Dispersion-induced

Table III shows that both cobalt and arsenic affect the Mo/Al ratio as measured by XFS. These elements cause the Mo/Al ratio on both calcined and sulfided catalysts to decrease. Again this is due either to covering of molybdenum by promoters or more likely to some change in molybdenum dispersion Induced by the promoters.

Yoshida, Y. and Niki, E. (1992). Oxidation of methyl linoleate in aqueous dispersions induced by copper and iron. Arch. Biochem. Biophys. 295, 107-114. 

The major forms of van der Waals forces between molecules that are not bonded together are the permanent dipole-dipole interaction, the dispersion-induced temporary dipole interaction, and the hydrogen bond. They are short-range forces that operate only when two atoms or molecules are in close proximity. The Lennard-Jones potential of 6-12 is a model of this potential field ... 

While exchange- and dispersion-induced dipole components are of a quantum nature, the multipole-induced dipole components can be modeled by classical relationships, if the quantum effects are small. For many systems of practical interest, multipolar induction generates the dominant dipole components. The classical multipole induction approximation has been very successful, except for the weakly polarizable partners (e.g., He atoms) [193]. It models the dipole induced in the collisional partner by polarization in the molecular multipole fields. 

Arakane, K., Hayashi, K., Naito, N., Nagano, T., and Hirobe, M. (1995) pH lowering in liposomal dispersions induced by phospholipid peroxidatio6hem. Pharm. Bull., 43 1755-1758. 

H. Huang, E. Ruckenstein Thermodynamically stable dispersions induced by depletion interactions JOURNAL OF COLLOID AND INTERFACE SCIENCE 290 (2005) 336-342. 

Thermodynamically stable dispersions induced by depletion interactions... 

Many processes in soil are controlled by colloid flocculation or dispersion. One such process is hydraulic conductivity. The data in Figure 10.3 show that for a Mg2+-saturated soil containing a solution of 3.16 x 10 2 M MgCl2, its hydraulic conductivity decreased by 35% after 5 hr of leaching with distilled water (Quirk and Schofield, 1955). This demonstrates that as solution ionic strength approaches zero, soil hydraulic conductivity decreases significantly owing to soil dispersion induced by a decompressed electric double layer. 

Most food systems are of a colloidal as well as a polymeric nature. The presence of a nonadsorbing polymer in a skim milk dispersion induces an effective attraction between the casein particles, called depletion interaction, resulting in phase separation at sufficiently high polymer concentration. Tuinier et al. (2003) discussed the influence of colloid-polymer size ratio, polymer concentration regime, size, poly-dispersity and charges in colloid/biopolymer mixtures, demonstrating the challenging complexity of the subject. 

TThe subscript A indicates the dispersion coefficient used for the layer which describes the dispersion induced by the apparatus. 

Even though the components of the total interaction potential between such complex adsorbents as solid carbons and a wide range of adsorbates can be grouped in many different ways 315,316], it is convenient and meaningful to consider only the London dispersion (induced dipole) forces and the electrostatic (double-layer) forces [620,621,76,77]. 

Ice samples have a main dispersion induced by reorientation of the water molecules and proton conduction with movement of the point defects. Here, we discuss values of the relaxation time r of the main dispersion of ice samples reported in the literature and measured by the present authors. For convenience in experimental measurements, we define two classification of ice sample as bulk ice and ice particle aggregates corresponding to two types of growth, liquid phase growth and vapor phase growth. 

Iron oxide dispersion-induced micropore filling of supercritical NO... 

Basic oxide—dispersion induced enhancement of micropore iilling of CH4... 

Sodium carboxymethyl cellulose (CMC, cellulose gum) is an anionic, water-soluble polymer (Figure 5.13). It is stable in a pH range of 4 to 10 and is compatible with most monovalent and divalent salts, as well as most anionic and nonionic materials. However, it is generally incompatible with cationic species due to its anionic nature. The structural stability of dispersions induced by CMC is highly dependent upon the concentration of the polymer. CMC is used as a thickener in toothpastes, skin creams, lotions, and food applications. The degree of... 

The validity of the direct substitution for Ay into the first-order expression for the CD of electric dipole allowed transitions is verified readily using, for example, a simple vibronic coupling model. The procedure is analogous to that discussed elsewhere for vibronic contributions to DICD (dispersion (dispersion-induced CD)(14). As Ay is, in itself, first-order in the vibronic perturbation, the CD strength of the d-d trans- ... 

We stress that all the approaches presented in this subsection, leading to normal and anomalous diffusion, are intended to model dispersion. As clearly seen in (2.28) and their equivalents for anomalous diffusion these equations damp the higher Fourier modes so that there is a relative increase of variance at larger scales. But in situations such as in modelling dispersion induced by turbulent flows the dispersion is a consequence of the stretching of fluid elements that is associated with compression along the complementary directions. This produces a direct cascade of variance towards small scales that is not captured by the diffusion equation (2.9). Thus the small scale distribution and phenomena strongly dependent on this, like chemical reactivity, may not be adequately modelled in the framework of diffusion equations alone. 

FIGURE 6. Illustration of the hydrodynamic dispersivity induced by the variability of velocities within pores of different sizes, (a) Solute particles are released in variable flow field at time T. (b) Solute particles are observed at different location at time T + DT and generates a dilution of concentrations. 

J.H. Burnett, Z.H. Levine, E.L. Shirley, and J.H. Brunning, Symmetry of spatial dispersion induced birefringence and its implications for Cap2 ultraviolet optics, J. Microlith. Microfab. Micro syst. 1(3), 213 224 (2002). 

Table 13.8 Spatial dispersion-induced birefringence of Cap2 at different UV wavelengths. ...

If the solid is a simple molecular substance the melting (or boiling) temperature depends upon the strength of dispersion (induced dipole/induced dipole) force between the molecules. 

White phosphorus, sulphur and chlorine all form simple molecular solids. The melting temperatures depend upon the strengths of their intermolecular forces which are dispersion (induced dipole/induced dipole) forces. The strength of this force depends upon the number of electrons in the molecule. 

Figure 5.16. Variation of the UV-vis spectra of the colloidal dispersions induced by the UV light irradiation. The dispersions were obtained by adding water into a THF solution of PEAPE/BP-AZ-CA (1 1, wt wt). Source From Deng et al., 2007.

The extent to which the resonance bandwidth analysis is susceptible to dispersion-induced errors has been considered and it has been established that serious errors may be inciured (> 1% in 5) under conditions where waves are damped exponentially in one wavelength [Williams and Williams, 1994],... 

Electroosmotic flow has emerged as a viable alternative transport mechanism to pressure-driven flow in column chromatography. Benefits include a plug-flow profile (reduced transaxial contributions to zone broadening) and a mobile phase velocity that is independent of the column length and particle size. The electroosmotic-driven flow is governed by the dielectric constant of the mobile phase, the zeta potential at the stationary phase/mobile phase interface, and the applied electric field. The efficiency obtainable is limited by double layer overlap or radial dispersion induced by inefficient heat dissipation. 

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