کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
7609105 | 1493393 | 2018 | 15 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
On the relationship between radial structure heterogeneities and efficiency of chromatographic columns
ترجمه فارسی عنوان
در ارتباط بین ناهمگن ساختار شعاعی و کارایی ستون های کروماتوگرافی
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی آنالیزی یا شیمی تجزیه
چکیده انگلیسی
The theoretical calculations of the actual pre-asymptotic reduced van Deemter curves (2.1â¯mmâ¯Ãâ¯50â¯mm column, sub-2â¯Î¼m BEH-C18 FPPs, n-hexanophenone analyte, acetonitrile/water eluent, 80/20, v/v, flow rate from 0.05 to 0.35â¯mL/min) confirm that the impact of the sole THBL on column dispersion can be neglected. In contrast, the contribution of the TLOPL to the reduced plate height (RPH) is about 0.2â¯h unit at optimum reduced velocity. Most remarkably, the negative impact of the TLOPL on column performance may be fully compensated by the presence of the adjacent WDRPL if the depth of the velocity well were to be 5% of the bulk velocity. In actual 2.1â¯mmâ¯Ãâ¯50â¯mm columns packed with sub-2â¯Î¼m FPPs, this velocity depth is as large as 25% of the bulk velocity causing a significant RPH deviation of 0.7â¯h unit from the RPH of the bulk packing free from wall effects. Maximum column performance is expected for a reduction of WDRPL density. This suggests optimizing the packing process by finding the proper balance between the stress gradient across the WDRPL (responsible for the deep velocity well) and the friction forces between the packed particles (responsible for the rearrangement of the particles during bed consolidation). Past and recently reported RPH data support the theoretical insights: the stress gradient/particle friction balance in the WDRPL is better realized when packing superficially porous particles (SPPs) rather than FPPs in 2.1-4.6â¯mm i.d. columns (the RPH deviation is reduced to 0.4â¯h unit) or sub-2â¯Î¼m particles in 100â¯cmâ¯Ãâ¯75â¯Î¼m i.d. capillaries combining high slurry concentrations and sonication (the RPH deviation is reduced to only 0.15â¯h unit).
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Chromatography A - Volume 1533, 19 January 2018, Pages 112-126
Journal: Journal of Chromatography A - Volume 1533, 19 January 2018, Pages 112-126
نویسندگان
Fabrice Gritti,