Match the following air pollutants with the most appropriate adverse health effects :
| Air pollutant | Health effect to human and/or test animal |
|---|---|
| (P) Aromatic hydrocarbons | (IV) Carcinogenic effect |
| (Q) Carbon monoxide | (I) Reduce the capability of the blood to carry oxygen |
| (R) Sulfur oxides | (II) Bronchitis and pulmonary emphysema |
| (S) Ozone | (III) Damage of chromosomes |
A sample of air analyzed at 25$$^\circ$$C and 1 atm pressure is reported to contain 0.04 ppm of SO2. Atomic mass of S = 32. O = 16. The equivalent SO2 concentration (in $$\mu$$g/m2) will be __________. (round off to the nearest integer)
The concentration s(x, t) of pollutants, in a one-dimensional reservoir at position x and time t satisfies the diffusion equation
$${{\partial s(x,t)} \over {\partial t}} = D{{{\partial ^2}s(x,t)} \over {\partial {x^2}}}$$
on the domain 0 $$\le$$ x $$\le$$ L, where D is the diffusion coefficient of the pollutants. The initial condition s(x, 0) is defined by the step-function shown in the figure.
The boundary conditions of the problem are given by $${{\partial s(x,t)} \over {\partial x}}$$ = 0 at the boundary points x = 0 and x = L at all times. Consider D = 0.1 m2/s, s0 = 5 $$\mu$$mol/m and L = 10 m. The steady-state concentration $$\overline s \left( {{L \over 2}} \right) = s\left( {{L \over 2},\infty } \right)$$ at the center x = $${{L \over 2}}$$ of the reservoir (in $$\mu$$mol/m) is __________. (in integer)