Aerosol optical properties from August 2006 to July 2007 were obtained from ground-based and sky radiance measurements in Semi- Arid Climate and Environment Observatory of Lanzhou University （SACOL）, China. High aer...Aerosol optical properties from August 2006 to July 2007 were obtained from ground-based and sky radiance measurements in Semi- Arid Climate and Environment Observatory of Lanzhou University （SACOL）, China. High aerosol optical thickness （AOT） associated with low .Angstrom exponent （α） was mainly observed in spring, which was consistent with the seasonal dust production from Hexi Corridor. The maximum monthly average value of AOT 0.56 occurred in March of 2007, which was two times larger than the minimum value of 0.28 in October of 2006. Approximately 60% of the AOT ranged between 0.3 and 0.5, and nearly 93% ofα value varied from 0.1 to 0.8, which occurred in spring. The significant correlation between aerosol properties and water vapor content was not observed. The aerosol volume size distribution can be characterized by the bimodal logarithm normal structure： fine mode （r 〈 0.6 μm） and coarse mode （r 〉 0.6 μm）. Aerosols in spring of SACOL were dominated by large particles with the volume concentration ratio of coarse to fine modes being 7.85. The average values of asymmetry factor （g） in the wavelength range 440-1020 nm were found to be 0.71, 0.67, 0.67 and 0.69 in spring, summer, autumn and winter, respectively.展开更多
A comprehensive agricultural inventory of ammonia emissions for 2017 in Hefei was established on the basis of the specific emission factors and county-level activity data.The emissions over a 1 km×1 km grid and t...A comprehensive agricultural inventory of ammonia emissions for 2017 in Hefei was established on the basis of the specific emission factors and county-level activity data.The emissions over a 1 km×1 km grid and the associated monthly variations were distributed on the basis of land-use type and meteorological conditions,respectively.The total ammonia emissions were 27,242.7 t in 2017 in Hefei,to which livestock was the top contributor,accounting for 54.5%.Two major contributors to livestock waste were broilers and laying hens,which contributed 34.5%and 22.2%of the total emissions,respectively.Changfeng,Feixi,and Feidong counties,with more developed agriculture than other counties,accounted for a large proportion of the total ammonia emissions—as much as 28.5%,24.5%,and 21.0%,respectively.The average emissions density of the whole region was 2.4 t km−2,and the higher values were mostly in areas with denser populations.Seasonally,peak ammonia emissions occurred in summer.展开更多
The variations of sulfate formation and optical coefficients during SO2 heterogeneous reactions on hematite surface under different SO2 concentrations were examined using in situ diffuse reflectance infrared Fourier t...The variations of sulfate formation and optical coefficients during SO2 heterogeneous reactions on hematite surface under different SO2 concentrations were examined using in situ diffuse reflectance infrared Fourier transform spectroscopy （DRIFTS） and ion chromatograph （IC）. Laboratory experiments revealed that within ambient SO2 of 0.51-18.6 ppmv, sulfate product, producing velocity, absorption and backward scattering coefficients showed an increasing trend with SO2 concentration. Under given SO2 concentration, the velocity of sulfate producing performed an evolution of initial increasing, midterm decreasing and final stabilizing. The reactive uptake and Brunaner-Emmett-Teller （BET） uptake coefficients of heterogeneous reactions rose with SOz and exhibited high reactivities. Considering global warming, this result is important for the knowledge of heterogeneous reactions of SO2 on mineral particle surface in the atmosphere and the assessment of their impacts on radiative forcing.展开更多
基金supported by the National Basic Research Program (973) of China (No. 2006CB403706)the National Natural Science Foundation of China (No.40875078)+2 种基金the Key Basic Research Program of Natural Science for University of Jiangsu (No. 08KJA170002)the Key Laboratory of Meteorological Disaster of Ministry of Education, Nanjing University of Information Scienceand Technology (No. KLME20060302, KLME060209,KLME0907)the Shanghai Tongji Gao Tingyao Environmental Science & Technology Development Foundation
文摘Aerosol optical properties from August 2006 to July 2007 were obtained from ground-based and sky radiance measurements in Semi- Arid Climate and Environment Observatory of Lanzhou University （SACOL）, China. High aerosol optical thickness （AOT） associated with low .Angstrom exponent （α） was mainly observed in spring, which was consistent with the seasonal dust production from Hexi Corridor. The maximum monthly average value of AOT 0.56 occurred in March of 2007, which was two times larger than the minimum value of 0.28 in October of 2006. Approximately 60% of the AOT ranged between 0.3 and 0.5, and nearly 93% ofα value varied from 0.1 to 0.8, which occurred in spring. The significant correlation between aerosol properties and water vapor content was not observed. The aerosol volume size distribution can be characterized by the bimodal logarithm normal structure： fine mode （r 〈 0.6 μm） and coarse mode （r 〉 0.6 μm）. Aerosols in spring of SACOL were dominated by large particles with the volume concentration ratio of coarse to fine modes being 7.85. The average values of asymmetry factor （g） in the wavelength range 440-1020 nm were found to be 0.71, 0.67, 0.67 and 0.69 in spring, summer, autumn and winter, respectively.
基金This work was supported by the National Natural Science Foundation of China[grant number 41775154]the Six Talent Peaks Project in Jiangsu Province[grant number JNHB-057]the Postgraduate Practical Innovation Program of Jiangsu Province of China[grant number SJCX19_0301].
文摘A comprehensive agricultural inventory of ammonia emissions for 2017 in Hefei was established on the basis of the specific emission factors and county-level activity data.The emissions over a 1 km×1 km grid and the associated monthly variations were distributed on the basis of land-use type and meteorological conditions,respectively.The total ammonia emissions were 27,242.7 t in 2017 in Hefei,to which livestock was the top contributor,accounting for 54.5%.Two major contributors to livestock waste were broilers and laying hens,which contributed 34.5%and 22.2%of the total emissions,respectively.Changfeng,Feixi,and Feidong counties,with more developed agriculture than other counties,accounted for a large proportion of the total ammonia emissions—as much as 28.5%,24.5%,and 21.0%,respectively.The average emissions density of the whole region was 2.4 t km−2,and the higher values were mostly in areas with denser populations.Seasonally,peak ammonia emissions occurred in summer.
基金supported by the National Natural Science Foundation of China (No. 40533017, 20377008,40605001)the National Key Technology R&D Program(No. 2006BAC12B001)the State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (LAPC-KF-2006-05) of China
文摘The variations of sulfate formation and optical coefficients during SO2 heterogeneous reactions on hematite surface under different SO2 concentrations were examined using in situ diffuse reflectance infrared Fourier transform spectroscopy （DRIFTS） and ion chromatograph （IC）. Laboratory experiments revealed that within ambient SO2 of 0.51-18.6 ppmv, sulfate product, producing velocity, absorption and backward scattering coefficients showed an increasing trend with SO2 concentration. Under given SO2 concentration, the velocity of sulfate producing performed an evolution of initial increasing, midterm decreasing and final stabilizing. The reactive uptake and Brunaner-Emmett-Teller （BET） uptake coefficients of heterogeneous reactions rose with SOz and exhibited high reactivities. Considering global warming, this result is important for the knowledge of heterogeneous reactions of SO2 on mineral particle surface in the atmosphere and the assessment of their impacts on radiative forcing.
