Heat conduction is described by Fourier's law
\(\dot{Q}=\kappa \frac{dT}{dx}\)
We assumes to heat baths at temperature T1 and T2, connected by a heat conductor with cross section area A and separated by the length L.
The heat conducted from the hotter to the colder bath is given by
\(P=\frac{A}{L}\left(\Theta_1-\Theta_2\right)\)
where \(\Theta\) is a material property given by the integral of the heat conductivity coefficient \(\kappa\)
\(\Theta_1(T_1)=\int_0^{T_1}\kappa(T)\,dT\)