships between commentators and micro-bloggers), while it extracts the microblogging text feature. The paper integrates the above two modality features and improve the performance of sentiment classification. At last, we model the feature sets by adopting fuzzy SVM model. The experimental results demonstrate the performance of the method on sentiment classification.

关键词： Emotion analysis Sentiment classification Multi-modality Sentiment fuzzy SVM

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A novel multi-fidelity coupled simulation method for flow systems

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Chinese Journal of Aeronautics 2013年第4期26卷 868-875页

作者： Wang Peng Zheng Yun Zou Zhengping Qi Lei Zhou Zhixiang National Key Laboratory of Science & Technology on Aero-Engine Aero-thermodynamics School of Energy and Power Engineering Beihang University Aeroengine Numerical Simulation Research Center School of Energy and Power Engineering Beihang University Chinese Aviation Powerplant Research Institute

For the numerical simulation of flow systems with various complex components, the traditional one-dimensional （1D） network method has its comparative advantage in time consuming and the CFD method has its absolute advantage in the detailed flow capturing. The proper coupling of the advantages of different dimensional methods can strike balance well between time cost and accuracy and then significantly decrease the whole design cycle for the flow systems in modern machines. A novel multi-fidelity coupled simulation method with numerical zooming is developed for flow systems. This method focuses on the integration of one-, two-and three-dimensional codes for various components. Coupled iterative process for the different dimensional simulation cycles of sub-systems is performed until the concerned flow variables of the whole system achieve convergence. Numerical zooming is employed to update boundary data of components with different dimen-sionalities. Based on this method, a highly automatic, multi-discipline computing environment with integrated zooming is developed. The numerical results of Y-Junction and the air system of a jet engine are presented to verify the solution method. They indicate that this type of multi-fidelity simulationmethod can greatly improve the prediction capability for the flow systems.

关键词： Complex flow system Coupling Jet engine Multi-fidelity Zooming

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Linking the environmental loads to the fate of PPCPs in Beijing: Considering both the treated and untreated wastewater sources

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Environmental pollution (Barking, Essex : 1987) 2015年 202卷 153-9页

作者： Bin Wang Guohua Dai Shubo Deng Jun Huang Yujue Wang Gang Yu State Key Joint Laboratory of Environmental Simulation and Pollution Control School of Environment Tsinghua University Beijing 100084 China Collaborative Innovation Center for Regional Environmental Quality Tsinghua University Beijing 100084 China Tsinghua-Veolia Joint Research Center for Advanced Environmental Technology Tsinghua University Beijing 100084 China. Electronic address: thuwb@***. Tsinghua-Veolia Joint Research Center for Advanced Environmental Technology Tsinghua University Beijing 100084 China. Collaborative Innovation Center for Regional Environmental Quality Tsinghua University Beijing 100084 China. Beijing Key Laboratory of Emerging Organic Contaminants Tsinghua University Beijing 100084 China.

The environmental loads of pharmaceutical and personal care products (PPCPs) in Beijing were estimated from direct discharge of untreated wastewater and WWTP treated effluent. The annual environmental loads of 15 PPCP components ranged from 16.3 kg (propranolol) to 9.85 tons (caffeine). A fugacity model was developed to successfully estimate the PPCP pollution based on the estimated environmental load. The modeled results approximated the observed PPCP concentrations in Beijing. The untreated wastewater contributed significantly to PPCP pollution in Beijing, ranging from 46% (propranolol) to 99% (caffeine). The total environmental burden of target PPCPs ranged from 0.90 kg (propranolol) to 536 kg (caffeine). Water is the most important media for the fate of PPCPs. Monte Carlo-based concentration distributions of PPCPs are consistent with the observed results. The most important way to reduce the PPCP pollution is to both improve wastewater collection rate and adopt deep treatment technologies.

关键词： Environmental load Fugacity model Personal care product Pharmaceutical Sensitivity analysis Uncertainty analysis

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Detwinning-induced reduction in ductility of twinned copper nanowires

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Chinese Science Bulletin 2013年第6期58卷 684-688页

作者： ZHANG JunJie XU FangDa YAN YongDa SUN Tao Center for Precision Engineering Harbin Institute of Technology Interdisciplinary Centre for Advanced Materials Simulation(ICAMS) Ruhr University BochumUniversit tsstr Key Laboratory of Micro-systems and Micro-structures Manufacturing of Ministry of Education Harbin Institute of Technology

Detwinning is a unique deformation mechanism of nanotwinned metals with twin lamellae thickness down to a few *** this work we investigate the impact of detwinning mechanism on the tensile ductility of twinned Cu nanowires containing high density of parallel twin boundaries by means of molecular dynamics *** results show that the fracture strain of twinned Cu nanowires has a strong dependence on twin boundary spacing,resulting from the competition between individual deformation *** for the twinned Cu nanowires containing the thinnest twin lamellaes,the dominant detwinning mechanism leads to a significant reduction in the tensile *** is found that detwinning originates from twin boundary migration,which is a result of the glide of lattice partial dislocations on the twin *** work advances our fundamental understanding of the twin boundary-related mechanical properties of twinned metallic nanowires.

关键词：金属纳米线孪晶界延展性分子动力学模拟铜诱导变形机制片层厚度

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Parton distribution amplitudes of light vector mesons

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Physical Review D 2014年第1期90卷 014011-014011页

作者： Fei Gao Lei Chang Yu-Xin Liu Craig D. Roberts Sebastian M. Schmidt Department of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University Beijing 100871 China Collaborative Innovation Center of Quantum Matter Beijing 100871 China CSSM School of Chemistry and Physics University of Adelaide Adelaide SA 5005 Australia Center for High Energy Physics Peking University Beijing 100871 China Physics Division Argonne National Laboratory Argonne Illinois 60439 USA Institute for Advanced Simulation Forschungszentrum Jülich and JARA D-52425 Jülich Germany

A rainbow-ladder truncation of QCD’s Dyson-Schwinger equations is used to calculate ρ- and ϕ-meson valence-quark (twist-two parton) distribution amplitudes (PDAs) via a light-front projection of their Bethe-Salpeter wave functions, which possess S- and D-wave components of comparable size in the meson rest frame. All computed PDAs are broad concave functions, whose dilation with respect to the asymptotic distribution is an expression of dynamical chiral symmetry breaking. The PDAs can be used to define an ordering of valence-quark light-front spatial extent within mesons: this size is smallest within the pion and increases through the ⊥ polarization to the ∥ polarization of the vector mesons; effects associated with the breaking of SU(3)-flavor symmetry are significantly smaller than those associated with altering the polarization of vector mesons. Notably, the predicted pointwise behavior of the ρ-meson PDAs is in quantitative agreement with that inferred recently via an analysis of diffractive vector-meson photoproduction experiments.

关键词： MESONS QUARKS PARTONS QUANTUM chromodynamics BETHE-Salpeter equation PIONS POLARIZATION (Nuclear physics) WAVE functions

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Zero mode in a strongly coupled quark gluon plasma

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Physical Review D 2014年第7期89卷 076009-076009页

作者： Fei Gao Si-Xue Qin Yu-Xin Liu Craig D. Roberts Sebastian M. Schmidt Department of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University Beijing 100871 China Collaborative Innovation Center of Quantum Matter Beijing 100871 China Institut für Theoretische Physik Johann Wolfgang Goethe University Max-von-Laue-Strasse 1 D-60438 Frankfurt am Main Germany Center for High Energy Physics Peking University Beijing 100871 China Physics Division Argonne National Laboratory Argonne Illinois 60439 USA Institute for Advanced Simulation Forschungszentrum Jülich and JARA D-52425 Jülich Germany

In connection with massless two-flavor QCD, we analyze the chiral symmetry restoring phase transition using three distinct gluon-quark vertices and two different assumptions about the long-range part of the quark-quark interaction. In each case, we solve the gap equation, locate the transition temperature Tc, and use the maximum entropy method to extract the dressed-quark spectral function at T>Tc. Our best estimate for the chiral transition temperature is Tc=147±8 MeV, and the deconfinement transition is coincident. For temperatures markedly above Tc, we find a spectral density that is consistent with those produced using a hard thermal loop expansion, exhibiting both a normal and plasmino mode. On a domain T∈[Tc,Ts], with Ts≃1.5Tc, however, with each of the six kernels we considered, the spectral function contains a significant additional feature. Namely, it displays a third peak, associated with a zero mode, which is essentially nonperturbative in origin and dominates the spectral function at T=Tc. We suggest that the existence of this mode is a signal for the formation of a strongly coupled quark-gluon plasma and that this strongly interacting state of matter is likely a distinctive feature of the QCD phase transition.

关键词： QUARK-gluon plasma PARTICLES (Nuclear physics) -- Flavor QUANTUM chromodynamics TRANSITION temperature QUARK-quark interactions PHASE transformations (Physics)

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Sulfur removal property of activated-char-supported Fe-Mo sorbents for integrated cleaning of hot coal gases

Sulfur removal property of activated-char-supported Fe-Mo so...

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作者： Yu, Jianglong Yin, Fengkui Wang, Shaoyan Chang, Liping Gupta, Sushil Key Laboratory of Coal-Based Fuels for Aviation School of Power and Energy Engineering Shenyang Aerospace University Shenyang 110136 China Key Laboratory of Advanced Coal and Coking Technology Liaoning Province School of Chemical Engineering University of Science and Technology Liaoning Anshan Liaoning 114051 China Key Laboratory of Coal Science and Technology Ministry of Education and Shanxi Province Taiyuan University of Technology Taiyuan 030024 China Centre for Sustainable Materials Research and Technology University of New South Wales Sydney NSW 2052 Australia

An integrated hot coal gas cleaning process is proposed with emphasis on simultaneous removal of multiple impurities including sulfur containing species, NOx precursors, mercury and tarry materials. Acti-vated- char-supported sorbents were synthesized by gasifying Fe and Mo impregnated Chinese lignite coal in steam (15%, vol) at 1100 K for 15 min. Sulfur removal properties of the sorbent samples were examined by sulfidation experiments using simulated coal gases (with 4700 ppmv H2S and 470 ppmv COS) at a space velocity of 1000 h-1 using a fixed-bed quartz reactor at the temperature range of 673-873 K. The SEM with EDS and XRD were used to examine the physical and chemical changes in the sorbents during sulfidation. The active metal oxides components were dispersed in the char matrix as nanosize particles resulting in a high reactivity of the sorbents towards H2S and COS contained in coal gases. Under the conditions in this study, the sorbents can effectively remove H2S and COS from the simulated coal gases with high efficiency. Sulfur removal is influenced by the level of iron-loading. The presence of Mo along with Fe in the char-supported sorbents can significantly increase the desulfurization efficiency. © 2010 Elsevier Ltd. All rights reserved.

关键词： Desulfurization

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Unveiling formation mechanism of carcinogenic N-nitrosodimethylamine in ozonation of dimethylamine: a density functional theoretical investigation

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Journal of hazardous materials 2014年 279卷 330-5页

作者： Siyu Zhang Gang Yu Jingwen Chen Bin Wang Jun Huang Shubo Deng State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment POPs Research Center Tsinghua University Beijing 100084 China Veolia Environment Joint Research Center for Advanced Technology Tsinghua University Beijing 100084 China. Veolia Environment Joint Research Center for Advanced Technology Tsinghua University Beijing 100084 China. Electronic address: yg-den@***. Key Laboratory of Industrial Ecology and Environmental Engineering (MOE) School of Environmental Science and Technology Dalian University of Technology Dalian 116024 China.

Recent studies found that ozonation of organic pollutants with dimethylamino groups produces N-nitrosodimethylamine (NDMA) that is highly carcinogenic to humans. However, the formation mechanism of NDMA remains inexplicit, and previously proposed mechanisms are inconsistent with experimental observations. In this study, the formation mechanism of NDMA in ozonation was explored by density functional theory (DFT) calculations, with dimethylamine (DMA) as a model compound. By calculating Gibbs energies and energy barriers, formation of NDMA in ozonation of DMA was observed to proceed through a hydroxylamine mechanism. The calculation results show that hydroxylamine is generated through DMA reacting with hydroxyl radicals (HO•) formed from hydrolysis of ozone. DMA reacting with hydroxylamine can produce unsymmetrical dimethylhydrazine (UDMH), a well-known NDMA precursor. Transformation of UDMH to NDMA is mainly induced by ozone or HO• rather than dissolved oxygen proposed previously. The reaction of DMA and hydroxylamine is pH dependent, with energy barriers increasing from neutral pH to the second pKa of hydroxylamine and then decreasing. This is in accordance with the experimentally observed pH dependence of NDMA yield in ozonation, indicating that the hydroxylamine mechanism is responsible for the NDMA formation in ozonation.

关键词： Density functional theory Dimethylamine Hydroxylamine N-nitrosodimethylamine Ozonation

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Enhancing charge harvest from microbial fuel cells by controlling the charging and discharging frequency of capacitors

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Bioresource technology 2013年 146卷 812-815页

作者： Shiting Ren Xue Xia Lulu Yuan Peng Liang Xia Huang State Key Joint Laboratory of Environment Simulation and Pollution Control THU-VEOLIA Environment Joint Research Center for Advanced Environmental Technology School of Environment Tsinghua University Beijing 100084 PR China. State Key Joint Laboratory of Environment Simulation and Pollution Control THU-VEOLIA Environment Joint Research Center for Advanced Environmental Technology School of Environment Tsinghua University Beijing 100084 PR China. Electronic address: liangpeng@***. State Key Joint Laboratory of Environment Simulation and Pollution Control THU-VEOLIA Environment Joint Research Center for Advanced Environmental Technology School of Environment Tsinghua University Beijing 100084 PR China. Electronic address: xhuang@***.

Capacitor is a storage device to harvest charge produced from microbial fuel cells (MFCs). In intermittent charging mode, the capacitor is charged by an MFC first, and then discharged through an external resistance. The charge harvested by capacitor is affected by the charging and discharging frequency. In the present study, the effect of the charging and discharging frequency on charge harvest was investigated. At the switching time (ts) of 100 s, the average current over each time segment reached its maximum value (1.59 mA) the earliest, higher than the other tested conditions, and the highest COD removal (63%) was also obtained, while the coulombic efficiency reached the highest of 67% at the ts of 400 s. Results suggested that lower ts led to higher current output and COD removal, but appropriate ts should be selected in consideration of charge recovery efficiency.

关键词： Capacitor Charge harvest Charging and discharging frequency Coulombic efficiency Microbial fuel cell

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Pharmaceuticals and personal care products in the aquatic environment in China: a review

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Journal of hazardous materials 2013年 262卷 189-211页

作者： Qingwei Bu Bin Wang Jun Huang Shubo Deng Gang Yu School of Environment THU-VEOLIA Joint Research Center for Advanced Environmental Technology Tsinghua University State key Joint Laboratory of Environment Simulation and Pollution Control Beijing 100084 PR China. Electronic address: qingweibu@***.

Pharmaceuticals and personal care products (PPCPs) have been detected as contaminants of emerging concern ubiquitously in the aquatic environment in China and worldwide. A clear picture of PPCP contamination in the Chinese aquatic environment is needed to gain insight for both research and regulatory needs (e.g. monitoring, control and management). The occurrence data of 112 PPCPs in waters and sediments in China has been reviewed. In most cases, the detected concentration of these PPCPs in waters and sediments were at ng/L and ng/g levels, which were lower than or comparable to those reported worldwide. A screening level risk assessment (SLERA) identified six priority PPCPs in surface waters, namely erythromycin, roxithromycin, diclofenac, ibuprofen, salicylic acid and sulfamethoxazole. The results of SLERA also revealed that the hot spots for PPCP pollution were those river waters affected by the megacities with high density of population, such as Beijing, Tianjin, Guangzhou and Shanghai. Limitations of current researches and implications for future research in China were discussed. Some regulatory issues were also addressed.

关键词： ACR Antibiotics CIP CLOA CTM DIC EDCs ERY ERY-H(2)O GEM IBU MDL MECs NAP ND NOECs NOR OFL OTC PCPs PNECs PPCPs ROX RQs SALA SD SLERA SMX SMZ Screening level risk assessment Sediment Surface water TCC TCS TET TMP TYL USA USEPA United States Environmental Protection Agency United States of America WWTPs acute-to-chronic ratio ciprofloxacin clarithromycin clofibric acid diclofenac endocrine disrupting chemicals erythromycin erythromycin-H(2)O gemfibrozil ibuprofen measured environmental concentrations method detection level naproxen no observed effect concentrations norfloxacin not detected ofloxacin oxytetracycline personal care products pharmaceuticals and personal care products predicted no effect concentrations risk quotients roxithromycin salicylic acid screening level ecological risk assessment sulfadiazine sulfamethazine sulfamethoxazole tetracycline triclocarban triclosan trimethoprim tylosin wastewater treatment plants

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