【作者】 苏同福；

【导师】 宫长荣；

【作者基本信息】 河南农业大学 ， 烟草学， 2008， 博士

【摘要】 本研究采用高沸醇溶剂的方法,用90 %左右的1,4-丁二醇溶液,对烟梗体内的木质素进行提取。在所选取因素水平内,利用正交设计,寻求分离提取烟梗木质素最佳条件。研究结果显示,选用浓度90 %的1,4-丁二醇溶液、使用催化剂C、温度为220℃及时间为120 min的条件下,木质素的产量最高。同时,也找到了另一个有效的催化剂A。由于催化剂C和催化剂A的催化剂能力相差不大,但因催化剂C的价格较高,因此,在实际的生产中推荐使用催化剂A。本研究首次采用激发波长785 nm的激光器,检测出了木质素的拉曼光谱,其检测条件为:功率0.5 mW,将散射光聚焦到样品上直径约1μm区域内,数据采集时间为100 s,测定范围3000 ~100 cm-1。检测功率不能超过4 mW,否则木质素就会被烧焦。同时也对其谱线做了归属,特别是在拉曼位移2048 cm-1中等强度的峰,该峰是一个异常的峰,本研究初步归属为低波数区域的组频和/或倍频。本研究首次采用太赫兹光谱系统,测定了木质素在0.3~2.0 THz频率区域太赫兹图谱,结果表明:木质素折射率曲线可以拟合成一条斜率为负的直线,但其吸收系数的曲线,可以拟合为一条斜率为正的直线,而且,不同分子量的木质素的斜率相差较大。本研究首次采用太赫兹光谱系统,测定不同方式处理的烟梗在0.3~1.5 THz之间的太赫兹图谱,结果显示:醇烟梗的折射率图谱在该频率区域,可以拟合成一条斜率为负的直线,其拟合方程为:Y =1.84857-5.23397E-14 X,但原烟梗、水烟梗以及膨胀烟梗却可以拟合成一条多项式方程,原因可能是醇烟梗中的木质素被提取出来后,致使醇烟梗的木质素含量很少,而其它三种烟梗中的木质素含量较高。同时,四种烟梗样品吸收系数,基本上都可以拟合成斜率为正的直线,但斜率相差较大。太赫兹实现技术在烟草化学中的应用,拓宽了一条研究烟草及卷烟制品的新方法、新途径。更多还原

【Abstract】 In this work, lignin in the midribs of tobacco leaves was extracted through high boiling solvent-1,4-butylene-glycol (90 % or so). The optimum condition of extraction lignin from midribs of tobacco leaves was found through orthogonal design. The result shows that: the yield of lignin was the highest under the condition of 90 % 1,4-butylene-glycol solution, temperature of 220℃, time of 120 minutes and catalyst C. Another effective catalyst A was also found. Catalyst A was recommended to be used during production practice due to its lower cost.Raman spectrum of lignin from midribs from tobacco leaves was detected by using 785 nm laser for the first time. The Raman intensities of HBS-lignin was measured through a high resolution Raman systems (JY-HR-800) with confocal microscopy. A 100 X microscopy objection lens was used for focusing the laser beam and the collection of the scattered light. The spot diameter of the focused laser beam on the sample is about 1μm. A solid-state diode laser was used as an excited source 785 nm. The laser power on the sample was kept at 0.5 mw and typical spectrum acquisition time was 100 s. If the source power is over 4 mW, lignin would be burned. The bands in Raman spectrum were assigned; the especial 2048 cm-1 band was assigned to overtones and/or combinations.Terahertz spectra of lignin from midribs of tobacco leaves were measured through terahertz-TDS at frequency of 0.3~2.0 THz. The results show that: the data of refractive index of lignin can be fit using a line with negative slope, while the data of absorption coefficient about lignin can fit using a line with positive slope. Furthermore, the difference on the slope values of absorption coefficient is caused by the difference of lignin’s molecular weight.Terahertz spectra of midribs from different chemical treatments were also measured through terahertz-TDS at terahertz range of 0.3~1.5 THz. The results show that: the data of refractive index about alcohol midribs can be fit by a line with negative slope, which is Y =1.84857-5.23397E-14 X, at this frequency range but the data of the other 3 samples i.e. original, expanded and water midribs can be fit by polynomial equations; at the same time, the data of absorption coefficients from the 4 samples of midribs can all be fit by lines with different slopes.A new method to detect tobacco leaves and cigarette products was developed using terahertz techniques.更多还原