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ELECTROSTATIC INTERACTION HYBRIDS FROM WATER-BORNE CONDUCTIVE POLYANIliNE AND INORGANIC PRECURSOR CONTAINING CARBOXYL GROUP

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Chinese Journal of Polymer Science 2007年第2期25卷 181-186页

作者： jing Luo Xian-hong Wang ji li Xiao-jiang zhao Fo-song Wang State Key Laboratory of Polymer Physicsand Chemistry Changchun Institute of Applied Chermstry Graduate School of Chinese Academy of Sciences Changchun 130022 China

Electrostatic interaction conductive hybrids were prepared in water/ethanol solution by the sol-gel process from inorganic sol containing carboxyl group and water-borne conductive polyaniline （cPANI）. The electrostatic interaction hybrids film displayed 1-2 orders of magnitude higher electrical conductivity in comparison with common hybrids film, showing remarkable conductivity stability against water soaking. Most strikingly, it displayed ideal electrochemical activity even in a solution with pH = 14, which enlarged the conducting polyaniline application window to strong alkaline media.

关键词： Water-borne conductive polyaniline Sol-gel Electrostatic interaction.

Studies on Rheological, Thermal, and Mechanical Properties of Polylactide/Methyl Methacrylate-Butadiene-Styrene Copolymer/Poly(propylene carbonate) Polyurethane Ternary Blends

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Chinese Journal of Polymer Science 2019年第12期37卷 1273-1282,I0007页

作者： ji-li zhao Hong-Wei Pan Hui-li Yang Jun-jia Bian Hui-liang Zhang Ge Gao li-Song Dong College of Chemistry Jilin UniversityChangchun 130012China Department of Science Beihua UniversityJilin 132013China Key Laboratory of Polymer Ecomaterials Chinese Academy of SciencesChangchun Institute of Applied ChemistryChangchun 130022China Zhejiang Zhongke Applied Chemistry Technology Co. Ltd.Hangzhou 310000China

Polylactide(PLA),methyl methacrylate-butadiene-styrene copolymer(MBS),and poly(propylene carbonate)polyurethane(PPCU)were blended and subjected to blown film *** rheological,mechanical,morphological,thermal,and crystalline properties of the PLA/MBS/PPCU ternary blends and the mechanical properties of the resulting films were *** of mechanical test showed that PPCU and MBS could synergistically toughen *** impact strength of 50/10/40 PLA/MBS/PPCU blend(74.7 k J/m^2)was about 7.5 times higher than that of the neat PLA(10.8 k J/m^2),and the elongation at break of 50/10/40 PLA/MBS/PPCU blend(276.5%)was higher by about 45 times that of PLA(6.2%).The tear strength of PLA/MBS/PPCU films was 20 k N/m higher than that of PLA,and the elongation at break(MD/TD)of 50/10/40 PLA/MBS/PPCU films was 271.1%/222.3%,whereas that of PLA was only 2.7%/3.0%.POM observations displayed that the density of spherulite nucleation increased and the size of crystalline particles decreased with the addition of *** increasing PPCU content from 5%to 20%,the density of spherulite nucleation increased and the size of crystalline particles decreased continuously,but the nucleation density of spherulites was slightly lowered with increasing PPCU content from 30%to 40%.The PLA/MBS/PPCU films exhibited excellent mechanical properties,which expanded the application range of these biodegradable films.

关键词： Biodegradable Polylactide Poly(propylene carbonate)polyurethane Methyl methacrylate-butadiene-styrene copolymer Films

Threshold Selection and Resource Allocation for Quantized Identification

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Journal of Systems Science & Complexity 2024年第1期37卷 204-229页

作者： WANG Ying li Xin zhao Yanlong ZHANG ji-Feng Key Laboratory of Systems and Control Institute of Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

This paper is concerned with the optimal threshold selection and resource allocation problems of quantized identification, whose aims are improving identification efficiency under limited resources. Firstly, the first-order asymptotically optimal quantized identification theory is extended to the weak persistent excitation condition. Secondly, the characteristics of time and space complexities are established based on the Cramér-Rao lower bound of quantized systems. On these basis, the optimal selection methods of fixed thresholds and adaptive thresholds are established under aperiodic signals, which answer how to achieve the best efficiency of quantized identification under the same time and space complexity. In addition, based on the principle of maximizing the identification efficiency under a given resource, the optimal resource allocation methods of quantized identification are given for the cases of fixed thresholds and adaptive thresholds, respectively, which show how to balance time and space complexity to realize the best identification efficiency of quantized identification.

关键词： Quantized output resource allocation system identification threshold selection.

Nonlinear Dynamics of Torsional Vibration for Rolling Mill′s Main Drive System Under Parametric Excitation

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Journal of Iron and Steel Research International 2013年第1期20卷 7-12页

作者： SHI Pei-ming li ji-zhao jiANG jin-shui liU Bin HAN Dong-ying College of Electrical Engineering Yanshan University College of Vehicles and Energy Yanshan University

The jointed shaft in the drivelines of the rolling mill, with its angle continuously varying in the production, has obvious impact on the stability of the main drive system. Considering the effect caused by the joint angle and friction force of roller gap, the nonlinear vibration model of the main drive system which contains parametric excitation stiffness and nonlinear friction damping was established. The amplitude-frequency characteristic equation and bifurcation response equation were obtained by using the method of multiple scales. Depending on the bifurcation response equation, the transition set and the topology structure of bifurcation curve of the system were obtained by using the singularity theory. The transition set can separate the system into seven areas, which has different bifurcation forms respectively. By taking the 1 780 rolling mill of Chengde Steel Co for example, the simulation and analysis were performed. The amplitude-frequency curves under different joint angles, damping coefficients, and nonlinear stiffness were given. The variations of these parameters have strong influences on the stability of electromechanical resonances and the characteristic of the response curves. The best angle of the jointed shaft is 4.761 3° in this rolling mill.

关键词： rolling mill main drive system torsional vibration parametric excitation joint angle singularity

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发酵液中吡咯分离提纯研究

精细化工中间体 2024年第4期54卷 52-56页

作者：韩昭武李吉照高海军张万忠赵东旭沈阳化工大学化学工程学院辽宁沈阳110142 北京理工大学生命学院北京100081

吡咯是现代化工制药工业中的重要原料,探索极具潜力的生物合成法中的吡咯提纯方法具有重要实践价值。采用萃取和蒸馏两种分离方法,主要围绕萃取剂的选择、萃取条件的优化、蒸馏条件的优化等内容开展提纯研究,辅以高效液相色谱法和质谱... 详细信息

吡咯是现代化工制药工业中的重要原料,探索极具潜力的生物合成法中的吡咯提纯方法具有重要实践价值。采用萃取和蒸馏两种分离方法,主要围绕萃取剂的选择、萃取条件的优化、蒸馏条件的优化等内容开展提纯研究,辅以高效液相色谱法和质谱法两种分析方法。最终选择二氯甲烷为萃取剂,室温萃取3次,在25℃、真空度0.07MPa条件下进行减压蒸馏,得到高纯度吡咯样品,收率94.4%。

关键词：吡咯发酵液二氯甲烷萃取减压蒸馏

A study on carbon emission calculation in operation stage of residential buildings based on micro electricity usage behavior:Three case studies in China

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Building Simulation 2024年第1期17卷 147-164页

作者： Menghan Niu Ying ji Miao zhao jiefan Gu Aonan li Beijing Key Laboratory of Green Built Environment and Energy Efficient Technology Beijing University of TechnologyBeijing 100124China College of Architecture and Urban Planning Tongji UniversityShanghai 201804China The Bartlett School of Architecture University College LondonWC1E 6BTUK

Along with the improvement of social productivity and living standard,residential buildings generate a growing portion of carbon emissions,especially during the operation ***,energy use behaviors are usually ignored in carbon emission *** study focuses on calculating carbon emissions during the operation stage for residential buildings based on the characteristics of energy use behaviors in different ***,we investigated energy use behaviors in dwellings across three cities in China:Xi'an,Shanghai and ***,we established calibrated carbon emission models and optimization models with different green building measures for residential *** results of this research reveal a significant disparity between the energy usage habits of residents in different climate *** carbon emissions of residential electricity bills in Xi'an,Shanghai and Fuzhou are 13.6 kgCO_(2)/(m^(2)·a)(excluding central heating),29.3 kgCO_(2)/(m^(2)·a)and 17.2 kgCO_(2)/(m^(2)·a),*** carbon emissions account for 32.2%-64.1% of the *** comparison to the model based on internal standard setting,the accuracy of the models using actual internal has improved by 25.9%-37.4%.The three-star green building methods have the highest carbon reduction rate among different star buildings,the emission reduction rates are around 30%.This study's findings are useful for carbon emission calculation and green building design of residential buildings in the future.

关键词： residential building energy usage behavior energy simulation carbon emissions

Vibration Reduction by a Partitioned Dynamic Vibration Absorber with Acoustic Black Hole Features

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Chinese Journal of Mechanical Engineering 2024年第4期37卷 120-134页

作者： Xiaoning zhao Chaoyan Wang Hongli ji jinhao Qiu li Cheng State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China Nanjing Institute of Information Technology Nanjing 210016China Department of mechanical Engineering Hong Kong Polytechnic UniversityKowloon 999077Hong KongChina

Vibration quality is a vital indicator for assessing the progress of modern *** dynamic vibration absorber(DVA)based on the acoustic black hole(ABH)feature is a new passive control method that manipulates *** offers efficient energy focalization and broad-spectrum vibration suppression,making it highly promising for applications in large equipment such as aircraft,trains,and *** previous advancements in ABH-DVA development,certain challenges remain,particularly in ensuring effective coupling with host structures during *** address these issues,this study proposes a partitioned ABH-featured dynamic vibration absorber(PABH-DVA)with partitions in the radial direction of the *** employing a plate as the host structure,simulations and experiments were conducted,demonstrating that the PABH-DVA outperforms the original symmetric ABH-DVA in terms of damping *** study also calculated and compared the coupling coefficients of the two ABH-DVAs to uncover the mechanism behind the enhanced *** results revealed that the PABH-DVA exhibits more coupled modes,occasionally with lower coupling coefficients than the symmetric *** influence of frequency ratio and modal mass was further analyzed to explain the reasons behind the PABH-DVA's superior damping ***,the study discussed the impact of the number of slits and their *** research further explains the coupling mechanism between the ABH-DVA and the controlled structure,and provides new ideas for the further application of ABH in engineering.

关键词： Acoustic black hole Vibration control Dynamic vibration absorber Coupling analysis

Intermetallic Compounds Formation in Dissimilar Friction Stir Welding of Mg/Cu Alloys

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Acta Metallurgica Sinica(English Letters) 2024年第9期37卷 1523-1532页

作者： Xue li Qingzhen zhao Hao Su ji Chen Chuansong Wu MOE Key Lab for liquid-Solid Structure Evolution and Materials Processing Institute of Materials JoiningShandong UniversityJinan250061China

Joining dissimilar Mg/Cu alloys was still an intractable problem because of the excessive intermetallic compounds(IMCs)and poor mechanical properties using conventional welding *** the present study,friction stir welding was employed for the butt joining of dissimilar AZ31B Mg-alloy and T2 pure Cu ***-free Mg/Cu joints were obtained with Mg-RS and Cu-AS configuration,at a welding speed of 50 mm/min and tool rotating speeds of 325 r/min,625 r/min and 925 r/*** the joining interface,both Mg_(2)Cu and MgCu_(2) IMC phases were observed,with a clear,uniform and continuous IMCs layer composed of two sub-layers,layer-A of Mg+Mg_(2)Cu and layer-B of Mg_(2)Cu+MgCu_(2).The maximum ultimate tensile strength of the Mg/Cu friction stir welding joint reached 130 MPa at 925 r/min due to enhanced mechanical interlocking between Mg and Cu,as well as sufficient metallurgical bonding at the joining interface with an IMCs layer thickness in the range of 1.0-2.0μm.

关键词： Friction stir welding Magnesium Copper Intermetallic compounds Mechanical properties

Investigating effect of coke porosity on blast furnace performance based on multi-physical fields

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Journal of Iron and Steel Research International 2024年第2期31卷 357-367页

作者： ji Chen zhao Lei Zhe Yao li Wang Qiang ling Ping Cui Anhui Province Key Laboratory of Coal Clean Conversion and High Valued Utilization School of Chemistry and Chemical EngineeringAnhui University of TechnologyMa’anshan243002AnhuiChina Shanxi Academy of Printing Technology Research Institute Co. Ltd.Xi’an710077ShaanxiChina

Reducing coke use is an effective measure to reduce carbon emission and energy consumption in the blast furnace(BF)***,BF is a high-temperature moving bed reactor,where complex physical transformations coupled with complicated reactions *** makes it challenging to investigate the factors determining BF performance with the conventional method.A multi-physical field coupling mathematical model of BF was thus developed to describe its mass and heat transfer as well as its intrinsic ***,the proposed model was validated with the production *** coupling conditions,influences of dominating reactions on BF performance(temperature distribution,gas distribution,iron formation reaction,and direct reduction degree)were *** results indicated that coke combustion,indirect reduction,and direct reduction of iron ore mainly took place nearby the shaft tuyere,cohesive zone,and dripping zone,***,the rate of coke solution loss reaction was increased with the rising coke porosity in the cohesive *** the effect of coke porosity on the efficiency and stability of BF,the coke porosity of 0.42 was regarded as a reasonable value.

关键词： Blast furnace Mathematical model Multi-physical field Simulation Coke porosity