Knowledge of the statistical characteristics of inversions and their effects on aerosols under different large-scale synoptic circulations is important for studying and modeling the diffusion of pollutants in the boun...Knowledge of the statistical characteristics of inversions and their effects on aerosols under different large-scale synoptic circulations is important for studying and modeling the diffusion of pollutants in the boundary layer. Based on results gen- erated using the self-organizing map （SOM） weather classification method, this study compares the statistical characteristics of surface-based inversions （SBIs） and elevated inversions （EIs）, and quantitatively evaluates the effect of SBIs on aerosol condensation nuclei （CN） concentrations and the relationship between temperature gradients and aerosols for six prevailing synoptic patterns over the the Southern Great Plains （SGP） site during 2001-10. Large-scale synoptic patterns strongly influ- ence the statistical characteristics of inversions and the accumulation of aerosols in the low-level atmosphere. The activity, frequency, intensity, and vertical distribution of inversions are significantly different among these synoptic patterns. The verti- cal distribution of inversions varies diurnally and is significantly different among the different synoptic patterns. Anticyclonic patterns affect the accumulation of aerosols near the ground more strongly than cyclonic patterns. Mean aerosol CN con- centrations increase during SBIs compared to no inversion cases by 16.1%, 22.6%, 24.5%, 58.7%, 29.8% and 23.7% for the six synoptic patterns. This study confirms that there is a positive correlation between temperature gradients and aerosol CN concentrations near the ground at night under similar large-scale synoptic patterns. The relationship is different for different synoptic patterns and can be described by linear functions. These findings suggest that large-scale synoptic patterns change the static stability of the atmosphere and inversions in the lower atmosphere, thereby influencing the diffusion of aerosols near the ground.展开更多
用自燃烧法低温合成了单相 (Sr,Pb) Ti O3陶瓷粉末 ,研究和确定了自燃烧反应的 p H值条件 ,分析了自燃烧反应历程。测量了 (Sr,Pb) Ti O3的居里温度及 Y掺杂陶瓷阻 -温特性。结果表明 ,(Sr,Pb) Ti O3的居里温度较理论计算值稍有偏移。...用自燃烧法低温合成了单相 (Sr,Pb) Ti O3陶瓷粉末 ,研究和确定了自燃烧反应的 p H值条件 ,分析了自燃烧反应历程。测量了 (Sr,Pb) Ti O3的居里温度及 Y掺杂陶瓷阻 -温特性。结果表明 ,(Sr,Pb) Ti O3的居里温度较理论计算值稍有偏移。典型陶瓷样品的电阻升阻比为 4.2 ,V型特性明显。Y掺杂陶瓷样品的电阻率与 Y掺杂量之间关系符合一般稀土掺杂规律。展开更多
基金sponsored by the U.S. Department of Energy (DOE)supported by the Ministry of Science and Technology of China (Grant Nos. 2010CB950804 and 2013CB955801)+1 种基金the "Strategic Priority Research Program" of the Chinese Academy of Sciences (Grant No. XDA05100300)the National Natural Science Foundation of China (Grant No. 41305011)
文摘Knowledge of the statistical characteristics of inversions and their effects on aerosols under different large-scale synoptic circulations is important for studying and modeling the diffusion of pollutants in the boundary layer. Based on results gen- erated using the self-organizing map （SOM） weather classification method, this study compares the statistical characteristics of surface-based inversions （SBIs） and elevated inversions （EIs）, and quantitatively evaluates the effect of SBIs on aerosol condensation nuclei （CN） concentrations and the relationship between temperature gradients and aerosols for six prevailing synoptic patterns over the the Southern Great Plains （SGP） site during 2001-10. Large-scale synoptic patterns strongly influ- ence the statistical characteristics of inversions and the accumulation of aerosols in the low-level atmosphere. The activity, frequency, intensity, and vertical distribution of inversions are significantly different among these synoptic patterns. The verti- cal distribution of inversions varies diurnally and is significantly different among the different synoptic patterns. Anticyclonic patterns affect the accumulation of aerosols near the ground more strongly than cyclonic patterns. Mean aerosol CN con- centrations increase during SBIs compared to no inversion cases by 16.1%, 22.6%, 24.5%, 58.7%, 29.8% and 23.7% for the six synoptic patterns. This study confirms that there is a positive correlation between temperature gradients and aerosol CN concentrations near the ground at night under similar large-scale synoptic patterns. The relationship is different for different synoptic patterns and can be described by linear functions. These findings suggest that large-scale synoptic patterns change the static stability of the atmosphere and inversions in the lower atmosphere, thereby influencing the diffusion of aerosols near the ground.
文摘用自燃烧法低温合成了单相 (Sr,Pb) Ti O3陶瓷粉末 ,研究和确定了自燃烧反应的 p H值条件 ,分析了自燃烧反应历程。测量了 (Sr,Pb) Ti O3的居里温度及 Y掺杂陶瓷阻 -温特性。结果表明 ,(Sr,Pb) Ti O3的居里温度较理论计算值稍有偏移。典型陶瓷样品的电阻升阻比为 4.2 ,V型特性明显。Y掺杂陶瓷样品的电阻率与 Y掺杂量之间关系符合一般稀土掺杂规律。
