function N=gausint(x);
% gausint is the function that contains a gaussian to be integrated. 
% No and DT are the surface concentration and the square of the 
% diffusion length, and are adjusted for 
% each new gaussian to be integrated.
No=1.0e20;
DT=0.16e-8;
%
N=No*exp(-x.^2/(4*DT));