Smog chambers are the effective tools for studying formation mechanisms of air pollution.Simulations by traditional smog chambers differ to a large extent from real atmospheric conditions,including light,temperature a...Smog chambers are the effective tools for studying formation mechanisms of air pollution.Simulations by traditional smog chambers differ to a large extent from real atmospheric conditions,including light,temperature and atmospheric composition.However,the existing parameters for mechanism interpretation are derived from the traditional smog chambers.To address the gap between the traditional laboratory simulations and the photochemistry in the real atmosphere,a vehicle-mounted indoor-outdoor dual-smog chamber(JNUVMDSC)was developed,which can be quickly transferred to the desired sites to simulate quasi-realistic atmosphere simultaneously in both chambers using“local air”.Multiple key parameters of the smog chamber were characterized in the study,demonstrating that JNUVMDSC meets the requirements of general atmospheric chemistry simulation studies.Additionally,the preliminary results for the photochemical simulations of quasi-realistic atmospheres in Pearl River Delta region and Nanling Mountains are consistent with literature reports on the photochemistry in this region.JNU-VMDSC provides a convenient and reliable experimental device and means to study the mechanism of atmospheric photochemical reactions to obtain near-real results,and will make a great contribution to the control of composite air pollution.展开更多
This paper deals with investigations on corrosion of marble SO2. We have simulated oxidation of SO2 by photochemical process in the atmosphere. The experiments indicate that formation of SO3 aerosols is related to the...This paper deals with investigations on corrosion of marble SO2. We have simulated oxidation of SO2 by photochemical process in the atmosphere. The experiments indicate that formation of SO3 aerosols is related to the concentration of SO2, the UV light intensity, the time of irradiation and the humidity of the air. The corrosion feature of surfaces of the marble and the depth profiles of sulphur were obtained by SEM (Scanning electron microscope), EDXA (Energy-dispersive X-ray analyzer) and SIMS (Secondary ion mass spectrometer). The results of experiments show the corrosive extent of marble depends on its compositions and microareas of marble, which contain lower silicon content can be easily corroded by SO2.展开更多
Populus euphratica Oliv.is a unique woody tree that can be utilized for vegetation restoration in arid and semi-arid areas.The effects of saline water irrigation(0.00, 2.93, 8.78 and 17.55 g/L NaCl solutions) on water...Populus euphratica Oliv.is a unique woody tree that can be utilized for vegetation restoration in arid and semi-arid areas.The effects of saline water irrigation(0.00, 2.93, 8.78 and 17.55 g/L NaCl solutions) on water transport and water use efficiency(WUE) of P.euphratica saplings were researched for improving the survival of P.euphratica saplings and vegetation restoration in arid and semi-arid areas of Xinjiang, China in 2011.Results showed that hydraulic conductivity and vulnerability to cavitation of P.euphratica saplings were more sensitive in root xylem than in twig xylem when irrigation water salinity increased.Irrigation with saline water concentration less than 8.78 g/L did not affect the growth of P.euphratica saplings, under which they maintained normal water transport in twig xylem through adjustment of anatomical structure of vessels and kept higher WUE and photosynthesis in leaves through adjustment of stomata.However, irrigation with saline water concentration up to 17.55 g/L severely inhibited the photochemical process and WUE of P.euphratica saplings, resulting in severe water-deficit in leaves and a sharp reduction in water transport in xylem.Thus, it is feasible to irrigate P.euphratica forest by using saline groundwater for improving the survival of P.euphratica saplings and vegetation restoration in arid and semi-arid areas of Xinjiang, China.展开更多
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.41877370 and 42077190)the China Postdoctoral Science Foundation(No.2021M691229)+2 种基金the fund of Creative Research Groups of NSFC(No.42121004)the Science and Technology Planning Project of Guangdong Province of China(No.2019B121202002)the Guangdong Innovative and Entrepreneurial Research Team Program(No.2016ZT06N263).
文摘Smog chambers are the effective tools for studying formation mechanisms of air pollution.Simulations by traditional smog chambers differ to a large extent from real atmospheric conditions,including light,temperature and atmospheric composition.However,the existing parameters for mechanism interpretation are derived from the traditional smog chambers.To address the gap between the traditional laboratory simulations and the photochemistry in the real atmosphere,a vehicle-mounted indoor-outdoor dual-smog chamber(JNUVMDSC)was developed,which can be quickly transferred to the desired sites to simulate quasi-realistic atmosphere simultaneously in both chambers using“local air”.Multiple key parameters of the smog chamber were characterized in the study,demonstrating that JNUVMDSC meets the requirements of general atmospheric chemistry simulation studies.Additionally,the preliminary results for the photochemical simulations of quasi-realistic atmospheres in Pearl River Delta region and Nanling Mountains are consistent with literature reports on the photochemistry in this region.JNU-VMDSC provides a convenient and reliable experimental device and means to study the mechanism of atmospheric photochemical reactions to obtain near-real results,and will make a great contribution to the control of composite air pollution.
文摘This paper deals with investigations on corrosion of marble SO2. We have simulated oxidation of SO2 by photochemical process in the atmosphere. The experiments indicate that formation of SO3 aerosols is related to the concentration of SO2, the UV light intensity, the time of irradiation and the humidity of the air. The corrosion feature of surfaces of the marble and the depth profiles of sulphur were obtained by SEM (Scanning electron microscope), EDXA (Energy-dispersive X-ray analyzer) and SIMS (Secondary ion mass spectrometer). The results of experiments show the corrosive extent of marble depends on its compositions and microareas of marble, which contain lower silicon content can be easily corroded by SO2.
基金funded by the National Natural Science Foundation of China (U1703101, U1803101)the Science and the Strategic Priority Research Program of Chinese Academy of Sciences (XDA20100303)the Natural Science Foundation of Xinjiang Uygur Autonomous Region (2017D01A79)
文摘Populus euphratica Oliv.is a unique woody tree that can be utilized for vegetation restoration in arid and semi-arid areas.The effects of saline water irrigation(0.00, 2.93, 8.78 and 17.55 g/L NaCl solutions) on water transport and water use efficiency(WUE) of P.euphratica saplings were researched for improving the survival of P.euphratica saplings and vegetation restoration in arid and semi-arid areas of Xinjiang, China in 2011.Results showed that hydraulic conductivity and vulnerability to cavitation of P.euphratica saplings were more sensitive in root xylem than in twig xylem when irrigation water salinity increased.Irrigation with saline water concentration less than 8.78 g/L did not affect the growth of P.euphratica saplings, under which they maintained normal water transport in twig xylem through adjustment of anatomical structure of vessels and kept higher WUE and photosynthesis in leaves through adjustment of stomata.However, irrigation with saline water concentration up to 17.55 g/L severely inhibited the photochemical process and WUE of P.euphratica saplings, resulting in severe water-deficit in leaves and a sharp reduction in water transport in xylem.Thus, it is feasible to irrigate P.euphratica forest by using saline groundwater for improving the survival of P.euphratica saplings and vegetation restoration in arid and semi-arid areas of Xinjiang, China.