| 摘要 |
907,921. Freezing blood, bone-marrow &c. UNION CARBIDE CORPORATION. Nov. 3, 1960 [Nov. 9, 1959], No. 37764/60. Drawings to Specification. Class 29. In freezing biological suspensions of cells, e.g. blood or bone-marrow, heat is abstracted from the walls of the suspension container at a rate of at least 14,000 B.T.U. per hour per square foot of container surface. The container, made of e.g. aluminium, magnesium or stainless steel and containing but not filled with the suspension, is immersed in liquid nitrogen or other liquefied gas at atmospheric pressure. To prevent a layer of heat-insulating nitrogen gas covering the surface of the container, the latter is coated with a heat insulating layer, e.g. of petroleum jelly, which reduces the temperature difference between the container surface and the refrigerant sufficiently. Generation of refrigerant bubbles may be enhanced by applying a powder to the surface of the insulating layer. Thawing is effected by water as quickly as possible and the heat insulating layer is preferably soluble in water. The container may be shaken during freezing and thawing. Specifications 777,232 and 777,233 are referred to. |
