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VA族元素修饰对二维AlN电磁性质调控的理论研究

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原子与分子物理学报 2025年第6期42卷 159-166页

作者：莫秋燕陈广萍张颂荆涛吴家隐凯里学院大数据工程学院凯里556011 凯里学院理学院凯里556011 广东开放大学(广东理工职业学院)工程技术学院广州510091

采用基于密度泛函理论的第一性原理计算方法,研究了VA族元素(N、P、As、Sb、Bi)对二维AlN电磁性质的影响.研究发现,VA族元素修饰后,二维AlN的能带结构发生显著劈裂,表明体系转变为磁性材料.同时,导带底部向低能量区域移动,使得二维AlN... 详细信息

采用基于密度泛函理论的第一性原理计算方法,研究了VA族元素(N、P、As、Sb、Bi)对二维AlN电磁性质的影响.研究发现,VA族元素修饰后,二维AlN的能带结构发生显著劈裂,表明体系转变为磁性材料.同时,导带底部向低能量区域移动,使得二维AlN的吸收阈值从紫外线区域扩展至可见光区域.因此,VA族元素的修饰显著调控了二维AlN的电子结构和磁性,为实现可见光响应的光电子和自旋电子器件提供了新思路和可能性.

关键词：二维AlN 第一性原理修饰电子结构

Intelligent casting:Empowering the future foundry industry

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China Foundry 2024年第5期21卷 409-426页

作者： Jin-wu Kang Bao-lin Liu tao jing Hou-fa Shen School of Materials Science and Engineering Key Laboratory for Advanced Materials Processing TechnologyTsinghua UniversityBeijing 100084China

Emerging technological advances are reshaping the casting sector in latest *** technology is evolving towards intelligent casting paradigm that involves automation,greenization and intelligentization,which attracts more and more attention from the academic and industry *** this paper,the main features of casting technology were briefly summarized and forecasted,and the recent developments of key technologies and the innovative efforts made in promoting intelligent casting process were ***,the technical visions of intelligent casting process were also put *** key technologies for intelligent casting process comprise 3D printing technologies,intelligent mold technologies and intelligent process control *** future,the intelligent mold that derived from mold with sensors,control devices and actuators will probably incorporate the Internet of Things,online inspection,embedded simulation,decision-making and control system,and other technologies to form intelligent cyber-physical casting system,which may pave the way to realize intelligent *** is promising that the intelligent casting process will eventually achieve the goal of real-time process optimization and full-scale control,with the defects,microstructure,performance,and service life of the fabricated castings can be accurately predicted and tailored.

关键词： intelligent casting 3D printing intelligent mold process control cyber-physical casting system embedded simulation

Synthesis of α-fluoro-β-amino acids via the Reformatsky reaction of chiral N-tert-butylsulfinylimines with ethyl bromofluoroacetate

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Chinese Chemical Letters 2011年第8期22卷 919-922页

作者： Zhi tao jing Yan GenHuang Feng Ling Qing College of Chemistry Chemical Engineering and Biotechnology Donghua University Shanghai 201620 China Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

Treatment of chiral N-tert-butyl sulfinylimines with ethyl bromofluoroacetate in the presence of activated Zn dust in THF afforded the α-fluoro- β-amino acid derivatives in good yields（70-86%） and moderate diaster... 详细信息

关键词： Fluorinated amino acids Reformatsky reaction N-tert-Butyl sulfinylimine

Anisotropic diffusion of volatile pollutants at air-water interface

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Water Science and Engineering 2013年第2期6卷 153-163页

作者： Li-ping CHEN jing-tao CHENG Guang-fa DENG College of Urban Construction and Safety Engineering Nanjing University of Technology Jiangsu Frontier Electric Technology Co. Ltd.

The volatile pollutants that spill into natural waters cause water pollution. Air pollution arises from the water pollution because of volatilization. Mass exchange caused by turbulent fluctuation is stronger in the direction normal to the air-water interface than in other directions due to the large density difference between water and air. In order to explore the characteristics of anisotropic diffusion of the volatile pollutants at the air-water interface, the relationship between velocity gradient and mass transfer rate was established to calculate the turbulent mass diffusivity. A second-order accurate smooth transition differencing scheme （STDS） was proposed to guarantee the boundedness for the flow and mass transfer at the air-water interface. Simulations and experiments were performed to study the trichloroethylene （C2HC13） release. By comparing the anisotropic coupling diffusion model, isotropic coupling diffusion model, and non-coupling diffusion model, the features of the transport of volatile pollutants at the air-water interface were determined. The results show that the anisotropic coupling diffusion model is more accurate than the isotropic coupling diffusion model and non-coupling diffusion model. Mass transfer significantly increases with the increase of the air-water relative velocity at a low relative velocity. However, at a higher relative velocity, an increase in the relative velocity has no effect on mass transfer.

关键词： volatile pollutant," interfacial mass transfer anisotropic diffusion STDS anisotropic coupling diffusion model

Application of Rietveld Refinement to Investigate the High Chromium White Cast Iron Austempered at Different Temperatures

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Journal of Iron and Steel Research International 2009年第4期16卷 33-38页

作者： HOU Qing-yu HUANG Zhen-yi WANG jing-tao School of Materials Science and Engineering Nanjing University of Science and Technology Nanjing 210094Jiangsu China School of Materials Science and Engineering Anhui University of TechnologyMa'anshan 243002 Anhui China

The effect of austempering temperature on the microstructure and properties of a high chromium white cast iron was investigated with the Rietveld refinement method. The result shows that the upper bainite exists in the sampie austempered at 623 K and the martensite, lower bainite, M7C3, and retained austenite exist in the samples austempered at 563 K and 593 K. The relative content of the retained austenite increases with increasing the austemper- ing temperature from 563 K to 623 K. The higher hardness, impact toughness and impact abrasive wear resistance can be obtained for the specimen austempered at 593 K.

关键词： high chromium white cast iron austempering retained austenite Rietveld refinement~ microstructurelproperties

Electronic structure and optical properties of non-metallic modified graphene:a first-principles study

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Communications in Theoretical Physics 2022年第3期74卷 70-76页

作者： jing-tao Huang Yong Liu Zhong-hong Lai Jin Hu Fei Zhou jing-chuan Zhu School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China Center for analysis measurement and computingHarbin Institute of TechnologyHarbin 150001China MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150001China

In this paper,the electronic structure and stability of the intrinsic,B-,N-,Si-,S-doped graphene are studied based on first-principles calculations of density functional ***,the intrinsic,B-,N-,Si-,S-doped graphene structures are optimized,and then the forming energy,band structure,density of states,differential charge density are analyzed and *** results show that Band Si-doped systems are p-type doping,while N is n-type *** comparing the forming energy,it is found that N atoms are more easily doped in *** addition,for B-,N-,Si-doped systems,it is found that the doping atoms will open the band gap,leading to a great change in the band structure of the doping ***,we systematically study the optical properties of the different *** comparison,it is found that the order of light sensitivity in the visible region is as follows:S-doped>Si-doped>pure>B-doped>*** results will provide theoretical guidance for the stability and electronic structure of non-metallic doped graphene.

关键词： Graphene Non-metallic Electronic structure Optical properties Density functional theory

Design Optimization of Irregular Cellular Structure for Additive Manufacturing

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Chinese Journal of Mechanical Engineering 2017年第5期30卷 1184-1192页

作者： Guo-Hua Song Shi-Kai jing Fang-Lei Zhao Ye-Dong Wang Hao Xing jing-tao Zhou School of Mechanical Engineering Beijing Institute of Technology Key Lab of Contemporary Design and Integrated Manufacturing Technology Ministry of EducationNorthwestern Polytechnical University

Irregularcellular structurehas great potential to be considered in light-weight design field. However, the research on optimizing irregular cellular structures has not yet been reporteddue to the difficulties in their modeling technology. Based on the variable density topology opti- mization theory, an efficient method for optimizing the topology of irregular cellular structures fabricated through additive manufacturing processes is proposed. The pro- posed method utilizes tangent circles to automatically generate the main outline of irregular cellular structure. The topological layoutof each cellstructure is optimized using the relative density informationobtained from the proposed modified SIMP method. A mapping relationship between cell structure and relative densityelement is builtto determine the diameter of each cell structure. The results show that the irregular cellular structure can be optimized with the proposed method. The results of simulation and experimental test are similar for irregular cellular structure, which indicate that the maximum deformation value obtained using the modified Solid Isotropic Microstructures with Penalization （SIMP） approach is lower 5.4× 10-5 mm than that using the SIMP approach under the same under the same external load. The proposed research provides the instruction to design the other irregular cellular structure.

关键词： Irregular cellular structure Additivemanufacturing Topology optimization Relative densitymapping

Establishing Public Crisis Management System in Chinese Minority Regions

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Establishing Public Crisis Management System in Chinese Mino...

Performance Analysis of Anti-Interference Wireless Packet Networks for LEO Micro-Satellite with Adaptive Nulling Antenna Array

2012年公共管理国际会议

作者： GUO jing-tao College of Public Administration of Huazhong University of Science and Technology School of Public Management of Inner Mongolia University

ISBN: (纸本)9787564710316

Currently, the local governments in Chinese minority regions face very serious public security problems. Chinese governors have to pay close attention to the work concerning emergency management. Due to current situation and particularities of public crisis management in regions of minorities, the relevant governments will face greater challenges when managing crisis. The construction of the Chinese e-government not only has a huge influence on the crisis management system, but also provides a convenient platform for the government on the technical implementation. For the regional government crisis managers, they should know how to make full use of existing computer network on e-government platform. The crisis management system in line with the particularities of government crisis management in Chinese minority regions should be built so as to administrate and control the whole process of crisis prevention and governance effectively.

关键词： E-government Regions of minorities Public crisis Emergency management

来源： cnki会议评论

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The Journal of China Universities of Posts and Telecommunications 2006年第2期13卷 10-14页

作者： LIU Hai-tao HAN Fang-jing WAN Jian-wei School DSP Group of National University of Defense Technology Changsha 410073 P.R. China

Information integrity is key to successful operations in intricacy environments in the future, especially when strong interferences exist. This paper presents the design of a novel wireless packet network receiver system for Low Earth Orbit （LEO） micro-satellites with adaptive nulling antenna arrays. It uses three types of interference suppression in cascade： namely spread spectrum, adaptive array nulling, and transform domain filtering. This paper proposes a pilot channel-aided method in order to make full advantage of this arrangement, and analyzes its throughput and delay performance using the Markov chain model. Our results show that this method can achieve excellent delay and throughput performance： When the number of array antenna is 8, its throughput increase relative to the standard Slot-ALOHA protocol is 125 96.

关键词： LEO adaptive array ALOHA packet radio networks