Let us consider a closed path L defined in terms of a continuous parameter X so that the starting point sg of the contour is at 1 = 0. Next, P is defined as the value attained by X once the contour completes a full cycle and returns to its starting point. For example, in the case of a circle, X is an angle and P = 2tu. [Pg.646]

We will use it here in order to derive an analytical form for a crystal profile with a rough interface as an exphcit example. An order parameter

crystalline phase with 0 > 0 and the gaseous (or hquid) one with 0 < 0. [Pg.878]

P ) Qpp- The specification of P and the solid flow rate (or, alternatively, one of the liquid flow rates) defines all the flow rates throughout the TMB system. The P parameter has a higher limit, since the feed flow rate must be higher than zero, 1 < /3 < v t. The case of /3 = 1 corresponds to the situation where dilution of species is minimal, and the extract and raffinate product concentrations approach the feed concentrations. In fact, for /3 = 1, we obtain = Qf = = ( - 1) = (Kg... [Pg.232]

elementary charge, T the absolute temperature, k the Boltzmann constant, and x the Debye screening parameter defined by x = (8jtne2/skT)1/2. [Pg.56]

In the present study, we carried out the hydrogenation of CO2. We did not use any inert components in the feed. We changed the value of r by changing the molar ratio of H2 to CO2 in the feed gases, a. The parameter p is defined as the volume ratio of the product gas to the reactant gas when the reaction completely proceeds under a constant pressure. The extent of the gas-volume reduction is affected by the stoichiometric relation of the reaction and the content of the inert components in the feed. As given in Eq.(l), p is the function of only the parameter a and the expression of p is affected by a. When a > 4, the limiting reactant is H2, while it is CO2 in the case of a < 4. [Pg.498]

A general definition of log P and log D, in its simplest form, can be given as the logarithm of the ratio (P or D) of the concentration of species of interest (the drug in a pharmaceutical context) in each phase, assuming the phases are immiscible and well separated prior to analysis. P is defined as the partition coefficient, whereas D is the distribution coefficient. However, the simplest form does not reveal some of the intricacies of the determination and use of these parameters, and further explanation is necessary. [Pg.408]

Note that the lipophilicity parameter log P is defined as a decimal logarithm. The parabolic equation is only non-linear in the variable log P, but is linear in the coefficients. Hence, it can be solved by multiple linear regression (see Section 10.8). The bilinear equation, however, is non-linear in both the variable P and the coefficients, and can only be solved by means of non-linear regression techniques (see Chapter 11). It is approximately linear with a positive slope (/ ,) for small values of log P, while it is also approximately linear with a negative slope b + b for large values of log P. The term bilinear is used in this context to indicate that the QSAR model can be resolved into two linear relations for small and for large values of P, respectively. This definition differs from the one which has been introduced in the context of principal components analysis in Chapter 17. [Pg.390]

Seiler [250] proposed a way of estimating the extent of hydrogen bonding in solute partitioning between water and a lipid phase by measuring the so-called A log P parameter. The latter parameter is usually defined as the difference between the partition coefficient of a solute measured in the octanol-water system and that measured in an inert alkane-water suspension AlogP = log Kp oet — log Kp aik. [Pg.224]

Irrespectively of the iron content, the applied synthesis procedure yielded highly crystalline microporous products i.e. the Fe-ZSM-22 zeolite. No contamination with other microporous phases or unreacted amorphous material was detected. The SEM analysis revealed that size and morphology of the crystals depended on the Si/Fe ratio. The ZSM-22 samples poor in Fe (Si/Fe=150) consisted of rice-like isolated crystals up to 5 p. On the other hand the preparation with a high iron content (Fe=27, 36) consisted of agglomerates of very small (<0.5 p) poorly defined crystals. The incorporation of Fe3+ into the framework positions was confirmed by XRD - an increase of the unit cell parameters with the increase in the number of the Fe atoms introduced into the framework was observed, and by IR - the Si-OH-Fe band at 3620 cm 1 appeared in the spectra of activated Fe-TON samples. [Pg.114]

P-parameter of the smallest value defines the orbital that is mainly responsible for isomorphism. [Pg.96]

However, a strictly defined model of such system formation does not currently exist. To further study the problem of nanostructure phase-formation the methodology of P-parameter is applied in this paper. [Pg.208]

Further let s consider the question, which parameters define the value a and, hence, the active time value f. As it is known [5], the relation a/p is connected with exponent p at / in the generalized transport equation as follows ... [Pg.245]

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