Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Equality correspondence, solution

As already discussed in Chapter 1, the relative tendency of a surfactant component to adsorb on a given surface or to form micelles can vary greatly with surfactant structure. The adsorption of each component could be measured below the CMC at various concentrations of each surfactant in a mixture. A matrix could be constructed to tabulate the (hopefully unique) monomer concentration of each component in the mixture corresponding to any combination of adsorption levels for the various components present. For example, for a binary system of surfactants A and B, when adsorption of A is 0.5 mmole/g and that of B is 0.3 mmole/g, there should be only one unique combination of monomer concentrations of surfactant A and of surfactant B which would result in this adsorption (e.g., 1 mM of A and 1.5 mM of B). Uell above the CMC, where most of the surfactant in solution is present as micelles, micellar composition is approximately equal to solution composition and is, therefore, known. If individual surfactant component adsorption is also measured here, it would allow computation of each surfactant monomer concentration (from the aforementioned matrix) in equilibrium with the mixed micelles. Other processes dependent on monomer concentration or surfactant component activities only could also be used in a similar fashion to determine monomer—micelle equilibrium. [Pg.326]

Figure 4 shows data for a mechanical blend of equal weights of Polymers A and E. The two-phase nature of this blend is immediately obvious from the observation of separate transitions for the component polymers which are almost unshifted from their positions in Figures 1 and 2. The corresponding solution blend is shown in Figure 5. The dif-... Figure 4 shows data for a mechanical blend of equal weights of Polymers A and E. The two-phase nature of this blend is immediately obvious from the observation of separate transitions for the component polymers which are almost unshifted from their positions in Figures 1 and 2. The corresponding solution blend is shown in Figure 5. The dif-...
Freqnamiy, gases and liquids involved in gas absorption operations are quite dilute. When this is the case, Y is approximetely equal to y and X is approximately equal to x. Also, the total molar mass flow rates LM and GM are approximately equal to (he corresponding solute-free flow rales and G u so that the following approximate equation can be used ... [Pg.352]

One aspect that reflects the electronic configuration of fullerenes relates to the electrochemically induced reduction and oxidation processes in solution. In good agreement with the tlireefold degenerate LUMO, the redox chemistry of [60]fullerene, investigated primarily with cyclic voltammetry and Osteryoung square wave voltammetry, unravels six reversible, one-electron reduction steps with potentials that are equally separated from each other. The separation between any two successive reduction steps is -450 50 mV. The low reduction potential (only -0.44 V versus SCE) of the process, that corresponds to the generation of the rt-radical anion 131,109,110,111 and 1121, deserves special attention. [Pg.2418]

Gaussian Elimination, hi the most elementary use of Gaussian elimination, the first of a pair of simultaneous equations is multiplied by a constant so as to make one of its coefficients equal to the corresponding coefficient in the second equation. Subtraction eliminates one term in the second equation, permitting solution of the equation pair. [Pg.47]

For reasonable quantitative accuracy, peak maxima must be at least 4cr apart. If so, then Rs = 1.0, which corresponds approximately to a 3% overlap of peak areas. A value of Rs = 1.5 (for 6cr) represents essentially complete resolution with only 0.2% overlap of peak areas. These criteria pertain to roughly equal solute concentrations. [Pg.1107]

In this chapter we analyse a wide class of equilibrium problems with cracks. It is well known that the classical approach to the crack problem is characterized by the equality type boundary conditions considered at the crack faces, in particular, the crack faces are considered to be stress-free (Cherepanov, 1979, 1983 Kachanov, 1974 Morozov, 1984). This means that displacements found as solutions of these boundary value problems do not satisfy nonpenetration conditions. There are practical examples showing that interpenetration of crack faces may occur in these cases. An essential feature of our consideration is that restrictions of Signorini type are considered at the crack faces which do not allow the opposite crack faces to penetrate each other. The restrictions can be written as inequalities for the displacement vector. As a result a complete set of boundary conditions at crack faces is written as a system of equations and inequalities. The presence of inequality type boundary conditions implies the boundary problems to be nonlinear, which requires the investigation of corresponding boundary value problems. In the chapter, plates and shells with cracks are considered. Properties of solutions are established existence of solutions, regularity up to the crack faces, convergence of solutions as parameters of a system are varying and so on. We analyse different constitutive laws elastic, viscoelastic. [Pg.69]

If appropriate enthalpy data are unavailable, estimates can be obtained by first defining reference states for both solute and solvent. Often the most convenient reference states are crystalline solute and pure solvent at an arbitrarily chosen reference temperature. The reference temperature selected usually corresponds to that at which the heat of crystallization A/ of the solute is known. The heat of crystallization is approximately equal to the negative of the heat of solution. For example, if the heat of crystallization is known at then reasonable reference conditions would be the solute as a soUd and the solvent as a Uquid, both at The specific enthalpies then could be evaluated as... [Pg.341]

As an idealization of the classified-fines removal operation, assume that two streams are withdrawn from the crystallizer, one corresponding to the product stream and the other a fines removal stream. Such an arrangement is shown schematically in Figure 14. The flow rate of the clear solution in the product stream is designated and the flow rate of the clear solution in the fines removal stream is set as (R — 1) - Furthermore, assume that the device used to separate fines from larger crystals functions so that only crystals below an arbitrary size are in the fines removal stream and that all crystals below size have an equal probabiHty of being removed in the fines removal stream. Under these conditions, the crystal size distribution is characterized by two mean residence times, one for the fines and the other for crystals larger than These quantities are related by the equations... [Pg.351]

For the gravity discharge case, the height of the fluid at maximum vacuum, which is the point at which air would begin to backflow into the tank, is determined by Eq. (26-54). Equation (26-55) calculates the corresponding vacuum in the tank s headspace at this hquid height. Since the drain nozzle is open to the atmosphere, this solution is a static force balance that is satisfied when the sum of the internal pressure and the remaining fluid head is equal to the atmospheric pressure. [Pg.2337]

A gene encoding this sequence was synthesized and the corresponding protein, called Janus, was expressed, purified, and characterized. The atomic structure of this protein has not been determined at the time of writing but circular dichroic and NMR spectra show very clear differences from B1 and equally clear similarities to Rop. The protein is a dimer in solution like Rop and thermodynamic data indicate that it is a stably folded protein and not a molten globule fold like several other designed proteins. [Pg.370]

These formulae explain the scission products of the two alkaloids and the conversion of evodiamine into rutaecarpine, and were accepted by Asahina. A partial synthesis of rutaecarpine was effected by Asahina, Irie and Ohta, who prepared the o-nitrobenzoyl derivative of 3-)3-amino-ethylindole-2-carboxylic acid, and reduced this to the corresponding amine (partial formula I), which on warming with phosphorus oxychloride in carbon tetrachloride solution furnished rutaecarpine. This synthesis was completed in 1928 by the same authors by the preparation of 3-)S-amino-ethylindole-2-carboxylic acid by the action of alcoholic potassium hydroxide on 2-keto-2 3 4 5-tetrahydro-3-carboline. An equally simple synthesis was effected almost simultaneously by Asahina, Manske and Robinson, who condensed methyl anthranilate with 2-keto-2 3 4 5-tetrahydro-3-carboline (for notation, see p. 492) by the use of phosphorus trichloride (see partial formulae II). Ohta has also synthesised rutaecarpine by heating a mixture of 2-keto-2 3 4 5-tetrahydrocarboline with isatoic anhydride at 195° for 20 minutes. [Pg.499]


See other pages where Equality correspondence, solution is mentioned: [Pg.263]    [Pg.88]    [Pg.142]    [Pg.52]    [Pg.769]    [Pg.816]    [Pg.231]    [Pg.450]    [Pg.327]    [Pg.508]    [Pg.2971]    [Pg.54]    [Pg.385]    [Pg.172]    [Pg.631]    [Pg.658]    [Pg.72]    [Pg.368]    [Pg.108]    [Pg.328]    [Pg.1365]    [Pg.1416]    [Pg.595]    [Pg.91]    [Pg.62]    [Pg.998]    [Pg.447]    [Pg.80]    [Pg.55]    [Pg.83]    [Pg.143]    [Pg.45]    [Pg.18]    [Pg.101]    [Pg.287]    [Pg.475]    [Pg.600]    [Pg.19]   
See also in sourсe #XX -- [ Pg.345 ]




SEARCH



Equal

Equaling

Equality

Equalization

© 2024 chempedia.info