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Effects on the thermal expansion coefficient and dielectric properties of CLST/PTFE filled with modified glass fiber as microwave material

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Chinese Chemical Letters 2019年第5期30卷 1111-1114页

作者： Liu Zheng Jing Zhou Jie Shen yanyuan qi Wen Chen State Key Laboratory of Advanced Technology for Materials Synthesis and Processing School of Materials Science and Engineering Wuhan University of Technology

Ceramic and polytetrafluoroethylene composites as dielectric materials have a low dielectric loss at high frequency and play an important role in the modern communication ***,room temperature phase transformation of PTFE resins,which is accompanied by a large volume change(>400 ppm/℃),seriously affects the dimensional stability and performance stability of *** LD125 modified glass fiber(GF)was introduced to the CaO-Li2 O-Sm2O3-TiO2(CLST)/PTFE composite,to reduce the thermal expansion coefficient(CTE)of the *** tri-phase composites(CLST/PTFE/GF)show the low dielectric loss and excellent *** effect of GF content on the dielectric properties and CTE was also *** CLST/PTFE filled with 5%GF exhibits the best overall performance,which is a promising microwave dielectric material for microwave communication.

关键词： Microwave communication Thermal expansion coefficient CLST PTFE Dielectric loss Dielectric constant

Energy-dispersive X-ray Spectroscopy for the Quantitative Analysis of Pyrite Thin Specimens

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Journal of Wuhan University of Technology(Materials Science) 2023年第6期38卷 1304-1310页

作者： LUO Tingting GUO Yi DENG Zhao LIU Xiaoqing SUN Zhenya qi yanyuan YANG Meijun Center for Materials Research and Analysis Testing Wuhan University of Technology Wuhan 430070China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070Wuhan

To explore ways to improve the accuracy of quantitative analysis of samples in the micrometer to nanometer range of magnitudes,we adopted analytical transmission electron microscopy(AEM/EDS)for qualitative and quantitative analysis of pyrite ***,the k factor of pyrite is calculated *** develop an appropriate non-standard quantitative analysis model for pyrite materials,the experimentally calculated k factor is compared with that estimated from the non-standard quantitative analytical model of the instrument *** experimental findings demonstrate that the EDS attached to a TEM can be employed for precise quantitative analysis of micro-and nanoscale regions of pyrite ***,it serves as a reference for improving the results of the EDS quantitative analysis of other sulfides.

关键词： analytical transmission electron microscopy(AEM) energy dispersive X-ray spectroscopy(EDS) pyrite thin specimen quantitative analysis

Low-coordination water Prussian white as cathode for high-performance potassium-ion batteries

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Chinese Chemical Letters 2021年第8期32卷 2433-2437页

作者： Yang Xia Wei Jin yanyuan qi Hang Li Zelang Jian Wen Chen State Key Laboratory of Advanced Technology for Materials Synthesis and Processing School of Materials Science and EngineeringWuhan University of TechnologyWuhan 430070China

Prussian whites(PWs) with a three-dimensional framework can accommodate the insertion and extraction of ions with large radius,which have been widely used in potassium ion ***,PWs show the poor cycling performance and inferior rate ability because of high coordinated *** this work,PWs with different water content were synthesized via a coprecipitation method by controlling the reaction *** sample with low-coordination water prohibits the best electrochemical *** shows a high capacity of 120.5 mAh/g at 100 mA/g for potassium-ion batteries(KIBs).It also exhibits a good rate performance,displaying a capacity of 73.2 mAh/g at 500 mA/g.

关键词： Prussian white Potassium ion batteries Low-coordinated water Cathode Reaction temperature

Polymer “Tape”-Assisted Ball-Milling Method Fabrication Few-Atomic-Layered Bismuth for Improving K^(+)/Na^(+)Storage

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Energy & Environmental Materials 2021年第3期4卷 421-427页

作者： Yu Tian Hang Li Shuyan Zhang Haode Zhang Guangze Li Dongqing Liu yanyuan qi Zelang Jian Xingke Cai Fujun Li Wen Chen School of Materials Science and Engineering Key Laboratory of Advanced Technology for Materials Synthesis and ProcessingWuhan University of TechnologyWuhan 430070China Institute for Advanced Study Shenzhen UniversityShenzhen 518060China College of Mechatronics and Control Engineering Shenzhen UniversityShenzhen 518060China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) College of ChemistryNankai UniversityTianjing 300071China

Few-layered 2D analogs exhibit new physical/chemical properties,leading to a strong research interest and broad areas of ***,lots of methods(such as ultrasonic and electrochemical methods)have already used to prepared 2D ***,these methods suffer from the drawbacks of low yield,high cost,or precarious state,which limit the largescale *** by the famous Scotch tape method,we develop a ball-milling with polymer"tape"method,fabricating few-atomic-layered material,showing the high-yield,low-cost,and much *** electrode material,ultrathin 2D materials can shorten the ion transfer pathway,contributing to the development of high-power ***,fewatomic-layered structure can expose more active sites to increase their capacity,showing special energy storage *** use the as-prepared few-atomic-layered Bi(FALB)and reduced oxide graphene composites as the anode for potassium/sodium-ion batteries(KIBs/NIBs).The sample achieves a high reversible capacity of 395 m Ah g^(-1)for KIBs,of which FALB contributes 438 m Ah g^(-1)(higher than the theoretical capacity of Bi,386 m Ah g^(-1)),and it carries outstanding cycle and rate performance in KIBs/NIBs.

关键词： energy storage mechanism few-atomic-layered material polymer"tape" potassium/sodium-ion batteries reduced graphene oxide

In Situ Growth of Vanadium Oxide on Reduced Graphene Oxide for the Low-Temperature NO-SCR by NH3

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Journal of Wuhan University of Technology(Materials Science) 2019年第3期34卷 572-578页

作者： LI Meiyan JIN Wei State Key Laboratory of Silicate Materials for Architectures School of Materials Science and EngineeringWuhan University of TechnologyWuhan430070China Center for Material Research and Analysis Wuhan University of TechnologyWuhan430070China

The vanadium oxide/reduced graphene oxide（V2 O5/rGO） composite catalyst which determined the selective catalytic reduction activity（SCR） of NO with NH3 was prepared by a simple solvothermal method. The physicochemical properties of the catalysts were characterized by X-ray diffraction（XRD）, scanning electron microscopy（SEM）, Raman, X-ray energy spectrometer（XPS） and N2 sorption isotherm measurement（BET）. Results of NH3-SCR showed that the NO conversion of V2 O5/rGO catalyst could reach 54.3% at 100 ℃. And the removal of NO increased to 74.6% when the temperature was up to 220 ℃. By characterizing the microstructure and morphology of the V2 O5/rGO catalysts prepared by in-situ growth and mechanical mixing methods, it was further shown that V2 O5 nanoparticles were highly dispersed and in situ growth on the rGO surface. Based on X-ray energy spectrometer, V2 O5/r GO catalyst had good low temperature denitrification performance due to the chemical adsorption oxygen and low-valent vanadium oxide contained in V2 O5/rGO catalyst, which was beneficial to the redox reaction between V2 O5 and graphene.

关键词： V2O5/rGO catalyst NH3-SCR graphene in situ growth

Boosting Li-ion storage in Li2MnO_(3) by unequal-valent Ti4+-substitution and interlayer Li vacancies building

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Chinese Chemical Letters 2023年第4期34卷 564-569页

作者： Yu Tian Yuling Zhao Fanqi Meng Kaicheng Zhang yanyuan qi Yujie Zeng Congcong Cai Yuli Xiong Zelang Jian Yang Sun Lin Gu Wen Chena School of Materials Science and Engineering Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China School of Materials Shenzhen Campus of Sun Yat-sen UniversityShenzhen 518107China C Innovation Laboratory Contemporary Amperex Technology Ltd.(CATL)Ningde 352100China Institute of Physics Chinese Academy of SciencesBeijing 100190China Sanya Science and Education Innovation Park of Wuhan University of Technology Wuhan 430070China

Lithium rich layered oxide(LRLO) has been considered as one of the promising cathodes for lithium-ion batteries(LIBs). The high voltage and large capacity of LRLO depend on Li2MnO_(3)phase. To ameliorate the electrochemical performance of Li2MnO_(3), also written as Li(Li1/3Mn2/3)O_(2), we propose a strategy to substitute Mn4+and Li+in Mn/Li transition metal layer with Ti4+, which can stabilize the structure of Li2MnO_(3)by inhibiting the excessive oxidation of O_(2)-above 4.5 V. More significantly, the unequal-valent substitution brings about the emergence of interlayer Li vacancies, which can promote the Li-ion diffusion based on the enlarged interlayer and increase the capacity by activating the Mn3+/4+redox. We designed Li0.7[Li1/3Mn2/3]0.7Ti0.3O_(2)with high interlayer Li vacancies, which presents a high capacity(290 m Ah/g at 10 m A/g) and stable cycling performance(84% over 60 cycles at 50 m A/g). We predict that this strategy will be helpful to further improve the electrochemical performance of LRLOs.

关键词： Lithium-ion batteries Li2MnO_(3) Unequal-valent Ti4+-substitution Interlayer Li vacancies Activated Mn3+/4+redox

The temporal-spatial expression and functional analysis of three gustatory receptor genes in Solenopsis invicta using sweet and bitter compounds

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Insect Science 2024年第2期31卷 448-468页

作者： Muhammad Irfan Waris yanyuan Lei Guojun qi Ziying Guan Abdul Rashied Jie Chen Lihua Lyu Institute of Plant Protection Guangdong Academy of Agricultural SciencesGuangdong Provincial Key Laboratory of High Technology for Plant ProtectionGuangzhouChina Department of Entomology College of Plant ProtectionSouth China Agricultural UniversityGuangzhouChina

The insect gustatory system participates in identifying potential food sources and avoiding toxic *** this process,gustatory receptors(GRs)recognize feeding stimulant and deterrent ***,the GRs involved in recognizing stimulant and deterrent compounds in the red imported fire ant,Solenopsis invicta,remain ***,we conducted a study on the genes SinvGR1,SinvGR32b,and SinvGR28a to investigate the roles of GRs in detecting feeding stimulant and deterrent *** this current study,we found that sucrose and fructose are feeding stimulants and the bitter compound quinine is a feeding *** fire ant workers showed significant behavior changes to avoid the bitter taste in feeding stimulant *** transcription quantitative real-time polymerase chain reaction results from developmental stages showed that the SinvGR1,SinvGR32b,and SinvGR28a genes were highly expressed in fire ant ***-specific expression profiles indicated that SinvGR1,SinvGR32b,and SinvGR28a were specifically expressed in the antennae and foreleg tarsi of workers,whereas SinvGR32b gene transcripts were also highly accumulated in the male ***,the silencing of SinvGRI or SinvGR32b alone and the co-silencing of both genes disrupted worker stimulation and feeding on sucrose and *** results also showed that SinvGR28a is required for avoiding quinine,as workers with knockdown of the SinvGR28a gene failed to avoid and fed on *** study first identified stimulant and deterrent compounds of fire ant workers and then the GRs involved in the taste recognition of these *** study could provide potential target gustatory genes for the control of the fire ant.

关键词： behavioral responses feeding assays gustatory receptors RNA interference Solenopsis invicta temporal-spatial expression

钽镁酸钡缓冲层对锆钛酸铅铁电薄膜性能的影响

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硅酸盐学报 2015年第11期43卷 1555-1560页

作者：梁雄毅吴智秦霞周静祁琰媛武汉理工大学材料科学与工程学院武汉430070

采用溶胶–凝胶工艺在Pt/Ti/Si O2/Si基片上,通过引入钽镁酸钡[Ba(Mg1/3Ta2/3)O3,BMT]缓冲层,制备了锆钛酸铅[Pb(Zr0.52Ti0.48)O3,PZT]铁电薄膜。研究了BMT缓冲层对PZT铁电薄膜结晶和性能的影响。结果表明:引入BMT缓冲层利于PZT薄膜的生... 详细信息

采用溶胶–凝胶工艺在Pt/Ti/Si O2/Si基片上,通过引入钽镁酸钡[Ba(Mg1/3Ta2/3)O3,BMT]缓冲层,制备了锆钛酸铅[Pb(Zr0.52Ti0.48)O3,PZT]铁电薄膜。研究了BMT缓冲层对PZT铁电薄膜结晶和性能的影响。结果表明:引入BMT缓冲层利于PZT薄膜的生长;PZT薄膜具有钙钛矿结构,且没有裂纹、结晶良好、致密性好;缓冲层的厚度对PZT铁电薄膜的微观结构和铁电性能有重要影响。随BMT缓冲层厚度增加,PZT晶粒增大,介电损耗tanδ逐渐减少,介电常数εr和剩余极化强度Pr先增大后减少,矫顽场Ec先减少后增大。当BMT缓冲层厚约为10 nm时,PZT薄膜具有最优的铁电性能:εr=1 850,Pr=20.2μC/cm2,Ec=43.9 k V/mm。这与BMT与PZT具有相似的晶格常数、较小的晶格失配度和相近的禁带宽度有关。

关键词：锆钛酸铅薄膜钽镁酸钡缓冲层溶胶–凝胶法铁电性能

Friction between Strongly Compressed Polymer Brushes

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Chinese Journal of Polymer Science 2024年第9期42卷 1368-1374,I0008页

作者： qi Liao Institute of Chemistry Chinese Academy of SciencesBejing 100190China

We present the results of molecular dynamics simulations of steady shear between a pair of neutral polymer brushes,as well as a pair of charged polymer brushes in the strongly compressed *** results of the molecular dynamic simulations of neutral and polyelectrolyte brushes in implicit solvent including normal forces,shear forces,viscosities and friction coefficients as a function of separation between brushes,are presented in the *** comparison of the simulation results of neutral and charged brushes shows that the charged brushes is in the quasi-neutral regime,and the dependence of viscosity on the separation distance show the similar power law of neutral *** simulation results confirm that the implicit solvent simulations of polyelectrolyte brushes that ignore hydrodynamics interaction are in agreement with the scaling predictions qualitatively because of screening of hydrodynamic interaction and long-range electrostatic interactions on the correlation length *** of neutral and charged brushes show the lubrication properties that the friction coefficient decreases with the separation decreases at enough large ***,a maximum of friction coefficients is observed for polyelectrolyte brushes,which is in contrast to the neutral brushes with monotonical dependence.

关键词： Polymer brush Frictions coefficient Polyelectrolyte Lubrication