为了评估乌鳢中四环素类药物的残留风险,建立了乌鳢肌肉中4种四环素类药物残留的快速、简单、廉价、高效、耐用和安全的前处理方法(Quick、Easy、Cheap、Effective、Rugged、Safe,QuEChER)。采用Box–Behnken design(BBD)响应面优化法,...为了评估乌鳢中四环素类药物的残留风险,建立了乌鳢肌肉中4种四环素类药物残留的快速、简单、廉价、高效、耐用和安全的前处理方法(Quick、Easy、Cheap、Effective、Rugged、Safe,QuEChER)。采用Box–Behnken design(BBD)响应面优化法,优化了提取和净化条件。样品经10 mL 1%甲酸酸化乙腈和2 mL 0.1 mol/L Na2EDTA-McIlvaine缓冲溶液提取,以150 mg PSA和200 mg C18进行净化,采用超高效液相色谱-串联质谱法(Ultra-high performance liquid chromatography-tandem mass spectrometry,UPLC-MS/MS)检测。结果表明,该方法在0.50~100 ng/mL浓度范围内线性良好(r≥0.999),检出限(Limit of Detection,LOD)和定量限(Limit of Quantitation,LOQ)分别为0.25~0.75μg/kg和0.84~2.00μg/kg。在乌鳢肌肉中四环素、土霉素、金霉素和多西环素的平均回收率在89.5%~1187%之间,相对标准偏差(RSD)在1.11%~8.88%之间。该方法简便、灵敏、准确,可用于乌鳢中四环素含量的快速测定。展开更多
Light pen coordinate measuring system(LPCMS)is a kind of portable coordinate measuring technique based on vision metrology.In classical LPCMS,the measuring range is limited to the camera’s field of view.To overcome t...Light pen coordinate measuring system(LPCMS)is a kind of portable coordinate measuring technique based on vision metrology.In classical LPCMS,the measuring range is limited to the camera’s field of view.To overcome this defect,a new LPCMS is designed in this paper to fulfil whole space coordinate measurement.The camera is installed on a turntable instead of a tripod,so that the camera can rotate to track the movement of the light pen.The new system can be applied to large scale onsite measurement,and therefore it notably extends the application of LPCMS.To guarantee the accuracy of the new system,a method to calibrate the parameters of the tracking turntable is also proposed.Fixing the light pen at a stationary position,and changing the azimuth angles of the turntable’s two shafts,so that the camera can capture the images of the light pen from different view angles.According to the invariant spatial relationship between the camera and the pedestal of the tracking turntable,a system of nonlinear equations can be established to solve the parameters of the turntable.Experimental results show that the whole space coordinate measuring accuracy of the new system can reach 0.25 mm within 10 m.It can be concluded that the newly designed system can significantly expand the measuring range of LPCMS without losing too much accuracy.展开更多
文摘为了评估乌鳢中四环素类药物的残留风险,建立了乌鳢肌肉中4种四环素类药物残留的快速、简单、廉价、高效、耐用和安全的前处理方法(Quick、Easy、Cheap、Effective、Rugged、Safe,QuEChER)。采用Box–Behnken design(BBD)响应面优化法,优化了提取和净化条件。样品经10 mL 1%甲酸酸化乙腈和2 mL 0.1 mol/L Na2EDTA-McIlvaine缓冲溶液提取,以150 mg PSA和200 mg C18进行净化,采用超高效液相色谱-串联质谱法(Ultra-high performance liquid chromatography-tandem mass spectrometry,UPLC-MS/MS)检测。结果表明,该方法在0.50~100 ng/mL浓度范围内线性良好(r≥0.999),检出限(Limit of Detection,LOD)和定量限(Limit of Quantitation,LOQ)分别为0.25~0.75μg/kg和0.84~2.00μg/kg。在乌鳢肌肉中四环素、土霉素、金霉素和多西环素的平均回收率在89.5%~1187%之间,相对标准偏差(RSD)在1.11%~8.88%之间。该方法简便、灵敏、准确,可用于乌鳢中四环素含量的快速测定。
基金State Administration of Science,Technology and Industry for the National Defense(No.JSJL2014206B001)。
文摘Light pen coordinate measuring system(LPCMS)is a kind of portable coordinate measuring technique based on vision metrology.In classical LPCMS,the measuring range is limited to the camera’s field of view.To overcome this defect,a new LPCMS is designed in this paper to fulfil whole space coordinate measurement.The camera is installed on a turntable instead of a tripod,so that the camera can rotate to track the movement of the light pen.The new system can be applied to large scale onsite measurement,and therefore it notably extends the application of LPCMS.To guarantee the accuracy of the new system,a method to calibrate the parameters of the tracking turntable is also proposed.Fixing the light pen at a stationary position,and changing the azimuth angles of the turntable’s two shafts,so that the camera can capture the images of the light pen from different view angles.According to the invariant spatial relationship between the camera and the pedestal of the tracking turntable,a system of nonlinear equations can be established to solve the parameters of the turntable.Experimental results show that the whole space coordinate measuring accuracy of the new system can reach 0.25 mm within 10 m.It can be concluded that the newly designed system can significantly expand the measuring range of LPCMS without losing too much accuracy.