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\input{00_myPreamble.tex}
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\begin{document}
\begin{align*}
\text{thermal equilibrium:} \quad \Delta T &= (T' - T'') = 0\\
\text{mechanical equilibrium:}\quad \Delta p &= (p' - p'') = 0\\
\text{diffusional equilibrium:} \quad \Delta \varphi_i &= (\varphi_i' - \varphi_i'') = 0
\end{align*}
\end{document}