1.Therefore, even the ratioof the abundanceratioof the two essential standards reaches 5,the relative derivation of results determined by the two methods as mentioned above is much less than 0.01 %.
3.After leaching with diluted nitric acid,21 aerosol samples collected on glassfiber filter in Tianjin from November 1998 to February 1999 were analyzed for ?ρ?(Pb),?w?(Pb) and isotopic abundanceratioof ????206?Pb/????207?Pb.
6.In most of the inclusions studied, researchers determined that the abundanceof 26Al at the time of their formation—expressed as a ratioof 26Al to the more common 27Al—was about 4.5×10-5.
9.The determination and confirmation were made by means of selected monitoring ions(SM) mode,SIM(m/z) were 231,233,288 amu( abundanceratio was 100:14:11),using external standard method.
10.The 48 h air mass back trajectory map provided plenty of detailed meteorological information and ,combined with ?ρ?(TSP),?ρ?(Pb) and ?w?(Pb) as well as lead isotopic abundanceratio,can be used to characterize lead pollution in air. ?
