Cavity expansion

The structure based virtual screening process includes also the use of some keywords. With these keywords FLAP fdters out matches and keeps them only if they make sense in terms of binding site shape. FLAP can also allow additional binding site volume (cavity expansion, useful when the protein structure under investigation is an homology model) and with the use of regions (definition of a sphere within each pharmacophore needs to have at least one point) or selection of a probe (enforcing a particular feature to be present in the calculated pharmacophores) certain constraints can also be added. 

Functional dependence of negative pressure on deviatric stress for cavity expansion... 

The cavities thus formed will expand. This would suggest that the increase in total surface energy due to the creation of new surface would be a contributor to the tack force. However, in an analysis of cavity expansion within a polyisobutene oil, Hoffman and Myers— found that surface tension contributed only 7 percent and the viscosity contributed 93 percent to the work of separation of the oil film. 

Here was adopted for simplicity that a = 1/2 and a 1 (the latter inequality is satisfied for bubbles with Ro > >1 mkm). Phase plot of diis equation is presented in Figure 7.2.2. It is seen that for k = -1 (collapsing cavity) z —>Zi as t —> if Zq > Zj. The stationary point z = Zj is unstable. The rate of die cavity collapse z = Zj in the asymptotic regime satisfies inequality Zp < Z < (f where Zp = -RCp is equal to the collapse rate of the cavity in a pure viscous fluid with viscosity of polymeric solution ii. It means diat the cavity closure in viscoelastic solution of polymer at asymptotic stage is slower dian in a viscous liquid with the same equilibrium viscosity. On the contrary, die expansion under the same conditions is faster at k = 1 Zp pure solvent widi die viscosity (1- P)q. Tliis result is explained by different behavior of the stress tensor component controlling the fluid rheology effect on the cav-... 

The top Pyrex glass provides a hermetically sealed cavity so that the polysDicon heater can heat up the air in the cavity. Expansion of the hot air in the cavity will compress the silicon membrane to perform a pumping action in the pumping chamber. The bottom Pyrex glass seals the pump chamber as well as provides the input and output holes for fluid flow in and out of the pump chamber. 

For instance, data from the vane shear test in clays are usually analyzed within a limit equilibrium solution, whereas pressuremeter results are considered within cylindrical cavity expansion. Alternative theoretical solutions proposed for analysis of CPT data include limit plasticity, strain path method, finite elements, discrete elements, hybrid cavity expansion-critical state, and dislocation theory. Usually, the approaches are established for two extreme cases of drainage, either (a) undrained, applied to clays or (b) fully-drained, applied to sands. In reality, many possible scenarios lie between the two conditions, as discussed by Randolph (2004) and Schneider et al. (2008). 

V.K. Luk, M.J. Forrestal, D.E. Amos, Dynamic spherical cavity expansion of strainhardening materials. J. Appl. Mech.-Trans. ASME 58(1), 1-6 (1991)... 

These criteria describe different states of local excitation and deformation of chain segments. The stress bias criterion [86, 139] refers implicitely to two mechanisms cavitation in a dilatational stress field and stabilization of cavities through a deviatoric stress component. These mechanisms have been more explicitely considered in the mathematical model of cavity expansion in a rigid plastic by Haward et al. [137] and in the molecular models by Argon [152] and Kausch [11]. 

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