Nickel calibration curves

Figure 13 shows the calibration curve of phase-lag for the nickel foils of various thickness. This result suggests the possibility of estimating the thickness of plated materials on the metal. Figure 14 shows the PAXAS spectrum of nickel-plated copper. In the photoacoustic amplitude spectrum, EXAFS of copper at the subsurface of sample was still detected clearly. This means that PAXAS method can be applied... 

Fig. 13. Calibration curve of phase-tag for the heat wave propagation in nickel foil. Chopping frequency 27.6 Hz. See text for other experimental detail...

Copper, Chromium, Manganese, and Nickel. The analytical method for determining copper, chromium, manganese, and nickel involves digesting the coal with nitric and perchloric acids, fusing the residue with lithium metaborate, and determining the combined digestion and leach solutions by atomic absorption spectrophotometry. Since there is no standard material to analyze for the construction of calibration curves, the standard additions method is used for the assay. While this method increases the time required for analysis, it helps to eliminate the effect of the matrix. 

Conditioning of the manganese oxide suspension with each cation was conducted in a thermostatted cell (25° 0.05°C.) described previously (13). Analyses of residual lithium, potassium, sodium, calcium, and barium were obtained by standard flame photometry techniques on a Beckman DU-2 spectrophotometer with flame attachment. Analyses of copper, nickel, and cobalt were conducted on a Sargent Model XR recording polarograph. Samples for analysis were removed upon equilibration of the system, the solid centrifuged off and analytical concentrations determined from calibration curves. In contrast to Morgan and Stumm (10) who report fairly rapid equilibration, final attainment of equilibrium at constant pH, for example, upon addition of metal ions was often very slow, in some cases of the order of several hours. 

Figure 1. The effect of the acetylene-to-air ratio on the calibration curve of nickel. Curve 1 was obtained with a fuel-rich fame stoichiometry Curves 2 and 3 were obtained with progressively less fuel-rich flame stoichiometries. All experiments were performed with single analyte solution in 10% HNOa.

Carbon contaminated surfaces were prepared by thermally decomposing benzene on the nickel surface. The carbon overlayer was ordered but the diffraction pattern was complex. It did not correspond to a graphitic ring structure. Approximate carbon coverages were estimated using Auger calibration curves based on thermally decomposed benzene (10). 

Two x-ray fluorescence spectrometers were used for the analyses a General Electric XRD-6 for iron, copper, tin, and antimony, and a General Electric XRD-5 for nickel, silver, and lead (the latter machine has updated electronics and gave superior results for these three elements). Four certified standards from the National Bureau of Standards were used for each element to obtain a straight line calibration curve using linear regression (10). The experimental conditions used for the determination of each element were given by Carter et al. (10). 

Another effect of reducing the quantity of APCD added is that the effect of EDTA on the calibration curve slope is magnified. Comparison of Table III with Table II shows that the effect of 100 ppm EDTA on the calibration curve slopes for zinc and nickel is much more pronounced if only 20 mg APCD is added instead of 200 mg. If one assumes a simple competition between EDTA and pyrrohdinecarbodithioate, this behavior is not at all surprising. 

Although increasing the quantity of APCD added in the extraction changed the slope of the calibration curves but little, it had a profound effect on the calculated concentration of nickel, lead, and cadmium. In Figure 5a, a definite increase is observed in the concentration of cadmium, lead, and nickel as the quantity of 5% APCD added per 800 ml was increased beyond approximately I ml. Figure 5b presents the results for copper and zinc. Copper is unaffected by the quantity of APCD added. The case for zinc is less clear, no doubt because of the decrease in calibration curve slope and the resulting decrease in precision as the quantity of APCD is reduced below 1 ml per 800 ml of sample. The... 

Figure 32. Amperometric response of rotating Cat/NiO modified GC electrode to H202, conditions -0.3 V constant potential, pH 7.0 and rotation speed is 2000 rpm, (A) successive addition of lOOpM and (B ) 1 liM insets plot of chronoamperometric current vs, H202 concentration and linear calibration curve for determination of KM. Reprinted from Biophysical Chemistry, 125, A.Salimi, E. Sharifi, A. NoorBakhash, S. Soltanian, Direct electrochemistry and electrocatalytic activity of catalase immobilized onto electrodeposited nano-scale islands of nickel-oxide, 546, Copyright( 2007), with permission from Elsevier.

Fig. 7-11 Calibration curve of a multichamber Geiger counter. Cu Ka radiation. Nickel foils, each 0.01 mm thick, used as absorbers.

We are not able to explain the value of 0.05 ppm for nickel except to say that the data points of the calibration curve from which the value was derived were much more irregular than was the case for the 0.40 and 0.48 values. 

Read off the appropriate nickel content from the calibration curve on the basis of the measured extinction, take into account the quantity of water used and the blank reading, and recalculate for 1 litre of water. 

Figure 5 illustrates temperature calibration curves for both DTA/DSC and TGA using high piuity nickel as a magnetic material (Curie point = 358.4°C). Unlike Tm, the Ciude point temperature is practically unaffected by the changing of the heating rate between 1 to 20°C/min. 

Figure 8.46 Calibration curves for nickel in oil, obtained simultaneously using the absorption lines at 232.003 nm and 232.137 nm, shown in Figure 8.45...

Calibration Curve - The absorbance (A) is plot versus mg/L nickel in the standard series. 

Standard solution (containing tin or titanium for barium and calcium, zirconium for phosphorus, and nickel for zinc) is poured into an X-ray cell. Total net counts (peak intensity— background) for each element and its respective internal standard are collected at their appropriate wavelengths. The ratios between elemental and internal standard counts are calculated and converted into barium, calcium, phosphorus, or zinc concentrations, or a combination thereof, from calibration curves. 

The moderator temperature was obtained from the net resistance of the nickel wire. A calibration curve of temperature versus the resistance of the nickel wire had previously been made with the same nickel wire interconnecting the six individual elements as when mounted in the reactor. 

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