Accuracy evaluation manual methods

A flow injection method based on the catalytic action of iodide on the colour-fading reaction of the FeSCN2+ complex was proposed and applied in order to determine iodine in milk. At pH 5.0, temperature 32°C and measurements at 460 nm, the decrease in absorbancy of Fe -SCN (0.10 and 0.0020 mol /I) in the presence of N02" (0.3 mol/ 1) is proportional to the concentration of iodide, with a linear response up to 100.0 pg/1. The detection limit was determined as 0.99 pg/1 and the system handles 48 samples per hour. Organic matter was destroyed by means of a dry procedure carried out under alkaline conditions. Alternatively, the use of a Schoninger combustion after the milk dehydration was evaluated. The residue was taken up in 0.12 mol/1 KOH solubilization. For typical samples, recoveries varied from 94.5 to 105%, based on the amounts of both organic matter destroyed. The accuracy of the method was established by using a certified reference material (IAEA A-11, milk powder) and a manual method. The proposed flow injection method is now applied as an indicator of milk quality on the Brazilian market (de Araujo Nogueira et al., 1998). 

The clustering analysis is another mean to find and evaluate structures in seismic clouds. Phillips et al, (1997) and Phillips (2000) proposed a repicking method, which produces the relative time difference of phases within a group of similar microseismic events, followed by master event relative source locations. For this analysis, waveforms are lined up after low pass filtering, with P- and S-wave arrival times are manually repicked from a similar portion of the waveform. The technique can be used to identify wave arrival times and improve the accuracy of relative source location determinations. Phillips (2000) applied this analysis to microseismic clouds created by hydraulic stimulation in the Soultz HDR reservoir and delineated two distinct intersecting planar structures. 

Currently informatization of safety quality standardization evaluation work is at low level. Quality evaluation management is characterized by the traditional manual approach. Based on a cloud management platform and mobile terminal can be digitized in management of evaluation content. After input assessment data, the system will automatically generate related evaluation results and statistical information with print function. The system also can be added to the policy query and evaluation method study module at the same time, convenient query management personnel evaluation, improving the efficiency and accuracy of the work. 

Dilution of Buffer. Precision and accuracy of the dilution by the Apricot personal pipettor for aqueous buffer were also evaluated using the same dye. The original samples at four different concentrations, 0.125,0.167,0.25, and 0.5 mM, were diluted 10-fold and 100-fold by both 12-channel pipettor and the Apricot personal pipettor. These results show that the Apricot pipettor picked up 90% to 99% of the amount picked up by the manual pipettor. The %RSD (n = 4), which is the precision of the dilutions, varied between 2% and 9%. A reasonably good correlation between these two methods at the four levels of concentrations is shown in Figure 17.3B. 

Figure 28 compares various practical curves and the methods for their manual interpretation. Such current - voltage curves, and others, can be evaluated more rapidly and with improved accuracy with computer-controlled instruments. The best values are obtained when a polynomial describing the approximate shape of the baseline is used. The coefficients of the polynomial are determined from the experimental jxrints which lie on both sides of the current peak [4). 

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