Observed trends for CF3-containing compounds in background air at Cape Meares, Oregon, Point Barrow, Alaska, and Palmer Station, Antarctica.
Observed trends for CF3-containing compounds in background air at Cape Meares, Oregon, Point Barrow, Alaska, and Palmer Station, Antarctica.
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DOI：
10.1016/j.chemosphere.2003.11.002
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发表时间：
2004-05
期刊：
影响因子：
8.8
通讯作者：
J. A. Culbertson;J. Prins;E. P. Grimsrud;R. A. Rasmussen;M. Khalil;M. J. Shearer
中科院分区：
文献类型：
--
作者：
J. A. Culbertson;J. Prins;E. P. Grimsrud;R. A. Rasmussen;M. Khalil;M. J. Shearer
采用高分辨率气相色谱法和高分辨率质谱法测定了1978年至1997年在俄勒冈州的米尔斯角、1995年至1998年在阿拉斯加的巴罗角和1991年至1997年在南极洲的帕尔默站采集的存档空气样品中含CF 3化合物的浓度。用这种方法测量的含CF 3的化合物有：全氟化合物C3 F8（FC 218）;四种全卤代化合物CF 3Cl（CFC 13）、CF 3CF 2Cl（CFC 115）、CF 3CFCl 2（CFC 114 a）和CF 3Br（Halon 1301）;三种氢氟化合物CF 3 H（HFC 23）、CF 3CH 3（HFC 143 a）和CF 3CH 2F（HFC 134 a）。对于这些化合物中的四种，以前报道的测量很少。所有含CF 3化合物的大气浓度在样品收集期间随时间不断增加。根据这些数据，估算了向大气中排放的年速率。排放率分为三个不同的类别之一。C3 F8、CF 3 H、CF 3CH 3和CF 3CH 2F的年排放率在过去20年中持续增加。CF_3CFCl_2的电导率不断下降。CF 3Cl、CF 3CF 2Cl和CF 3Br的排放率在20世纪80年代后期达到最高水平，并在20世纪90年代一直在下降。20年前，C3 F8、CF 3CH 3和CF 3CH 2F的排放率几乎为零，但在过去十年中迅速增加。
The concentrations of CF3-containing compounds in archived air samples collected at Cape Meares, Oregon, from 1978 to 1997, at Point Barrow, Alaska, from 1995 to 1998, and at Palmer Station, Antarctica, from 1991 to 1997, were determined by high resolution gas chromatography and high resolution mass spectrometry. The CF3-containing compounds measured by this method and discussed here are: the perfluorinated compound, C3F8(FC 218); four perhalogenated compounds, CF3Cl (CFC 13), CF3CF2Cl (CFC 115), CF3CFCl2(CFC 114a), and CF3Br (Halon 1301); and three hydrofluorocompounds, CF3H (HFC 23), CF3CH3(HFC 143a), and CF3CH2F (HFC 134a). For four of these compounds, very few measurements have been previously reported. The atmospheric concentrations of all of the CF3-containing compounds continuously increased in time over the sample collection periods. From these data, the annual rates of emission into the atmosphere have been estimated. The emission rates fall into one of three distinct categories. The annual emission rates of C3F8, CF3H, CF3CH3, and CF3CH2F have continuously increased over the last two decades. That of CF3CFCl2has decreased continuously. Emission rates for CF3Cl, CF3CF2Cl, and CF3Br reached maximum levels in the late 1980s, and have been decreasing in the 1990s. The emission rates of C3F8, CF3CH3and CF3CH2F were nearly zero 20 years ago but have increased rapidly during the last decade.