Which ones?(Yes, but how depends on what the are)L
Yes you can use all of these with DC, have you something specific in mind?
LEDS for example are DC only devices, loud speakers, buzzers and bleepers will work with pulsed DC.
What are you thinking of or are you asking us for ideas?
The peak voltage of a standard 120 volt AC line is 170 volts. That means that if something like a capacitor is rated to 120VAC, it will work for up to 170VDC applied through it. Conversely, if a capacitor is rated to 170VDC, it will only work for up tom 120VAC. Keep this ratio in mind.
No,don't have anything specific. I just wanted to know because when I salvage electronic components I know which ones I can use because I only use DC not AC