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Lattice enhancement

Structure and isomorphous substitution within the crystal lattice enhances this effect. Isomorphous substitution leaves one negative charge unsatisfied. Because this charge originates from within the lattice, it is permanent in nature, and depending on its magnitude, it will strongly influence the metal adsorptive capacity of the clay particle. [Pg.479]

Measurement of spin-lattice enhancement in water and plasma solution An measured in 16 solvents. Plot of vs. dielectric constant parameter... [Pg.326]

Cu-doped ceria is a good candidate for catalytic combustion. The incorporadon of Cu species into the CeO lattice enhances its OSC and redox property by decreasing the activadon energy to much lower temperatures for the reducdon of Ce, as revealed by the invesdgadons of Hu et Their study discovered that Ceo svCuq isOy... [Pg.436]

If adsorption occurs via a physisorbed precursor, then the sticking probability at low coverages will be enhanced due to the ability of the precursor to diflfiise and find a lattice site [30]. The details depend on parameters such as strength of the lateral interactions between the adsorbates and the relative rates of desorption and reaction of the precursor. In figure Al.7,8 an example of a plot of S versus 0 for precursor mediated adsorption is presented. [Pg.298]

If the simulated system uses periodic boundary conditions, the logical long-range interaction includes a lattice sum over all particles with all their images. Apart from some obvious and resolvable corrections for self-energy and for image interaction between excluded pairs, the question has been raised if one really wishes to enhance the effect of the artificial boundary conditions by including lattice sums. The effect of the periodic conditions should at least be evaluated by simulation with different box sizes or by continuum corrections, if applicable (see below). [Pg.9]

In a second attempt to obtain more insight into the binding location of the dienophile and now also the diene, we have made use of the influence of paramagnetic ions on the spin-lattice relaxation rates of species in their proximity. Qose to these ions the spin-lattice relaxation rate is dramatically enhanced. This effect is highly distance-dependent as is expressed by Equation 5.7, describing the spin-lattice... [Pg.146]

Calculations of the interaction energy in very fine pores are based on one or other of the standard expressions for the pair-wise interaction between atoms, already dealt with in Chapter 1. Anderson and Horlock, for example, used the Kirkwood-Miiller formulation in their calculations for argon adsorbed in slit-shaped pores of active magnesium oxide. They found that maximum enhancement of potential occurred in a pore of width 4-4 A, where its numerical value was 3-2kcalmol , as compared with 1-12, 1-0 and 1-07 kcal mol for positions over a cation, an anion and the centre of a lattice ceil, respectively, on a freely exposed (100) surface of magnesium oxide. [Pg.207]

The active site on the surface of selective propylene ammoxidation catalyst contains three critical functionalities associated with the specific metal components of the catalyst (37—39) an a-H abstraction component such as Sb ", or Te" " an olefin chemisorption and oxygen or nitrogen insertion component such as Mo " or and a redox couple such as Fe " /Fe " or Ce " /Ce" " to enhance transfer of lattice oxygen between the bulk and surface... [Pg.183]

The main contribution to the spin-lattice relaxation of C nuclei which are connected to hydrogen is provided by the dipole-dipole interaction (DD mechanism, dipolar relaxation). For such C nuclei a nuclear Overhauser enhancement of almost 2 will be observed during H broadband decoupling according to ... [Pg.65]

These observations consummated in a growth model that confers on the millions of aligned zone 1 nanotubes the role of field emitters, a role they play so effectively that they are the dominant source of electron injection into the plasma. In response, the plasma structure, in which current flow becomes concentrated above zone 1, enhances and sustains the growth of the field emission source —that is, zone 1 nanotubes. A convection cell is set up in order to allow the inert helium gas, which is swept down by collisions with carbon ions toward zone 1, to return to the plasma. The helium flow carries unreacted carbon feedstock out of zone 1, where it can add to the growing zone 2 nanotubes. In the model, it is the size and spacing of these convection cells in the plasma that determine the spacing of the zone 1 columns in a hexagonal lattice. [Pg.12]


See other pages where Lattice enhancement is mentioned: [Pg.44]    [Pg.166]    [Pg.14]    [Pg.100]    [Pg.132]    [Pg.215]    [Pg.17]    [Pg.147]    [Pg.54]    [Pg.25]    [Pg.89]    [Pg.44]    [Pg.44]    [Pg.166]    [Pg.14]    [Pg.100]    [Pg.132]    [Pg.215]    [Pg.17]    [Pg.147]    [Pg.54]    [Pg.25]    [Pg.89]    [Pg.44]    [Pg.2931]    [Pg.2937]    [Pg.16]    [Pg.480]    [Pg.160]    [Pg.168]    [Pg.178]    [Pg.447]    [Pg.367]    [Pg.521]    [Pg.53]    [Pg.200]    [Pg.255]    [Pg.245]    [Pg.469]    [Pg.65]    [Pg.245]    [Pg.90]    [Pg.192]    [Pg.142]    [Pg.416]    [Pg.632]    [Pg.641]    [Pg.44]    [Pg.168]    [Pg.314]    [Pg.183]    [Pg.1042]    [Pg.761]   
See also in sourсe #XX -- [ Pg.559 ]




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