Answer:
A Peltier junction is the same as a thermocouple junction, except instead of using heat to generate electric current an electric current is forced through it to move heat. Thus in a heatsink unit one junction (on the hot IC) gets cold removing heat and the other junction (on the heatsink fins) gets very hot. Thus it acts like a electric refrigeration system for the IC.
It has no moving parts (except maybe a fan) like the compressor and coolant in mechanical refrigerators. It is even reversible to make a heater by just reversing the electric current. Portable electric food cooler/heater units are available, these typically plug into a car cigarette lighter outlet.