ICE FORMATION IN AQUEOUS MEDIA OF BIOLOGICAL INTEREST

Abstract

A bibliography is presented of research which emphasized the importance of the cooling rates in the preservation of biological material in the frozen state (such as would be the case, for example, in the preservation of blood). The cooling rates obtained by immersion of specimens in various refrigerants, including liquid nitrogen under pressure or at its freezing point, and liquid helium II, were measured. The method of increasing the rate of cooling of an object immersed in a boiling refrigerant by coating the object with a vapor-nucleating substance was investigated; in some cases the rate could be increased 23 times. The study of the structural instability and molecular mobility in rapidly cooled aqueous solutions which are partly crystalline and partly amorphous furnished information on changes occurring at the temperatures of (a) the 'glass transition', (b) devitrification, (c) recrystallization (of which 4 kinds were distinguished), and (d) eutectic melting. These changes were investigated by various methods, in particular, dilatometry, calorimetry and X- ray diffraction. Tentative applications of our basic studies to biological materials included determinations of the waterbinding capacity of the tissues of hibernating animals.

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Document Details

Document Type
Technical Report
Publication Date
May 01, 1967
Accession Number
AD0651765

Entities

People

  • Alan P. Mackenzie
  • B. J. Luyet
  • Calvin Kroener
  • Gabriel L. Rapatz
  • J. Tanner

Tags

DTIC Thesaurus Topics

  • Aqueous Solutions
  • Blood Coagulation
  • Cooling
  • Cryobiology
  • Freezing
  • Glass
  • Glass Transition Temperature
  • Instability
  • Liquids
  • Low Temperature
  • Materials
  • Nitrogen
  • Recrystallization
  • Transition Temperature
  • Transitions
  • Water
  • X Rays

Readers

  • Analytical Chemistry
  • Polymer Science and Engineering.
  • Theoretical Analysis.