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最近，中国科学院地球环境研究所牛振川研究员及合作者采用高时间分辨率的Δ14CO2观测，追踪了我国本底站冬夏季典型日变化中来自化石排放和生物排放的CO2对大气总CO2的贡献水平。并揭示了影响化石源CO2和生物源CO2变化的关键因素。研究表明：（1）尽管在本底地区，化石源CO2一日之内仍有较大的变化，可达几十个ppm。冬季化石源CO2普遍高于夏季，可观测到早晚交通引起的浓度小高峰。化石源CO2的日变化...
最近，中国科学院地球环境研究所周卫健院士带领的团队以西安市长期（2011–2016年）大气Δ14CO2观测为主，进而将观测扩展到全国15个主要城市，通过14C示踪准确定量了我国主要城市大气CO2ff的浓度水平，分析了其在不同城市之间的差异；并结合稳定碳同位素（13C）和WRF-Chem大气模式研究了盆地城市CO2ff的来源和传输。研究发现：(1)我国城市冬季1月份大气CO2ff浓度普遍高于夏季7月...
Sources and transport of Δ14C in CO2 within the Mexico City Basin and vicinity
Δ14C CO2 Mexico City Basin vicinity
2009/8/7
Radiocarbon samples taken over Mexico City and the surrounding region during the MILAGRO field campaign in March 2006 exhibited an unexpected distribution: (1) relatively few samples (23%) were below ...
Using 14C, 13C, 18O and 17O isotopic variations to provide insights into the high northern latitude surface CO inventory
14C 13C 18O and 17O isotopic variations high northern latitude CO
2009/3/12
Measurements of the complete isotopic composition of atmospheric CO (3CO, 14CO, C17O, C18O) have been carried out at the high northern latitude stations Spitsbergen, Norway, and Alert, Canada. The ann...
On the isolation of elemental carbon (EC) for micro-molar 14C accelerator mass spectrometry: development of a hybrid reference material for 14C-EC accuracy assurance, and a critical evaluation of the thermal optical kinetic (TOK) EC isolation procedure
elemental carbon EC TOK
2009/2/18
The primary objective of the research reported here has been the development of a hybrid reference material (RM) to serve as a test of accuracy for elemental carbon (EC) isotopic (14C) speciation meas...