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181.
再造烟叶如今已成为现代卷烟配方设计的一种重要原材料,但是造纸法再造烟叶生产中会产生大量高色度的废水,如何经济快速合理地处理再造烟叶的生产废水,解决再造烟叶生产带来的环境污染问题,已成为一个亟须解决的社会问题。以再造烟叶生产废水为主要研究对象,从不同来源的污泥样品中筛选出56株菌株,从生理生化性质方面对其中降解能力较强的10株进行初步鉴定。同时,研究了复合菌群对废水的综合脱色效果,发现在温度37℃、pH 6.0、接种量20%的条件下脱色效果最好,在最优条件下进行混合菌群脱色,14 h脱色率可达76.6%。 相似文献
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Xiaoyu Wang Shaofeng Liu Qiaoling Xia Ge Zhao Jizhao Guo Fuwei Xie 《Journal of separation science》2013,36(23):3750-3757
Tobacco is a complex chemical matrix. The analysis of trace alkaline flavors in tobacco is very difficult because of the limited peak capacity of monodimensional GC. In the present study, a home‐assembled twin‐oven GC–GC–MS system, with MS detection in both dimensions, has been applied to the analysis of 20 alkaline volatiles in a variety of cut‐tobacco samples. By transferring nine and six heart‐cuts from the first apolar column to the second polar column in two separate runs, the potential mutual interference of adjacent isomeric targets and the complex matrix could be removed. For comparative purposes, a systematic comparison of both quantification and qualification results for the cut‐tobacco sample as quality control was conducted between GC–GC–MS and GC–MS. The results showed that GC–GC–MS provided higher accuracy in peak assignment and quantification. And in GC–MS, the interferences of co‐elution had caused both low matched similarity in peak assignment and false‐negative/‐positive results in quantification for some targets. Advantages of the developed GC–GC–MS method in the analysis of alkaline flavors are its high resolving power, reliability, and simplicity. 相似文献
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将"九曲红梅"红茶(以下简称红茶)与卷烟烟丝样品分别经过粉碎并通过0.177mm网筛,制成分析用样品。称取0.2mg样品,在裂解炉中,温度为200℃的条件下,在氦气氛围中,样品挥发性成分瞬间气化,由载气带入气相色谱-质谱仪器系统,经分离和测定,得到了两种样品在此条件下所释放出成分。烟丝样品在此加热不燃烧条件下,释放的物质主要有人为添加的发烟剂丙三醇(59.34%),以及其本身的组分烟碱(20.34%)、3-丁炔-1-醇(4.32%)、5-羟甲基糠醛(3.23%)和2,3-二氢-3,5-二羟基-6-甲基-4(H)-吡喃-4-酮(2.12%)等。红茶样品中释放出的主要成分有咖啡因(86.23%)以及16种低含量特征组分。将此红茶样品按质量百分比为5%,10%,30%的比例加入卷烟烟丝中,并测定其在加热不燃烧的条件下释放物质量的变化,并结合感官评价。结果发现:混入不同比例红茶的烟丝,加热后释放出的气体中咖啡因的含量按茶叶的配比量的增加依次为0.71%,1.96%,7.23%;感官评价表明红茶加入卷烟烟丝中,提升了卷烟烟气的优雅感,强化了卷烟的果香、甜香、花香等香韵,提升了香气量和香气丰富性,细腻柔和烟气,改善余味,增强回甜感。当茶叶的加入量为10%时,在余味和口感上有较好的效果,具有全面提升感官品质的功效,整体抽吸舒适性和协调性较好,香气的质和量适中。 相似文献
186.
0.100 0g的甘草提取物样品用10mL的80%(体积分数)甲醇溶液超声提取30min后静置30min,取上清液经0.45μm滤膜过滤。采用高效液相色谱法同时测定滤液中14种活性成分的含量,以Diamonsil Plus C18色谱柱为分离柱,用0.05%(体积分数)磷酸溶液和乙腈以不同比例混合的溶液为流动相进行梯度洗脱,用二极管阵列检测器测定。通过单因素试验和L9(33)正交试验对提取条件进行了优化。14种活性成分的质量浓度在一定范围内与其对应的峰面积呈线性关系,方法的检出限(3s)为0.02~0.12 mg·L^-1。在3个浓度水平进行加标回收试验,回收率为91.7%~143%,测定值的相对标准偏差(n=5)为1.2%~6.0%。 相似文献
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A method for the determination of Pb isotope ratios (IR) in cigarette tobacco by quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS) has been developed and applied to tobacco samples from genuine and counterfeit cigarettes obtained in the USA. The IR 207Pb/206Pb, 208Pb/206Pb, 206Pb/204Pb, 207Pb/204Pb and 208Pb/204Pb were measured using a Q-ICP-MS instrument. Two certified reference materials, grown in the USA and Bulgaria, were also analysed for comparison with the tobacco samples, as were tobacco samples from cigarettes obtained in Pakistan and China. The precision of the results was sufficient to distinguish between the counterfeit and genuine USA cigarettes. All of the genuine cigarettes and both reference materials, grown in different regions, were statistically distinct based on the measured ratios. The counterfeit cigarettes were indistinguishable from the reference material grown in Bulgaria. The technique shows promise as a method for identifying counterfeit cigarettes, possibly determining the source region. 相似文献
189.
Marija Banoi Ines Banjari Ivana Flanjak Mate Patar Jelena Vladi Stela Joki 《Molecules (Basel, Switzerland)》2021,26(14)
This study intends to valorize by-products of the industrial processing of tobacco to obtain nicotine and phenolics as value-added compounds. Three influential parameters of the microwave-assisted extraction-MAE (temperature, treatment time, and solvent/solid ratio) were studied for the optimization of the extraction protocol for tobacco leaves and three types of waste—scrap, dust, and midrib, respectively. Nicotine was the dominant bioactive compound in all extracts, ranging from 1.512 to 5.480% in leaves, 1.886 to 3.709% in scrap, 2.628 to 4.840% dust, and 0.867 to 1.783% in midrib extracts. Five phenolic compounds were identified and quantified, predominated by chlorogenic acid and rutin. Additionally, total phenol content and antioxidant activity were determined using spectrophotometric assays. Optimization was performed in two aspects: to obtain a maximum extraction yield with minimum nicotine content and to obtain a maximum extraction yield with maximum nicotine content. These findings demonstrate that tobacco waste is a valuable source of bioactive compounds and MAE can be a promising alternative technique to obtain extracts rich in targeted bioactive compounds, especially nicotine. 相似文献
190.
提出利用聚类方法对光谱数据进行特征筛选。通过分析类内参数γ1和类间参数γ2对筛选结果的影响,选择较好的γ1和γ2进行有用光谱特征筛选。利用烤烟叶的近红外反射光谱(1500~2400 nm间隔2 nm),选用SVM方法进行部位和颜色分组识别,训练样本的识别率为100%,测试样本的识别率分别是96.22%和92.79%。然后利用聚类方法对初始光谱进行特征筛选,选用相同的 SVM 方法及相同的学习样本和测试样本进行部位和颜色分组识别。在删减部分不相干光谱后,识别率分别提高到97.23%和95.52%;继续删除相关度不高的光谱,在识别率略有下降时,光谱特征数可减少到200个以下。结果表明:利用聚类方法进行特征筛选,不仅可提高识别率,且可大大减少光谱数据,因而极大地减少了数据采集时间,简化了分组模型,提高了系统的实时和快速处理能力。 相似文献