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Raindrop Size Distributions in the Zhengzhou Extreme Rainfall Event on 20 July 2021:Temporal-Spatial Variability and Implications for Radar QPE

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Journal of Meteorological Research 2024年第3期38卷 489-503页

作者： Liman CUI Haoran LI Aifang SU Yang ZHANG xiaona LYU le xi Yuanmeng ZHANG Henan Key Laboratory of Agrometeorological Support and Applied Technique China Meteorological AdministrationZhengzhou450003China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing100081China Henan Meteorological Observatory Zhengzhou450003China

In this study,a regional Parsivel OTT disdrometer network covering urban Zhengzhou and adjacent areas is employed to investigate the temporal-spatial variability of raindrop size distributions(DSDs)in the Zhengzhou extreme rainfall event on 20 July *** rain rates observed by disdrometers and rain gauges from six operational sites are in good agreement,despite significant site-to-site variations of 24-h accumulated rainfall ranging from 198.3 to 624.1 *** Parsivel OTT observations show prominent temporal-spatial variations of DSDs,and the most drastic change was registered at Zhengzhou Station where the record-breaking hourly rainfall of 201.9 mm over 1500-1600 LST(local standard time)was *** hourly rainfall is characterized by fairly high concentrations of large raindrops,and the mass-weighted raindrop diameter generally increases with the rain rate before reaching the equilibrium state of DSDs with the rain rate of about 50 mm h^(−1).Besides,polarimetric radar observations show the highest differential phase shift(K_(dp))and differential reflectivity(Z_(dr))near surface over Zhengzhou Station from 1500 to 1600 *** light of the remarkable temporal-spatial variability of DSDs,a reflectivity-grouped fitting approach is proposed to optimize the reflectivity-rain rate(Z-R)parameterization for radar quantitative precipitation estimation(QPE),and the rain gauge measurements are used for *** results show an increase of mean bias ratio from 0.57 to 0.79 and a decrease of root-mean-square error from 23.69 to 18.36 for the rainfall intensity above 20.0 mm h^(−1),as compared with the fixed Z-R *** study reveals the drastic temporal-spatial variations of rain microphysics during the Zhengzhou extreme rainfall event and warrants the promise of using reflectivity-grouped fitting Z-R relationships for radar QPE of such events.

关键词： extreme rainfall raindrop size distribution radar quantitative precipitation estimation(QPE)

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Effect of applied electric fields on supralinear dendritic integration of interneuron

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Chinese Physics B 2024年第2期33卷 84-95页

作者：樊亚琴魏熙乐卢梅丽伊国胜 Tianjin Key Laboratory of Process Measurement and Control School of Electrical and Information EngineeringTianjin UniversityTianjin 300072China School of Information Technology Engineering Tianjin University of Technology and EducationTianjin 300222China

Evidences show that electric fields(EFs)induced by the magnetic stimulation could modulates brain activities by regulating the excitability of GABAergic ***,it is still unclear how and why the EF-induced polarization affects the interneuron response as the interneuron receives NMDA synaptic *** the key role of NMDA receptor-mediated supralinear dendritic integration in neuronal computations,we suppose that the applied EFs could functionally modulate interneurons’response via regulating dendritic *** first,we build a simplified multi-dendritic circuit model with inhomogeneous extracellular potentials,which characterizes the relationship among EF-induced spatial polarizations,dendritic integration,and somatic *** performing model-based singular perturbation analysis,it is found that the equilibrium point of fast subsystem can be used to asymptotically depict the subthreshold input–output(sI/O)relationship of dendritic *** predicted that EF-induced strong depolarizations on the distal dendrites reduce the dendritic saturation output by reducing driving force of synaptic input,and it shifts the steep change of sI/O curve left by reducing stimulation threshold of triggering NMDA ***,the EF modulation prefers the global dendritic integration with asymmetric scatter distribution of NMDA ***,we identify the respective contribution of EF-regulated dendritic integration and EF-induced somatic polarization to an action potential generation and find that they have an antagonistic effect on AP generation due to the varied NMDA spike threshold under EF stimulation.

关键词： GABAergic interneuron electrical field supralinear dendritic integration action potential generation

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糖动态修饰与生物识别的原位化学探测

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中国科学：化学 2024年第5期54卷 716-725页

作者：胡习乐贺晓鹏华东理工大学化学与分子工程学院费林加诺贝尔奖科学家联合研究中心结构可控先进功能材料及其制备教育部重点实验室上海200237 中国人民解放军海军军医大学国家肝癌科学中心 “肝癌分子网络调控与靶向干预”教育部重点实验室上海市肝胆肿瘤生物学重点实验室上海200438

随着人类基因组学与蛋白质组学的蓬勃发展,人类糖组学解码成为了21世纪至关重要的科学命题.然而适用于糖组学研究,尤其是能在活细胞原位精细探测糖生物学信息动态变化的高效、通用化学工具仍相对稀缺.作者团队长期致力于糖动态修饰(生... 详细信息

随着人类基因组学与蛋白质组学的蓬勃发展,人类糖组学解码成为了21世纪至关重要的科学命题.然而适用于糖组学研究,尤其是能在活细胞原位精细探测糖生物学信息动态变化的高效、通用化学工具仍相对稀缺.作者团队长期致力于糖动态修饰(生物分子糖基化与去糖基化)和糖介导生物识别(糖与凝集素或其它生物分子选择性相互作用)的原位示踪,发展了多种荧光分子探针原型,实现了上述糖生物学过程的动态探测与免标记高通量筛选.本文将系统介绍上述可用于糖生物学研究的全新化学技术原理,及其在凝集素、病毒、细菌以及哺乳动物细胞等不同结构尺度研究模型上的实用范例,最终提出该类技术方法的后续发展方向.

关键词：化学生物学糖组学荧光探针动态原位活细胞

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基于神经网络的HEVC帧间预测方法及其硬件研究

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中国集成电路 2024年第4期33卷 75-81页

作者：陶乐溪施隆照福州大学物理与信息工程学院

相比于H.264,高效视频编码标准(HEVC)提出了许多新技术,提高了编码性能,但是也显著提高了编码复杂度。本文从硬件实现的角度出发,对已有的帧间CU划分预测神经网络的结构进行了多方面的优化,使其参数减少了70%,加法和乘法运算分别减少了... 详细信息

相比于H.264,高效视频编码标准(HEVC)提出了许多新技术,提高了编码性能,但是也显著提高了编码复杂度。本文从硬件实现的角度出发,对已有的帧间CU划分预测神经网络的结构进行了多方面的优化,使其参数减少了70%,加法和乘法运算分别减少了60%、58.2%。并对优化后的卷积神经网络参数采用10位定点数方案进行定点化处理,进一步有效减少硬件资源的开支。对比于HEVC参考软件(HM16.5),优化后网络引起的BD-BR和BD-PSNR平均损失为1.718%和-0.056dB,平均节省35%~52%的编码复杂度,并且定点化处理后引起的性能损失可忽略不计。

关键词： HEVC 帧间预测卷积神经网络低复杂度神经网络定点化

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lessons from transulnar access for repeat percutaneous coronary intervention after radial artery occlusion

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Chinese Medical Journal 2020年第12期133卷 1497-1498页

作者： xi-le Bi Qing-Sheng Wang Department of Cardiology The First Hospital of QinhuangdaoQinhuangdaoHebei 066000China

To the Editor:An 80-year-old man presented to the Cardiology Department with substernal pain of 20 minutes duration on August 13,*** reviewed the patient’s case history record,which included two transradial access interventions using 6F sheaths(11-cmlong,Cordis Corporation,FL,USA).On February 13,2009,the patient had presented with an acute inferior wall myocardial infarction and underwent percutaneous coronary intervention(PCI)via the right radial *** February 19,2009,the patient underwent a second intervention,also via right radial artery access,for an elective anterior descending branch *** patient ceased smoking after the first *** this admission,before the third intervention,the patient had a weak radial pulse,but his right hand was asymptomatic.

关键词： coronary acute radial

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Phase Evolution of Cubic ZnS Annealed in Mild Oxidizing Atmosphere

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Chinese Physics letters 2012年第3期29卷 227-230页

作者： XUE Shu-Wen ZHANG Jun SHAO le-xi Department of Physics Zhanjiang Normal CollegeZhanjiang 524048

ZnS thin films are prepared by thermal evaporation of high-purity ZnS powder on quartz glass *** samples were annealed in floating argon at temperatures from 300℃to 900℃.The effects of annealing temperature on the structural and optical properties were investigated by x-ray diffraction(XRD),scanning electron microscope(SEM)and optical *** results show that annealing below 500℃is beneficial to improve the quality of ZnS *** the annealing temperature exceeds 500℃,ZnS is gradually oxidized into ZnSO4,which has evident influences on the structural and optical properties of ZnS films.

关键词： annealing purity floating

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Rich defects and nanograins boosted formaldehyde sensing performance of mesoporous polycrystalline ZnO nanosheets

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Rare Metals 2022年第7期41卷 2292-2304页

作者： le-xi Zhang Ming-Mei Zhao Yan-Yan Yin Yue xing Li-Jian Bie School of Materials Science and Engineering Tianjin Key Laboratory for Photoelectric Materials and DevicesKey Laboratory of Display Materials and Photoelectric Devices(Ministry of Education)National Demonstration Center for Experimental Function Materials EducationTianjin University of TechnologyTianjin 300384China Department of Environmental Science and Engineering Nankai University Binhai CollegeTianjin 300270China

Comprehensive consideration of structural and electronic sensitization is of significant importance for rational design and assembly of high-performance gas sensors based on metal *** this work,hierarchically mesoporous ZnO nanosheets are synthesized via a hydrothermal method followed by *** characterization reveals polycrystalline feature of these ZnO nanosheets rich in mesopores and *** sensing performance of as-synthesized ZnO nanosheets was sys-tematically investigated,taking formaldehyde as probe *** with commercial ZnO nanoparticles,ZnO nanosheets exhibited enhanced formaldehyde sensing properties,including lower operation temperature,higher sensitivity,faster response,and smaller detection ***,the response(S=227.4)of ZnO nanosheets to 200×10^(-6) formaldehyde is about 17 times larger than that of ZnO nanoparticles(S=13.5).Excluding effects of grain size and surface area,enhanced sensing properties,especially response value,are credited in large part to synergistic actions of surface defects,grain boundaries,as well as unique structural advantage of ZnO ***,this work offers a guideline for boosting performance of metal oxide-based gas sensors via surface defect control and grain boundary construction.

关键词： performance polycrystalline grain

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Characteristics analysis of acupuncture electroencephalograph based on mutual information lempel-Ziv complexity

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Chinese Physics B 2012年第2期21卷 561-568页

作者： Luo xi-Liu Wang Jiang Han Chun-xiao Deng Bin Wei xi-le Bian Hong-Rui School of Electrical and Automation Engineering Tianjin UniversityTianjin 300072China School of Automation and Electrical Engineering Tianjin University of Technology and EducationTianjin 300222China

As a convenient approach to the characterization of cerebral cortex electrical information, electroencephalograph （EEG） has potential clinical application in monitoring the acupuncture effects. In this paper, a method composed of the mutual information method and lempel-Ziv complexity method （MILZC） is proposed to investigate the effects of acupuncture on the complexity of information exchanges between different brain regions based on EEGs. In the experiments, eight subjects are manually acupunctured at ＇Zusanli＇ acupuncture point （ST-36） with different frequencies （i.e., 50, 100, 150, and 200 times/min） and the EEGs are recorded simultaneously. First, MILZC values are compared in general. Then average brain connections are used to quantify the effectiveness of acupuncture under the above four frequencies. Finally, significance index P values are used to study the spatiality of the acupuncture effect on the brain. Three main findings are obtained：（i） MILZC values increase during the acupuncture; （ii） manual acupunctures （MAs） with 100 times/rain and 150 times/min are more effective than with 50 times/min and 200 times/rain; （iii） contralateral hemisphere activation is more prominent than ipsilateral hemisphere＇s. All these findings suggest that acupuncture contributes to the increase of brain information exchange complexity and the MILZC method can successfully describe these changes.

关键词： electroencephalograph acupuncture mutual information lempel Ziv complexitymethod

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Ultrathin CeO_(2) nanosheets as bifunctional sensing materials for humidity and formaldehyde detection

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Rare Metals 2021年第6期40卷 1614-1621页

作者： Peng Zhang le-xi Zhang Heng Xu Yue xing Jing-Jing Chen Li-Jian Bie School of Materials Science and Engineering Tianjin University of TechnologyTianjin 300384China Tianjin Key Laboratory for Photoelectric Materials and Devices Tianjin 300384China Key Laboratory of Display Materials and Photoelectric Devices(Ministry of Education) Tianjin 300384China National Demonstration Center for Experimental Function Materials Education Tianjin 300384China

Issues like morphology control and further multifunctional applications are of significant importance for rare earth nano-oxides,e.g.,cerium dioxide(CeO_(2))nanostructures,however,relevant results in this respect are rather limited up to *** the present work,ultrathin CeO_(2) nanosheets were synthesized through a facile lowtemperature hydrothermal *** structure,morphology and specific surface area of these CeO_(2) nanosheets were characterized by X-ray diffraction(XRD),field emission scanning electron microscope(FESEM)and N2 ***,CeO_(2) nanosheets have the potential as bifunctional sensing materials to detect both humidity and formaldehyde *** CeO_(2) nanosheet humidity sensor exhibited excellent sensing characteristics in the relative humidity range of 11%-97% with the response value as high as 3.1×10^(4).Meanwhile,the CeO_(2) nanosheet gas sensor showed superior sensitivity and repeatability with fast response/recovery speed toward formaldehyde vapor at 300℃.Finally,the humidity and formaldehyde sensing mechanism were discussed as well.

关键词： CeO_(2)nanosheets Humidity sensor Gas sensor Formaldehyde

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Comparison of semi-coke with traditional pulverized coal injection and iron ore sintering fuels based on chemical structure and combustion behavior

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Journal of Iron and Steel Research International 2022年第5期29卷 725-740页

作者： Jiang-yong He Chong Zou Jun-xue Zhao Dong Liang Jia-le xi Cheng Ma School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an710311ShaanxiChina Technical Center of Shandong Iron and Steel Co. Ltd.(Laiwu Branch)Jinan271104ShandongChina

Substantial semi-coke has been produced through the industrialized low-temperature pyrolysis process,which has great potential as an alternative fuel for pulverized coal injection(PCI)and iron ore sintering.X-ray diffraction,Raman spectroscope,and thermal analysis were used to compare the carbon chemical structure and combustion reactivity of semi-coke,pulverized coal,and coke *** results show that the average volatile matter content in 46 types of semi-cokes is 8.94 wt.%.The fluctuation range of the characteristic parameters of the semi-coke chemical structure is d_(002)=(0.352–0.379)nm and A_(D1)/A_(G)=(2.51–7.92),while the fluctuation range of the characteristic parameters of pulverized coal is d_(002)=(0.348–0.373)nm and A_(D1)/A_(G)=(1.71–9.03)(where d_(002)means the interlayer spacing between the aromatic planes,and A_(D1)/A_(G)is an index that characterizes the degree of disorder of the char structure through the area ratio of the defect peak band D1 to the perfect graphite peak band G);the overlap between these ranges is relatively ***,the fluctuation range of the characteristic parameters of coke breeze is d_(002)=(0.343–0.350)nm and A_(D1)/A_(G)=(0.75–2.51),which is markedly different from that of ***-coke combustion reactivity is close to that of pulverized coal,but considerably better than that of coke *** terms of chemical structure and combustion reactivity,semi-coke can be used as an alternative fuel for PCI;however,when used for sintering alternative fuel,matching of the heat supply and demand in the later sintering stage must be scrupulously analyzed.

关键词： Semi-coke Coke Blast furnace Pulverized coal injection Combustion

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