An underground storage tank (volume =1 m') spills its contents of 1 kg of TCE in a 10 m thick sand aquifer. the seepage velocity is 1 m/day in the x direction. the longitudinal dispersivity is Im, transverse and vertical dispersivities are 0.1 m. A) calculate the maximum concentration at distance x= 500m B) if the contaminant was uniformly spilled over the 10m thickness of the aquifer what is the m concentrations at x= 500m with longitudinal dispersivity is Im, transverse dispersivity is 0.1 m and vertical dispersivity=0

Consider steady 2D diffusion through a funnel. The funnel radius varies linearly with the distance along the funnel axis according to the following formula: rx=r0*(1+x/L). r0 = 1mm, L=1cm.

A diffusion couple of two metals, A and B, was fashioned as shown: Diffusion of A atoms A-B alloy B Diffusion of B atoms After a 690 hour heat treatment at 1120°C the concentration of A is 1.8 wt% at the 3.2 mm position within Metal B. At what temperature (in Kelvin) must the diffusion couple need to be heated to produce this same concentration at a 2.3 mm position after 690 h? The preexponential and activation energy values for the diffusion of A in B are 1.9 x 104 m²/s and 239 kJ/mol, respectively.

[Decarburization] An FCC iron-carbon alloy initially containing carbon with the concentration, C0, is exposed to anoxygen-rich and virtually carbon-free atmosphere. Under the given conditions, the carbon diffuses from the alloy andreacts at the surface with the oxygen in the atmosphere, meaning that the carbon concentration at the surface position is maintained essentially at 0 wt% C. The subproblems are independent.(1) Determine the diffusion coefficient at the temperature T given below.  Use T = 1250 °C(2) When the value of D is given below, what position will the carbon concentration be Cx after a treatment for thetime, t? Use D = 1.93 × 10−10m2 /s; C0 = 0.35 wt%; Cx = 0.11 wt%; t = 12 hr