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Logarithms, table INDEX

Table 11.7 Molecular properties of some steroids. EEL represents the efficacy index of steroids as an endermic liniment, and CIBV represents the logarithmic contraction index of blood vessels. Reproduced by permission of World Scientific, ref. 25. Table 11.7 Molecular properties of some steroids. EEL represents the efficacy index of steroids as an endermic liniment, and CIBV represents the logarithmic contraction index of blood vessels. Reproduced by permission of World Scientific, ref. 25.
TABLE 1 Logarithm of refractive index for cyclohexanone-tetrachloroethane mixtures... [Pg.211]

Surfactant surface activity is most completely presented in the form of the Gibbs adsorption isotherm, the plot of solution surface tension versus the logarithm of surfactant concentration. For many pure surfactants, the critical micelle concentration (CMC) defines the limit above which surface tension does not change with concentration, because at this stage, the surface is saturated with surfactant molecules. The CMC is a measure of surfactant efficiency, and the surface tension at or above the CMC (the low-surface-tension plateau) is an index of surfactant effectiveness (Table XIII). A surfactant concentration of 1% was chosen where possible from these various dissimilar studies to ensure a surface tension value above the CMC. Surfactants with hydrophobes based on methylsiloxanes can achieve a low surface tension plateau for aqueous solutions of —21-22 mN/m. There is ample confirmation of this fact in the literature (86, 87). [Pg.730]

For NPTLC, the solvent strength weighting factor 5, is j the same as the polarity index F given in Table 1. The polarity index P is given by the sum of the logarithms of the polar distribution constants for ethanol, dioxane, and nitromethane, and the selectivity parameters x, is given as the ratio of polar distribution constant for solute I to the... [Pg.615]

For this study, we selected 42 representative FGs from a list of more than 500 substituents compiled by Hansch et a/.128 The electrophilicity index co for the whole series of ethylene derivatives, together with the experimental electronic substituent effects from the reactivity index co was as follows we first compared the computed co values with the experimental crp (see Figure 8). The analysis revealed a poor linear correlation between both quantities, with a regression coefficient R2 = 0.53. A better correlation was found when all the 42 points were fitted to a logarithm curve (.R2 = 0.84, see Figure 8). [Pg.183]

IAP < Ksp, Ar/x < 0, and calcite will dissolve. The quantity (aCa2+ aco2-) in a real solution is called, appropriately enough, the Ion Activity Product (IAP) for calcite, and similarly for any other solubility product reaction. The AP/Ksp ratio is called 2, and the logarithm of the ratio is called the Saturation Index (SI), so that when SI > 0 the mineral precipitates, and when SI < 0 the mineral dissolves (Table 3.2). [Pg.45]

Table 2 is based on qualitative estimates of occupational morbidity index (Izmerov Denisov, 2003) at logarithmic scale with its values from 0 to 1. The borderline between classes 3.4-4 relatively to classes 1-2 corresponds to following risk values a) somatic diseases and mutagenic disorders - RR>5 b) ageing acceleration - 10 years or more c) work-related mortality - standardized relative risk SRR>7. These indices characterize different sides of health and quality of life, including risk for off-spring health. [Pg.143]

Matching to Tables 15.1 and 15.2 the saturation indices are demonstrated in Table 15.3, likewise calculated by applying the PHREEQC model (Parkhurst 1995 Parkhurst and Appelo 1999). Here, the majority of the saturation indices have been calculated on the basis of mineral phases, however, there are also gaseous phases denoted as COj(g) , Hj(g) , NHjlg) , O Cg) . The saturation index stands for the common logarithm of the respective partial pressure. The number of minerals and gases listed in Table 15.3 depends on the fact that calculations can only be performed after all the ions involved have been analyzed, and furthermore, provided that the database file of the program contains the appropriate thermodynamic data. [Pg.517]

Table 15.3 According to the species distribution shown in Table 15.2, the PHREEQC model (Parkhurst 1995) was also applied to calculate the saturation indices. Here, CO2 (g), H2(g), NHjtg), OjCg) do not stand for mineral phases, but for gaseous phases in which the saturation index is obtained as the logarithm of the respective partial pressure. Table 15.3 According to the species distribution shown in Table 15.2, the PHREEQC model (Parkhurst 1995) was also applied to calculate the saturation indices. Here, CO2 (g), H2(g), NHjtg), OjCg) do not stand for mineral phases, but for gaseous phases in which the saturation index is obtained as the logarithm of the respective partial pressure.
To further characterize the selectivity of carbene CXY, we can compare its discrimination between the olefins of the standard set with that of CCI2, which we designate the standard carbene. We plot the logarithms of the relative reactivities for CXY against analogous data for CCI2 (with the relative reactivities all adjusted to the standard alkene, isobutene, = 1.00), and then determine the slope of the correlation line, Wcxy- We call m xy the carbene selectivity index, defined as the least-squares slope of log (V o)cxy s. log (kJk QQX. [8,9,16,17] The m xv values for the carbenes of Table 1, determined in this manner, are m p = 1.48 mcci, 1-00 (by definition), and m Br, 0-65. [Pg.60]

Table 5.3. Correlation between the logarithm of the proline concentration and the ripeness index in two Champagne ... Table 5.3. Correlation between the logarithm of the proline concentration and the ripeness index in two Champagne ...
In addition to the similarity indices described above, other similarity indices may be defined and used in QSAR studies. A simple lipophilidty similarity index aij = — log Pi — log PjI (log Pi, logPj = logarithms of the partition coefficients of molecules i and j) can be applied to describe nonlinear lipophilicity-activity relationships of any type by the corresponding lipophilidty similarity matrices [1013]. For different data sets excellent results were obtained (Table 31), not only in homologous series (as in CoMFA studies [1025 — 1027]) but also in heterogeneous sets of compounds, where 3D QSAR approaches must fail. A selection procedure based on genetic algorithms was developed for fast and efficient variable elimination in the PLS analyses [1013]. Also in these examples the similarity matrices produced improved Tpress values in fewer components after elimination of variables which did not contribute to prediction (Table 31). [Pg.175]

Table 11.2 Stability constants (logarithmic) of some complexing agents (in water at 20°C) (saturated constants reported as log P). The ratio is given as a pre-index thus manganese forms a 2 1 complex with bipyridyl (log = 6), reported as 6 whereas it forms only a 1 1 complex with EDTA (log = 13), reported as 13... [Pg.457]

Of course natural solutions, such as seawater, are not necessarily at equilibrium. In Figure 16.2 we see a river carrying dissolved material, including calcium and carbonate ions, entering the sea. Carbonate ions are already there, because the sea is in contact with the atmosphere, which contains carbon dioxide, and when CO2 dissolves it produces carbonate and bicarbonate ions. Because calcium and carbonate are being added, there may be a tendency for them to increase beyond the equilibrium value, and for calcite to precipitate as a result. The product of the calcium and carbonate ion activities which are actually present in a solution, regardless of any theory, is called the ion activity product (lAP) for that solution. It follows that when lAP > K, calcite will precipitate, and when lAP < calcite will dissolve. The lAP/ Tsp ratio is called O, and the logarithm of the ratio is called the saturation index (SI), so that when SI > 0 calcite precipitates, and when SI < 0 calcite dissolves (Table 16.1). [Pg.476]

In order to identify the behavior of the suspension fluid, the data in Table 10.7 can be plotted to verify resemblance to the typical fluids represented in Figure 10.2. The parameters of characterization can be determined from a logarithmic plot, where n would represent the flow behavior index and the intercept of the line on the y-axis the fluid consistency index. Plotting data from Table 10.7, Figure 10.16 is obtained. [Pg.358]

As discussed in Section 5.2.5, Van Kolck et al. (2008) developed 4 QSARs to predict the 96-hour LC50 values of 5 cations to the mussel Mytilis edulis and 4 QSARs to predict the 96-hour LC50 values of 6 cations to the mussel Perna viridis (Table 5.17). Six of these QSARs included 3 of the less numerous physical properties used to predict cation toxicity, viz., covalent index (x r), absolute value of the logarithm of the first hydrolysis constant (Hog XqhI), and ionic index (Z /r). The QSARs developed with the covalent index (x r) produced the highest value (Table 5.20). [Pg.214]

As noted above, Mendes et al. (2010) developed QSARs for predicting cation toxicity using standard reduction-oxidation potential, electronegativity, and the Pearson and Mawby (1967) sofmess parameter (Table 5.12). However, Mendes et al. (2010) developed 9 QSARs for predicting cation toxicity using some less numerous physicochemical properties (Table 5.20). The QSARs developed with the covalent index (X r) or X t and the absolute value of the logarithm of the first hydrolysis constant (Hog /(qhI) had the highest revalues, lowest p values, and lowest AIC values (Table 5.20). [Pg.215]

Table 1. Logarithm of relative molecular weight log (l/Op)/ (s rad- )), standard deviation a, and polydispersity index PDI of the three pulps calculated by the rheology-based method with different concentrations. Table 1. Logarithm of relative molecular weight log (l/Op)/ (s rad- )), standard deviation a, and polydispersity index PDI of the three pulps calculated by the rheology-based method with different concentrations.
Table 3. Logarithm of molecular weight logMp, mass-average molecular weight Mw, number-average molecular weight Mn, and polydispersity index PDF of the three pulps measured by the GPC method. Table 3. Logarithm of molecular weight logMp, mass-average molecular weight Mw, number-average molecular weight Mn, and polydispersity index PDF of the three pulps measured by the GPC method.
The dose—response relationships for EP change with Pb exposure, including thresholds, are logarithmic and appear to show that children are more sensitive than adults, while women are somewhat more sensitive than men (Table 16.6). For children, the dose—response relationship persists down to a threshold in blood lead on the order of 15—20 xg/dl, and in adults across gender, 25—35 p-g/dl. The dose—response relationship of EP and PbB is affected by the time course of EP s accumulation with increase in Pb exposure indexed through PbB. [Pg.619]

FIGURE 8.4 Plot of logarithm of adjusted retention time versus Kovats index. TABLE 8.1 Pesticide Relative Retention Times... [Pg.410]

Table 2. Stiffness G modulus of polymer obtained at various temperatures. Seal-logarithmic regression as a function of the melt flow index -bulk hoaopolymerization process - 3 hours - cocatalyst mOBAC Units G modulus in daN/cm2 MFI in g/lOnin. Table 2. Stiffness G modulus of polymer obtained at various temperatures. Seal-logarithmic regression as a function of the melt flow index -bulk hoaopolymerization process - 3 hours - cocatalyst mOBAC Units G modulus in daN/cm2 MFI in g/lOnin.
The slope of this dependence is close to that of a similar plot obtained in the molten KCl-NaCl equimolar mixture. The increase of the metal oxide solubilities in the Ba -based melt as compared with the KCl-NaCl melt (see Table 9.2.14) demonstrates that the oxoacidic properties of Ba cation are considerably stronger than those of K or Na cations. It should be added that the value of the dissociation constant of BaO in the molten KCl-NaCl was determined " to be 81. The logarithm of the latter magnitude equals to 1.91 that is very close to 1.84 and to the oxobasicity index of the BaCl2-KCl-NaCl eutectic, which is 2.01 as it has been previously pointed out. [Pg.572]


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Logarithm tables

Logarithms

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