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The Short-Duration Heavy Rainfall in Different Quadrants of Northeast China Cold Vortices

Journal of Meteorological Research 2024年第2期38卷 321-338页

作者： Lei YANG yongguang ZHENG Liaoning Meteorological Disaster Monitoring and Early Warning Center Shenyang 110166 National Meteorological Centre China Meteorological AdministrationBeijing 100081 China Meteorological Administration Tornado Key Laboratory Foshan 528315

The Northeast China cold vortex(NCCV)is one of the main synoptic-scale systems causing short-duration heavy rainfall(SDHR)in Northeast China.Environmental conditions(e.g.,water vapor,instability,and vertical wind shear)are known to be distinctly different over the four quadrants of NCCVs,rendering prediction of the SDHR related to NCCVs(NCCV_SDHR)more challenging.Based on 5-yr hourly rainfall observations from 3196 automatic weather stations and ERA5 reanalysis data,10,232 NCCV_SDHR events were identified and divided into four quadrant groups according to their relative position to the center of the NCCV(CVC).The results show that the southeast quadrant features the highest frequency of SDHR,with stronger intensity,longer duration,and wider coverage;and the SDHR in different quadrants presents different formation mechanisms and varied temporal evolution.A new coordinate system is established relative to the CVC that uses the CVC as the origin and the radius of the NCCV(r CV)as the unit distance.In this new coordinate system,all of the NCCV_SDHR events in the 5-yr study period are synthesized.It is found that the occurrence frequency of NCCV_SDHR initially increases and then decreases with increasing distance from the CVC.The highest frequency occurs mainly between 0.8 and 2.5 times r CV from the CVC in the southeast quadrant.This can be attributed to the favorable conditions,such as convergence of the low-level shear line and abundant water vapor,which are concentrated in this region.Furthermore,high-frequency NCCV_SDHR larger than 50 mm(NCCV_SDHR50)is observed to be closer to the CVC.When NCCV_SDHR50occurs,the NCCV is in closer proximity to the subtropical high,resulting in stronger low-level convergence and more abundant water vapor.Additionally,there are lower lifting condensation levels and stronger 0-6-and 0-1-km vertical wind shears in these environments.These findings provide a valuable reference for more accurate prediction of NCCV_SDHR.

关键词： Northeast China cold vortex short-duration heavy rainfall statistical characteristics environmental conditions

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Solid Component Fraction in Multi-Phase Flows Using Electrical Resistance Tomography and Kalman Filter

Solid Component Fraction in Multi-Phase Flows Using Electric...

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第三十九届中国控制会议

作者： Liu Yang Shihong Yue yongguang tan School of Electrical and Information Engineering Tianjin University

One of the major tasks in multi-phase flow detection is solid component fraction calculation.According to the Electrical Resistance Tomography(ERT) measurement,the mainstream method is to use Maxwell-Garnett formula to derive solid component fraction of multi-phase flow from conductivity.In dredging engineering fields,measurement data of multiphase flows in horizontal and vertical ducts is typically obtained by two sensor planes.However,the estimated solid component fraction remains rather inaccurate due to linear back projection(LBP) algorithm limitation,and noisy data on the available ERT measurements in most cases.In this paper,we proposed a new solid component fraction estimation method according to Kalman filter and ERT.This new method uses the complementarity of dual sensor data to improve measurement accuracy.Facing the real needs in dredging engineering fields,solid component fraction of the typical flow were tested.The results validate our proposed methods in a series of typical flow conditions.

关键词： Electrical Resistance Tomography component fraction Kalman filter Multiphase flow

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Direct amplification of femtosecond optical vortices in a single-crystal fiber

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Photonics Research 2024年第1期12卷 27-32页

作者： CHANGSHENG ZHENG TIANYI DU LEI ZHU ZHANXIN WANG KANGZHEN TIAN yongguang ZHAO ZHIYONG YANG HAOHAI YU VALENTIN PETROV Jiangsu Key Laboratory of Advanced Laser Materials and Devices School of Physics and Electronic EngineeringJiangsu Normal UniversityXuzhou 221116China State Key Laboratory of Crystal Materials and Institute of Crystal Materials Shandong UniversityJinan 250100China Max Born Institute for Nonlinear Optics and Short Pulse Spectroscopy 12489 BerlinGermany

Spatially twisted light with femtosecond temporal structure is of particular interest in strong-field physics and light–matter interactions.However,present femtosecond vortex sources exhibit limited power handling capabilities,and their amplification remains an ongoing challenge particularly for high-order orbital angular momentum(OAM)states due to several inherent technical difficulties.Here,we exploit a straightforward approach to directly amplify a femtosecond optical vortex(FOV,OAM=-8?)by using a two-stage single-crystal fiber(SCF)amplifier system without pulse stretching and compression in the time domain,delivering 23-W,163-fs pulses at a repetition rate of1 MHz.The spatial and temporal features are well-conserved during the amplification,as well as the high modal purity(>96%).The results indicate that the multi-stage SCF amplifier system is particularly suited for direct amplification of high-order FOVs.The generated high-power femtosecond OAM laser beams are expected to help reveal complex physical phenomena in light–matter interactions and pave the way for practical applications in attoscience,laser plasma acceleration,and high-dimension micromachining.

关键词： fiber amplifier crystal

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Back-contact configuration energizes perovskite photovoltaic modules

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Nano Research Energy 2024年第2期3卷 7-11页

作者： Xiaoyu Yang yongguang Tu Fengjun Ye Zheng Bao State Key Laboratory for Artificial Microstructure and Mesoscopic Physics School of PhysicsPeking UniversityBeijing 100871China Frontiers Science Center for Flexible Electronics(FSCFE) Xi’an Institute of Flexible Electronics(IFE)&Xi’an Institute of Biomedical Materials and Engineering(IBME)Northwestern Polytechnical University Xi’anShaanxi 710072China Beijing Solarverse Optoelectronic Technology Co. Ltd.Beijing 100176China

In this viewpoint,recent hot topics in the photovoltaic community,interdigitated back contact(IBC)cells,are systematically reviewed from the view of device configuration.Two categories of IBC designs on the most popular perovskite solar cells(PSCs)were discussed,and a planar back-contact perovskite module was first proposed.The device configuration,fabrication methods,working mechanism,optimization strategies,and future development directions of this novel PSC module were put forward to show its superiorities in the module performance,processing difficulty,and extensible functionality among present perovskite modules,presenting promising potential to improve the competitiveness of perovskite technology in the photovoltaic market.

关键词： perovskite solar cell back-contact photovoltaic technology device configuration

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Stabilizing zinc anode using zeolite imidazole framework functionalized separator for durable aqueous zinc-ion batteries

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Journal of Energy Chemistry 2024年第3期90卷 23-31,I0003页

作者： Weisong Zhang Xinyan Zhu Ling Kang Ziyu Peng Jing Zhu Liang Pan Lei Dai Shude Liu Ling Wang yongguang Liu Zhangxing He School of Chemical Engineering North China University of Science and TechnologyTangshan 063009HebeiChina Shanghai Key Laboratory of Multidimensional Information Processing East China Normal UniversityShanghai 201620China College of Textiles Donghua UniversityShanghai 201620China

Aqueous zinc-ion batteries(AZIBs) hold great promise as a viable alternative to lithium-ion batteries owing to their high energy density and environmental friendliness.However,AZIBs are consistently plagued by the formation of zinc dendrites and concurrent side reactions,which significantly diminish their overall service life,In this study,the glass fiber separator(GF) is modified using zeolite imidazole salt framework-8(ZIF-8),enabling the development of efficient AZIBs.ZIF-8,which is abundant in nitrogen content,efficiently regulates the desolvation of [Zn(H_(2)O)_(6)]^(2+) to inhibit hydrogen production.Moreover,it possesses abundant nanochannels that facilitate the uniform deposition of Zn~(2+) via a localized action,thereby hindering the formation of dendrites.The insulating properties of ZIF-8 help prevent Zn^(2+) and water from trapping electron reduction at the layer surface,which reduces corrosion of the zinc anode.Consequently,ZIF-8-GF achieves the even transport of Zn^(2+) and regulates the homogeneous deposition along the Zn(002) crystal surface,thus significantly enhancing the electrochemical performance of the AZIBs,In particular,the Zn|Zn symmetric cell with the ZIF-8-GF separator delivers a stable cycle life at0.5 mA cm^(-2) of 2300 h.The Zn|ZIF-8-GF|MnO_(2) cell exhibits reduced voltage polarization while maintaining a capacity retention rate(93.4%) after 1200 cycles at 1.2 A g^(-1) The unique design of the modified diaphragm provides a new approach to realizing high-performance AZIBs.

关键词： Aqueous zinc-ion batteries Separators modifications ZIF-8 Zn deposition Dendrite-free

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Design Principles and Mechanistic Understandings of Non-Noble-Metal Bifunctional Electrocatalysts for Zinc-Air Batteries

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Nano-Micro Letters 2024年第9期16卷 13-48页

作者： Yunnan Gao Ling Liu Yi Jiang Dexin Yu Xiaomei Zheng Jiayi Wang Jingwei Liu Dan Luo yongguang Zhang Zhenjia Shi Xin Wang Ya‑Ping Deng Zhongwei Chen Power Battery and Systems Research Center State Key Laboratory of CatalysisDalian Institute of Chemical PhysicsDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023People’s Republic of China Department of Chemical Engineering University of WaterlooWaterlooON N2L 3G1Canada Institute of Carbon Neutrality Zhejiang Wanli UniversityNingbo 315100People’s Republic of China College of Materials and Chemistry China Jiliang UniversityHangzhou 310018People’s Republic of China

Zinc-air batteries(ZABs)are promising energy storage systems because of high theoretical energy density,safety,low cost,and abundance of zinc.However,the slow multi-step reaction of oxygen and heavy reliance on noble-metal catalysts hinder the practical applications of ZABs.Therefore,feasible and advanced non-noble-metal elec-trocatalysts for air cathodes need to be identified to promote the oxygen catalytic reaction.In this review,we initially introduced the advancement of ZABs in the past two decades and provided an overview of key developments in this field.Then,we discussed the work-ing mechanism and the design of bifunctional electrocatalysts from the perspective of morphology design,crystal structure tuning,interface strategy,and atomic engineering.We also included theoretical studies,machine learning,and advanced characterization technologies to provide a comprehensive understanding of the structure-performance relationship of electrocatalysts and the reaction pathways of the oxygen redox reactions.Finally,we discussed the challenges and prospects related to designing advanced non-noble-metal bifunctional electrocatalysts for ZABs.

关键词： Zinc-air batteries Bifunctional electrocatalysts Design principles Mechanistic understandings

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Size selectivity of combined square and diamond mesh codends of shrimp beam trawl for banded scad Caranx(Atule)kalla in the northern South China Sea

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Journal of Oceanology and Limnology 2018年第5期36卷 1880-1890页

作者：杨炳忠杨吝谭永光晏磊张鹏李杰 South China Sea Fisheries Research Institute Chinese Academy of Fishery SciencesKey Lab of South China Sea Fishery Resources Exploitation&UtilizationMinistry of AgricultureGuangzhou 510300China

The shrimp beam trawl fishery in the northern South China Sea is characterized by high by-catch and poor selectivity problems.Among by-catch species,banded scad(Caranx(Atule)kalla)is economically the most important one.The aim of this study is to improve the selective properties of codends for banded scad.Size selectivity of 2 traditional diamond mesh codends,with mesh size 25 and 30 mm(defined as D25 and D30,respectively),and 4 new combined square and diamond mesh codends,with25 mm square-mesh and 25 mm diamond-mesh(S25+D25),30 mm square-mesh and 25 mm diamondmesh(S30+D25),35 mm square-mesh and 25 mm diamond-mesh(S35+D25),and 35 mm square-mesh and18 mm diamond-mesh(S35+D18),were tested for banded scad in shrimp beam trawl fishery of the South China Sea.A total of 54 valid hauls were finished using the covered codend method,and 5750 banded scad were caught.Selective parameters were obtained using the logistic equation with the maximum likelihood method,by incorporating the between-haul variation.The results show that the present minimum mesh size for shrimp beam trawl in the South China Sea,25-mm diamond mesh size,is insufficient to release immature banded scad.The S35+D25 codend is proved to be the most eff ective codend to release immature banded scad,and its 50%retention length(L _(50))is larger than the minimum landing size(MLS=63.5 mm)of banded scad.However,the 95%confidence intervals of L _(50) overlap among the three combined mesh codends,the S25+D25,S30+D25 and S35+D25 codend.For a sustainable exploitation of banded scad,larger mesh sizes are suggested to be investigated for the combined mesh codends.

关键词：虾束拖网渔业渔场养殖业养殖技术

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自动驾驶电力机车牵引变流器中IGBT寿命损耗优化策略

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中国电机工程学报 2021年第18期41卷 6381-6389页

作者：徐绍龙倪强李学明谭永光中南大学交通运输工程学院湖南省长沙市410083 广东工业大学自动化学院广东省广州市510006 株洲中车时代电气股份有限公司湖南省株洲市412001

作为牵引变流器的核心部件,IGBT模块寿命损耗很大程度上直接决定了牵引变流器全寿命周期成本。为此文中在不影响机车整车输出牵引性能的基础上,提出一种基于电力机车各轴牵引力动态分配的IGBT寿命损耗最优策略,以降低牵引变流器全寿命... 详细信息

作为牵引变流器的核心部件,IGBT模块寿命损耗很大程度上直接决定了牵引变流器全寿命周期成本。为此文中在不影响机车整车输出牵引性能的基础上,提出一种基于电力机车各轴牵引力动态分配的IGBT寿命损耗最优策略,以降低牵引变流器全寿命周期成本。基于牵引电机结构原理与相关现场数据,该方法首先建立IGBT寿命损耗与牵引力及区间速度的量化模型;然后基于上述量化模型与机车自动驾驶系统规划的区间速度及牵引力发挥曲线对不同牵引力分配策略下逆变器IGBT寿命损耗进行实时计算,得出寿命损耗最优的牵引电机功率分配方案,控制机车各轴牵引电机输出。最后,基于HXD1自动驾驶机车现场某区间运行数据,对所提方法进行测试,验证所提方法的有效性。

关键词： IGBT寿命损耗模型结温计算牵引力分配

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典型地层下TBM滚刀刀座系统振动特性实验研究

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工程设计学报 2024年第2期31卷 263-270页

作者：郑永光杨妹中铁工程装备集团有限公司河南郑州450016 中南大学机电工程学院湖南长沙410083

在全断面硬岩隧道掘进机(tunnel boring machine,TBM)滚刀破岩过程中,强冲击载荷下产生的切削应力通过刀座系统传递至刀盘,引起刀座系统剧烈振动,造成螺栓松动断裂甚至滚刀掉落等严重的工程问题。为此,通过开展破岩实验来研究TBM滚刀刀... 详细信息

在全断面硬岩隧道掘进机(tunnel boring machine,TBM)滚刀破岩过程中,强冲击载荷下产生的切削应力通过刀座系统传递至刀盘,引起刀座系统剧烈振动,造成螺栓松动断裂甚至滚刀掉落等严重的工程问题。为此,通过开展破岩实验来研究TBM滚刀刀座系统的振动特性。利用多功能刀具切削性能测试实验台开展TBM滚刀切削红砂岩和花岗岩的实验,并采集滚刀破岩过程中的三向载荷和刀轴振动加速度数据。通过对比分析红砂岩和花岗岩地层下滚刀破岩的载荷—时间历程曲线,得到破岩过程中滚刀刀座系统载荷的动态变化特性,以及不同地层下滚刀刀轴的振动响应特性。研究结果可为TBM滚刀刀座系统的减振设计提供理论依据。

关键词：全断面硬岩隧道掘进机滚刀破岩滚刀刀座系统载荷特性振动响应

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中药通过细胞外信号调节激酶信号通路调控胃癌的研究进展

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世界中医药 2024年第7期19卷 1043-1048,1055页

作者：赵颖异吕星谭雅兰韩永光河南中医药大学药学院郑州450046

胃癌在我国发病率和死亡率较高,存在发现晚、5年生存率低的特点,手术切除仍然是临床治疗的主要方法。大鼠肉瘤蛋白(Ras)/迅速加速性纤维肉瘤蛋白(Raf)/丝裂原活化的细胞外信号调节激酶(MEK)/细胞外信号调节激酶(ERK)信号通路在调控细胞... 详细信息

胃癌在我国发病率和死亡率较高,存在发现晚、5年生存率低的特点,手术切除仍然是临床治疗的主要方法。大鼠肉瘤蛋白(Ras)/迅速加速性纤维肉瘤蛋白(Raf)/丝裂原活化的细胞外信号调节激酶(MEK)/细胞外信号调节激酶(ERK)信号通路在调控细胞增殖、转移、凋亡等方面具有非常重要的作用,与胃癌的发生与发展密切相关。近年来,很多学者探索调控Ras/Raf/MEK/ERK信号通路治疗胃癌的作用机制,在信号转导机制研究、靶向抑制剂筛选、中医药治疗等方面取得大量成果,实验验证在胃癌的治疗中干预其信号传递具有良好的效果和应用前景。

关键词：大鼠肉瘤蛋白/迅速加速性纤维肉瘤蛋白/丝裂原活化的细胞外信号调节激酶/细胞外信号调节激酶(Ras/Raf/MEK/ERK)信号通路胃癌基因突变抑制剂靶向治疗中药研究进展作用机制

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