  The paper studies the large-time behavior of solutions to the Robin problem
for PDEs with critical nonlinearities. For the considered problems,
nonexistence results are obtained, which complements the interesting recent
results by Ikeda et al. [J. Differential Equations, 269 (2020), no. 1,
563-594], where critical cases were left open. Moreover, our results provide
partially answers to some other open questions previously posed by Zhang [Proc.
Roy. Soc. Edinburgh Sect. A, 131 (2001), no. 2, 451-475] and Jleli-Samet
[Nonlinear Anal., 178 (2019), 348-365].
