Fine-particle water and pH in the southeastern United States
نویسنده
چکیده
The copyright of individual parts of the supplement might differ from the CC-BY 3.0 licence. The nephelometer RH sensors were calibrated by placing the sensors in a sealed container above aqueous saturated salt solutions at known temperatures for an accurate prediction of equilibrium RH (Greenspan, 1977). More than 3hrs were allowed for each salt solution to reach water vapor saturation. Particle water was indirectly measured by two nephelometers. The difference between ambient and dry scattering coefficients (í µí¼ í µí± í µí±) is assumed to be caused by the loss of water. The ratio between ambient scattering coefficient and dry scattering coefficient is referred to as í µí±(í µí± í µí°»). í µí±(í µí± í µí°») = í µí¼ í µí± í µí± (í µí±í µí±í µí±í µí±í µí±í µí±í µí±¡) í µí¼ í µí± í µí± (í µí±í µí±í µí±¦) = ∫ í µí¼ 4 í µí± í µí± ,í µí±í µí±í µí±í µí±í µí±í µí±í µí±¡ í µí°· í µí±,í µí±í µí±í µí±í µí±í µí±í µí±í µí±¡ 2 í µí±(í µí°· í µí±)í µí±í µí°· í µí± ∫ í µí¼ 4 í µí± í µí± ,í µí±í µí±í µí±¦ í µí°· í µí±,í µí±í µí±í µí±¦ 2 í µí±(í µí°· í µí±)í µí±í µí°· í µí± (1) Page 2 of 9 where í µí± í µí± ,í µí±í µí±í µí±í µí±í µí±í µí±í µí±¡ and í µí± í µí± ,í µí±í µí±í µí±¦ are scattering efficiencies in ambient and dry conditions, respectively. í µí±(í µí°· í µí±) is the particle number distribution function. If í µí± í µí±¡ is the total number concentration, and í µí°· í µí± ̅̅̅̅ is the diameter of average surface, and í µí± í µí± ,í µí±í µí±í µí±í µí±í µí±í µí±í µí±¡ ̅̅̅̅̅̅̅̅̅̅̅̅̅ and í µí± í µí± ,í µí±í µí±í µí±¦ ̅̅̅̅̅̅̅̅ are average scattering efficiencies, then, í µí¼ í µí± í µí± (í µí±í µí±í µí±í µí±í µí±í µí±í µí±¡) í µí¼ í µí± í µí± (í µí±í µí±í µí±¦) = í µí¼ 4 í µí± í µí± ,í µí±í µí±í µí±í µí±í µí±í µí±í µí±¡ ̅̅̅̅̅̅̅̅̅̅̅̅̅ í µí°· í µí±,í µí±í µí±í µí±í µí±í µí±í µí±í µí±¡ ̅̅̅̅̅̅̅̅̅̅̅̅̅ 2 í µí± í µí±¡ í µí¼ 4 í µí± í µí± ,í µí±í µí±í µí±¦ ̅̅̅̅̅̅̅̅ í µí°· í µí±,í µí±í µí±í µí±¦ ̅̅̅̅̅̅̅̅ 2 í µí± í µí±¡ = í µí± í µí± ,í µí±í µí±í µí±í µí±í µí±í µí±í µí±¡ …
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