The unit of -axis in Figure 14 is not kJ/min actually, so the number of labels of -axis is not correct. Here we modify the figure by using kJ/min as the unit, as shown in what follows. The curvilinear trends of the curves are not changed. Discussions of the result in the paper are not affected by the correction.

We also take this opportunity to correct two expression errors which may cause confusion to the readers. The line “The heat energy loss from water…” above (1) should be corrected as “The heat energy gained by water…”. The line “The heat energy income for the concrete…” above (2) should be corrected as “The heat energy loss from the concrete…”.


We are very grateful to Liu Guowei for pointing out the errors.