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Measurement of solidprecipitation and blowing snow: current status and challenges

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Advances in Polar Science 2024年第3期35卷 289-302页

作者： PAN Rui liu xichuan SHI Jiayi College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China Key Laboratory of High Impact Weather(special) China Meteorological AdministrationChangsha 410073China

In this article,the relevant instruments and techniques for measuring solid precipitation and blowing snow are reviewed,with a focus on the in situ instrument ***,a literature review and specific observation activities for solid precipitation are provided,the working principles of several instruments are introduced,and the advantages and disadvantages,measurement performance,and specific application scenarios of the instruments are ***,there are numerous solid precipitation measurement instruments available,and the standardization and sustainability of these measurements also need to be *** purpose of the review is not to be exhaustive but to provide readers with information on the current status of the development of relevant technologies and the prospects for their application in the polar regions.

关键词： solid precipitation blowing snow measurement instruments

Optimized Synthesis of Carbon Aerogels via Ambient Pressure Drying Process as Electrode for Supercapacitors

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Journal of Wuhan University of Technology(Materials Science) 2015年第6期30卷 1325-1331页

作者：袁磊 CHANG Lijuan FU Zhibing YANG Xi JIAO Xingli TANG Yongjian liu xichuan 王朝阳 Science and Technology on Plasma Physics Laboratory Research Centre of Laser Fusion China Academy of Engineering Physics Institute of Atomic and Molecular Physics Sichuan University College of Material Science and Engineering Xihua University

Carbon aerogels were synthesized via ambient pressure drying process using resorcinolformaldehyde as precursor and P123 to strengthen their skeletons. CO2 activation technology was implemented to improve surface areas and adjust pore size distribution. The synthesis process was optimized, and the morphology, structure, adsorption properties and electrochemical behavior of different samples were characterized. The CO2-activated samples achieved a high specific capacitance of 129.2 F/g in 6 M KOH electrolytes at the current density of 1 m A/cm^2 within the voltage range of 0-0.8 V. The optimized activation temperature and duration were determined to be 950 ℃ and 4 h, respectively.

关键词： supercapacitors carbon aerogels ambient pressure drying process activation

Optimal Electrochemical Performances of CO_2 Activated Carbon Aerogels for Supercapacitors

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Journal of Wuhan University of Technology(Materials Science) 2014年第2期29卷 213-218页

作者：常丽娟 FU Zhibing liu Miao YUAN Lei WEI Jianjun HE Yong wei liu xichuan 王朝阳 Science and Technology on Plasma Physics Laboratory Institute of Atomic and Molecular Physics Sichuan University College of Material Science and Engineering Xihua University

Activated carbon aerogels（ACAs） derived from sol-gel polycondensation of resorcinol （R） and formaldehyde （F） were pyrolyzed under Ar flow and activated in CO2 atmosphere. The morphology of ACAs was characterized by scanning electron microscopy （SEM） and the structural properties were determined by N2 adsorption at 77 K. The results show that ACAs have a typical three-dimensional nanonetwork structure composing of cross-linking of carbon nanoparticles. The specific surface area and the total pore volume remarkably increase with increasing activation time while the previous porous structure still remains. The specific capacitance of the 950-10-ACA electrode can reach up to 212.3 F/g in 6 mol/L KOH electrolyte. The results of constant-current charge-discharge testing indicate that the ACAs electrodes present fast charge- discharge rate and long cycle life （about 98% capacitance retained after 3000 charge-discharge cycles at 1.25 mA/cm2）. Lower internal resistances can be achieved for 950-10-ACA electrode in KOH electrolyte. Our investigations are very important to improve the wettability and electrochemical performance of electrode for supercapacitors.

关键词： activated carbon aerogels specific surface area specific capacitance wettability cycling performance

The simulation and error analysis of raindrop size distribution obtained by micro rain radar

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Instrumentation 2015年第3期2卷 43-54页

作者： JIANG Shiyang GAO Taichang liu xichuan College of Meteorology and Oceanography PLA University of Science and Technology

Observation of raindrop size distribution( DSD) with a vertically pointing micro rain radar( MRR) has important significance in the precipitation measurement field. The Mie scattering of large particle,vertical wind and air turbulence have great influences on the retrieval of DSD measured by MRR. This paper simulates the process of how three factors affect the inversion of DSD and the calculation of other precipitation parameters,then makes the errors analysis. Because the wavelength of MRR is 12.5mm,M ie theory is more suitable for the precipitation particle than Rayleigh approximation,w hich may cause the underestimation of number density of small droplets and the overestimation of that in middle field. The vertical wind results in inaccurate estimation of particle terminal velocity,so the diameter is measured with some errors by empirical relationship,w hich affects the calculating accuracy of radar reflectivity and rain rate. Air turbulence can broaden the pow er spectral density,of which the impact on the inversion of DSD are concentrated in small droplets field. Then the measured data from MRR is analyzed and the results prove the impacts of those factors. Finally,according to the analysis and application limits,the prospect of the future research trend of particle size distribution is conducted.

关键词： DSD M ie theory the vertical wind air turbulence error analysis

Research on the calibration method of precipitation micro- physical characteristics sensor

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Instrumentation 2015年第3期2卷 55-64页

作者： SHU Xiaojian GAO Taichang liu xichuan HU Shuai College of Meteorology and Oceanography PLA University of Science and Technology

In order to diminish the effect of the ambient light and CCD pixel non-uniformity to the Precipitation Micro-physical Characteristics Sensor,a modified calibration scheme was designed and calibration experiments in sunny,cloudy,night,different location of sample space were carried out. Firstly,the characteristics of particle images which affected by ambient light and different location of sample space were analyzed. Secondly,the relevance betw een particle image features and parameters of image processing were discussed. Finally,the parameter setting scheme were determined,the radium of median filtering algorithm is 3 pixels,the defocusing radius of point spread function( PSF) is 7 pixels,the radium of erosion is 3 pixels,and the binary threshold is obtained from the Area-thresh relationship. The results show that the new scheme could deal with the image calibration well,the average errors of equivolumetric diameter was 0. 041 mm with standard deviation of 0. 115 mm,and the average errors of the axis ratio was 0. 011 with standard deviation of 0. 085. The new scheme works well in the field observation too,the observed axis ratio is consistent with the empirical relationship that proposed by Beard. The relative error of accumulation precipitation is-3. 06% after calibration,w hich is improved 1. 94% low er than the initial one without calibration.

关键词： precipitation micro-physical characteristics sensor calibration scheme particle image features threshold

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基于非球形雨滴的降雨对激光传输衰减的影响

红外与激光工程 2013年第1期42卷 167-173页

作者：刘西川高太长刘磊解放军理工大学气象海洋学院江苏南京211101

为了进一步确定降雨对激光在大气中传输衰减的影响,将雨滴的非球形效应考虑在内,在雨滴的近似椭球模型、归一化谱分布的基础上,利用射线追踪法计算群雨滴在可见光和近红外波段的散射和衰减特性,讨论分析雨滴谱分布和降雨强度对可见光和... 详细信息

为了进一步确定降雨对激光在大气中传输衰减的影响,将雨滴的非球形效应考虑在内,在雨滴的近似椭球模型、归一化谱分布的基础上,利用射线追踪法计算群雨滴在可见光和近红外波段的散射和衰减特性,讨论分析雨滴谱分布和降雨强度对可见光和近红外波段激光传输衰减的影响。数值模拟结果表明,不同谱分布的群雨滴散射能力从大到小依次为JD、MP、Gamma和JT分布;激光衰减不仅受降雨强度的影响,也与雨滴的数密度有关,数密度越大,激光衰减越大;而形状对群雨滴的影响较小。所得出的结论有助于准确评估降雨对激光传输的影响以及改善激光传输、通信和激光测风等应用。

关键词：激光传输衰减近似椭球雨滴雨滴谱分布射线追踪法

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自体肾上腺组织移植治疗大鼠截瘫

中国临床解剖学杂志 1994年第3期12卷 218-221页

作者： liu xichuan Wang Jian( Department of Physiology,Guangzhou Medical Collegt,Guangzhou 510182 广州医学院生理学教研室

研究的目的是观察移植自体肾上腺组织对大鼠在断脊髓神经再生与后肢运动功能恢复的作用。结果：低位横断移植组的肌力恢复率为９１．６％，低位横断对照组为２６．６％；高位横断移植组为４０％，高位横断对照组为０％。经Ｘ￣２测验，... 详细信息

研究的目的是观察移植自体肾上腺组织对大鼠在断脊髓神经再生与后肢运动功能恢复的作用。结果：低位横断移植组的肌力恢复率为９１．６％，低位横断对照组为２６．６％；高位横断移植组为４０％，高位横断对照组为０％。经Ｘ￣２测验，各组之间都有显著差异（Ｐ＜０．０５）。脊髓损伤部位有坏死、变性、囊腔与瘢痕等病理变化．在横断脊髓近端可见再生的轴突向远端延伸，并在伤处形成网络。对照组却无神经再生。在脊髓损伤处可见存活的移植肾上腺组织和长入其中的再生脊神经。结果提示移植的肾上腺组织可能诱发损伤脊髓神经再生和促进新的功能网络形成。

关键词：横断脊髓肾上腺移植神经再生

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新型人工岛护坡抗冰结构的系统设计与应用

中国海上油气 2012年第5期24卷 63-65,68页

作者：刘喜传中国海洋石油总公司

渤海湾冬季温度低,海冰结冰期长,大型冰块在环境驱动力的驱动下冲击人工岛护坡,危及油田工程和人身的安全,而现有的护坡结构形式很难满足特殊海况的要求,因此提出了一种新型人工岛护坡抗冰结构——伞型块体,并确定了这种新型护坡块体在... 详细信息

渤海湾冬季温度低,海冰结冰期长,大型冰块在环境驱动力的驱动下冲击人工岛护坡,危及油田工程和人身的安全,而现有的护坡结构形式很难满足特殊海况的要求,因此提出了一种新型人工岛护坡抗冰结构——伞型块体,并确定了这种新型护坡块体在不同水深下的技术使用参数。模型试验安装与现场应用结果表明,与现有的人工岛护坡结构相比,这种新型抗冰结构形式能够很好地抵抗大型冰块的冲击,经济性显著,具有很好的推广价值。

关键词：人工岛护坡抗冰结构设计渤海湾

15~23 GHz微波链路雨衰的敏感参量分析

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电子与信息学报 2021年第7期43卷 2007-2013页

作者：刘西川邹明忠张旭光国防科技大学气象海洋学院南京211101 江阴市河道管理处江阴214431 解放军32203部队华阴714200

为了提高微波链路雨衰特征的描述精度,拓展微波链路信号的可用参数,该文利用部署于江苏江阴地区的15 GHz,18 GHz和23 GHz微波链路和雨量计开展同步对比观测,拟合得到3种频段的微波链路雨衰关系。提取并分析了接收信号电平的平均值、中... 详细信息

为了提高微波链路雨衰特征的描述精度,拓展微波链路信号的可用参数,该文利用部署于江苏江阴地区的15 GHz,18 GHz和23 GHz微波链路和雨量计开展同步对比观测,拟合得到3种频段的微波链路雨衰关系。提取并分析了接收信号电平的平均值、中位数、25%分位数、75%分位数、标准差、极大值和极小值等13个特征量与晴雨时刻、降雨强度之间的关系,得出结论:微波链路的信号变化和降雨强度的变化存在明显的负相关关系。实际拟合的雨衰关系与ITU-R的经验雨衰关系具有较好的一致性,但是在不同频段上均有差异;所有13个参量在有雨时刻和无雨时刻均存在一定概率的重叠,这是造成晴雨区分困难的主要原因;频率越高,信号变化受降雨的影响越显著,越有利于微波链路反演降雨。所得出的结论为提高微波链路测雨方法中的晴雨区分、参考值确定以及雨强反演的精度提供重要依据。

关键词：微波链路降雨雨衰关系特征量