THE TEMPERATURE-COMPOSITION PHASE-DIAGRAM OF MONOMYRISTOLEIN IN WATER - EQUILIBRIUM AND METASTABILITY ASPECTS
THE TEMPERATURE-COMPOSITION PHASE-DIAGRAM OF MONOMYRISTOLEIN IN WATER - EQUILIBRIUM AND METASTABILITY ASPECTS
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DOI：
10.1016/s0006-3495(94)80847-1
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发表时间：
1994-03-01
影响因子：
3.4
通讯作者：
CAFFREY, M
中科院分区：
文献类型：
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作者：
BRIGGS, J;CAFFREY, M
用x射线衍射法绘制了单肉豆蔻醚在水中的温度-组成相图。从固定水合的样品中收集低角和广角衍射图案作为在X射线敏感膜和/或图像板上加热方向上的温度的函数。在该系统中确定的相包括层状结晶相，层状液晶相，流体各向同性相，和两个倒置的立方相。特别注意的是相平衡和相边界验证的问题。立方相过冷度检查通过调整温度的几个样品在立方相的层状液晶相代表平衡行为的值。冷却引起的结构和相变进行了连续监测超过30分钟的时间内，通过记录低角度的衍射图案，从样品使用条纹相机。随着样品水化程度的增加，微晶向层状转变的速率降低。此外，与0 ℃相比，在25 ℃的孵育温度下转变进行得更快。提出了一种机制，占非平衡条件下的相变的水化和温度敏感性。
The temperature-composition phase diagram of monomyristolein in water was constructed using x-ray diffraction. Low- and wide-angle diffraction patterns were collected from samples of fixed hydration as a function of temperature in the heating direction on x-ray-sensitive film and/or image plates. The phases identified in the system include the lamellar crystalline phase, the lamellar liquid crystalline phase, the fluid isotropic phase, and two inverted cubic phases. Particular attention has been devoted to the issues of phase equilibrium and phase boundary verification.Cubic phase undercooling was examined by adjusting the temperature of several samples in the cubic phase to a value where the lamellar liquid crystalline phase represents equilibrium behavior. Cooling-induced structure and phase changes were monitored continuously over a 30-min period by recording low-angle diffraction patterns from the samples using a streak camera. The cubic-to-lamellar transition rate decreased with increasing sample hydration. Additionally, the transition proceeded more rapidly at an incubation temperature of 25 degrees C compared to that at 0 degrees C. A mechanism is proposed that accounts for the hydration and temperature sensitivity of the phase transition under nonequilibrium conditions.