检索结果-南通市图书馆

Numerical Analysis of Energy Effect in Laser-TIG Hybrid Welding

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2003年第Z1期19卷 23-26页

作者： Yanbin CHEN liqun li Junfei fang Xiaosong feng National Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 Chlna National Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 Chlna National Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 Chlna National Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 Chlna

The hybrid source that combined CO2 laser with TIG arc to proceed welding was analyzed. Based on an energymodel, the temperature field and weld shape were calculated numerically. The heat transfer characteristic of thehybrid heat source to workpiece and its effect to weld shape were also analyzed. Through analyzing the enhancementeffect of the hybrid heat source, the absorption effect and defocusing effect of the hybrid arc to laser were calculated,and the regularity of the energy density to the current was obtained subsequently. At last, the critical energy matchesto induce the enhancement effect of CO2 laser-TIG arc hybrid welding were obtained.

关键词： Laser-TIG hybrid welding, Energy effect, Numerical simulation

IMPROVING THE PROPERTIES OF HDPE BASED SEPARATORS FOR liTHIUM ION BATTERIES BY BLENDING BLOCK WITH COPOLYMER PE-b-PEG

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2013年第2期31卷 309-317页

作者： Jun-li Shi Hao li li-feng fang Zhi-ying liang 朱宝库 Department of Polymer Science and Engineering ERC of Membrane and Water Treatment Technology Key Laboratory of Macromolecular Synthesis and Functionalization MOE Zhejiang University

To improve the performances of HDPE-based separators, polyether chains were incorporated into HDPE membranes by blending with poly（ethylene-block-ethylene glycol）（PE-b-PEG） via thermally induced phase separation （TIPS） process. By measuring the composition, morphology, crystallinity, ion conductivity, etc, the influence of PE-b-PEG on structures and properties of the blend separator were investigated. It was found that the incorporated PEG chains yielded higher surface energy for HDPE separator and improved affinity to liquid electrolyte. Thus, the stability of liquid electrolyte trapped in separator was increased while the interfacial resistance between separator and electrode was reduced effectively. The ionic conductivity of liquid electrolyte soaked separator could reach 1.28 ×10^-3 ***^-1 at 25℃, and the electrochemical stability window was up to 4.5 V （versus li^＋/li）. These results revealed that blending PE-b-PEG into porous HDPE membranes could efficiently improve the performances of PE separators for lithium batteries.

关键词： Polyethylene Poly(ethylene-block-ethylene glycol) copolymer Blend porous separator Thermally inducedphase separation lithium ion battery separator.

A construction of inter-group complementary codes with flexible ZCZ length

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第10期12卷 846-854页

作者： li-fang feng Xian-wei ZHOU Ping-zhi FAN School of Information Engineering University of Science and Technology Beijing Beijing 100083 China Provincial Key Lab of Information Coding and Transmission Institute of Mobile Communications Southwest Jiaotong University Chengdu 610031 China

A general construction of inter-group complementary (IGC) codes is proposed based on perfect complementary (PC) codes,interleaving operation,and the orthogonal *** correlation properties of the newly constructed IGC codes can be described as follows:(1) the autocorrelation sidelobes of the codes are zeros in the zero correlation zone (ZCZ);(2) the cross-correlation functions (CCFs) between any two different codes of the same group are zeros in the ZCZ;(3) the CCFs between any two codes of different groups are zeros *** key point of this construction is that the ZCZ length of the generated IGC codes can be chosen *** is well known that there is a limitation between the ZCZ length and the number of mates;that is,the smaller is the length of ZCZ,the more are the IGC codes that can be ***,if we can choose the ZCZ length of the IGC codes flexibly according to the requirement of the system,more users can be accommodated in the system.

关键词： Z-complementary codes Perfect complementary codes Zero correlation zone

Poly(N,N-dimethylaminoethyl methacrylate) Grafted Poly(vinyl chloride)s Synthesized via ATRP Process and Their Membranes for Dye Separation

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2015年第11期33卷 1491-1491,1492-1502页

作者： li-feng fang Na-chuan Wang Ming-yong Zhou 朱宝库 li-ping Zhu Angelin Ebanezar John Key Laboratory of Macromolecular Synthesis and Functionalization (Ministry of Education) Engineering Research Center of Membrane and Water Treatment (Ministry of Education) Department of Polymer Science and Engineering Zhejiang University

To functionalize poly（vinyl chloride）（PVC） for various applications, monomers containing tertiary amine group are incorporated into PVC via atom transfer radical polymerization（ATRP） initiated by the labile chlorines in their backbones. The kinetics of synthesis was carefully investigated, and it is proven that the grafting polymerization process can be effectively controlled by regulating the reaction time. The membranes are fabricated using PVC and copolymers by non-solvent induced phase separation（NIPS） process. The hydrophilicity and pore structure of copolymer membranes were enhanced as well, these membranes are endowed with positive charge. When PDMA%（i.e., the PDMA weight percentage in copolymer） is 31.1%, the flux and Victoria blue B rejection are 26.0 L·m·^-2·h^-1（0.5 MPa） and 91.2%, respectively. Thus, the newly synthesized polymer is proven to be a promising material for dye separation with positive charges.

关键词： Poly(vinyl chloride) Poly(N N-dimethylaminoethyl methacrylate) Non-solvent induced phase separation Dye separation

Effect of Ag and Ni on the melting point and solderability of SnSbCu solder alloys

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2009年第6期16卷 691-695页

作者： Yan-fu Yan Yan-sheng Wang li-fang feng Ke-xing Song Jiu-ba Wen Henan Key Laboratory of Advanced Non-ferrous Metals Luoyang 471003 China Architecture and Civil Engineering Institute Henan University of Science and Technology Luoyang 471003 China

To improve the properties of Sn10Sb8Cu solder alloy, two new solders （SnSbCuAg and SnSbCuNi） were formed by adding small amounts of Ag or Ni into the solder alloy. The results show that the melting point of the SnSbCuAg solder alloy decreases by 14.1℃ and the spreading area increases by 16.5% compared to the matrix solder. The melting point of the SnSbCuNi solder alloy decreases by 5.4℃ and the spreading area is slightly less than that of the matrix solder. Microstructure analysis shows that adding trace Ag makes the melting point decline due to the dispersed distribution of SnAg phase with low melting point. Adding trace Ni, Cu6Sn5 and （Cu, Ni）6Sn5 with polyhedron shape on the copper substrate can be easily seen in the SnSbCuNi solder alloy, which makes the viscosity of the melting solder increase and the spreading property of the solder decline.

关键词： solder alloy Ag Ni melting point solderability

Single-atom sites regulation by the second-shell doping for efficient electrochemical CO_(2)reduction

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第9期35卷 360-363页

作者： Qian-Qian Tang li-fang feng Zhi-Peng li Shi-Hao Wu Long-Shuai Zhang Qing Sun Mei-feng Wu Jian-Ping Zou Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle Nanchang Hangkong UniversityNanchang 330063China National-Local Joint Engineering Research Center of Heavy Metals Pollutants Control and Resource Utilization Nanchang Hangkong UniversityNanchang 330063China

Nitrogen-doped carbon loaded single-atom catalysts(SACs)are promising candidates for electrocatalytic conversion of CO_(2)into high-valuable chemicals,and the modification of catalysts by heteroatom-doping strategy is an effective approach to enhance the CO_(2)reduction ***,the large difference exists in atomic radius between nitrogen atoms and the doped heteroatoms may lead to the poor stability of active *** this study,we have synthesized a Ni single atom catalyst with S doping at the secondshell on the ultrathin carbon nanosheets support(Ni-N_(4)-SC)by solid-phase *** S atom in the second-shell contributes to the higher efficiency of CO_(2)conversion at lower potentials while the Ni-N_(4)-SC can be more *** experimental results and theoretical calculations indicate that the S atom in second-shell breaks the uniform charge distribution and reduces the free energy of hydrogenation,which can increase the adsorption of CO_(2),accelerate charge transfer,and reduce the reaction energy *** work reveals the close relationship between the second-shell and the electrocatalytic activity of single atom sites,which also provides a new perspective to design efficient single atom catalysts.

关键词： Single-atom catalyst Heteroatom-doping Second shell CO_(2)electroreduction Electronic structure regulation

A lithiated gel polymer electrolyte with superior interfacial performance for safe and long-life lithium metal battery

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2021年第4期30卷 313-322页

作者： Jia-Jia Yuan Chuang-Chao Sun li-feng fang You-Zhi Song Yan Yan Ze-lin Qiu Yu-Jie Shen Han-Ying li Bao-Ku Zhu Key Laboratory of Macromolecular Synthesis and Functionalization(Ministry of Education) Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027ZhejiangChina Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China

Rechargeable lithium metal batteries(LMBs)have gained much attention ***,the short lifespan and safety issues restrict their commercial *** we report a novel gel polymer electrolyte(GPE)based on lithiated poly(vinyl chloride-r-acrylic acid)(PVCAAli)to realize dendritesuppressing and long-term stable lithium metal *** chains ensure the quick gelation process and high electrolyte uptake,and lithiated PAA segments enable the increase of mechanical strength,acceleration of lithium-ion transmission and improvement of interfacial *** GPE showed much higher mechanical strength compared with other free-standing GPEs in previous *** displays a superior ionic conductivity of 1.50 m S cm^(-1) and a high lithium-ion transference number of 0.59 at room ***,the lithiated GPE exhibits excellent interfacial compatibility with lithium metal *** symmetrical cells with PVCAAli GPE yield low hysteresis of 50 m V over1000 h at 1.0 m A cm^(-2).And the possible mechanism of the lithiated GPE with improved lithium-ion transfer and interfacial property was ***,both the li4Ti5O12/li and lithium-sulfur(li-S)cells assembled with PVCAAli GPE show outstanding electrochemical performance,retaining high discharge capacities of 133.8 m Ah g^(-1) and 603.8 m Ah g^(-1) over 200 cycles,*** work proves excellent application potential of the highly effective and low-cost PVCAAli GPE in safe and long-life LMBs.

关键词： lithiation Gel polymer electrolyte lithium dendrite Safety lithium metal battery

Copolymer-assisted Polypropylene Separator for Fast and Uniform lithium Ion Transport in lithium-ion Batteries

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2020年第12期38卷 1313-1324页

作者： Yan Yan Qing-Ran Kong Chuang-Chao Sun Jia-Jia Yuan Zheng Huang li-feng fang Bao-Ku Zhua You-Zhi Song Key Laboratory of Macromolecule Synthesis and Functionalization(Ministry of Education) ERC of Membrane and Water Treatment(Ministry of Education)Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China Institute ofNuclear and New Energy Technology Tsinghua UniversityBeijing W0084China

In lithium-ion batteries(liBs),separators play a vital role in lithium-ion(li+)transport,and thus affect rate performance,battery life,and ***,a new kind of multifunctional copolymer poly(acrylonitrile-co-lithium acrylate-co-butyl acrylate)(PAAB-li)is synthesized through soap-free emulsion polymerization,and is used to form homogeneous-covered separator based on PP matrix by a simple dip-annealing *** to the bare PP separator,the modified separators with PAAB-li enable higher ionic conductivity,higher lithium ion transference number(increased from 0.360 to 0.525),and lower interface impedance(reduced from 155Ω to 34Ω).It has been indicated that PAAB-li functional layer significantly promotes the fast transport of li+and improves the compatibility of the separator/electrolyte-electrode *** liCo02/graphite cells with the PAAB-li-assisted separator demonstrate excellent cycle stability and rate *** addition,the li symmetric cells with the modified separator stably cycle over 800 h,indicating the functional layer effectively suppresses the lithium dendrite *** facile strategy can be easily applied to liBs requiring high safety and even be scalable to li metal ***,the possible mechanism of the PAAB-li functional layer promoting fast and uniform li+transport is discussed in this paper.

关键词： Polyelectrolytes Polypropylene separator lithium ion transport Dendrite-free lithium-ion battery

中空纤维膜脱氧过程中Dean涡强化传质研究（英文）

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2019年第8期20卷 601-613页

作者： Qing-ran KONG Yi-zhen ZHANG Hua TIAN li-feng fang Ming-yong ZHOU li-ping ZHU Bao-ku ZHU Key Laboratory of Macromolecule Synthesis and Functionalization Ministry of Education Key Laboratory of Adsorption and Separation Materials & Technologies of Zhejiang Province ERC of Membrane and Water Treatment Ministry of Education Department of Polymer Science and Engineering Zhejiang University

目的:在螺旋中空纤维膜脱氧过程中引入了Dean涡,与线型中空纤维膜脱氧过程相比传质速率显著提升。本文旨在建立新的螺旋中空纤维膜脱氧过程传质模型,探讨管程流体雷诺数、中空纤维膜结构参数、壳程真空度和操作温度对Dean涡强化传质效... 详细信息

目的:在螺旋中空纤维膜脱氧过程中引入了Dean涡,与线型中空纤维膜脱氧过程相比传质速率显著提升。本文旨在建立新的螺旋中空纤维膜脱氧过程传质模型,探讨管程流体雷诺数、中空纤维膜结构参数、壳程真空度和操作温度对Dean涡强化传质效果的影响,并优化螺旋中空纤维膜脱氧过程操作参数。创新点:1.建立新的螺旋中空纤维膜脱氧过程传质模型;2.该传质模型可以应用于任何螺旋中空纤维膜气-液过程的传质行为描述。方法:1.实验研究管程流体雷诺数、中空纤维膜结构参数、壳程真空度和操作温度对Dean涡强化传质效果的影响,并与线型中空纤维膜传质进行对比。2.利用螺旋坐标系下的质量连续性方程以及Dean涡的摄动解描述管程溶质的传质行为;利用改进的尘气模型描述膜孔道内多组份气体的扩散行为;耦合建立新的螺旋中空纤维膜脱氧过程传质模型,并与实验结果进行比较。3.模拟脱氧过程的氧、氮、水三种组分的浓度分布,优化螺旋中空纤维膜脱氧过程的膜结构参数和操作参数。结论:1.实验和模拟结果均证实Dean涡可以有效提升脱氧传质速率,最大传质增强因子为2.2。2. Dean涡主要受到管程雷诺数和中空纤维膜曲率的影响;当管程雷诺数较大时,中空纤维膜即使存在很小的曲率,传质的速率也有显著的提升。

关键词：传质中空纤维膜水脱氧 Dean涡