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首先用238Pu同位素稀释法标定了四水硫酸钚中239Pu的比活度,再用该239Pu溶液作稀释剂,对242Pu稀释剂进行标定,得到242Pu的比活度平均值为1 304 Bq/g,相对合成标准不确定度为1.4%.钚的同位素丰度比(R(239Pu/242Pu))为0.002 26,相对合成标准不确定度为4%;R(240Pu/242Pu)为0.017 2,相对合成标准不确定度为1%. 相似文献
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HPLC-UV同时测定皮革中三种含氯苯酚 总被引:1,自引:0,他引:1
建立并验证了用HPLC-UV测定皮革中含氯苯酚的方法;以丙酮为溶剂,采用超声波提取法提取皮革中含氯苯酚,以相对保留时间定性,峰面积进行定量;该方法平均回收率为97.20%~103.11%,RSD为1.094%~1.377%,检测限(S/N=3)分别为2,3,5,6-四氯苯酚:0.014 mg/L,五氯苯酚:0.002 mg/L,2,4,6-三氯苯酚:0.004 mg/L;本方法具有方便快捷、灵敏度高、回收率高、精密度好的特点,且避免了大量化学试剂的使用,减少了环境污染。 相似文献
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HPLC检测食品接触材料中双酚A的含量 总被引:1,自引:0,他引:1
建立并验证了利用HPLC检测食品接触材料中双酚A的含量。样品经3%(质量分数)的乙酸溶液70℃浸泡2h,过滤浸泡液于4℃避光保存,HPLC测试。结果显示,双酚A在0.1008~1008.2μg/mL的浓度范围内线性相关系数r2=0.9999,本方法平均回收率为85.78%~98.12%,相对标准偏差RSD为0.97%~1.61%,该方法检测限(S/N=3)为0.038mg/kg。本方法对于食品接触材料中双酚A的含量检测结果准确,操作方便,快捷,满足企业对该项指标的控制要求。 相似文献
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目的:建立并验证了用HPLC-UV测定电子电气产品中多溴联苯醚的检测方法;方法:以甲苯为溶剂,采用索氏萃取法提取电子电气产品中10种多溴联苯醚,以相对保留时间定性,色谱峰面积定量;结果:该方法平均回收率为92.39%~100.32%,RSD为0.994%~1.377%,检测限(S/N=3)分别为1-PBDE:0.037 mg·L-1;2-PBDE:0.035 mg·L-1;3-PBDE:0.044mg·L-1;4-PBDE:0.047 mg·L-1;6-PBDE:0.045 mg·L-1;5-PBDE:0.043 mg·L-1;7-PBDE:0.036 mg·L-1;9-PBDE:0.055 mg·L-1;8-PBDE:0.054 mg·L-1;10-PBDE:0.067 mg·L-1;结论:实验表明该方法对部分电子电气产品中多溴联苯醚含量的测定符合RoHS检测的要求。 相似文献
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The luminescent properties of Eu^3+doped Ca2SiO4 red phosphors synthesized by the flux fusion reaction method were investigated. It was found that the excitation spectrum included two regions: the weak excitation band below 325 nm and strong narrow peaks above 325 nm. The main peak of the excitation band was located at 400 nm. The peaks located at 290 nm were assigned to the combination of the charge transfer transition of O-Eu, peaks above 325 nm (325, 385, 400, 470, 511, and 539 nm) were assigned to the f-f transitions of Eu^3+. The emission spectrum was dominated by the red peak located at 612 nm due to the electric dipole transition of ^5D0-^7F2. In addition, the effects of the Eu^3+ content and charge compensators of Li^+, Na^+, K^+, and Cl^- ions on the emission intensity were investigated. The experiment results suggested that the strongest emission was obtained when the concentration of the Eu^3+ ions was 0.3 mol^-1, and Li^+ ions gave the best improvement to enhance the emission intensity. Ca2SiO4:Eu^3+, Li^+ was thus suitable for low-cost trichromatic white light emitting diodes (WLED) based on UV InGaN chip. 相似文献