The aerosol optical properties and chemical components of PM2.1(particulate matter with a diameter of 2.1μm or less)were investigated at Mount Gongga on the eastern slope of the Tibetan Plateau from April 2012 to Dec...The aerosol optical properties and chemical components of PM2.1(particulate matter with a diameter of 2.1μm or less)were investigated at Mount Gongga on the eastern slope of the Tibetan Plateau from April 2012 to December 2014.The annual mean aerosol optical depth(AOD)was 0.35±0.23,and the?ngstr?m exponent was 1.0±0.38.The AOD exhibited higher values in summer and winter,but lower values in spring and autumn.Dividing the observational periods into dry and wet seasons,the authors found that the concentrations of K^+,elemental carbon,secondary inorganic aerosols,and primary and secondary organic carbon in the dry(wet)season were 0.29(0.21),0.88(0.60),7.4(4.5),7.5(5.1),and 3.9(12)μg m?3,respectively.Combined with trajectory analysis,the authors found that higher concentrations of K^+,elemental carbon,and primary organic carbon indicated the effects of biomass burning from Southeast Asia during the dry season.However,the oxidation of volatile organic compounds was the main source of aerosols during the wet season,which originated from the Sichuan Basin.展开更多
Let D be an integral domain and X an indeterminate over D . We show that if S is an almost splitting set of an integral domain D , then D is an APVMD if and only if both DS and DN(S) are APVMDs. We also prove that if...Let D be an integral domain and X an indeterminate over D . We show that if S is an almost splitting set of an integral domain D , then D is an APVMD if and only if both DS and DN(S) are APVMDs. We also prove that if {Dα}α∈I is a collection of quotient rings of D such that D=∩α∈IDα has finite character (that is, each nonzero d∈D is a unit in almost all Dα) and each of Dα is an APVMD, then D is an APVMD. Using these results, we give several Nagata-like theorems for APVMDs.展开更多
基金supported by the National Basic Research Program of China[grant numbers 2016YFC0202001 and 973Program 2014CB441200]the National Natural Science Foundation of China[grant numbers 41375036 and41305076]
文摘The aerosol optical properties and chemical components of PM2.1(particulate matter with a diameter of 2.1μm or less)were investigated at Mount Gongga on the eastern slope of the Tibetan Plateau from April 2012 to December 2014.The annual mean aerosol optical depth(AOD)was 0.35±0.23,and the?ngstr?m exponent was 1.0±0.38.The AOD exhibited higher values in summer and winter,but lower values in spring and autumn.Dividing the observational periods into dry and wet seasons,the authors found that the concentrations of K^+,elemental carbon,secondary inorganic aerosols,and primary and secondary organic carbon in the dry(wet)season were 0.29(0.21),0.88(0.60),7.4(4.5),7.5(5.1),and 3.9(12)μg m?3,respectively.Combined with trajectory analysis,the authors found that higher concentrations of K^+,elemental carbon,and primary organic carbon indicated the effects of biomass burning from Southeast Asia during the dry season.However,the oxidation of volatile organic compounds was the main source of aerosols during the wet season,which originated from the Sichuan Basin.
基金National Natural Science Foundation of China (Grant No. 11171240)Fundamental Research Funds for the Central Universities,Southwest University for Nationalities (Grant No. 11NZYQN24)
文摘Let D be an integral domain and X an indeterminate over D . We show that if S is an almost splitting set of an integral domain D , then D is an APVMD if and only if both DS and DN(S) are APVMDs. We also prove that if {Dα}α∈I is a collection of quotient rings of D such that D=∩α∈IDα has finite character (that is, each nonzero d∈D is a unit in almost all Dα) and each of Dα is an APVMD, then D is an APVMD. Using these results, we give several Nagata-like theorems for APVMDs.
