測試 l/2 l/4 wave plate

https://www.youtube.com/watch?v=_sUVXHfUVsY https://www.youtube.com/watch?v=EBVNbRN805o

Nautilus: file tree sidebar missing

I've installed the latest Scientific Linux 6. But when I opened the included Nautilus file manager, there is no file tree sidebar and no toolbar, nor status bar. How do I activate them? >>>> For the sidepane, you can either hit F9 or go to View and select sidepane. Similarly, for the toolbar and status bars, select them from the View menu.