Some experimental investigations were carried out with the samples of metal Al and AlCl3 solutions. It is found that the spectrum varies with the change of experimental setup parameters both in Al bulk material and Al...Some experimental investigations were carried out with the samples of metal Al and AlCl3 solutions. It is found that the spectrum varies with the change of experimental setup parameters both in Al bulk material and AlCl3 solutions. The temporal evolution properties and the affection of incident laser energy on the laser-induced breakdown spectroscopy (LIBS) signals were also discussed. The lifetime of laser induced plasma in AlCl3 solutions is found to be about 30 ns which is much shorter than in solid materials. Compared with the solid samples, the Al LIBS signals in AlCl3 solutions require higher laser energy. Under the optimized conditions, the detection limit of Al in AlCl3 solution was determined to be around 1000 ppm for the system we used.展开更多
[ Objective] The aim was to analyze diurnal temperature range in Guigang from 1960 to 2009. [Method] Based on the conventional me- teorological data （mean daily temperature, mean maximum temperature, and mean minimum...[ Objective] The aim was to analyze diurnal temperature range in Guigang from 1960 to 2009. [Method] Based on the conventional me- teorological data （mean daily temperature, mean maximum temperature, and mean minimum temperature） of Guigang region during 1960 -2009, the Diurnal Temperature Range （DTR） and the DTR trend were studied. [ Result] The annual minimum temperatures and the annual maximum temperature were significantly increasing. The maximum temperature rose less than minimum temperature and spatial changes of daily temperature narrowed gradually from the Tropic of Cancer to the two sides. The extreme diurnal temperature decreased mostly in stations far away from the Tropic of Cancer and the significance was strong. The extreme diurnal temperature decreased little in stations close to the Tropic of Cancer. Influ- ences of different factors on daily difference varied. DTR positively correlated with sunshine duration, and negatively related to total cloudiness, rel- ative humidity and precipitation. DTR had insignificant relation with average wind speed. [ Conclusion] The study provided basis for the understand- ing of climate changes in Guigang.展开更多
水稻纹枯病是安陆市水稻主要病害之一,常年都有不同程度发生。尤其是2020年持续阴雨、寡照,水稻纹枯病在局部地区发生十分严重。24%噻呋酰胺悬浮剂防治水稻纹枯病防效显著,于水稻分蘖末期(7月5日)+水稻破口期(8月4日)施药两次,用24%噻...水稻纹枯病是安陆市水稻主要病害之一,常年都有不同程度发生。尤其是2020年持续阴雨、寡照,水稻纹枯病在局部地区发生十分严重。24%噻呋酰胺悬浮剂防治水稻纹枯病防效显著,于水稻分蘖末期(7月5日)+水稻破口期(8月4日)施药两次,用24%噻呋酰胺悬浮剂20 m L/667 m^(2)兑水30 kg均匀喷雾,齐穗时株防效、病指防效分别为80.2%、88.5%。符合试验要求,宜推广应用。展开更多
基金This work was supported by Hi-Tech Research and DevelopmentProgram of China (2002AA615170)Natural Science Foundationof Anhui (2001KJ116ZD)Natural Science Foundation ofShandong (Y2006A26)
文摘Some experimental investigations were carried out with the samples of metal Al and AlCl3 solutions. It is found that the spectrum varies with the change of experimental setup parameters both in Al bulk material and AlCl3 solutions. The temporal evolution properties and the affection of incident laser energy on the laser-induced breakdown spectroscopy (LIBS) signals were also discussed. The lifetime of laser induced plasma in AlCl3 solutions is found to be about 30 ns which is much shorter than in solid materials. Compared with the solid samples, the Al LIBS signals in AlCl3 solutions require higher laser energy. Under the optimized conditions, the detection limit of Al in AlCl3 solution was determined to be around 1000 ppm for the system we used.
基金Supported by The National Science and Technology Support Project (2007BAC29B02)The National Basic Research Program of China (2010CB428505)
文摘[ Objective] The aim was to analyze diurnal temperature range in Guigang from 1960 to 2009. [Method] Based on the conventional me- teorological data （mean daily temperature, mean maximum temperature, and mean minimum temperature） of Guigang region during 1960 -2009, the Diurnal Temperature Range （DTR） and the DTR trend were studied. [ Result] The annual minimum temperatures and the annual maximum temperature were significantly increasing. The maximum temperature rose less than minimum temperature and spatial changes of daily temperature narrowed gradually from the Tropic of Cancer to the two sides. The extreme diurnal temperature decreased mostly in stations far away from the Tropic of Cancer and the significance was strong. The extreme diurnal temperature decreased little in stations close to the Tropic of Cancer. Influ- ences of different factors on daily difference varied. DTR positively correlated with sunshine duration, and negatively related to total cloudiness, rel- ative humidity and precipitation. DTR had insignificant relation with average wind speed. [ Conclusion] The study provided basis for the understand- ing of climate changes in Guigang.
文摘水稻纹枯病是安陆市水稻主要病害之一,常年都有不同程度发生。尤其是2020年持续阴雨、寡照,水稻纹枯病在局部地区发生十分严重。24%噻呋酰胺悬浮剂防治水稻纹枯病防效显著,于水稻分蘖末期(7月5日)+水稻破口期(8月4日)施药两次,用24%噻呋酰胺悬浮剂20 m L/667 m^(2)兑水30 kg均匀喷雾,齐穗时株防效、病指防效分别为80.2%、88.5%。符合试验要求,宜推广应用。
