检索结果-内蒙古大学图书馆

SSRN 2023年

作者： Li, Yuqiang Li, Yuhong Zhang, Qiang Su, Ningning Sun, Jinlu Xiao, Ningru Liu, Yang Liu, Yuyao Ning, Pingfan Liu, Hongwei Tianjin Key Laboratory of Optoelectronic Detection Technology and Systems School of Electronics and Information Engineering Tiangong University Tianjin300387 China Key Laboratory of Smart Grid of Ministry of Education School of Electrical and Information Engineering Tianjin University Tianjin300072 China School of Semiconductor and Physics North University of China Taiyuan030051 China Engineering Research Center of High Power Solid State Lighting Application System Ministry of Education Tiangong University Tianjin300387 China School of Physical Science and Technology Tiangong University Tianjin300387 China

The high-pressure electronic structure and electrical properties of Mg2Pb are investigated from ambient pressure to 42 GPa by first-principles calculation. Mg2Pb undergoes reversible structural transitions from Fm-3m structure to Pnma structure and then to P63/mmc structure. The structural phase transitions are determined respectively at around 6 GPa and 28 GPa using pressure-dependent enthalpy calculations, which are also reflected from the cell volume collapse and discontinuous axial ratios of lattice constants. The sliding of Mg and Pb atomic layers is revealed via the Mg1-Pb-Mg2 atom pair during structural phase transitions, corresponding to abrupt decrease of c/b and a/b. The semimetal-to-metal transition is also observed at approximately 28 GPa owing to energy-band closure, whilst metallic character is strengthened with increasing pressure. The paper is prone to explore the structural phase transition and metallization of Mg2Pb-type family in theory under extreme conditions. © 2023, The Authors. All rights reserved.

关键词： Electronic structure

来源：评论

学校读者我要写书评

暂无评论

Pressure-Dependent Compressibility of K2x(Co3)2 (X=Ca, Mg) Under High Pressure

SSRN

引用

SSRN 2023年

作者： Tian, Haitao Li, Yuhong Zhang, Qiang Su, Ningning Sun, Jinlu Xiao, Ningru Liu, Yuyao Zhang, Jianxin Liu, Hongwei Li, Yuqiang Tianjin Key Laboratory of Optoelectronic Detection Technology and Systems School of Electronics and Information Engineering Tiangong University Tianjin300387 China Key Laboratory of Smart Grid of Ministry of Education School of Electrical and Information Engineering Tianjin University Tianjin300072 China School of Semiconductor and Physics North University of China Taiyuan030051 China Engineering Research Center of High Power Solid State Lighting Application System of Ministry of Education Tiangong University Tianjin300387 China School of Physical Science and Technology Tiangong University Tianjin300387 China

The high-pressure phase transition behaviors and pressure-dependent compressibility are investigated on K2X(CO3)2 using first-principles calculation from ambient pressure to 30 GPa. The reversible structural phase transitions of K2X(CO3)2 are determined based on enthalpy difference and cell volume collapses. The pressure point of structural phase transitions of K2Ca(CO3)2 is obtained at around 3.3 GPa and 10.3 GPa, while that is found at about 6.2 GPa and 22.6 GPa for K2Mg(CO3)2. Compared with the high axial rigidity of C-O bonds in [CO3] groups, the Ca+ and Mg+ coordination polyhedron show much more compressible. The displacement behavior of the Ca+ and Mg+ coordination polyhedron occurs simultaneously with the rotation behavior of [CO3] groups during compression, and reverses induced by the structural phase transition. © 2023, The Authors. All rights reserved.

关键词： Crystal structure

来源：评论

学校读者我要写书评

暂无评论

Reliability Evaluation of a Regional Integrated Energy System Based on Complex Network Theory

Reliability Evaluation of a Regional Integrated Energy Syste...

引用

Sustainable power and Energy Conference (iSPEC)

作者： Jifeng Li Kuizheng Song Xingtang He Hao Luo Dalian Electric Power Supply Company State Grid Liaoning Electric Power Supply Co. Ltd Dalian China Dispatching and Control Center State Grid Liaoning Electric Power Supply Co. Ltd Shenyang China Key Laboratory of the Ministry of Education on Smart Power Grids Tianjin University Tianjin China Key Laboratory of Modern Power System Simulation and Control & Renewable Energy Technology Northeast Electric Power University Jilin China

ISBN: (纸本)9781665414401

Most of the methods currently used to evaluate the reliability of integrated energy supply mainly consider such systems on a microgrid scale and focus on the effects of interactions among various energy carriers on the overall energy supply reliability of the system. As a result, it is difficult to analyze the system reliability in terms of its topology. Therefore, this paper proposes an approach for evaluating the reliability of a regional integrated energy system based on complex network theory. First, the feasibility of complex network theory application was analyzed based on the structural framework of the regional integrated energy system. Then, a weighted complex network model containing network characteristics was constructed by improving the “distance” parameter in the complex network theory. Employing this model enabled the proposal of reliability evaluation indices, including nodes and the entire system, from the perspective of the system network topology. Finally, the effectiveness and applicability of the developed method were verified by constructing a test system. The application of complex network theory for reliability evaluations of regional integrated energy systems described in this paper provides guidance for planning and constructing future systems at the level of topology reliability.

关键词： Couplings Complex networks Microgrids Energy conversion Reliability theory Propagation losses Topology

来源：评论

学校读者我要写书评

暂无评论

Structural And Electronic Properties Of Weyl Semimetal Wte2 Under High Pressure

SSRN

引用

SSRN 2023年

作者： Li, Yuqiang Li, Yuhong Zhang, Qiang Liu, Xiaofeng Xiao, Ningru Ning, Pingfan Wang, Jingjing Liu, Yang Zhang, Jianxin Liu, Hongwei Tianjin Key Laboratory of Optoelectronic Detection Technology and Systems School of Electronic and Information Engineering Tiangong University Tianjin300387 China Key Laboratory of Smart Grid Ministry of Education School of Electrical and Information Engineering Tianjin University Tianjin300072 China Tianjin San’an Optoelectronics Co. Ltd. Tianjin300384 China Engineering Research Center of High Power Solid State Lighting Application System Ministry of Education Tiangong University Tianjin300387 China School of Physical Science and Technology Tiangong University Tianjin300387 China

The structural and electronic properties of WTe2 are studied from ambient pressure to 30.0 GPa. The pressure-induced structural phase transition is found from Td phase (Pnm21, No. 31) to 1T′ phase (P21/m, No. 11) above 10.0 GPa by lattice offset, which is also reflected at approximately 11.2 GPa based on the discontinuous electrical parameters. A pair of hole wave and electron wave packets of Td phase gradually overlap revealing the reversible Td-to-1T′ phase structural transition. WTe2 is observed to undergo semimetal-to-semiconductor transition owing to the calculated energy band up to 15 GPa, which is also observed at 11.2 GPa according to the resistivity-temperature curves under compression and decompression conditions. The electronic density of states at the Fermi level is mainly contributed by the d orbital of W and the p and s orbital of Te. The photoconductivity property is shown by the theoretical and experimental methods. © 2023, The Authors. All rights reserved.

关键词： Electronic properties

来源：评论

学校读者我要写书评

暂无评论

Research on Short-time Current Test Method of DC Circuit Breaker Used in DC grid

Research on Short-time Current Test Method of DC Circuit Bre...

引用

International Conference on power System technology (powerCON)

作者： Xiuhuan Wang Junchuan Zhou Ersong Chen State Key Laboratory of Advance Power Transmission Technology Global Energy Interconnection Research Institute CO. LTD Beijing China Beijing Key Laboratory of High Power Electronic Global Energy Interconnection Research Institute CO. LTD Beijing China State Grid Hebei Electric Power Research Institute Shijiazhuang China

ISBN: (纸本)9781665407380

DC power grid technology puts forward new requirements for equipment. High-voltage DC circuit breakers with fast breaking capability are the core equipment of DC power grids. The existing test technology can not meet the short-term current tolerance requirements of DC circuit breakers in terms of power. In order to solve this problem, this paper analyzes the short-term current stress tolerated by the DC circuit breaker in the DC grid, proposes a test method and test circuit topology based on the loss and junction temperature equivalence are proposed, and builds a PSCAD/EMTDC electromagnetic transient simulation model. Taking the Kangbao Station of Zhangbei Project as an example, the short-term current withstand test of the DC circuit breaker was simulated and verified. The simulation results show that the test circuit can effectively implement the short-term current stress assessment of the DC circuit breaker. The design provides guidance for the test platform.

关键词： Analytical models power supplies Circuit breakers Simulation HVDC transmission power grids Hybrid power systems

来源：评论

学校读者我要写书评

暂无评论

First-Principles Study of Electronic Structure and Metallization of Xpse3 (X=Fe, Mn) Under High Pressure

SSRN

引用

SSRN 2023年

作者： Li, Yuqiang Li, Yuhong Zhang, Qiang Su, Ningning Sun, Jinlu Xiao, Ningru Liu, Yang Liu, Yuyao Zhang, Jianxin Liu, Hongwei Tianjin Key Laboratory of Optoelectronic Detection Technology and Systems School of Electronics and Information Engineering Tiangong University Tianjin300387 China Key Laboratory of Smart Grid of Ministry of Education School of Electrical and Information Engineering Tianjin University Tianjin300072 China School of Semiconductor and Physics North University of China Taiyuan030051 China Engineering Research Center of High Power Solid State Lighting Application System of Ministry of Education Tiangong University Tianjin300387 China School of Physical Science and Technology Tiangong University Tianjin300387 China

The pressure-induced structural phase transition and metallization of FePSe3 and MnPSe3 are investigated from ambient pressure to 40 GPa by first-principles calculation. FePSe3 and MnPSe3 undergo reversible structural transitions from R-3 structure to C2/m structure and then to P-31m structure. The structural phase transitions of FePSe3 are at about 6 GPa and 13 GPa, while the pressure points are at approximately 13 GPa and 25 GPa for MnPSe3, reflecting from pressure-dependent enthalpy calculation, cell volume collapses, and sudden changes of lattice parameters. The computed metallization transition is also observed at around 8 GPa and 16 GPa owing to energy-band closure for FePSe3 and MnPSe3, respectively. The metallic character of XPSe3 is strengthened with increasing pressure based on the electronic energy band and electron density of states. The layer sliding of atoms is revealed using the P2-P3 atom pair of XPSe3 during structural phase transitions. The paper is conducive to considering the electronic structure and metallization of transition metal thiophosphates XPSe3-type family under extreme conditions. © 2023, The Authors. All rights reserved.

关键词： Electronic structure

来源：评论

学校读者我要写书评

暂无评论

Failure Modes and Energy Handling Capability of ZnO Varistors with Different Electrode Edge Margins Stressed by Current Impulses

Failure Modes and Energy Handling Capability of ZnO Varistor...

引用

International Conference on High Voltage Engineering and Application, ICHVE

作者： Zhen Fang Bowen Wang Zhiyao Fu State Key Laboratory of Disaster Prevention & Reduction for Power Grid Transmission and Distribution Equipment State Grid Hunan Electric Power Company Disaster Prevention and Reduction Center Changsha China State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology Wuhan China

ISBN: (数字)9781728155111

ISBN: (纸本)9781728155128

ZnO varistors with different electrode edge margins were tested under 2 ms rectangular impulses and 4/10 μs impulses. A certain margin is necessary to be left between the electrode edge and the edge of the ZnO varistor so that the electrical performance, especially energy handling capability, will not be scattered and limited. Experiments have shown that ZnO varistors with 0.5 mm margin performed better than that with 0 mm, 0.3 mm and 1 mm margins on the whole. During the impulse test, some varistor samples failed. The failure modes under current impulses, including puncture, cracking and flashover were discussed.

关键词： Varistors Electrodes Flashover Zinc oxide II-VI semiconductor materials Temperature measurement Cameras

来源：评论

学校读者我要写书评

暂无评论

Research on Transforming Effect and Calculation Method of MMC Converter on AC / DC Harmonics

Research on Transforming Effect and Calculation Method of MM...

引用

Sustainable power and Energy Conference (iSPEC)

作者： Liu Cui Guangqiang Peng Jingsong He Jiyang Wu Chizu Mao Ning Jiao State Key Laboratory of HVDC Electric Power Research Institute China Southern Power Grid GuangZhou China Guangdong Provincial Key Laboratory of Intelligent Operation and Control for New Energy Power System GuangZhou China CSG Key Laboratory for Power System Simulation Electric Power Research Institute China Southern Power Grid GuangZhou China Maintenance & Test Center EHV Power Transmission Company Guangzhou CSGKEY LABORATORY FOR DC TRANSMISSIONEQUIPMENT STATE EVALUATION AND FAULT DIAGNOSIS GuangZhou China College of Electrical Engineering and Information Technology Sichuan University Chengdu China

ISBN: (纸本)9781665414401

Modular multilevel converter (MMC) is currently the most concerned voltage source converter topology in the field of flexible direct current transmission (VSC-HVDC). Due to its non-linear characteristics, harmonic components will inevitably be generated in AC and DC systems, which may affect the operation of equipment and system, cause protection equipment to malfunction, and cause interference to neighboring communications. The MMC converter is a non-linear device, which can be considered as an amplifying modulator with voltage and current conversion functions. The AC and DC networks are coupled to each other through the MMC converter to generate dynamic harmonic interaction. In recent years, harmonic instability problems have appeared in many VSC-HVDC projects. Compared with other converter topologies, the transfer relationship of harmonics on the AC and DC sides of MMC converters has not been studied in depth. In this paper, by studying the AC/DC harmonic conversion characteristics of MMC converters, it reveals the conversion law of MMC converters between AC/DC harmonics; through theoretical derivation, the quantitative calculation method of MMC harmonic transmission process is given. PSCAD simulation results prove the correctness of the above results.

关键词： Network topology Simulation Bridge circuits Voltage power system harmonics Harmonic analysis Frequency conversion

来源：评论

学校读者我要写书评

暂无评论

Hydrophobicity and high-temperature corrosion resistance nano-modified organic silicone coatings in alternating environments

Corrosion Communications

引用

Corrosion Communications 2025年

作者： Zheng Chen Yao Du Bowen Li Yiliang Lu Cheng Wang Li Xin Shenglong Zhu Fuhui Wang School of Materials Science and Engineering University of Science and Technology of China Shenyang 110016 China Shi-changxu Innovation Center for Advanced Materials Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China State Key Laboratory of Advanced Power Transmission Technology State Grid Smart Grid Research Institute Co. Ltd. Beijing 102209 China Jiangsu JITRI Road Engineering Technology and Equipment Research Institute Co. Ltd. Xuzhou 220005 China Shenyang National Laboratory for Materials Science Shenyang 110016 China

Three organic silicone coatings containing different contents of nano-sized Ti and Al powders were prepared on 304SS substrates. Their resistance against cyclic corrosion tests was carried out. Each cycle of the corrosion tests includes 22 h of salt spraying test at 35°C and consecutive 2 h of oxidation test at 400°C. The results revealed that the coating with 10 wt.% Ti powders exhibited self-healing performance, the highest corrosion resistance, and the best hydrophobicity. Though addition of nano-Al into the coatings is beneficial to enhancing the hydrophobicity, but results in spallation during corrosion tests. This study demonstrates the correlation between hydrophobicity of nano-modified organic silicone coatings and resistance against corrosion in alternating environments.

关键词： 304 Stainless steel Organic silicone coatings Thermal cycling High temperature corrosion Oxidation

来源：评论

学校读者我要写书评

暂无评论

Optical observations on propagation characteristics of dart leader in natural lightning striking on canton tower 11

Optical observations on propagation characteristics of dart ...

引用

11th Asia-Pacific International Conference on Lightning, APL 2019

作者： Wang, X. Cai, H. Liu, G. Liao, M. Qu, L. Zhao, X. State Key Laboratory of HVDC Transmission Technology Electric Power Research Institute China Southern Power Grid Guangzhou China

ISBN: (纸本)9781728116952

Based on the high-speed video camera and electric field measurement, dart leader propagation prior to four subsequent return strokes (RS) in one negative lightning flash striking on the top of Canton tower has been recorded. The optical observations show that dart leaders develop downward following the same channel path as the first RS event, with the approximate leader durations ranging from 240 μs to 720 μs and interstroke intervals from 21 ms to 76 ms. Two-dimensional (2D) average speeds of dart leader propagation are mainly in the order of 106 m/s. As the increasing stroke order of the subsequent strokes, the corresponding leader could propagate faster, increasing to the order of 107 m/s, and the luminosity of subsequent stroke could be enhanced. Preceding all the subsequent strokes, there is no clear evidence of upward connecting leaders (UCLs) detected on the top of the tower associated with the descending dart leaders. © 2019 IEEE.

关键词： High speed cameras

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：