共查询到19条相似文献,搜索用时 406 毫秒
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连续流动法测定烟草水溶性糖的影响因素 总被引:1,自引:0,他引:1
为提高RFA-300连续流动分析仪测定烟草及烟草制品中水溶性糖含量的准确性.依据行业标准YC/ T159—2002对各种影响因素进行了考察,发现标准样品的种类、纯度及反应时间是主要影响因素,并根据试验结果和测试原理的要求对仪器管路进行了适当的加长。确定了以葡萄糖为标样.采用校正标样和加长仪器管路的连续流动法测定烟草制品中的水溶性糖。结果表明,改进后方法的回收率为98.8%-107.9%,变异系数为1.63%. 测定结果与芒森·沃克法的基本一致。 相似文献
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连续流动分析法在烟草分析中的应用 总被引:12,自引:0,他引:12
连续流动分析法(CFA)作为一种快速、准确的批量检测方法已经广泛应用于国内外烟草行业。根据连续流动分析法的原理,详细介绍了该分析法在烟草中对烟碱、总糖及还原性糖、水溶性糖、总氮、蛋白质、氯以及钾等含量的测定方法及应用,并对连续流动分析法在烟草科学技术中的应用做了展望。 相似文献
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连续流动分析法在葡萄酒总糖检测中的应用 总被引:1,自引:0,他引:1
采用连续流动分析法对不同类型的葡萄酒中的总糖进行了检测,并对连续流动法与费林法测定葡萄酒中的总糖结果进行比较分析,结果显示,两种检测方法的结果精密度和重现性没有差异。日常使用和检测结果数据显示,连续流动分析法测定葡萄酒中的总糖操作简单、自动化程度高,且检测结果准确度可靠、精密度高和重现性完全符合实验室质量控制规范的要求,可以广泛应用于葡萄酒中总糖含量的测定。 相似文献
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《计量与测试技术》2017,(12)
为提高连续流动微流模块分析仪烟草总氮的检测结果准确性,依据JJF 1059.1-2012《测量不确定度评定与表示》,对连续流动微流法测定烟草中总氮的测量不确定度进行了评定。采用因果关系图系统分析影响不确定度的各因素,在此基础上构建了微流法测量不确定度的评定方案,并通过测量模型评定了各不确定度分量。结果表明:(1)总氮的测定值为1.56%,在95%包含概率下其扩展不确定度分别为0.05%;(2)影响测量不确定度的因素主要有标准溶液配制、测量重复性、最小二乘法校准曲线拟合;(3)采用称量法配制标准溶液、选择合适的标准工作溶液浓度范围,可进一步提高分析的精准度。 相似文献
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转拟南芥AtNHX1基因促进烟草对钾吸收的研究 总被引:1,自引:0,他引:1
提取拟南芥总RNA,反转录合成Na /H 逆向转运蛋白基因AtNHX1,构建了植物高效表达载体,用叶盘法将其导入烟草,经筛选获得了抗卡那霉素和GUS染色阳性的转化子38株.应用荧光定量PCR方法对转化材料部分含AtNHX1基因的烟草内源钾通道基因、烟草K 转运蛋白基因和烟草焦磷酸酶基因的转录水平进行了分析.结果表明:在转化烟草中可以检测到AtNHX1基因mRNA,与未转化材料相比,烟草钾离子转运蛋白基因NtHAK1的转录降低,H -ATPase基因NHA1转录增加,钾通道基因NKT转录无显著变化,T1代转化烟叶中K 含量显著增加,Na 、Ca2 无显著变化,烟叶中总糖含量降低,证明了编码拟南芥AtNHX1基因与植物的K 吸收有关. 相似文献
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Research on automatic identification system of tobacco diseases 总被引:2,自引:0,他引:2
Yuanyuan Shao Guantao Xuan Yangyan Zhu Yanling Zhang Hongxing Peng Zhongzheng Liu 《成像科学杂志》2017,65(4):252-259
In order to improve recognition accuracy of tobacco diseases, an identification method based on multi-feature and genetic algorithms optimizing BP neural network was proposed. First, Otsu method was used to obtain disease location information and GrabCut function was initialized for extracting diseased area effectively. Second, colour moments, disease contour and GLCM were used to get colour, multi-contour and texture features. Once again, BP neural network was optimized by genetic algorithm, and the optimal initial weights and thresholds were obtained, which shortened the training time and improved the accuracy of disease identification. Finally, BP neural network model for tobacco diseases diagnosis was established with the mobile client as input and the user services as output. The field experiment showed that the method could diagnose eight types of tobacco diseases effectively and automatically. The average recognition accuracy rate of selected tobacco diseases was about 92.5%. 相似文献
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烟草制丝过程中生物碱的变化研究 总被引:2,自引:0,他引:2
采用毛细管气相色谱分离、氢火焰离子化检测,分析了卷烟制丝过程中松片回潮、润叶加料、烘丝三个关键生产工序前后的总生物碱和游离生物碱的含量变化。研究结果表明,高温烘丝工序对总生物碱和游离生物碱的降低最为显著,润叶加料工序次之,松片回潮工序变化幅度最小。这三个关键卷烟制丝加工工艺过程中总生物碱的降低幅度达15%,游离生物碱降低达25%。试验研究结果对卷烟制丝工序质量评价、合理控制产品内在质量及其稳定性,具有一定理论指导意义和实际应用价值。 相似文献
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采用顶空液相微萃取法(HS-LPME)对8个不同批次及掺兑不同比例其他烟用香精香料的1148#样品的挥发性成分进行提取并用气相色谱法分析,同时研究了不同萃取溶剂、萃取时间、萃取温度对分析结果的影响,确定了最佳条件:样品在70℃下平衡1.0h,搅拌速度300r/min,以4.0μL正十二烷作萃取剂,萃取时间为10min,并通过主成分分析(PCA)法对不同批次及掺兑样品进行模式识别。结果表明:此法能成功地将掺兑样品区分开来,可以成为烟用香精香料1148#质量控制的有效手段之一。 相似文献
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Concentrations of polycyclic aromatic hydrocarbons (PAHs) in tobacco smoke of 12 commercial brand cigarettes were determined in a simulated chamber of 20.25 m3 in size. The total concentrations of 17 PAHs (summation operatorPAHs) in the chamber were 3500 and 1152 ng/m3 in vapor phase and particulate phase, respectively. In vapor phase, the yield of naphthalene (NA) appeared to be the most abundant (2462 ng/cig) followed by fluorene (FLUOR) and acenaphthylene (ACY), while the yield of benzo[ghi]perylene (BP) was the most abundant (259.7 ng/cig) in particulate phase followed by phenanthrene (PHEN) and FLUOR. The proportion of PAHs in particulate phase increased with increasing molecular weight. PAHs with two to six rings accounted for 40.2%, 35.3%, 11.7%, 7.6%, 5.2% of summation operatorPAHs, respectively. There was no obvious correlation between PAHs, benzo[a]pyrene (BaP) concentrations in tobacco smoke and smoking tar contents, nicotine contents. With the source fingerprint of PAHs in tobacco smoke, NA could be regarded as the marker of tobacco smoke source because of its largest contribution to summation operatorPAHs (40.2%), followed by FLUOR (12.7%) and ACY (9.8%). Further study indicated that more than 80% of BaP in indoor air of resident homes in Hangzhou was from tobacco smoke. 相似文献
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将苏云金芽孢杆菌cry1Aa的C端编码区截短,获得编码N端609个氨基酸约1.8kb的核心毒素基因,将其构建到植物表达载体转化烟草,研究直接表达的活性ICP核心毒素被昆虫取食后的杀虫效果.T1代种子发芽的抗生素抗性分离和PCR检测证实cry1Aa核心毒素基因整合到了烟草基因组,Western 杂交检测表明转化烟草能够正常表达大小为75.6kD的核心毒素蛋白.生物测定结果表明,转化烟草对初孵棉铃虫平均有高于60%的致死率,对初孵甜菜夜蛾平均达到70%的致死率,最高致死率均可达到90%以上,并对昆虫的生长发育有明显的抑制作用. 相似文献
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V. P. Misnik I. G. Korateev V. F. Trubnikov 《Journal of Engineering Physics and Thermophysics》1980,38(1):103-106
Analytical results are presented on the mass-transfer characteristics of tobacco leaves.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 38, No. 1, pp. 145–149, January, 1980. 相似文献
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Yadav AK Kaushik CP Haritash AK Singh B Raghuvanshi SP Kansal A 《Journal of hazardous materials》2007,142(1-2):77-80
Levels of water soluble and acid soluble fluoride in tea, toothpaste, tobacco and pan masala (mouth freshener) were estimated. These items are, generally, ignored while calculating the total dietary intake of fluoride. Tea, toothpaste, tobacco, pan masala (with tobacco and without tobacco) frequently expose human body to 3.88-137.09, 53.5-338.5, 28.0-113.0, 16.5-306.5 and 23.5-185.0 microg of fluoride per gram of these items, respectively. An effort was also made to quantify, on the basis of available studies, the probable human ingestion of fluoride through these substances. Increased leaching of fluoride from some of these substances has been observed in acidic conditions in the present study. The results can be extrapolated to acidic conditions of human stomach. 相似文献