排序方式: 共有44条查询结果,搜索用时 62 毫秒
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气相色谱法测定油炸、烘烤食品中丙烯酰胺——丙烯酰胺污染水平调查 总被引:2,自引:0,他引:2
从市场上购得12种具有中国传统特色的油炸及烘烤食品,从中取得样品48个,经萃取、溴化及蒸缩等前处理步骤后对其中的丙烯酰胺含量用气相色谱法进行检测。在气相色谱法分析中采用Elite Wax毛细管色谱柱及电子捕获检测器,分析结果表明:在这些样品中均存在一定量的丙烯酰胺(3~1396μg.kg-1范围内)。对此类食品加工方法提出了改进方案以期能降低丙烯酰胺的含量。试验中发现将氽油条的油温降低至175℃可明显降低油条中丙烯酰胺的含量,但油炸之前在原料(面粉)中加入抗氧化剂(如VC及VE),对降低丙烯酰胺含量并无效果。 相似文献
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This paper investigates robust filter design for linear discrete-time impulsive systems with uncertainty under H∞ performance. First, an impulsive linear filter and a robust H∞ filtering problem are introduced for a discrete-time impulsive systems. Then,a sufficient condition of asymptotical stability and H∞ performance for the filtering error systems are provided by the discrete-time Lyapunov function method. The filter gains can be obtained by solving a set of linear matrix inequalities (LMIs). Finally, a numerical example is presented to show effectiveness of the obtained result. 相似文献
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采用沉积的方法在镁合金AZ31表面制备植酸转化膜并研究了pH值的影响. 利用极化曲线和电化学阻抗谱方法测定其耐腐蚀性能,用扫描电子显微镜观察转化膜的表面微观结构,用能谱测定转化膜的组成元素. 在理论上通过热力学的方法分析最佳pH值. 植酸转化膜可以提高镁合金AZ31的耐腐蚀性能. 当植酸溶液的pH=5时腐蚀效率达到了89.19%,此时腐蚀电位正移了156 mV,腐蚀电流密度与没有处理的试样相比减小了约一个数量级. 热力学分析表明植酸转化膜的耐腐蚀性能不仅受植酸根离子和镁离子浓度的影响,也与氢气释放的速率有关. 相似文献
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针对矿山大型排土场所出现的滑坡等工程环境灾害的预测与防治问题,着重探讨排土场边坡失稳破坏预测问题.文中采用Fuzzy数学中的Fuzzy概率测度理论建立理论预测分析模型,并对大型排土场边坡失稳破坏的Fuzzy概率测度进行具体的预测分析,所获结果与已有的经典分析方法所获理论结果一致.针对矿山大型排土场所出现的滑坡等工程环境灾害防治问题,提出了具体的防治技术措施. 相似文献
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Su Wang Hua-jie Gou Bing-cheng Fan Yu-zhong He Sheng-tao Zhang Ji-ping Cui 《化学物理学报(中文版)》2007,20(1):48-52
JP-10 (exo-tetrahydrodicyclopentadiene, C10H16) ignition delay times were measured in a preheated shock tube. The vapor pressures of the JP-10 were measured directly by using a high-precision vacuum gauge, to remedy the difficulty in determining the gaseous concentrations of heavy hydrocarbon fuel arising from the adsorption on the wall in shock tube experiments. The whole variation of pressure and emission of the OH or CH radicals were observed in the ignition process by a pressure transducer and a photomultiplier with a monochromator. The emission of the OH or CH radicals was used to identify the time to ignition. Experiments were performed over the pressure range of 151-556 kPa, temperature range of 1000-2100 K, fuel concentrations of 0.1%-0.55% mole fraction, and stoichiometric ratios of 0.25, 0.5, 1.0 and 2.0. The experimental results show that for the lower and higher temperature ranges, there are different dependency relationships of the ignition time on the temperature and the concentrations of JP-10 and oxygen. 相似文献
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