检索结果-内蒙古大学图书馆

The photocatalytic properties of hollow (GaN)1-x(ZnO)x composite nanofibers synthesized by electrospinning

Applied Surface Science 2017年 396卷 888-896页

作者： Wang, Ding Zhang, Minglu Zhuang, Huaijuan Chen, Xu Wang, Xianying Zheng, Xuejun Yang, Junhe College of Materials Science and Engineering University of Shanghai for Science & Technology Shanghai200093 China School of Mechanical Engineering Xiangtan University Xiangtan411105 China Key Laboratory of Welding Robot and Application Technology of Hunan Province Xiangtan University Xiangtan411105 China

(GaN)1-x(ZnO)x composite nanofibers with hollow structure were prepared by initial electrospinning, and the subsequent calcination and nitridation. The structure and morphology characteristics of samples were investigated by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDS) and transmission electron microscopy (TEM). The characterization results showed the phase transition from ZnGa2O4 to (GaN)1-x(ZnO)x solid-solution under ammonia atmosphere. The preparation conditions were explored and the optimum nitridation temperature and holding time are 750 °C and 2 h, respectively. The photocatalytic properties of (GaN)1-x(ZnO)x with different Ga:Zn atomic ratios were investigated by degrading Rhodamine B under the visible light irradiation. The photocatalytic activity sequence is (GaN)1−x(ZnO)x (Ga:Zn = 1:2) > (GaN)1−x(ZnO)x (Ga:Zn = 1:3) > ZnO nanofibers > (GaN)1−x(ZnO)x (Ga:Zn = 1:4) > (GaN)1−x(ZnO)x (Ga:Zn = 1:1). The photocatalytic mechanism of the (GaN)1−x(ZnO)x hollow nanofibers was further studied by UV–vis diffuse reflectance spectra. The excellent photocatalytic performance of (GaN)1−x(ZnO)x hollow nanofibers was attributed to the narrow band gap and high surface area of porous nanofibers with hollow structure. © 2016

关键词： Zinc oxide

来源：评论

学校读者我要写书评

暂无评论

用于钎焊C/C复合材料的稀土改性还原氧化石墨烯增强AgCuTi复合钎料

引用

Journal of Central South University 2024年第5期31卷 1398-1411页

作者：吴靓李月陈锦微张汭张乾坤肖逸锋 School of Mechanical Engineering and Mechanics Xiangtan UniversityXiangtan 411105China Key Laboratory of Welding Robot and Application Technology of Hunan Province Xiangtan 411105China Welding Automation Equipment Engineering Research Center of Hunan Province Xiangtan 411105China

为了解决钎焊接头中脆性化合物的形成问题,我们设计了一种创新性的稀土改性还原氧化石墨烯增强AgCuTi复合钎料,进而获得了以Ag-Cu共晶为主要组织且脆性化合物生成量合适的钎焊接头。对比分析了有无稀土Ce改性的复合钎料的成分和显微组织... 详细信息

为了解决钎焊接头中脆性化合物的形成问题,我们设计了一种创新性的稀土改性还原氧化石墨烯增强AgCuTi复合钎料,进而获得了以Ag-Cu共晶为主要组织且脆性化合物生成量合适的钎焊接头。对比分析了有无稀土Ce改性的复合钎料的成分和显微组织,结果表明,经Ce改性后的还原氧化石墨烯在钎料中更加均匀分散。比较了分别采用有无Ce改性的钎料钎焊C/C复合材料-C/C复合材料接头的界面微观结构,并研究了石墨烯含量对接头组织和性能的影响。结果表明,由于经Ce改性的钎料中的还原氧化石墨烯分散性更好,从而细化了焊缝组织,且物相分布更均匀,使得接头的剪切强度明显提高。当石墨烯含量为0.5 wt.%时,使用Ce改性的钎料所得钎焊接头的平均剪切强度最高,为31.82 MPa,提高了50%。

关键词：稀土改性还原氧化石墨烯复合钎料 C/C复合材料钎焊

来源：评论

学校读者我要写书评

暂无评论

An analytical solution of the subsequent drawing force on multistage deep drawing of cylindrical cup 14th

An analytical solution of the subsequent drawing force on mu...

引用

14th Asia-Pacific Symposium on Engineering Plasticity and its applications, AEPA 2018

作者： Lin, Qiquan Wang, Zhenzhu Peng, Yanrong Hu, Chengwu Dong, Wenzheng Wang, Yingle Key Laboratory of Robot and Application Technology of Hunan Province Xiangtan University Hunan Xiangtan411105 China School of Mechanical Engineering Hunan University of Technology Hunan Zhuzhou412007 China

ISBN: (纸本)9783035713626

In multistage deep drawing process, the subsequent drawing force(SDF) is a key reference value, which plays a significant role on the practical die structure design. In the present study, an analytical calculation of the radial stress at the die exit as well as the SDF in cylindrical cup drawing process are proposed, considering the previous strain hardening in the first drawing, normal anisotropy, frictional coefficient and die arc radius. As a result, the calculated maximum subsequent drawing force (MSDF) is in good agreement with the experimental result. Besides, the MSDF decreases as normal anisotropy value increases, while increases as frictional coefficient and strain hardening exponent increases respectively. © 2019 Trans Tech Publications Ltd, Switzerland.

关键词： Strain hardening

来源：评论

学校读者我要写书评

暂无评论

Effects of Mg content on pore structure and electrochemical corrosion behaviors of porous Al-Mg alloys

引用

Journal of Central South University 2016年第10期23卷 2483-2491页

作者： He, Wen-yuan Xiao, Yi-feng Wu, Liang Xu, Yan-fei Qian, Jin-wen He, Yue-hui Zheng, Xue-jun School of Mechanical Engineering Xiangtan University Xiangtan411105 China Key Laboratory of Welding Robot and Application Technology of Hunan Province Xiangtan University Xiangtan411105 China Engineering Research Center of Complex Trajectory Processing Technology and Equipment of Ministry of Education Xiangtan University Xiangtan411105 China State Key Laboratory of Powder Metallurgy Central South University Changsha410083 China

Porous Al-Mg alloys with different nominal compositions were successfully fabricated via elemental powder reactive synthesis, and the phase composition, pore structure, and corrosion resistance were characterized with X-ray diffractometer, scanning electron microscope and electrochemical analyzer. The volume expansion ratio, open porosity and corrosion resistance in 3.5% (mass fraction) NaCl aqueous solution of the alloys increase at first and then decrease with the increase of Mg content. The maxima of volume expansion ratio and open porosity are 18.3% and 28.1% for the porous Al-56%Mg (mass fraction) alloy, while there is the best corrosion resistance for the porous Al-37.5% Mg (mass fraction) alloy. The pore formation mechanism can be explained by Kirkendall effect, and the corrosion resistance can be mainly affected by the phase composition for the porous Al-Mg alloys. They would be of the potential application for filtration in the chloride environment. © 2016, Central South University Press and Springer-Verlag Berlin Heidelberg.

关键词： Aluminum alloys

来源：评论

学校读者我要写书评

暂无评论

Constitutive Model and Plate Forging Ability of 5052 Aluminum Alloy Under Different Temperatures 13th

Constitutive Model and Plate Forging Ability of 5052 Aluminu...

引用

13th International Conference on the technology of Plasticity, ICTP 2021

作者： Li, Yantao Dong, Wenzheng Lin, Qiquan Wang, Zhigang Key Laboratory of Robot and Application Technology of Hunan Province Xiangtan University Xiangtan China State Key Laboratory of Materials Processing and Die and Mould Technology Huazhong University of Science and Technology Wuhan China Department of Mechanical and System Engineering Gifu University Gifu Japan

ISBN: (纸本)9783030753801

The hot tensile deformation behavior of 5052 aluminum alloy is investigated by uniaxial tensile tests with the temperature range of 523–723 K and strain rate range of 0.001–0.1 s−1. The constitutive equation is established based on the Arrhenius-type equation and Zener–Hollomon parameters, which are applied to numerical simulation for solid boss forming by plate forging process. As a result, the flow stresses obtained from the constitutive equation are consistent with the experiments, and the proposed constitutive equation is succeeded to predict the deformation behavior in the plate forging process. The best forming temperature for boss solid forming is 673 K based on the boss forming ability analysis. © 2021, The Minerals, Metals & Materials Society.

关键词： Constitutive equations

来源：评论

学校读者我要写书评

暂无评论

One-step solid-phase synthesis of binder-free molybdenum disulfide/carbon fibers paper anode for high-performance lithium-ion batteries

引用

Journal of Alloys and Compounds 2018年 768卷 33-41页

作者： Wenyuan He Xuejun Zheng Jinfeng Peng Qiang Zhang Dazhao Pei Xinyang Yan School of Mechanical Engineering Xiangtan University Xiangtan 411105 China Engineering Research Center of Complex Tracks Processing Technology and Equipment of Ministry of Education Xiangtan University Xiangtan 411105 China Key Laboratory of Welding Robot and Application Technology of Hunan Province Xiangtan University Xiangtan 411105 China

A facile one-step solid-phase synthesis strategy is developed for synthesizing a binder-free molybdenum disulfide/carbon fibers paper (MoS 2 /CFP) anode. The microstructure, composition, morphology and electrochemical performances were investigated. It is found that the thin MoS 2 layers are well anchored on the interlaced carbon fibers to form MoS 2 /CFP, which has mesoporous structure and large specific surface area of ∼18.8 m 2 g -1 . As a result, the obtained MoS 2 /CFP anode exhibits a reversible capacity of 261 mAh·g −1 with 31.2% loading ratio of MoS 2 . After subtracting the capacity of CFP, the MoS 2 in the composite anode delivers a reversible capacity of 539 mAh·g −1 and shows better cycle stability than commercial MoS 2 after 100 cycles at 100 mA g −1 . The remarkable electrochemical performances could be attributed to the buffer space among carbon fibers for the volume changes of MoS 2 as well as the highly conductive carbon fibers network, suggesting that the MoS 2 /CFP is a promising binder-free anode for lithium-ion batteries.

关键词： One-step solid-phase synthesis Binder-free Molybdenum disulfide Carbon fibers paper Lithium-ion battery

来源：评论

学校读者我要写书评

暂无评论

Effect of Foam Interlayer Thickness and Pore Size on the Microstructure and Properties of Brazed Joints

SSRN

引用

SSRN 2024年

作者： Xiao, Yifeng Song, Zhang Zhang, Rui Bai, Shijie Wu, Liang School of Mechanical Engineering Xiangtan University Xiangtan China Engineering Research Center of Complex Tracks Processing Technology and Equipment of Ministry of Education Xiangtan University Xiangtan China Key Laboratory of Welding Robot and Application Technology of Hunan Province Xiangtan University Xiangtan China Hunan Provincial Engineering and Technology Research Center for Nickel-based Welding Consumables Xiangtan China

This study investigates the effects of the interlayer thickness and pore size of foam metal materials on the microstructure and properties of dissimilar material brazed joints. Using finite element simulation calculations, the mechanism by which the foam interlayer alleviates residual stress is elucidated. C/C composite materials and TC4 alloy were used as the base materials for brazing, with a foam Ni interlayer and AgCuTi foil as the brazing filler to achieve high-quality joining of the C/C composite and TC4 alloy. The brazed interface microstructure with a 0.4 mm thick foam Ni interlayer with a pore size of 0.5 mm was more uniform, and the shear strength of the joint reached 21.23 MPa, representing an 85.96% increase compared to the joint without the foam Ni interlayer. Finite element analysis indicated that the residual stress of the brazed joint with the foam Ni interlayer was 22% lower than that of the joint without the interlayer. © 2024, The Authors. All rights reserved.

关键词： Brazing

来源：评论

学校读者我要写书评

暂无评论

Effect of Foam Interlayer Thickness and Pore Size on the Microstructure and Properties of Brazed Joints

SSRN

引用

SSRN 2024年

作者： Xiao, Yifeng Song, Zhang Zhang, Rui Zhang, Qiankun Bai, Shijie Wu, Liang School of Mechanical Engineering and Mechanics Xiangtan University Xiangtan China Engineering Research Center of Complex Tracks Processing Technology and Equipment Ministry of Education Xiangtan University Xiangtan China Key Laboratory of Welding Robot and Application Technology of Hunan Province Xiangtan University Xiangtan China Hunan Provincial Engineering and Technology Research Center for Nickel-based Welding Consumables Xiangtan China

关键词： Brazing

来源：评论

学校读者我要写书评

暂无评论

Recovery of cycling-induced endurance failed HfO_x based memristive devices by utilizing oxygen plasma treatment

引用

Applied Physics Letters 2019年第24期115卷 243105-243105页

作者： Wang, Dong Yan, Shaoan Chen, Qilai He, Qiming Li, Gang Xiao, Yongguang Tang, Minghua Zheng, Xuejun School of Mechanical Engineering Xiangtan University Xiangtan Hunan 411105 China Key Laboratory of Welding Robot and Application Technology of Hunan Province School of Mechanical Engineering Xiangtan University Xiangtan Hunan 411105 China Key Laboratory of Microelectronics Devices and Integration Technology Institute of Microelectronics Chinese Academy of Sciences Beijing 100029 China School of Materials Science and Engineering Xiangtan University Xiangtan Hunan 411105 China

The oxygen ion (O2-) loss effect during resistive switching (RS) cycles will inevitably lead to endurance degradation or even failure in oxide-based memristive devices. In this Letter, we propose an effective way to r...

The oxygen ion (O^2-) loss effect during resistive switching (RS) cycles will inevitably lead to endurance degradation or even failure in oxide-based memristive devices. In this Letter, we propose an effective way to recover the cycling-induced endurance failed HfO_x based memristive devices by utilizing oxygen plasma treatment (OPT). In the as-fabricated Pt/HfO_x/Pt devices, a negative SET event is observed after consecutive normal RS cycles and eventually triggers endurance failure. The appearance of the intermediate resistance state at the initial stage of the negative SET cycle indicates a prominent reduction of the migration barrier of O^2-, which accounts for the occurrence of negative SET after increasing cycles. Then, we recover the devices from endurance failure by moderate OPT, which can supply the available O^2- in RS cycles. More importantly, the first recovered devices after endurance failure can be recovered again through OPT, which better proves the validity of the recovery method. This study could provide an effective approach for understanding and addressing the cycling-induced endurance failure issue in oxide-based memristive devices. © 2019 Author(s).

关键词：

来源：评论

学校读者我要写书评

暂无评论

The Viscosity Measurement of Ti15Zr60Hf20Si5 and its Calculation

SSRN

引用

SSRN 2024年

作者： Huang, Jiajia Wu, Liang Li, Xi Zeng, Yi Chen, Jinwei Xiao, Yifeng Zhang, Qiankun State Key Laboratory of Powder Metallurgy Central South University Changsha410083 China School of Mechanical Engineering and Mechanics Xiangtan University Xiangtan411105 China Key Laboratory of Welding Robot and Application Technology of Hunan Province Xiangtan University Xiangtan411105 China School of Physics and Electronic Sciences Changsha University of Science and Technology Changsha410114 China Hunan Provincial Key Laboratory of Flexible Electronic Materials Genome Engineering Changsha University of Science and Technology Changsha410114 China

The study of the viscosity of Ti-Zr-Hf-Si alloy is of great help to prepare UHTCMCs. In this work, the viscosity of Ti15Zr60Hf20Si5 is 11.8 m·Pa·s by the drop oscillation method under electrostatic levitation conditions at 2273 K. For qualitative assessment of the samples, it was found that Ti15Zr60Hf20Si5 does not contain solid phase at 2273 K using experimental analysis (SEM, EPMA, XRD, and TEM). Based on the experimental results, the viscosity database of the pure liquid phase for Ti-Zr-Hf-Si quaternary systems was constructed by the viscosity model in our previous work. © 2024, The Authors. All rights reserved.

关键词： Viscosity

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：