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Insight into the development of electrolytes for aqueous zinc metal batteries from alkaline to neutral

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Chinese Chemical Letters 2024年第2期35卷 232-241页

作者： An Duan Sha luo wei Sun School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China

Aqueous zinc metal batteries are considered as promising candidates for next-generation electrochemical energy storage devices,especially for large-scale energy storage,due to the advantages of high-safety,high energy density and low *** the bridge connecting cathode and anode,electrolyte provides a realistic operating *** alkaline and neutral aqueous zinc metal batteries,issues associated with electrolyte and anode are still *** this review,we reveal the development and evolution of electrolytes for aqueous zinc metal batteries from alkaline to neutral via the description of fundamentals and challenges in terms of comparison and *** also elaborate the strategies in electrolytes regulation and highlight the basic roles and progresses in additives engineering.

关键词： Aqueous electrolytes Zinc metal batteries pH-dependent chemistry Electrolyte regulation Additives engineering

SIMULATION OF SEDIMENT-LADEN FLOW BY DEPTH-AVERAGED MODEL BASED ON UNSTRUCTURED COLLOCATED GRID

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Journal of Hydrodynamics 2007年第4期19卷 525-532页

作者： LIU shi-he luo Qiu-shi MEI Jun-ya School of Water Resource and Hydropower Wuhan University Wuhan 430072 China

The 2-D depth-averaged mathematical model for sediment-laden flows has been widely used in river control and other related engineering problems, and now it is usually solved on structured grids. Since the natural river is usually very complicated in plane boundary, and unstructured grids are more attractive in solving the problems with complicated domains, the following questions about solving 2-D depth-averaged model were discussed in this article：（1） a modified Bowyer algorithm was suggested to generate unstructured grids for natural rivers, （2） the Finite Volume Method （FVM） is employed to discretize the governing equations of the 2-D depth-averaged model and an implicit scheme was suggested with unstructured collocated grids, （3） the observed hydrological data of the Chenglingji Reach in the Yangtze River are used for verification of the presented method It seems that the suggested numerical scheme works very well, and the simulation results of both hydraulic characteristics and river bed deformation are in good agreement with the observed ones.

关键词： Bowyer algorithm unstructured grid SIMPLE algorithm

Pre-and post-zygotic reproductive isolation between co-occurring Mussaenda pubescens *** and M. shikokiana(Rubiaceae)

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Journal of Integrative Plant Biology 2014年第4期56卷 411-419页

作者： shi Chen Zhonglai luo Dianxiang Zhang Key Laboratory of Plant Resources Conservation and Sustainable Utilization South China Botanical Garden the Chinese Academy of Sciences

Reproductive isolation is a fundamental require- ment for speciation and includes several sequential stages. Few studies have determined the relative contributions of pre- and post-zygotic reproductive isolation in plants, especially between relative species with clear differentiation in flower form. To investigate the mechanisms responsible for repro- ductive isolation in sympatric A4ussaenda pubescens var. alba and Mussaenda shikokiana （Rubiaceae） in Guangxi Province, China, we made observations of flowering phenology, patterns of insect visitation, and conducted pollination experiments, including artificial hybridization. The two species had over- lapping flowering times and were pollinated by overlapping pollinators; however, their relative importance differed significantly with M. pubescens visited more commonly by bees and M. shikokiana more frequently by butterflies. Using vegetative and floral characters and molecular evidence based on nuclear ribosomal internal and external transcribed spacer regions we detected seven naturally occurring hybrids among a sample of approximately 125 individuals. Hybrids were characterized by morphologies that most closely resembled their maternal parents based on chloroplast evidence. Studies of artificially synthesized and natural hybrids demonstrated that hybrid seed had very low germination rates and naturally occurring hybrids exhibited pollen sterility. Post-zygotic reproductive isolating mechanisms play a primary role in limiting gene exchange between co-occurring species and maintaining species integrity in areas of sympatry.

关键词： Gene flow Mussaenda natural hybrids reproductiveisolation sympatric congeners

Timing of Uranium Mineralization and Geological Implications of Shazijiang Granite-Hosted Uranium Deposit in Guangxi, South China: New Constraint from Chemical U-Pb Age

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Journal of Earth Science 2015年第6期26卷 911-919页

作者： Jincheng luo Ruizhong Hu Shaohua shi State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences University of Chinese Academy of Sciences Hunan Institute of Geological Survey

Miaoershan（MES） uranium ore field is one of the most important uranium sources in China, hosts the largest Chanziping carbonaceous-siliceous-pelitic rock type uranium deposit in South China together with many other granite-hosted uranium deposits. The Shazijiang（SZJ） uranium deposit is one of the representative granite-hosted uranium deposits in the MES uranium ore field, situated in the Ziyuan, Guangxi Province, South China. Uranium mineralization in the SZJ deposit mainly occurs as uraninite with quartz and calcite veins that is spatially associated with mafic dykes in the region. The hydrothermal alteration includes silicification, carbonation and hematitization. New uraninite chemical U-Pb geochronology and petrographic evidences provide the timing constraints and new insights into the formation of the SZJ uranium deposit. The results show that the first stage of uranium mineralization formed at 97.5±4.0 Ma, whereas another stage of uranium mineralization occurred at 70.2±1.6 Ma. Two stages of uranium mineralization are fairly consistent with two episodic crustal extensions that occurred at -100 and -70 Ma throughout South China. This study indicates that there are two uranium mineralization events in SZJ uranium ore field controlled by mafic dyke, supporting that mafic dykes play an important topochemical role in uranium concentration and/or mobilization. Therefore, geochemical U-Pb age firstly reinforces that ore-forming age of the SZJ uranium deposit mainly yields at 97.5±4.0 and 70.2±1.6 Ma. Additionally, geochemical age method is particularly useful for interest samples which record information on multi-stage uranium mineralizations in South China.

关键词： Shazijiang uranium deposit uraninite U-Pb age EMPA uranium mineralization crustal extension South China.

A numerical study of the summer circulation in the southwestern Yellow Sea

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Acta Oceanologica Sinica 2016年第11期35卷 1-8页

作者： shi Fei luo Yiyong RONG Zengrui College of Oceanic and Atmospheric Sciences Ocean University of China Physical Oceanography Laboratory Ocean University of China

The Regional Ocean Modeling System（ROMS） is used to study the summer circulation in the southwestern Yellow Sea（SWYS）. The modeled currents show good agreement with observations from both drifters and moorings. While the summer current in the SWYS flows consistently northeastward on the surface with large magnitude offshore, the current below the surface layer features a cyclonic circulation roughly along the 25 m isobath. The effect of a surface wind stress and bottom thermal fronts on the circulation is investigated through a series of process-oriented numerical experiments. It is found that the southeasterly wind dominates the surface current, whereas the bottom thermal fronts, which are formed in a transition area between the vertically well-mixed region and the stratified region, are responsible for the cyclonic circulation below the surface.

关键词： southwestern Yellow Sea (SWYS) Lunan (South Shandong Province China) Trough bottom thermalfronts summer circulation

基于双目视觉和改进YOLOv8n的火灾检测及测距方法

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陕西科技大学学报 2025年第1期43卷 152-160页

作者：刘振董绍江罗家元孙世政潘学娇重庆交通大学机电与车辆工程学院重庆400074

针对火灾检测出现的漏检误检、模型参数量大及定位困难的问题,基于双目视觉和改进YOLOv8n提出了一种轻量化火灾检测及测距方法.通过双目相机拍摄图片,使用改进的检测算法YOLOv8n-AEM和现有的测距算法SGBM进行检测和测距.首先,在主干网... 详细信息

针对火灾检测出现的漏检误检、模型参数量大及定位困难的问题,基于双目视觉和改进YOLOv8n提出了一种轻量化火灾检测及测距方法.通过双目相机拍摄图片,使用改进的检测算法YOLOv8n-AEM和现有的测距算法SGBM进行检测和测距.首先,在主干网络中引入可变核卷积AKConv和EMA注意力机制,通过构建不规则卷积核有效提取火灾的特征;然后,在颈部网络中构建C2f-SCConv模块,通过特征重组降低模型参数,提高检测速度;其次,基于最小点距离改进损失函数,解决火源与光源重叠导致的漏检与误检问题;最后,增加小目标检测头,提高对小火苗的检测能力.实验结果表明,改进后的检测算法P、R、mAP分别为83.6%、76.4%、83.6%,分别提高了2.5%、3.6%、4.8%;参数量和模型大小分别为2.54 M和5.1 MB,分别降低了15.3%和15%;测距精度误差不超过2.5%,证明改进的方法能准确完成火灾的检测及测距.

关键词：火灾检测双目视觉测距 YOLOv8n 轻量化

Effects of process parameters and annealing on microstructure and properties of CoCrFeMnNi high-entropy alloy coating prepared by plasma cladding

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China Foundry 2023年第6期20卷 491-502页

作者： shi-yong wei Chao-min Wang Wen-yi Peng Ru-kai luo Yun Chen Zhen-zhen Wan Yin Jin Institute of Applied Physics Jiangxi Academy of SciencesNanchang 330090China Materials Science and Engineering School Nanchang UniversityNanchang 330029China

Plasma cladding was used to prepare a CoCrFeMnNi high-entropy alloy(HEA)coating under different *** process parameters were optimized using an orthogonal experiment design based on surface morphology quality characteristics,dilution rate,and *** optimal process parameters were determined through range and variance analysis to be a cladding current of 70 A,a cladding speed of 7 cm·min^(-1),and a powder gas flow rate of 8 L·s^(-1).During the optimized experiments,both the cladded and annealed CoCrFeMnNi HEA coatings exhibit some pores,micro-voids,and a small amount of ***,the aggregation in the annealed coating is more dispersed than that in the cladded *** cladded CoCrFeMnNi HEA coating consists of simple FCC phases,while a new Cr-rich phase precipitates from the FCC matrix after annealing the coating at a temperature range of 550℃-950℃.After annealing at 850℃,the proportion of the FCC phase decreases compared to the cladded coating,and the number of large-angle grain boundaries is significantly ***,the proportion of grains with sizes below 50μm increases from 61.7%to 74.3%.The micro-hardness and wear resistance of the cladded coating initially increases but then decreases with an increase in annealing temperature,indicating that appropriate annealing can significantly improve the mechanical properties of the CoCrFeMnNi HEA coatings by plasma *** micro-hardness of the CoCrFeMnNi HEA coatings after annealing at 650℃ increases to 274.82 HV_(0.2),while the friction coefficient decreases to below 0.595.

关键词： plasma cladding CoCrFeMnNi HEA coating process optimization annealing microstructure and mechanical property

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Chinese Journal of Electronics 2016年第4期25卷 608-613页

作者： GUO Jiansheng luo wei WANG Kun Zhengzhou Information Science and Technology Institute Unit 78179 of the PLA

By constructing three types of related-key differential characteristics,we present three corresponding related-key differential attacks on the *** the independence of the characteristics,we could recover 64 bits of the cipher’s master key with 2;chosen plain-texts,2;full-round DDP-64 encryptions and 2;bits of storage *** break the cipher,we only need to implement an exhaustive search for the rest 64 bits of the master key.

关键词： Block cipher DDP-64 block cipher Data dependent permutations(DDPs) Multiple related-key differential attacks

3D mesoporous rose-like nickel-iron selenide microspheres as advanced electrocatalysts for the oxygen evolution reaction

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Nano Research 2018年第4期11卷 2149-2158页

作者： Jiahao Yu Gongzhen Cheng wei luo College of Chemistry andMolecularSciences Wuhan University Wuhan 430072 China Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) Nankai University Tianjin 300071 China

The development of efficient and stable non-noble metal-based electrocatalysts for the oxygen evolution reaction （OER） is one of the essential challenges for the upcoming hydrogen economy. Herein, three-dimensional （3D） mesoporous nickel iron selenide with rose-like microsphere architecture was directly grown on Ni foam via a successive two-step hydrotherrnal method. The unique 3D mesoporous rose-like morphology leads to a higher number of active sites as well as fast mass and electron transport through the entire electrode, and facilitates the release of 02 bubbles formed during the OER catalysis. As a result, the synthesized Ni0.76Fe0.24Se exhibits superior OER performances, with an ultralow overpotential of 197 mV needed to produce a current density of 10 ***-2 in 1 M KOH, outperforming all transition metal selenide OER catalysts reported to date.

关键词： transition metal selenide oxygen evolution reaction NiFeSe three-dimensional (3D) rose-like microspheres