作者: M. Victoria Santos , M. Sansinena , J. Chirife , N. Zaritzky
DOI: 10.1016/J.CRYOBIOL.2014.10.010
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摘要: Abstract The knowledge of the thermodynamic process during cooling reproductive biological systems is important to assess and optimize cryopreservation procedures. time–temperature curve a sample immersed in liquid nitrogen enables calculation rates helps determine whether it vitrified or undergoes phase change transition. When dealing with cryogenic liquids, temperature difference between solid high enough cause boiling liquid, can undergo different regimes such as film and/or nucleate pool boiling. In present work, surface heat transfer coefficients (h) for plastic French straws plunged were determined using measurement curves. filled ice used showed an abrupt slope which was attributed transition into regime. h value that fitted each stage calculated numerical finite element program solves partial differential equation under transient conditions. corresponding regime, best experimental results h = 148.12 ± 5.4 W/m2 K nucleate-boiling h = 1355 ± 51 W/m2 K. These values further validated by predicting fluid system (bovine semen-extender) freezing. Good agreement obtained predicted profiles, confirming accuracy previously ice-filled straw. corroborated literature correlations. determination govern when plunging constitutes issue trying Furthermore, this information lead improvements design devices cryobiology field.