排序方式: 共有53条查询结果,搜索用时 31 毫秒
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建立高效液相色谱法快速测定环境空气中13种醛酮类化合物的方法。选用Poroshell 120 SB–C_(18)色谱柱(250 mm×4.6 mm,4μm)为分离柱,以水–乙腈溶液为流动相,梯度洗脱,流量为1.5 mL/min,柱温为50℃,进样体积为10μL,采用紫外检测器检测,检测波长为360 nm。13种醛酮类化合物的质量浓度在0.05~2.0μg/mL范围内与色谱峰面积具有良好的线性关系,相关系数均不小于0.9998,方法检出限为0.16~0.47μg/m³。空白样品加标回收率为97.2%~101.1%,测定结果的相对标准偏差为0.5%~4.3%(n=6)。该方法分析速度快,准确度和灵敏度高,精密度好,适用于环境空气中醛酮类化合物的快速测定。 相似文献
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Experimental analysis of sand particles' lift-off and incident velocities in wind-blown sand flux 总被引:2,自引:1,他引:2
The probability distributions of sand particles' lift-off and incident velocities in a wind-blown sand flux play very important roles in the simulation of the wind-blown sand movement. In this paper, the vertical and the horizontal speeds of sand particles located at 1.0 mm above a sand-bed in a wind-blown sand flux are observed with the aid of Phase Doppler Anemometry (PDA) in a wind tunnel. Based on the experimental data, the probability distributions of not only the vertical lift-off speed but also the lift-off velocity as well as its horizontal component and the incident velocity as well as its vertical and horizontal components can be obtained by the equal distance histogram method. It is found, according to the results of the χ 2-test for these probability distributions, that the probability density functions (pdf's) of the sand particles' lift-off and incident velocities as well as their vertical components are described by the Gamma density function with different peak values and shapes and the downwind incident and lift-off horizontal speeds, respectively, can be described by the lognormal and the Gamma density functions. These pdf's depend on not only the sand particle diameter but also the wind speed. 相似文献
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采用4%聚乙二醇(PEG)-20M 1%KOH和GXD-401为固定相,2m×3mm玻璃填充柱分离三甲胺,FID检测.结果表明:在柱温140℃,进样口温度180℃,检测器温度180℃,氮流量30mL·min-1时,平均回收率为100.13%,相对标准偏差为3.0%.该方法有较高灵敏度和良好的线性关系. 相似文献
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建立气相色谱法测定环境空气中丙烯醇的方法。用蒸馏水吸收环境空气中的丙烯醇,以DB–624色谱柱(30 m×0.53 mm,3μm)为分离色谱柱,用氢火焰离子化检测器检测丙烯醇的含量。当采样体积为30 L时,丙烯醇的检出限为0.01 mg/m~3,样品加标回收率为93.0%~97.4%,测定结果的相对标准偏差小于2%(n=7)。该方法前处理简便,分析灵敏度高,分析过程中避免了有机溶剂的使用,无二次污染,适用于环境空气中丙烯醇的监测。 相似文献
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空气自动监测系统的管理 总被引:2,自引:0,他引:2
介绍象山县环境空气自动监测站自2005年11月建立以来的运行情况,以及在制定管理制度和质量控制措施方面积累的一些经验。 相似文献