Dorset D L
Electron Diffraction Department, Hauptman-Woodward Medical Research Institute, Inc., Buffalo, NY 14203-1196, USA.
Acta Crystallogr B. 1995 Dec 1;51 ( Pt 6):1021-8. doi: 10.1107/s0108768195005465.
Quantitative electron crystallographic studies have been carried out on epitaxially oriented multi-component waxes. Intensities from two paraffin-based samples, an artificial six-component medium wax (equimolar distribution of chain lengths) and a petroleum-based wax (Gaussian distribution of chain lengths) have been used to determine their crystal structures. As found earlier for binary paraffin solid solutions, differences in molecular volume are compensated by longitudinal molecular shifts within individual lamellae. Nevertheless, each lamellar surface must remain flat enough, and with enough crystallographic order intact, to nucleate the next lamella, thus accounting for the observed long-range correlation in these crystals. Recrystallized beeswax also has a layer packing somewhat similar to the paraffin waxes. However, in this case, the lamellar order is 'frustrated' so that a certain amount of 'nematically' ordered material must be present, spanning the nascent lamellar interfaces.
已对外延取向的多组分蜡进行了定量电子晶体学研究。来自两个石蜡基样品的强度，即一种人工六组分中蜡（链长等摩尔分布）和一种石油基蜡（链长高斯分布），已被用于确定它们的晶体结构。正如早期在二元石蜡固溶体中所发现的那样，分子体积的差异通过单个片层内的纵向分子位移得到补偿。然而，每个片层表面必须保持足够平坦，并且有足够完整的晶体学有序性，以便为下一个片层成核，从而解释了在这些晶体中观察到的长程相关性。重结晶蜂蜡也具有与石蜡有些相似的层状堆积。然而，在这种情况下，片层有序性受到“阻碍”，以至于必须存在一定量的“向列型”有序材料，跨越新生的片层界面。
