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超日冕距离矩阵谱的刻画技术 预览
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作者 许小静 王沛文 王志平 《工程数学学报》 CSCD 北大核心 2020年第2期215-230,共16页
图的拓扑结构在化学分子结构中有重要的意义,并且图的各种矩阵都蕴含了图的拓扑结构信息.在本文中,我们根据距离谱的定义以及四类图形的构造特点,对四类双日冕图进行了距离谱的刻画,通过数学归纳法得到对应的距离矩阵.在此基础上,本文... 图的拓扑结构在化学分子结构中有重要的意义,并且图的各种矩阵都蕴含了图的拓扑结构信息.在本文中,我们根据距离谱的定义以及四类图形的构造特点,对四类双日冕图进行了距离谱的刻画,通过数学归纳法得到对应的距离矩阵.在此基础上,本文构建了分块矩阵(超日冕距离矩阵),根据矩阵特征值的唯一性,对超日冕距离矩阵进行特征值以及特征向量的求解,并验证了结论准确性及可靠性.进一步,当G为完全图且G1,G2为正则图时,研究了四类特殊的双日冕图G(S)◦{G1,G2},G(Q)◦{G1,G2},G(R)◦{G1,G2},G(T)◦{G1,G2}的距离谱. 展开更多
关键词 日冕图 距离谱 双日冕图 超日冕距离矩阵
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A method of forced extrapolation of the global magnetic field in the solar corona
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作者 WANG Bing CHEN Yao +4 位作者 HU Qiang JIANG ChaoWei SONG HongQiang WU Zhao NING Hao 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2020年第2期234-242,共9页
We present a method of forced-field(i.e., non-force-free field: NFFF) extrapolation of the global magnetic field in the corona, on the basis of single-layer vector magnetogram, by extending an extrapolation technique ... We present a method of forced-field(i.e., non-force-free field: NFFF) extrapolation of the global magnetic field in the corona, on the basis of single-layer vector magnetogram, by extending an extrapolation technique of local magnetic field first developed by Hu et al.(2008). The forced coronal magnetic field is described by a system with the minimum dissipation rate(MDR) which is appropriate for the corona as a forced and open system. The obtained solution of the magnetic field can be decomposed into three components including one potential field and two linear force-free fields(LFFF). Starting from the given single-layer vector magnetogram, the bottom boundary condition for each component is determined with an iterative method to achieve a minimum difference of the transverse component between the extrapolated field and the original magnetogram. The final extrapolated forced field is given by the sum of the three component fields with the obtained bottom boundaries. The method is tested with an analytic magnetohydrostatic(MHS) solution. It is shown that the extrapolated forced field is highly consistent with the MHS solution at least from the solar disk to the heliocentric distance of 1.5 solar radii(R⊙). For instance, the complements of normalized and mean vector errors(E’n, E’m) are as high as ~97% and 95%, respectively. Further comparisons between magnetic strength, force and field line distributions indicate that the MHS solution has been successfully reconstructed. 展开更多
关键词 solar corona magnetic field forced extrapolation
Can Chinese Medicine Be Used for Prevention of Corona Virus Disease 2019 (COVID-19)? A Review of Historical Classics, Research Evidence and Current Prevention Programs
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作者 LUO Hui TANG Qiao-ling +4 位作者 SHANG Ya-xi LIANG Shi-bing YANG Ming Nicola Robinson LIU Jian-ping 《中国结合医学杂志:英文版》 SCIE CAS CSCD 2020年第4期243-250,共8页
Objective:Since December 2019,an outbreak of corona virus disease 2019(COVID-19)occurred in Wuhan,and rapidly spread to almost all parts of China.This was followed by prevention programs recommending Chinese medicine(... Objective:Since December 2019,an outbreak of corona virus disease 2019(COVID-19)occurred in Wuhan,and rapidly spread to almost all parts of China.This was followed by prevention programs recommending Chinese medicine(CM)for the prevention.In order to provide evidenee for CM recommendations,we reviewed ancient classics and human studies.Methods:Historical records on prevention and treatment of infections in CM classics,clinical evidence of CM on the prevention of severe acute respiratory syndrome(SARS)and H1N1 in flue nza,and CM preve ntion programs issued by health authorities in China since the COVID-19 outbreak were retrieved from differe nt databases and websites till 12 February,2020.Research evide nee in eluded data from clinical trials,cohort or other population studies using CM for preventing contagious respiratory virus diseases.Results:The use of CM to prevent epidemics of infectious diseases was traced back to ancient Chinese practice cited in Huangdi's Internal Classic(Huang Di Nei Jing)where preventive effects were recorded.There were 3 studies using CM for prevention of SARS and 4 studies for H1N1 influenza.None of the participants who took CM contracted SARS in the 3 studies.The infection rate of H1N1 in flue nza in the CM group was significantly lower than the non-CM group(relative risk 0.36,95%confidence interval 0.24-0.52;n=4).For prevention of COVID-19,23 provinces in China issued CM programs.The main principles of CM use were to tonify qi to protect from external pathoge ns,disperse wind and discharge heat,and resolve damp ness.The most frequently used herbs in eluded Radix astragali(Huangqi),Radix glycyrrhizae(Gancao),Radix saposhnikoviae(Fangfeng),Rhizoma Atractylodis Macrocephalae(Baizhu),Lonicerae Japonicae Flos(Jinyinhua),and Fructus forsythia(Lianqiao).Conclusions:Based on historical records and human evidenee of SARS and H1N1 influenza prevention,Chinese herbal formula could be an alternative approach for prevention of COVID-19 in high-risk population.Prospective,rigorous population stud 展开更多
关键词 Chinese medicine corona virus disease 2019(COVID-19) prevention program clinical evidence review
Theory about Treatments and Morbidity Prevention of Corona Virus Disease(Covid-19) 预览
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作者 Majid Rezaei Basiri 《药剂与药理学:英文版》 2020年第3期89-90,共2页
Corona virus is an enveloped virus from the category of RNA viruses.The patients are suffering from fever,cough,shortness of breath,and no definitive treatment or vaccine is currently available.The viral disease is gr... Corona virus is an enveloped virus from the category of RNA viruses.The patients are suffering from fever,cough,shortness of breath,and no definitive treatment or vaccine is currently available.The viral disease is gradually self-limiting due to the production of antibodies in the body.CDC has developed a new laboratory test kit for use in testing patient specimens for severe acute respiratory syndrome coronavirus,the virus that causes COVID-19.The test kit is called the Centers for Disease Control and Prevention(CDC)2019-Novel Coronavirus(2019-nCoV)Real-Time Reverse Transcriptase(RT)-PCR Diagnostic Panel.It seems traditional medicine would be usefulness to helping treatment of corona cuvid-19 patients too.It might be other screening distinguishes rapid tests with high detection limit by designing chines scientists are available[1-12]. 展开更多
关键词 Corona virus covid-19 patients PHYSICIANS traditional medicine TREATMENTS
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An ICME impact on the Martian hydrogen corona 预览
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作者 Qi Xu XiaoJun Xu +3 位作者 Qing Chang JiaYing Xu Jing Wang YuDong Ye 《地球与行星物理:英文版》 CSCD 2020年第1期38-44,共7页
The Martian hydrogen exosphere extends out of the bow shock, forming a "hydrogen corona". The solar wind interacts directly with the hydrogen corona. During an ICME event on 7 March 2015, the SWIA instrument... The Martian hydrogen exosphere extends out of the bow shock, forming a "hydrogen corona". The solar wind interacts directly with the hydrogen corona. During an ICME event on 7 March 2015, the SWIA instrument onboard Mars Atmosphere and Volatile Evolution mission (MAVEN) observed that the pick-up H+ fluxes in upstream solar wind were enhanced. Also increased were the penetrating H+ fluxes in the Martian atmosphere. Quantitatively, these penetrating H+ fluxes cannot increase by a factor of 5 simply due to a factor of 3 increase in the solar wind density, suggesting that the increased abundance of exospheric hydrogen upstream of the bow shock was a consequence of the passage of the ICME. A denser outer hydrogen corona at high altitudes suggests that the expansion of the neutral atmosphere was caused by the ICME. The excited and heated hydrogen exosphere probably indicates an elevated hydrogen escape rate during an ICME. 展开更多
关键词 MARS HYDROGEN CORONA ICME
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冲击电晕对输电线路过电压的畸变效应影响研究
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作者 李震宇 《电瓷避雷器》 CAS 北大核心 2019年第6期111-116,共6页
输电线路电晕能够消耗线路上过电压波的电磁能量,使得过电压波幅值衰减、波形畸变,有利于限制线路上的过电压水平。研究冲击电晕对线路过电压波的影响具有重要意义,为此本文建立了输电线路冲击电晕数学模型,用以研究电晕对输电线路暂态... 输电线路电晕能够消耗线路上过电压波的电磁能量,使得过电压波幅值衰减、波形畸变,有利于限制线路上的过电压水平。研究冲击电晕对线路过电压波的影响具有重要意义,为此本文建立了输电线路冲击电晕数学模型,用以研究电晕对输电线路暂态电压的畸变效应,该模型考虑了输电线路冲击电晕的物理特性。本文基于电晕伏安特性建立了一种电晕数学模型,并将其带入电磁场暂态分析软件(ATP/EMTP)中计算求解,通过在ATP软件中的用户定义功能研究电晕对输电线路过电压的畸变和衰减现象。比较计算结果与文献中的试验结果,结果表明:数学模型仿真计算结果与试验结果两者具有较好符合性。 展开更多
关键词 电晕 输电线路 过电压波形畸变 ATP/EMTP 电晕Q-V特性
On the Distance Spectra of Several Double Neighbourhood Corona Graphs
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作者 Xiaojing XU Zhiping WANG Jiaxue XU 《数学研究及应用:英文版》 CSCD 2019年第3期233-248,共16页
Let G be a connected graph of order n and D(G) be its distance matrix. The distance eigenvalues of G are the eigenvalues of its distance matrix. Its distance eigenvalues and their multiplicities constitute the distanc... Let G be a connected graph of order n and D(G) be its distance matrix. The distance eigenvalues of G are the eigenvalues of its distance matrix. Its distance eigenvalues and their multiplicities constitute the distance spectrum of G. In this article, we give a complete description of the eigenvalues and the corresponding eigenvectors of a block matrix DNC. Further, we give a complete description of the eigenvalues and the corresponding eigenvectors of distance matrix of double neighbourhood corona graphs G(S)· {G1, G2}, G(Q)· {G1, G2}, G(R)· {G1, G2},G(T)· {G1, G2}, where G is a complete graph and G1, G2 are regular graphs. 展开更多
关键词 CORONA DISTANCE spectrum DOUBLE neighbourhood CORONA GRAPH block matrix
The 6.7 keV Line Emission from the Stellar Flare of Algol 预览
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作者 Ambrose C. Eze Sudum Esaenwi Abraham I. Chima 《高能物理(英文)》 2019年第4期1090-1097,共8页
We present spectral analysis of Algol stellar flare data. The 2-day observation of Algol in our Galaxy was done by Suzaku Satellite. Algol binary system consists of two component stars that eclipse one another periodi... We present spectral analysis of Algol stellar flare data. The 2-day observation of Algol in our Galaxy was done by Suzaku Satellite. Algol binary system consists of two component stars that eclipse one another periodically. The stellar magnetic field activities and Roche Lobe overflow/mass transfer mechanisms during rapid rotation of the component stars generate an X-ray emission. The variation in brightness of the stellar flare from epoch to epoch provides useful information of stellar properties of the component stars. The atomic physics of the Kα line emission process in the vicinities of chromospherically active and X-ray flare stars, and binaries is well understood. The photo ionization/collisional excitation in the Algol’s corona produces 6.7 keV line emission. The accumulated spectra in X-ray Imaging Spectrometer (XIS) sensors fitted combined with bremsstrahlung model and Gaussian line show a strong fixed X-ray energy of 6.7 keV. 展开更多
关键词 FLARE STARS Active ECLIPSING Binary Algol CORONA STELLAR FLARE X-Ray Line Emission
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±1100 kV线路金具电场仿真与电晕特性 被引量:1
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作者 毛艳 邓桃 +2 位作者 魏杰 牛海军 张学军 《高电压技术》 EI CAS CSCD 北大核心 2019年第4期1137-1145,共9页
±1 100 kV直流工程将采用8×1 250 mm2大截面导线,与导线配套的线路金具的电晕特性是工程设计及运行必须考虑的问题,特别是悬垂线夹、间隔棒线夹以及防振锤锤头处极易发生电晕,在防晕设计时必须足够重视。应用三维有限元电场... ±1 100 kV直流工程将采用8×1 250 mm2大截面导线,与导线配套的线路金具的电晕特性是工程设计及运行必须考虑的问题,特别是悬垂线夹、间隔棒线夹以及防振锤锤头处极易发生电晕,在防晕设计时必须足够重视。应用三维有限元电场仿真计算软件,开展了±1 100 kV直流输电线路420 kN单联双节V型悬垂串、550 kN六联三挂点绝缘子耐张串及档中金具和鼠笼式刚性跳线的电场仿真计算,获得了线路各金具表面最大场强值。依托昌平特高压直流试验基地,开展了单联单挂点悬垂串、六联耐张串、鼠笼式刚性跳线、防振锤、导线间隔棒等真型金具的可见电晕试验。电场仿真和试验结果表明,悬垂串和耐张串用均压/屏蔽环管径为150mm、间隔棒线夹曲率半径为27 mm、防振锤锤头曲率半径为40 mm的设计基本能满足2 500 m以下海拔的±1 100 kV特高压直流工程防晕设计要求。研究成果已应用于国内第1条昌吉—古泉±1 100 kV直流输电线路工程设计中。 展开更多
关键词 ±1 100 kV线路金具 均压/屏蔽环 间隔棒 悬垂线夹 防振锤 电场 电晕
针板缺陷下局部放电的严重程度分析
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作者 滕开雯 张弛 +5 位作者 徐轩 单秉亮 何金 王华威 李小叶 黄猛 《水电能源科学》 北大核心 2019年第7期167-171,共5页
高压开关柜在输配电系统的开关控制中起着至关重要的作用,通过状态监测识别其缺陷严重程度具有重要的工程意义。根据开关柜的常见放电情形,设计了模拟尖刺放电的针板缺陷模型,通过逐步升压法研究了局部放电图谱随缺陷严重程度的变化规律... 高压开关柜在输配电系统的开关控制中起着至关重要的作用,通过状态监测识别其缺陷严重程度具有重要的工程意义。根据开关柜的常见放电情形,设计了模拟尖刺放电的针板缺陷模型,通过逐步升压法研究了局部放电图谱随缺陷严重程度的变化规律,并通过简化模型定量分析了局部放电发展过程中的电荷运动和电场分布规律。结果表明,该模型可有效刻画缺陷严重程度演变的本质,并提供了一种基于局部放电图谱的判别依据。研究成果可应用于实际工程中。 展开更多
关键词 开关柜 局部放电 针板缺陷 流注 电晕
交直流输电线路离子流场的时域混合有限元法 预览
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作者 田毅 黄新波 +4 位作者 田文超 曹雯 朱永灿 赵隆 张烨 《电机与控制学报》 EI CSCD 北大核心 2019年第10期85-94,共10页
高压交、直流输电线路同走廊架设作为一种提高走廊输电能力和节约土地资源的方法得到大力发展。两种线路相互接近时,其电磁环境与交直流线路单独运行时是不同的,因此需要对混合场进行分析从而指导混合线路的设计。在分析混合线路离子流... 高压交、直流输电线路同走廊架设作为一种提高走廊输电能力和节约土地资源的方法得到大力发展。两种线路相互接近时,其电磁环境与交直流线路单独运行时是不同的,因此需要对混合场进行分析从而指导混合线路的设计。在分析混合线路离子流场中,第一次将时域混合有限元法应用于混合离子流场的数值模拟。此外,在数值模拟中高压直流和交流输电线路之间的相互作用被考虑。通过与实测结果以及现有方法相比,证明了所提方法更加适合交、直流线路混合离子流场问题的分析,并且在提高计算效率和精确度的同时获得了无震荡数值解。对不同混合线路配置模型的地面电场和离子流密度进行了数值模拟,通过分析计算结果,总结了混合输电线路电场分布的一般规律。最后,利用所提数值模拟方法对两种典型的全尺寸同走廊输电线路模型进行了分析,进而为工程设计提供参考。 展开更多
关键词 混合线路 离子流场 电晕 时域混合有限元法 电场分布
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两类冠图的Randi■能量 预览
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作者 付飞琴 邵燕灵 《华中师范大学学报:自然科学版》 CAS CSCD 北大核心 2019年第4期474-477,486共5页
设G是顶点集为V(G)={v1,v2,…,vn}的简单无向图,R(G)=(rij)是图G的Randi■矩阵,其中当vi与vj相邻时rij=1/■;否则rij=0.图G的Randi■能量RE(G)指R(G)的特征值的绝对值之和.冠图G■1G2是由图G1的每个顶点与图G2的一个拷贝的所有顶点相连... 设G是顶点集为V(G)={v1,v2,…,vn}的简单无向图,R(G)=(rij)是图G的Randi■矩阵,其中当vi与vj相邻时rij=1/■;否则rij=0.图G的Randi■能量RE(G)指R(G)的特征值的绝对值之和.冠图G■1G2是由图G1的每个顶点与图G2的一个拷贝的所有顶点相连得到的.本文对冠图Ir(Kn)和K■nKm的Randi■能量进行了研究. 展开更多
关键词 Randi■矩阵 Randi■能量 冠图 图谱
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Dynamic changes of protein corona compositions on the surface of zinc oxide nanoparticle in cell culture media
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作者 Vo-Van Giau Yoon-Hee Park +2 位作者 Kyu-Hwan Shim Sang-Wook Son Seong-Soo A. An 《化学科学与工程前沿:英文版》 EI CAS CSCD 2019年第1期90-97,共8页
The potential applications of nanomaterials used in nanomedicine as ingredients in drug delivery systems and in other products continue to expand. When nanomaterials are introduced into physiological environments and ... The potential applications of nanomaterials used in nanomedicine as ingredients in drug delivery systems and in other products continue to expand. When nanomaterials are introduced into physiological environments and driven by energetics, they readily associate proteins forming a protein corona (PC) on their surface. This PC could result in an alteration of the nanomatcrial's surface characteristics, affecting their interaction with cells due to conformational changes in adsorbed protein molecules. However, our current understanding of nanobiological interactions is still very limited. Utilizing a liquid chromatography-mass spectroscopy/mass spectroscopy technology and a Cytoscape plugin (ClueGO) approach, we examined the composition of the PC for a set of zinc oxide nanoparticles (ZnONP) from cell culture media typically and further analyzed the biological interaction of identified proteins, respectively. In total, 36 and 33 common proteins were investigated as being bound to ZnONP at 5 min and 60 min, respectively. These proteins were further analyzed with ClueGO, a Cytoscape plugin, which provided gene ontology and the biological interaction processes of identified proteins. Proteins bound to the surface of nanoparticles that may modify the structure, therefore the function of the adsorbed protein could be consequently affect the complicated biological processes. 展开更多
关键词 ZnONPs NANOPARTICLES PROTEIN CORONA ClueGO
基于脉冲电流法的低频与工频电压下油中电晕放电特性对比研究 预览
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作者 周远翔 周仲柳 +2 位作者 郭绍伟 牛铮 张灵 《电工技术学报》 EI CSCD 北大核心 2019年第1期160-169,共10页
对于电容量较大设备的局部放电试验,采用低频电压代替工频电压可有效降低对试验电源的容量需求。低频电压下试验结果的有效性需要考核,为探究电压频率对绝缘油中电晕放电特性的影响,基于脉冲电流法开展了工频50Hz到低频5Hz下油中尖板电... 对于电容量较大设备的局部放电试验,采用低频电压代替工频电压可有效降低对试验电源的容量需求。低频电压下试验结果的有效性需要考核,为探究电压频率对绝缘油中电晕放电特性的影响,基于脉冲电流法开展了工频50Hz到低频5Hz下油中尖板电极的放电试验。研究结果表明,油中电晕放电的一些基本特性在低频电压下未改变,即正半周放电量明显大于负半周,放电分布在电压峰值附近,呈尖峰状。差异性主要是低频下尖峰特点趋于模糊;随着频率的下降,起始电压稍有上升;正、负半周放电停止相位提前,最大放电量、平均放电量与脉冲重复率整体呈下降趋势;各频率下放电相位分布图谱(PRPD)与统计图谱(qmean-φ、qmax-φ、n-φ与n-q)整体形状一致,但分布范围不同;统计图谱的部分分布特征参数有明显变化。试验结果可作为低频电压下局部放电模式识别的参考。与传统只用50Hz电压进行试验对比,放电统计量随频率的变化趋势也提供了有关绝缘缺陷的更多信息。 展开更多
关键词 电晕 低频电压 脉冲电流法 局部放电图谱 统计参数
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高压开关柜放电腐蚀分析及改进措施 预览
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作者 尚德良 《冶金设备管理与维修》 2019年第1期46-47,50共3页
分析了35kV高压开关柜铜母线腐蚀的问题,采取了必要的应对措施后使该问题得到解决。
关键词 电晕 结露 腐蚀 嗅氧
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Prototype of highly efficient liquid electrode pulsating corona plasma reactor for degradation of organics in water
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作者 Sa?a RAN?EV Milica PETROVI? +3 位作者 Dragan RADIVOJEVI? Aleksandar BOJI? ?edomir MALUCKOV Miodrag RADOVI? 《等离子体科学与技术:英文版》 SCIE EI CAS CSCD 2019年第12期67-77,共11页
Prototype of atmospheric pressure non-thermal corona plasma reactor, developed for degradation of organics in water, operates at significantly higher frequency than other reactors for that purpose, and without sparks.... Prototype of atmospheric pressure non-thermal corona plasma reactor, developed for degradation of organics in water, operates at significantly higher frequency than other reactors for that purpose, and without sparks. Its construction provides the umbrella shaped, sustained pulsating corona discharge, with defined discharge oscillations on a given pulse frequency above the water surface. Dye degradation rate decreases with the decrease of discharge current density. Plasmaformed H2O2 is consumed in dye degradation. The energy yield of dye degradation is 2.45 g k Wh^-1 for 50 ppm solution, which is higher than in other publications for comparable experimental conditions. 展开更多
关键词 CORONA pulsating frequency DEGRADATION
Characteristics and underlying physics of ionic wind in dc corona discharge under different polarities
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作者 张桐恺 张宇 +2 位作者 季启政 李犇 欧阳吉庭 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第7期324-332,共9页
During a dc corona discharge, the ions’ momentum will be transferred to the surrounding neutral molecules, inducing an ionic wind.The characteristics of corona discharge and the induced ionic wind are investigated ex... During a dc corona discharge, the ions’ momentum will be transferred to the surrounding neutral molecules, inducing an ionic wind.The characteristics of corona discharge and the induced ionic wind are investigated experimentally and numerically under different polarities using a needle-to-ring electrode configuration.The morphology and mechanism of corona discharge, as well as the characteristics and mechanism of the ionic wind, are different when the needle serves as cathode or anode.Under the different polarities of the applied voltage, the ionic wind velocity has a linear relation with the overvoltage.The ionic wind is stronger but has a smaller active region for positive corona compared to that for negative corona under a similar condition.The involved physics are analyzed by theoretical deduction as well as simulation using a fluid model.The ionic wind of negative corona is mainly affected by negative ions.The discharge channel has a dispersed feature due to the dispersed field, and therefore the ionic wind has a larger active area.The ionic wind of positive corona is mainly affected by positive ions.The discharge develops in streamer mode, leading to a stronger ionic wind but a lower active area. 展开更多
关键词 CORONA DISCHARGE IONIC wind ELECTRODE polarity
Naphthalene oxidation by different nonthermal electrical discharges at atmospheric pressure
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作者 M REDOLFI N BLIN-SIMIAND +2 位作者 X DUTEN S PASQUIERS K HASSOUNI 《等离子体科学与技术:英文版》 SCIE EI CAS CSCD 2019年第5期151-161,共11页
Gaseous naphthalene has been removed by air plasma generated by pulsed corona discharges at 100°C(LSPM)and dielectric barrier discharges(DBD)up to 250℃(LPGP)in different reactors geometries.Naphthalene has been ... Gaseous naphthalene has been removed by air plasma generated by pulsed corona discharges at 100°C(LSPM)and dielectric barrier discharges(DBD)up to 250℃(LPGP)in different reactors geometries.Naphthalene has been chosen as one of unbumed hydrocarbon present in exhaust gas engine during the cold start of vehicles.The comparison between the different discharge geometries has been possible using the specific input energy(SIE)as relevant parameter for pollutant removal process control considering the differences in the electrical characteristics and the differences of gas flow.The best naphthalene degradation is obtained in the wire-to cylinder(WTC)corona discharge and the stem-to-cylinder DBD with an energy costβrespectively of 10 and 20 J L^-1.The main by-products issues of the naphthalene oxidation are CO2 and CO reaching 45%in Multi-Pin-to-Plan corona discharge.We detected polyaromatic hydrocarbons in the gas phase(few ppm)and in the solid phase deposited in the reactors.The introduction of water in the discharges promotes the naphthalene degradation by OH-atom,which has better oxidising power than O-atom in dry air. 展开更多
关键词 CORONA discharges DBD naphtalene engine EMISSIONS
日盲紫外波段电晕成像特性的仿真研究 预览
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作者 王颢 王璐子 +3 位作者 倪进园 王洪刚 王岩 钱芸生 《红外技术》 CSCD 北大核心 2019年第11期1057-1064,共8页
由于国内对紫外的视景仿真研究较少,本文提出了一种基于日盲紫外波段的电晕成像仿真方法。该方法研究了试验电压和探测距离对绝缘子缺陷电晕放电的紫外光子计数的影响,提出了改进的经验公式。提出了利用像素点对应紫外光子仿真电晕放电... 由于国内对紫外的视景仿真研究较少,本文提出了一种基于日盲紫外波段的电晕成像仿真方法。该方法研究了试验电压和探测距离对绝缘子缺陷电晕放电的紫外光子计数的影响,提出了改进的经验公式。提出了利用像素点对应紫外光子仿真电晕放电的算法,得到了电晕放电的紫外仿真图像。通过在vieWTerra视景仿真平台中建立绝缘子模型,获得了可见光图像。将可见光图像和紫外图像通过加权平均图像融合方法进行融合,得到日盲紫外波段的电晕成像仿真图,为研究日盲紫外视景仿真提供了参考。 展开更多
关键词 日盲紫外 紫外光子 电晕 视景仿真 图像融合
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The Normalized Laplacian Spectrum of Subdivision Vertex-Edge Corona for Graphs
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作者 Muchun LI You ZHANG Fei WEN 《数学研究及应用:英文版》 CSCD 2019年第3期221-232,共12页
A subdivision vertex-edge corona G1S?(∪ G3E) is a graph that consists of S(G1),|V(G1)| copies of G2 and |I(G1)| copies of G3 by joining the i-th vertex in V(G1) to each vertex in the i-th copy of G2 and i-th vertex o... A subdivision vertex-edge corona G1S?(∪ G3E) is a graph that consists of S(G1),|V(G1)| copies of G2 and |I(G1)| copies of G3 by joining the i-th vertex in V(G1) to each vertex in the i-th copy of G2 and i-th vertex of I(G1) to each vertex in the i-th copy of G3.In this paper, we determine the normalized Laplacian spectrum of G1S?(G2V∪ G3E) in terms of the corresponding normalized Laplacian spectra of three connected regular graphs G1, G2 and G3. As applications, we construct some non-regular normalized Laplacian cospectral graphs. In addition, we also give the multiplicative degree-Kirchhoff index, the Kemeny’s constant and the number of the spanning trees of G1S?(G2V∪ G3E) on three regular graphs. 展开更多
关键词 normalized Laplacian spectrum cospectral GRAPHS SPANNING trees SUBDIVISION vertex-edge CORONA
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