检索结果-内蒙古大学图书馆

Hierarchical N, S co-doped Fe3O4/C nanotubes constructed by ultrathin nanosheets for superior Li-ion batteries

Nano materials science 2024年

作者： Lyu, Fucong Zeng, Shanshan Sun, Ligang Ma, Fei-Xiang Yang, Shaoran Li, Zebiao Yao, Lu Hao, Fengqian Jia, Zhe Xiao, Xufen Li, Hongkun Wang, Aiwu Liu, Guo Yan, Yang Zhan, Yawen Li, Yang Yang Lu, Jian Centre for Advanced Structural Materials City University of Hong Kong Shenzhen Research Institute Greater Bay Joint Division Shenyang National Laboratory for Materials Science Shenzhen518057 China Hong Kong Branch of National Precious Metals Material Engineering Research Centre City University of Hong Kong 83 Tat Chee Avenue Kowloon Hong Kong Department of Material Science and Engineering City University of Hong Kong 83 Tat Chee Avenue Kowloon Hong Kong School of Science Harbin Institute of Technology Shenzhen518055 China School of Materials Science and Engineering Southeast University Nanjing211189 China Department of Mechanical Engineering City University of Hong Kong 83 Tat Chee Avenue Kowloon Hong Kong Shenzhen518045 China

In the present work, a facile strategy of synthesizing ultrathin nanosheets constructed N, S co-doped Fe3O4/C nanotubes via annealing the methyl orange-embedded Fe-glycerate nanotubes is reported. The nanosheet, constituting the wall of the nanotube, is formed by small Fe3O4 nanoparticles enchased highly graphitic carbon at a graphitization temperature as low as 450 °C. The nanosheets constructed N, S co-doped Fe3O4/C nanotubes exhibited superior electrochemical performance due to the highly accelerated intercalation/deintercalation rate of Li+ ions resulting from the homogeneous N and S dopants, greatly buffered volume expansion resulting from the abundant micro/meso-pores and hieratical nanosheet organized nanotube structure, and the good conductivity resulting from the graphitic carbon coating. Density functional theory (DFT) verified that N, S doping can efficiently promote the adsorption of Li+ ions thus accelerated the intercalation/deintercalation rate of Li+ ions. © 2024 Chongqing University

关键词： Nanosheets

来源：评论

学校读者我要写书评

暂无评论

Development of Lightweight and Flexible Carbon Nanofiber and Polyurethane Nanocomposite for EMI Shielding Applications

Development of Lightweight and Flexible Carbon Nanofiber and...

引用

Microwaves Antennas and Propagation Conference (MAPCON)

作者： Jitendra Tahalyani M. Jaleel Akhtar Kamal K. Kar Materials Science Programme Indian Institute of Technology Kanpur Kanpur India Department of Electrical Engineering MSP Indian Institute of Technology Kanpur Kanpur India Department of Mechanical Engineering MSP Indian Institute of Technology Kanpur Kanpur India

Future-generation EMI shielding requires thin, flexible, stretchable nanocomposite structures for conformal, flexible and bendable electronic appliances that can sustain harsh environmental conditions. The present work shows the design and development of such type structures by encapsulating carbon nanofiber (CNF) inside polyurethane (PU). The 8 wt% CNF (CNF8) shows improved conductivity and EMI shielding effectiveness (SE) in the X-band (8.2 to 12.4 GHz). The maximum total SE (SE T ) of 34.41 dB for CNF8 is observed at 0.75 mm thickness, unaffected by the complex environmental conditions like two hours of water sonication, 1000 mechanical bending cycles, and horizontal and vertical bending. The microstructure and electrical conductivity profile of these fabricated structures are used to explain the absorption dominating the EMI shielding process. Further, the layers of CNF8 are stacked together with the help of solvent followed by mechanical pressing, and the maximum SE T of 71.61 dB was achieved for a thickness of 2.21 mm. For a broadband EM shielding application, the SE T is calculated theoretically via simulation in CST microwave studio. The fabricated flexible, lightweight nanocomposite structures exhibit good EMI shielding and can be used in conformal surface coating and electronic packaging in defence, and aerospace applications.

关键词：

来源：评论

学校读者我要写书评

暂无评论

An Approximate Solution for the Stress Intensity Factor for a Cold Spray Repair to Metallic Structures with Multiple Co-Located Cracks

SSRN

引用

SSRN 2024年

作者： Peng, Daren Ang, Andrew Siao Ming Jones, Rhys Centre of Expertise in Structural Mechanics Department of Mechanical and Aeronautical Engineering Monash University Wellington Rd ClaytonVIC3800 Australia ARC Industrial Transformation Training Centre on Surface Engineering for Advanced Materials Faculty of Science Engineering and Technology Swinburne University of Technology John Street HawthornVIC3122 Australia

The paper provides an approximate analytical solution for the stress intensity factor (K) associated with a cold spray repair to a metallic specimen where the substrate contains an array of closely collocated small cracks. The solution uses the Westergaard stress function approach with undetermined coefficients. The relevant undetermined coefficients are determined by balancing the internal force and internal moment with the external force on the cracked section. The method proposed in this paper is simple and easy to use, and is in good agreement with solutions obtained using finite element analysis. © 2024, The Authors. All rights reserved.

关键词： Stress intensity factors

来源：评论

学校读者我要写书评

暂无评论

Ideal antiferroelectricity with large digital electrostrain in PbZrO3 epitaxial thin films

arXiv

引用

arXiv 2025年

作者： Si, Yangyang Fan, Ningbo Dong, Yongqi Ye, Zhen Deng, Shiqing Li, Yijie Zhou, Chao Zeng, Qibin You, Lu Zhu, Yimei Luo, Zhenlin Das, Sujit Bellaiche, Laurent Xu, Bin Liu, Huajun Chen, Zuhuang State Key Laboratory of Advanced Welding Joining of Materials and Structures School of Materials Science and Engineering Harbin Institute of Technology Shenzhen518055 China Jiangsu Key Laboratory of Thin Films School of Physical Science and Technology Soochow University Suzhou215006 China National Synchrotron Radiation Laboratory University of Science and Technology of China Anhui Hefei230026 China 2 Fusionopolis Way Innovis #08-03 Singapore138634 Singapore Department of Mechanical Engineering National University of Singapore 9 Engineering Drive 1 Singapore117575 Singapore Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology Beijing Beijing100083 China Condensed Matter Physics and Materials Science Department Brookhaven National Laboratory UptonNY11973 United States Materials Research Centre Indian Institute of Science Bangalore560012 India Physics Department Institute for Nanoscience and Engineering University of Arkansas FayettevilleAR72701 United States

Antiferroelectrics exhibit reversible antipolar-polar phase transitions under electric fields, yielding large electrostrain suitable for electromechanical devices. Nevertheless, in thin-film form, the antiferroelectric behavior is often obscured by competing ferroic orders, resulting in slanted hysteresis loops with undesired remnant polarization, subsequently posing challenges in obtaining ideal antiferroelectricity and understanding their intrinsic electrical behavior. Here, atomistic models for controllable antiferroelectric-ferroelectric phase transition pathways are unveiled along specific crystallographic directions. Guided by the anisotropic phase transition and orientation design, we achieved ideal antiferroelectricity with square double hysteresis loop, large saturated polarization (~60 μC/cm2), near-zero remnant polarization, fast response time (~75 ns), and near-fatigue-free performance (~1010 cycles) in (111)P-oriented PbZrO3 epitaxial thin films. Moreover, a bipolar and frequency-independent digital electrostrain (~0.83%) were demonstrated in this architype antiferroelectric system. In-situ X-ray diffraction studies further reveal that the large digital electrostrain results from intrinsic field-induced antiferroelectric-ferroelectric structural transition. This work demonstrates the anisotropic phase transition mechanism and ideal antiferroelectricity with large digital electrostrain in antiferroelectric thin films, offering a new avenue for applications of antiferroelectricity in nanoelectromechanical systems. Copyright © 2025, The Authors. All rights reserved.

关键词： Antiferroelectric materials

来源：评论

学校读者我要写书评

暂无评论

Editorial: Optimal design and efficiency improvement of fluid machinery and systems: volume III

引用

Frontiers in Energy Research 2025年 13卷

作者： Yang, Yang Ji, Leilei Agarwal, Ramesh K. Kan, Kan Tao, Ran Presas, Alexandre College of Hydraulic Science and Engineering Yangzhou University Yangzhou China Key Laboratory of Fluid and Power Machinery Ministry of Education Sichuan Chengdu China National Research Center of Pumps Jiangsu University Zhenjiang China Department of Mechanical Engineering and Materials Science Washington University in St. Louis St. LouisMO United States College of Energy and Electrical Engineering Hohai University Nanjing China College of Water Resources and Civil Engineering China Agricultural University Beijing China Barcelona Spain

Fluid machinery plays a pivotal role in energy and industrial systems, where performance, efficiency, and reliability drive technological advancements. The complexity of fluid dynamics, coupled with increasing demands for sustainability and efficiency, underscores the need for innovative research to tackle design and operational challenges. This special issue, Optimal Design and Efficiency Improvement of Fluid Machinery and Systems: Volume III, features six cutting-edge studies that address these challenges through two key themes: performance optimization and efficiency enhancement, and the analysis of flow dynamics and operational *** operation is essential for enhancing the performance and reliability of fluid machinery, particularly in hydraulic and hydrogen-based systems. Optimizing volumetric efficiency, minimizing leakage, and validating performance parameters through rigorous testing are pivotal to achieving these goals. This section synthesizes findings from three studies, offering significant insights into the advancement of fluid machinery *** et al. [1] explored the efficiency performance of a large vertical submersible mixed-flow pump using model and prototype tests, reporting a maximum efficiency of 77.8% and a conversion efficiency of 80.33%, respectively. The study underscored the complementary roles of these testing methods, demonstrating that prototype tests provide critical validation under diverse operating conditions. Similarly, Zhai et al. [2,3] investigated the leakage characteristics and volumetric efficiency of hydrogen circulation pumps (HCPs) employed in fuel cell systems. By introducing a refined leakage flow calculation formula, the authors reduced the average error to 3.82%, significantly improving prediction accuracy compared to traditional methods. Understanding flow dynamics is crucial for ensuring the stability, efficiency, and operational flexibility of fluid systems. By investigating pressure pulsati

关键词： fluid machinery and system optimal design efficiency improvement pressure pulsation dynamics computational fluid dynamics

来源：评论

学校读者我要写书评

暂无评论

Protected valley states and generation of valley- and spin-polarized current in monolayer MA2Z4

引用

Physical Review B 2022年第19期105卷 195151-195151页

作者： Jiaren Yuan Qingyuan Wei Minglei Sun Xiaohong Yan Yongqing Cai Lei Shen (沈雷) Udo Schwingenschlögl School of Physics and Electronic Engineering and School of Material Science and Engineering Jiangsu University Zhenjiang 212013 China Physical Science and Engineering Division King Abdullah University of Science and Technology Thuwal 23955-6900 Saudi Arabia Joint Key Laboratory of the Ministry of Education Institute of Applied Physics and Materials Engineering University of Macau Macau 999078 China Department of Mechanical Engineering and Engineering Science National University of Singapore 9 Engineering Drive 1 Singapore 117542

The optical selection rules obeyed by two-dimensional materials with spin-valley coupling enable the selective excitation of carriers. We show that several members of the monolayer MA2Z4 (M=Mo and W;A=C, Si, and Ge; Z=N, P, and As) family are direct band-gap semiconductors with protected valley states and that circularly polarized infrared light can induce valley-selective interband transitions. Therefore, they are able to generate a close to 100% valley- and spin-polarized current under an in-plane bias and circularly polarized infrared light, which can be exploited to encode, process, and store information.

关键词： Valleytronics 2-dimensional systems Density functional theory

来源：评论

学校读者我要写书评

暂无评论

High-throughput calculations of antiferromagnets hosting anomalous transport phenomena

引用

Physical Review B 2024年第9期109卷 094435-094435页

作者： Takuya Nomoto Susumu Minami Yuki Yanagi Michi-To Suzuki Takashi Koretsune Ryotaro Arita Research Center for Advanced Science and Technology University of Tokyo Komaba 153-8904 Japan Department of Mechanical Engineering and Science Kyoto University Kyoto 615-8540 Japan Liberal Arts and Sciences Toyama Prefectural University Toyama 939-0398 Japan Center for Computational Materials Science Institute for Materials Research Tohoku University Sendai 980-8577 Japan Center for Spintronics Research Network Graduate School of Engineering Science Osaka University Toyonaka Osaka 560-8531 Japan Department of Physics Tohoku University Sendai 980-8578 Japan Center for Emergent Matter Science RIKEN Wako 351-0198 Japan

We develop a high-throughput computational scheme based on cluster multipole theory to identify new functional antiferromagnets (AFMs). This approach is applied to 228 magnetic compounds listed in the AtomWork-Adv database, known for their elevated Néel temperatures. We conduct systematic investigations of both stable and metastable magnetic configurations of these materials. Our findings reveal that 34 of these compounds exhibit AFM structures with zero propagation vectors and magnetic symmetries identical to conventional ferromagnets, rendering them potentially invaluable for spintronics applications. By cross-referencing our predictions with the existing MAGNDATA database and published literature, we verify the reliability of our findings for 26 out of 28 compounds with partially or fully elucidated magnetic structures in the experiments. These results not only affirm the reliability of our scheme but also point to its potential for broader applicability in the ongoing quest for the discovery of functional magnets.

关键词： First-principles calculations Magnetic texture Spintronics Antiferromagnets Noncollinear magnets

来源：评论

学校读者我要写书评

暂无评论

Structural properties of full-scope AlN/BN compounds investigated using ab initio calculations

引用

Procedia Structural Integrity 2024年 54卷 453-459页

作者： Jelena Zagorac Matej Fonovic Milos B. Djukic Svetlana Butulija Tatiana Prikhna Dejan Zagorac Materials Science Laboratory Institute of Nuclear Sciences „Vinča” University of Belgrade Belgrade Serbia Center for synthesis processing and characterization of materials for application in extreme conditions “CextremeLab” Belgrade Serbia Faculty of Engineering University of Rijeka—RiTeh Rijeka Croatia University of Belgrade Faculty of Mechanical Engineering Belgrade Serbia Department no. 7 – Promising Technologies of Superhigh Pressures Dispersed Materials and Sintering of Ceramics V. Bakul Institute for Superhard Materials of the National Academy of Sciences of Ukraine (NASU) Kiev Ukraine

In the last few decades, aluminum nitride (AlN) and boron nitride (BN) have become a point of interest to many researchers and scholars from different disciplines around the world. Due to its attractive properties, AlN has been successfully used in various applications, starting from advanced ceramics materials, additive for grain size control in micro-alloyed steels, through optoelectronics and microelectronics, and finally to semiconductors. On the other hand, BN has broad applications in various fields, such as 2D material, lubricant material, superhard and semiconductor material as well as many others. This study focuses on the mixed AlN/BN compounds, in particular, boron-rich AlN and aluminum-rich BN systems, thus having the entire range of AlN/BN compositions. The special focus was on structural properties investigated using the hybrid B3LYP method. Important structural properties were investigated to offer novel technological and industrial applications of mixed AlN/BN materials.

关键词： AlN/BN Aluminium nitride B3LYP Boron nitride

来源：评论

学校读者我要写书评

暂无评论

Thermal-Protective and Oxygen-Resistant Nanocoating Using Silica-Nanocomposites for Laser Thinning of Polymorphic Molybdenum Ditellurides

SSRN

引用

SSRN 2023年

作者： Heo, Soyoung Kim, Seulbi Lee, Seung Yeon Yang, Heejun Park, Ji Hun Cho, Suyeon Division of Chemical Engineering and Materials Science Graduate Program in System Health Science and Engineering Ewha Womans University Seoul03760 Korea Republic of Department of Science Education Ewha Womans University Seoul03760 Korea Republic of Daejeon34141 Korea Republic of

Laser irradiation has been investigated as a method of fabricating atomically-thin crystals from layered two-dimensional (2D) materials with precise thickness control. However, during laser irradiation, inevitable structural changes can occur in the 2D materials due to the high thermal energy, altering their physical and chemical properties and introducing disorder, which has hindered the study and use of the intrinsic properties of atomically-thin materials. In this study, we report a laser thinning method using a new coating material, a layered silica-based nanocomposite (SNC), that preserves the pristine crystal structure of a polymorphic 2D material, MoTe2, down to an atomically thin geometry. The nano-porous coating of layered silica-based nanocomposite (SNC) was robust against thermal heating and behaved as a good thermal-protective and oxygen-resistant material in the laser thinning process. Therefore, the SNC-coated MoTe2 flakes were successfully thinned down to atomically-thin geometry, while preserving their 2H structure. Accordingly, our SNC coating of 2D materials is a promising way to engineer the phase and geometry of polymorphic 2D materials, enabling versatile applications in various optoelectronic, spintronic, and electronic devices. © 2023, The Authors. All rights reserved.

关键词： Coatings

来源：评论

学校读者我要写书评

暂无评论

Advanced Characterization of Natural Fiber Composites Using Digital Image Correlation

Research Square

引用

Research Square 2025年

作者： Deepthi, K. Sudha Tandel, Kartik S. Patange, Siva Subba Rao Rammohan, B. Babu, Kamal P. Kumar, Nikhil C. Department of Mechanical Engineering Dayananda Sagar University Harohalli Karnataka Bangalore562 112 India Department of Aerospace Engineering Dayananda Sagar University Harohalli Karnataka Bangalore562 112 India Structural Technologies Division CSIR-National Aerospace Laboratories Karnataka Bangalore560017 India School of Computer Science and Engineering RV University Mysuru Road Karnataka Bangalore560059 India Department of Mechanical Engineering Dayananda Sagar University Harohalli Karnataka Bangalore562112 India Materials Science Division CSIR-National Aerospace Laboratories Karnataka Bangalore560017 India

Composites made from natural fibers have drawn much interest because of their sustainability, lightweight qualities, and capacity to replace synthetic materials in a variety of engineering applications. Nevertheless, their mechanical behavior is still complicated, and precise performance assessment calls for sophisticated characterization methods. This work presents unique approaches to full-field strain and displacement. investigation of natural fiber composites mechanically employing Digital Image Correlation (DIC), a non-contact optical measurement method. The study’s use of DIC allows for the accurate capture of deformation patterns under various loading scenarios, facilitating a thorough knowledge of the fiber-matrix interactions, failure causes, and structural integrity of the composite. The experimental results are evaluated against standard methods, revealing that DIC allows a more complete and accurate evaluation of natural fiber composites’ mechanical properties. This work contributes to the wider use of natural fiber composites in sectors such as construction, automotive, and aerospace by highlighting the potential of digital image correlation (DIC) to improve material testing precision and by suggesting new approaches for optimizing natural fiber composite design. © 2025, CC BY.

关键词： Tensile testing

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：