Penetration dynamics

Clearly, the obeerved permeability is a normalized integration of (he product of a kinetic fuclor aad a thermodynamic factor across the entire membrane from upstream ("condition 2") to downstream ("condition 1"). The thermodynamic lenn dC/dp is deiennined by polymer-penetrant interactions. The kinetic term 22(C) is deiennined by polymer-penetrant dynamics and requires localization of a sufficiently large transient packet of volume contiguous to the penetrant to petinit it to execute a so-called diffusive jump. 

Studies on the penetration dynamics, i.e., the time dependence of the surface pressure of a penetration system during the adsorption of the soluble surfactant, are rather scarce [112, 113, 114, 115, 116]. 

A much more complex behaviour is observed for the process of penetration of various proteins into phospholipid monolayers. This behaviour depends strongly on the protein and the solution properties although some common features are observed. Fainerman et al. [116] studied the P-lactoglobulin penetration dynamics into DPPC monolayers. For a (i-lactoglobulin bulk concentration of 510 mol/l and molar areas of the lipid larger than the critical value, A > A, first order phase transitions are observed. Thus, two-dimensional condensed phase are formed although at these molar area values the pure DPPC monolayer exists only in the fluid-like state and does not form any domains. The first-order phase transition in the DPPC monolayer becomes visible by the characteristic break point in the dynamic surface pressure curve Fl(t) (see Fig. 4.50). 

Fig, 4.50 Penetration dynamics for P-lactoglobulin penetration at A = 1.20 nm per one DPPC molecule. The n(t) penetration kinetics curve indicates the first order phase transition point after 29 min. 

Shi Biming, Yu Qixiang, Wang Kai, 2006. Test Research on coal seam penetrability dynamic changing law by far-distance protecting stratum mining. Chinese Journal of Rock Mechanics and Engineering, 09. 

Hearle JWS. Research on a basic study of the high speed penetration dynamics of textile materials. Manchester University of Manchester 1974. p. 51. 

FIG. 8. Characteristic 40-50 year incremental market penetration dynamics of major... 

The penetration velocities of projectiles interacting with explosives initiated by the projectile have been found to be much lower than the penetration velocities of inerts of the same density. Studies of projectile penetration dynamics in inert and reactive targets have been performed using the Eulerian reactive hydrodynamic code 2DE described in Appendix C. 

Verezub, O., Kaptay, G., Matsushita, T., Mukai, K. (2005). Penetration dynamics of solid particles into liquids high-speed experimental results and modelling. Materials Science Forum, 473-474, 429-434. 

Transportable high-current KEC-25M betatron on 25 MeV energy with power dose of radiation on 1 m away from the target of 30 Gr/min is the source of penetrating radiation intended for flaw detection in field conditions and radiation visualization of dynamic processes [2]. 

In Fig. III-7 we show a molecular dynamics computation for the density profile and pressure difference P - p across the interface of an argonlike system [66] (see also Refs. 67, 68 and citations therein). Similar calculations have been made of 5 in Eq. III-20 [69, 70]. Monte Carlo calculations of the density profile of the vapor-liquid interface of magnesium how stratification penetrating about three atomic diameters into the liquid [71]. Experimental measurement of the transverse structure of the vapor-liquid interface of mercury and gallium showed structures that were indistinguishable from that of the bulk fluids [72, 73]. 

The energetics and kinetics of film formation appear to be especially important when two or more solutes are present, since now the matter of monolayer penetration or complex formation enters the picture (see Section IV-7). Schul-man and co-workers [77, 78], in particular, noted that especially stable emulsions result when the adsorbed film of surfactant material forms strong penetration complexes with a species present in the oil phase. The stabilizing effect of such mixed films may lie in their slow desorption or elevated viscosity. The dynamic effects of surfactant transport have been investigated by Shah and coworkers [22] who show the correlation between micellar lifetime and droplet size. More stable micelles are unable to rapidly transport surfactant from the bulk to the surface, and hence they support emulsions containing larger droplets. 

Fig. 1. Deceleration and penetration curves from dynamic impact tester. Time vs distance penetrated (A) and deceleration (B). Distance between vertical...

For dynamic water resistance, the BaUy Penetrometer Test, lUP/10 (52) measures water penetration. 

For dynamic water resistance, the Maeser Test, ASTM D2099 (53) measures the number of flexes and water penetration. The flex imparted to the leather is a magnification of the flex given the vamp of a shoe ia actual wear. 

In the irreversible limit R < 0.1), the adsorption front within the particle approaches a shock transition separating an inner core into which the adsorbate has not yet penetrated from an outer layer in which the adsorbed phase concentration is uniform at the saturation value. The dynamics of this process is described approximately by the shrinldng-core model [Yagi and Kunii, Chem. Eng. (Japan), 19, 500 (1955)]. For an infinite fluid volume, the solution is ... 

Dehn, J., The Particle Dynamics of Target Penetration, US Army Ballistic Research Laboratory Technical Report No. ARBRL-TR-02188, Aberdeen Proving Ground, MD, 109 pp., September 1979. 

Embrittlement embrittlement and for improperly heat treated steel, both of which give intergranular cracks. (Intercrystalline penetration by molten metals is also considered SCC). Other steels in caustic nitrates and some chloride solutions. Brass in aqueous ammonia and sulfur dioxide. physical environments. bases of small corrosion pits, and cracks form with vicious circle of additional corrosion and further crack propagation until failure occurs. Stresses may be dynamic, static, or residual. stress relieve susceptible materials. Consider the new superaustenitic stainless steels. 

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