检索结果-内蒙古大学图书馆

Improved high temperature stability and enhanced high-speed dry cutting performance of AlCrBN coatings by alloying with B

引用

International Journal of Refractory Metals and Hard Materials 2025年 131卷

作者： Tao, Langlang Wang, Jianming Fang, Wei Cai, Fei Xu, Dongliang Zhang, Shihong Key Laboratory of Green Fabrication and Surface Technology of Advanced Metal Materials Ministry of Education Anhui University of Technology Anhui Province Anhui Maanshan City243000 China School of Materials Science and Engineering Anhui University of Technology Anhui Province Maanshan City243002 China School of Mechanical and Automotive Engineering Anhui Water Conservancy Technical College Anhui Province China

Boron (B)-containing AlCrBN coatings are promising protective coatings for high-speed dry cutting application. In this work, AlCrBN coatings with various B contents (0 at.%, 2.9 at.%, and 4.8 at.% namely B0, B1, and B2) were synthesized, and their high-temperature and high-speed dry cutting performance were evaluated by the high-temperature vacuum annealing and high-speed dry cutting experiment. Comparing with B0 coating (AlCrN coating without B), B1 and B2 coatings delayed/suppressed the phase decomposition from fcc-(AlCr)N into h-AlN and Cr2N, and also suppressed the diffusion of Co from the substrate into the coating surface at an annealing temperature of 1000 °C. This also contributed to the high annealed hardness of 3400 HK0.05 at 1000 °C for B1 and B2 coatings. High-speed dry turning result showed that B1 coated insert exhibited a longer cutting time (13 min), required less cutting force, and had a lower coefficient of friction during the whole cutting process. The wear mechanisms are abrasive, adhesive, and oxidative on both rake faces and flank faces for all coated inserts, however, addition of B reduced its wear of a B1-coated insert. TEM results from the worn rake face of a B1-coated insert revealed that an oxide tribo-film composed of w-AlN and Al2O3 emerged upon the unaffected AlCrBN coating, further confirming the structural stability of the AlCrBN coating under high-speed dry cutting. © 2025

关键词： Aluminum coatings

来源：评论

学校读者我要写书评

暂无评论

Direct Evidence of the Relationship between Piezoelectricity and Catalytic Activity

SSRN

引用

SSRN 2025年

作者： Gao, Wenpeng Zheng, Huashan Luo, Huajie Zhang, Haibo Jo, Wook Xie, Bing School of Power and Energy Jiangxi Key Laboratory of Green General Aviation Power Nanchang Hangkong University Nanchang330063 China Functional Materials and Acousto-optic Instruments Institute School of Instrumentation Science and Engineering Harbin Institute of Technology Harbin150080 China School of Materials Science and Engineering University of Science and Technology Beijing Beijing100083 China School of Materials Science and Engineering Huazhong University of Science and Technology Wuhan430074 China Ulsan44919 Korea Republic of Beijing Advanced Innovation Center for Materials Genome Engineering China State Key Laboratory of Material Processing and Die & Mould Technology China School of Materials Science and Engineering

Piezocatalysis is highly valued for its efficient energy conversion and environmental capabilities. However, the fundamental connection between piezoelectricity and piezocatalytic activity remains to be thoroughly investigated. Herein, piezoceramic thin flakes with varying levels of piezoelectricity were examined to quantitatively assess the impact of the piezoelectric coefficient (d33) on the piezocatalytic activation in energy and environment applications. The piezoceramic flake, 220 μm thick, possessing the highest piezoelectricity (d33 = 1100 pC/N), demonstrated the highest H2O2 yield (572 μM h-1) and the fastest degradation rate (k = 0.0725 min-1) of Rhodamine B (RhB), exceeding the best performance of previously reported ceramic blocks. In contrast, the same thickness flake with the lowest piezoelectricity (d33 = 150 pC/N) exhibited the weakest piezocatalytic performance. By analyzing internal carrier characteristics and simulating carrier migration pathways under an electric field, a quantitative relationship between piezoelectricity and piezocatalytic activity was established. The piezoceramic flake with higher piezoelectricity demonstrated a higher effective free carrier concentration, a larger number of transiently migrating carriers, and a shorter migration distance due to a stronger built-in electric field, resulting in enhanced piezocatalytic activity. This work clearly elucidates the relationship between piezoelectricity and piezocatalytic activity. © 2025, The Authors. All rights reserved.

关键词： Piezoelectricity

来源：评论

学校读者我要写书评

暂无评论

Creating Sodium Ion Channels via De Novo Encapsulation of Ionophores for Enhanced Water Energy Harvesting

引用

advanced Materials 2025年第0期 e2420636页

作者： Guo, Qing Xing, Zhiwei Guo, Huaxi Lai, Zhuozhi Yi, Jiaming Wu, Di Dai, Zhifeng Zhang, Li Wang, Sai Ma, Shengqian Q., Sun Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology College of Chemical and Biological Engineering Zhejiang University Hangzhou310027 China Key Laboratory of Surface & Interface Science of Polymer Materials of Zhejiang Province School of Chemistry and Chemical Engineering Zhejiang Sci-Tech University Hangzhou310018 China Hangzhou Institute of Advanced Studies Zhejiang Normal University Hangzhou311231 China Department of Chemistry University of North Texas 1508 W Mulberry St DentonTX76201 United States

Biological ion channels achieve remarkable permselectivity and cation discrimination through the synergy of their intricate architectures and specialized ionophores within confined nanospaces, enabling efficient energy conversion. Emulating such selectivity in synthetic nanochannels, however, remains a persistent challenge. To address this, a novel host-guest assembly membrane is developed by incorporating sodium-selective ionophores into a β-ketoenamine-linked covalent organic framework (COF). This design confers exceptional permselectivity and Na+ selectivity, achieving Na+/K+ and Na+/Li+ selectivity ratios of 3.6 and 103, respectively, along with near-perfect Na+/Cl− selectivity under a 0.5 M || 0.01 M salinity gradient. Notably, the membrane dynamically switches its permselectivity to favor anion transport in the presence of high-valent cations (e.g., Ca2+), overcoming limitations such as uphill cation diffusion and back currents observed in conventional cation-selective membranes. This adaptive behavior yields a 4.6-fold increase in output power density in Ca2+-rich environments. These findings advance the design of biomimetic nanochannels with unparalleled ion selectivity and enhanced energy conversion efficiency. © 2025 Wiley-VCH GmbH.

关键词： Ionophores

来源：评论

学校读者我要写书评

暂无评论

Room-Temperature Perovskite Ferromagnetic Insulator via Three-Dimensional Tensile Strain

引用

Physical Review Letters 2025年第1期134卷 016702-016702页

作者： Tianyu Li Yali Yang Shiqing Deng Fangyuan Zhu Tianfu Zhang Yu Chen Huanhua Wang Feixiang Long Xiaolong Li Department of Physical Chemistry University of Science and Technology Beijing Beijing 100083 China Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology Beijing Beijing 100083 China School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China School of Mathematics and Physics University of Science and Technology Beijing Beijing 100083 China State Key Laboratory of Surface Physics and Department of Physics Fudan University Shanghai 200433 China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai 201204 China Beijing Synchrotron Radiation Facility Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

Ferromagnetic insulators are receiving ever-increasing research activities driven not only by the unique advantage of low power loss during spin-wave-based information processing but also by the potential to construct next-generation spintronic devices. However, either the exceedingly rare candidates or the low Curie temperature far below room temperature greatly hinder their practical application. Here, through the modulation of a novel three-dimensional (3D) tensile strain, a room-temperature ferromagnetic insulating state with a Curie temperature as high as 594 K is achieved in self-assembled LaCoO3:MgO nanocomposite thin films. Atomically resolved electron microscopy quantifications identify the 3D strain state of the thin film, where the +2.6% out-of-plane and +2.1% in-plane tensile strains are attributed to the interphase mismatch between the LaCoO3 and MgO building blocks and epitaxial constraint, respectively. Combined with the assessment of electronic states and theoretical analysis, we correlate the strain state with the resulting ferromagnetic insulating property and clarify the underlying mechanisms, by which the emergent strain states break the degeneracy of crystal-field splitting and tailor the on-site Coulomb interactions and spin configuration. These findings underscore the efficacy of a three-dimensional strain strategy in engineering the long-desired high-temperature ferromagnetic insulators via the manipulation of strong spin-lattice coupling, providing a promising approach for the exploitation of exotic functionalities in correlated oxides.

关键词： Perovskite

来源：评论

学校读者我要写书评

暂无评论

Influence of Laser Power on Grain Refinement of Ti5321G Alloy Fabricated by Laser Powder Direct Energy Deposition Assisted with Ultrasonic Energy Field

引用

advanced engineering Materials 2025年

作者： Diao, Mingxia Guo, Chunhuan Wang, Shuai Li, Liyu Dong, Tao Xin, Shewei Sun, Zhonggang Chen, Zubin Konovalov, Sergey Jiang, Fengchun Key Laboratory of Superlight Materials & Surface Technology Ministry of Education College of Materials Science and Chemical Engineering Harbin Engineering University Harbin150001 China Shandong Provincial Key Laboratory of Additive Manufacturing Technology & Equipment Harbin Engineering University Yantai Graduate School Yantai264006 China Titanium Alloy Research Institute Northwest Institute for Nonferrous Metal Research Xi'an710016 China Tech Institute for Advanced Materials College of Materials Science and Engineering Nanjing Tech University Nanjing210009 China Physics Department Siberian State Industrial University 42 Kirov Street Novokuznetsk654007 Russia

Herein, laser power, as one influenced factor, is used to investigate the evolution of microstructure refinement in Ti5321G alloys fabricated by laser powder direct energy deposition (LP-DED) assisted with ultrasonic energy field (UEF). The microstructures and mechanical properties of Ti5321G deposition layers at high temperature assisted with UEF under 1800, 2100, 2400, and 2700 W are characterized and measured. The results show that the microstructure refinement is promoted and the equiaxed grains region is expanded with increasing laser power. The probability of equiaxed grains rises ≈3 times from 1800 to 2700 W. In addition, the refinement of grain structure with increasing laser power substantially weakens and diminishes the texture density. Thoroughly, the recovery of dislocations dominates from 1800 to 2100 W, while recrystallization becomes the dominant process under 2700 W. In addition, the recrystallization fraction increases from 8.2% under 1800 W to 32.3% under 2700 W. It is beneficial to study the effects of laser power on Ti5321G alloys, fabricated by UEF-assisted LP-DED, for regulating the microstructures and providing the basis for subsequent studies of recrystallization mechanisms. © 2025 Wiley-VCH GmbH.

关键词： Grain refinement

来源：评论

学校读者我要写书评

暂无评论

Stacking, Strain-engineering Induced Altermagnetism, Multipiezo Effect, and Topological State in Two-Dimensional Materials

arXiv

引用

arXiv 2025年

作者： Xun, Wei Liu, Xin Zhang, Youdong Wu, Yin-Zhong Li, Ping Jiangsu Engineering Research Center for Design and Application of Intelligent Detection Equipment School of Electronic Engineering Jiangsu Vocational College of Electronics and Information Huaian223003 China School of Physical Science and Technology Suzhou University of Science and Technology Suzhou215009 China State Key Laboratory for Mechanical Behavior of Materials Center for Spintronics and Quantum System School of Materials Science and Engineering Xi’an Jiaotong University Shaanxi Xi’an710049 China State Key Laboratory for Surface Physics Department of Physics Fudan University Shanghai200433 China State Key Laboratory of Silicon and Advanced Semiconductor Materials Zhejiang University Hangzhou310027 China

Altermagnetism, as a newly identified form of unconventional antiferromagnetism, enables the removal of spin degeneracy in the absence of net magnetization that provides a platform for the low power consumption and ultra-fast device applications. However, the rare attention has been paid to the relationship between stacking, strain and altermagnet, multipiezo effect and topological state. Here, we propose a mechanism to realize the altermagnet, multipiezo effect, and topological state in two-dimensional materials by the stacking and strain engineering. Based on the analysis of symmetry, we find that the spin splitting feature related to the Ut, PTt, MzUt, or MzPTt symmetries in altermagnet multilayers. In addition, we find that the stacking engineering can effectively realize the transform from antiferromagnetism to altermagnetism and semiconductor to metal for the Jauns bilayer V2SeTeO. More interestingly, the strain not only induces an intriguing multipiezo effect, encompassing the piezovalley, piezomagnetism and piezoelectric, but also achieves the abundant topological phase. Our findings offer a generalized direction for manipulating the spin splitting, valley polarization, and topological states, promoting practical application of valleytronic and spintronic devices based on two-dimensional altermagnets. © 2025, CC BY.

关键词： Antiferromagnetism

来源：评论

学校读者我要写书评

暂无评论

Creation of Magnetic Skyrmions in Two-Dimensional Van Der Waals Ferromagnets by Lattice Distortion

SSRN

引用

SSRN 2025年

作者： Zhang, Tingjia Yang, Chendi Lv, Xiaowei Zhao, Tuoyu Shi, Wu Li, Wei Liang, Jia Che, Renchao School of Materials and Chemistry University of Shanghai for Science and Technology Shanghai200093 China Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative Materials Academy for Engineering and Technology Advanced Coatings Research Center of Ministry of Education of China Fudan University Shanghai200438 China State Key Laboratory of Surface Physics Institute for Nanoelectronic Devices and Quantum Computing Fudan University Shanghai200433 China Zhangjiang Fudan International Innovation Center Fudan University Shanghai201210 China Department of Physics Fudan University Shanghai200433 China Department of Materials Science State Key Laboratory of Photovoltaic Science and Technology Fudan University Shanghai200433 China

Two-dimensional (2D) van der Waals (vdW) ferromagnets provide an excellent platform for exploring exotic physical phenomena such as magnetic skyrmions and quantum topological phases. However, the centrosymmetric crystal structure inherent in these 2D vdW ferromagnets theoretically precludes the formation of magnetic skyrmions and topological phases. In this study, we investigate the origin of the absence of magnetic skyrmions in 2D vdW ferromagnets and propose an effective strategy to induce lattice distortion through doping, thereby enabling the formation of magnetic skyrmions. Specifically, we demonstrate that Co doping in Fe3GeTe2 leads to significant lattice distortion, transforming the original centrosymmetric crystal structure into a non-centrosymmetric one. This structural modification enables the emergence of a considerable Dzyaloshinskii-Moriya interaction (DMI), giving rise to Néel-type skyrmions. Additionally, the scalar spin chirality of these magnetic skyrmions acts as a virtual magnetic field, thereby inducing the topological Hall effect (THE) in Co-doped Fe3GeTe2. Our findings present a reliable method to manipulate spin textures and induce the THE in 2D vdW ferromagnets with non-zero DMI through lattice distortion, offering a promising route for the development of vdW ferromagnet-based spintronic devices. © 2025, The Authors. All rights reserved.

关键词： Van der Waals forces

来源：评论

学校读者我要写书评

暂无评论

Fast Warming Over the Mongolian Plateau a Catalyst for Extreme Rainfall Over North China

引用

Geophysical Research Letters 2025年第8期52卷

作者： Gu, Jun Zhao, Chun Xu, Mingyue Ma, Yuanyuan Hu, Zhiyuan Jin, Chen Guo, Jianping Geng, Tao Cai, Wenju Deep Space Exploration Laboratory/School of Earth and Space Sciences/CMA-USTC Laboratory of Fengyun Remote Sensing/State Key Laboratory of Fire Science/Institute of Advanced Interdisciplinary Research on High-Performance Computing Systems and Software University of Science and Technology of China Hefei China Laoshan Laboratory Qingdao China CAS Center for Excellence in Comparative Planetology University of Science and Technology of China Hefei China Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Lanzhou China Key Laboratory for Climate Change and Natural Disaster Studies of Guangdong Province School of Atmospheric Sciences Sun Yat-sen University Zhuhai China Southern Marine Science and Engineering Guangdong Laboratory Zhuhai China State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing China and Physical Oceanography Laboratory Ocean University of China Qingdao China

Extreme rainfall events are becoming increasingly severe under a warming climate. North China has experienced several catastrophic rainfall events, of which the rainstorm in 2023 was particularly severe inducing unprecedented damage. Since 1980, the neighboring Mongolian Plateau (MP) has been warming at a rate three times the global average, faster than the surrounding regions. Whether a link exists between extreme rainfall in North China and the fast MP warming is unknown. Here, using global variable-resolution atmospheric model with convection-permitting capability over North China, we find the rapid warming trends, particularly over the MP, are highly conducive to extreme rainfall over North China. In the 2023 case, the fast MP warming induced an anomalous terrestrial high, which in the Western North Pacific Subtropical High created a strong high-pressure system over North China. This system obstructed northeastward movement of Typhoon Doksuri, concentrating moisture supply which prolonged and intensified the extreme. © 2025. The Author(s).

关键词： Global warming

来源：评论

学校读者我要写书评

暂无评论

Transparent Organic Glass With Bright Triplet Excitons for High-Spatial-Resolution Indirect X-Ray Imaging via Heavy Metal Halide Incorporation

引用

advanced Optical Materials 2025年第10期13卷

作者： Xu, Ziwei Li, Nan Feng, Xiaolong Yan, Xiangyang He, Tong Zhang, Lu Liu, Shengzhong Yang, Zhou Key Laboratory of Applied Surface and Colloid Chemistry Ministry of Education Shaanxi Key Laboratory for Advanced Energy Devices Shaanxi Engineering Lab for Advanced Energy Technology Institute for Advanced Energy Materials School of Materials Science and Engineering Shaanxi Normal University Xi'an 710119 China School of Chemistry and Chemical Engineering Shaanxi Normal University Xi'an 710062 China Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China University of the Chinese Academy of Sciences Beijing 100039 China

Organic scintillators are emerging as promising candidates for indirect X-ray imaging due to their tunable luminescent properties. However, achieving high transparency while maintaining a high content of organic luminescent material in organic scintillation pellets remains a challenge, which limits their imaging performance. In this study, a transparent luminescent organic glass based on ethyl-triphenyl-phosphonium chloride (ETPCl) is presented, which exhibits bright exciton emission and enhance X-ray attenuation through the incorporation of lead halide. Remarkably, the addition of lead halide does not compromise the glass's high transparency, which remains ≈90% in the 400–800 nm wavelength range. Transient absorption measurements further reveal that the presence of heavy atoms enhances intersystem crossing and improves triplet emission efficiency, increasing the photoluminescence quantum yield from 7.1% in pure ETPCl glass to 35.4% in glass containing 10 mol.% PbCl₂. Additionally, the heavy atom effect enhances X-ray attenuation, leading to increased radioluminescence intensity. X-ray imaging experiments demonstrate a spatial resolution of up to 19.9 lp mm⁻¹ at a modulation transfer function value of 0.2. These findings provide a promising approach for fabricating transparent organic scintillator glasses with improved triplet exciton utilization and X-ray attenuation, enabling high-resolution X-ray imaging. © 2025 Wiley-VCH GmbH.

关键词： heavy atom effect imaging scintillator spatial resolution triplet emission

来源：评论

学校读者我要写书评

暂无评论

A study on corrosion mechanism of defective fluorite-type RE2Hf2O7 (RE=Dy, Yb) material to CMAS attack at 1300 °C: Experiments and Ab initio molecular dynamics simulations

引用

Ceramics International 2025年

作者： Zhao, Hui Miao, Qiang Liang, Wenping Liu, Ruixiang Sun, Shijie Zhang, Xiaofeng College of Materials Science and Technology Nanjing University of Aeronautics and Astronautics Yudao Street 29 Jiangsu Province Nanjing210016 China Wuxi Research Institute Nanjing University of Aeronautics and Astronautics Luonan Street 8 Jiangsu Province Wuxi214154 China National Key Laboratory of Advanced Composites AECC Beijing Institute of Aeronautical Materials Beijing100095 China National Engineering Laboratory for Modern Materials Surface Engineering Technology Institute of New Materials Guangdong Academy of Sciences Guangzhou510651 China

The effectiveness of candidate Dy- and Yb-bearing hafnate materials as thermal barrier coatings (TBCs) in resisting CMAS (calcium-magnesia-alumina-silicon) corrosion at 1300 °C was investigated using both experimental and simulation-based approaches. The observed in-situ CMAS wetting results indicate that the dissolution of DyO1.5 into melts raises the temperature at which corrosion begins. The sticking temperature point of CMAS on the Dy2Hf2O7 surface is 1268 °C, 26 °C higher than that on the Yb2Hf2O7 surface. The experimental results indicate that compared to Yb2Hf2O7, the formation of Dy-bearing garnet products in the reaction of Dy2Hf2O7 with CMAS creates a protective layer that effectively suppresses further CMAS infiltration. The corrosion thickness of Dy2Hf2O7 is only one-half to one-third of that of Yb2Hf2O7 after 1h, 10h, and 20h exposure. The interfacial atomic diffusivity, energy barrier of atom pair and electronegativity characteristics influence the precipitation of products such as apatite and garnet along the Dy- and Yb-bearing hafnate/CMAS interface. The simulated results suggest that the exceptional Al diffusion rate (18.5014 Å2/ps), lower Al-O and Al-Dy bonding energy barriers (0.31890 eV and 0.41921 eV), and the ease of Al dissolution in CMAS polar solution enhance the formation of Dy-bearing garnet. This study explores two novel hafnate materials as TBC candidates and examines the factors influencing their performance from both chemical and physical perspectives, accompanied by a discussion of guidelines for the rare earth selection of CMAS-resistant hafnate TBCs. © 2025 Elsevier Ltd and Techna Group S.r.l.

关键词： Thermal barrier coatings

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：