Study of the solid-liquid state diagram of the water-glycine-sucrose system
Study of the solid-liquid state diagram of the water-glycine-sucrose system
复制标题
水-甘氨酸-蔗糖体系固-液状态图的研究
DOI：
10.1006/cryo.1994.1045
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发表时间：
1994
期刊：
影响因子：
2.7
通讯作者：
A. Kanev
中科院分区：
文献类型：
--
作者：
E. Shalaev;A. Kanev
摘要采用差热分析和X射线衍射研究了不同冷却和加热速率下的水-甘氨酸-蔗糖体系。在冷冻和冻干样品的加热过程中，观察到的最显著的转变是：玻璃化转变。T G，这是由热容突变引起的；机械玻璃化转变（“防熔”）T AM (T AM > T G)，这与非晶相中粘流的出现有关，这是由其自重引起的；脱硝作用，在富水样品中是冰+ β-甘氨酸的二次结晶，在低水样品中是蔗糖+甘氨酸的二次结晶。用描述玻璃化转变、机械玻璃化转变和反玻璃化的线和面数据的多项式近似来描述固液状态图。利用这些数据来描述冻干途径。
Abstract The water-glycine-sucrose system was studied by DTA and X ray diffraction at various cooling and heating rates. The following transitions were the most distinctive of those observed during heating of the frozen and freeze-dried samples: the glass-transition. T G , which is due to an abrupt change of heat capacity; the mechanical glass-transition ("ante-melting") T AM ( T AM > T G ), which is related to the appearance of viscous-flow in the amorphous phase, caused by its own weight; devitrilication, which is the secondary crystallization of ice + β-glycine in water-rich samples, and sucrose + glycine crystallization in low-moisture samples. The solid-liquid state diagram has been described by polynomial approximations to the data describing the lines and surfaces of the glass-transition, the mechanical glass-transition, and devitrification. Use of these data to describe the freeze-drying pathway is presented.