题目
有一根1 , (m)长的柱子,柱效为3600。在一定条件下,两个组分的保留时间分别为12.2 , (min)和12.8 , (min),计算分离度。要达到完全分离,所需要的柱长。[W_1 = 4 (t_(r1))/(sqrt(n)) = (4 times 12.2)/(sqrt(3600)) = 0.8133][W_2 = 4 (t_(r2))/(sqrt(n)) = (4 times 12.8)/(sqrt(3600)) = 0.8533]分离度:[R = (2 times (12.8 - 12.2))/(0.8533 + 0.8133) = 0.72][L_2 = ( (R_2)/(R_1) )^2 times L_1 = ( (1.5)/(0.72) )^2 times 1 = 4.34 , (m)]
有一根$1 \, \text{m}$长的柱子,柱效为$3600$。在一定条件下,两个组分的保留时间分别为$12.2 \, \text{min}$和$12.8 \, \text{min}$,计算分离度。要达到完全分离,所需要的柱长。
$
W_1 = 4 \frac{t_{r1}}{\sqrt{n}} = \frac{4 \times 12.2}{\sqrt{3600}} = 0.8133
$
$
W_2 = 4 \frac{t_{r2}}{\sqrt{n}} = \frac{4 \times 12.8}{\sqrt{3600}} = 0.8533
$
分离度:
$
R = \frac{2 \times (12.8 - 12.2)}{0.8533 + 0.8133} = 0.72
$
$
L_2 = \left( \frac{R_2}{R_1} \right)^2 \times L_1 = \left( \frac{1.5}{0.72} \right)^2 \times 1 = 4.34 \, \text{m}
$
题目解答
答案
根据题意,$ W_1 = 4 \times \frac{12.2}{60} = 0.8133\,\text{min} $,$ W_2 = 4 \times \frac{12.8}{60} = 0.8533\,\text{min} $。
分离度为:
\[
R = \frac{2 \times (12.8 - 12.2)}{0.8133 + 0.8533} = \frac{1.2}{1.6666} = 0.72
\]
要达到 $ R = 1.5 $,需:
\[
\frac{R_2}{R_1} = \sqrt{\frac{L_2}{L_1}} \implies \frac{1.5}{0.72} = \sqrt{L_2} \implies L_2 = (2.0833)^2 = 4.34\,\text{m}
\]
最终结果:
分离度 $ R = 0.72 $,所需柱长 $ L = 4.34\,\text{m} $。