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Optimization-based particle filter for state and parameter estimation

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Journal of Systems Engineering and Electronics 2009年第3期20卷 479-484页

作者： li Fu Qi Fei Shi guangming Zhang li School of Electronic Engineering Xidian Univ. Xi'an 710071 P. R. China

In recent years, the theory of particle filter has been developed and widely used for state and parameter estimation in nonlinear/non-Gaussian systems. Choosing good importance density is a critical issue in particle filter design. In order to improve the approximation of posterior distribution, this paper provides an optimization-based algorithm （the steepest descent method） to generate the proposal distribution and then sample particles from the distribution. This algorithm is applied in 1-D case, and the simulation results show that the proposed particle filter performs better than the extended Kalman filter （EKF）, the standard particle filter （PF）, the extended Kalman particle filter （PF-EKF） and the unscented particle filter （UPF） both in efficiency and in estimation precision.

关键词： importance density particle filter extend Kalman filter

Bandwidth adaption for kernel particle filter

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Journal of Systems Engineering and Electronics 2011年第2期22卷 340-346页

作者： Fu li guangming Shi Fei Qi li Zhang School of Electronic Engineering Xidian University Xi'an 710071 P. R. China

A novel particle filter bandwidth adaption for kernel particle filter （BAKPF） is proposed. Selection of the kernel bandwidth is a critical issue in kernel density estimation （KDE）. The plug-in method is adopted to get the global fixed bandwidth by optimizing the asymptotic mean integrated squared error （AMISE） firstly. Then, particle-driven bandwidth selection is invoked in the KDE. To get a more effective allocation of the particles, the KDE with adap- tive bandwidth in the BAKPF is used to approximate the posterior probability density function （PDF） by moving particles toward the posterior. A closed-form expression of the true distribution is given. The simulation results show that the proposed BAKPF performs better than the standard particle filter （PF）, unscented particle filter （UPF） and the kernel particle filter （KPF） both in efficiency and estimation precision.

关键词： kernel density estimation adaptive bandwidth kernel,particle filter.

Different Heterogeneous Fenton Reaction Based on Foam Carrier Loaded with Photocatalysts

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Journal of Wuhan University of Technology(Materials Science) 2018年第1期33卷 85-90页

作者：邱珊 li guangming DENG Fengxia MA Fang State Key Laboratory of Urban Water Resources Center School of Environment Harbin Institute of Technology Harbin 150090 China

The effect of heterogeneous Fenton reaction was studied on methylene blue（MB） and Nitrosomonas europaea（N. europaea） cells. Four Fenton systems were prepared and compared with each other, including Nickel Foam（NF）/TiO2, NF/Bi2WO6, Ceramic foam（CM）/TiO2, and CM/Bi2WO6. The order of effect of fenton reaction ranked as NF/TiO2〉CM/TiO2〉NF/Bi2WO6〉CM/Bi2WO6. In acid or alkaline solution, the removal efficiency also decreased compared with neutral solution. With lower p H values, the nanoparticles were easier to break off from NF skeleton. Thus the synergetic effect of photocatalysis and fenton reaction can not take action. As for CM skeleton, the bond –Si-O-can bind with TiO2 or Bi2WO6. The membrane fluidity was used as an indicating parameter. After being treated by Fenton reaction, N. europaea surface was rougher than the native bacterium and the bulges on cell surface became irregular, which is attributed to change of lipopolysaccharide patches. Polarization of N. europaea cell membrane in acid medium increased more obvious than alkaline medium.

关键词： fenton reaction N europaea polarization degradation membrane

β-C(sp^(3))−H chlorination of amide derivatives via photoinduced copper charge transfer catalysis

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Chinese Chemical Letters 2024年第2期35卷 361-365页

作者： Yuhang He Chao Tian Guanghui An guangming li Key Laboratory of Functional Inorganic Material Chemistry (MOE) School of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150080China

An atom economicβ-C(sp^(3))−H chlorination of amide derivatives has been *** mild protocol employs CuCl_(2) instead of palladium catalysts with atom-economic HCl as chlorine sources and enables the late-stage functionalization of medicine *** studies suggest a plausible visible light triggered ligand-to-metal charge transfer(LMCT)/1,4-hydrogen atom transfer(HAT)cascade.

关键词： Photoinduced copper catalysis ligand-to-metal charge transfer 1,4-Hydrogen atom transfer β-Halogenated amide Late-stage functionalization

Characteristics and evolution of ore-forming fluids of the Chongjiang copper deposit in the Gangdise porphyry copper belt, Tibet

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Journal of University of Science and Technology Beijing 2007年第2期14卷 97-102页

作者： Yuling Xie Jiuhua Xu guangming li Zhiming Yang Longsheng Yi Civil and Environmental Engineering School University of Science and Technology Beijing Beijing 100083 China Chengdu Institute of Geology and Mineral Resource Ministry of Land and Resource Chengdu 610082 China Institute of Mineral Resources China Academy of Geological Science Beijing 100037 China

Petrography, microthermometry, and scanning electron microscope/energy dispersive spectrometer （SEM/EDS） studies were performed on the fluid inclusions in the ore-beating quartz veins and quartz phenocrysts in the porphyry of the Chongjiang porphyry copper deposit. The analyses of the fluid inclusions indicate that the ore-forming fluids were exsolved from magma. They are near-saturated, supercritical, rich in volatile constituents, and have the capture temperature of 362-389℃ and salinities of 17.7wt%- 18.9wt% NaC1 eq. With the decreasing of temperature and pressure, the supercritical fluids were separated into a low salinity vapor phase and a high salinity liquid phase. During quartz-sericitization, the high salinity fluid boiled and separated into a low salinity vapor phase and a high salinity liquid phase. The high salinity inclusions that formed in the boiling process had daughter mineral melting temperatures higher than the homogenization temperatures of the vapor and liquid phases. The late fluids that are responsible for argillization are of lower temperature and salinity.

关键词： Gangdise porphyry copper belt Chongjiang copper deposit fluid inclusions ore-forming fluids

Pd(I)-catalyzed ring-opening arylation of cyclopropyl-α-aminoamides:Access toα-ketoamide peptidomimetics

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Chinese Chemical Letters 2024年第6期35卷 320-326页

作者： Yue Sun liming Yang Yaohang Cheng Guanghui An guangming li School of Chemistry and Materials Science Heilongjiang UniversityHarbin 150080China

We report the unprecedent Pd(I)catalyzed ring-opening arylation of cyclopropyl-α-*** protocol allows facile access to biologically important α-ketoamide-containing oligopeptides and even more challenging peptide-natural product *** selectivity was achieved by introduction of special unnatural amino acids,which also meets the requisite of bioorthogonal *** investigations reveals a distinct domino radical ring-opening process through Pd(I)catalysis.

关键词： Pd(I)catalysis Ring-opening arylation Domino reactions Oligopeptides Late-stage functionalization

Upgrading pyrolytic carbon-blacks (CBp) from end-of-life tires: Characteristics and modification methodologies

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Frontiers of Environmental Science & Engineering 2020年第2期14卷 9-25页

作者： Jiaxue Yu Junqing Xu Zhenchen li Wenzhi He Juwen Huang Junshi Xu guangming li State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China Shanghai Tire Craftsman Technology Co. Ltd.Shanghai 201400China

Over 1 billion end-of-life tires(ELTs)are generating annually,and 4 billion ELTs are currently abandoned in landfills and stockpiles worldwide,according to the statistics,leading to the environmental and health *** circumvent these issues,pyrolysis,as an attractive thermochemical process,has been addressed to tackle the ELTs'problem to reduce the risks as well as increase the material ***,due to the lack of systematic characteristic analysis and modification methods,poor quality of CBp limits the improvement of ELTs pyrolysis in industry applications,which plays a crucial role in the economic feasibility of pyrolysis *** this review,we have summarized the state-of-the-art characteristics and modification methodologies of the upgrading of CBp,to in-depth understand the surface microstructures and physiochemical properties o f CBp for the foundation for modification *** virtue of the proper selection of modification methods and modifying agents,the new generation of multifunctional carbon materials with desired properties can be instead of the traditional materials of CB,promising broader and various application fields.

关键词： Pyrolysis carbon-blacks CBp Post-pyrolysis Demineralization Surface modification

Preparing graphene from anode graphite of spent lithium-ion batteries

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Frontiers of Environmental Science & Engineering 2017年第5期11卷 77-84页

作者： Wenxuan Zhang Zhanpeng liu Jing Xia Feng li Wenzhi He guangming li Juwen Huang State Key Laboratory of Pollution Control and Resource Reuse School of Environmental Science and Engineering Tongji University Shanghai 200092 China

With extensive use of lithium ion batteries （liBs）, amounts of liBs were discarded, giving rise to growth of resources demand and environmental risk. In view of wide usage of natural graphite and the high content （12%-21%） of anode graphite in spent liBs, recycling anode graphite from spent liBs cannot only alleviate the shortage of natural graphite, but also promote the sustainable development of related industries. After calcined at 600°Cfor 1 h to remove organic substances, anode graphite was used to prepare graphene by oxidation-reduction method. Effect of pH and N2H4·H2O amount on reduction of graphite oxide were probed. Structure of graphite, graphite oxide and graphene were characterized by XRD, Raman and FTIR. Graphite oxide could be completely reduced to graphene at pH 11 and 0.25 mL N2H4·H2O. Due to the presence of some oxygen-containing groups and structure defects in anode graphite, concentrated H2SO4 and KMnO4 consumptions were 40% and around 28.6% less than graphene preparation from natural graphite, respectively.

关键词： Spent liBs Graphite Graphite oxide Graphene

Visible-light-enabled ruthenium-catalyzed para-C-H difluoroalkylation of anilides

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Chinese Chemical Letters 2023年第3期34卷 293-297页

作者： Yaohang Cheng Xian Zhang Guanghui An guangming li Zhenyu Yang Key Laboratory of Functional Inorganic Material Chemistry(MOE) School of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150080China School of Pharmaceutical and Materials Engineering Taizhou UniversityTaizhou 318000China

Visible-light-mediated para-C-H difluoroalkylation of anilides via combination of steric effects and Lewis acid activation strategies has been developed. The addition of(C_6H_5O)_(2)P(O)OH and Ag_(2)CO_(3) properly tune the redox potential of ruthenium catalyst and leads to mild reaction conditions. The protocol exhibits broad functional group tolerance and allows the late-stage functionalization of complex bioactive molecules.

关键词： C-H activation para-Selectivity Photocatalysis Difluoroalkylation Late-stage functionalization