Study on steric transition in asymmetrical flow field-flow fractionation and application to characterization of high-energy material
Study on steric transition in asymmetrical flow field-flow fractionation and application to characterization of high-energy material
复制标题
DOI：
10.1016/j.chroma.2013.06.051
复制
发表时间：
2013-08-23
影响因子：
4.1
通讯作者：
Lee, Seungho
中科院分区：
文献类型：
--
作者：
Dou, Haiyang;Lee, Yong-Ju;Lee, Seungho
在场流分馏（FFF）中，存在“立体跃迁”现象，即样品洗脱模式从正常模式转变为立体/超层模式。FFF的准确分析需要理解立体转变现象，特别是当样品具有广泛的尺寸分布时，不同模式组合的效果可能变得复杂。本研究以聚苯乙烯（PS）乳胶珠为材料，研究了非对称流动FFF （AF4）中的立体跃迁现象。截留比(R)随着粒径的增大而逐渐减小（正常模式），在粒径0.5 μ m左右达到最小值（R-i），之后R随粒径的增大而增大（位阻/超层模式）。研究发现，随着通道厚度的增加，基于尺寸的选择性（S-d）有增加的趋势。研究了环-1,3,5-三亚甲基-2,4,6-三硝胺（通常称为“研究部炸药”（RDX））颗粒在AF4中的滞留行为。AF4在测定RDX颗粒尺寸时重复性好，相对标准偏差为4.1%。通过透射电镜（TEM）对AF4分离的可靠性进行了评价。(C) 2013 Elsevier B.V.版权所有
In field-flow fractionation (FFF), there is the 'steric transition' phenomenon where the sample elution mode changes from the normal to steric/hyperlayer mode. Accurate analysis by FFF requires understanding of the steric transition phenomenon, particularly when the sample has a broad size distribution, for which the effect by combination of different modes may become complicated to interpret. In this study, the steric transition phenomenon in asymmetrical flow FFF (AF4) was studied using polystyrene (PS) latex beads. The retention ratio (R) gradually decreases as the particle size increases (normal mode) and reaches a minimum (R-i) at diameter around 0.5 mu m, after which R increases with increasing diameter (steric/hyperlayer mode). It was found that the size-based selectivity (S-d) tends to increase as the channel thickness (w) increases. The retention behavior of cyclo-1,3,5-trimethylene-2,4,6-trinitramine (commonly called 'research department explosive' (RDX)) particles in AF4 was investigated by varying experimental parameters including wand flow rates. AF4 showed a good reproducibility in size determination of RDX particles with the relative standard deviation of 4.1%. The reliability of separation obtained by AF4 was evaluated by transmission electron microscopy (TEM). (C) 2013 Elsevier B.V. All rights reserved.