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Mathematical correction equations

Mathematical correction procedures can be used to remove the contribution of a spectral overlap from a measured signal. However, if the signal due to the spectral overlap is much larger than the analyte signal, the signal-to-noise ratio of the corrected signal may be poor. Furthermore, it may not be easy to predict and account for quantitatively all of the potential sources of spectral overlap, particularly those due to polyatomic ions. For isobaric overlaps (Table 3.2), for which the relative isotopic abundances are predictable, mathematical corrections are straightforward. Instrument software often has built-in correction equations for this case. [Pg.109]

In arsenic assays, one possible way to eliminate interference resulting from the isobaric ions referred to above is application of correction equations. The contribution of argon chloride to the value of the signal measured for the As ion can be calculated because chlorine occurs as two isotopes, Cl and Cl. The latter forms the " Ar CE ion in plasma (signal at w/z 77). The intensity of the signal makes it possible to assess the necessary correction of ion signal intensity at w/z 75 by applying an appropriate mathematical equation [24, 62]. The approach is only possible if the ratio between the As and Cl content in the sample does not exceed... [Pg.341]

Solving a quadratic equation always yields two roots. One root (the answer) has physical meaning. The other root, while mathematically correct, is extraneous that is, it has no physical meaning. The value of x is defined as the number of moles of A per liter that react and the number of moles of B per liter that react. No more B can be consumed than was initially present (0.100 M), so x = 0.309 is the extraneous root. Thus, x = 0.099 is the root that has physical meaning, and the extraneous root is 0.309. The equilibrium concentrations are... [Pg.720]

This formula gives two roots, both of which are mathematically correct. A foolproof way to determine which root of the equation has physical meaning is to substimte the value of the variable into the expressions for the equilibrium concentrations. For the extraneous root, one or more of these substimtions will lead to a negative concentration, which is physically impossible (there cannot be less than none of a substance present ). The correct root will give all positive concentrations. In Example 17-7, substitution of the extraneous root x = 0.309 would give [A] = (0.300 — 0.309) M = —0.009 M and [B] = (0.100 — 0.309) M = —0.209 M. Either of these concentration values is impossible, so we would know that 0.309 is an extraneous root. bu should apply this check to subsequent calculations that involve solving a quadratic equation. [Pg.720]

Investigators have attempted to devise mathematical models to predict the phase behavior of compounds in CO2 by means of solute chemical structure alone. Equations of state often fall short of accurate prediction owing to lack of experimentally determined quantities (such as vapor pressure) and other physicochemical properties of the solute (50). Ashour et al., for example, surmised that no single cubic equation of state exists that is appropriate for the prediction of solubility in all supercritical fluid mixtures (51). To further complicate the issue, more than 40 different forms of equations of state and 15 different types of mixing rules have been evaluated vis-a-vis phase behavior in carbon dioxide (52) choosing the correct equation to model solubility in CO2 for a specific system can be a challenging undertaking. [Pg.12]

There are two solutions to the equation. Often you will be able to decide that one solution is mathematically correct but physically imposable. You may be calcubiing some physical quantity that cannot possibly be negative so that you will ignore a negative solution and adopt a positive solution. [Pg.21]

Alternatively, making adjustments to the dose rather than the toxicity values is just as acceptable and mathematically correct as using the following equation ... [Pg.131]

As shown before (Vermeil, 1917) equation (6.4), with cosmological constant, is the mathematically correct form of the gravitational field equations. [Pg.214]

On the basis of the results obtained, one can say that the SEFS results are very useful in analyzing the atomic structure of superthin surface layers of matter. But whenever studies of the local atomic structure can be performed by other methods, for example by EELFS, the complexity of the SEFS technique becomes an important disadvantage. However, in the experimental study of atomic PCF s of surface layers of multicomponent atomic systems within the formalism of the inverse problem solution, a complete set of integral equations is necessary to provide mathematical correctness. This set of equations can be solved by the methods of direct solution only. In this case the use of the SEFS method may be a necessary condition for obtaining a reliable result. Besides, the calculations made can be used as a test when studying multicomponent systems. [Pg.263]

The only mathematically correct way to report duration for a mixed portfolio of nominals and linkers, in a way that adds some useful information, is to drop the standard duration figure and instead show two new numbers duration with respect to real yield and duration with respect to inflationary expectations. These are the two main partial derivatives of the Fisher equation. [Pg.265]

The first of these is the sensitivity. This expresses the minimum detectable concentration (often as a function of range) and is usually quoted in the absence of interference. It is defined mathematically by equating the product aC with the noise level of the system. It is usually stated in units of path-integrated concentration, most correctly in units of pgm , or alternatively in ppm m (where ppm is used to express the partial pressure of the target species as millionths of the total atmospheric pressure). [Pg.4239]

As a final comment, the importance interpretation of the adjoint function may be used to write the adjoint equation by similar physical reasoning as is used to write the equation for the neutron density n. Thus the importance of a particular neutron is the same as the total importance of the neutron distribution that results from the original neutron at any later stage in the neutron cycle. Stating this relation in mathematical form results in a correct equation for the adjoint function m. [Pg.245]

The ohmic potential drop A0q often poses a practical limit to the precision of potential measurements. The use of an appropriate Luggin capillary helps to reduce its effect. In some cases one may mathematically correct for A0q using equation 4.9 or using a measured value. In Section 5.2 experimental methods will be presented that permit to experimentally determine A0q for any electrode arrangement. [Pg.124]

Nine different equations-of-state, EOS theories are described including Flory Orwoll Vrij (FOV) Prigogine Square Well cell model, and the Sanchez Lacombe free volume theory. When the mathematical complexity of the EOS theories increases it is prudent to watch for spurious results such as negative pressure and negative volume expansivity. Although mathematically correct these have little physical meaning in polymer science. The large molecule effects are explicitly accounted for by the lattice fluid EOS theories. The current textbooks on thermodynamics discuss... [Pg.359]

It should be clearly emphasized that the correct interpretation of experimental adsorption isotherms should be realized in terms of mathematical adsorption equations, i.e., in terms of adsorption isotherms. As mentioned in Introduction such equations are derived in close connection with the assumptions concerning a physical model of adsorption system. Such a model should include basic... [Pg.11]

Here P is expressed in atmospheres. The CO2 dissolves first to form hydrated molecules, which then slowly rearrange bonds to give carbonic acid molecules. However, as usual, we can be mathematically correct in using an equilibrium constant which relates only the initial and final species as done in Kp [see equation (10-5e)]. [Pg.187]

To solve the differential equation system and fit the parameters, Wachsen et al. [11] used two mathematical methods the Galerkin h-p method and a stochastic simulation method. On the other hand, in the cases where weight loss has occurred, other corrected equations for the simple random degradation have also been proposed by Yoon et al. [15]... [Pg.402]


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See also in sourсe #XX -- [ Pg.128 , Pg.129 ]




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Correction equations

Mathematical equations

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