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SSRN 2023年

作者： Ma, Rui Zhang, Xinfang School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing100083 China State Key Laboratory of Advanced Metallurgy China

The sudden brittle fracture of Ti, Zr and other metals caused by brittle hydride phase usually depends on the hydride network. Common hydride networks include continuous hydride configurations and grain boundary hydride configurations. In this study, pulse electric current is used to effectively repair the embrittlement caused by continuous hydride configuration and grain boundary hydride configuration in pure titanium. The elongation of hydrogenated pure titanium increased from 10% to about 20% after pulse current treatment, with a certain degree of recovery of ultimate tensile strength. This is due to the dissolution of partial hydride after pulse current treatment, and the hydride configuration is destroyed. Considering the introduction of pulse current, pure titanium with hydride configuration is thermodynamic unstable, and the electromigration effect in kinetics also accelerates the desorption of hydrogen atom. The evolution of hydride configuration and the desorption of hydrogen atoms are beneficial to the recovery of mechanical properties of hydrogenated pure titanium. In this study, the problem of hydride embrittlement caused by different hydride configurations in pure titanium was effectively repaired by pulsed electric current, which provided a new pathway and solution for dealing with the hydride induced embrittlement. © 2023, The Authors. All rights reserved.

关键词： Electric fields

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Significantly Enhanced Insulation Resistance Degradation of BaTiO3-Based MLCCs with High Temperature Stability via Defect engineering

Significantly Enhanced Insulation Resistance Degradation of ...

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International Conference on (ICEPT) Electronic Packaging technology

作者： Junhui Tan Lixia Cheng Pengfei Wang Rongxia Huang Zhenxiao Fu Xiuhua Cao Lei Zhang Shuhui Yu Rong Sun Shenzhen Institute of Advanced Electronic Materials Shenzhen Institute of Advanced Technology Chinese Academy of Sciences Shenzhen China School of Electromechanical Engineering Guangdong University of Technology Guangzhou China Guangdong Provincial Key Laboratory of Electronic Functional Materials and Devices Huizhou University Huizhou China State Key Laboratory of Advanced Materials and Electronic Components Guangdong Fenghua Advanced Technology Holding Co. Ltd Zhaoqing China

ISBN: (数字)9798350353808

ISBN: (纸本)9798350353815

Base metal electrodes-multilayer ceramic capacitors (BME-MLCCs) are important equipment components enabling electronic devices to achieve excellent performance, muti-functionality and high integration, which are considered to be a fascinating device for a diverse range of electric applications. However, the service lifespan of MLCCs mainly depends on the insulation resistance (IR) degradation behavior. To solve this problem, the current-voltage (I-V), capacitor-voltage (C-V), thermally stimulated depolarization current (TSDC) characteristics and highly accelerated life test (HALT) of $\text{BaTiO}_{3}$ based BME-MLCCs with superior temperature coefficient of capacitance (TCC) were investigated systematically. It is found that the IR degradation behavior is closely related to the accumulation and migration of oxygen vacancies and space charges. It can be observed from the I-V results that the Ohmic, Schottky type conduction occurs with the increase of dc field in all samples, while Poole-Frenkel effect was only observed in specific samples w ith the re laxati on of trapped space charges and poor reliability. This work explores the degradation mechanism of $\text{BaTiO}_{3}\text{-MLCCs}$ insulation resistance and provides a feasible strategy to improve its reliability.

关键词： Degradation Resistance Insulation Temperature Powders Space charge Capacitance

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Dipole Moment Regulation for Enhancing Internal Electric Field in Covalent Organic Frameworks Photocatalysts

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SSRN 2024年

作者： Zhao, Xiaoying Shang, Shuaishuai Liu, Honglai Peng, Changjun Hu, Jun Key Laboratory for Advanced Materials Joint International Research Laboratory for Precision Chemistry and Molecular Engineering School of Chemistry and Molecular Engineering East China University of Science and Technology 130 Meilong Road Shanghai200237 China State Key Laboratory of Chemical Engineering Department of Chemistry East China University of Science and Technology Shanghai200237 China

Covalent organic frameworks (COFs) have recently emerged as a kind of promising photocatalytic platform in addressing the growing threat of trace pollutants in aquatic environments. Along this, we propose a strategy of constructing internal electric field (IEF) in COFs through the dipole moment regulation, which intrinsically facilitates the separation and transfer of photogenerated excitons. Two COFs of BTT-TZ-COF and BTT-TB-COF are developed by linking the electron-donor of benzotrithiophene (BTT) block and the electron-acceptor of triazine (TZ) or tribenzene (TB) block, respectively. DFT calculations demonstrate TZ block with larger dipole moment can achieve more efficient IEF due to the stronger electron-attractive force and hence narrower bandgap. Moreover, featuring the highly-order crystalline structure for accelerating photo-excitons transfer and rich porosity for facilitating the adsorption, BTT-TZ-COF exhibited an excellent universal performance of photocatalytic degradations of various dyes. Specifically, a superior photodegradation efficiency of 99% Rhodamine B (RhB) is achieved within 20 min under the simulated sunlight. Therefore, this convenient construction approach of enhanced IEF in COFs through rational regulation of the dipole moment can be a promising way to realize high photocatalytic activity. © 2024, The Authors. All rights reserved.

关键词： Excitons

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Utilization of red mud and coal gangue for underground backfill material:Hydration and environmental characteristics

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International Journal of Minerals,Metallurgy and Materials 2025年第6期32卷 1358-1371页

作者： Jie Wang Song Guo Xiaoming Liu Zengqi Zhang School of Metallurgical and Ecological Engineering University of Science and Technology Beijing State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

The large-scale accumulation of industrial solid waste, including red mud and coal gangue, coupled with goafs left by under-ground mining activities, poses significant challenges to sustainable human development. In this study, red mud, coal gangue, and othersolid wastes were used to prepare underground backfilling materials. The utilization rate of the total solid waste reached 95%, with redmud accounting for approximately 40wt% of the total. The unconfined compressive strength, setting time, and slump tests were conduc-ted to evaluate the mechanical properties of the material. At the optimal ratio, the 7-and 28-d strengths reach 4.4 and 6.9 MPa, respect-ively. The initial and final setting times were 200 and 250 min, respectively, whereas the initial and 1-h slump exceed 250 and 210 mm,respectively. X-ray diffraction（XRD）, Fourier-transform infrared spectroscopy（FTIR）, and scanning electron microscopy（SEM） wereemployed to explore the microstructure, phase composition, and chemical bonding within the material. Needle-like, clustered, and granu-lar hydration products were observed, and the primary crystalline structures were identified as ettringite, gmelinite, C–A–S–H, andC–S–H. In addition, a thorough environmental risk assessment was conducted, complemented by detailed economic cost and carbonemission calculations. During the creation of backfill material, hazardous elements from solid waste are immobilized through adsorption,precipitation, and incorporation into the crystal lattice. The immobilization efficiencies for Ni, Al, Cr6+, and As were 97.03%, 94.32%,86.43%, and 84.22%, respectively, at a pH of 8.49. Moreover, the use of solid waste as a raw material results in considerable cost savingsand marked reduction in carbon emissions. This study innovatively promotes the green cycle of alumina production in the bauxite miningindustry.

关键词： red mud underground backfill solid waste hazardous elements

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Optimization on Microstructure and Mechanical Properties of Pm-Ta15 Titanium Plates by Annealing Treatment

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SSRN 2024年

作者： Gao, Ying Zhang, Ce Zhang, Jiazhen Lu, Xin Beijing Advanced Innovation Center for Materials Genome Engineering State Key Laboratory for Advanced Metals and Materials Institute for Advanced Materials and Technology University of Science and Technology Beijing Beijing100083 China National Engineering Research Center for Advanced Rolling Technology National Engineering Research Center for Flat Rolling Equipment Institute of Engineering Technology University of Science and Technology Beijing Beijing100083 China Shunde Innovation School University of Science and Technology Beijing Foshan528399 China

Hot rolling with powder metallurgy (PM) is one of the effective methods to prepare higher alloying and lower cost titanium alloys plates. In this study, the PM-TA15 sintered billets with elemental powders were hot rolled at 1100℃ under 2 passes within ~60% reduction rate in each pass without annealing among passes, and the plates were annealed at 900-1100℃ for 2-4 h after hot rolling. The effects of annealing temperature and time on the microstructure and properties of PM-TA15 plates and their evolution mechanisms were investigated. The results indicated that the anisotropy of the microstructure and properties, plasticity and toughness of the plates was significantly improved. The plates presented finer and more uniform basketweave or bimodal structure, and the grains were controlled by dynamic recovery (DRV) and dynamic recrystallization (DRX) within {0001}, {010} and {20} misorientation, and the maximum texture strength was reduced to less than 1.5. After annealing at 900-1000 °C for 4 h, the tensile strength, yield strength and elongation of the plates were 1041-1051 MPa, 953-963 MPa and 15.5-17.5%, respectively, and the strength difference between different orientations was only 10-15 MPa. The deformation and optimization of the plates depended on the synergistic effects of prismatic, pyramidal and basal slip systems, and texture weakening and microstructure optimization were the key to improving the performance of the PM-TA15 plates. © 2024, The Authors. All rights reserved.

关键词： Anisotropy

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Effect of Periodic Phase Modulation on the Matched Filtering with Insufficient Phase Shift Capability

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IEEE Transactions on Aerospace and Electronic Systems 2024年第3期61卷 5755-5770页

作者： Xu, Hong Wei, Haotian Chen, Hui Chen, Zhanye Zhou, Xiaoyang Xu, Heng Quan, Yinghui Xidian University Hangzhou Research Institute Hangzhou311231 China Southeast University State Key Laboratory of Millimeter Waves Nanjing210096 China Southeast University Institute of Electromagnetic Space Nanjing210096 China Xidian University Xi'an Key Laboratory of Advanced Remote Sensing School of Electronic Engineering Xi'an710071 China Xidian University Department of Remote Sensing Science and Technology School of Electronic Engineering Xi'an710071 China Xidian University Key Laboratory of Collaborative Intelligence Systems Ministry of Education School of Electronic Engineering Xi'an710071 China

Utilizing periodic phase modulation (PPM) can shift the echo spectrum, affecting matched filtering (MF) processing, leading to time delay shift or amplitude attenuation. The prior works on the impact of PPM on MF mainly consider an ideal phase modulation model, where the phase shift is considered to be sufficient. In practical applications, the phase shift capability achieved by physical devices for phase modulation is often insufficient due to factors such as hardware limitations, operating bandwidth, and cost constraints. To address this limitation, this paper investigates the quantitative impact of PPM on the MF under conditions of insufficient phase shift. Firstly, reflection coefficient models for PPM under insufficient phase shifts are established, considering 1-bit and 2-bit conditions. Furthermore, for commonly used radar waveforms such as linear frequency modulation (LFM) and phase-coded modulation (PCM), expressions for MF output results under different bit rates are derived, and a quantitative analysis of the time delay and amplitude attenuation compared with the unmodulated case is conducted. Finally, the correctness of the proposed theoretical model is validated through simulation and measured experiments. © 1965-2011 IEEE.

关键词： Matched filters

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Quasi-Solid-state Ion-Conducting Arrays Composite Electrolytes with Fast Ion Transport Vertical-Aligned Interfaces for All-Weather Practical Lithium-Metal Batteries

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Nano-Micro Letters 2022年第12期14卷 401-414页

作者： Xinyang Li Yong Wang Kai Xi Wei Yu Jie Feng Guoxin Gao Hu Wu Qiu Jiang Amr Abdelkader Weibo Hua Guiming Zhong Shujiang Ding School of Chemistry Xi’an Key Laboratory of Sustainable Energy Materials ChemistryState Key Laboratory of Electrical Insulation and Power EquipmentXi’an Jiaotong UniversityXi’an 710049People’s Republic of China State Key Laboratory for Mechanical Behaviour of Materials Xi’an Jiaotong UniversityXi’an 710049People’s Republic of China Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhouZhejiang 313001People’s Republic of China School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 610054People’s Republic of China Faculty of Science and Technology Bournemouth UniversityTalbot CampusFern BarrowPoole BH125BBUK Institute for Applied Materials-Energy Storage Systems(IAM-ESS) Karlsruhe Institute of Technology(KIT)76344 Eggenstein-LeopoldshafenGermany School of Chemical Engineering and Technology Xi’an Jiaotong UniversityXi’anShaanxi 710049People’s Republic of China Laboratory of Advanced Spectroelectrochemsitry and Li-ion Batteries Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023People’s Republic of China State Key Laboratory of Organic-inorganic Composites Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China

The rapid improvement in the gel polymer electrolytes(GPEs)with high ionic conductivity brought it closer to practical applications in solid-state Li-metal *** combination of solvent and polymer enables quasi-liquid fast ion transport in the ***,different ion transport capacity between solvent and polymer will cause local nonuniform Li+distribution,leading to severe dendrite *** addition,the poor thermal stability of the solvent also limits the operating-temperature window of the *** the ion transport environment and enhancing the thermal stability are two major challenges that hinder the application of ***,a strategy by introducing ion-conducting arrays(ICA)is created by vertical-aligned montmorillonite into *** ion transport on the ICA was demonstrated by 6Li solid-state nuclear magnetic resonance and synchrotron X-ray diffraction,combined with computer simulations to visualize the transport *** with conventional randomly dispersed fillers,ICA provides continuous interfaces to regulate the ion transport environment and enhances the tolerance of GPEs to extreme ***,GPE/ICA exhibits high room-temperature ionic conductivity(1.08 mS cm^(−1))and long-term stable Li deposition/stripping cycles(>1000 h).As a final proof,Li||GPE/ICA||LiFePO_(4) cells exhibit excellent cycle performance at wide temperature range(from 0 to 60°C),which shows a promising path toward all-weather practical solid-state batteries.

关键词： Solid-state batteries Composite electrolytes Vertical-aligned ion-conducting arrays Interfacial ion-conduction mechanism All-weather practical electrolyte design

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Enhanced Cyclic Performance of MgH2/Γ-Mns Composite and Evolution Behavior of the Sulfide

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SSRN 2024年

作者： Wu, Chengzhang Lin, Jiayu Luo, Wenwen Wu, Zhanwen Len, Haiyan Sun, Chenghua Li, Qian State Key Laboratory of Advanced Special Steel Shanghai Key Laboratory of Advanced Ferrometallurgy School of Materials Science and Engineering Shanghai University Shanghai200444 China Centre for Translational Atomaterials Faculty of Science Engineering and Technology Swinburne University of Technology HawthornVIC3122 Australia National Engineering Research Center for Magnesium Alloys College of Materials Science and Engineering Chongqing University Chongqing400044 China

In the present work, three kinds of γ-MnS with different morphologies were prepared by solvothermal method and employed to improve the hydrogen storage properties of MgH2. It was found that spherical γ-MnS had the best catalytic activity. The influences of γ-MnS content and milling time on the hydrogen storage performance of MgH2 were investigated. The initial hydrogen release of MgH2-5(γMnS)-5h composite started at 241 ℃, 4.61 wt.% of hydrogen was desorbed within 20 min at 270 ℃, and 3.59 wt.% of hydrogen was absorbed within 5 min at 150 ℃. The apparent activation energies of hydrogen absorption and desorption of MgH2-5(γMnS)-5h composite decreased to 45.1 and 63.6 kJ/mol, respectively. In addition, the composite also exhibited good cycle performance, which could keep stable in 60 cycles. The results of SEM and TEM declared that the catalyst was uniformly distributed on the matrix during the cycling process, and the worm-like morphology of the sample also had a positive effect on the stability of kinetics. XPS results displayed that γ-MnS remained stable during ball milling, but the characteristic peaks of Mn and α-MnS were observed in the first and tenth hydrogenated samples, while only the peaks of Mn were observed in the sixtieth hydrogenated sample. The formation of Mn not only greatly weakened the Mg-H bond, but also led to a slight increase in cycle capacity. Therefore, γ-MnS-doped MgH2 manifested a good comprehensive hydrogen storage performance. © 2024, The Authors. All rights reserved.

关键词： Magnesium compounds

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Research on transient interaction mechanism of two PMSG considering different nodes and network characteristics 1

Research on transient interaction mechanism of two PMSG cons...

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1st IEEE China International Youth Conference on Electrical engineering, CIYCEE 2020

作者： Mao, Zichen Yuan, Xiaoming State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic Engineering Huazhong University of Science and Technology Wuhan430074 China

ISBN: (纸本)9781728196596

Compared with the traditional AC power system, high proportion of renewable generation and power electronics are the characteristics of the power electronic dominated power system. The multi-time scale problem of the dynamical problems becomes prominent. There are complex interactions between power electronics. First, this paper describes the multi-time scale control links of equipment in the power electronic dominated power system and the mechanism of the multiscale with the example of permanent magnetic synchronous generator (PMSG).Second, a multi-time scale nesting model for analyzing interaction is proposed. Finally, the phenomenon of multi-time scale interaction between two PMSG is explained by simulation, and the influence of different node and network characteristics on the degree of interaction is explored, which provides references for subsequent analytical analysis. © 2020 IEEE.

关键词： Synchronous generators

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Electrospinning Janus Nanofibrous Membrane for Unidirectional Liquid Penetration and Its Applications

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Chemical Research in Chinese Universities 2021年第3期37卷 337-354页

作者： HOU Lanlan LIU Jingchong LI Dianming GAO Yuan WANG Yaqiong HU Rongjun REN Wen XIE Shuixiang CUI Zhimin WANG Nü State Key Laboratory of Petroleum Pollution Control CNPC Research Institute of Safety and Environmental TechnologyBeijing102206P.R.China Key Laboratory of Bioinspired Smart Interfacial Science and Technology of Ministry of Education Beijing Key Laboratory of Bioinspired Energy Materials and DevicesSchool of ChemistryBeijing Advanced Innovation Center for Biomedical EngineeringBeihang UniversityBeijing100191P.R.China

Janus membrane with opposite wettability on its two sides has witnessed an explosion of interest in the field of liquid spontaneous and directional transport for their promising *** advances in fabrication technology and natural bionics have brought remarkable progress for the development of Janus *** the exciting progress,the micro/nanofabrication technique of electrospinning shows advantages in constructing thin porous fibrous membrane materials with controllable surface wettability and hierarchical ***,a brief review of bioinspired Janus membrane for unidirectional liquid penetration fabricated by electrospinning is presented,and the underlying scientific mechanism is discussed with an emphasis on the materials design involving asymmetric surface wettability and micro-topology *** overview of recent emerging applications is also reviewed,with special attentions to liquid separation,water collection,distillation,and smart textile,*** researchers keep to develop more efficient strategies on designing new Janus membrane with higher performances,it has become increasingly important to understand the mechanism of liquid moving dynamics at the asymmetric interface in order to better recognize the scientific limitations currently hindering the field *** last,the challenges currently faced and possible strategies on developing new Janus membranes for optimization and engineering in the future are proposed.

关键词： Electrospinning Nanofiber Janus membrane Unidirectional penetration Wettability gradient

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