Response factor equations

Where SA R is the specific area of the reference peak, and SA is the specific area of component x. AR is the GC peak area of the reference, Ax is the GC peak area of component x, WR is the weight of the reference, and Wx is the weight of component x. The weight percent of component x can be obtained from the sample chromatogram by using the relative response factors in the following equation ... 

Si is the laminar flame velocity, the function Z(co) is the heat response function Equation 5.1.16, whose real part is plotted in Figure 5.1.10. The function f(r, giJ is a dimensionless acoustic structure factor that depends only on the resonant frequency, a , the relative position, r, of the flame, and the density ratio Pb/Po-... 

Determine the response factors for the calibration curve analyses by the following equation ... 

Calculate an average value from the response factors obtained from the calibration curve analyses. Use the average response factor in the following equation to determine the residue levels in the sample ... 

The amount of tebuconazole residue (R) is calculated by applying the response factor (RF) to a standard (std) calibration curve. Calculations are performed using the instrument software using the following equation ... 

Calculate the response factor (RF) for a calibration standard in solvent using the equation... 

For the basic evaluation of a linear calibration line, several parameters can be used, such as the relative process standard deviation value (Vxc), the Mandel-test, the Xp value [28], the plot of response factor against concentration, the residual plot, or the analysis of variance (ANOVA). The lowest concentration that has been used for the calibration curve should not be less than the value of Xp (see Fig. 4). Vxo (in units of %) and Xp values of the linear regression line Y = a + bX can be calculated using the following equations [28] ... 

An internal standard can be used in two ways, usually depending upon the nature of the sample. In its simplest form the method uses the equation for calculating the response factor. A known constant amount of the internal standard is introduced into the sample and an aliquot of the mixture is injected. Knowing the concentration of the internal standard (Cs) and the response factor of the test substance (R) the concentration of the test compound is ... 

COMPARISON OF CAROTENOID COMPOSITION (juG/G) OF LEAFY VEGETABLES OBTAINED BY ONE-POINT CALIBRATION, STRAIGHT LINE EQUATION AND RESPONSE FACTORS... 

The discussion on ECN and relative mass response factors attaining equation 71 in Section V.B.7 applies also to quantitation of dialkyl peroxides, such as dicyclohexyl peroxide, cyclohexyl cycloheptyl peroxide and dicycloheptyl peroxide after separation by GLC-FID . ... 

Note that all the desired properties depend directly or Indirectly on the ratio A/n and therefore, on the relative response factors and signal to noise ratios of the spectrophotometer and the differential refractometer. In general, spectrophotometers are more sensitive than differential refractometers, therefore, the ratio A/n at the tails of the chromatogram, that is, the refractometer signal will be zero while there still be a signal from the spectrophotometer. In addition, equations 9 and 10 are hyperbolic functions of the concentration. Thus, as the concentration decreases the apparent values of Mw and [n] will increase, increasing the uncertainty in the estimates of the molecular weights and the intrinsic viscosities (see Appendix I and references 26-29). In the limit when A/n - (or n/A 0), the polymer... 

Response factor the response of drug substance or related substances per unit weight. Typically, the response factor of drug substance (or related substance) can be calculated by the following equation ... 

Relative response factor the ratio of the response factor of individual related substance to that of a drug substance to correct for differences in the response of related substances and that of the drug substance. It can be determined using the following equation ... 

To calculate the response factor Kt of a compound t, it is essential, according to equation (4.7), to know the injected quantity. However, it is difficult to know precisely the injected volume, which depends on the injector or injection loop or the precision of the syringe. Moreover, the absolute response factor K, (not to be confused with the partition coefficient) depends on the tuning of the chromatograph. This factor is not an intrinsic property of the compound. This is why most chromatographic methods for quantitative analyses, whether they are pre-programmed into an integrating recorder or software, do not make use of the absolute response factor, Kj. 

Solution First use the standard mixture to find the response factor in Equation 5-11 ... 

Using the known response factor, we substitute back into Equation 5-11 to find the concentration of unknown in the mixture ... 

An internal standard is a known amount of a compound, different from analyte, that is added to the unknown. Signal from analyte is compared with signal from the internal standard to find out how much analyte is present. Internal standards are useful when the quantity of sample analyzed is not reproducible, when instrument response varies from run to run, or when sample losses occur in sample preparation. The response factor in Equation 5-11 is the relative response to analyte and standard. 

F. (a) Use the internal standard equation with X = Pb2+ and S = Cd2L From the standard mixture, we find the response factor, F ... 

H. (a) To find the response factor, we insert values from the first line of the table into the equation ... 

When signal is the peak height, the sample size is the mass flowrate through the detector at the peak maximum, for the mass flow sensitive detector. For the concentration-sensitive detector, the sample size is the concentration in the detector at the peak maximum. Table 5.3 gives the equations for response factor in terms of weight, M, of compound injected. 

TABLE 5.3 EQUATIONS FOR RESPONSE FACTOR IN TERMS OF WEIGHT (M) OF COMPOUND INJECTED, PEAK WIDTH (W), AND FLOW (F). 

Equations 29, 30, and 31 can be combined to yield an equation similar to Equation 31 relating the response factor R to the reciprocal of Mn... 

Take a 200-pl aliquot of labeled standard solution (A ) and 200 (ll of ester (E) in approximately the same concentration and determine the exact concentration of the labeled standard by peak area comparison correcting for the previously determined response factor according to the equation ... 

Calculate the response factor (RF) for each acid in the standard using the equation RF = CM, where C is the concentration (ppm) of the organic acid in the standard solution and A is the peak area generated (AU). 

Peak, area should be linearly proportional to analyte concentration (y = ax + b) with a correlation coefficient >0.98 and an intersect very near the origin. In this equation, y is the peak area, x is the concentration of standard solution, a is the response factor between peak area, and b is the concentration ( 0). 

Sensitivity is defined via the equation R = R0 + SC, where R is the detector output, S is the response factor or sensitivity, and C is the concentration (or mass flow rate if applicable). R0 is the response at zero concentration. It is obvious that when S is high, a slight change in concentration will produce a more detectable signal. 

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