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Early theories

Introduction to Applied Colloid and Surface Chemistry, First Edition. Georgios M. Kontogeorgis and S0ren Kiil. 2016 John Wiley Sons, Ltd. Published 2016 by John Wiley Sons, Ltd. [Pg.321]

This equation is also quite successful for many metal-metal systems (see references in Good, 1977). [Pg.322]

GG tried to estimate the correction p parameter from molecular properties (dipole moments, polarizabilities and ionization potentials) but this has been only partially successful. Such predictive approaches yield, for example, for water-benzene a correction factor equal to 0.55 (while the experimental correction value is 0.74) and 0.96 for watcr-mitrobenzene (experimental value is 0.80) (Good, 1992). Thus, there are both under- and overestimafions of the experimental correction parameter of the GG equation using these predictive approaches. [Pg.322]

As discussed in Chapter 6, the use of the GG equation together with Young s equation yields (if the correction p parameter is equal to one)  [Pg.322]

Is this equation really in disagreement with the Zis-man plot Equation 15.2 implies that the cosine of the contact angle is proportional to the inverse of the square root of the liquid surface tension instead of the liquid surface tension, indicated by the Zisman plot. The difference is only apparent. Good (1992) expands Equation 15.2 using a Taylor series expansion and he obtains  [Pg.322]


In two classic papers [18, 46], Calm and Flilliard developed a field theoretic extension of early theories of micleation by considering a spatially inliomogeneous system. Their free energy fiinctional, equations (A3.3.52). has already been discussed at length in section A3.3.3. They considered a two-component incompressible fluid. The square gradient approximation implied a slow variation of the concentration on the... [Pg.754]

A fiill theory of micleation requires a dynamical description. In the late 1960s, the early theories of homogeneous micleation were generalized and made rigorous by Langer [47]. Here one starts with an appropriate Fokker-Planck... [Pg.755]

In their more familiarly written form NO(OH)2+ = H2N03+ and N(OH)3++ = H3N03++ are respectively the nitracidium and hydronitracidium ions. For further discussion of early theories of species existing in MA the reader is referred to Urbanski (Ref 74, pp 12—14). Modern concepts will be examined in detail in Section VIII... [Pg.225]

In a review of the subject, Ubbelohde [3] points out that there is only a relatively small amount of data available concerning the properties of solids and also of the (product) liquids in the immediate vicinity of the melting point. In an early theory of melting, Lindemann [4] considered that when the amplitude of the vibrational displacements of the atoms of a particular solid increased with temperature to the point of attainment of a particular fraction (possibly 10%) of the lattice spacing, their mutual influences resulted in a loss of stability. The Lennard-Jones—Devonshire [5] theory considers the energy requirement for interchange of lattice constituents between occupation of site and interstitial positions. Subsequent developments of both these models, and, indeed, the numerous contributions in the field, are discussed in Ubbelohde s book [3]. [Pg.2]

Early theories of the biological effects of ethanol were based on alterations of lipids in biomembranes (Goldstein et al. 1983 Seeman 1972). Such a nonspecific mechanism provided little guidance for the development of therapeu-... [Pg.9]

Early theories of Guth, Kuhn, Wall and others proceeded on the assumption that the microscopic distribution of end-to-end vectors of the chains should reflect the macroscopic dimensions of the specimen, i.e., that the chain vectors should be affine in the strain. The pivotal theory of James and Guth (1947), put forward subsequently, addressed a network of Gaussian chains free of all interactions with one another, the integrity of the chains which precludes one from the space occupied by another being deliberately left out of account. Hypothetical networks of this kind came to be known later as phantom networks (Flory, 1964,... [Pg.586]

First, we want to make a comment about possible local temperature rise due to energy absorption. An early theory of radiation effect s was based on the point-heat hypothesis (Dessauer, 1923). Later analysis showed that the temperature rise would be too feeble and too transient for low-LET radiation to cause any real change (see Mozumder, 1969). There is no experimental evidence for temperature rise for low-LET radiations. The case of high-LET radiations is still open, though. [Pg.263]

An early theory of ionic recombination in liquids was developed by Jaffe (1913) for application at a relatively high LET. However, in Jaffe s theory, coulombic interactions are ignored and the positive and negative ions are assigned the same mobilities and distribution functions. Therefore, its use in a... [Pg.297]

Most early theories were concerned with adsorption from the gas phase. Sufficient was known about the behaviour of ideal gases for relatively simple mechanisms to be postulated, and for equations relating concentrations in gaseous and adsorbed phases to be proposed. At very low concentrations the molecules adsorbed are widely spaced over the adsorbent surface so that one molecule has no influence on another. For these limiting conditions it is reasonable to assume that the concentration in one phase is proportional to the concentration in the other, that is ... [Pg.980]

In much of the early theory used to describe adsorption in different kinds of equipment, it was assumed that equilibrium was achieved instantly between the concentrations of adsorbate in the fluid and in the adsorbed phases. Whilst it may be useful to make this assumption because it leads to relatively straightforward solutions and shows the interrelationship between system parameters, it is seldom true in practice. In large-scale plant particularly, performance may fall well short of that predicted by the equilibrium theory. [Pg.1002]

The nature, or more precisely the structure, of a particular turbulent flame implied by these inequalities cannot be exactly established at this time. The reason is that values of <5L, Zk, A, or Z0 cannot be explicitly measured under a given flow condition or analytically estimated. Many of the early experiments with turbulent flames appear to have operated under the condition flow conditions under which <5L would indeed be less than Zk has been explored analytically in detail and will be discussed subsequently. [Pg.221]

Early theories of electron transfer attempted to give a theoretical foundation to the phenomenological rate expression (Eq. 15) and the constants A, a, and o. A brief summary of the history and references to recent reviews have recently been given by Marcus. " Marcus theory has been able to derive an expression similar to Eq. (15), in which the relationship between the activation free energy and the reaction free energy is given in terms of a new quantity called the reorganization free... [Pg.155]

Grotthus chain theory phys chem An early theory used to explain the conductivity of an electrolyte. In which it was assumed that the cathode and anode attract hydrogen and oxygen respectively, and the molecules of the electrolyte are stretched out In chains between the electrodes, with decomposition occurring in molecules closest to the electrodes. grot-hus chan, the-3-re group CHEM I.Afamllyofelementswithsimilarchemical properties. 2. Acombina-tlon of bonded atoms that behave as a unit under certain conditions, for example. [Pg.171]

Ringbom, S. Art in the Epoch of the Great Spiritual Occult Elements in the Early Theory of Abstract Painting. Journal of the Warburg and CourtauM Institutes 29 (1961) 386-H8. [Pg.450]

An early theory of the IT value was proffered by Spencer and Fano [44], based on the degradation spectrum. Another method, the Fowler equation, was employed by Inokuti [47] for electron irradiation, based on the approximation that there is only one ionization potential and that the ionization efficiency is unity. These restrictions can be relaxed. The main result of Inokuti s analysis may be given as follows. [Pg.26]

Before leaving SD applications of the LRA, it is worth stressing that a different approach has often been taken in relating the electrostatic C i) to pine solvent dynamics. In this approach, the connection is made to solvent dielectric relaxation. Early theories made the connection through the longitudinal dielectric relaxation time," while more recent ones use as input the dielectric dispersion s or its generalization to finite wavevectors, e(k, co). 23.24.29,68,89... [Pg.225]

Birth of Dr. John Mayow in London. Author of an early theory of combustion. [Pg.886]

Early theories of elution chromatography developed by Wilson, Glueckauf, De Vault " and others, established the found-... [Pg.184]


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See also in sourсe #XX -- [ Pg.45 , Pg.202 , Pg.203 , Pg.204 , Pg.205 ]

See also in sourсe #XX -- [ Pg.210 , Pg.211 , Pg.212 , Pg.213 , Pg.214 ]




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