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Staged dendrite suppression for high safe and stable lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第1期100卷 674-683页

作者： Jun Jiang Zhenjie lu Yanwen Ding Shujun Liu Zhijie Qi Tian Tang Yunfan Zhang Zhiyuan Ma Jingwen Sun Liang Xue Wenyao Zhang pan Xiong Xin Wang Junwu Zhu Yongsheng Fu Key Laboratory for Soft Chemistry and Functional Materials of Ministry of Education Nanjing University of Science and Technology Jiangsu Pylon Battery Co.Ltd

The unavoidable dendrite growth and shuttle effect have long been stranglehold challenges limiting the safety and practicality of lithium-sulfur ***,we propose a dual-action strategy to address the lithium dendrite issue in stages by constructing a multifunctional surface-negatively-charged nanodiamond layer with high ductility and robust puncture resistance on polypropylene （PP） *** uniformly loaded compact negative layer can not only significantly enhance electron transmission efficiency and promote uniform lithium deposition,but also reduce the formation of dendrite during early deposition *** importantly,under the strong puncture stress encountered during the deterioration of lithium dendrite growth under limiting current,the high ductility and robust puncture resistance（145.88 MPa） of as-obtained nanodiamond layer can effectively prevent short circuits caused by unavoidable lithium *** Li||Li symmetrical cells assembled with nanodiamond layer modified PP demonstrated a stable cycle of over 1000 h at 2 mA cm-2with a polarization voltage of only 29.3 ***,the negative charged layer serves as a physical barrier blocking lithium polysulfide ions,effectively mitigating capacity *** improved cells achieved a capacity decay of only 0.042%per cycle after 700 cycles at 3 C,demonstrating effective suppression of dendrite growth and capacity attenuation,showing promising prospect.

关键词： Ductility

前期东北大西洋-地中海西部海温异常影响河南省干热风的可能途径

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高原气象 2025年第1期44卷 150-162页

作者：竹磊磊苏晓乐潘攀吴璐杨婷中国气象局•河南省农业气象保障与应用技术重点开放实验室河南郑州450003 河南省气候中心河南郑州450003

河南省是中国冬小麦的主产区,也是较易受干热风影响的地区。目前对干热风的研究和预报多在天气尺度,从气候的角度研究干热风是否具有可预报性,具有非常重要的意义。本文基于河南省干热风资料、NCEP/NCAR再分析资料和哈得莱环流中心海温... 详细信息

河南省是中国冬小麦的主产区,也是较易受干热风影响的地区。目前对干热风的研究和预报多在天气尺度,从气候的角度研究干热风是否具有可预报性,具有非常重要的意义。本文基于河南省干热风资料、NCEP/NCAR再分析资料和哈得莱环流中心海温资料,分析了1980-2022年前期海温异常与河南省干热风日数的关系,及其可能影响途径。结果表明:(1)豫北、豫西北和豫中多年平均干热风日数较多,其他地区则相对较少。日干热风出现的概率由南向北、由5月下旬至6月上旬逐渐增加。全省平均干热风日数有显著增加趋势。(2)河南省干热风日数与当年3-4月东北大西洋-地中海西部(关键区)海温在年代际和年际尺度上均存在着密切相关,两者与干热风发生时段500 hPa高度场在去趋势前和去趋势后的显著正相关区在东亚中纬度地区位于新疆北部至贝加尔湖尔湖北部,显著负相关区位于我国东北至日本群岛附近,与850 hPa风场在去趋势前和去趋势后的相关在上述正、负显著相关区分别呈反气旋和气旋分布,气旋后部呈偏北风的显著相关,即3-4月关键区高海温年,出现的蒙古高压脊和东亚大槽造成了河南省的干热风天气。海温与环流场的相关在去趋势前和去趋势后在中纬度地区呈现出一个更明显的由东北大西洋经欧亚大陆至东北亚的纬向遥相关波列。(3)西太平洋副热带高压(以下简称副高)偏南(北)时,干热风日数易偏多(少),而3-4月关键区高(低)海温则可以导致副高偏南(北)。(4)干热风偏多年和偏少年、3-4月关键区高海温年和低海温的干热风发生时段30°N-55°N经向平均的涡度差值,及高、低海温年的干热风发生时段500 hPa准地转流函数距平和波作用通量均显示在中纬度地区存在自东北大西洋至东北亚的纬向波列。也即表明,3-4月关键区海温可以激发出一个后期干热风发生时段的类似波列,经欧亚大陆传至东北亚,而高海温年在东亚中纬度地区的环流分布造成了河南省的干热风天气。

关键词：干热风东北大西洋地中海西部海温遥相关波列

考虑场地效应的多点地震动作用下边坡永久位移分析

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岩土工程学报 2025年第1期47卷 65-75页

作者：宋健潘驭航陆朱汐姬建张飞高玉峰河海大学岩土力学与堤坝工程教育部重点实验室江苏南京210024 河海大学土木与交通学院江苏南京210024

地震动引起的边坡土层非线性动力响应可能导致坡体不同位置的地震动加速度时程不一致,从而对整个滑动体的极限平衡状态及之后的地震累积永久位移产生影响。为了研究场地效应对边坡地震永久位移的影响,基于极限平衡条分法,通过对不同土... 详细信息

地震动引起的边坡土层非线性动力响应可能导致坡体不同位置的地震动加速度时程不一致,从而对整个滑动体的极限平衡状态及之后的地震累积永久位移产生影响。为了研究场地效应对边坡地震永久位移的影响,基于极限平衡条分法,通过对不同土条赋予不同的水平和竖向地震动时程,推导出一种考虑场地效应的圆弧和任意形状滑面的多点地震作用下边坡永久位移分析方法。通过与有限差分软件FLAC的数值模拟结果进行对比,验证了该方法能够合理考虑地震动的场地效应。通过研究不同分布形式的多点地震动及竖向地震动对边坡永久位移的影响,结果表明:场地效应引起的水平地震动放大以及多点地震动不同分布模式会导致整个滑体平均地震惯性力作用位置发生改变,从而影响地震作用下滑动体沿滑面的永久变形量,竖向地震动对边坡地震位移影响较小。将方法应用于Lexington土石坝震后变形案例分析,计算得到的坝坡地震永久位移与实际震后观测值相吻合,证明了考虑场地效应的重要性及本文方法的合理性。

关键词：地震边坡稳定性场地效应永久位移极限平衡条分法多点地震动

Monitoring nearest neighbor queries with cache strategies

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第4期8卷 529-537页

作者： pan Peng lu Yan-sheng College of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 China

The problem of continuously monitoring multiple K-nearest neighbor (K-NN) queries with dynamic object and query dataset is valuable for many location-based applications. A practical method is to partition the data space into grid cells, with both object and query table being indexed by this grid structure, while solving the problem by periodically joining cells of objects with queries having their influence regions intersecting the cells. In the worst case, all cells of objects will be accessed once. Object and query cache strategies are proposed to further reduce the I/O cost. With object cache strategy, queries remaining static in current processing cycle seldom need I/O cost, they can be returned quickly. The main I/O cost comes from moving queries, the query cache strategy is used to restrict their search-regions, which uses current results of queries in the main memory buffer. The queries can share not only the accessing of object pages, but also their influence regions. Theoretical analysis of the expected I/O cost is presented, with the I/O cost being about 40% that of the SEA-CNN method in the experiment results.

关键词： K-nearest neighbors (K-NNs) Continuous query Object cache Query cache

Two dimensional(2D) graphdiyne-based nanomaterial for bacterial inactivation

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Progress in Natural Science:Materials International 2023年第6期33卷 780-788页

作者： Chuanqi pan Bohua lu Weihua Li Institute of Chemistry Henan Academy of Sciences High & New Technology Research Center of Henan Academy of Sciences North China University of Water Resources and Electric Power

Infectious diseases caused by pathogenic bacteria and viruses pose a great threat to the ecological environment and the lives and health of humans and animals. Developing efficient bacterial inactivation techniques and nanomaterials prevent the invasion of pathogenic bacteria has become the goal pursued by researchers. Carbon materials exhibit enormous potential for bacterial inactivation applications due to their excellent biocompatibility, environmental friendliness, and high antibacterial performance. Graphdiyne(GDY), as a novel twodimensional carbon material, has attracted widespread attention in the fields of biology and antibacterial due to its unique acetylene bonds, easily tunable electronic structure, good biocompatibility and peroxidase-like properties etc. This review summarizes the research progress of GDY and GDY-based nanomaterials, including pristine GDY, graphdiyne oxide(GDYO), heteroatom doped-GDY, and GDY-based composite materials in the field of bacterial inactivation, and discusses the opportunities and challenges faced by GDY-based nanomaterials in the fields of biomedicine and antibacterial in the future.

关键词： GDY Carbon materials Nanomaterials Acetylene bonds Bacterial inactivation

Extraction technique of region of interest from stereoscopic video

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The Journal of China Universities of Posts and Telecommunications 2017年第5期24卷 68-76页

作者： lu Chaohui pan Jiaying School of Information Engineering Communication University of China Beijing 100024 China

A feature fusion approach is presented to extract the region of interest （ROI） from the stereoscopic video. Based on human vision system （HVS）, the depth feature, the color feature and the motion feature are chosen as vision features. The algorithm is shown as follows. Firstly, color saliency is calculated on superpixel scale. Color space distribution of the superpixel and the color difference between the superpixel and background pixel are used to describe color saliency and color salient region is detected. Then, the classic visual background extractor （Vibe） algorithm is improved from the update interval and update region of background model. The update interval is adjusted according to the image content. The update region is determined through non-obvious movement region and background point detection. So the motion region of stereoscopic video is extracted using improved Vibe algorithm. The depth salient region is detected by selecting the region with the highest gray value. Finally, three regions are fused into final ROI. Experiment results show that the proposed method can extract ROI from stereoscopic video effectively. In order to further verify the proposed method, stereoscopic video coding application is also carried out on the joint model （JM） encoder with different bit allocation in RO｜ and the background region.

关键词： stereoscopic video depth saliency ROI Vibe

Hardware-in-the-loop simulation technology of wide-band radar targets based on scattering center model

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Chinese Journal of Aeronautics 2015年第5期28卷 1476-1484页

作者： Huang Hao pan Minghai lu Zhijun Key Laboratory of Radar Imaging and Microwave Photonics Ministry of Education Nanjing University of Aeronautics and Astronautics Shanghai Key Laboratory of Space Intelligent Control Technology

Hardware-in-the-loop （HWIL） simulation technology can verify and evaluate the radar by simulating the radio frequency environment in an anechoic chamber. The HWIL simulation technology of wide-band radar targets can accurately generate wide-band radar target echo which stands for the radar target scattering characteristics and pulse modulation of radar transmitting signal. This paper analyzes the wide-band radar target scattering properties first. Since the responses of target are composed of many separate scattering centers, the target scattering characteristic is restructured by scattering centers model. Based on the scattering centers model of wide-band radar target, the wide-band radar target echo modeling and the simulation method are discussed. The wide-band radar target echo is reconstructed in real-time by convoluting the transmitting signal to the target scattering parameters. Using the digital radio frequency memory （DRFM） system, the HWIL simulation of wide-band radar target echo with high accuracy can be actualized. A typical wide-band radar target simulation is taken to demonstrate the preferable simulation effect of the reconstruction method of wide-band radar target echo. Finally, the radar target time-domain echo and high-resolution range profile （HRRP） are given. The results show that the HWIL simulation gives a high-resolution range distribution of wide-band radar target scattering centers.

关键词： Digital radio frequencymemory Error analysis Hardware-in-the-loop simu-lation Radar targets Scattering parameters

Effect of the addition of Mg, Ti, Ni on the decoloration performance of AlCrFeMn high entropy alloy

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Journal of Materials Science & Technology 2019年第8期35卷 1629-1635页

作者： Shikai Wu Ye pan Jie lu Ning Wang Weiji Dai Tao lu School of Materials Science and Engineering Southeast UniversityJiangsu Key Laboratory for Advanced Metallic Materials

Due to the excellent mechanical properties of high entropy alloys(HEAs), they have attracted wide attention of materials researchers, but their functional properties have rarely been reported. In order to study the functional properties of HEAs, the decoloration of azo dye Direct Blue 6(DB6) using equiatomic AlCrFeMn and AlCrFeMn M(M=Mg, Ti, Ni) HEAs synthesized by mechanical alloying was reported in this work. The decoloration rate of DB6 by ball-milled(BM) AlCrFeMn was about 3 times faster than that of by BM MgZn-based amorphous alloy, which was the best one reported in the metallic glasses so far. In order to further improve the decoloration efficiency, we considered adding the fifth elements(Mg or Ti or Ni) to AlCrFeMn. Both of Mg and Ti could improve the decoloration performance of AlCrFeMn, but Ni played a negative role. The reaction activity of AlCrFeMnMg and AlCrFeMnTi was more than 2 and 1.2 times faster than that of AlCrFeMn. The effects of initial pH, temperatures and dye concentration on the decoloration efficiency of AlCrFeMnMg during reactions were systematically investigated. The reaction activity of AlCrFeMnMg in alkaline and acidic azo dye solution was about 37.5 and 16.6 times faster than that of neutral solution, respectively. This work had implications in reaching an attractive, low cost and efficient method for functional applications of HEAs.

关键词： Alloy design Environment properties Low cost Materials synthesis Mechanical milling Mechanical properities

Impact of circumferential inlet distortion on different types of stall inceptions in a transonic compressor

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Chinese Journal of Aeronautics 2024年第11期37卷 107-117页

作者： Tianyu pan Jiandong YAN Hanan lu Qiushi LI Reserach Institute of Aero-Engine Beihang UniversityBeijing 100191China School of Energy and Power Engineering Beihang UniversityBeijing 100191China Key Laboratory of Fluid and Power Machinery Ministry of EducationXihua UniversityChengdu 610039China

The application of higher bypass ratios and lower pressure ratios significantly reduces specific fuel consumption with the development of turbofan ***,it also increases the risk of flow separation at the intake,leading to severe circumferential non-uniform inlet *** study aimed to present an experimental investigation on instability evolutions of the compressor under circumferential non-uniform inlet *** stall inceptions regarding the different spatial scales and initial locations were selected to investigate this *** experiments were carried out on one tested rig,which the stall inceptions verified with the rotational *** 65%design rotational speed(X),the stall inception was the spike,which was triggered by disturbances within serval pitches scale at the ***,the spike-type stall inception was sensitive to circumferential distortion and led to a shrunk stall margin of the *** the rotational speed increasing to 88%X,the stall inception switched to partial surge,which was induced by the flow blockage in the hub region around the *** results indicated that the partial surge was insusceptible to the circumferential distortion,which caused an extended stall margin with a lower stalled mass flow *** summary,the influence of distortion on the stability of the target compressor was found to be determined by the stall inception.

关键词： Partial surge Circumferential inlet distortion Transonic compressor Stall triggering event Loading distribution