检索结果-南通市图书馆

Preparation technologies for polymer composites with high-directional thermal conductivity:A review

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第11期17卷 9796-9814页

作者： Yanshuai Duan huitao yu Fei Zhang Mengmeng Qin Wei Feng School of Materials Science and Engineering and Tianjin Key Laboratory of Composite and Functional Materials Tianjin University Tianjin 300350 China Institute of Flexible Electronics Technology of THU Jiaxing 314000 China

With the rapid development of science and technology,electronic devices are moving towards miniaturization and integration,which brings high heat dissipation *** the heat dissipation process of a heating element,heat may spread to adjacent components,causing a decrease in the performance of the *** avoid this situation,the ability to directionally transfer heat energy is urgently ***,thermal interface materials(TIMs)with directional high thermal conductivity are more critical in thermal management system of electronic *** decades,many efforts have been devoted to the design and fabrication of TIMs with high-directional thermal *** from the advantage in feasibility,low-cost and scalability,compositing with thermal conductive fillers has been proved to be promising strategy for fabricating the high-directional thermal conductive *** review summarizes the present preparation technologies of polymer composites with high-directional thermal conductivity based on structural engineering of thermal conductive fillers,focusing on the manufacturing process,mechanisms,achievements,advantages and disadvantages of different ***,we summarize the existing problems and potential challenges in the field of directional high thermal conductivity composites.

关键词： preparation technologies directional networks polymer composites high-directional thermal conductivity

Hyperelastic Graphene Aerogels Reinforced by In‑suit Welding Polyimide Nano Fiber with Leaf Skeleton Structure and Adjustable Thermal Conductivity for Morphology and Temperature Sensing

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advanced Fiber Materials 2023年第3期5卷 1037-1049页

作者： Weida Yin Mengmeng Qin huitao yu Jinxu Sun Wei Feng School of Materials Science and Engineering and Tianjin Key Laboratory of Composite and Functional Materials Tianjin UniversityTianjin 300350People’s Republic of China

Graphene-aerogel-based flexible sensors have heat tolerances and electric-resistance sensitivities superior to those of polymer-based ***,graphene sheets are prone to slips under repeated compression due to inadequate chemical *** addition,the heat-transfer performance of existing compression strain sensors under stress is unclear and lacks research,making it difficult to perform real-temperature *** address these issues,a hyperelastic polyimide fiber/graphene aerogel(PINF/GA)with a three-dimensional interconnected structure was fabricated by simple one-pot compound-ing and in-situ welding *** welding of fiber lap joints promotes in-suit formation of three-dimensional crosslinked networks of polyimide fibers,which can effectively avoid slidings between fibers to form reinforced ribs,preventing graphene from damage during *** particular,the inner core of the fiber maintains its macromolecular chain structure and toughness during ***,PINF/GA has good structural stabilities under a large strain compression(99%).Moreover,the thermal and electrical conductivities of PINF/GA could not only change with various stresses and strains but also keep the change steady at specific stresses and strains,with its thermal-conductivity change ratio reaching up to *** PINF/GA,with dynamically stable thermal and electrical conductivity,as well as high heat tolerance,shows broad applica-tion prospects as sensors in detecting the shapes and temperatures of unknown objects in extreme environments.

关键词： Graphene aerogel Fiber welding Highly compressible High and low temperature resistance Cyclic stability Flexible tactile sensor

Water-resistant conductive organogels with sensation and actuation functions for artificial neuro-sensory muscular systems

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

SmartMat 2022年第4期3卷 632-643页

作者： Zhixing Zhang yunfei yu huitao yu Yiyu Feng Wei Feng School of Materials Science and Engineering Tianjin UniversityTianjinChina Tianjin Key Laboratory of Composite and Functional Materials Tianjin UniversityTianjinChina Key Laboratory of Advanced Ceramics and Machining Technology Ministry of EducationTianjinChina

The development of functional flexible conductive materials can significantly contribute to the improvement of intelligent human–computer ***,it is a challenge to endow human–machine interface with perception and response actuation ***,a customizable and multifunctional electronic conductive organogel is proposed by combining conductive carbon nanotube(CNT)clusters and flexible adhesive *** conductive CNT cluster layers generated on the surface of organogels equip the resulting organogel-based conductors with considerable quasi-superhydrophobicity and increase their potential applicability as highly sensitive stress and strain *** particular,this quasi-superhydrophobicity is insensitive to tensile *** on customizable conductive networks and entropy-driven organogel actuation,the conductive organogels can sense various strain and stress signals and imitate natural organisms with muscle actuation and *** strategy for preparing electronic conductors can enhance the rational design of soft robotics and artificial intelligence devices,facilitating further progress of human-like intelligent systems.

关键词： actuation adhesive organogel carbon nanotube cluster flexible sensor sensation

Highly Thermally Conductive Polymer/Graphene Composites with Rapid Room‑Temperature Self‑Healing Capacity

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano-Micro Letters 2022年第8期14卷 194-207页

作者： huitao yu Can Chen Jinxu Sun Heng Zhang Yiyu Feng Mengmeng Qin Wei Feng School of Materials Science and Engineering and Tianjin Key Laboratory of Composite and Functional Materials Tianjin UniversityTianjin 300350People’s Republic of China Key Laboratory of Materials Processing and Mold Ministry of EducationZhengzhou UniversityZhengzhou 450002People’s Republic of China

Composites that can rapidly self-healing their structure and function at room temperature have broad application ***,in view of the complexity of composite structure and composition,its self-heal is facing *** this article,supramolecular effect is proposed to repair the multistage structure,mechanical and thermal properties of composite materials.A stiff and tough supramolecular frameworks of 2-[[(butylamino)carbonyl]oxy]ethyl ester(PBA)–polydimethylsiloxane(PDMS)were established using a chain extender with double amide bonds in a side chain to extend prepolymers through ***,by introducing the copolymer into a folded graphene film(FGf),a highly thermally conductive composite of PBA–PDMS/FGf with self-healing capacity was *** ratio of crosslinking and hydrogen bonding was optimized to ensure that PBA–PDMS could completely self-heal at room temperature in 10 ***,PBA–PDMS/FGf exhibits a high tensile strength of 2.23±0.15 MPa at break and high thermal conductivity of 13±0.2 W m^(−1)K^(−1);of which the self-healing efficiencies were 100%and 98.65%at room temperature for tensile strength and thermal conductivity,*** excellent self-healing performance comes from the efficient supramolecular interaction between polymer molecules,as well as polymer molecule and *** kind of thermal conductive self-healing composite has important application prospects in the heat dissipation field of next generation electronic devices in the future.

关键词： Carbon/polymer composites Self-healing capacity High thermal conductivity Molecular simulation Room temperature

Co-Harvest Phase-Change Enthalpy and Isomerization Energy for High-Energy Heat Output by Controlling Crystallization of Alkyl-Grafted Azobenzene Molecules

在线全文

学校读者我要写书评

暂无评论

Energy & Environmental Materials 2024年第3期7卷 415-424页

作者： Jian Gao Yiyu Feng Wenyu Fang Hui Wang Jing Ge Xiaoyu Yang huitao yu Mengmeng Qin Wei Feng School of Materials Science and Engineering Tianjin UniversityTianjin 300350China Key Laboratory of Materials Processing and Mold Ministry of EducationZhengzhou UniversityZhengzhou 450002China

Photoisomerization-induced phase change are important for co-harvesting the latent heat and isomerization energy of azobenzene *** optimizing heat output and energy delivery at alternating temperatures are challenging because of the differences in crystallizability and *** article reports two series of asymmetrically alkyl-grafted azobenzene(Azo-g),with and without a methyl group,that have an optically triggered phase *** exothermic modes were designed to utilize crystallization enthalpy(△H_(c))and photothermal(isomerization)energy(△H_(p))at different temperatures determined by the ***-g has high heat output(275-303 J g^(-1))by synchronously releasing△H_(c)and△H_(p)over a wide temperature range(-79℃to 25℃).We fabricated a new distributed energy utilization and delivery system to realize a temperature increase of 6.6℃at a temperature of-8℃.The findings offer insight into selective utilization of latent heat and isomerization energy by molecular optimization of crystallization and isomerization processes.

关键词： crystallizability distributed energy utilization system energy density exothermic modes isomerization

Flexible and elastic thermal regulator for multimode intelligent temperature control

在线全文

学校读者我要写书评

暂无评论

SusMat 2023年第6期3卷 843-858页

作者： Can Chen huitao yu Tao Lai Jun Guo Mengmeng Qin Zhiguo Qu Yiyu Feng Wei Feng Tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjinP.R.China MOE Key Laboratory of Thermo-Fluid Science and Engineering School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’anP.R.China

As nonlinear thermal devices,thermal regulators can intelligently respond to temperature and control heat flow through changes in heat transfer capacities,which allows them to reduce energy consumption without external ***,current thermal regulators generally based on high-quality crystallinestructure transitions are intrinsically rigid,which may cause structural damage and functional failure under mechanical strain;moreover,they are difficult to integrate into emerging soft electronic *** this study,we develop a flexible,elastic thermal regulator based on the reversible thermally induced deformation of a liquid crystal elastomer/liquid metal(LCE/LM)composite *** adjusting the crosslinking densities,the LCE foam exhibits a high actuation strain of 121%with flexibility below the nematic–isotropic phase transition temperature(TNI)and hyperelasticity above *** incorporation of LMresults in a high thermal resistance switching ratio of 3.8 over a wide working temperature window of 60◦C with good cycling *** feature originates from the synergistic effect of fragmentation and recombination of the internal LM network and lengthening and shortening of the bond line ***,we fabricate a“grid window”utilizing photic-thermal integrated thermal control,achieving a superior heat supply of 13.7℃ at a light intensity of 180mW/cm^(2)and a thermal protection of 43.4℃at 1200 mW/cm^(2).The proposed method meets the mechanical softness requirements of thermal regulatormaterials with multimode intelligent temperature control.

关键词： intelligent temperature control liquid crystal elastomer liquid metal thermal regulator thermomechanical coupling

Tailoring Iron-Ion Release of Cellulose-Based Aerogel-Coated Iron Foam for Long-Term High-Power Microbial Fuel Cells

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Transactions of Tianjin University 2024年第5期30卷 436-447页

作者： Zhengyang Ni huitao yu Haoran Wang Mengmeng Qin Feng Li Hao Song Xiangyu Chen Yiyu Feng Wei Feng School of Material Science and Engineering Tianjin UniversityTianjin 300350China School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 100083China

The presence of iron(Fe) has been found to favor power generation in microbial fuel cells(MFCs). To achieve long-term power production in MFCs, it is crucial to effectively tailor the release of Fe ions over extended operating periods. In this study, we developed a composite anode(A/IF) by coating iron foam with cellulose-based aerogel. The concentration of Fe ions in the anode solution of A/IF anode reaches 0.280 μg/mL(Fe^(2+) vs. Fe^(3+) = 61%:39%) after 720 h of aseptic primary cell operation. This value was significantly higher than that(0.198 μg/mL, Fe^(2+) vs. Fe^(3+) = 92%:8%) on uncoated iron foam(IF), indicating a continuous release of Fe ions over long-term operation. Notably, the resulting MFCs hybrid cell exhibited a 23% reduction in Fe ion concentration(compared to a 47% reduction for the IF anode) during the sixth testing cycle(600-720 h). It achieved a high-power density of 301 ± 55 mW/m^(2) at 720 h, which was 2.62 times higher than that of the IF anode during the same period. Furthermore, a sedimentary microbial fuel cell(SMFCs) was constructed in a marine environment, and the A/IF anode demonstrated a power density of 103 ± 3 mW/m^(2) at 3240 h, representing a 75% improvement over the IF anode. These findings elucidate the significant enhancement in long-term power production performance of MFCs achieved through effective tailoring of Fe ions release during operation.

关键词： Microbial fuel cells Coating Fe ions Tailor release Long-term

Three-Dimensional N-Doped Carbon Nanotube/Graphene Composite Aerogel Anode to Develop High-Power Microbial Fuel Cell

在线全文

学校读者我要写书评

暂无评论

Energy & Environmental Materials 2023年第3期6卷 161-169页

作者： Shixuan Jin Yiyu Feng Jichao Jia Fulai Zhao Zijie Wu Peng Long Feng Li huitao yu Chi Yang Qijing Liu Baocai Zhang Hao Song Wei Feng School of Material Science and Engineering Tianjin UniversityTianjin 300350China School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China

Optimizing the structure of electrode materials is one of the most effective strategies for designing high-power microbial fuel cells(MFCs).However,electrode materials currently suffer from a series of shortcomings that limit the output of MFCs,such as high intrinsic resistance,poor electrolyte wettability,and low microbial load ***,a three-dimensional(3D)nitrogen-doped multiwalled carbon nanotube/graphene(N-MWCNT/GA)composite aerogel is synthesized as the anode for *** nitrogen-doped GA,MWCNT/GA,and N-MWCNT/GA,the macroporous hydrophilic N-MWCNT/GA electrode with an average pore size of 4.24μm enables high-density loading of the microbes and facilitates extracellular electron transfer with low intrinsic ***,the hydrophilic surface of N-MWCNT can generate high charge mobility,enabling a high-power output performance of the *** consequence,the MFC system based on N-MWCNT/GA anode exhibits a peak power density and output voltage of 2977.8 mW m^(−2)and 0.654 V,which are 1.83 times and 16.3%higher than those obtained with MWCNT/GA,*** results demonstrate that 3D N-MWCNT/GA anodes can be developed for high-power MFCs in different environments by optimizing their chemical and microstructures.

关键词： anode graphene aerogel microbial fuel cell N-doped carbon nanotube

Motion mechanism and gait planning of a wheeled micro robot

在线全文

学校读者我要写书评

暂无评论

Journal of Southeast University(English Edition) 2006年第2期22卷 191-195页

作者：于会涛马培荪何冬青上海交通大学机器人研究所上海200030

Based on a novel shape memory alloy （SMA） actuator, a micro worming robot is presented. The robot adopts a wheeled moving mechanism. The principle of the robot＇s enlarged pace is introduced, and the structure and motion mechanism of the SMA actuator and the wheeled moving mechanism are discussed. The gait about the robot＇s rectilinear movement and turning movement is also planned. Under the effect of the eccentric wheel self-locking mechanisms and changing-direction mechanisms, the robot can move forward and backward, and turn actively, which overcomes the disadvantages of the traditional SMA micro robots to a certain extent. Furthermore, some experiments on the heating current of the SMA actuator and the robot＇s motion capability are carded out.

关键词： micro robot shape memory alloy actuator wheeled gait planning