-273 Celsius is -459 F, which is absolute zero, molecular activity virtually stops (ZERO on the Kelvin scale).
297 K is 24 °C or 75 °F
However, liquid nitrogen temperature compared to -273 C is quite warm (77 K, -196 Celsius or ?? F)
I assume the parts in question would be dipped in nitrogen, as "absolute zero" can realistically be achieved only in laboratory conditions. Liquid hydrogen (4 K) is much much colder than nitrogen, all though still "warm" compared to absolute zero.
Liqiud Helium is the champ, 2 K
I worked on two of the Mauna Kea observatories on the island of Hawaii. Some of the scientists could do their observations using liquid nitrogen, others experiments had to use hydrogen. In the case of hydrogen they would use nitrogen as a "pre cooler". It was a long laborius process to get their instruments cooled down to liquid hydrogen temps.
Ernie
A better link for an explanation of the process is here:
http://pages.istar.ca/~cryo/theprocess.htm