Standard Operating Conditions - Lab Report Example

There is no major change when the instrument is operated at different view heights. [Refer to Table 1- 4]. Since the weights are not mentioned. It should be noted that the normal calibration curve without Yttrium gives good results as compared to the one with I.S. Proof being that with yttrium I.S the responses are suppressed and hence lower values in table 4. Especially for LFHIx 0.5, 1 and 2. Table 3 gives the correct readings against lower values in table

In changing from radial to axial mode there is an average increase in responses by 2 - 4 times. In the case of P [at a wavelength of 178.221] and K, the average increase is 26 and 36 times in changing from radial to axial modes of measurement. [Table -5]

The compounds which should be measured in the axial modes are P [at a wavelength of 178.221], S, Zn, and Fe. For S there is a good increase of 13 times in shifting from radial to axial modes. [Table -5]

1. How did the background signal and S/B ratios vary when operating conditions were changed? Select any three elements to evaluate in your answer.

Ans: There is no change in normal operating conditions. And there was no change observed when using increased RF power as well. A good reduction of S/B was observed when operating with high nebulizer flow rates eg: for compounds like Mg, Cr, and P [at a wavelength of 213.617]. Approximately 10.9 – 11.1 time reduction in the S/B ratios when operated in axial modes with increased nebulizer flow from 0.40 – 1.00 L/min. There is no major change when the instrument is operated at different view heights.  [Refer to Table 1- 4].

2. Present the analytical data obtained for the multielement analysis of the ASPAC samples

Table 1: Analytical data for Fe samples.

Note: The exact mass of samples used is not known.

3. Plot two calibrations for Fe, one using the Yttrium standard and another using Fe data only.

Graph 1: Fe 238 Axial Standard Curve

Graph 2: Fe 238 Axial Standard Curve using yttrium internal standard

6. Using residual plots to compare the linear fit for Fe calibration, with and without Yttrium I.S

Ans: Refer to Graphs 1 and 2. Both graphs have a linear fit.

7. Present the analytical results for Fe, from each of the calibration procedures used. Comment on any difference between the results and their significance.

Ans:

Table 3: Results from Fe calibration curve without Yttrium I.S

Table 4: Results from Fe calibration curve with  Yttrium I.S