Coupling model explanation

Explanations of the frequency upshift were given by Ohno,236ab Orlandi et al.,236c and Mikami and Ito239 in terms of a vibronic coupling model. While the model was quantitatively successful, it did not give... 

A quantitative explanation of data based on the two-particle, exchange-coupled model can be attempted only when protons appear in the form of relatively well-isolated pairs, such as in water. The data recorded for partially deuterated water by Chatzidimitriou-Dreismann et al. [Chatzidimitriou-Dreis-mann 1997 (a)] (see Fig. 6) were interpreted by Karlsson [Karlsson 2003 (a)] in terms of reduced pair CS as given in Eq. (7). With a relative deuterium concentration Xn = Ce>/(ch + rr>), the probabilities for forming IIX), />20 and HDO molecules is phh = c2h,pdd = c2D and phd = 2 cr cd, respectively (for Xd = 0.5 one has p2H = 0.25, p2D = 0.25 and 2 ph Pd = 0.50, etc.). With reduction factors Jim for H - H pairs, Jdd for D-D pairs, and Jhd = 1 (no exchange correlation) for H - D pairs, the model predicts the cross section ratio... 

In the 8-phase of niobium hydride, NbHo.ei, the additional structure observed in both the A and E modes remained in the spectrum of NbHo.03 Do.57 and the coupling model was dismissed [54].An explanation in terms of minor structural differences between the neighbouring sites in this phase was favoured. The degree of detail that can be extracted from more complex materials than the simple metals is limited and the spectra of TbNiAI H, 4 and UNiAl H2.0 are cases in point [55]. 

The explanation by the Coupling Model of this property has been given in conjunction with its background in Section (i).5 already. It is unnecessary to repeat that here. 

The Coupling Model is consistent with all the properties and has fundamental support from quasielastic neutron scattering and simulations. However, the emphasis of the entire section is on the many properties of component dynamics in HAPB that deserve attention and alternative explanation by researchers in glass transition and polymer chain dynamics and viscoelasticity. This is because the new physics found in the segmental and chain dynamics of components in highly asymmetric polymer blends could possibly revolutionize the current understanding of polymer dynamics and viscoelasticity. 

The distributed reactivity model explanation for the biphasic rate behavior commonly observed for desorption of HOCs from soils is that the soft-carbon sorbed, or labile fraction of the contaminant desorbs readily and reversibly, whereas the hard-carbon sorbed, or resistant component is released much more slowly. The slow desorption step has been attributed to non-Fickian diffusion into a tightly-knit SOM, polymerization, or entrapment within the SOM matrix. The rate model found in comparative analyses to be the most appropriate for description of such behavior (17) is a two-phase release model which couples first-order rate equations for both the slow, resistant, and rapid, labile fractions, < >r (= 1- (j) ... 

We remark that the coupling-model predictions for contraction, i.e. 8>0, while reasonable at small AT, fit less well at large AT. This was attributed to finite cooling-rate effects, not accounted for in equation (92). Furthermore, the coupling-model predictions have not been compared with other experiments, e.g. memory effect, uniform heating through the transition, etc., and ultimate confirmation of the model awaits such quantitative comparison. The results presented above as an explanation of the x-effective paradox are encouraging. 

Theoretical models of the film viscosity lead to values about 10 times smaller than those often observed [113, 114]. It may be that the experimental phenomenology is not that supposed in derivations such as those of Eqs. rV-20 and IV-22. Alternatively, it may be that virtually all of the measured surface viscosity is developed in the substrate through its interactions with the film (note Fig. IV-3). Recent hydrodynamic calculations of shape transitions in lipid domains by Stone and McConnell indicate that the transition rate depends only on the subphase viscosity [115]. Brownian motion of lipid monolayer domains also follow a fluid mechanical model wherein the mobility is independent of film viscosity but depends on the viscosity of the subphase [116]. This contrasts with the supposition that there is little coupling between the monolayer and the subphase [117] complete explanation of the film viscosity remains unresolved. 

First, any analysis must be coupled with a technically correct interpretation of the equipment performance soundly rooted in the fundamentals of mass, heat, and momentum transfer rate processes and thermodynamics. Pseudotechnical explanations must not be substituted for sound fundamentals. Even when the development of a relational model is the goal of the analysis, the fundamentals must be at the forefront. 

It might be thought that electron-spin coupling provides an explanation of the characteristic two-ness of electrons in molecules. This is not so spin coupling is a kind of mnemonic device for the formulation of the electron-pair model, not an explanation of it. 

There are many published examples in which the coupling of two different materials leads to an increase in the photocatalytic activity. Many of them concern coupling and junctions between different nanopartides, considering also different topologies, like coupled and capped systems [72]. Tentative explanations based on possible heterojunction band profiles are given. However, in-depth analysis of the hetero junction band alignment, the physical structure of the junction, the role of (possible) interfadal traps and of spedfic catalytic properties of the material is still lacking. Some recently published models and concepts based on (nano)junction between different materials are briefly reviewed here. 

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