Salient conclusions

Hydrodynamics, mass, and heat transfer in the commonly used three-phase fixed-bed reactors were briefly outlined. Also, scale-up rules and alternative ways to scale down trickle-bed reactors are discussed. In spite of the extensive studies on the hydrodynamics, mass, and heat transfer in three-phase fixed-bed reactors, clearly, a lot of work remains to be done in providing a fundamentally based description of the effect of pressure on the parameters of importance in three-phase fixed-bed reactors operation, design, and scale-up or scale-down. It is evident that atmospheric data and models/correlations cannot, in general, be extrapolated to operation at elevated pressures. The physics conveyed by the standard two-phase flow models is minimalistic because it insufficiently describes the role and presence of interfaces and their thermodynamic properties. The explicit inclusion of interfaces and interfacial properties is essential because they are known to have a significant role in determining the thermodynamic state of the whole system. 

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Reduction of ketones to triphenylsilyl ethers is effected by the unique Lewis acid perfluorotriphenylborane. Mechanistic and kinetic studies have provided considerable insight into the mechanism of this reaction.186 The salient conclusion is that the hydride is delivered from a borohydride ion, not directly from the silane. Although the borane forms a Lewis acid-base complex with the ketone, its key function is in delivery of the hydride. 

The following are the salient conclusions resulting from this study. 

Although the data are not as complete for the other lanthanides, it is possible to give the approximate ranges of t2 which span the values assumed by this parameter in the systems which have been investigated up to now. The range of T2-values for solution and vapor spectra of the lanthanides based on the best currently available data are listed in Table XI. The salient conclusions to be drawn from this survey are that t2 has experimentally been found to vary by as much as a factor of 100 and that the largest values of t2 occur in the tribromide and triiodide vapor spectra. 

Benthic fluxes of Mn and reprecipitation are known to influence the spatial distribution of solid-phase Mn within near-shore basins (Evans et al., 1977 Grill, 1978). These fluxes may also influence the distribution of Mn within the ocean basins as a whole. For example, Turekian (1977) calculated that if the annual Mn flux found in LIS ( 1 mmole/mVyr) were assumed to apply to 1% of the sea floor and if a few percent of this annual flux were lost to the deep sea, then the excess Mn accumulation rate of 1 p,g/cmVyr (Bender el al., 1970 Eldeifield, 1976) in deep-sea sediments could be accounted for. The salient conclusion is not necessarily that near-shore sediment-water Mn fluxes cause excess Mn accumulation in the deep sea but that these fluxes can be high enough to affect large-scale distributions. 

The following salient conclusions emerge from the present work ... 

SHG was used to monitor the polar alignment that was indueed in these systems. Values of the seeond-order NLO coefficients fi 3 and 33 are given in Table 23. The salient conclusions of the results are as follows ... 

The ability to fluorescently tag individual DNA molecules and visualize their dynamics in these flows can considerably enhance the information we obtain from these flows. Numerous single molecule visualization experiments have already led to significant advancements in our understanding of polymer chain dynamics in viscous flows. In addition, these experiments have recently been combined with Brownian dynamics simulations, which simulate the motion of bead-rod chains in viscous flows and can quantitatively predict the chain conformation for given flow conditions. This powerful combination has allowed for the validation of detailed molecular scale physics, as well as the development of new physical insights. These conclusions are described in a recent review [10] we summarize a few of the salient conclusions here. 

For other values oi 6e-> the formula is similar but more complicated (see ref. 4 for the case 6e l)-" The salient conclusions are as follows ... 

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