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Numerical logarithmic

The logarithm of a quotient is equal to the logarithm of the numerator minus the logarithm of the denominator thus,... [Pg.176]

The multiple use of logarithms in the analysis presented by Fig. 4.9 obliterates much of the deviation between theory and experiment. More stringent tests can be performed by other numerical methods. [Pg.234]

Catalyst Cation. The logarithms of extraction constants for symmetrical tetra- -alkylammonium salts (log rise by ca 0.54 per added C atom. Although absolute numerical values for extraction coefficients are vastly different in various solvents and for various anions, this relation holds as a first approximation for most solvent—water combinations tested and for many anions. It is important to note, however, that the lipophilicity of phenyl and benzyl groups carrying ammonium salts is much lower than the number of C atoms might suggest. Benzyl is extracted between / -propyl and -butyl. The extraction constants of tetra- -butylammonium salts are about 140 times larger than the constants for tetra- -propylammonium salts of the same anion in the same solvent—water system. [Pg.187]

Usually, diffusivity and kinematic viscosity are given properties of the feed. Geometiy in an experiment is fixed, thus d and averaged I are constant. Even if values vary somewhat, their presence in the equations as factors with fractional exponents dampens their numerical change. For a continuous steady-state experiment, and even for a batch experiment over a short time, a very useful equation comes from taking the logarithm of either Eq. (22-86) or (22-89) then the partial derivative ... [Pg.2040]

Fig. 27. Logarithm of normalized rate constant ln(fc/nto) versus dimensionless coupling strength C /Q for PES (4.28) with Q = 0.1, n = 1, F /a>o = 3. Separate points and dashed line correspond to instanton result and numerical data [Hontscha et al. 1990]. Fig. 27. Logarithm of normalized rate constant ln(fc/nto) versus dimensionless coupling strength C /Q for PES (4.28) with Q = 0.1, n = 1, F /a>o = 3. Separate points and dashed line correspond to instanton result and numerical data [Hontscha et al. 1990].
The logarithm of a positive number N is the power to which the base (10 or e) must be raised to produce N. So, x = log N means that e = N, and x = log,(,N means that lO = N. Logarithms to the base 10, frequently used in numerical computation, are called common or denary logarithms, and those to base e, used in theoretical work, are called natural logarithms and frequently notated as In. In either case,... [Pg.21]

The conductivity of a solution containing such molecular ions may be small compared with the value that would result from complete dissociation into atomic ions. In this way, in the absence of neutral molecules, we can have a weak electrolyte. The association constant for (29) has a value that is, of course, the reciprocal of the dissociation constant for the molecular ion (PbCl)+ the logarithms of the two equilibrium constants have the same numerical value, but opposite sign. [Pg.39]

A great deal of attention has been paid to the question of the necessity of having logarithmic terms in the expansion (Gronwall 1937, Bartlett 1952, 1955, Fock 1954, Hylleraas 1955), but Kino-shita has pointed out that although such terms may be convenient from the. numerical point of view (Hylleraas and Midtdal 1956), they are not necessarily required by the form of the Schrodinger equation itself. [Pg.298]

The first treatment is clearly inferior, lacking appropriate weights. The second is preferred. The logarithmic function is insensitive to weighting, because the spread of the numerical values of log(k/T) is narrow. [Pg.40]

Determination of the model parameters in Equation (7.7) usually requires numerical minimization of the sum-of-squares, but an analytical solution is possible when the model is a linear function of the independent variables. Take the logarithm of Equation (7.4) to obtain... [Pg.255]

Error bars defined by the confidence limits CL(y,) will shrink or expand, most likely in an asymmetric manner. Since we here presuppose near absence of error from the abscissa values, this point applies only to y-transformations. A numerical example is 17 1 ( 5.9%, symmetric CL), upon logarithmic transformation becomes 1.23045 -0.02633. .. 1.23045 + 0.02482. [Pg.129]

Thus, when the associated (protonated) and dissociated (conjugate base) species are present at equal concentrations, the prevailing hydrogen ion concentration [H+] is numerically equal to the dissociation constant, A. If the logarithms of both sides of the above equation are... [Pg.10]

Similarly to RPLC, there is a strong Unear correlation between the logarithm of the retention factor measured by MEKC (logfe) for neutral solutes or the neutral form of ionizable compounds and log P supplementary material (see Sechon 13.5), numerous papers reported good correlations between log Pod and log k. [Pg.348]

At current densities well below the limiting value, j can be neglected against yd in the numerator of the expression after the logarithm in Eq. (5.4.26) rearrangement then yields... [Pg.298]

In contrast to the weights formalism, the partition function approach directly employs the ideal flat-histogram expression in (3.36). Its goal is not to determine q but Q(N. V, T) directly, or more precisely in this case, the N dependence of Q. Due to numerical reasons, we usually work instead with the associated thermodynamic potential which is the logarithm of the partition function of interest in this case it is In Q = — 7/1 =. A, where we have used script i as an abbreviation. Thus our sampling scheme becomes... [Pg.95]

This procedure has been used successfully to determine the composition of many complexes in solution. It is possible to extend this method to cases where more than one complex is formed but the application is quite difficult. Like the logarithmic method, Job s method can be applied to other cases of molecular interaction and is not limited to the formation of coordination compounds. Both methods are based on the assumption that one complex is dominant in the equilibrium mixture. Numerous other methods for determining the number of metal ions and ligands in complexes have been devised, but they are beyond the introduction to the topic presented here. [Pg.675]

From equation 2.2-10 and differentiation of the cA(f) data (numerically or graphically), values of (—rA) can be generated as a function of cA. Then, on taking logarithms in equation 3.4-1, we have... [Pg.49]

Using our calculators, we need to type ln(0.5093) as the numerator rather than a percentage. The minus sign comes from the laws of logarithms. [Pg.386]

D—The addition of zinc ion, from the ZnS( )4, increases the zinc concentration. This increases the numerator in the logarithm part of the Nernst equation. This is a negative term, so the cell voltage will decrease. [Pg.253]


See other pages where Numerical logarithmic is mentioned: [Pg.115]    [Pg.260]    [Pg.1183]    [Pg.431]    [Pg.770]    [Pg.75]    [Pg.1232]    [Pg.203]    [Pg.17]    [Pg.373]    [Pg.201]    [Pg.81]    [Pg.114]    [Pg.136]    [Pg.160]    [Pg.1214]    [Pg.39]    [Pg.98]    [Pg.37]    [Pg.112]    [Pg.288]    [Pg.167]    [Pg.452]    [Pg.71]    [Pg.64]    [Pg.337]    [Pg.343]    [Pg.175]    [Pg.250]    [Pg.79]    [Pg.257]   
See also in sourсe #XX -- [ Pg.382 ]




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Logarithms

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