Resolution greatest effect

One of the simplest ways to improve resolution is to adjust the capacity factor for solute B. If all other terms in equation 12.21 remain constant, increasing k improves resolution. As shown in Figure 12.11, however, the effect is greatest when the... 

A review of 18 controlled studies in otherwise typically developing children (Moffatt et ah, 1993) demonstrated that only about 24% of children were completely dry while on medication and that 94% relapsed after medication was discontinued. In the Swedish Enuresis Trial (SWEET), 399 children aged 6-12 years with primary enuresis participated in an open, multicenter trial of DDAVP (Tullus et ah, 1999). Subjects were observed for 4 weeks and had their DDAVP dose titrated over 6 weeks (20 0 pg), followed by a 1-year long-term treatment period. A total of 245 children (61%) experienced a 50% or more reduction in the number of wet nights, with resolution of enuresis in 77 children. The greatest therapeutic effect was observed in children 6-7 years of age. There were no studies on the effectiveness of DDAVP in children with MR. 

Furthermore, the effect of sample volume on peak width will be greatest for the early peaks (the most narrow peaks) and will progressively decrease for all subsequent peaks. As the resolution of both late and early peaks must be given equal priority, the sample volume must be chosen such that the increase in the width of the first unretained peak is restricted to 5%. 

Temperature and pressure are rarely optimized in HPLC, but these parameters are very important in SFC, hence can alter retention, selectivity, and resolution. Toribio et al. [149] presented the chiral separation of ketoconazole and its precursors on Chiralpak AD and Chiralcel OD CSPs. The authors also reported that alcohol modifiers provided better separation than acetonitrile. Further, Wilson [143] studied the effects of composition, pressure, temperature, and flow rate of the mobile phase on the chiral resolution of ibuprofen on a Chiralpak AD CSP. It was observed that temperature affords the greatest change in resolution, followed by pressure and composition. An increase in methanol concentration, pressure, and temperature has resulted in poor chiral resolution. At first chiral resolution increased with an increase of flow rate (up to 1.5 mL/min) but then started to decrease. Contrary to this, Biermann et al. [135] described the... 

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