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Ionic liquids for electrochemical energy storage devices applications

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Journal of Materials Science & Technology 2019年第4期35卷 674-686页

作者： huan liu Haijun Yu College of Materials Science & Engineering Key Laboratory of Advanced Functional MaterialsMinistry of EducationBeijing University of Technology

Ionic liquids, defined here as room-temperature molten salts, composed mainly of organic cations and(in)organic anions ions that may undergo almost unlimited structural variations with melting points below 100?C. They offer a unique series of physical and chemical properties that make them extreme important candidates for several energy applications, especially for clean and sustainable energy storage and conversion materials and devices. Ionic liquids exhibit high thermal and electrochemical stability coupled with low volatility, create the possibility of designing appropriate electrolytes for different type batteries and supercapacitors. Herein, varieties of ionic liquids applications are reviewed on their utilization as electrolytes for Li-ion batteries, Na-ion batteries, Li-O_2(air) batteries, Li-Sulfur(Li-S) batteries, supercapacitors and as precursors to prepare and modify the electrode materials, meanwhile,some important research results in recent years are specially introduced, and the perspective on novel application of ionic liquids is also discussed.

关键词： Ionic liquids Batteries Supercapacito Electrolyte Electrode

Rh2O3/hexagonal CePO4 nanocatalysts for N2O decomposition

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Frontiers of Chemical Science and Engineering 2017年第4期11卷 586-593页

作者： liu, huan Ma, Zhen Fudan Univ Dept Environm Sci & Engn Shanghai Key Lab Atmospher Particle Pollut & Prev Shanghai 200433 Peoples R China

Hexagonal CePO4 nanorods were prepared by a precipitation method and hexagonal CePO4 nanowires were prepared by hydrothermal synthesis at 150 ℃. Rh （NO3）3 was then used as a precursor for the impregnation of Rh203 onto these CePO4 materials. The Rh203 supported on the CePO4 nanowires was much more active for the catalytic decomposition of N20 than the RhzO3 supported on CePO4 nanorods. The stability of both catalysts as a function of time on stream was studied and the influence of the co-feed （CO2, O2, H20 or O2/H20） on the N20 decomposition was also investigated. The samples were characterized by N2 adsorption-desorption, induc- tively coupled plasma optical emission spectroscopy, X- ray diffraction, transmission electron microscopy, X-ray photoelectron microscopy, hydrogen temperature-pro- grammed reduction, oxygen temperature-programmed desorption, and CO2 temperature-programmed desorption in order to correlate the physicochemical and catalytic properties.

关键词： Rh2O3 CePO4 N2O decomposition

Rh_2O_3/monoclinic CePO_4 composite catalysts for N_2O decomposition and CO oxidation

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Chinese Journal of Chemical Engineering 2018年第1期26卷 109-115页

作者： huan liu Zhen Ma Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention Department of Environmental Science and EngineeringFudan University

CePO4 （in particular, monoclinic CePO4） has been rarely used to make supported catalysts. Herein, monoclinic CeP04 nanoparticles were prepared by calcining hexagonal CePO4 nanomds （prepared by precipitation） in air at 900 ℃. Monoclinic CePO4 nanowires were prepared by calcining hexagonal CePO4 nanowires （prepared by hydrothermal synthesis at 150 ℃） in air at 900 ℃. Both monoclinic CePO4 materials were used to support Rh2O3 by impregnation using Rh（NO3）3 as a precursor （followed by calcination）. The catalytic performance of Rh2O3/monoclinic CePO4 composite materials in N2O decomposition and CO oxidation was investigated. It was found that Rh2O3 supported on monoclinic CePO4 nanowims was much more active than Rh2O3 supported on monoclinic CePO4 nanoparticles. The stability of catalysts as a function of reaction time on stream was studied in both reactions. The influence of co-fed CO2, O2, and H2O on the catalytic activity in N20 decomposition was also studied. These catalysts were characterized by employing N2 adsorption-desorption, ICP-OES, XRD, TEM, XPS, H2-TPR, O2-TPD, and CO2-TPD. The correlation between physicochemical properties and catalytic properties was discussed.

关键词： Rh2O3 CePO4 N2O decomposition CO oxidation Catalyst

High-pressure structures of InBi predicted by particle swarm optimization algorithm

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Chinese Physics B 2012年第2期21卷 393-397页

作者： liu huan-huan liu Yan-Hui Department of Physics College of ScienceYanbian UniversityYanji 133002China

We extensively explore the high-pressure structures of InBi by using a newly developed particle swarm optimization algorithm. An orthorhombic Imma structure is discovered to be stable from 43.7 GPa to 107.9 GPa, ruling out the previously speculated cubic structure. Further increasing the pressure, we find a tetragonal P4/nmm structure which is energetically more favourable from 107.9 CPa to 200 GPa. Especially, the tetragonal P4/nmm structure is known to occur at high pressure in the structures of ZnO and MgTe. We also predict this structure to be a high-pressure structure of ZnTe. Thus the tetragonal P4/nmm structure may be a universal high-pressure structure of the Ⅱ-Ⅵ and the Ⅲ-Ⅴ compounds.

关键词： InBi structure prediction phase transitions

High Accurate Interpolation of NURBS Tool Path for CNC Machine Tools

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Chinese Journal of Mechanical Engineering 2016年第5期29卷 911-920页

作者： liu Qiang liu huan YUAN Songmei School of Mechanical Engineering and Automation Beihang University

Feedrate fluctuation caused by approximation errors of interpolation methods has great effects on machining quality in NURBS interpolation, but few methods can efficiently eliminate or reduce it to a satisfying level without sacrificing the computing efficiency at present. In order to solve this problem, a high accurate interpolation method for NURBS tool path is proposed. The proposed method can efficiently reduce the feedrate fluctuation by forming a quartic equation with respect to the curve parameter increment, which can be efficiently solved by analytic methods in real-time. Theoretically, the proposed method can totally eliminate the feedrate fluctuation for any 2nd degree NURBS curves and can interpolate 3rd degree NURBS curves with minimal feedrate fluctuation. Moreover, a smooth feedrate planning algorithm is also proposed to generate smooth tool motion with considering multiple constraints and scheduling errors by an efficient planning strategy. Experiments are conducted to verify the feasibility and applicability of the proposed method. This research presents a novel NURBS interpolation method with not only high accuracy but also satisfying computing efficiency.

关键词： NURBS interpolation feedrate machine tool CNC

PM2.5 concentration estimation using convolutional neural network and gradient boosting machine

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Journal of Environmental Sciences 2020年第12期32卷 85-93页

作者： Zhenyu Luo Feifan huang huan liu State Key Joint Laboratory of ESPC School of the EnvironmentTsinghua UniversityBeijing 100084China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing 100084China

Surface monitoring, vertical atmospheric column observation, and simulation using chemical transportation models are three dominant approaches for perception of fine particles with diameters less than 2.5 micrometers(PM2.5) concentration. Here we explored an imagebased methodology with a deep learning approach and machine learning approach to extend the ability on PM2.5 perception. Using 6976 images combined with daily weather conditions and hourly time data in Shanghai(2016), trained by hourly surface monitoring concentrations, an end-to-end model consisting of convolutional neural network and gradient boosting machine(GBM) was constructed. The mean absolute error, the root-mean-square error and the R-squared for PM2.5 concentration estimation using our proposed method is 3.56, 10.02, and 0.85 respectively. The transferability analysis showed that networks trained in Shanghai, fine-tuned with only 10% of images in other locations, achieved performances similar to ones from trained on data from target locations themselves. The sensitivity of different regions in the image to PM2.5 concentration was also quantified through the analysis of feature importance in GBM. All the required inputs in this study are commonly available, which greatly improved the accessibility of PM2.5 concentration for placed and period with no surface observation. And this study makes an exploratory attempt on pollution monitoring using graph theory and deep learning approach.

关键词： Deep learning Convolutional neural network Hybrid model PM2.5concentration

“To live a meaningful life,be yourself and make yourself”:Haoyan Jen—a pioneer of China’s environmental microbiology

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Protein & Cell 2021年第2期12卷 81-83页

作者： Xin Zhang huan liu Institute of Biophysics Chinese Academy of SciencesBeijing100101China Wuhan Institute of Virology Chinese Academy of SciencesWuhan430071China Chinese Center for Disease Control and Prevention Beijing102206China State Key Laboratory of Virology Wuhan430072China

There is a man who improves our living and working environment by turning pesticide residues in the field into nutrients for the crops,turning such wastes as paper and sawdust into sugar,which is then converted into liquid alcohol fuel,or purifying malodorous and toxic industrial wastewater into clean and non-toxic *** is *** Jen(简浩然),a pioneer of China’s environmental microbiology.

关键词： wastewater yourself turning

Remote Sensing Image Registration Based on Improved KAZE and BRIEF Descriptor

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International Journal of Automation and computing 2020年第4期17卷 588-598页

作者： huan liu Gen-Fu Xiao College of Electronic and Information Engineering Jinggangshan University&Jiangxi Engineering Laboratory of Internet of Things(IoT)Technologies for Crop GrowthJi'an 343009China College of Mechanical and Electronic Jinggangshan UniversityJi'an 343009China

Remote sensing image registration is still a challenging task owing to the significant influence of nonlinear differences between remote sensing *** solve this problem,this paper proposes a novel approach with regard to feature-based remote sensing image *** are two key contributions:1)we bring forward an improved strategy of composite nonlinear diffusion filtering according to the scale factors in multi-scale space and 2)we design a gradually decreasing resolution of multi-scale pyramid *** a binary code string is served as feature descriptors to improve matching *** experiments of different categories of remote image datasets on feature extraction and feature registration are *** experimental results demonstrate the superiority of our proposed scheme compared with other classical algorithms in terms of correct matching ratio,accuracy and computation efficiency.

关键词： Remote sensing image image registration composite nonlinear diffusion filter binary code string multi-scale pyramid space

Investigations on the Interactions between Li-TFSI and Glass Fibers in the Ternary PP/GF/Li-TFSI Composites

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Chinese Journal of Polymer Science 2018年第1期36卷 113-118页

作者： Sen-Lin Gu huan-huan liu huan Cao Claude Mercier Yong-Jin Li College of Material Chemistry and Chemical EngineeringHangzhou Normal UniversityHangzhou 310036China Solvay Co.Ltd shanghai 201100China

The polypropylene/glass fiber（PP/GF） composites with excellent antistatic performance and improved mechanical properties have been reported by incorporation of a very small amount of the organic salt, lithium bis（trifluoromethanesulfonyl）imide（Li-TFSI）, into the PP/GF composites. It was considered that GF could play the role as the pathways for the movements of ions in the ternary composites. In this work, the interactions between Li-TFSI and glass fiber and the effects of such interactions on the physical properties of the composites have been systematically investigated. Three types of glass fibers with different ―OH group concentrations have been prepared in order to compare the interactions between GF and Li-TFSI. It was found that the ―OH group concentrations on the surface of glass fiber have significant effects on interactions between glass fibers and Li-TFSI. Such interactions are crucial for both the antistatic and mechanical performances of the final PP/GF/Li-TFSI composites. The investigation indicated that the GF with high ―OH group concentrations confined the movement of TFSI-, which decreased the antistatic properties of PP/GF/Li-TFSI composites. On the other hand, the GF with low ―OH group concentrations inhibited the absorption of Li-TFSI onto the GF, which also hindered the formation of Li-TFSI conductive pathway. The best antistatic performance of the ternary composites can be achieved at the intermediate ―OH concentrations on the GF.

关键词： Polypropylene Glass fiber Li-TFSI Antistatic performance