The concentrated extracts at four ripening stages were analyzed using capillary column gas chromatography (GC) for quantification of compounds. Capillary GC separation of volatile compounds was achieved by injecting 1 ll of each sample into a KONIK 4000A gas chromatograph operated with a DB-1 (Chrompack) capillary column (30 m 0.25 mm 0.25 lm). Helium was used as carrier gas at a flow rate of 1 ml/min. Injector Injector temperature was 250 C, detector temperature, 250 C and the oven temperature programme featured an initial temperature of 65 C (2 min hold), rising to 250 C at 4 C/min and held isothermal for 20 min. Quantitative data were calculated as area ratios of each compound/standard, from the areas measured electronically.
Identification of peaks was achieved by matching electron impact spectra (70 eV) to those of library spectra. The retention indices were determined using a series of n-paraffins (Maljat, Erdos, & Takacs, 1974). The identification of compounds was carried out by comparison of retention indices and mass spectra of standard compounds and also of mass spectra reported in the literature .
- UnlearnedLv 51 0 年前最佳解答
在四個成熟階段中的濃縮淬取，都使用毛細管氣相層析儀gas chromatography (GC)來進行化學物質的定量分析，將每種樣本1 ll (應是1ml?)注射到KONIK 4000A毛細管氣相層析儀中，以DB-1 (Chrompack) 毛細管 (30 m 0.25 mm 0.25 lm) 操作，它可以對揮發性化合物達成分離。以流速1 ml/min之氦氣為載體，注射器及檢測器溫度為25℃，而爐溫程式設定初溫為65℃ (維持2 分鐘), 以每分鐘4 ℃升溫至 250 ℃保持絕熱20 分鐘，以電子法量出面積，而計算得每種化合物的體積對標準值之比例的定量數據。
峰值的鑑定可由70 eV的電子衝擊光譜與館藏光譜相配來達成，而記憶力指數則利用n型石蠟系列 (Maljat, Erdos, & Takacs, 1974) 來測定，利用記憶力指數及標準化合物之質量光譜或本文獻所報告之質量光譜的對比，可以完成化合物的鑑定。
2007-05-11 13:33:47 補充：
對不起！疏於校對，淬取 應為 萃取。
- 汪汪Lv 41 0 年前
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