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Mutual compensation

The approximations introduced above are mutually compensating to some extent hence the limitation on the size of m/n is not as stringent as otherwise might be inferred. [Pg.427]

Gee and Orr have pointed out that the deviations from theory of the heat of dilution and of the entropy of dilution are to some extent mutually compensating. Hence the theoretical expression for the free energy affords a considerably better working approximation than either Eq. (29) for the heat of dilution or Eq. (28) for the configurational entropy of dilution. One must not overlook the fact that, in spite of its shortcomings, the theory as given here is a vast improvement over classical ideal solution theory in applications to polymer solutions. [Pg.518]

As transpires from equation (2.2), a steady state is established by mutual compensation of diffusion and chemical reaction. The concentration profile is indeed the product of a time-dependent function, i, by a space-dependent function in the exponential. The conditions required for the system to be in zone KP, K small and A large, will often be termed pure kinetic conditions in following analyses. Besides its irreversibility, the main characteristics of the cyclic voltammetric wave in this zone can be derived from its dimensionless representation in Figure 2.2b and its equation (see Section 6.2.1),4 where... [Pg.82]

If electron transport is fast, the system passes from zone R to zone S+R and then to zone SR. In the latter case there is a mutual compensation of diffusion and chemical reaction, making the substrate concentration profile decrease within a thin reaction layer adjacent to the film-solution interface. This situation is similar to what we have termed pure kinetic conditions in the analysis of an EC reaction scheme adjacent to the electrode solution interface developed in Section 2.2.1. From there, if electron transport starts to interfere, one passes from zone SR to zone SR+E and ultimately to zone E, where the response is controlled entirely by electron transport. [Pg.290]

Although the general case may readily be resolved as shown in Section 6.5.1, two limiting situations are of particular practical interest.9 One is when the system obeys pure kinetic conditions (Section 2.2.6), that is, when the diffusion of the cosubsrate and its involvement in a fast enzymatic reaction mutually compensate. Under these conditions, the current responses are governed by the kinetics of the enzymatic reaction. If at the same time, substrate consumption is moderate enough for its concentration to be considered as constant, the current responses are plateau-shaped and obey the following equation (see Section 6.5.1) ... [Pg.301]

The principle of the liquid chromatography under critical conditions (LC CC) was elucidated in Section 16.3.3. The mutual compensation of the exclusion—entropy and the interaction—enthalpy-based retention of macromolecules can be attained when applying in the controlled way the interactions that lead to either adsorption or enthalpic partition. The resulting methods are called LC at the critical adsorption point (LC CAP) or LC at the critical partition point (LC CPP), respectively. The term LC at the point of exclusion-adsorption transition (LC PEAT) was also proposed for the procedures employing compensation of exclusion and adsorption [161]. It is anticipated that also other kinds of enthalpic interactions, for example the ion interactions between column packing and macromolecules can be utilized for the exclusion-interaction compensation. [Pg.478]

The difference between the two meanings is crucial to the status of strain, induced fit, and nonproductive binding in catalysis. As we discussed in Chapter 12 and as we shall amplify below, these do not affect biological specificity, since they alter kcat and KM in a mutually compensating manner without altering kcJKM. [Pg.526]

The experimental and predicted profiles for adsorption from a mixture 5 x 10 H phenol and 5 x 10 H dodecyl benzene sulfonate are shown in Figure 15. The rate of adsorption of dodecyl benezene sulfonate is faster than predicted, and for phenol, the rate is slower than predicted. However, the shape of the predicted profiles for both solutes closely parallel the experimental curves. Similar trends may be noted in Figure 16 for the adsorption rates from a 10 4 H phenol and 10 4 H dodecyl benzene sulfonate mixture. The mixture equilibrium data for these solutes have been correlated satisfactorily. Thus, it would appear that solute-solute interactions are affecting the diffusional flux of each solute. Moreover, from Figure 17 for the total concentrations, it may be seen that the interaction effects are mutually compensating. The total concentration profiles for both... [Pg.45]

The lack of the dominant computed ROA couplet is more difficult to understand. Calculations for the gas phase, with basis sets known to reproduce experimental data well [37], invariably lead to a couplet of substantial size. Fermi resonance should conserve ROA intensity the same way as it conserves Raman intensity. A mutual compensation of the ROA intensities of the in-phase and out-of-phase vibrations by mixing cannot occur. [Pg.232]

The cause of concentration polarization is the slow rate of diffusion of ions which cannot counterbalance the concentration variations in the close proximity of both electrodes arising from the discharge or formation of ions. Let us imagine, e. g. the electrolysis of a silver nitrate solution between two silver electrodes. When no current is flowing through the system the potentials at both electrodes are of the same value and are mutually compensated. As soon as electrolysis starts, the concentration of Ag+ ions will begin to rise owing to the dissolution of silver at the anode on the contrary the concentration of these ions round the cathode will fall because the deposition of metallic silver will here take place. The concentration differences produced will never be fully compensated... [Pg.131]

The drop of water decomposition voltage and the decrease of current efficiency are mutually compensated so that a certain amount of the gas produced will require the same energy consumption, or only somewhat lower, at increased pressure, as at atmospheric pressure. [Pg.228]

It is of importance for a knowledge of the forces acting between colloidal particles that the greatest distance at which the London forces are still important is not the radius of the atom but in fact of the order of magnitude of the radius of the particle itself, since the interaction between all the atoms in each of the colloidal particles must be summed, and this interaction, therefore, will increase with increasing size of the particles (Hamaker)1. This is quite different from, for example, the interaction between particles with a crystal lattice in which only purely electrostatic forces would act in this case the radius of action remains, even for large particles, of the order of the lattice constant and there is only a question of a surface action. The effect of the more deeply situated parts of the lattice does not appear outside on account of the mutual compensation of the action of the oppositely charged ions. [Pg.332]

Figure 4.6-8 Optical rotation exhibited by a 0.2 mm thick sample of a mixture of cholesteryl chloride and cholesteryl myristate (molar ratio 1.67) at 1900 cm Scanning the temperature changes the pitch. At 59.5 °C the pitch corresponds to 1900 cm , at about 48 °C the twisting influences of the mixture components are mutually compensated so that the sample is nematic, at lower temperatures the structure is countercurrent. Above and below T em the rotatory dispersion follows a curve as derived by de Vries (1951). Figure 4.6-8 Optical rotation exhibited by a 0.2 mm thick sample of a mixture of cholesteryl chloride and cholesteryl myristate (molar ratio 1.67) at 1900 cm Scanning the temperature changes the pitch. At 59.5 °C the pitch corresponds to 1900 cm , at about 48 °C the twisting influences of the mixture components are mutually compensated so that the sample is nematic, at lower temperatures the structure is countercurrent. Above and below T em the rotatory dispersion follows a curve as derived by de Vries (1951).
H GH2=GH— GH—GH3 and GH3 --GH--GH=GH2H+ when discussing the reactivity of the molecule but owing to the symmetry of the molecule, the moments are mutually compensated and the molecule has zero dipole moment. [Pg.214]

The di-substituted halogen derivatives of ethylene, in which the halogen atoms are located on different carbon atoms form rij-and transAsomevs, In /ra j-dichlorethylene owing to the mutual compensation of the moments... [Pg.217]

It should be emphasized that these slopes are only valid when n = I and the wave is purely kinetic, that is, the chemical reaction is so fast that a stationary state is established by mutual compensation of the chemical reaction of the intermediate... [Pg.523]

This can be explained by the fact that in a polymer molecule (Fig. 78b) the longitudinal components of monomer unit dipoles mh are mutually compensated and the main part in the observed EB is played by normal components of monomer unit dipoles, mi, which can be parallel to the main chain of the macromolecule owing to its comb-like structure. In other words, in molecules of comb-like polymers containing mesogenic side chains, the orientations of the Mi components of the side group dipoles are correlated with each other. As a result, the macromolecule as a whole or part of it can exhibit a considerable dipole moment m in the direction of the main chain L (Fig, 78b). The existence of this dipole accounts for the orientation of the main chain in the field direction leading to negative EB. [Pg.191]

Figure 17.9 shows the principle of the antireflection/antistatic thin hlms formed on the panel surface. There is a layer of hhn having a high refractive index (Sn02) and a layer of him having a low refractive index (Si02). Light rehection is reduced since they are mutually compensated by the interference effect on all areas of the interface between these layers of him. [Pg.210]


See other pages where Mutual compensation is mentioned: [Pg.1081]    [Pg.163]    [Pg.17]    [Pg.28]    [Pg.221]    [Pg.58]    [Pg.24]    [Pg.290]    [Pg.15]    [Pg.400]    [Pg.451]    [Pg.615]    [Pg.460]    [Pg.461]    [Pg.119]    [Pg.357]    [Pg.154]    [Pg.135]    [Pg.34]    [Pg.161]    [Pg.208]    [Pg.215]    [Pg.10]    [Pg.24]    [Pg.166]    [Pg.237]    [Pg.335]    [Pg.335]    [Pg.617]    [Pg.628]    [Pg.481]    [Pg.95]   
See also in sourсe #XX -- [ Pg.208 ]




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