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Explosion Event of Cavitation in Intact Xylem Conduit
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作者 Xingyue Li Fanyi Shen +4 位作者 Tiqiao Xiao Yanling Xue Li Zhang Rongfu Gao Qian Zhang 《Journal of Applied Mathematics and Physics》 2023年第10期2803-2315,共13页
Cavitation in plant conduits only involves two processes of air bubbles: the gradual expansion and elongation, and the explosion event. An explosion event of cavitation, which can only occur in intact conduit at water... Cavitation in plant conduits only involves two processes of air bubbles: the gradual expansion and elongation, and the explosion event. An explosion event of cavitation, which can only occur in intact conduit at water tension, trigs acoustic (or ultrasound) emission and induces air to diffuse with high speed, simultaneously. Synchrotron X-ray phase contrast microscopy (XPCM) was used to capture cavitation event in intact conduits of leaves of corn and rice. Cavitation events occur in certain areas of leaves and have a certain time frame. Before XPCM experiment, several preliminary experiments were done as follows: 1) Paraffin sections of leaves of different species were observed to select samples and to determine the occurrence area of cavitation event of leaves. 2) The time frame of cavitation occurrence was determined by ultrasonic emission. 3) The water potentials of leaves were determined, to know the water state of the leaves during cavitation. Locked the area and time frame of cavitation event in the leaves, consecutive XPCM images of cavitation process were more easily acquired. The images show that the phenomenon of gas bubble fully filling conduits for an instant took place in intact conduits of detached leaves of corn and rice more easily. It is that the gas diffusing in a moment was caused by the explosion of the air seeds which had entered in the intact conduits of the leaves. For living plants, it is suggested that the explosion event of cavitation is the most important for embolism formation. 展开更多
关键词 Synchrotron X-Ray Phase Contrast Microscopy Explosion Event CAVITATION Intact Conduit
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Research on the Degradation Kinetics Model in the Drying Process of Chinese Herb
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作者 任迪峰 毛志怀 王建中 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第6期822-825,共4页
Curative compositions such as catolpol in Rehmannia Glutinosa, flavone in Ophiopogon Japonicus and ginsenoside Re in Panax Ginseng in Chinese herbs were measured as the experimental indices by the method of high perfo... Curative compositions such as catolpol in Rehmannia Glutinosa, flavone in Ophiopogon Japonicus and ginsenoside Re in Panax Ginseng in Chinese herbs were measured as the experimental indices by the method of high performance liquid chromatography under different drying conditions. The reaction order and parameters of the degradation kinetics model were determined and the model was verified by experiments. It was indicated that by comparing with the thin drying method, the prospective model could predict the degradation of curative compositions with drying time, temperature and moisture content of herbal materials with enough precision and could be used to simulate the degradation in the drying process of Chinese herb. 展开更多
关键词 chinese herb DRYING degradation kinetics
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Molecular characterization of H3N2 and H4N6 subtypes avian influenza viruses isolated from mallards in Poyang Lake,China in 2010
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作者 ZHU Na ZHAO JiuRu +9 位作者 LI YongDong DING ChangQing XIA Han TANG Shuang ZHANG Zhong YU JingFeng CHEN Jing FAN ZhaoJun KOU Zheng LI TianXian 《Chinese Science Bulletin》 SCIE CAS 2012年第27期3586-3594,共9页
Poyang Lake is the largest inland freshwater lake in China and contains many species of wild birds and waterfowls.We conducted a survey of avian influenza viruses in nine semi-artificial waterfowl farms in Poyang Lake... Poyang Lake is the largest inland freshwater lake in China and contains many species of wild birds and waterfowls.We conducted a survey of avian influenza viruses in nine semi-artificial waterfowl farms in Poyang Lake during January to March of 2010.Out of 1036 cloacal swabs collected,three H3N2 and one H4N6 influenza viruses were isolated from healthy mallards.All the isolates were genetically and phylogenetically characterized.The analysis of putative HA cleavage sites showed that all the four isolates possessed the molecular characteristics(QTRGL for H3N2 viruses,PEKASR for H4N6 virus) of lowly pathogenic avian influenza(LPAI) virus.The phylogenetic analysis of the viral genomes showed that all four virus isolates clustered in the Eurasian clade of influenza viruses.The M gene of the viruses possessed the highest homology with highly pathogenic H5N1 influenza viruses.In addition,co-infection of H3N2 and H4N6 in the same farm was observed.And interestingly,we isolated two subtypes viruses(H3N2 and H4N6) and their progeny virus(H3N2) with evidence of genome reassortment from the same farm,in which the PB1 and PB2 gene segments of H4N6 replaced those of the H3N2 strain.The results of animal infection experiments showed that all the four isolated viruses were lowly pathogenic to chickens and not pathogenic to mice,which was consistent with the results of genetic analysis. 展开更多
关键词 禽流感病毒 病毒分离 分子特征 鄱阳湖 野鸭 亚型 中国 系统发育分析
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