The electronic structures of six mono-terpenoids and two of their oxygenated derivatives were studied by He I photoelectron spectroscopy(PES).The observed bands were interpreted on the basis of empirical arguments and theoretical calculations.The first vertical ionization potentials for β-pinene,α-terpinene,terpinolene,γ-terpinene,limonene,myrcene,citral,and terpinene-4-ol were determined to be 8.73,7.57,8.26,8.30,8.53,8.68,8.71,and 8.77 eV,respectively.Most of these values have not been determined by PES before.The correlations of the first vertical ionization potentials of these compounds to the natural logarithms of rate constants for their reactions with the radicals OH,NO3,and O3 were determined.The correlation coefficients for their reactions with OH,NO3,and O3 were 0.97,0.91,and 0.95,respectively.This method is a powerful technique for predicting the rate constants for the atmospheric oxidation reactions of terpenoids.
WANG XiaoPeng TONG ShengRui GE MaoFa WANG WeiGang WANG DianXun
<正>Aerosol observational data spanning three years(2005-2007) from the Chinese Sun Hazemeter Network(CSHN) wer...
Wupeng Du~a,Jinyuan Xin~a,Mingxing Wang~a,Qingxian Gao~b,Zhanqing Li~c,Yuesi Wang~(a,*) a Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029,PR China b Chinese Research Academy of Environment Science,Beijing 100012,PR China c Department of Meteorology,The University of Maryland,College Park,MD 20782,USA
<正>This paper describes an operational retrieval algorithm for the sand/dust storm(SDS) from FY-2C/SVISSR (Str...
X.Q.Hu~(1,3),N.M.Lu~1,T.Niu~2,and P.Zhang~1 1 Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites(KLRCV),National Satellite Meteorological Center,China Meteorological Administration(NSMC/CMA),Beijing 100081,China 2 Centre for Atmosphere Watch & Services(CAWAS),Chinese Academy of Meteorological Sciences,China Meteorological Administration(CMA),Beijing 100081,China 3 Institute of remote sensing applications,Chinese Academy of Sciences,Beijing 100101,China
Asian dust storm (ADS) samples were collected on March 20,2002 in Beijing,China. High-resolution field emission scanning electron microscopy with energy dispersive X-ray detector (FESEM-EDX) and X-ray diffraction (XRD) were used to study the morphology,chemical compositions,number-size dis-tributions and mineralogical compositions of ADS particles. The mineral particles were major compo-nents in the ADS samples,accounting for 94% by number. The XRD analysis indicated that the dust particles were dominated by clay (40.3%),and quartz (19.5%),followed by plagioclase (8.4%),calcite (7.5%),K-feldspar (1.5%),hematite (0.9%),pyrite (0.9%),hornblende (0.4%) and gypsum (0.3%),with a certain amount of noncrystalline materials (20.3%). Clay minerals were mainly illite/smectite mixed lay-ers (78%),followed by illite (9%),kaolinite (6%),and chlorite (7%). In addition to these main minerals,FESEM-EDX also detected some trace minerals,such as dolomite,pyrite,thenardite,as well as heavy minerals represented by rutile,ilmenite and apatite. The mineralogical compositions of the 2002-03-20 Asian dust storm and the Saharan dust plumes were similar but the clay mineralogy showed a great distinction,with the illite/smectite mixed layers being common in the Asian dust storm but illite being common in the Saharan dust plumes.
Recent field and experimental studies have suggested that acid-base reactions of alkylamines may play an important role in secondary aerosol formation. We investigated the heterogeneous chemistry of ethylamine (EA), diethylamine (DEA) and triethylamine (TEA) on liquid H2SO4 (1 wt%–80 wt%). Irreversible reactive uptakes were observed for all three alkylamines. The reactive uptake coefficients (γ ) of alkylamines increased with the acid concentration, and the γ value for DEA appeared to increase slightly faster than that of EA and TEA. The potential roles in secondary aerosol formation of different alkylamines are briefly discussed.
