检索结果-内蒙古大学图书馆

Pressureless densification and properties of high-entropy boride ceramics with B_(4)C additions

Journal of Materials Science & technology 2024年第23期190卷 1-9页

作者： Fawei Wang Liang Xu Ji Zou Jingjing Liu Huayue Liang Wei Ji Weimin Wang Zhengyi Fu Hubei Longzhong Laboratory Wuhan University of Technology Xiangyang Demonstration ZoneXiangyang 441000China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

High entropy boride ceramics have great potential as structural materials serving in extreme ***,their applications are limited by the difficulty of *** the present study,dense(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))B_(2)ceramics with B_(4)C additions were prepared through pressureless sintering at as low as 1900℃.Calculations based on the CALPHAD approach predict that(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))B_(2)starts to melt at about 3315℃whilst B_(4)C additions reduce the temperature and broaden the tempera-ture region where solid and liquid *** showed that the introduction of B_(4)C could trigger the densification of(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))B_(2)at a lower temperature and promote their densification *** relative density of samples with 5 wt%of B_(4)C additions sintered at 1900 and 2000℃was 97.7%and 99.7%,*** the sintering temperature was further increased to 2100℃,the liquid phase was reactively formed,leading to the rapid grain coarsening in samples with B_(4)C *** by well-dispersed B_(4)C grains,the sample with 5 wt%B_(4)C sintered at 2000℃exhibited excellent mechanical properties with the Vickers hardness,flexural strength,and fracture toughness of 21.07±2.09 GPa,547±45 MPa,and 5.24±0.14 MPa m^(1/2),which are comparable or even higher than counterparts sintered under pressure.

关键词： High entropy boride ceramic Microstructure Pressureless sintering Densification Mechanical properties

来源：评论

学校读者我要写书评

暂无评论

Virtual Power Angle Based Excitation Scheme for ESSC with Improved Overcurrent Protection Strategy 26

Virtual Power Angle Based Excitation Scheme for ESSC with Im...

引用

26th International Conference on Electrical Machines and Systems, ICEMS 2023

作者： Palanas, Patrick J. Yu, Kexun Li, Xiaozhe Chen, Xi Xie, Xianfei Huazhong University of Science and Technology State Key Laboratory of Advanced Electromagnetic Technology Wuhan China

ISBN: (纸本)9798350317589

As the number of renewable energy generators increases, maintaining power system frequency and voltage stability becomes a major challenge. The Energy Storage Synchronous Condenser (ESSC), based on doubly-fed machines, has recently attracted attention as a promising solution for providing both frequency and voltage support to weak grids. With emerging grid-forming control schemes, the ESSC could provide both transient V/f support similar to synchronous condensers and even better active power support by releasing rotor kinetic energy over a wide slip range (e.g., ± 0.3). However, the instability risk of the ESSC with the conventional overcurrent protection scheme may degrade the performance of the ESSC during large grid disturbances. To address this issue, this paper analyzes the instability mechanism with droop control and presents a virtual power angle-based excitation scheme for ESSCs with an improved overcurrent protection strategy. The novel excitation scheme improves the synchronous stability of ESSC and enhances its performance during grid frequency droop occasions. Simulation results have verified the effectiveness of the proposed method. © 2023 IEEE.

关键词： Virtual Power Plants

来源：评论

学校读者我要写书评

暂无评论

A multifunctional electrolyte additive for zinc-ion capacitors with low temperature resistant and long lifespan

引用

Journal of Energy Chemistry 2024年第7期94卷 477-485页

作者： Ming Sun Zekai Zhang Shuqing Fu Yifan Zhang Ruoyu Wang Hongchun Mu Cheng Lian Wenqiang Wang Gengchao Wang Shanghai Engineering Research Center of Hierarchical Nanomaterials Shanghai Key Laboratory of Advanced Polymeric MaterialsSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China State Key Laboratory of Chemical Engineering Shanghai Engineering Research Center of Hierarchical NanomaterialsFrontiers Science Center for Materiobiology and Dynamic Chemistryand School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China

Aqueous zinc-ion capacitors (ZICs) are considered as potential candidates for next generation electrochemical energy storage devices due to their high safety and low ***,the existing aqueous ZICs usually have the problems of zinc dendrite growth and unsatisfactory performance at low ***,an erythritol (Eryt) additive with inhibition of zinc dendrites and anti-freezing capability was introduced into the *** experimental characterization and theoretical calculation confirm that the Eryt adsorbed on the surface of zinc anodes regulates the deposition orientation of Zn^(2+) and inhibits the formation of *** also reconstructs the solvation structure in the electrolyte to reduce water activity,enabling the electrolyte to have a lower freezing point for operation at low *** the assistance of Eryt,the Zn||Zn symmetric cell exhibits a long cycle life of 2000 h,while the ZIC assembled with activated carbon (AC) cathode and zinc anode (Zn||AC) maintains a capacity retention of 98.2% after 30,000 cycles at a current density of 10 A g^(-1)(even after 10,000 cycles at-20°C,the capacity retention rate reached 94.8%.).This work provides a highly scalable,low-cost and effective strategy for the protection of the anodes of low-temperature aqueous ZICs.

关键词： Zinc-ioncapacitors Electrolyte additive Dendrite-free Freeze-resistant electrolyte

来源：评论

学校读者我要写书评

暂无评论

Effect of icosahedral phase formation on the stress corrosion cracking(SCC)behaviors of the as-cast Mg-8%Li(in wt.%)based alloys

引用

Journal of Magnesium and Alloys 2024年第1期12卷 225-236页

作者： Shuo Wang Daokui Xu Dongliang Wang Zhiqiang Zhang Baojie Wang Key Lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang110819China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China Engineering Research Center of Advanced Materials Preparing Technology Ministry of EducationNortheastern UniversityShenyang110819China School of Environmental and Chemical Engineering Shenyang Ligong UniversityShenyang110159China Binzhou Institute of Technology BinzhouShandong Province256606China Shandong Key Laboratory of Advanced Aluminium Materials and Technology BinzhouShandong Province256606China

Through exploring the stress corrosion cracking(SCC)behaviors of the as-cast Mg-8%Li and Mg-8%Li-6%Zn-1.2%Y alloys in a 0.1 M NaCl solution,it revealed that the SCC susceptibility index(I_(SCC))of the Mg-8%Li alloy was 47%,whilst the I_(SCC)of the Mg-8%Li-6%Zn-1.2%Y alloy was 68%.Surface,cross-sectional and fractography observations indicated that for the Mg-8%Li alloy,theα-Mg/β-Li interfaces acted as the preferential crack initiation sites and propagation paths during the SCC *** regard to the Mg-8%Li-6%Zn-1.2%Y alloy,the crack initiation sites included the I-phase and the interfaces of I-phase/β-Li andα-Mg/β-Li,and the preferential propagation paths were the I-phase/β-Li andα-Mg/β-Li ***,the SCC of the two alloys was concerned with hydrogen embrittlement(HE)mechanism.

关键词： Magnesium-lithium alloy Stress corrosion cracking I-phase Fracture analysis

来源：评论

学校读者我要写书评

暂无评论

Vanadium nitride quantum dots@carbon skeleton anode material synthesized via in situ oxidation initiation strategy

引用

Tungsten 2024年第3期6卷 561-573页

作者： Yi-Han Fu Yuan-You Peng Lei Zhao Tian-Qi He Mei-Mei Yuan Hao Dang Rui Liu Fen Ran State Key Laboratory of Advanced Processing and Recycling of Non-Ferrous Metals School of Materials Science and EngineeringLanzhou University of TechnologyLanzhou 730050China

Vanadium nitride(VN)has received significant attention as a potential negative electrode material due to its remarkable theoretical and physical ***,the electrochemical performance needs to be improved due to its low specific surface area and the issue of being easily dissolved in *** have shown that the composite structure of carbon-coated nano sc ale VN particles could significantly increase the specific surface area of VN,and more importantly,and the carbon matrix can effectively restrain the dissolution of VN particles in the electrolyte,thereby improving its chemical and electrochemical performance,including specific capacity and cycling ***,VN quantum dots are synthesized and protected by uniformly coating the carbon skeleton on its surface via an in situ strategy of oxidation initiation,which initiates dopamine polymerization,forming a crystalline complex of polydopamine and *** heat treatment,the product is a composite material with VN quantum dots embedded in the amorphous carbon *** resulting smallsized and crosslinked carbon particles formed a graded pore structure,more reasonable channels provided for electrolyte ions transport *** the composite material was used as the negative electrode material for supercapacitors,it exhibits the specific capacity of 391.9 F·g^(-1)at a current density of 0.5 A·g^(-1)and excellent capacity retention rate of 83.6%after *** synthesis method of this quantum dot could be applied to other metal compounds and has potential applications in catalysis,environmental protection,and other fields.

关键词： In situ initiation Vanadium nitride Quantum dots Anode Supercapacitors

来源：评论

学校读者我要写书评

暂无评论

A Fast Transient Control Method for Dual-Bridge Series Resonant Converter 2

A Fast Transient Control Method for Dual-Bridge Series Reson...

引用

2nd IEEE International Power Electronics and Application Symposium, PEAS 2023

作者： Li, Zhuolan Zhang, Yu School of Electrical and Electronic Engineering Huazhong University of Science and Technology State Key of Laboratory of Advanced Electromagnetic Engineering and Technology Wuhan China

ISBN: (纸本)9798350313765

Under extended-phase-shift (EPS) modulation, both the internal phase-shift angle and the external phase-shift angle will have large step changes when the dual-bridge series resonant converter (DBSRC) rapidly adjusts the transmission power. This will cause serious oscillations in the resonant current and resonant voltage of DBSRC and threaten the safety of the converter. This paper analyzes the transient process produced by sudden changes in phase shift angles under EPS modulation. Then a fast transient control method is proposed for suppressing the oscillation by utilizing both internal and external phase-shift angles, which controls the transient process within one switching cycle and achieves a smooth transition of transmission power. Besides, impact and oscillation on the resonant current and resonant voltage during transient processes are significantly reduced. Finally, the performance of the control method is verified based on experimental and simulation results. © 2023 IEEE.

关键词： DBSRC EPS fast transient control oscillation impact series resonant

来源：评论

学校读者我要写书评

暂无评论

Aggregation-Dependent Polymer Photochromism via Double Intramolecular Hydrogen Bonds from Excited state Intramolecular Proton Transfer

引用

中国化学（英文版） 2025年第8期43卷 879-888页

作者： Jingyuan Zhou Huan Hu Mingzhi Chen Yongjie Li Xin Cheng Zhimin M Shui Hu Zhiyong Ma Beijing Advanced Innovation Center for Soft Matter Science and Engineering State Key Laboratory of Organic-Inorganic CompositesCollege of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China College of Engineering Peking UniversityBeijing 100871China Center of Advanced Elastomer Materials College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China Beijing Advanced Innovation Center for Soft Matter Science and Engineering State Key Laboratory of Organic-Inorganic CompositesCollege of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China Guangdong Provincial Key Laboratory of Functional and Intelligent Hybrid Materials and Devices South China University of TechnologyGuangzhouGuangdong 510640China

Excited-state intramolecular proton transfer(ESIPT)involves photochemical tautomerization between two excited states(E* and K*)via intramolecular proton *** polymer photochromism based on the photochemical tautomerization of organic ESIPT molecules has been rarely *** report the ESIPT molecule HBT-2OH exhibits concentration-dependent photochromic behavior in a polyurethane(PU)*** low concentrations,HBT-2OH primarily exists in the trans-enol configuration without intramolecular OH…N hydrogen bonds in PU,emitting blue fluorescence at～464 nm(enol emission).Upon UV irradiation,the dihedral angle between the proton donor and acceptor twists to form an intramolecular OH…N H-bond,converting trans-enol to cis-enol and resulting in ESIPT with pale yellow fluorescence at～603 nm(keto emission).The photochromic effect of HBT-2OH@PU diminishes at high concentrations due to that aggregation favors the cis-enol *** molecules HBT,HBO-2OH,and HBI-2OH show no photochromism in PU,confirming that ethanolyl branches and intramolecular OH…S hydrogen bonds stabilize the trans-enol configuration of *** these molecules into PMMA and PCL networks demonstrates that increased free volume and smaller aggregates enhance photochromism by reducing resistance to dihedral angle *** functional theory(DFT)calculations further confirm stable intramolecular heteroatomic hydrogen bonds(OH…S)exist in *** study offers new theoretical insights and opens avenues for research on polymer based photochromic materials.

关键词： Polymer photochromism ESIPT Hydrogen bond Heteroatom effect Free volume

来源：评论

学校读者我要写书评

暂无评论

Antioxidant Migration on Dielectric Properties of Long-term Impregnated Insulating Oil 23

Antioxidant Migration on Dielectric Properties of Long-term ...

引用

23rd International Symposium on High Voltage engineering, ISH 2023

作者： Wang, Yucheng Li, Hua Huang, Ziqin Lin, Fuchang State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic Engineering Huazhong University of Science & Technology Wuhan China

ISBN: (纸本)9781839539954

High voltage capacitors are widely used in electrical power systems. For better capability in applications, capacitors are impregnated with insulating oil. Polypropylene in its natural state is inherently unstable and degrades when exposed to oxygen. To avoid oxidation that occurs in the process of film forming, antioxidants are developed and used. In this paper, the polypropylene casts added respectively with antioxidant 1010, 3114, 330 and BHT were long-term impregnated in benzyl toluene oil. Secondly, the frequency domain dielectric spectroscopy method was used to study the dielectric properties of the oil. In addition, the effect of antioxidants on the polarization relaxation process of insulating oil was analyzed. The results indicate that antioxidants and small molecular polypropylene in the amorphous region of the film migrate to the oil during long-term impregnation, resulting in increases in relative dielectric constant Εr, dielectric loss tanδ and dc conductivity σdc, and affect the polarization relaxation process. Among these antioxidants, antioxidant 1010 has the greatest impact on insulating oil, while antioxidant 330 has the least impact. © The Institution of engineering & technology 2023.

关键词： Dielectric losses

来源：评论

学校读者我要写书评

暂无评论

Design of a 13 Tesla Hybrid Magnet

Design of a 13 Tesla Hybrid Magnet

引用

2023 IEEE International Conference on Applied Superconductivity and electromagnetic Devices, ASEMD 2023

作者： Yang, Zhixing Ren, Li Duan, Pu Xu, Ying Shi, Jing Huazhong University of Science and Technology The State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic Engineering Wuhan China

ISBN: (纸本)9798350301571

The Iron-based superconductors(IBS) have high upper critical field, low anisotropy and strong current carrying capacity, which are expected to be the next-generation high temperature superconductors. This paper describes a 13 Tesla hybrid magnet using YBCO tapes and iron-based tapes. The design approach is aimed at verifying the superiority of Iron-based superconducting tapes using a shorter length of IBS tapes. The support structure is designed to improve the mechanical stability of magnets. Through mechanical analysis, it is verified that the magnet meets the design requirements and the operation stability. © 2023 IEEE.

关键词： hybrid magnet iron-based superconductor magnet design

来源：评论

学校读者我要写书评

暂无评论

Cycling performance of layered oxide cathode materials for sodium-ion batteries

引用

International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1720-1744页

作者： Jinpin Wu Junhang Tian Xueyi Sun Weidong Zhuang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory for Green Recovery and Extraction of Rare and Precious Metals University of Science and Technology BeijingBeijing 100083China

Layered oxide is a promising cathode material for sodium-ion batteries because of its high-capacity,high operating voltage,and simple *** performance is an important criterion for evaluating the application prospects of ***,facing challenges,including phase transitions,ambient stability,side reactions,and irreversible anionic oxygen activity,the cycling performance of layered oxide cathode materials still cannot meet the application ***,this review proposes several strategies to address these ***,bulk doping is introduced from three aspects:cationic single doping,anionic single doping,and multi-ion ***,homogeneous surface coating and concentration gradient modification are *** addition,methods such as mixed structure design,particle engineering,high-entropy material construction,and integrated modification are ***,a summary and outlook provide a new horizon for developing and modifying layered oxide cathode materials.

关键词： sodium-ion battery layered oxide materials cycling performance bulking doping surface coating concentration gradient mixed structure high-entropy

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：