For a $$typical$$ particle size distribution $($refer previous homework$),$ compute the

outdoor air PM$10$ and PM$2\mathrm{.}5$ concentrations in $\backslash$mu g m$3.$ Assume that the particle density is

uniform with size at $1\mathrm{.}0$ g cm$3.$

from previous home work answer that I got are

PM$10=62\mathrm{.}19\backslash$mu g$/$m$^3$

PM$2\mathrm{.}5=38\mathrm{.}796\backslash$mu g$/$m$^3$

$($b$)$ Consider a simple model of particles in indoor air. The indoor environment is

represented as a single well$-$mixed reactor. The only source of particles in this model

is outdoor air. Air flows through the building at a rate $\backslash$lambda v $=$ Q$/$V $[=]$ h$1,$ bringing

particles in from outside and also removing particles that are inside. Particles are also

lost from indoor air by deposition onto room surfaces, with a rate constant $\backslash$beta $[=]$ h$1.$

Given the parameters $\backslash$lambda v and $\backslash$beta $,$ derive an expression for the steady state ratio of

indoor to outdoor particle concentration, Ci$/$C$0.$

$($c$)$ For residential buildings, assume $\backslash$lambda v of $0\mathrm{.}5$ h$1.$ The deposition loss rate is a strong

function of particle size, and is reasonably represented by the following expressions: