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Density parameters

Adesina [14] considered the four main types of reactions for variable density conditions. It was shown that if the sums of the orders of the reactants and products are the same, then the OTP path is independent of the density parameter, implying that the ideal reactor size would be the same as no change in density. The optimal rate behavior with respect to T and the optimal temperature progression (T p ) have important roles in the design and operation of reactors performing reversible, exothermic reactions. Examples include the oxidation of SO2 to SO3 and the synthesis of NH3 and methanol CH3OH. [Pg.543]

According to Manning s theory [43-45], a polyion is characterized by a dimensionless charge density parameter B, which is defined by... [Pg.57]

Average axial spacing in A between charged groups on the polyion b Charge density parameter calculated from Eq. 5 using the dielectric constant of bulk water (e = 78)... [Pg.59]

Manning s theory does not take the local effective dielectric constant into consideration, but simply uses the a value of bulk water for the calculation of E,. However, since counterion condensation is supposed to take place on the surface of polyions. Manning s 2, should be modified to E, by replacing a with aeff. The modified parameters E, is compared with E, in Table 1, which leads to the conclusion that the linear charge density parameter calculated with the bulk dielectric constant considerably underestimates the correct one corresponding to the interfacial dielectric constant. [Pg.60]

Fig. 4. Relationship between the electrostatic potential calculated from the PB equation and the charge density parameter at distances 5,10, and 15 A from the axis of a cylinder with 3 A radius. Points indicate experimental data listed in Table 1 [42]... Fig. 4. Relationship between the electrostatic potential calculated from the PB equation and the charge density parameter at distances 5,10, and 15 A from the axis of a cylinder with 3 A radius. Points indicate experimental data listed in Table 1 [42]...
The first parameter, which indicates how densely the atoms are packed, will be denoted by D here since it may be called the Density parameter . It should be proportional to the number density (= number of atoms in a unit volume) but must be independent of the size of the atoms, depending only on the relative... [Pg.30]

The DE were determined by titrimetry, and the galacturonic acid (GalA) content was measured by the m-hydroxybiphenyl method [25]. The structural charge density parameter introduced by Lifson and Katchalsky [26], is given by = e2/bDkT(l-DE/100) were e is the electron charge, kT the Boltzman term, b... [Pg.36]

For a univalent counterion the charge density parameter X was found to be A = 1.551a where a value of 7 = 1.06 was employed because of the degree of esterification of the methyl ester of PGA ( 5.34 per cent). A comparison of calculated and experimental values of i,pK -pKl) at different degrees of dissociation is shown in Fig. 2. For pK the values from Table 2 were used. [Pg.616]

Cohesive energy (or free energy) density parameter (Chaps. XII and XIII). [Pg.640]

Pichon-Pesme, V., Lecomte, C. and Lachekar, H. (1995) On building a data bank of transferable experimental electron density parameters application to polypeptides, J. Phys. Chem., 99(16), 6242-6250. [Pg.35]

Fig. 1. The baryon density parameter, r/10, inferred from SBBN and the relic abundances of D, 3He, 4He, and 7Li (filled circles), along with the non-BBN determination from WMAP (filled triangle). See the text for details. Fig. 1. The baryon density parameter, r/10, inferred from SBBN and the relic abundances of D, 3He, 4He, and 7Li (filled circles), along with the non-BBN determination from WMAP (filled triangle). See the text for details.
After e annihilation during the early evolution of the Universe, the ratio of baryons to photons is, to a very good approximation, preserved down to the present. The baryon density parameter is defined to be this ratio (at present) r] = n /n r/io =... [Pg.333]

The true density of a solid is the average mass per unit volume, exclusive of all voids that are not a fundamental part of the molecular packing arrangement [55]. This density parameter is normally measured by helium pycnometiy, where the volume occupied by a known mass of powder is determined by measuring the volume of gas displaced by the powder. The true density of a solid is an intrinsic property characteristic of the analyte, and it is determined by the composition of the unit cell. [Pg.21]

Volumes of activation can be unambiguously determined only from the pressure dependence of the rate constants. Attempts to obtain volumes of activation from the correlation of rate constants with the solubility parameter 22 or the cohesive energy density parameter (ced)23, which are related to the internal pressure of solvents, have not led to clear-cut results. [Pg.549]

Because of the destruction of D when interstellar gas is recycled through stars, its present-day abundance is a firm lower limit to the primordial one. Adopting the local bubble value as representative of the Galaxy places an upper limit on the baryonic density parameter,... [Pg.132]

If the incoming call distribution is Poisson, and the time to service a call has an exponential distribution (Eq. 11 with density parameter p), then the transitional probabilities related to states s0 (the server is free) and Si (the server is engaged) are Pio= 1 - exp(-pt) poi = 1 -pw> pu= 1 -P o, Pooandpu are found by solving the Kolmogorov equations (Eq. 8)... [Pg.289]

An electrolytic plant (e.g., a metal refinery) may operate m number of cells which have to be taken out of service temporarily at regular time intervals. The probability that a cell is being put back into service within a small At time period is /.At, where X is the density parameter. The probability that a cell is taken out of operation within At is uAt. and 11 is the second density parameter. The limiting probabilities pt j = 0,1,2..., m of exactly j number of cells being switched back into operation can be obtained by a procedure identical to the electrical power line/machine operation problem stated by Rozanov5 (Problem 9, p. 114) and Sveshnikov6 (Problem 39.16, pp. 255-256 455) ... [Pg.305]

C is a universal constant (calculable from the model) and r is the density parameter equal to r = (3/4 7T)1/3 (V[N t )J,/3 V is the volume of the unit cell which contains Adatoms, and each atom contributes v free valence electrons to the collective motion. Because the actual crystal structure is disregarded, only one value of 7 is obtained for each metal. For lithium, for instance, 7 seems to be 490 erg/cm2 and... [Pg.14]

The reason for this difference is very simple. It is that the density functional approach calculates the rate for the adiabatic channel. For AG x> this will proceed via an activated complex with successor-state formal electron density parameter A = 1 for AGq <-x, it will proceed via an activated... [Pg.304]

Given a confinement radius, R, the orbital density parameters are allowed to evolve freely until the total energy given by equation (19) becomes a minimum subject to the normalization constraint indicated in equations (27) and (30). An auxiliary condition for the free-case (R 00) is the fulfillment of the Virial... [Pg.347]


See other pages where Density parameters is mentioned: [Pg.402]    [Pg.193]    [Pg.761]    [Pg.274]    [Pg.59]    [Pg.31]    [Pg.32]    [Pg.165]    [Pg.218]    [Pg.341]    [Pg.123]    [Pg.287]    [Pg.288]    [Pg.302]    [Pg.303]    [Pg.306]    [Pg.319]    [Pg.320]    [Pg.334]    [Pg.335]    [Pg.338]    [Pg.30]    [Pg.304]    [Pg.3]    [Pg.231]    [Pg.231]    [Pg.237]    [Pg.237]   
See also in sourсe #XX -- [ Pg.30 ]




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Binary interaction density parameter

Calculation of Lattice-Gas Parameters by Density Functional Theory

Charge density flocculation parameters

Charge density parameter

Charge density parameter, cationic

Charge density parameter, cationic polyelectrolyte

Cohesive energy density parameter determinations

Cohesive energy density parameters

Density anomalies order parameter

Density parameter, definition

Density parameters, averages

Density paste, parameters

Density-based methods adjustable parameter

Density-based methods smoothing parameter

Design parameters density

Influence of Density on Detonation Parameters

Kinetic parameters density Tafel slope

Lattice Parameters and Density

Level density parameter

Metal surface charge density parameter

Nucleation population density parameter

Order parameter density

Polymer charge density, effect parameters

Ps states in condensed matter the contact density parameter

Solubility parameter and the cohesive energy density

Surface charge density parameter space

The parameters in a charge density refinement

Transferability of charge density parameters among related atoms

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