排序方式: 共有35条查询结果,搜索用时 46 毫秒
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通过均匀设计法安排试验,利用计算机回归分析科学地建立了三种邻苯二甲酸酯类物质———邻苯二甲酸二(2-乙基己基)酯(DEHP)、邻苯二甲酸二甲酯(DMP)、邻苯二甲酸二丁酯(DBP)的峰面积与分流比、升温速率之间的非线性数学模型。由此建模分析得到了分流比和升温速率对三种分析物峰面积的不同影响效果,为科学确立三种分析物的色谱检测条件奠定了基础。 相似文献
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Aquatic toxicity of di (2-eihylhexyl) phthalate to duckweeds 总被引:1,自引:0,他引:1
This study is concerned with the effects of di (2-ethylhexyl) phthalate (DEHP) on two kinds of duckweeds (Spirodela polyrhiza and Lemna minor).The results indicate that DEHP has aquatic toxicity to Spirodela polyrhiza at 0.4 mg/L and to Lemna minor at over 0.1 mg/L by changing their physiologic-biochemical characteristics.The contents of duckweed chlorophyll and soluble protein decrease with increasing DEHP concentration after 7 d of exposure.DEHP shows the stimulating role in catalase (CAT) and superoxide dismutase (SOD) systems at relative low levels.At 0.01 mg/L and 0.005 mg/L,SOD activities of Spirodela polyrhiza and Lemna minor reach their peak values respectively,while CAT activity reaches its maximum value at 0.05 mg/L and 0.01 mg/L.When DEHP levels are too high,the protection enzyme system would be destroyed and plant growth is inhibited.The analysis of malondialdehyde (MDA) and Fourier transform infrared spectroscopy manifest that DEHP could affect the tested duckweeds by destroying its cell membranes,and Spirodela polyrhiza is more resistant to DEHP exposure than Lemna minor. 相似文献
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《实验室研究与探索》2015,(9)
采用微波辅助提取和常规的气相色谱分离方法,对农用棚膜中6种邻苯二甲酸酯类(PAEs)增塑剂的检测进行了实验研究。选用正己烷作为提取剂,利用单因素和正交实验对提取条件进行了优化,棚膜样品破碎至1.0 cm×2.0 cm,料液比(m L/g)1∶50,微波功率400 W,萃取时间8 min能获得最佳提取效果。采用气相色谱法,在DB-5MS(30 m×0.25 mm×0.25μm)色谱柱上利用程序升温对样品进行分离,氢火焰离子化检测器进行检测。该方法在2.0~1 000 mg/L范围具有良好线性关系,相关系数均大于0.999,检测限0.15~0.60 mg/kg,符合国家限量标准,样品加标回收率85.4%~110.7%,相对标准偏差0.61%~7.47%。该方法操作简单,灵敏度高,不仅可以满足农用棚膜中邻苯二甲酸酯类化合物的分析检测,并可应用于本科生仪器分析实验教学。 相似文献
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