ii The AUC mainly show a flat trend when temperature changing Bobaly et al 2016

Ii the auc mainly show a flat trend when temperature

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ii. The AUC mainly show a flat trend when temperature changing ( Bobaly et al 2016 ). All these figures are suitable with the hypothesis. iii. W decreases as the temperature increases. The width keeps decreasing from 0.247 in 25 degree to 0.19 in 60 degree. iv. The reduce rate keep steady. All these figures are suitable with the hypothesis. v. Height on the other hand will increases. The height increases from 626 (25 degree)to 771 (40 degree) when temperature increases, and almost keep in a the same figure from 40 degree to 60 degree vi. All these figures are suitable with the hypothesis. We also expected that the backward pressure will decrease as the temperature increases. vii. The graph shows that the back pressure dramatically decreases (from 149 bar to 83 bar) along with the growth of temperature degree (from 25 to 60). And the reduce rate keep steady. The result is suitable for our hypothesis. We assumed that
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HPLC CHROMATOGRAPHY 12 the retention time should decreases along with the growth of temperature. The graph shows that the retention time dramatically decreases (from 3.12 min to 1.95 bar) along with the growth of temperature degree (from 25 to 60). The result is suitable for our hypothesis. Chromatographic Analysis results and the trend graphs. Graphical representation X - Temperature Y- AUC In the graph, the X axes is the temperature, the Y axes are AUC. The curve of AUC can be seen as flat, although the temperature changes. For ideal condition (completely separate), the AUC is only influenced by the amount of injection sample. During the practical, we didn't change the injection volume. Therefore, the AUC will maintain in a flat figure as the result shows. In the graph, the X axes is the temperature, the Y axes is Width. The curve of W shows a visible decrease trend with the increase of temp. Because the temperature increase, the molecule have higher energy and move faster, which reduce the time both in the mobile phase and stationary phase with higher flow rate. Hence, the Tr and t0 will decrease following the increasing of efficiency. As it shows on the graph, width is influnced to show a decrease trend by the temperature increase. In the graph, the X axes is the temperature, the Y axes is height. The H shows a visible increase trend with the increase of temp. H is dependent variable of W and AUC. As
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HPLC CHROMATOGRAPHY 13 mentioned above, AUC stays in same and W decrease with the temp increase. Therefore, H will increase by the temp increase. In the graph, the X axes is the temperature, the Y axes is back pressure (unit: bar). We can clearly find that the back pressure shows an obviously decreased trend by the temperature increase. That means that the higher temperature the column is, the less back pressure in the HPLC test. Temperature can affect retention and selectivity of a separation. An increase in temperature will reduce retention times; this will allow the ability to work at higher flow rates. The ability to work at higher flow rates is attributable to a reduction in viscosity of the mobile phase as the temperature is increased. This reduces back pressure.
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