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Improving the performance of all-solid-state supercapacitors by modifying ionic liquid gel electrolytes with graphene nanosheets prepared by arc-discharge

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Chinese Chemical Letters 2014年第6期25卷 859-864页

作者： Min-Jie shi sheng-Zhong Kou Bao-Shou Shen Jun-Wei Lang zhi Yang Xing-Bin Yan State Key Laboratory of Gansu Advanced Non-ferrous Metal Materials Department of Material Science and EngineeringLanzhou University of Technology Laboratory of Clean Energy Chemistry and Materials Lanzhou Institute of Chemical PhysicsChinese Academy of Science

Ionic liquid gel polymers have widely been used as the electrolytes in all-solid-state supercapacitors, but they suffer from low ionic conductivity and poor electrochemical performance. Arc discharge is a fast, low-cost and scalable method to prepare multi-layered graphene nanosheets, and as-made graphene nanosheets （denoted as ad-GNSs） with few defects, high electrical conductivity and high thermal stability should be favorable conductive additive materials. Here, a novel ionic liquid gel polymer electrolyte based on an ionic liquid （EM1MNTF2） and an copolymer （P（VDF-HFP）） was modified by the addition of ad-GNSs as an ionic conducting promoter. This modified gel electrolyte shows excellent thermal stability up to 400 ℃ and a wide electrochemical window of 3 V. An all-solid-state supercapacitor based on commercial activated carbon was fabricated using this modified ionic liquid gel polymer electrolyte, which shows obviously improved electrochemical behaviors compared with those of the corresponding all-solid-state supercapacitor using pure ionic liquid gel polymer electrolyte. Specially, smaller internal resistance, higher specific capacitance, better rate performance and cycling stability are achieved. These results indicate that the ionic liquid gel polymers modified by ad-GNSs would be promising and suitable gel electrolytes for high performance all-solid-state electrochemical devices.

关键词： Graphene Arc discharge Ionic liquid gel Electrolyte An-solid-state supercapacitor

Polyamides Containing Thiadiazole Units:Synthesis and Optical Properties

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Chinese Journal of Polymer Science 2014年第3期32卷 292-304页

作者： zhi-min Li 张刚 Dong-sheng Li 杨杰 College of Polymer Materials Science and Engineering of Sichuan University Institute of Materials Science & Technology Analytical & Testing CenterSichuan University State Key Laboratory of Polymer Materials Engineering (Sichuan University)

Highly refractive and transparent polyamides containing thiadiazole units have been developed. These polymers were prepared by a polycondensation reaction of 4,4＇-（1,3,4-thiadiazole-2,5-thio） his（methylene） dibenzoyl chloride （TDTBM-DC） and diamine which contained thioether （--S--） and sulfone units. They showed good thermal stabilities such as a relatively high glass transition temperature of 206-233℃ and a 5% weight-loss temperature （T5%） of 376-395 ℃. The optical transmittance of the polymer at 450 nm is higher than 83%. The heterocycle units and plural --S-- linkages provide the polymer with a high refractive index of 1.716-1.725 at 633 nm and a low birefringence of 0.003-0.004. Also they showed improved solubility in polar aprotic solvents and could form moderate strength films with tensile strength of 72.8-83.1 MPa and storage modulus of 1.0-1.8 GPa （at 200 ℃）.

关键词： Synthesis Optical property Soluble Heterocycle.

Blind Image Deblurring via Adaptive Optimization with Flexible Sparse St rue ture Control

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Journal of Computer Science & Technology 2019年第3期34卷 609-621页

作者： Ri-sheng Liu Cai-sheng Mao zhi-Hui Wang Hao-Jie Li International School of Information Science and Engineering Dalian University of TechnologyDalian 116620China Key Laboratory for Ubiquitous Network and Service Software of Liaoning Province Dalian 116620China

Blind image deblurring is a long-standing ill-posed inverse problem which aims to recover a latent sharp image given only a blurry *** far,existing studies have designed many effective priors *** latent image within the maximum a posteriori(MAP)framework in order to narrow down the solution *** non-convex priors are always integrated into the final deblurring model,which makes the optimization ***,due to unknown image distribution,complex kernel structure and non-uniform noises in real-world scenarios,it is indeed challenging to explicitly design a fixed prior for all *** we adopt the idea of adaptive optimization and propose the sparse structure control(SSC)for the latent image during the optimization *** this paper,we only formulate the necessary optiinization constraints in a lightweight MAP model with no *** we develop an inexact projected gradient scheme to incorporate flexible SSC in MAP *** Zp-norm based SSC in our previous work,we also train a group of denoising convolutional neural networks(CNNs)to learn the sparse image structure automatically from the training data under different noise levels,and we show that CNNs-based SSC can achieve similar results compared with Zp-norm but are more robust to *** experiments demonstrate that the proposed adaptive optimization scheme with two types of SSC achieves the state-of-the-art results on both synthetic data and real-world images.

关键词： blind image deblurring conv olutio nal neural net work(CNN) non-convex optimization sparse structure control(SSC)

Effects of ECAE processing temperature on the microstructure, mechanical properties, and corrosion behavior of pure Mg

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International Journal of Minerals,Metallurgy and Materials 2015年第6期22卷 639-647页

作者： zhi Li shi-jie Zhou Nan Huang School of Materials Science and Engineering Southwest Jiaotong University School of Pharmacology Chengdu Medical College College of Materials and Chemistry & Chemical Engineering Chengdu University of Technology

A two-step equal channel angular extrusion（ECAE） procedure was used to process pure Mg. The effects of ECAE processing temperature on the microstructure, mechanical properties, and corrosion behavior of pure Mg were studied. The results show that the average grain size of pure Mg decreases with decreasing extrusion temperature. After ECAE processing at 473 K, fine and equiaxed grains（~9 μm） are obtained. The sample processed at 473 K exhibits the excellent mechanical properties, whereas the sample processed at 633 K has the lowest corrosion rate. The improved corrosion resistance and mechanical properties of pure Mg by ECAE are ascribed to grain refinement and microstructural modification.

关键词： magnesium equal channel angular pressing microstructure corrosion resistance mechanical properties

A Novel Alkaloid from Stemona parviflora

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Chinese Chemical Letters 2003年第2期14卷 173-175页

作者： Chang Qing zhi sheng HE 等 StateKeylaboratoryofDrugResearch ShanghaiInstituteofmateriaMedicaShanghaiInstitutesforBiologicalSciencesChineseAcademyofSciencesShanghai200031 StateKeylaboratoryofDrugResearc

A novel alkaloid was isolated from the stems and leaves of Stemona parviflora Wright. Based on the spectral methods, its structure was elucidated as parvineostemonine.

关键词： Stemona parviflora perhydroazaazulene parvineostemonine.

Band structure properties of elastic waves propagating in the nanoscaled nearly periodic layered phononic crystals

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Acta Mechanica Solida Sinica 2017年第2期30卷 113-122页

作者： A-Li Chen Li-zhi Tian Yue-sheng Wang Institute of Engineering Mechanics Beijing Jiaotong Uniuersity Beijing 100044 China

The localization factor is used to describe the band structures for P wave propagating normally in the nanoscaled nearly periodic layered phononic crystals. The localization factor is calculated by the transfer matrix method based on the nonlocal elastic continuum *** kinds of nearly periodic arrangements are concerned, i.e., random disorder, quasiperiodicity and defects. The influences of randomly disordered degree of the sub-layer＇s thickness and mass density, the arrangement of quasi-periodicity and the location of defect on the band structures and cut-off frequency are analyzed in detail.

关键词： Elastic wave Nanoscale Nearly periodic Phononic crystal Band structure

DFT Studies on Hydrogen Overfall Mechanism for Catalyzed Hydroisomerization of Pentane

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Chinese Journal of Structural Chemistry 2007年第2期26卷 239-247页

作者： AI Chun-zhi SUN Ren-An WANG Chang-sheng College of Chemistry and Chemical Engineering Liaoning Normal University Dalian 116029 China Dalian Institute of Chemical Physics The Chinese Academy of Sciences Dalian 116021 China

The mechanism and related reaction paths in the hydroisomerization of n-pentane were studied by DFT calculations at the B3LYP/6-311＋＋G^＊＊ level. Two possible transition states were theoretically predicted and verified by the vibration frequency analysis as well as the calculations of intrinsic reaction coordinates （IRC）. Furthermore, the related reaction barriers were evaluated by single point energy at the MP2/6-311＋＋G^＊＊ level with zero point vibration correction of DFT method. Thus, it is concluded that the isomerization might go through two pathways.

关键词： catalyzed isomerization of n-pentane hydrogen overfall mechanism i-pentane DFT

3-D numerical simulation of curved open channel confluence flow with partially non-submerged rigid vegetation

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Journal of Hydrodynamics 2021年第5期33卷 992-1006页

作者： Zheng-rui shi Cong-fang Ai sheng Jin School of Civil and Hydraulic Engineering Dalian University of TechnologyDalian 116024China

For the study of the effects of partially non-submerged rigid vegetation on the free-surface confluence flow in a curved open channel,a numerical simulation is carried out by using the Volume of Fluid model combined with the porous media model with the software *** model is first validated by using available experimental measurement data with a good ***,the characteristics of the separation zone generated by the centrifugal forces and the confluence flow are *** to the resistance created by the vegetation,the velocities in the separation zone are more chaotic and the separation zone becomes smaller and more *** reduction of the separation zone area of the vegetated flow in the convex bank is more significant than that in the concave *** velocities in the vegetated region become much smaller and remains so in the downstream flow after the vegetation ***,the vegetation compresses and divides the circulations in the flow area,rebuilding a structure with smaller circulations in the main flow and unclear circulations in the vegetation *** addition,the bed wall shear stresses are significantly smaller in the vegetation region and the separation zone compared to the non-vegetated *** implies that the vegetation can have the effect of protecting the river bed from erosion.

关键词： Curved open channel confluence flow porous media model non-submerged rigid vegetation separation zone

Late-model Ionic Clusters of KNO_3 and Their Configurations

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Chemical Research in Chinese Universities 2005年第5期21卷 587-591页

作者： shi Lei YANG zhi LIU zhi-qiang LIU Shu-ying School of Public Health Jilin University Changchun 130021 P. R. China Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China

Late-model ionic clusters of KNO3 were formed under the conditions of electrospray ionization. A series of peaks of the ionic clusters could be observed in the electrospray ionization mass spectra（ESIMS）. The general formulae of the ionic clusters were deduced to be K^ ＋（ KNO3 ） m and NO3^-（ KNO3 ）m. By referring to the crystal structure of KNOs , the possible configurations of these new typical ionic clusters were speculated based on the calculated data by means of the Gaussian-94^x computer program.

关键词： Cluster KNO3 Configuration Gaussian-94^* computer program