PRINT; -reset false SOLUTION 0 pH 6 charge; N(5) 1e-3; Na 0.1; Cl 0.1 -water 1e5 # increase the volume for constant concentrations, because # concentration changes are calculated when electro-migration is invoked SOLUTION 1-30 pH 4 charge; N(5) 0.1; Na 0.1; Cl 0.1 -water 0.3333 SOLUTION 31 pH 4 charge; N(5) 0.1; Na 0.1; Cl 0.1 -water 1e5 END TRANSPORT -cells 30 -lengths 3.333e-4 -boundary_conditions 1 1 -punch_cells 0-31 -shifts 10 -fix_current -1e-10 -flow_direction diffusion_only -time 2 min 1 -multi_d true 1e-9 1 0.0 1.0 -implicit true 4 USER_GRAPH 1 implicit Nernst-Planck solution : concentrations -headings dist H+ NO3- Na+ Cl- -initial_solutions false -axis_scale y_axis 0.0 0.12 -axis_scale x_axis 0 10 -axis_titles "Distance / mm" mmol/kgw -plot_concentration_vs x 1 if total_time <> 1200 then end 10 graph_x dist * 1e3 20 graph_y mol("H+")*1e3, mol("NO3-")*1e3, mol("Na+")*1e3, mol("Cl-")*1e3 USER_GRAPH 2 implicit Nernst-Planck solution : potential -init false -axis_scale x_axis 0 10 -axis_titles "Distance / mm" "potential / mV" -plot_concentration_vs x 1 if total_time <> 1200 then end 10 graph_x dist * 1e3 20 graph_y pot_V * 1e3 USER_GRAPH 3 Nernst-Planck solution : current -axis_scale x_axis 0 20 -axis_titles "Time / min" "current / A" -plot_concentration_vs t 1 if cell_no <> 1 then end 10 graph_x total_time / 60 20 graph_y current_A END USER_GRAPH 1; -active false USER_GRAPH 2; -active false USER_GRAPH 3; -active false SOLUTION 0 pH 6 charge; N(5) 1e-3; Na 0.1; Cl 0.1 SOLUTION 1-31 pH 4 charge; N(5) 0.1; Na 0.1; Cl 0.1 -water 0.3333 TRANSPORT -boundary_conditions 1 2 -shifts 1; -time 20 min -fix_current 0 USER_GRAPH 4 Zero charge transport -headings dist H+ NO3- Na+ Cl- -axis_scale y_axis 0.0 0.12 -axis_scale x_axis 0.0 10 -axis_titles "Distance / mm" mmol/kgw -plot_concentration_vs x -initial_solutions true -start 10 if step_no > 0 then goto 60 20 if cell_no > 1 then goto 80 # concentrations at the boundary (x = 0, solution 0)... 30 graph_x 0 40 graph_y 0.001, 0.001, 0.1, 0.1 50 goto 80 60 graph_x dist * 1e3 70 graph_y mol("H+")*1e3, mol("NO3-")*1e3, mol("Na+")*1e3, mol("Cl-")*1e3 80 end -end END