实验室标准物质的期间核查

结合实验室标准物质期间核查的工作实际,对硫标准物质期间核查方法进行了探讨,并对核查的注意事项进行了说明。     

高流动性等规聚丙烯与高密度聚乙烯共混改性

研究了高密度聚乙烯(HDPE)含量对等规高流动性聚丙烯(iPP)力学性能和流动性能的影响。研究表明,随着HDPE含量的增大,冲击强度越来越大,硬度越来越小。HDPE含量为10%时,拉伸/屈服强度以及弯曲强度出现最大值。共混体系的流动性能随着HDPE含量的增大而减小。     

24％噻呋酰胺悬浮剂的反相高效液相色谱测定

采用反相高效液相色谱外标法,以甲醇-水作为流动相,用C18柱和紫外检测器（230nm）测定了24％噻呋酰胺悬浮剂的含量.结果表明：方法的标准偏差为0.09,变异系数为0.37％,平均回收率为99.35％,线性相关系数为0.999.     

浅析不同材质复合膜透氧量与温度的关系

通过对复合膜透氧原理的介绍及其制备工艺的描述,研究了几种常用复合包装膜的透氧量与温度变化关系。结果表明：温度升高,复合膜的透氧量增大;其中,BOPA／LDPE复合膜的阻气性最佳,BOPP／LDPE的阻气性较差。     

洗涤剂中大肠菌群检测方法的探讨与分析

大肠菌群是洗涤剂产品关键的卫生指标,表明产品被粪便污染的程度。对洗涤剂样品中大肠菌群按三种不同的检测方法进行检测,分析讨论不同检测方法对结果的影响。     

菜籽饼粕有机肥的应用

菜籽饼粕是优良的有机肥料,可以提升土壤肥力,它含有的营养元素和活性物质为作物生长发育提供必需营养,改善农产品品质。对菜籽饼粕有机肥的肥效优势及其应用进行了综述,展望了菜籽饼粕有机肥的应用前景。     

油炸食品中丙烯酰胺的安全性分析

阐述了食品中丙烯酰胺产生的机理,丙烯酰胺形成的主要原因,食品中丙烯酰胺的主要分析方法,对丙烯酰胺的毒理学和食用含有丙烯酰胺食品的风险进行了讨论,并提出了相关的安全性对策措施。     

Analysis of metabolic markers of tea origin by UHPLC and high resolution mass spectrometry

Tea is an infusion made from the dried leaves of Camellia sinensis L. and is the second most consumed beverage in the world. It has been shown that factors such as fermentation methods, cultivar, geographical origin and season can affect the biochemical composition of tea. In this study, the biochemical composition of green, oolong and black commercial tea samples from around the world was studied using a non-targeted method utilising reversed phase ultra high pressure liquid chromatography (UHPLC) and high resolution mass spectrometry. Principal component analysis of green, oolong and black tea extracts clearly showed that fermented tea can be resolved from non-fermented tea. When the non-targeted data were combined with the supervised multivariate technique, partial least squares discriminant analysis, the method was able to clearly distinguish ‘country of origin’ within green tea and to a lesser extent within a black tea sample set, plus provide indicative marker ions for the country of origin. Many of the significant components detected in this study are unknowns, emphasising the importance of un-biased non-targeted analytical techniques. This study highlights the potential efficacy of non-targeted UHPLC–mass spectrometry when combined with multivariate statistics to differentiate fermented from non-fermented tea and provide potential indicators of provenance of tea samples for further examination.     

仿真饰品中有害物质的研究现状

概述了仿真饰品中的有害物质及其危害,对有害物质的研究方法进行了探讨,并提出了减少当前仿真饰品中有害物质危害的解决措施。     

外墙保温材料的种类及防火性能分析

讨论了常见外墙保温材料的主要种类,按照国家有关标准对各种材料进行防火性能实验,对外墙保温材料的防火性能进行分析与讨论。