主题：【已应助】ICP-OES强度管控

貌似仪器的强度不需要监控啊，因为你换了矩管或者换了雾化器强度就会变化。是否监控QC含量更合理？

如果要监控我觉得监控矩管准直Mn之类的元素强度是否更好？

早期做美泰玩具测试时候其内部标准GL0P7409《 ICP MAINTENANCE AND PERFORMANCE CHECKS》就有这样提到5.3 Daily Performance Check
The daily performance of the ICP machine shall be monitored by measuring the intensity value of
the control point standard solution and evaluating any trending per the charting procedures
stated below:
5.3.1 The Intensity Trend Chart is obtained by plotting the intensity value against the run
number on a line graph. Choose a concentration value that is used in the calibration
procedure (i.e. 0.05, 0.1 or 0.5 ppm for lead) when creating the Trend Chart (refers to
?5.4.1.3 for the updated calibration points). The intensity values shown below were
derived from middle range of standards in 20% nitric acid. 20 different readings from 20
different days should be recorded and graphed (see Figure 1).
X is the intensity value of the control point standard solution (middle range standard
solution of each element),
Xm is the mean intensity value of the control point standard solution which is collected 20
times on different days,
SD is the standard deviation of 20 measurements,
UCL is upper control limit, UCL=Xm  3SD; LCL is lower control limit, LCL=Xm-3SD; UWL
is upper warning limit, UWL=Xm 2SD; LWL is lower warning limit, LWL= Xm-2SD.
5.3.2 Daily ICP intensity for each element should be tested and reported on the ICP daily
intensity chart. An example of the ICP intensity chart is attached in Addendum 1.
Intensity trend chart should be reviewed every 6 months.
5.3.3 If two consecutive intensity values fall in the acceptance criteria area  2SD (-2SD) &
3SD (-3SD), or seven consecutive intensity values fall on the same side of the mean
intensity, an out-of control condition is signaled and a corrective action should be taken
following section 5.3.4 to correct the error.
其中Xm is the mean intensity value of the control point standard solution which is collected 20
times on different days就是其某个固定浓度强度平均值是其连续20天测试值的平均值（至少20个数据）

我们现在主要就是有日常QC偏差来对仪器强度进行管控，主要是质控样做控制图来监控整个方法的

原文由 砂锅粥(czcht) 发表:貌似仪器的强度不需要监控啊，因为你换了矩管或者换了雾化器强度就会变化。是否监控QC含量更合理？如果要监控我觉得监控矩管准直Mn之类的元素强度是否更好？

我也是这样想的，直接监控QC更好，因为有固定值。如果监控Mn强度，这也是个浮动值。

我们是采用固定方法中的标准曲线斜率通过趋势图加以管控

原文由 JOE HUI(xurunjiao5339) 发表:早期做美泰玩具测试时候其内部标准GL0P7409《 ICP MAINTENANCE AND PERFORMANCE CHECKS》就有这样提到5.3 Daily Performance CheckThe daily performance of the ICP machine shall be monitored by measuring the intensity value ofthe control point standard solution and evaluating any trending per the charting proceduresstated below:5.3.1 The Intensity Trend Chart is obtained by plotting the intensity value against the runnumber on a line graph. Choose a concentration value that is used in the calibrationprocedure (i.e. 0.05, 0.1 or 0.5 ppm for lead) when creating the Trend Chart (refers to?5.4.1.3 for the updated calibration points). The intensity values shown below werederived from middle range of standards in 20% nitric acid. 20 different readings from 20different days should be recorded and graphed (see Figure 1).X is the intensity value of the control point standard solution (middle range standardsolution of each element),Xm is the mean intensity value of the control point standard solution which is collected 20times on different days,SD is the standard deviation of 20 measurements,UCL is upper control limit, UCL=Xm      3SD; LCL is lower control limit, LCL=Xm-3SD; UWLis upper warning limit, UWL=Xm 2SD; LWL is lower warning limit, LWL= Xm-2SD.5.3.2 Daily ICP intensity for each element should be tested and reported on the ICP dailyintensity chart. An example of the ICP intensity chart is attached in Addendum 1.Intensity trend chart should be reviewed every 6 months.5.3.3 If two consecutive intensity values fall in the acceptance criteria area    2SD (-2SD) & 3SD (-3SD), or seven consecutive intensity values fall on the same side of the meanintensity, an out-of control condition is signaled and a corrective action should be takenfollowing section 5.3.4 to correct the error.其中Xm is the mean intensity value of the control point standard solution which is collected 20times on different days就是其某个固定浓度强度平均值是其连续20天测试值的平均值（至少20个数据）

这个平均值就有一定浮动性了，除非你能保持长期稳定这个值。而实际上在更换矩管等操作后，强度值会有一定程度变化，所以我觉得这个管控好像并不合理。

原文由 卍字不是字(Ins_0d32abf1) 发表:这个平均值就有一定浮动性了，除非你能保持长期稳定这个值。而实际上在更换矩管等操作后，强度值会有一定程度变化，所以我觉得这个管控好像并不合理。

只要仪器没有经过大修，其均值应该在一个范围内，这样也是合理的

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咨询工程师

你说的是期间核查，这需要按照程序文件进行，一般是用特征指标的特征浓度去做，选择曲线中间点是可以的。