**2. The establish of CLC method**

### **2.1 Column, support and heating apparatus**

The dimension of glass chromatographic column is 90 mm length and 6 mm I. D. Silica gel with particle size range from 100 to 200 meshes was provided by marine chemical plant of Qingdao China. Silica gel was active under temperature of 180oC for 4 hours before use. Oxide of alumna 0.047-0.147 mm used was purchased from chemical and medical reagent company in Shanghai China. Muffle furnace (50°C-1000°C) and oven was used for sample preparation and heating.

#### **2.2 Reagents**

N-heptane, dichloromethane, trichloromethane as eluent solvents all were analytical grade reagents produced by Tianjin Chemical Reagent Factory (China). Pure reagents as model compounds were supplied by Aldrich Chemical Company (USA), including tetracosane (99.5% pure), dibenz[ah]anthracen ( 98%, pure), and acetanilide ( 99% pure), etc.

#### **2.3 Analytical instruments**

Fourier transforms FT-IR spectra were measured by a Bio-Rad Excalibur Series FTS 3000 spectrometer in the range of 4000-400 cm−1 using KBr pellets. 1H NMR measurements were made with a Bruker Avance 500 spectrometer operating at 500.1 MHz.
