Potential dependent attenuated total

PDATRFTIRS Potential dependent attenuated total reflectance Fourier transform infrared spectroscopy... 

Adsorption of CN on a silver metal film was reported by Hatta et al. [112], using multiple internal reflection in an ATR (attenuated total reflection) prism configuration. Basically the same features were observed by Hatta et al. as in the external reflection approach, namely a potential-dependent band located between 2100 and 2118 cm assigned to the adsorbed CN ion and another band located at 2143 cm , assigned to the Ag(CN)2 complex. The feature at 2167 cm was not observed, because of the limited potential range used in this experiment to avoid the dissolution of the silver film [112]. 

When only taking into account the concentration polarization in the pores (disregarding ohmic potential gradients), we must use an equation of the type (18.15). Solving this equation for a first-order reaction = nFhjtj leads to equations exactly like (18.18) for the distribution of the process inside the electrode, and like (18.20) for the total current. The rate of attenuation depends on the characteristic length of the diffusion process ... 

Besides measurements, there are potential benefits in the observation of other nuclides for diffusion measurements. There may be fewer problems with resonance overlap of different species or less interference from solvent or impurity resonances, for example, or the compound of interest may simply lack hydrogen as is often the case with counter-ions. In this case, one should be aware that optimum parameters for measurement may not be suitable for nuclides of lower magnetogyric ratio, 7. This is because the total effective gradient strengths employed also depend on this parameter and, as can be seen from the Stejskel-Tanner equation (Eq. (9.6)), the degree of attenuation of resonance intensity will be reduced as 7 becomes smaller. This is illustrated in Fig. 9.23 where the decay profiles for four different nuclides are shown, having been calculated with identical diffusion parameters but with the appropriate 7... 

The scattering length R may also be determined from direct measurements of the total cross section in thick material. In this case, the neutrons with energies corresponding to the resonance energies are removed by absorption and the measured transmission depends mainly on those neutrons whose energies lies between resonances. These neutrons are attenuated effectively only by potential scattering. 

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