Destabilizing forces

Figure 13.6 The relationship between Tm (°C) and benzyl alcohol content (obtained from the data in Figure 13.4) expressed as a percentage (w/w). Note that the relationship can be fitted to a line having a slope that describes the destabilizing force of the preservative. The dashed line designated as A illustrates a preservative force that is less destabilizing in contrast to the dashed line designated as B that is more destabilizing than benzyl alcohol.

Equation (45) represents a necessary condition for trapping, but it is also necessary to have sufficient power to generate forces larger than destabilizing forces, such as Brownian motion. As a result, the additional requirement for trapping is... 

Caution should be taken regarding the disposition of the material treated by thermal desorption because the treatment process may alter the physical properties of the material. For example, the matrix material could be susceptible to such destabilizing forces as liquefication, where pore pressures are able to weaken the material on sloped areas or places where materials must support a load (i.e., roads for vehicles, subsurfaces of structures, etc.). 

Enzymes are a class of macromolecules with the ability both to bind small molecules and to effect reaction. Stabilizing forces such as hydrophobic effects only slightly dominate destabilizing forces such as Coulombic forces of equal polarity thus the Gibbs free enthalpy of formation of proteins, AGformation, is only weakly negative. 

The electric field experiment shown here can be considered as a test case for the quantitative nature of capillary instability experiments. It shows the precision, with which the capillary wave pattern reflects the underlying destabilizing force. In the case of electric fields, this force is well understood. Therefore, the good fit in Fig. 1.10b demonstrates the use of film instability experiments as a quantitative tool to measure interfacial forces. The application of this technique to forces that are much less well understood is described in the following section. 

We have previously reported that the destabilizing force is a consequence of the heat diffusion mechanism (for details see ref. [36]). The diffusive heat flux across a medium with thermal conductivity k is given by Fourier s law. 

A second approach makes use of capillary surface instabilities that occur in the presence of a destabilizing surface force. Since such a instability mirrors the details of the destabilizing force field, it can be employed as a sensitive tool to study and explore forces that act at the... 

The calculated relative energies of the three isomerical dihydrodiazetes 14 (0.0) > 17 (—8.21) > 18 (—9.51 kcal mol-1) are in the same order indicating that there is no special stabilization (or destabilization) force in any isomers. 

Vertical transport and gravitational circulation in estuaries are influenced by both stratification and turbulent mixing, which result from the destabilizing forces of tides and/or wind processes. Under highly stratified conditions, two-layered flow is largely determined by the interaction of baroclinic and barotropic forcing. 

Turbulent mixing mixing that results from the destabilizing forces of tides and/or winds. Turnover time time required to remove all the materials in a reservoir, or the average time spent by elements in a reservoir. 

Steric stabilization differs from electrostatic stabilization in not being a function of a net force, but of the thickness of an adsorbed layer. When < >, equals 5-10%, stabilizing and destabilizing forces extend beyond the length of the electrostatic, interparticle barrier (Cabane et al., 1989). At this distance, attraction and repulsion are inconsequential, and electrolytes therefore have little effect. Bergenstahl (1988) proposed that the steric stabilization of emulsions by gums in the presence of a surfactant involves adsorption of the gum on the surfactant to form a combined structure constituted by a primary surfactant layer covered by an adsorbed polymer layer. 

Above, we showed how a finely modulated balancing act between stabilizing and destabilizing forces yields marginally stable protein structures. We now examine in more detail how the same types of noncovalent interactions are used in differently thermally adapted proteins to achieve appropriate levels of structural stability. The adaptive changes discussed below are relevant to both global protein stability and to the establishment of the appropriate balance between stability and flexibility required for... 

In spite of the droplets being destabilized electrostatically, no evidence of droplet coalescence is seen. By the same token, an electrostatically stabilized emulsion might still coalesce and separate, sediment, or cream if other destabilizing forces overbalance the electrostatic component. Creaming refers to concentration of the dispersed phase without completely separating the oil and water phases. 

In this chapter we will describe certain schemes by which some of these destabilizing forces might be checked. Of particular interest is the use of additive... 

In electrostatic interactions the potentially destabilizing force of the phosphate group charges (repulsion between nearby negative charges) is offset by the binding of magnesium ions and polycationic molecules such as the polyamines and histones. 

Another source for a destabilizing force in thin films is electrostatic pressure. It has been found in substrate-fluid-fluid systems that if the central fluid layer is a dielectric and the substrate and top fluid layer are both conducting (with differing work functions), then an electric field across the dielectric can drive instabilities [21, 22]. In other words, the presence of the two different work functions (of the... 

The thermodynamic stability of the native conformation arises from the minimization of the overall free energy of interaction. It results from a unique balance between large stabilizing and large destabilizing forces and appears to be only marginal. 

The particles plucked out of the rock skeleton by fluid flow and the swelling of clay materials may block pore throats, locally increase the pressure gradient, and thus increase the destabilizing force. 

E Young s modulus. Pa Fc capillary bond force, N F( destabilizing force from fluid gradient. Pa k absolute permeability of reservoir, m k , k,o water and oil relative permeabilities, m"... 

This common transposition of terms is, in my view, an attempt to contain the destabilizing force of racial antagonism, an evasion of history and material context. See following note. 

They also computed the interior gas fluxes by taking derivatives of the velocity potential, which comprises the integral of the derivatives of Green s function of (18.4). The BEM computations showed that the escaping air velocity was more than triple the drop s impact speed. This escaping air provides sufficient destabilizing force to rupture the drop into splashing. 

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