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Some example calculations

Below are given some simple examples to illustrate the use of the above concepts in solving equilibrium speciation problems. To keep things relatively simple no [Pg.100]


A list of selected tau values for a range of different compounds can be found in Table 1. Some example calculations are presented below. [Pg.171]

Some example calculations demonstrating how to derive y,w and values from experimental solubility data are given in Illustrative Example 5.1. [Pg.139]

Hence, this approach is very similar to the one used for describing the effect of salt on aqueous solubility and aqueous activity coefficient (Eqs. 5-27 and 5-28). Some example calculations using Eq. 5-30 or 5-31, respectively, are given in Illustrative Example 5.5. Finally, we should note that the mole fractions of two solvents in a binary mixture are related to the volume fractions by ... [Pg.170]

Tables 8.1 and 8.2 give calculated ct,a and (l-a,a) values, respectively, for various acids and bases in water at pH 7. Fig. 8.1 shows schematically the speciation of a given acid (or base) as a function of pH. Some example calculations are given in Illustrative Example 8.1. It should be reemphasized that the neutral and ionic forms of a given neutral acid (base) behave very differently in the environment. Depending on the process considered, either the neutral or ionic species may be the dominant factor in the compound s reactivity, even if the relative amount of that... Tables 8.1 and 8.2 give calculated ct,a and (l-a,a) values, respectively, for various acids and bases in water at pH 7. Fig. 8.1 shows schematically the speciation of a given acid (or base) as a function of pH. Some example calculations are given in Illustrative Example 8.1. It should be reemphasized that the neutral and ionic forms of a given neutral acid (base) behave very differently in the environment. Depending on the process considered, either the neutral or ionic species may be the dominant factor in the compound s reactivity, even if the relative amount of that...
We have stated earlier that because of proximity effects, no generally applicable aj values may be derived for ortho substitution. Nevertheless, one can determine a set of apparent 0)ortho values for a specific type of reaction, as for example, for the dissociation of substituted phenols. Table 8.7 gives such apparent O)ortho constants for estimating pKa values of substituted phenols and anilines. Of course, in cases of multiple substitution, substituents may interact with one another, thereby resulting in larger deviations of experimental from predicted pKa values. Some example calculations using the Hammett equation are given in Illustrative Example 8.2. [Pg.265]

No longer can it be claimed that for astrophysical purposes a BH is a Newtonian point mass GR has become indispensable to understand fine points of the observations relating BHs. Yet GR is considered by many opaque and hard to wield. Thus many model builders use GR formulae and results without really understanding where they come from. I try to alleviate the situation by providing in these lectures a little primer to GR together with some example calculations which are both easy to do and have important consequences. I also discuss some concrete issues in BH astrophysics, using whenever feasible GR results here obtained. [Pg.150]

This section presents some example calculations and results from licensing criteria and ASME Code guidelines that have been developed using risk-based safety goals and probabilistic fracture mechanics computational... [Pg.387]

However, it is equally important to also obtain confidence limits for values of x thus calculated from measurements of Y, and indeed these were already stated (again without proof) in Equations [8.30-8.32] (Meier 2000) some example calculations for k = 5 are shown in the... [Pg.410]

Without either spray droplets or flooded pathways, substantial fractions of radionuclides released from the degrading reactor fuel can be retained within the reactor coolant system. Results of some example calculation for radionuclide retention in the reactor coolant systems for various types of accidents are shown in Table III-l. The natural retention of radionuclide vapors oeeurs because the vapors either condense on surfaces or react with these surfaces. Depending on the surface temperature and the duration of its exposure to high temperature steam, the surface material is either ehromium oxide (Cr203) or iron oxide (Fe304 y). Both of these materials are expected to be reactive toward cesium-bearing vapours and strontium or barium vapors. Stainless steel lead screws above the core at Three Mile Island were found to have captured cesium by reaction with silica impurities in the steel. Metallic nickel inclusions in the oxide films on surfaces within the reactor coolant system are reactive toward tellurium whether it is in the metallic state or present as TeO or SnTe. [Pg.34]

In section II of this paper we describe the partial differential equations that make up the model and the constitutive relations used to close it. In section III we describe the solution procedure, and in section IV we describe the results from some example calculations. Finally, in section V we draw some conclusions. [Pg.389]

According to Ehrlich Rohn, the costs of usability can be divided into initial costs and sustaining costs. They identify one-time costs and provide some example calculations of one-time costs of usability. Ehrlich Rohn also identify and provide some example calculations and further discussion of recurring costs. [Pg.514]

Donahue identifies one-time costs and provides some example calculations of onetime costs of usabiiity. He also identifies recurring costs, but does not provide example calculations or further discussion about calculating the recurring costs. [Pg.515]

In the next section, some example calculations of rate coefficients will be given but we note here that a comparison of the rate coefficients predicted from the ADO procedure with experimental values shows that the ADO values tend to underestimate the rate coefficients. [Pg.35]

Calculational methods. Associating the analysis, the knowledge of the property-structure relationships, and the calculation methods has made possible the replacement of costly and arduous test methods by quicker tests whose results are linked by calculations to the characteristic under study. Some examples are the cetane number, in some cases, the octane number, or the characteristics of LPG (refer to Chapter 3). [Pg.296]

The holistic thermodynamic approach based on material (charge, concentration and electron) balances is a firm and valuable tool for a choice of the best a priori conditions of chemical analyses performed in electrolytic systems. Such an approach has been already presented in a series of papers issued in recent years, see [1-4] and references cited therein. In this communication, the approach will be exemplified with electrolytic systems, with special emphasis put on the complex systems where all particular types (acid-base, redox, complexation and precipitation) of chemical equilibria occur in parallel and/or sequentially. All attainable physicochemical knowledge can be involved in calculations and none simplifying assumptions are needed. All analytical prescriptions can be followed. The approach enables all possible (from thermodynamic viewpoint) reactions to be included and all effects resulting from activation barrier(s) and incomplete set of equilibrium data presumed can be tested. The problems involved are presented on some examples of analytical systems considered lately, concerning potentiometric titrations in complex titrand + titrant systems. All calculations were done with use of iterative computer programs MATLAB and DELPHI. [Pg.28]

If both frequency and consequence values are calculated and reported on an absolute basis, then they may be reported graphically in combination with one another (Chapter 3), or simply as the product of frequency and consequence. Table 5 contains some examples of typical risk estimates (frequency and consequence products). Based on absolute risk estimates, you can decide whether the risk of a specific activity exceeds your threshold of risk tolerance (risk goal). If so, analysts can estimate the reduction in risk, given that certain improvements are made, assumptions changed, or operating circumstances eliminated. [Pg.15]

For sampling a relatively small number of sources, a simplified calculation form may be used. Such forms enable the office personnel to perform the arithmetic necessary to arrive at the answers, freeing the technical staff for proposals, tests, and reports. Many of the manufacturers of source-testing equipment include example calculation forms as part of their operating manuals. Some standard sampling methods include calculation forms as a part of the method (8). Many control agencies have developed standard forms for their own use and will supply copies on request. [Pg.547]

Conversion factors can be easily remembered if altered slightly, but not significantly enough to affect shortcut calculations. Here are some examples ... [Pg.388]

Semi-Theoretical and Empirical Velocity Fields Since the use of formulas to calculate the velocities outside an arbitrary opening could be very tedious, only some examples of these formulae are given. These calculations are best done on computers and there are some dedicated programs to calculate and visualize the flow fields outside exhaust openings. There could sometimes be problems when calculating the velocity field outside an opening close to... [Pg.841]

Fig. 4. Some examples of calculated energy bands of a metallic CNT in magnetic fields perpendicular to the axis. Fig. 4. Some examples of calculated energy bands of a metallic CNT in magnetic fields perpendicular to the axis.
In the optical absorption, two different polarisations of light should be considered the electric field is along (parallel or y polarisation) and perpendicular (perpendicular or x) to the axis. Figure 5 shows the energy band of a metallic CNT for flux < )/< )o =0, 1/4 and 1/2 and the process of optical transitions for the parallel and perpendicular polarisations. Some examples of calculated absorption... [Pg.67]

The tables below give some examples of atomic charges and bond orders calculated by various methods as a function of the basis set at the HF level of theory. It is evident that the Mulliken and Ldwdin methods do not converge as the basis set is increased, and the values in general behave unpredictably. Especially the presence of diffuse functions lead to absurd behaviours, as the aug-cc-pVXZ basis sets illustrate for CH4. Note also that... [Pg.232]

Tables 12.1-12.3 below give some examples of the magnitude of each term for two bimolecular reactions (Diels-Alder and Sn2 reactions, forming either one or two molecules as the product) and a unimolecular rearrangement (Claisen reaction). All values have been calculated at the MP2 level with the 6-31G(d) basis for the Diels-Alder and Claisen reactions, and the 6-31+G(d) basis for the S l reaction. The values are given in kcal/mol at a temperature of 300 K (RT = 0.60 kcal/mol). Tables 12.1-12.3 below give some examples of the magnitude of each term for two bimolecular reactions (Diels-Alder and Sn2 reactions, forming either one or two molecules as the product) and a unimolecular rearrangement (Claisen reaction). All values have been calculated at the MP2 level with the 6-31G(d) basis for the Diels-Alder and Claisen reactions, and the 6-31+G(d) basis for the S l reaction. The values are given in kcal/mol at a temperature of 300 K (RT = 0.60 kcal/mol).
The correlation coefficient ranges between 1 and — 1. A perfect positive correlation has r=l, no correlation at all is r = 0, and a perfect negative correlation r= —1. Some examples of correlations are shown in Figure 11.5b. A measure of the significance of a relationship between two variables can be gained by calculating a value of t ... [Pg.231]


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Equilibrium Calculations Some Illustrative Examples

Some Examples

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