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Revealing the potential of apparent critical current density of li/garnet interface with capacity perturbation strategy

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Journal of Energy Chemistry 2023年第4期79卷 56-63页

作者： Zhihao Guo Xinhai li Zhixing Wang Huajun Guo Wenjie Peng guangchao li Guochun Yan Qihou li Jiexi Wang School of Metallurgy and Environment Central South UniversityChangsha 410083HunanChina Engineering Research Center of the Ministry of Education for Advanced Battery Materials Central South UniversityChangsha 410083HunanChina Key Laboratory of Value-added Metallurgy of Hunan Province Central South UniversityChangsha 410083HunanChina

Apparent critical current density(j_(Ac)^(a))of garnet all-solid-state lithium metal symmetric cells(ASSLSCs)is a fundamental parameter for designing all-solid-state lithium metal ***,how much the possible maximum apparent current density that a given ASSLSC system can endure and how to reveal this potential still require ***,a capacity perturbation strategy aiming to better measure the possible maximum j_(Ac)^(a)is proposed for the first *** garnet-based plane-surface structure ASSLSCs as an exemplification,the j_(Ac)^(a)is quite small when the capacity is dramatically *** a perturbed capacity of 0.001 mA h cm^(-2),the j_(Ac)^(a)is determined to be as high as 2.35 mA cm^(-2)at room *** investigation demonstrates that the capacity perturbation strategy is a feasible strategy for measuring the possible maximum j_(Ac)^(a)of li/solid electrolyte interface,and hopefully provides good references to explore the critical current density of other types of electrochemical systems.

关键词： All-solid-state lithium batteries li/solid electrolyte interface Apparent critical current density Interfacial state variation Capacity perturbation strategy

Analysis and prediction of global vegetation dynamics:past variations and future perspectives

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Journal of Forestry Research 2023年第2期34卷 317-332页

作者： guangchao li Wei Chen liqiang Mu Xuepeng Zhang Pengshuai Bi Zhe Wang Zhen Yang College of Geoscience and Surveying Engineering China University of Mining and TechnologyBeijing 100083People’s Republic of China School of Forestry Northeast Forestry UniversityHarbin 150040People’s Republic of China College of Information Science and Engineering Henan University of TechnologyZhengzhou 450001People’s Republic of China

Spatiotemporal dynamic vegetation changes affect global climate change,energy balances and the hydrological *** these dynamics over a long time series is important for the study and analysis of global environmental *** on leaf area index(LAI),climate,and radiation flux data of past and future scenarios,this study looked at historical dynamic changes in global vegetation LAI,and proposed a coupled multiple linear regression and improved gray model(CMLRIGM)to predict future global *** results show that CMLRIGM predictions are more accurate than results predicted by the multiple linear regression(MLR)model or the improved gray model(IGM)*** coupled model can effectively resolve the problem posed by the underestimation of annual average of global vegetation LAI predicted by MLR and the overestimate predicted by *** 1981 to 2018,the annual average of LAI in most areas covered by global vegetation(71.4%)showed an increase with a growth rate of 0.0028 a-1;of this area,significant increases occurred in 34.42%of the total *** 2016 to 2060,the CMLRIGM model has predicted that the annual average global vegetation LAI will increase,accounting for approximately 68.5%of the global vegetation coverage,with a growth rate of 0.004 *** growth rate will increase in the future scenario,and it may be related to the driving factors of the high emission scenario used in this *** research may provide a basis for simulating spatiotemporal dynamic changes in global vegetation conditions over a long time series.

关键词： Vegetation dynamics LAI CMLRIGM Prediction Climate Radiation

10~18 GHz高精度单片数控移相器设计

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电子设计工程 2024年第9期32卷 61-65页

作者：周宏健蒋乐李光超周睿涛中科芯集成电路有限公司江苏无锡214000

设计了一款10~18 GHz高精度单片6 bit数控移相器芯片,采用的电路结构融合了全通滤波器(APF)、高通滤波器(HPF)和低通滤波器(LPF)型移相结构。采用多个全通滤波器级联的移相结构可以在宽带内实现精准的相位偏移量,但电路结构比较复杂。... 详细信息

设计了一款10~18 GHz高精度单片6 bit数控移相器芯片,采用的电路结构融合了全通滤波器(APF)、高通滤波器(HPF)和低通滤波器(LPF)型移相结构。采用多个全通滤波器级联的移相结构可以在宽带内实现精准的相位偏移量,但电路结构比较复杂。该设计通过两种方式改进级联全通滤波器型移相结构,一是采用全通-高通网络替代全通网络,二是采用低通网络替代全通网络,可以在保持高移相精度的同时减少电路元件数量,缩小芯片尺寸。使用0.25μm GaAs PHEMT工艺制造移相器芯片,内部集成六位并行驱动器,芯片尺寸为2.7 mm×1.4 mm,测试得到10~18 GHz频段内移相精度(RMS)为2°。

关键词：宽带高精度砷化镓数控移相器全通滤波器

Graphitic nanorings for super-long lifespan lithium-ion capacitors

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Nano Research 2020年第11期13卷 2909-2916页

作者： guangchao li Zhoulan Yin Yuqing Dai Bianzheng You Huajun Guo Zhixing Wang Guochun Yan Yong liu Jiexi Wang School of Metallurgy and Environment&College of Chemistry and Chemical Engineering Central South UniversityChangsha410083China State Key Laboratory for Powder Metallurgy Central South UniversityChangsha410083China

Porous graphitic carbon nanorings(PGCNs)are proposed by smart catalytic graphitization of nano-sized graphene quantum dots(GQDs).The as-prepared PGCNs show unique ring-like morphology with diameter around 10 nm,and demonstrate extraordinary mesoporous structure,controllable graphitization degree and highly defective *** mechanism from GQDs to PGCNs is proven to be a dissolution-precipitation process,undergoing the procedure of amorphous carbon,intermediate phase,graphitic carbon nanorings and graphitic carbon ***,the relationship between particles size of GQDs precursor and graphitization degree of PGCNs products is *** unique microstructure implies PGCNs a broad prospect for energy storage *** applied as negative electrode materials in dual-carbon lithium-ion capacitors,high energy density(77.6 Wh·kg^(−1))and super long lifespan(89.5%retention after 40,000 cycles at 5.0 A·g^(−1))are *** energy density still maintains at 24.5 Wh·kg^(−1)even at the power density of 14.1 kW·kg^(−1),demonstrating excellent rate *** distinct microstructure of PGCNs together with the strategy for catalytic conversion from nanocarbon precursors to carbon nanorings opens a new window for carbon materials in electrochemical energy storage.

关键词： graphene quantum dots carbon nanorings catalytic graphitization defects lithium ion capacitors

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交互式管网缺陷检测智能识别系统研究

工程地球物理学报 2024年第2期21卷 187-195页

作者：李广超阮殿勇李涛张昊廖志颖朱培民黄河勘测规划设计研究院有限公司河南郑州450003 中国地质大学地球物理与空间信息学院湖北武汉430074

对闭路电视数据进行城市排水管道缺陷识别处理,常需要人工或者基于深度学习的方法来完成。但人工识别工作量和耗时巨大,而传统的深度学习方法还存在复杂缺陷识别准确率低和需要大量标签等问题,无法满足排水管道异常的类别检测和精确位... 详细信息

对闭路电视数据进行城市排水管道缺陷识别处理,常需要人工或者基于深度学习的方法来完成。但人工识别工作量和耗时巨大,而传统的深度学习方法还存在复杂缺陷识别准确率低和需要大量标签等问题,无法满足排水管道异常的类别检测和精确位置确定的要求。为此,发展了一种交互式的基于深度学习的排水管道缺陷内窥检测智能识别方法,可以在样本量较少的情况下不断提高识别效果。该方法通过适当的人工干预,校正识别的结果,并将识别结果自动加入到样本库中,积累和丰富各种缺陷的样本;通过对不断更新的样本的持续学习,可以迅速提高缺陷的识别准确度。在武汉市排水管道视频数据的缺陷识别试验中,虽然各类缺陷样本总共只有1627个,但总体缺陷识别准确率可以达到68%,验证了该方法的有效性,展示了该方法有良好的应用前景。

关键词：深度学习交互智能排水管道管道缺陷

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Filtration performance and modeling of granular bed for dust removal from coal pyrolytic vapors

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Chinese Journal of Chemical Engineering 2024年第1期65卷 35-42页

作者： Shuaiqiang Yang lin Du guangchao Ding Runguo liu Wenli Song Songgeng li State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Petrochemical Engineering Yan’an Vocational and Technical CollegeYan’an 716000China Sino-Danish College University of Chinese Academy of SciencesBeijing 100049China

Dust removal from pyrolytic vapors at high temperatures is an obstacle to the industrialization of the coal pyrolysis *** this work,a granular bed with expanded perlites as filtration media was designed and integrated into a 10 t·d^(–1)coal pyrolysis *** testing results showed that around 97.56%dust collection efficiency was *** a result,dust content in tar was significantly *** pressure drop of the granular bed maintained in the range of 356 Pa to 489 *** dust size in the effluent after filtration exhibited a bimodal distribution,which was attributed to the heterogeneity of the dust *** effects of filtration bed on pyrolytic product yields were also discussed.A modified filtration model based on the macroscopic phenomenological theory was proposed to describe the performance of the granular *** computation results were well agreed with the experimental data.

关键词： Granular bed filtration Dust removal Pyrolysis Filtration Fixed-bed

Functional groups to modify g-C3N4 for improved photocatalytic activity of hydrogen evolution from water splitting

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Chinese Chemical Letters 2020年第6期31卷 1648-1653页

作者： Fan Yu Laichun Wang Qiuju Xing Dengke Wang Xunheng Jiang guangchao li Anmin Zheng Fanrong Ai Jian-Ping Zou Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle Nanchang Hangkong UniversityNanchang 330063China State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics National Center for Magnetic Resonance in WuhanWuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071China School of Mechanical&Electronic Engineering Nanchang UniversityNanchang 330031 China

Rational modification by functional groups was regarded as one of efficient methods to improve the photocatalytic performance of graphitic carbon nitride(g-C3 N4).Herein,g-C3 N4 with yellow(Y-GCN)and brown(C-GCN)were prepared by using the fresh urea and the urea kept for five years,respectively,for the first *** results show that the H2 production rate of the C-GCN is 39.06μmol/h,which is about 5 times of the ***,in terms of apparent quantum efficiency(AQ.E)at 420 nm,C-GCN has a value of 6.3%and nearly 7.3 times higher than that of Y-GCN(0.86%).The results of XRD,IR,DRS,and NMR show,different from Y-GCN,a new kind of functional group of—N=CH—was firstly in-situ introduced into the C-GCN,resulting in good visible light absorption,and then markedly improving the photocatalytic *** calculation also confirms the effect of the—N=CH—group band structure of ***,XPS results demonstrate that the existence of—N=CH—groups in C-GCN results in tight interaction between C-GCN and Pt nanoparticles,and then improves the charge separation and photocatalytic *** present work demonstrates a good example of"defect engineering"to modify the intrinsic molecular structure of g-C3N4 and provides a new avenue to enhance the photocatalytic activity of g-C3N4 via facile and environmental-friendly method.

关键词： Functional groups Graphitic carbon nitride Hydrogen evolution Photocatalysis Synthesis

跨音速风扇转子冰撞击损伤规律及抗冰撞击改进设计研究

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装备环境工程 2024年第8期21卷 96-110页

作者：邢怀程徐强仁王立志李广超赵巍赵庆军沈阳航空航天大学航空发动机学院沈阳110136 中国科学院工程热物理研究所北京100190 中国科学院工程热物理研究所轻型涡轮动力全国重点实验室北京100190 中国科学院大学航空宇航学院北京100190 中国科学院分布式冷热电联供系统北京市重点实验室北京100190

目的揭示脱落冰形状、运动轨迹和姿态对航空发动机风扇转子叶片的撞击损伤规律,增强叶片的抗冰撞击能力。方法采用LS-DYNA进行数值模拟,开展脱落冰与叶片的撞击过程和叶型改进设计研究。结果叶片的撞击损伤程度受脱落冰结构强度的影响,... 详细信息

目的揭示脱落冰形状、运动轨迹和姿态对航空发动机风扇转子叶片的撞击损伤规律,增强叶片的抗冰撞击能力。方法采用LS-DYNA进行数值模拟,开展脱落冰与叶片的撞击过程和叶型改进设计研究。结果叶片的撞击损伤程度受脱落冰结构强度的影响,在同样的撞击条件下,叶片受球体冰撞击损伤最严重,而受片体冰撞击损伤最轻。叶片的损伤程度由叶片和脱落冰之间的相对速度和叶片切割冰块的质量共同决定,叶片切割脱落冰的质量越大,塑性变形越严重。当脱落冰入射角为45°时,叶片损伤最严重,对叶片的最大撞击力为17828 N,最大内能达到126 J;当冰片从原始姿态绕y轴旋转90°时,对叶片前缘的撞击载荷最大,叶片塑性变形最严重。改进后,叶片受沿45°入射角脱落冰撞击后最大内能减小16%,失速裕度提高16.2%,峰值效率提高0.33%。结论跨音速风扇转子撞击损伤位置在前缘附近,增大叶片进口几何角和局部厚度能显著提高叶片抗冰撞击能力。

关键词：航空发动机跨音速风扇叶片脱落冰损伤规律改进设计

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Recent advances of mechanosensitive genes in vascular endothelial cells for the formation and treatment of atherosclerosis

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Genes & Diseases 2024年第3期11卷 206-219页

作者： Shuyu li Zichen Xu Yi Wang lizhao Chen Xiangxiu Wang Yanghao Zhou Daoxi Lei guangchao Zang Guixue Wang Key Laboratory of Biorheological Science and Technology of Ministry of Education National and Local Joint Engineering Laboratory for Vascular ImplantsBioengineering College of Chongqing UniversityChongqing 400030China College of Basic Medical Sciences Chongqing Medical UniversityChongqing 400016China Department of Neurosurgery Daping HospitalArmy Medical Center of PLAArmy Medical UniversityChongqing 400042China

Atherosclerotic cardiovascular disease and its complications are a high-incidence disease *** studies have shown that blood flow shear has a huge impact on the function of vascular endothelial cells,and it plays an important role in gene regulation of pro-inflammatory,pro-thrombotic,pro-oxidative stress,and cell *** impor-tant endothelial cell mechanosensitive genes have been discovered,including KLK10,CCN gene family,NRP2,YAP,TAZ,HIF-1α,NF-kB,FOS,JUN,TFEB,KLF2/KLF4,NRF2,and *** of them have been intensively studied,whereas the relevant regulatory mechanism of other genes remains *** on these mechanosensitive genes will provide new strategies for therapeutic intervention in atherosclerotic vascular ***,this article reviews the mechanosensitive genes affecting vascular endothelial cells,including classical pathways and some newly screened genes,and summarizes the latest research progress on their roles in the pathogenesis of atherosclerosis to reveal effective therapeutic targets of drugs and provide new insights foranti-atherosclerosis.

关键词： Atherosclerosis Blood flow Endothelial cell Mechanosensitive gene Therapeutic target