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Relative total volume: defined

It is necessary to find the appropriate solvent for the given solute and the optimum temperature and pressure conditions for instantaneous crystallization of the solute from its solution, at which the antisolvent, CO2 either is totally miscible in the solvent or has a very high solubility in it. The solvent and CO2 are completely miscible as the binary mixture reaches the mixture critical point. There is an exponential increase in the total volume of the solution with increasing dissolution of CO2. Originally, the relative total volume expansion (RTVE) of the solvent was the criterion for the GAS crystallization, which was defined (45) as... [Pg.59]

Depending on the particular method of polymer HPLC, is defined in different ways. It is the total volume of pores, Vp, in a porous packing but it can be also related to the total surface of packing (mostly to the surface situated within the pores) or to the effective volume of bonded phase. The volume of pores is relatively well defined in the case of many packings applied in polymer HPLC and plays an especially important role in the exclusion-based separations (Sections 16.3.3, 16.3.4, and 16.4.1). The exclusion processes, however, play an important role in the coupled techniques of polymer HPLC (Section 16.5). In the latter cases, the surface of packings and the effective volume of bonded phase are to be taken into account. In some theoretical approaches also, surface exclusion is considered. [Pg.455]

Another relatively simple measure for characterizing texture that is suggested in the polymer processing literature is the striation thickness, which is defined as the total volume divided by one-half the total interfacial surface (10)... [Pg.389]

The best possible mode of gas-liquid contact for a given process depends upon a combination of effects, including hydrodynamics, mass transfer, and chemical kinetics. In treating this combination, a dimensionless parameter P has been defined as the ratio of total volume of the liquid phase to volume of the liquid diffusion layer. Krishna and Sie reported general values of jS to be 10 0 for thin liquid films and liquid sprays, and 10 -10" for gas bubbles within a continuous liquid. The relative rates of mass transfer and chemical reaction show whether high values or low values of jS best utilize available reactor volume. [Pg.1119]

Micellar electrokinetic chromatography (MEKC) is a particular EKC mode where the secondary phase is composed by micellized surfactant (MEKC is discussed in detail in Chapter 3 by Terabe). Solute differential retention occurs as a result of a partition mechanism between a dispersed phase defined by the total volume of micelles and the remaining aqueous phase. MEKC modes of elution comprise normal, restricted, and reversed MEKC, based on the relative migration of the analyte and secondary phase apparent velocity. [Pg.915]

The second relation is valid for all values of rg and Yg considered to be continuously distributed within their total definition ranges. We note that the segment number Tb is defined here as the ratio of the molar volumes of the block copolymer and the solvent (i.e. r = 1) and that the chemical composition Yb is defined here as the volume fraction of the a-blocks relative to the total volume of all a- and P-blocks in the copolymer. [Pg.103]

A deterministic objective function is chosen for the optimization problem, and it corresponds to the total volume of the column elements. To control serviceability and minor damage, the design criterion considered in this example problem is defined in terms of the interstory drift ratio in the x and y direction over all stories of the building, and the relative rotation between consecutive floors. Therefore, the number of response functions involved in the problem is 18 and the system failure event F is defined as... [Pg.574]

The normalization factor (p signifies the relative range of influence of each force point. For a cyhnder with diameter D and height H, q> is defined as the volume per force point divided by the total volume of a grid cell... [Pg.198]

The phenomenon of glass transition in polymers is best analyzed by applying the concept of free volume. It is observed that for a variety of polymers the fractional free volume (defined as the ratio of free volume and total volume) in the glassy state (fg) is relatively constant. Fractional free volume at a temperature T (above is given by... [Pg.13]

If the total volume of pores having radii between r and r-t-6r is dV, the relative pore frequency by volume is defined by ... [Pg.166]

These profiles may be defined by the following equations, where V is the total volume of the solution to be dosed and is the rate of dosage at any time t. The total volume of the solution that has to be dosed together with the total dosing time determines the constants a, b and c in the pre-set dosing profiles. However, one of the main shortcomings of this system is that these eonstants need to be known for each profile and each of the various solutions that may be nsed therefore, a relatively large database would be required. [Pg.183]

The dimensionless parameters that define the thermodynamic state of this system are the total volume fraction ( ) = (nl6)n (with n being the total number concentration, n = n, + n, the relative concentrations = njn, and the potential parameters K2, and z. The free-diffusion coefficients D° are also assumed identical for both species, that is, D = D = D°. Explicit values of the parameters a and D are not needed, since the dimensionless dynamic properties, such as t), only depend on the dimensionless parameters specified above, when expressed in terms of the scaled variables ka and t/to, where to = a /D . Besides solving the SCGLE scheme, in reference [21] Brownian dynamics simulations were generated for the static and dynamic properties of the system above. [Pg.17]

Naturally Derived Materials. The following are descriptions of some of the most important naturally derived materials in use. Importance in this context is defined in terms of the total value of the materials, which range from expensive, low volume materials that have great aesthetic value to relatively inexpensive and widely used products. Eor some of the naturals, it is indicated whether they can be distilled to provide individual chemicals for use as such or as intermediates. Materials produced in this way from a given natural source are usually not interchangeable with those from other naturals or synthetics. In some cases this may be due to optical isomerism, which can have a significant effect on odor, but usually it is due to trace impurities. [Pg.76]

Figure 28 shows the key features of the humidity chart. The chart consists of the following four parameters plotted as ordinates against temperature on the abscissas (1) Humidity H, as pounds of water per pound of dry air, for air of various relative humidities (2) Specific volume, as cubic feet of dry air per pound of dry air (3) Saturated volume in units of cubic feet of saturated mixture per pound of dry air and (4) latent heat of vaporization (r) in units of Btu per pound of water vaporized. The chart also shows plotted hiunid heat (s) as abscissa versus the humidity (H) as ordinates, and adiabatic humidification curves (i.e., humidity versus temperature). Figure 28 represents mixtures of dry air and water vapor, whereby the total pressure of the mixture is taken as normal barometric. Defining the actual pressure of the water vapor in the mixture as p (in units of mm of mercury), the pressure of the dry air is simply 760 - p. The molal ratio of water vapor to air is p/(760-p), and hence the mass ratio is ... [Pg.128]


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See also in sourсe #XX -- [ Pg.274 ]




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