Reduced radial distribution peaks

Reduced Radial Distribution Peaks at Pt L/// Edge [Pt at 1%] (converted, phase shifted, with area multiplied by R2)... 

Reduced radial distribution function, or oxygen-oxygen pair correlation function g0Q(r), for H20(l) at 300 K X rays, solid line [61,62] X rays dashed line [63] neutron, dot-dashed line [64] neutron, gray line [65]. The peaks indicate a first (nearest)-neighbor, a second, and a third 0-0 distance at approx 2.9 A, 4.3 A, and 6.5 A, respectively. 

Fig. 3.8. Reduced radial distribution functions, G(r), of three synthetic hydroxyapatites containing 0%, 1.1%, 3.7% CO3, respectively. The inclusion of CO3 in the apatite structure results in distortion of the lattice, observed as the diminished intensity of G(r) with increasing r and the decreased resolution of certain G(r) peaks ...

In conventional gas electron diffraction experiments, an effusive beam is used in which vibrational levels of molecules are thermally populated and the width of a peak in a radial distribution curve is determined by thermally averaged mean amplitudes. When a molecular beam or a free jet is used, mean amplitudes could become small, since the contribution from the vibrationally excited levels is reduced significantly. As a consequence, sharper peaks are expected in the radial distribution curve, and the spatial resolution of the snapshot could be improved. However, it seems that the observed peaks in the radial distribution curve are considerably broad even though a molecular beam is used. There could be some reasons to have such broadened peaks in the radial distribution curve. 

A natural goal of simulation would be the computation of the relative probabilities of these various states. A more elementary task is to compute the radial distribution which gives the distribution of distance between atom pairs observed. The radial density function may be approximated from a histogram of all pan-distances observed in a long simulation. (There are 21 at each step, so the amount of data is helpfully increased, reducing the sampling error .) This distribution is displayed in Fig. 3.5. The peaks of the radial distribution function are correlated with the various interatomic distances that appear in the cluster configurations shown in Fig. 3.4. 

The maximum-to-average fuel bundle peaking or radial distribution is reduced in a BWR core because of greafer sfeam voids in the center bundles of the care. A control rod operating procedure is also used to maintain approximately the same radial power shape throughout an operating cycle. 

The power profile along core radius was shaped to flatten power distribution in all considered variants. The radial non-uniformity of power distribution is reduced by changing the content of fissile material in the fuel, which increases from the core centre to the periphery. The maximal radial power peaking factor Kr"" was less than or equal to 1.25 in all calculations described below. 

Thus in principle there are two pieces of information relating to each pair of atoms that can be determined from the electron diffraction data (provided we ignore more complicated matters such as anharmonicity). Refinement of stmctures involves constructing an appropriate mathematical model of the molecule, such as an initial set of Cartesian coordinates. While this is a straightforward choice, it actually requires the refinement of more variables than is strictly necessary, as there are only 3A 6 degrees of freedom for an A-atom molecule (Section 8.2.1), and this number can be further reduced if symmetry is taken into account. This point is extremely important we have already seen in the examples of P3AS and PBrF2S that different atom-pair distances can fall under the same peak in the radial distribution curve, with the result that we could have more variables to define than we have data. 

For 1 = 0 the monopole structure can be determined completely if Boo(h) is known. In fact, the phase problem of reduces to the determination of the sign of F(,(,. This is usually not too difficult a task for Bqo as plausible arguments can be made concerning the corresponding radial mass distribution v fr) of the resonant label atoms. Once the signs of the sinusoidal function BQQ(h) are known for each peak, the phases of Ao(,(h) can be determined directly by using the cross term. 

The effect of metal loading on the reducibility was examined with PdNaY (71). For samples calcined at 500°C, the TPR peak maximum shifts from 190 to 150°C the Pd loading increases from 2.0 to 6.7 wt%. This has been attributed to the formation of ion pairs in sodalite cages. The reduction conditions are important for the resultant metal dispersion. TEM and radial electron distribution (RED) evidence shows that reduction of Ir ions in an H2 flow results in much smaller Ir aggregates than reduction under static H2 (173). 

Temperature influences both molecular diffusion and viscosity, and hence the distribution of velocities of the different fluid lines (see also Fig. 3.1). Consequently, both convective and diffusive mass transport are, in principle, affected. An increase in temperature (and the concomitant decrease in viscosity) promotes radial mixing, thus reducing sample broadening and increasing the recorded peak height. 

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