Where, exactly, are they showing the rectified sinewave?
The diagram at the top of the page has the caption of "non-sinusoidal", which it is! Possibly due to a phase-controlled unit/module/device.
The other instance, in the table, shows the output of a rectifier that has a significant forward voltage drop, i.e. no, zero output voltage for portions of the sinewave. I guess there is some artistic licence creeping into this diagram since you would not expect to see both positive and negative parts of the cycle as the output of any real-life rectifier circuit.