查看文章

The natural radionuclides ²¹⁰Pb and ⁷Be have been widely used as tracers of aerosols for the study of pollution and atmospheric transport processes. The depositional fluxes of atmospheric ²¹⁰Pb and ⁷Be-bearing aerosols in precipitation samples have been continuously measured from October 2006 to April 2010 at a high altitude city of Murree (33° 85′ N, 73° 41′ E, Alt.2300m a.s.l) and low altitude city of Islamabad (33° 38′ N, 73° 09′ E, Alt. 534m a.s.l), Pakistan, using a high resolution spectrometer. The specific activity values of ²¹⁰Pb and ⁷Be measured in rain samples collected monthly from open lawn of Murree ranged from 2–87 mBq l⁻¹ and 80–1680mBql⁻¹ with their mean values of 30±11mBql⁻¹ and 573±201mBql⁻¹, respectively. Similarly the mean specific concentration values of ²¹⁰Pb and ⁷Be in open lawn rain samples of Islamabad are 123±12mBql⁻¹ and 442±321mBql⁻¹ respectively. The …