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Synergistic Effects of Carbon Nanotube(CNT)and Reduced Graphene Oxide(RGO)on Mechanical and Thermal Properties of ZK61 Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 577-585页

作者： Fanjing Meng Wenbo Du ning ding Jian Sun Xian Du Ke Liu Shubo Li College of Materials Science and Engineering Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China

The hybrid of carbon nanotube(CNT)and reduced graphene oxide(RGO)reinforced ZK61 composite was fabricated by a hot extrusion process.Compared with the raw ZK61 alloy and single-reinforced composites,the hybrid-reinforced by RGO+CNT complex exhibited significant enhancements both in mechanical and thermal performance.By adjusting the proportion of RGO and CNT in ZK61 alloy,the obtained optimum ZK61/(0.06 wt%RGO+0.54 wt%CNT)composite exhibited increase of 25.4%in yield strength,26.5%in ultimate tensile strength,104%in failure strain and 30.4%in thermal conductivity,respectively,in comparison with ZK61 alloy.The superior properties of the nano-hybrid composite are attributed to the synergetic effects of RGO and CNT,leading to a uniform dispersion and integrated structure as well as the enhanced interfacial bonding with matrix.The strengthening ability of RGO and CNT was calculated to quantify their individual contribution to the improvement in mechanical and thermal properties of the ZK61 matrix composite.The RGO+CNT hybrids provide a promising way to develop Mg matrix composites with impressive performances.

关键词： Mg matrix composite Carbon nanotube Reduced graphene oxide Mechanical performance Thermal conductivity

Chiral multiple-resonance thermally activated delayed fluorescence materials based on chiral spiro-axis skeleton for efficient circularly polarized electroluminescence

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Science China Chemistry 2024年第7期67卷 2257-2264页

作者： Shi-Quan Song Xiao Han Zhong-Zhong Huo Ching-Fai Yip Xian-Fang Hong Meng-ning ding You-Xuan Zheng State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Key Laboratory of Mesoscopic Chemistry of Ministry of Education School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Chiral luminescence materials have potential applications in the field of three-dimensional displays due to their circularly polarized luminescence(CPL)characteristics.However,the further development of circularly polarized organic light-emitting diodes(CP-OLEDs)needs to meet the requirements of high efficiency,high color purity,low cost,and high dissymmetry factor(gPLor gEL),chiral multiple resonance thermally activated delayed fluorescence(MR-TADF)materials are considered as candidates in these aspects.Herein,based on a pair of chiral spirofluorene precursors,two pairs of high-performance chiral MR-TADF emitters((R/S)-p-Spiro-DtBuCzB and(R/S)-m-Spiro-DtBuCzB)are developed,which exhibit strong emissions peaking at 491 and 502 nm in toluene with full-width at half-maximum values of 25 and 33 nm,respectively.In addition,small singlet–triplet energy gaps of 0.15 and 0.10 eV with high absolute photoluminescence efficiencies of 95.0%and 96.7%are observed for p-Spiro-DtBuCzB and m-Spiro-DtBuCzB molecules,respectively.OLEDs based on p-Spiro-DtBuCzB and m-Spiro-DtBuCzB display high maximum external quantum efficiencies of 29.6%and 33.8%,respectively.Most importantly,CP-OLEDs present symmetric circularly polarized electroluminescence spectra with|gEL|factors of 3.36×10^(-4)and 7.66×10^(-4)for devices based on(R/S)-p-Spiro-DtBuCzB and(R/S)-m-Spiro-DtBuCzB enantiomers,respectively.

关键词： chiral spiro-axis skeleton-based material multiple resonance thermally activated delayed fluorescence circularly polarized electroluminescence dissymmetry factor external quantum efficiency

Photovoltaic,thermoelectric and electromagnetic generation technologies applied in power systems for mobile unmanned systems

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Science China(Technological Sciences) 2023年第3期66卷 599-629页

作者： ding ning WANG XiangYang XIAN XiaoYang CAI YeYun LIU DaoMing DENG Fang Key Laboratory of Intelligent Control and Decision of Complex Systems School of AutomationBeijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China

Unmanned systems are increasingly adopted in various fields,becoming an indispensable technology in daily life.Power systems are the lifeblood of unmanned systems,and affect the working time and task complexity.However,traditional power systems,such as batteries and fuels have a fixed capacity.Therefore,once the power supply is exhausted and cannot be replenished in time,the unmanned systems will stop working.Hence,researchers have increasingly begun paying attention to renewable energy generation technologies.The principles,advantages,and limitations of renewable energy generation technologies are different,and their application effects in different unmanned systems are also uneven.This paper presents a comprehensive study of the application and development status of photovoltaic,thermoelectric,and magnetoelectric generation technologies in four kinds of unmanned systems,including space,aviation,ground,and water,and then summarizes the adaptability and limitations of the three technologies to different systems.Moreover,future development directions are predicted to enhance the reliability of renewable energy generation technologies in unmanned systems.This is the first study to conduct a comprehensive and detailed study of renewable energy generation technologies applied in unmanned systems.The present work is critical for the development of renewable energy generation technologies and power systems for unmanned systems.

关键词： unmanned system renewable energy generation technology photovoltaic generation thermoelectric generation electromagnetic generation

一种适用于深远海全直流风电汇集网络的保护方法

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电力系统保护与控制 2024年第2期52卷 15-25页

作者：丁华星邹贵彬王凤莲丁宁山东大学山东济南250061 国网山东超高压公司山东济南250000

随着海上风电向深远海发展,全直流型风电场由于不存在过电压问题等优点逐渐受到重视。针对全直流海上风电场的汇集线路继电保护问题,首先分析了直流汇集网络在不同故障类型及不同故障位置下的故障特征,计算对应故障情况下的故障电流,并... 详细信息

随着海上风电向深远海发展,全直流型风电场由于不存在过电压问题等优点逐渐受到重视。针对全直流海上风电场的汇集线路继电保护问题,首先分析了直流汇集网络在不同故障类型及不同故障位置下的故障特征,计算对应故障情况下的故障电流,并与仿真值进行对比验证。根据故障特征提出一种利用汇集侧暂态电流变化率的单端量故障选线方案,利用区内外故障的故障暂态电流变化率极性和幅值差异,可在换流器过流闭锁前快速识别故障类型、故障线路及极性。通过在母线处设置附加选线流程,使线路末端高阻接地故障时也能准确选线。在PSCAD/EMTDC平台中搭建了全直流海上风电场模型,进行多种故障场景下的仿真分析,验证了所提故障选线方法的有效性。

关键词：直流海上风电场直流汇集网络故障分析暂态电流变化率故障选线

Laves-Co_(2)(HfTa)合金的相稳定性及热物性

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物理学报 2024年第12期73卷 277-287页

作者：丁宁倪晓东田付阳北京科技大学应用物理研究所北京100083

基于第一性原理计算方法,在考虑磁效应的基础上,对不同温度下合金Co_(2)(HfTa)中的稳定结构、电子性质和热力学性质展开了研究.通过第一性原理计算形成能、弹性性质及声子色散关系,结果表明合金Co_(2)(Hf_(x)Ta_(1-x))在x≤0.75时基态是... 详细信息

基于第一性原理计算方法,在考虑磁效应的基础上,对不同温度下合金Co_(2)(HfTa)中的稳定结构、电子性质和热力学性质展开了研究.通过第一性原理计算形成能、弹性性质及声子色散关系,结果表明合金Co_(2)(Hf_(x)Ta_(1-x))在x≤0.75时基态是C36,当x>0.75时基态是C14.这一发现提示了合金成分对其基态结构的影响,并为合金的稳定性提供了重要线索.值得注意的是,考虑了振动熵和电子熵的贡献后,Co_(2)Hf相对稳定的结构变为C36,Co_(2)Ta变为C14,这表明温度会对合金结构稳定性的影响.Co_(2)(Hf_(x)Ta_(1-x))合金在弹性方面呈现出本征脆性.热力学分析表明其在高温下热容趋于稳定,德拜温度近似为常数,振动熵随温度递增且与压强负相关.电子态密度分析揭示了Co_(2)(HfTa)合金三个结构的相稳定性.

关键词： Co_(2)(HfTa) Laves相稳定性热物性质第一性原理计算

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基于虚拟现实技术的船舶装配工艺仿真优化

舰船科学技术 2024年第7期46卷 171-174页

作者：张莹丁宁河南省智彗教育与智能技术应用工程技术研究中心河南郑州450000

传统依靠人工经验或者试错法的船舶装配不仅耗费大量的时间,同时也会给船舶装配带来极大的不确定性。本文将虚拟现实技术应用于船舶装配中,对船舶装配工艺仿真优化进行相关研究。构建船舶虚拟装配环境,包括虚拟装配建模、装配序列规划... 详细信息

传统依靠人工经验或者试错法的船舶装配不仅耗费大量的时间,同时也会给船舶装配带来极大的不确定性。本文将虚拟现实技术应用于船舶装配中,对船舶装配工艺仿真优化进行相关研究。构建船舶虚拟装配环境,包括虚拟装配建模、装配序列规划、装配路径规划、装配干涉检测、可达性分析以及装配过程仿真。船舶设计数据、装配工艺数据、虚拟环境数据以及人机交互数据为构建船舶虚拟装配工艺优化提供数据基础。使用数字化编号可以优化装配序列规划,采用包围盒法对虚拟模型碰撞检测进行优化,通过对比发现,优化后包围盒在空间上明显大幅减小,降低了不同零件模型之间的碰撞风险。

关键词：虚拟现实装配工艺仿真优化碰撞

Bromodimethylsulfonium Bromide Catalyzed Synthesis of Methyl 2-Dexoy-4,6-O-benzylidene Galactopyranoside from Galactal and the Rapid Route to 2,3- and 2,6-Dideoxygalactopyranoses

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Chinese Journal of Chemistry 2012年第2期30卷 409-412页

作者： ding,ning Chun,Yuexing Zhang,Wei Li,Yingxia Department of Medicinal Chemistry Fudan University826 Zhangheng RoadShanghai 201203China School of Medicine and Pharmacy Ocean University of ChinaQingdaoShandong 266003China

有 2 由 bromodimethylsulfonium 溴化物催化的 PhCH (OCH3 ) 的 D-galactal 的 4,6-O-Benzylidenation 高效地导致甲基 2-dexoy-4,6-O-benzylidene galactopyranoside，它用作关键中介到 2,3-dideoxy 和 2,6-dideoxy galactopyranosid... 详细信息

关键词：半乳糖苷催化合成苄基溴化干线溴甲基中间体 O型

Perturbation to Mei Symmetry and Noether Adiabatic Invariants for Birkhoffian Systems

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Communications in Theoretical Physics 2008年第6期49卷 1410-1412页

作者： ding ning FANG Jian-Hui Department of Physics and Electronics Science Binzhou University Binzhou 256600 China College of Physics Science and Technology China University of Petroleum Dongying 257061 China

基于这个概念断热不变，不安到 Mei 对称和 Noether 为 Birkhoffian 系统的断热的 invariants 被学习。为没有不安的系统的 Mei 对称的准确 invariants 被给。到 Mei 对称的不安被讨论，从不安导致到系统的 Mei 对称的 Noether 断热的 i... 详细信息

基于这个概念断热不变，不安到 Mei 对称和 Noether 为 Birkhoffian 系统的断热的 invariants 被学习。为没有不安的系统的 Mei 对称的准确 invariants 被给。到 Mei 对称的不安被讨论，从不安导致到系统的 Mei 对称的 Noether 断热的 invariants 被获得。

关键词： Mei对称扰动 Noether隔热曲线不变式 Birkhoffian系统

A New Type of Mei Adiabatic Invariant Induced by Perturbation to Mei Symmetry of Hamiltonian Systems

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Communications in Theoretical Physics 2009年第7期52卷 12-16页

Considering full perturbation to infinitesimal generators in the Mei structure equation,a new type of Meiadiabatic invariant induced by perturbation to Mei symmetry for Hamiltonian system was reported.

关键词： Mei对称性绝热不变量哈密顿系统摄动 Hamilton系统诱导结构方程发电机