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Surface Doping vs.Bulk Doping of Cathode Materials for Lithium-Ion Batteries:A Review

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Electrochemical Energy Reviews 2022年第4期5卷 254-285页

作者： Huaming Qian Haoqi Ren Ying Zhang xianfeng he Wenbin Li Jingjing Wang Junhua Hu Hong Yang Hirbod Maleki Kheimeh Sari Yu Chen Xifei Li Xi’an Key Laboratory of New Energy Materials and Devices Institute of Advanced Electrochemical Energy and School of Materials Science and EngineeringXi’an University of TechnologyXi’an 710048ShaanxiChina Shaanxi International Joint Research Center of Surface Technology for Energy Storage Materials Xi’an 710048ShaanxiChina Department of Mechanical and Materials Engineering University of Western OntarioLondonOntario N6A 5B9Canada State Center for International Cooperation On Designer Low‑Carbon and Environmental Materials(CDLCEM) Zhengzhou University100 Kexue AvenueZhengzhou 450001China Xi’an Safty Energy Technology Co. LtdXi’an 710005ShaanxiChina

To address the capacity degradation,voltage fading,structural instability and adverse interface reactions in cathode materi-als of lithium-ion batteries(LIBs),numerous modification strategies have been developed,mainly including coating and doping.In particular,the important strategy of doping(surface doping and bulk doping)has been considered an effective strategy to modulate the crystal lattice structure of cathode materials.However,special insights into the mechanisms and effectiveness of the doping strategy,especially comparisons between surface doping and bulk doping in cathode materials,are still lacking.In this review,recent significant progress in surface doping and bulk doping strategies is demonstrated in detail by focusing on their inherent differences as well as effects on the structural stability,lithium-ion(Li-ion)diffusion and electrochemical properties of cathode materials from the following mechanistic insights:preventing the exposure of reactive Ni on the surface,stabilizing the Li slabs,mitigating the migration of transition metal(TM)ions,alleviating unde-sired structural transformations and adverse interface issues,enlarging the Li interslab spacing,forming three-dimensional(3D)Li-ion diffusion channels,and providing more active sites for the charge-transfer process.Moreover,insights into the correlation between the mechanisms of hybrid surface engineering strategies(doping and coating)and their influences on the electrochemical performance of cathode materials are provided by emphasizing the stabilization of the Li slabs,the enhancement of the surface chemical stability,and the alleviation of TM ion migration.Furthermore,the existing challenges and future perspectives in this promising field are indicated.

关键词： Lithium-ion batteries Cathode materials Surface doping Bulk doping Hybrid surface engineering Structural stability Lithium-ion diffusion

夏热冬冷地区地板辐射和风机盘管供暖的对比分析

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流体测量与控制 2024年第2期5卷 41-46,50页

作者：何险峰上海电子工程设计研究院有限公司上海200083

为分析地板辐射供暖和风机盘管供暖在夏热冬冷地区的具体运行效果,对两种模式下的室内热舒适、供热能力和能耗进行了实验和OpenStudio模拟分析。实验和模拟结果表明:风机盘管系统在运行初期体现优势,但后期地板辐射供暖具有更好的室内... 详细信息

为分析地板辐射供暖和风机盘管供暖在夏热冬冷地区的具体运行效果,对两种模式下的室内热舒适、供热能力和能耗进行了实验和OpenStudio模拟分析。实验和模拟结果表明:风机盘管系统在运行初期体现优势,但后期地板辐射供暖具有更好的室内舒适性,垂直峰谷差仅为0.03℃,预测平均值模型PMV为-0.28,预测不满意百分比指标(PPD)为6.83%;地板辐射供热能力大于风机盘管供热,且耗电量更低。

关键词：地板辐射供暖风机盘管热舒适性供热能力 OpenStudio

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基于多重遗传算法的中央空调能效优化

流体测量与控制 2024年第1期5卷 14-18,22页

作者：何险峰上海电子工程设计研究院有限公司上海200083

为提高中央空调制冷系统能效比,实现不同工况下最优能效比,提出一种基于多重遗传算法的中央空调制冷系统能效优化方法。该方法通过灰色关联度分析(GRA)筛选出对中央空调能效比影响较大的关键运行参数,利用神经网络建立关键运行参数与能... 详细信息

为提高中央空调制冷系统能效比,实现不同工况下最优能效比,提出一种基于多重遗传算法的中央空调制冷系统能效优化方法。该方法通过灰色关联度分析(GRA)筛选出对中央空调能效比影响较大的关键运行参数,利用神经网络建立关键运行参数与能效比间的能效预测模型,通过Apriori关联规则算法获取关键运行参数间的关联规则,将预测模型作为多重遗传算法的适应度函数,关联规则作为遗传算法种群进化的约束条件。分别采用多重遗传算法和传统遗传算法进行能效比优化,结果表明,多重遗传算法比传统遗传算法能效比平均提高了5.75%,优化效果明显。

关键词：中央空调能效优化关联规则多重遗传算法

International Students’Acculturation in China

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Journal of Contemporary Educational Research 2021年第11期5卷 178-182页

作者： xianfeng he China Star Limited For International Economic&Technical Cooperation Beijing 100026China

With the development of globalization,more and more international students are pursuing their studies in China.The adjustment issues faced by these students should be explored in order to ensure the students’successful transition to the host country.This study aims at exploring the cultural adaptation of international students studying in China and their interests in the Chinese culture.

关键词： International students Acculturation Chinese language Chinese culture Intercultural communication

Quasi-real-time simulation of rotating drum using discrete element method with parallel GPU computing

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Particuology 2011年第4期9卷 446-450页

作者： Ji Xu Huabiao Oi Xiaojian Fang Liqiang Lu Wei Ge Xiaowei Wang Ming xu Feiguo Chen xianfeng he Jinghai Li State Key Laboratory of Multiphase Complex Systems Institute of Process Engineering (IPE) Chinese Academy of Sciences. P.O. Box 353 Beijing 100190 China Graduate University of the Chinese Academy of Sciences Beijing 100039 China

Real-time simulation of industrial equipment is a huge challenge nowadays. The high performance and fine-grained parallel computing provided by graphics processing units （GPUs） bring us closer to our goals. In this article, an industrial-scale rotating drum is simulated using simplified discrete element method （DEM） without consideration of the tangential components of contact force and particle rotation. A single GPU is used first to simulate a small model system with about 8000 particles in real-time, and the simulation is then scaled up to industrial scale using more than 200 GPUs in a 1 D domain-decomposition parallelization mode. The overall speed is about 1/11 of the real-time. Optimization of the communication part of the parallel GPU codes can speed up the simulation further, indicating that such real-time simulations have not only methodological but also industrial implications in the near future.

关键词： Rotating drumReal-time Discrete element method （DEM） Speedup GPU

不同粉煤灰掺量下SCC单轴压缩试验离散元数值分析

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人民黄河 2024年第7期46卷 143-147页

作者：程学磊王亚佐刘俊霞郑锦辉海然何鲜峰中原工学院建筑工程学院河南郑州450007 黄河水利委员会黄河水利科学研究院河南郑州450003

为了研究不同粉煤灰掺量自密实混凝土的力学性能变化及破坏性状,利用PFC2D中的FISH语言及该程序自带的线性黏结模型,建立不同粉煤灰掺量自密实混凝土单轴压缩试验离散元模型,并与实际试验结果进行对比,分析其内部破坏形态与力链变化。... 详细信息

为了研究不同粉煤灰掺量自密实混凝土的力学性能变化及破坏性状,利用PFC2D中的FISH语言及该程序自带的线性黏结模型,建立不同粉煤灰掺量自密实混凝土单轴压缩试验离散元模型,并与实际试验结果进行对比,分析其内部破坏形态与力链变化。研究表明:不同粉煤灰掺量FA-SCC的极限强度呈先增后减的趋势,破坏裂缝均为对角裂缝,区别在于中部竖向裂纹数量不同,建立的二维离散元数值模型可以很好地模拟粉煤灰自密实混凝土结构轴压破坏时材料内部微裂纹产生、裂缝扩展及对角贯通裂缝形成的过程,弥补了室内试验仅仅依靠肉眼观测的不足,同时模型输出的不同粉煤灰掺量自密实混凝土的轴压强度及应力应变曲线与实验室试验结果高度贴合,最大抗压强度误差不超过7.1%。

关键词：自密实混凝土粉煤灰单轴压缩离散元分析

维生素D缺乏对新生儿血糖血脂、炎症指标和生长发育的影响研究

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中国妇幼健康研究 2024年第6期35卷 64-68页

作者：薛丹陈佳何先凤杨进宇余静电子科技大学医学院附属绵阳医院/绵阳市中心医院儿科四川绵阳621000

目的探究维生素D缺乏对新生儿血糖和血脂水平、炎症指标及生长发育的影响。方法选取2020年3月至2022年12月于绵阳市中心医院就诊的孕中后期维生素D缺乏的96例孕妇为观察组,选取同期在本院接受检查的孕中后期维生素D水平正常的80例孕妇... 详细信息

目的探究维生素D缺乏对新生儿血糖和血脂水平、炎症指标及生长发育的影响。方法选取2020年3月至2022年12月于绵阳市中心医院就诊的孕中后期维生素D缺乏的96例孕妇为观察组,选取同期在本院接受检查的孕中后期维生素D水平正常的80例孕妇为对照组,跟踪至两组孕妇正常分娩。对比两组新生儿的空腹血糖(FPG)、血清总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)、血清白细胞介素-6(IL-6)、超敏C反应蛋白(hs-CRP)水平,测量新生儿的出生体质量、身长、头围、Ponderal指数(PI),分析维生素D缺乏对新生儿血糖血脂、炎症指标和生长发育的影响。结果观察组新生儿FPG、TC、LDL-C水平均高于对照组,差异有统计学意义(t值分别为3.228、3.210、2.414,P0.05);观察组新生儿的hs-CRP、IL-6水平均高于对照组,差异有统计学意义(t值分别为9.816、5.554,P0.05)。结论孕期母体维生素D缺乏可能引起新生儿血糖和血脂浓度水平升高,影响炎症指标和新生儿的体质量、身长,因此孕期维生素D缺乏时应注意适当补充。

关键词：维生素D 新生儿血糖和血脂炎症指标生长发育

Masting promotes transformation from predation to mutualism in an oak-weevil-rodent system

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Science China(Life Sciences) 2024年第7期67卷 1514-1524页

作者： Hongmao Zhang Hongyu Niu Michael ASteele Liqing Peng Huimin he Aoqiang Li xianfeng Yi Hongjun Li Zhibin Zhang Institute of Evolution and Ecology School of Life SciencesCentral China Normal UniversityWuhan 430079China State Key Laboratory of Integrated Management of Pest Insects and Rodents in Agriculture Institute of ZoologyChinese Academy of SciencesBeijing 100101China Department of Biology Wilkes UniversityWilkes-Barre 18766USA School of Life Sciences Qufu Normal UniversityQufu 273165China

The significance of ecological non-monotonicity(a function whose first derivative changes signs)in shaping the structure and functions of the ecosystem has recently been recognized,but such studies involving high-order interactions are rare.here,we have proposed a threetrophic conceptual diagram on interactions among trees,rodents,and insects in mast and non-mast years and tested the hypothesis that oak(Quercus wutaishanica)masting could result in increased mutualism and less predation in an oak-weevil-rodent system in a warm temperate forest of China.Our 14-year dataset revealed that mast years coincided with a relatively low rodent abundance but a high weevil abundance.Masting not only benefited seedling recruitment of oaks through increased dispersal by rodents but also a decrease in predation by rodents and weevils,as well as an increase in the overwintering survival of rodents.Masting appeared to have increased weevil survival by reducing predation of infested acorns by rodents.These results suggest that masting benefits all participants in the plant-insect-rodent system by increasing mutualism and reducing predation behavior(i.e.,a non-monotonic function).Our study highlights the significance of masting in maintaining the diversity and function of the forest ecosystem by facilitating the transformation from predation to mutualism among trophic species.

关键词： antagonism ecological non-monotonicity mutualism seed-weevil-rodent system seedling recruitment rodent overwintering survival weevil survival

Perspective of alkaline zinc-based flow batteries

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Science China Chemistry 2024年第1期67卷 260-275页

作者： Zhizhang Yuan xianfeng Li Division of Energy Storage Dalian National Laboratory for Clean Energy(DNL)Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 110623China

Energy storage technologies have been identified as the key in constructing new electric power systems and achieving carbon neutrality,as they can absorb and smooth the renewables-generated electricity.Alkaline zinc-based flow batteries are well suitable for stationary energy storage applications,since they feature the advantages of high safety,high cell voltage and low cost.Currently,many alkaline zinc-based flow batteries have been proposed and developed,e.g.,the alkaline zinc–iron flow battery and alkaline zinc–nickel flow battery.Their development and application are closely related to advanced materials and battery configurations.In this perspective,we will first provide a brief introduction and discussion of alkaline zinc-based flow batteries.Then we focus on these batteries from the perspective of their current status,challenges and prospects.The bottlenecks for these batteries are briefly analyzed.Combined with the practical requirements and development trends of alkaline zinc-based flow battery technologies,their future development and research direction will be summarized.

关键词： energy storage alkaline zinc-based flow batteries advanced materials battery structure