Plateau effect

S.K. Sinha W.D. Patwardhan, Explosiv-stoffe 16 (10), 223-25 (1968) CA 70,49144 (1969) The mechanism causing the plateau effect in the combustion of proplnts with ad-mixt of Pb compds (ie, the independence of pressure of the combustion rate in a certain range) is discussed. This effect is caused by the transport of free Pb alkyl radicals from the foam zone to the fizz zone, which decomn there, causing a more efficient combustion, and increase the temp of this zone by reaction1 with NO. An increase of pressure is assumed to displace the free radicals from this zone because of the increase of the collision rate . this leads... 

When the curve of a particular property (usually tensile strength) of vulcanised rubber plotted against time of vulcanisation shows a levelling off or only a slow fall after the maximum has been reached, the compound or compounding ingredient under test is said to be flat curing, to have flat curing characteristics or to show a plateau effect. 

Maximum productivity is given by the shortest possible time of cure, provided the selected time and temperature do not produce an unacceptable level of defects or early failures in service. Sufficient cure must be given to prevent porosity, since badly undercured rubber will sponge at pressure release. It is better to risk a slight overcure rather than an undercure, since if the curatives are correctly chosen (in type and quantity) the compound should show a plateau effect, which means that a reasonable overcure will not have any marked effect on the physical properties of the product. 

At Coventry University [20] we have obtained similar results to Tu under conventional (silent) conditions. Our initial thoughts were that if the effect of the tail off was either a consequence of mass transfer to the electrode, or a consequence of some problem with the diffusion layer, then ultrasound might be expected to have an effect and thus improve the plating rate. Investigations in the presence of ultrasound and at various pH values did not significantly affect the plating characteristics i. e. the plateau effect still remained. However, the overall efficiency in the presence of ultrasound was affected (Fig. 6.10). 

An effect of type A (Figure 14-1) is present in the ordinary d-SoC at a low or zero level and as the d-ASC deepens, at some threshold the effect starts to become more intense. Then it reaches some maximum level of intensity and stays there, even though depth increases. This rise-and-plateau effect is often found with marijuana intoxication. The feeling that time is slowing down, for example, does not become manifest until a moderately great depth of intoxication is reached then it starts to manifest itself, steadily get stronger (time seems to slow even more), and finally plateaus at a maximum level, even if the person feels more intoxicated later 105. ... 

Quantum saturation, the plateau effect, and defect tails... 

When concentrations of solute atoms are low (i.e. Ag less than -0.01 mol % to -2 mol %, depending on the mineral), the fields generated by the defects will not overlap, and the dependence of T on composition will be very weak. Consequently, the T -Xb curve flattens as Ag approaches 0 to create a plateau effect. 

Salje (1995) models the excess energies associated with the plateau effect for three classes of substitutions (1) Solutes that generate random fields that interact with the host ... 

The term r/ refers to the critical temperature for the pure phase (Xb = 0), and the result demonstrates that Tc(Xb) is proportional to xf rather than to, as is the case when concentrations of solute are high. The resulting profile of the variation of the critical temperature with composition actually is concave up and represents an inverse plateau. When solutes are not randomly distributed but present as clusters, Salje (1995) argues that the proportionality of Tc goes as xf. This profile is concave downward and more closely resembles the plateau effects measured experimentally. 

K when exceeds -0.47. Plateau effects extend from = 0 to 0.02 suggesting an interaction range for K substitutions of -10 A (Hayward et al. 

Salje EKH (1995) Chemical mixing and stmctural phase transitions The plateau effect and oscillatoiy zoning near surfaces and interfaces. Eur J Mineral 7 791-806 Salje EKH (1999) Ferroelastic phase transitions and mesoscopic stractures. Ferroelectrics 221 1-7 Salje E, Bismayer U, Wrack B, Hensler J (1991) Influence of lattice imperfections on the transition temperatures of structural phase transitions The plateau effect. Phase Trans 35 61-74 Salje E, Devarajan V (1981) Potts model and phase transition in lead phosphate Pb3(P04)2. J Phys C 14 L1029-L1035... 

Figure 14.9 Sample cumulative skin permeation patterns following finite and infinite dosing regimes. With infinite dose, permeation normally reaches a steady-state flux region, from which it is possible to calculate permeability coefficients and diffusional lag times. In finite dosing the permeation profile normally exhibits a plateauing effect as a result of donor depletion.

An effect of type (Figure 14-5) is manifested strongly in the ordinary d-SoC and is not changed up to a certain depth in the d-ASC. But then it begins to decrease in intensity with increasing depth or, as shown in this example, returns more or less intensely at a greater depth, perhaps in a step-rise-and-plateau effect. An... 

The plateau effect also demonstrates that, once the product has reached its final drying temperature, there is little value in extending the drying period beyond a few hours, and the practice of lowering the temperature for the final drying period is of no value if the product has already reached a steady state at a higher temperature. 

Starting with a certain amount of product (ca. 0.3 to 1 pmol) during the PCR process, a plateau effect decreases the efficiency significantly. This is due to the accumulation... 

Increases in dose result in nonlinear relationship between total plasma concentrations of VPA and dose due to saturable protein binding (plateau effect) however, there is a linear relationship between unbound VPA plasma concentrations and dose. 

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