Quiescent condition

In such an environment an inner lining of acid-resistant brick is often used. Thermal cycling may also disrupt the film. Acid of more than 85 Vo concentration tends to dissolve the lead sulphate film, although lead has been used in cold quiescent conditions with concentrations of over 90 Vo. 

Under quiescent conditions, polymer solutions are divided into four categories depending on the average distance separating the centers of mass of the molecular coils the dilute, the semi-dilute (or semi-concentrated), the concentrated and the entangled state. 

Polymer solutions are considered as dilute when the degree of coil interaction is negligible. Under quiescent conditions, contacts are practically absent when the polymer concentration is below some limiting value (c ) defined by [167] ... 

Siebers, D. and Higgins, B., Elame Lift-Off on Direct Injection Diesel Sprays under Quiescent Conditions, SAE, 2001-01-0530,2001. 

Under quiescent conditions, the rate of solution of S within the liquid, is determined by molecular diffusion and is described by Pick s law, where... 

We examine briefly some specific instances starting with syndiotactic polypropylene (sPP). Aside from the already discussed hexagonal mesophase which can be obtained both drawing fibers and under quiescent conditions, this polymer presents four crystalline forms phases I [73] and II [74-76] where chains adopt the (T2G2)n helical conformation, forms III [30] and... 

A rheological measurement is a useful tool for probing the microstructural properties of a sample. If we are able to perform experiments at low stresses or strains the spatial arrangement of the particles and molecules that make up the system are only slightly perturbed by the measurement. We can assume that the response is characteristic of the microstructure in quiescent conditions. Here our convective motion due to the applied deformation is less than that of Brownian diffusion. The ratio of these terms is the Peclet number and is much less than unity. In Equation (5.1) we have written the Peclet number in terms of stresses ... 

Study of the Crystalline Regions. According to our morphological studies, the crystalline structure of UHMWPE pseudo-gel was different under different sample preparations. For example, spherulites and lamellar single crystal stacks were observed when the pseudo-gel was prepared under quiescent conditions, shish-kebab crystals under stirring conditions, and a mixture of single and shish-kebab crystals under uncontrolled conditions (10). 

Under shear flow, the minimum center-to-center separation, r, between the particles will be in the interval 2Rs < r < L i.e., at the high-shear limit r = 2R, and at quiescent conditions r = L. An analysis of the flow behavior in this case leads to the following expression for the zero shear rate (i.e., Pe < 1) limit of the relative viscosity ... 

Under quiescent conditions a concentration substantially in excess of normal solubility or a temperature lower than the normal saturation temperature can be maintained. The maximum supersaturation appears to be a fairly reproducible quantity, but is reduced or even eliminated by stirring or by the introduction of dust or seed crystals. Some data are shown in Figure 16.1(c) and in Table 16.1. They are expressed as AC = C — Csat or as AC/Csat or as AT=T- Fsat. According to the data of Table 16.1(d), subcooling correlates roughly with the heat of solution. The increments AC and AT can be quite substantial quantities. 

At the end of the preconcentration period, the forced convection is stopped and a 15-s rest period is employed to establish a uniform concentration (within the mercury) and to ensure that the subsequent stripping step is performed under quiescent conditions. 

As with previous methods, artificially layered deposits may be obtained from a single chemical solution using a specially designed cell, for instance, with adjustable anode-cathode gap (see Fig. 17.3). This two-compartment cell may be constructed from Lucite with deposition conducted in one compartment, and KC1 solution placed in the other. A calomel reference electrode immersed in this KC1 solution should be coupled to the flat-plate cathode by a salt bridge, ending in a capillary on the deposition side. The specimen electrode is fixed, and the counter-electrode is movable using, say, a micrometer. Electrodeposition is best conducted under quiescent conditions. 

Allow competition step on the immunosensor surface to proceed for 30 min under quiescent conditions. 

First, the kinetic contribution is discussed. Under quiescent conditions,... 

The membrane emulsification can be considered as a case of microdevice emulsification process [17, 18] in which the porous membrane is used as microdevices. Membrane emulsification carried out in quiescent conditions is also referred to as static membrane emulsification, while membrane emulsification carried our in moving conditions (either the membrane, i.e., rotating module, or the phase, i.e., crossflow) is also referred to as dynamic membrane emulsification (Figure 21.2(b)). 

Emulsification devices where the membrane is immersed in a stirred vessel containing the continuous phase, so as to obtain a batch emulsification device operating in deadend emulsification mode, have also been developed (Figure 21.13). Both flat-sheet and tubular membranes are used. In this membrane emulsification device, the continuous phase kept in motion creates the shear stress at the membrane surface that detaches the forming droplets. In a different operation mode, that is, when the continuous phase is not stirred, droplet formation in quiescent conditions is obtained. 

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