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Ultrafine red phosphorus confined in reasonably designed pitch-based carbon matrix built of well-interconnected carbon nanosheets for high-performance lithium and potassium storage

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Resources Chemicals and Materials 2024年第1期3卷 54-61页

作者： Chang liu Junjun Yao Ying Sun Yaming Zhu hongmei li Daming Feng Hui li Yunlei Yang Quanxing Mao Tianyi Ma Institute of Clean Energy Chemistry Key Laboratory for Green Synthesis and Preparative Chemistry of Advanced Materials of Liaoning ProvinceCollege of ChemistryLiaoning UniversityShenyang 110036China School of Science RMIT UniversityMelbourneVIC 3000Australia Institute of Chemical Engineering University of Science and TechnologyLiaoningAnshan 114051China College of Materials Science and Engineering Shenyang Aerospace UniversityShenyang 110136China

Red phosphorus has been well-recognized as promising anode materials for lithium-ion batteries(liBs)and potassium-ion batteries(PIBs)due to its extremely high theoretical capacity and low ***,the huge volume change and poor electric conductivity severely limit its further practical ***,the nanoscale ultrafine red phosphorus has been successfully confined in a three-dimensional pitch-based porous carbon skeleton composed of well-interconnected carbon nanosheets through the vaporization-condensation *** for the traditional requirement of high electric conductivity and stable mechanical stability,the micropores and small mesopores in the porous carbon matrix centered at 1 to 3 nm and the abundant amount of oxygen-containing functional groups are also beneficial for the high loading and dispersion of red *** anode for liBs,the composite exhibits high reversible discharge capacities of 968 mAh g^(-1),excellent rate capabilities of 593 mAh g^(-1)at 2 A g^(-1),and long cycle performance of 557 mAh g^(-1)at 2 A g^(-1).More impressively,as the anode for PIBs,the composite presents a high reversible capacity of 661 mAh g^(-1)and a stable capacity of 312 mAh g^(-1)at 0.5 A g^(-1)for 500 cycles with a capacity retention up to 84.3%.This work not only sheds light on the structure design of carbon hosts with specific pore structure but also open an avenue for high value-added utilization of coal tar pitch.

关键词： Carbon anodes Coal tar pitch lithium-ion batteries Potassium-ion batteries Red phosphorus

Gas diffusion in catalyst layer of flow cell for CO_(2) electroreduction toward C_(2+) products

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Nano Research 2024年第3期17卷 1101-1106页

作者： Xiqing Wang Qin Chen Yajiao Zhou Yao Tan Ye Wang hongmei li Yu Chen Mahmoud Sayed Ramadan A.Geioushy Nageh K.Allam Junwei Fu Yifei Sun Min liu Hunan Joint International Research Center for Carbon Dioxide Resource Utilization School of Physics and ElectronicsCentral South UniversityChangsha 410083China School of Energy and Power Engineering Beihang UniversityBeijing 100191China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450002China Central Metallurgical Research and Development Institute(CMRDI) P.O.Box 87Helwan 11421CairoEgypt Energy Materials Laboratory School of Sciences and EngineeringThe American University in CairoNew Cairo 11835Egypt Research Center for Advanced Energy and Carbon Neutrality Beihang UniversityBeijing 100191China

The use of gas diffusion electrode(GDE)based flow cell can realize industrial-scale CO_(2) reduction reactions(CO_(2)RRs).Controlling local CO_(2) and CO intermediate diffusion plays a key role in CO_(2)RR toward multi-carbon(C_(2+))*** this work,local CO_(2) and CO intermediate diffusion through the catalyst layer(CL)was investigated for improving CO_(2)RR toward C_(2+)*** gas permeability tests and finite element simulation results indicated CL can balance the CO_(2) gas diffusion and residence time of the CO intermediate,leading to a sufficient CO concentration with a suitable CO_(2)/H_(2)O supply for high C_(2+)*** a result,an excellent selectivity of C_(2+)products~79%at a high current density of 400 mA·cm^(-2) could be obtained on the optimal 500 nm Cu CL(Cu500).This work provides a new insight into the optimization of CO_(2)/H_(2)O supply and local CO concentration by controlling CL for C_(2+)products in CO_(2)RR flow cell.

关键词： gas diffusion electrode CO_(2)reduction Cu mass transfer C_(2)product

Effects of nugget alloying on microstructures and properties of resistance spot welded joints of aluminum and steel

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China Welding 2016年第3期25卷 36-41页

作者： Zhang Yueying Sun Daqian li hongmei Gu Xiaoyan liu Yanjun Key Laboratory of Automobile Materials School of Materials Science and Engineering Jilin University Changchun 130025 SAIC Motor Technology Center Shanghai 201804.

The resistance spot welding of 6063-T6 aluminum alloy and 16Mn steel was studied by nugget alloying. The results indicated that the Al-steel joint had characteristics of welding-brazing. The nugget zone consisted mainly of α-Al solid solution with dislocations and fine Mg2Si particles. The interface zone had a double-layer structure： Fe2Al5 layer at steel side and Fe4Al13 layer at Al nugget side. The nugget alloying has a significant effect on the joint properties by changing phase composition and refinement of grains. When alloy elements Cu, Zn, Ti and Ni were added, the tensile shear load of Al-steel joints reached 2 780 N, 2 910 N, 2 915 N and 2 929 N respectively, which increased by 24. 1%, 29.9%, 30. 1% and 30. 7% respectively compared with that （2 241 N） of joint without nugget alloying. Therefore, it is an effective way for improving mechanical properties of resistance spot welded Al-steel joints.

关键词： 6063-T6 aluminum alloy 16Mn steel resistance spot welding nugget alloying

Evaluation of the Seventh Report of the joint National Committee（JNC 7） and the Suggestion of the Chinese Hypertention Classification （ Gao＇ s Classification）

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美国中华健康卫生杂志 2005年第4期8卷 72-74页

作者： GAO Qun WEI Guo li hongmei The PLA 323 Hospital Cardiovascular Internal Medicine Xi ＇ an 710054 China

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具有先验知识的Q学习算法在AGC中的应用

电力系统自动化 2008年第23期32卷 36-40,99页

作者：李红梅严正上海交通大学电子信息与电气工程学院上海市200240

传统的自动发电控制(AGC)系统通常基于经典的线性控制理论,并且大部分二次调频采用比例积分(PI)控制器,但系统固有的非线性以及结构多变使得积分增益系数不易确定,容易造成超调或调节不足的问题,从而影响系统频率稳定。文中采用强化学... 详细信息

传统的自动发电控制(AGC)系统通常基于经典的线性控制理论,并且大部分二次调频采用比例积分(PI)控制器,但系统固有的非线性以及结构多变使得积分增益系数不易确定,容易造成超调或调节不足的问题,从而影响系统频率稳定。文中采用强化学习控制器代替传统的PI调节器,将考虑了死区、出力约束、机组爬坡率和时延等非线性环节的AGC系统离散化成Markov链,直接将区域控制误差作为系统状态量,并充分利用AGC环境中的已有信息,结合模糊综合决策方法,获得能够改善Q学习效率的先验知识,采用Q学习算法对其进行学习得出离散的AGC策略。数值仿真的结果验证在非线性AGC系统中应用具有先验知识的Q学习方法可以加快收敛速度,提高学习效率,并通过控制性能评价标准(CPS)进一步检验了该方法的可行性。

关键词：自动发电控制积分增益系数 Q学习先验知识模糊综合决策

安全玻璃专用聚乙烯醇缩丁醛膜片加工助剂研究进展

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高分子材料科学与工程 2014年第9期30卷 177-182页

作者：刘荣李红梅成都大学医护学院成都大学生物产业学院四川成都610106

通过助剂调控,开发性能优越的安全玻璃专用聚乙烯醇缩丁醛膜片,已成为一个研究热点。文中介绍了安全玻璃专用聚乙烯醇缩丁醛膜片加工方面的3类助剂——增塑剂、黏度控制剂和稳定剂的最新研究进展。详细介绍了增塑剂中的脂肪族二元酸酯... 详细信息

通过助剂调控,开发性能优越的安全玻璃专用聚乙烯醇缩丁醛膜片,已成为一个研究热点。文中介绍了安全玻璃专用聚乙烯醇缩丁醛膜片加工方面的3类助剂——增塑剂、黏度控制剂和稳定剂的最新研究进展。详细介绍了增塑剂中的脂肪族二元酸酯、邻苯二甲酸酯、多元醇酯和磷酸酯类增塑剂,黏度控制剂中的碱金属和碱土金属化合物、树脂酸盐和四级铵盐黏度控制剂及稳定剂中的热稳定剂和光稳定剂的选用规则、用量及对聚乙烯醇缩丁醛性能的影响。最后,对助剂发展趋势作了展望。

关键词：聚乙烯醇缩丁醛膜片增塑剂黏度控制剂稳定剂研究进展

面装式永磁同步电机驱动系统无位置传感器控制

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电工技术学报 2016年第A01期31卷 85-91页

作者：李红梅王萍合肥工业大学电气与自动化工程学院合肥230009

为了实现面装式永磁同步电机(SMPMSM)驱动系统的无位置传感器运行或位置传感器故障下的系统自适应容错运行,首先介绍基于微分代数的SMPMSM驱动系统转子位置和转速的获取方法,其次研究逆变器死区效应对转子位置估计精度的影响,给出基于... 详细信息

为了实现面装式永磁同步电机(SMPMSM)驱动系统的无位置传感器运行或位置传感器故障下的系统自适应容错运行,首先介绍基于微分代数的SMPMSM驱动系统转子位置和转速的获取方法,其次研究逆变器死区效应对转子位置估计精度的影响,给出基于纹波电流计算的逆变器死区补偿方案,提出基于微分代数且集成逆变器死区补偿的SMPMSM驱动系统无位置传感器控制方案,进而架构无位置传感器控制的SMPMSM驱动系统。通过系统建模、仿真和实验测试验证了所提出的SMPMSM驱动系统无位置传感器控制方案的合理性和有效性。

关键词：面装式永磁同步电机驱动系统微分代数无位置传感器控制纹波电流计算死区补偿

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响应面优化绿色产色链霉菌发酵产阿维拉霉素

中国食品学报 2017年第9期17卷 108-115页

作者：李红梅陈敏浙江工商大学食品与生物工程学院杭州310018 杭州睿岂生物科技有限公司杭州310018

对绿色产色链霉菌生产阿维拉霉素的发酵条件进行优化。在单因素试验的基础上,用Plackett-Burman试验设计筛选影响阿维拉霉素发酵的重要参数。先采用最陡爬坡试验逼近阿维拉霉素最大生产区域,再利用Box-Behnken设计确定重要参数的最佳水... 详细信息

对绿色产色链霉菌生产阿维拉霉素的发酵条件进行优化。在单因素试验的基础上,用Plackett-Burman试验设计筛选影响阿维拉霉素发酵的重要参数。先采用最陡爬坡试验逼近阿维拉霉素最大生产区域,再利用Box-Behnken设计确定重要参数的最佳水平。试验结果表明:油酸添加量、油酸添加时间、培养基初始p H值对阿维拉霉素的合成影响显著。通过响应面分析得到一元二阶方程,对方程求解得到优化的参数值,即油酸添加量0.43%,添加时间71.28 h,培养基初始p H 6.98。在该参数值下进行阿维拉霉素发酵,阿维拉霉素产量达1 207.76μg/m L,较对照提高了109.97%,与模型预测值差异不显著,说明建立的模型是有效的。

关键词：油酸氧载体阿维拉霉素响应面

Current status and reflection on the development of high-speed maglev transportation

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Railway Sciences 2023年第3期2卷 327-335页

作者： hongmei li Junling Shi Xiangdong li Junbo Zhang Yunlong Chen Railway Science and Technology Research and Development Center China Academy of Railway Sciences Corporation LimitedBeijingChina China Academy of Railway Sciences Corporation limited Institute of Scientific and Technical InformationBeijingChina INMAI Railway Technology Co. Ltd.China Academy of Railway Sciences Corporation LimitedBeijingChina College of Mechanical and Electrical Engineering Qingdao UniversityQingdaoChina

Purpose–High-speed maglev technology can address the issues of adhesion,friction,vibration and highspeed current collection in traditional wheel-rail systems,making it an important direction for the future development of high-speed rail ***/methodology/approach–This paper elaborates on the demand and significance of developing high-speed maglev technology worldwide and examines the current status and technological maturity of several major high-speed maglev systems ***–This paper summarizes the challenges in the development of high-speed maglev railways in *** on this analysis,it puts forward considerations for future research on high-speed maglev ***/value–This paper describes the development status and technical maturity of several major high-speed maglev systems in the world for the first time,summarizes the existing problems in the development of China’s high-speed maglev railway and on this basis,puts forward the thinking of the next research of China’s high-speed maglev railway.

关键词： High-speed maglev Necessity Current development status Problems in development Reflections