检索结果-内蒙古大学图书馆

Comparative Study of Intrachain versus Interchain Cross-linking on the Mechanical,Thermal and Dielectric Properties of Low-k Polyimide

引用

Chinese Journal of Polymer Science 2024年第11期42卷 1824-1834,I0014页

作者： Wan-Jing Zhao Yi-Zhang Tong Pei-Pei Zeng Yang-Sheng Zhou Xian-Wu Cao Wei Wu National Engineering Research Center of Novel Equipment for Polymer Processing Key Laboratory of Polymer Processing Engineering of Ministry of EducationGuangdong Provincial Key Laboratory of Technique and Equipment for Macromolecular Advanced ManufacturingSchool of Mechanical and Automotive EngineeringSouth China University of TechnologyGuangzhou510640China Engineering Center for Superlubricity Jihua LaboratoryFoshan528200China Guangdong Provincial Key Laboratory of Distributed Energy Systems Guangdong Provincial Engineering Research Center of Distributed Energy SystemsDongguan University of TechnologyDongguan523808China

Polyimide(PI)is widely used in high-frequency communication technology due to its exceptional comprehensive ***,traditional PI has a relatively elevated dielectric constant and dielectric ***,the different cross-linked structures were introduced in PI matrix and conducted a detailed discussion on the influence of cross-linking agent content and cross-linking structure type on the overall performance of PI *** comparison to the dielectric constant of 2.9 of neat PI,PI with an interchain cross-linking structure containing 2 wt%1,3,5-tris(4-aminophenyl)benzene(TAPB)(interchain-PI-2)exhibited the reduced dielectric constant of 2.55 at 1 *** PI films with intrachain crosslinking structure containing 2 wt%TAPB(intrachain-PI-2)exhibited the lowest dielectric constant of 2.35 and the minimum dielectric loss of0.0075 at 1 *** was due to the more entanglement junctions of intrachain-PI resulting in decreased carrier *** thermal expansion coefficients of both interchain-PI and intrachain-PI films were effectively ***,in contrast to interchain-PI films,the intrachain-PI films maintained colorlessness and transparency as the cross-linking agent content *** work compared the effects of two different cross-linked structures on the performance of PI films and provided a feasible way to obtain low-k PI films with excellent comprehensive performance for 5G applications.

关键词： Interchain cross-linking Intrachain cross-linking Polyimide Low dielectric

来源：评论

学校读者我要写书评

暂无评论

Evaluation of Surface Roughness of Aluminum Alloy in Burnishing Process Based on Chaos Theory

引用

Chinese Journal of Mechanical Engineering 2023年第1期36卷 90-103页

作者： Zhipeng Yuan Zhenyu Zhou Zhiguo Jiang Zeyu Zhao Cong Ding Zhongyu Piao College of Mechanical Engineering Zhejiang University of TechnologyHangzhou310012ZhejiangChina Key Laboratory of Special Purpose Equipment and Advanced Processing Technology Ministry of Education and Zhejiang ProvinceZhejiang University of TechnologyHangzhou310012China

Burnishing experiments with different burnishing parameters were performed on a computer numerical control milling machine to characterize the surface roughness of an aluminum alloy during *** chaos theory was employed to investigate the nonlinear features of the burnishing *** experimental results show that the power spectrum is broadband and continuous,and the Lyapunov exponentλis positive,proving that burnishing has chaotic *** chaotic characteristic parameter,the correlation dimension D,is sensitive to the time behavior of the system and is used to establish the corresponding relationship with the surface *** correlation dimension was the largest,when the surface roughness was the ***,when the correlation dimension curve decreases,the roughness curve *** correlation dimension and surface roughness exhibit opposite variation *** higher the correlation dimension,the lower the surface *** surface roughness of the aluminum alloy can be characterized online by calculating the correlation dimension during burnishing.

关键词： Aluminum alloy burnishing Power spectrum Correlation dimension Lyapunov exponent Surface roughness

来源：评论

学校读者我要写书评

暂无评论

Two polyoxovanadoborates with over 100 nuclei assembled from a {V_(14)Co_(12)B_(72)} cluster

引用

Science China Chemistry 2024年第8期67卷 2578-2585页

作者： Shuang-Xue Wu Yu-Jiao Dong Yang Yang Chao Qin Chun-Yi Sun Wei Guan Xin-Long Wang Zhong-Min Su Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education Northeast Normal UniversityChangchun 130024China School of Chemistry and Environmental Engineering Changchun University of Science and TechnologyChangchun 130013China Key Laboratory of Advanced Materials of Tropical Island Resources Hainan UniversityHaikou 570228China

Combining theoretical prediction and experimental exploration, the first sandwich-type polyoxovanadoborate(POVB) with an odd number of nuclei, [V_(11)B_(26)O_(73)(OH)_(10)]^(8-)(1), was discovered under hydrothermal conditions. Density-functional theory(DFT)gives a rationalization for the existence of this structure and the structural feature is consistent with the {V_NB_(2N+X)}(X = 2, 4, 6, 8)general formula. Excitingly, when Co and 1,10-phenanthroline(phen) are introduced into the synthesis of vanadoborates system,a 100-nuclei [Co_6(phen)_(10)(H_(2)O)_8][V_(14)Co_(12)B_(72)O_(144)(OH)_(20)]·28H_(2)O(2) and a 102-nuclei [Co_6(phen)_(14)(H_(2)O)_(4)][V_(14)Co_(12)B_(72)O_(144)(OH)_(20)]·23H_(2)O(3) with the same core structure of [V_(14)Co_(12)B_(72)]^(12-)are obtained. The vase-shaped [V_(14)Co_(12)B_(72)] polyanion is a multilayered sandwich-type structure containing seven distinct structural layers and is the largest known POVB. Furthermore, 2demonstrates exceptional thermal and chemical stability and serves as an efficient and stable catalyst for the photoreduction of carbon dioxide.

关键词： boronate metallic materials polyoxovanadoborates density functional theory photocatalysis CO_(2)reduction

来源：评论

学校读者我要写书评

暂无评论

Phosphorous-doped carbon nanotube/reduced graphene oxide aerogel cathode enabled by pseudocapacitance for high energy and power zinc-ion hybrid capacitors

引用

Chinese Chemical Letters 2024年第2期35卷 570-576页

作者： Junjun Yao Fuzhi Li Ruyi Zhou Chenchen Guo Xinru Liu Yirong Zhu Hunan Key Laboratory of Green Metallurgy and New Energy Materials College of Materials and Advanced ManufacturingHunan University of TechnologyZhuzhou 412007China College of packaging and Material Engineering Hunan University of TechnologyZhuzhou 412007China

The design and development of energy storage device with high energy/power density has become a research ***-ion hybrid capacitors(ZHCs)are considered as one of the most promising ***,the application of ZHCs is hindered by their low energy density at high power density due to the unsatisfactory cathode *** this study,a novel 3D phosphorus-doped carbon nanotube/reduced graphene oxide(P-CNT/rGO)aerogel cathode is synthesized through a synergistic modification strategy of CNT insertion and P doping modification combined with 3D porous *** as-obtained P-CNT/rGO aerogel cathode manifests significantly increased surface aera,expanded interlayer spacing,and enhanced pseudocapacitance behavior,thus leading to significantly enhanced specific capacitance and superb ions transport *** as-assembled ZHC based on P-CNT/rGO cathode delivers a superior energy density of 42.2 Wh/kg at an extreme-high power density of 80 kW/kg and excellent cycle ***-depth kinetic analyses are undertaken to prove the enhanced pseudocapacitance behavior and exceptional power output capability of ***,the reaction mechanism of physical and chemical adsorption/desorption of electrolyte ions on the P-CNT/rGO cathode is revealed by systematic ex-situ *** work can provide a valuable reference for developing advanced graphene-based cathode for high energy/power density ZHCs.

关键词： Graphene aerogel Phosphorus doping Pseudocapacitance Zinc-ion hybrid capacitors Energy storage mechanism

来源：评论

学校读者我要写书评

暂无评论

Enhanced thermoelectric and mechanical properties of Bi_(0.5)Sb_(1.5)Te_(3) alloy with dispersed yttrium oxide ceramic nanoparticles

引用

Rare Metals 2024年第4期43卷 1758-1768页

作者： Cun-Cheng Li Ming-Wei Zhang Ji-Wu Xin Lei Wei Wen-Yu Zhao School of Materials Science and Engineering Shandong University of TechnologyZibo255000China School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore639798Singapore State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan430070China

Reducing thermal conductivity while avoiding adverse interfacial reactions during sintering is crucial for improving the thermoelectric performance of Bi_(2)Te_(3)based *** ceramic nanoparticles are good candidates for achieving this *** this study,we designed and prepared a series of p-type Bi_(0.5)Sb_(1.5)Te_(3)nanocomposites decorated with Y_(2)O_(3)ceramic nanoparticles via ball-milling dispersion and spark-plasma *** to the chemical stability of the ceramics,no traces of atomic doping or interfacial reactions were *** measurements revealed that the Y_(2)O_(3)nanoparticles distributed along the grain boundaries acted as energy-dependent carrier-filtering centers to improve the scattering parameter and Seebeck coefficient,contributing to the elevated power factor even with a decreased electrical ***,the incorporated Y_(2)O_(3)nanoparticles and various defect structures they induced effectively strengthened the phonon scattering and suppressed the lattice thermal ***,a peak figure of merit(ZT)of 1.23 at 313 K was achieved for 0.4%Y_(2)O_(3)/Bi_(0.5)Sb_(1.5)Te_(3),which is 13%higher than that of the *** addition,the Vickers hardness of the composite material was 35%higher than that of the *** study demonstrates the effectiveness of ceramic nanoparticles in synergistic ally improving the thermoelectric and mechanical properties,which may be further extended to other thermoelectric systems.

关键词： Bi_(0.5)Sb_(1.5)Te_3 alloy Y_(2)O_(3) ceramic nanoparticles Microstructures Thermoelectric performance Mechanical properties

来源：评论

学校读者我要写书评

暂无评论

Biodegradable Mg alloy modified with bioactive exosomes for cardiovascular stent application

引用

Journal of Magnesium and Alloys 2024年第12期12卷 4988-5004页

作者： Ya-chen Hou Jing-an Li Chang Cao Chang Su Zhen Qin Ge Zhang Jia-cheng Guo Jun-nan Tang Jin-ying Zhang Shao-kang Guan Department of Cardiology The First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan 450052China Henan Province Key Laboratory of Cardiac Injury and Repair ZhengzhouHenan 450052China Henan Province Clinical Research Center for Cardiovascular Diseases ZhengzhouHenan 450018China School of Material Science and Engineering&Henan Key Laboratory of Advanced Magnesium Alloy&Key Laboratory of materials processing and mold technology(Ministry of Education) Zhengzhou University100 Science RoadZhengzhou 450001China

Cardiovascular stent has been widely applied to treat cardiovascular disease(CVD),which is the major disease contribution to mortality in the world *** magnesium(Mg)alloys are the encouraging materials in cardiovascular stents benefit from absorbability and ***,the ability of degradation is a double-edged sword for manufacture stent,modifying the surface to decrease the excessive degradation rate and promote the surface endothelialization could expand the prospect of the further *** this work,the biodegradable Mg-Zn-Y-Nd alloy was modified by MgF_(2)and dopamine polymer film(PDA)as the corrosion resistance layer and the bonding layer respectively,and then the exosome,a natural nanoparticle contains m RNAs and proteins,was tailored to give the surface better *** electrochemical test and weight loss test reflected the MgF_(2)-PDA/exosome coating increase the corrosion resistance of the Mg-Zn-Y-Nd *** cytocompatibility data indicated the novel MgF_2-PDA/exosome coating selectively reduced the tumor necrosis factor(TNF-α)expression and ROS release from macrophage,and promoted theα-SMA expression of smooth muscle *** addition,the MgF_(2)-PDA/exosome coating also improved the adhesion,proliferation,CD31 expression and nitric oxide(NO)release of vascular endothelial cells(ECs),all of which contribute to the surface *** the mechanism experiments showed the exosome released from the coating uptake by the ECs and assemble around the lysosome and mitochondria,and the released rate of the exosome on the coating is around 5 to 7 days,indicating excellent multi-functions of MgF_(2)-PDA/exosome coating in cardiovascular stent.

关键词： Mg-Zn-Y-Nd alloy Endothelialization Surface modification MgF_(2)-PDA/exosome coating

来源：评论

学校读者我要写书评

暂无评论

Realizing Highly Reversible Zinc Anode via Controlled-current Pre-deposition

引用

Energy & Environmental materials 2023年第6期6卷 327-334页

作者： Xinghang Chen Ming Li Qi Li Yuzhu Chen Buke Wu Meng Lin Qinyou An Liqiang Mai State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyHubeiWuhan 430070China Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong LaboratoryXianhu Hydrogen ValleyFoshan 528200China Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen 518055China SUSTech Energy Institute for Carbon Neutrality Southern University of Science and TechnologyShenzhen China Shenzhen Key Laboratory of Advanced Energy Storage Southern University of Science and TechnologyShenzhen 518055China

Aqueous zinc ion batteries have been considered as the prominent candidate in the next-generation batteries for its low cost,safety and high theoretical ***,formation of zinc dendrites and side reactions at the electrode/electrolyte interface during the zinc plating/stripping process affect the cycling reversibility of the zinc *** of the zinc plating/stripping process and realizing a highly reversible zinc anode is a great ***,we applied a simple and effective approach of controlled-current zinc pre-deposition at copper *** the current density of 40 mA cm^(-2),where the electron/ion transfers are both continuous and balanced,the Zn@CM-40 electrode with the(002)crystal plane orientation and the compactly aligned platelet morphology was successfully *** with the zinc foil,the Zn@CM-40 exhibits greatly enhanced reversibility in the repeated plating/stripping(850 h at 1 mA cm^(-2))for the symmetric battery test.A series of characterization techniques including electrochemical analyses,XRD,SEM and optical microscopy observation,were used to demonstrate the correlation between the structure of pre-deposited zinc layer and the cycling *** COSMOL Multiphysics modeling demonstrates a more uniform electric field distribution in the Zn@CM than the zinc foil due to the aligned platelet ***,the significant improvement is also achieved in a Zn||MnO_(2)full battery with a high capacity-retention(87%vs 47.8%).This study demonstrates that controlled-current electrodeposition represents an important strategy to regulate the crystal plane orientation and the morphology of the pre-deposited zinc layer,hence leading to the highly reversible and dendrite-free zinc anode for high-performance zinc ion batteries.

关键词： controlled-current pre-deposition dendrite-free reversible zinc anode zinc ion battery

来源：评论

学校读者我要写书评

暂无评论

Mitigating the dissolution of V_(2)O_(5) in aqueous ZnSO_(4) electrolyte through Ti-doping for zinc storage

引用

Chinese Chemical Letters 2024年第1期35卷 558-562页

作者： Zihe Wei Xuehua Wang Ting Zhu Ping Hu Liqiang Mai Liang Zhou Hubei Longzhong Laboratory Wuhan University of Technology(Xiangyang Demonstration Zone)Xiangyang 441000China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China School of Materials Science and Engineering Wuhan Institute of TechnologyWuhan 430205China Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory Xianhu Hydrogen ValleyFoshan 528200China

Aqueous zinc-ion batteries(AZIBs)have become a hotspot for electrochemical energy storage owing to the high safety,low cost,environmental friendliness,and favorable rate ***,the serious dissolution of cathode materials in aqueous electrolytes would lead to poor cyclability,which should be addressed before ***,we designed a Ti-doped V_(2)O_(5) with yolk-shell microspherical structure for *** Ti doping stabilizes the crystal structure and relieves the dissolution of V_(2)O_(5) in aqueous ZnSO_(4) *** optimized sample,Ti_(0.2)V_(1.8)O_(4.9),delivers a high capacity(355 mAh/g at 0.05 A/g)as well as good capacity retention(89%after 2500 cycles at 1.0 A/g).This work provides an effective strategy to mitigate the dissolution of cathode material in aqueous ZnSO_(4) electrolyte for cyclability enhancement.

关键词： Aqueous zinc-ion batteries V_(2)O_(5)cathode materials Aqueous ZnSO_(4)electrolyte Yolk-shell structure Ti doping

来源：评论

学校读者我要写书评

暂无评论

An Al–Al interpenetrating-phase composite by 3D printing and hot extrusion

引用

International Journal of Minerals,Metallurgy and materials 2023年第4期30卷 678-688页

作者： Yulin Lin Di Wang Chao Yang Weiwen Zhang Zhi Wang School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou 510640China Guangdong Key Laboratory for Processing and Forming of Advanced Metallic Materials South China University of TechnologyGuangzhou 510640China

We report a process route to fabricate an Al–Al interpenetrating-phase composite by combining the Al–Mg–Mn–Sc–Zr lattice structure and Al_(84)Ni_(7)Gd_(6)Co_(3)nanostructured structure. The lattice structure was produced by the selective laser melting and subsequently filled with the Al_(84)Ni_(7)Gd_(6)Co_(3)amorphous powder, and finally the mixture was used for hot extrusion to produce bulk samples. The results show that the composites achieve a high densification and good interface bonding due to the element diffusion and plastic deformation during hot *** bulk samples show a heterogeneous structure with a combination of honeycomb lattice structure with an average grain size of less than1 μm and nanostructured area with a high volume fraction of nanometric intermetallics and nanograin α-Al. The heterogeneous structure leads to a bimodal mechanical zone with hard area and soft area giving rise to high strength and acceptable plasticity, where the compressive yield strength and the compressive plasticity can reach ~745 MPa and ~30%, respectively. The high strength can be explained by the rule of mixture,the grain boundary strengthening, and the back stress, while the acceptable plasticity is mainly owing to the confinement effect of the nanostructured area retarding the brittle fracture behavior.

关键词： Al-based composites heterogeneous structure additive manufacturing mechanical properties

来源：评论

学校读者我要写书评

暂无评论

In Situ Reaction Strengthening and Toughening of B_(4)C/TiSi_(2)Ceramics

引用

Journal of Wuhan University of technology(materials Science) 2023年第1期38卷 12-19页

作者：夏涛涂晓诗张帆 ZHANG Jinyong REN Lin Hubei Longzhong Laboratory Wuhan University of TechnologyXiangyang Demonstration ZoneXiangyang 441000China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China School of Science Wuhan University of TechnologyWuhan 430070China

B_(4)C-SiC-TiB_(2)ceramics were prepared by in situ reactive hot-pressing sintering with TiSi_(2)as an *** reaction pathways of TiSi_(2)and B_(4)C were *** sintering was found to be a multistep *** reaction started at approximately 1000℃,and TiB_(2)was formed *** of Si and C started to react at 1300℃,and the unreacted Si melted at 1400℃to form a liquid ***_(2)predominantly affected the intermediate sintering process of B_(4)C and increased the sintering *** to the unique reaction process of TiSi_(2)and B_(4)C,a large number of aggregates composed of SiC and TiB_(2)were *** results showed that composite ceramics with the optimal flexural strength of 807 MPa,fracture toughness of 3.2 MPa·m1/2,and hardness of 32 GPa,were obtained when the TiSi_(2)content was 10 wt%.

关键词： in situ reaction hot pressing sintering TiSi_(2) B_(4)C composite ceramics reaction mechanism

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：