cryocrystallography papers
The rates of cooling of small samples with cold N2 gas (100 K), liquid N2 (77 K) and liquid propane (100 K) have been measured. The samples were one bare Cu-constantan thermocouple and one coated with a 0.25 mm layer of silicone rubber cement. Gas cooling yielded the lowest rate, liquid N2 the highest. With the gas, cooling of the centers of the samples from 295 to 140 K took 0.8 and 2 s for the bare and coated samples, respectively; with liquid N2 the times were 0.15 and 0.6 s, and with liquid propane they were 0.15-0.18 and 1.2 s, respectively (time reproducibility is within ±10%).