共查询到15条相似文献,搜索用时 78 毫秒
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将不同茶叶直接添加于卷烟烟丝中,收集萃取烟气中的烟碱和咖啡碱,用紫外分光光度法定量分析主流烟气中烟碱以及咖啡碱的变化。结果表明,茶叶能够有效的影响烟气烟碱含量,其中当绿茶添加量为20%时烟气的咖啡碱含量达到最大,同时烟碱含量降到最小。 相似文献
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烟丝的pH值的升高,能提高烟气pH值与烟碱/焦油值,同时增加了烟气游离烟碱的含量,提高烟碱的转移率;此外对卷烟的感官品质也产生了一定的影响。 相似文献
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通过在卷烟滤嘴中添加柠檬酸二乙酯,在不改变烟支物理状态的条件下,能够有选择性降低主流烟气的烟碱,而基本不改变焦油等其他烟气常规成分。同时卷烟感官评价结果表明添加柠檬酸二乙酯对卷烟烟气劲头、刺激、细腻程度、干燥感、杂气等都有一定的改善作用。 相似文献
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反相HPLC法测定卷烟烟气中的烟碱 总被引:2,自引:0,他引:2
采用反相HPLC法测定卷烟烟气总粒相物中烟碱的含量,流动相为水:H3PO4 - KH2PO4(50:50)缓冲液,检测波长λ=262nm ,线性范围:7 ~100mg/50ml。实验证明,该方法的准确度高,精密度好,可作为检测烟碱的可靠方法 相似文献
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《云南化工》2017,(1):22-25
为了考察不同卷烟机对卷烟烟气成分稳定性的影响,选取了protos70、90、M5等3种卷烟机各5台,研究了相同生产条件下不同卷烟机所生产卷烟的焦油、烟气烟碱和一氧化碳量的差异性,并对检测结果进行了统计分析和t检验。结果表明,同机型卷烟机的3项指标均为protos90protos70protos M5,且不同机型的机台间极差大于相同机型的机台间极差。t检验表明,protos90与protos M5间的差异最大,三项指标的差异性均为极显著;其次是protos90与protos70,焦油量的差异性为显著,烟气烟碱量的差异性为极显著;protos70与protos M5间的差异最小,只有烟气烟碱量的差异性为极显著。因此,利用多机型、机台卷烟机生产同牌号卷烟时,机型是影响烟气成分稳定性的重要因素。 相似文献
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Khosbayar Lkhagvadorj Zhijun Zeng Karolin F. Meyer Laura P. Verweij Wierd Kooistra Marjan Reinders-Luinge Henk W. Dijkhuizen Inge A. M. de Graaf Torsten Plsch Machteld N. Hylkema 《International journal of molecular sciences》2021,22(1)
Prenatal smoke exposure (PreSE) is a risk factor for nicotine dependence, which is further enhanced by postnatal smoke exposure (PostSE). One susceptibility gene to nicotine dependence is Cytochrome P450 (CYP) 2A6, an enzyme responsible for the conversion of nicotine to cotinine in the liver. Higher CYP2A6 activity is associated with nicotine dependence and could be regulated through DNA methylation. In this study we investigated whether PostSE further impaired PreSE-induced effects on nicotine metabolism, along with Cyp2a5, orthologue of CYP2A6, mRNA expression and DNA methylation. Using a mouse model where prenatally smoke-exposed adult offspring were exposed to cigarette smoke for 3 months, enzyme activity, mRNA levels, and promoter methylation of hepatic Cyp2a5 were evaluated. We found that in male offspring, PostSE increased PreSE-induced cotinine levels and Cyp2a5 mRNA expression. In addition, both PostSE and PreSE changed Cyp2a5 DNA methylation in male groups. PreSE however decreased cotinine levels whereas it had no effect on Cyp2a5 mRNA expression or methylation. These adverse outcomes of PreSE and PostSE were most prominent in males. When considered in the context of the human health aspects, the combined effect of prenatal and adolescent smoke exposure could lead to an accelerated risk for nicotine dependence later in life. 相似文献
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采用锥形量热仪比较了溴系阻燃聚丙烯、无卤阻燃聚丙烯的燃烧行为。结果表明:按UL94标准测试V-0阻燃等级的阻燃聚丙烯复合材料,采用无卤阻燃体系比采用溴系阻燃体系具有更低的热释放速率、烟生成速率和总烟释放量。 相似文献
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根据实践经验,总结出若干建筑工程防排烟系统设计中容易忽视的问题,提出值得借鉴的经验和需要吸取的教训,以便引起广大审核人员特别是初学者的注意,防止类似的错误发生。 相似文献