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TiO_2-Supported binary Metal Oxide Catalysts for Low-temperature Selective Catalytic Reduction of NO_x with NH_3

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Chemical Research in Chinese Universities 2008年第5期24卷 615-619页

作者： WU bi-jun LIU xiao-qin xiao Ping WANG Shu-gang Chemical Engineering Institute Nanjing University of Technology Nanjing 210009 P. R. China State Power Environmental Protection Research Institute of China Guodian Corporation Nanjing 210031 P. R. China

binary metal oxide（MnOx-A/TiO2）catalysts were prepared by adding the second metal to manganese oxides supported on titanium dioxide（TiO2）,where,A indicates Fe2O3,WO3,MoO3,and *** catalytic activity,N2 selectivity,and SO2 poisonous tolerance were *** catalytic performance at low temperatures decreased in the following order：Mn-W/TiO2〉Mn-Fe/TiO2〉Mn-Cr/TiO2〉Mn-Mo/TiO2,whereas the N2 selectivity decreased in the order：Mn-Fe/TiO2〉Mn-W/TiO2〉Mn-Mo/TiO2〉Mn-Cr/*** the presence of 0.01%SO2 and 6%H2O,the NOx conversions in the presence of Mn-W/TiO2,Mn-Fe/TiO2,or Mn-Mo/TiO2 maintain 98.5%,95.8%and 94.2%, respectively,after 8 h at 120°C at GHSV 12600 h？ 1 .As effective promoters,WO3 and Fe2O3 can increase N2 selectivity and the resistance to SO2 of MnOx/TiO2 *** Fourier transform infrared（FTIR）spectra of NH3 over WO3 show the presence of Lewis acid *** results suggest that WO3 is the best promoter of MnOx/TiO2,and Mn-W/TiO2 is one of the most active catalysts for the low temperature selective catalytic reduction of NO with NH3.

关键词： Selective catalytic reduction of NO with NH3 Low-temperature selective catalytic reduction binary metal oxide catalyst FTIR NH3-TPD

Classification-based self-adaptive differential evolution and its application in multi-lateral multi-issue negotiation

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Frontiers of Computer Science 2012年第4期6卷 442-461页

作者： xiaojun bi Jing xiao School of Information and Communication Engineering Harbin Engineering UniversityHarbin 150001China School of Information Engineering Liaoning Provincial College of CommunicationsShenyang 110122China

Multi-lateral multi-issue negotiations are the most complex realistic negotiation problems. Automated ap- proaches have proven particularly promising for complex ne- gotiations and previous research indicates evolutionary com- putation could be useful for such complex systems. To im- prove the efficiency of realistic multi-lateral multi-issue ne- gotiations and avoid the requirement of complete informa- tion about negotiators, a novel negotiation model based on art improved evolutionary algorithm p-ADE is proposed. The new model includes a new multi-agent negotiation protocol and strategy which utilize p-ADE to improve the negotia- tion efficiency by generating more acceptable solutions with stronger suitability for all the participants. Where p-ADE is improved based on the well-known differential evolution （DE）, in which a new classification-based mutation strategy DE/rand-to-best/pbest as well as a dynamic self-adaptive pa- rameter setting strategy are proposed. Experimental results confirm the superiority of p-ADE over several state-of-the-art evolutionary optimizers. In addition, the p-ADE based multi- agent negotiation model shows good performance in solving realistic multi-lateral multi-issue negotiations.

关键词： differential evolution global optimum e-commerce agent multi-lateral multi-issue negotiation

Strategic integration of 2D perovskite and chiral quantum dot hybrid heterostructures for superior CPL detection

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Science China Technological Sciences 2025年第1期 368-377页

作者： Jiahe YAN Xi ZHANG Lei LIU Hualin bi Mengke WANG Jing LI jun WANG Department of Chemistry College of SciencesNortheastern University Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Circularly polarized light（CPL） detection has garnered significant research interest due to its extensive applications in optoelectronics and quantum *** perovskites possess CPL detection capabilities due to their inherent ***,incorporating organic amine spacers distorts the crystal lattice,resulting in defects that reduce the sensitivity of CPL *** study introduces the concept of chiral superposition for the first time,reporting two mixed heterostructures composed of two-dimensional（2D） chiral perovskite（R/S-MBA）2MAPb2I7（R/S）,chiral quantum dots（R/S-MBA）-CsPbBr3（R/SQD）,and chiral carbon dots（Ch-CDs）.The addition of chiral quantum dots/Ch-CDs fills the defects of the chiral perovskite films and reduces the electron-hole recombination rate in chiral hybrid perovskites,thereby significantly enhancing the circularly polarized sensitivity of the CPL *** adjusting the concentration of chiral quantum dots,controllability of spin electron transfer is achieved,which has a notable impact on circular dichroism（CD） and anisotropy factor *** anisotropy factor glhpof the mixed heterostructure R/S-R/SQD is approximately 21.58 times higher than that of single-phase chiral perovskites,and the asymmetry factor gCDincreases ***,this work opens up a new effective pathway for achieving high-sensitivity CPL detection,with promising applications in optoelectronic technologies such as spin information communication and quantum optics.

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定向电场下W_(6)C_(6)团簇的超卤素调制及非线性光学特性

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原子与分子物理学报 2025年第3期42卷 72-76页

作者：蔡璧钧段宇静魏强重庆理工大学理学院重庆400050

本文采用密度泛函(DFT)方法研究了定向外电场(OEEF)对W_(6)C_(6)团簇几何结构、电子性质以及非线性光学响应(NLO)的影响.计算结果表明W_(6)C_(6)的结构在一定OEEF强度下可以保持稳定.OEEF可以增大W_(6)C_(6)团簇的电子亲和能(EA值),且... 详细信息

本文采用密度泛函(DFT)方法研究了定向外电场(OEEF)对W_(6)C_(6)团簇几何结构、电子性质以及非线性光学响应(NLO)的影响.计算结果表明W_(6)C_(6)的结构在一定OEEF强度下可以保持稳定.OEEF可以增大W_(6)C_(6)团簇的电子亲和能(EA值),且在特定强度下,OEEF可以将W_(6)C_(6)团簇转变为超卤素.通过对EA值的非线性拟合可以实现对W_(6)C_(6)团簇的连续调制.进一步对不同外电场下W_(6)C_(6)团簇的最高占据分子轨道(HOMO)和最低未占据分子轨道(LUMO)能级进行分析,发现OEEF降低了W_(6)C_(6)团簇LUMO能级是其EA值增大的主因.此外,OEEF可以显著增大W_(6)C_(6)团簇的平均极化率和第一超极化率,尤其是第一超极化率,改变其非线性光学性质.

关键词：定向外电场超原子密度泛函理论 NLO W_(6)C_(6)团簇

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Numerical simulations of compressible mixing layers with a discontinuous Galerkin method

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Acta Mechanica Sinica 2011年第3期27卷 318-329页

作者： xiao-Tian Shi jun Chen Wei-Tao bi Chi-Wang Shu Zhen-Su She State Key Laboratory for Turbulence and Complex Systems and Dept. Mechanical and Aerospace Engineering College of EngineeringPeking University100871 BeijingChina Division of Applied MathematicsBrown UniversityProvidence RI 02912USA Division of Applied Mathematics Brown University Providence RI 02912 USA

Discontinuous Galerkin（DG） method is known to have several advantages for flow simulations,in particular,in fiexible accuracy management and adaptability to mesh refinement. In the present work,the DG method is developed for numerical simulations of both temporally and spatially developing mixing layers. For the temporally developing mixing layer,both the instantaneous fiow field and time evolution of momentum thickness agree very well with the previous results. Shocklets are observed at higher convective Mach numbers and the vortex paring manner is changed for high compressibility. For the spatially developing mixing layer,large-scale coherent structures and self-similar behavior for mean profiles are investigated. The instantaneous fiow field for a three-dimensional compressible mixing layer is also reported,which shows the development of largescale coherent structures in the streamwise direction. All numerical results suggest that the DG method is effective in performing accurate numerical simulations for compressible shear fiows.

关键词： Compressible mixing layer - Discontinuous Galerkin method . Self-similarity . Coherent structure

Fault Feature Extraction of Diesel Engine Based on bispectrum Image Fractal Dimension

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Chinese Journal of Mechanical Engineering 2018年第2期31卷 216-226页

作者： Jian Zhang Chang-Wen Liu Feng-Rong bi xiao-Bo bi xiao Yang State Key Laboratory of Engines Tianjin University

Fault feature extraction has a positive effect on accurate diagnosis of diesel engine. Currently, studies of fault feature extraction have focused on the time domain or the frequency domain of signals. However, early fault signals are mostly weak energy signals, and time domain or frequency domain features will be overwhelmed by strong back?ground noise. In order consistent features to be extracted that accurately represent the state of the engine, bispectrum estimation is used to analyze the nonlinearity, non?Gaussianity and quadratic phase coupling(QPC) information of the engine vibration signals under different conditions. Digital image processing and fractal theory is used to extract the fractal features of the bispectrum pictures. The outcomes demonstrate that the diesel engine vibration signal bispectrum under different working conditions shows an obvious differences and the most complicated bispectrum is in the normal state. The fractal dimension of various invalid signs is novel and diverse fractal parameters were utilized to separate and characterize them. The value of the fractal dimension is consistent with the non?Gaussian intensity of the signal, so it can be used as an eigenvalue of fault diagnosis, and also be used as a non?Gaussian signal strength indicator. Consequently, a symptomatic approach in view of the hypothetical outcome is inferred and checked by the examination of vibration signals from the diesel motor. The proposed research provides the basis for on?line monitoring and diagnosis of valve train faults.

关键词： Engine fault diagnosis bispectrum image processing Fractal Signal processing

Enhancement of motor functional recovery in thoracic spinal cord injury: voluntary wheel running versus forced treadmill exercise

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Neural Regeneration Research 2025年第3期20卷 836-844页

作者： Do-Hun Lee Dan Cao Younghye Moon Chen Chen Nai-Kui Liu xiao-Ming Xu Wei Wu Spinal Cord and Brain Injury Research Group Stark Neurosciences Research InstituteIndiana University School of MedicineIndianapolisINUSA Department of Neurological Surgery Indiana University School of MedicineIndianapolisINUSA Department of Neuroscience Baylor College of MedicineHoustonTXUSA

Spinal cord injury necessitates effective rehabilitation strategies, with exercise therapies showing promise in promoting recovery. This study investigated the impact of rehabilitation exercise on functional recovery and morphological changes following thoracic contusive spinal cord injury. After a 7-day recovery period after spinal cord injury, mice were assigned to either a trained group(10 weeks of voluntary running wheel or forced treadmill exercise) or an untrained group. bi-weekly assessments revealed that the exercise-trained group, particularly the voluntary wheel exercise subgroup, displayed significantly improved locomotor recovery, more plasticity of dopaminergic and serotonin modulation compared with the untrained group. Additionally, exercise interventions led to gait pattern restoration and enhanced transcranial magnetic motor-evoked potentials. Despite consistent injury areas across groups, exercise training promoted terminal innervation of descending axons. In summary, voluntary wheel exercise shows promise for enhancing outcomes after thoracic contusive spinal cord injury, emphasizing the role of exercise modality in promoting recovery and morphological changes in spinal cord injuries. Our findings will influence future strategies for rehabilitation exercises, restoring functional movement after spinal cord injury.

关键词： behavioral assessment motor function neural plasticity running wheel exercise spinal cord injury treadmill exercise voluntary exercise

IS: Interest Set to Enhance Flow Transmission in Named-Data Networking

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China Communications 2016年第S1期13卷 65-71页

作者： JIANG xiaoke bi jun Institute for Network Sciences and Cyberspace Tsinghua University Department of Computer Science and Technology Tsinghua University Tsinghua National Laboratory for Information Science and Technology

Named-data Networking(NDN) is a promising future Internet architecture, which introduces some evolutionary elements into layer-3, e.g., consumer-driven communication, soft state on data forwarding plane and hop-byhop traffic control. And those elements ensure data holders to solely return the requested data within the lifetime of the request, instead of pushing data whenever needed and whatever it is. Despite the dispute on the advantages and their prices, this pattern requires data consumers to keep sending requests at the right moments for continuous data transmission, resulting in significant forwarding cost and sophisticated application design. In this paper, we propose Interest Set(IS) mechanism, which compresses a set of similar Interests into one request, and maintains a relative long-term data returning path with soft state and continuous feedback from upstream. In this way, IS relaxes the above requirement, and scales NDN data forwarding by reducing forwarded requests and soft states that are needed to retrieve a given set of data.

关键词： index terms—named-data networking flow transmission

Characterization of thermal-induced distorted face-centered cubic structure in pure titanium

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Journal of Iron and Steel Research International 2019年第6期26卷 653-658页

作者： Hai-chen Wu xiao-fang bi School of Materials Science and Engineering Beihang University Beijing 100191 China

After 900 ℃ high-vacuum annealing and air cooling, a special band was observed in pure titanium. Energy-dispersive spectrum showed that the composition of the band and the matrix is the same. By tilting the band to different zone axes and taking selected-area electron diffraction (SAED) patterns, we found that the structure of the band is distorted face-centered cubic (fcc) with the lattice constants a, b, and c deviating slightly from each other on the basis of the analyses of the SAED patterns together with the tilting angles. The lattice constants a, b, and c are calculated based on the measurement of interplanar spacing according to high-resolution transmission electron microscopy (HRTEM) images. The orientation relation between the hexagonal-close-packed (hcp) matrix and the distorted fcc band is [11(2)0]hcp//[110]fcc and (0001)hcp//(1(1)1)fcc according to SAED analysis. The phase boundary between the matrix and the band was observed to demonstrate serrated configuration composed of two kinds of micro-steps: ((1)11)//(0002) and ((1)11)//(10(1)1) on the basis of Cs-corrected HRTEM characterization. The distorted fcc band is deduced to be a thermal-induced metastable phase transformed from the high-temperature body-centered cubic (bcc) structure during the allotropic transformation from bcc to hcp based on orientation relation analysis.

关键词： Titanium Transmission electron microscopy Distorted fee Phase boundary Formation mechanism