Correction factor derivation

Data from Meylan and Howard (1995) total number of correction factors derived 235. b o = ortho, m = meta,p = para substitution.c See Illustrative Example 7.2. 

Fc = semi empirical polarity correction factor derived for several classes of compounds (i.e., acetanilides = 0.31 amides = 0.66 halogenated aromatic hydrocarbons = -0.20 non-halogenated aromatic hydrocarbons = -0.27 carbamates = 0.27 dinitroanilines = 0.19 organophosphorous pesticides = 0.01 PAHs = -0.93, triazines = 0.24, triazoles = -0.22 ureas = 0.19). 

The effect of surface charge on sorption (extent of complex formation) can be taken into account by applying a correction factor derived from the electric double-layer theory to the mass law constants for surface reactions. 

For balanced valves a correction factor derived from Figure 6-12 (or from the manufacturer s data) must be applied if the back pressure, P2, is higher than 0.5 Pi psia. For unbalanced valves, the maximum allowable back pressure is usually 1/10 of the valve set pressure, in psig. 

Rabinowitsch correction n. The correction factor derived by Rabinowitsch (1929) applied to the Newtonian shear rate at the wall of a circular tube (including capillary) through which a non-Newtonian liquid is flowing, gives the true shear rate at the wall. For pseudoplastic liquids such as paints and some polymer melts the correction is always an increase. If the fluid obeys the power law it reduces to a simple correction factor (3n+ l)/4n, where n is the flow-behavior index of the liquid. Munson BR, Young DF, Okiishi TH (2005) Fundamentals of fluid mechanics. John Wiley and Sons, New York. Harper CA (ed) (2002) Handbook of plastics, elastomers and composites, 4th edn. McGraw-Hill, New York. 

Using correction factors derived from efficiency calibration curves... 

If scanning electrostatically, by using correction factors derived from analysis of a substance of known isotopic composition, e.g. Dietz et al. (1962). 

The rate of chemical diffusion in a nonfiowing medium can be predicted. This is usually done with an equation, derived from the diffusion equation, that incorporates an empirical correction parameter. These correction factors are often based on molar volume. Molecular dynamics simulations can also be used. 

Another principal difficulty is that the precise effect of local dynamics on the NOE intensity cannot be determined from the data. The dynamic correction factor [85] describes the ratio of the effects of distance and angular fluctuations. Theoretical studies based on NOE intensities extracted from molecular dynamics trajectories [86,87] are helpful to understand the detailed relationship between NMR parameters and local dynamics and may lead to structure-dependent corrections. In an implicit way, an estimate of the dynamic correction factor has been used in an ensemble relaxation matrix refinement by including order parameters for proton-proton vectors derived from molecular dynamics calculations [72]. One remaining challenge is to incorporate data describing the local dynamics of the molecule directly into the refinement, in such a way that an order parameter calculated from the calculated ensemble is similar to the measured order parameter. 

These correction factors are given in various heat transfer te.xts. In lieu of correction factor curves use the following procedure to derive the factor ... 

The pressure controller (controller block) amplifies the transmitter signal and sends a modified signal to the final element. Depending on the system requirements, the controller block may include additional correction factors, integral and derivative (reset and rate). This is called a three-mode controller. 

If the mobile phase is a liquid, and can be considered incompressible, then the volume of the mobile phase eluted from the column, between the injection and the peak maximum, can be easily obtained from the product of the flow rate and the retention time. For more precise measurements, the volume of eluent can be directly measured volumetrically by means of a burette or other suitable volume measuring vessel that is placed at the end of the column. If the mobile phase is compressible, however, the volume of mobile phase that passes through the column, measured at the exit, will no longer represent the true retention volume, as the volume flow will increase continuously along the column as the pressure falls. This problem was solved by James and Martin [3], who derived a correction factor that allowed the actual retention volume to be calculated from the retention volume measured at the column outlet at atmospheric pressure, and a function of the inlet/outlet pressure ratio. This correction factor can be derived as follows. 

It is now necessary to derive an expression for (Pr) and then the correction factor —... 

A slit die is designed on the assumption that the material is Newtonian, using apparent viscous properties derived from capillary rheometer measurements, at a particular wall shear stress, to calculate the volumetric flow rate through the slit for the same wall shear stress. Using the correction factors already derived, obtain an expression for the error involved in this procedure due to the melt being non-Newtonian. Also obtain an expression for the error in pressure drop calculated on the same basis. What is the magnitude of the error in each case for a typical power law index n = 0.377... 

Derivations based on the introduction of this modified equation lead to a small correction factor within the Ilkovic equation, viz.,... 

The following assumptions are made in the derivation of the temperature correction factor F in addition to those made for the calculation of the log mean temperature difference ... 

The relativistic derivation of the relationship between the Compton cross section and the Compton profile leads to a further correction factor [7]. Finally a background subtraction and a normalization of the valence profiles to the number of valence... 

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