Active site electrical conductivity

The above mechanistic aspect of electron transport in electroactive polymer films has been an active and chemically rich research topic (13-18) in polymer coated electrodes. We have called (19) the process "redox conduction", since it is a non-ohmic form of electrical conductivity that is intrinsically different from that in metals or semiconductors. Some of the special characteristics of redox conductivity are non-linear current-voltage relations and a narrow band of conductivity centered around electrode potentials that yield the necessary mixture of oxidized and reduced states of the redox sites in the polymer (mixed valent form). Electron hopping in redox conductivity is obviously also peculiar to polymers whose sites comprise spatially localized electronic states. 

Different results were reported by Sasaki et al. [67], They studied the electrical conductivity and polarization performance of Ln, xSrxMn03 (Ln = Pr, Nd, Sm, and Gd) and found that the influence of the lanthanide ions at the A-site on the electrical conductivity and electrocatalytic activity is not significant. For example, the electrical conductivity was -200 Scm-1 at 1000°C for all Ln07Sr03MnO3 and the polarization performance showed no significant dependence on the kind of lanthanide elements. 

A clue as to why the cationic N-terminal region and the hydrophobic C-terminal portion of SP are required for full histamine-releasing activity comes from studies of the electrical conductivity of black lipid membranes in the presence of peptides. Using SP, these authors [176] concluded that SP probably binds by its N-terminal region to negatively charged sites on membrane lipids, while the C-terminal portion of the molecule penetrates the hydrophobic core of the lipid bilayer, which could induce an increase in membrane permeability or a slight alteration in membrane conformation. 

Active centers, nature of, 10 96 Active site, 27 210-221 in catalysts, 17 103-104, 34 1 for olefin chemisorption, 17 108-113 dual-site concept, 27 210 electrical conductivity, 27 216, 217 ESCA, 27 218, 219 ESR, 27 214-216 infrared spectroscopy, 27 213, 214 model, 27 219-221 molybdena catalyst, 27 304-306 Mdssbauer spectroscopy, 27 217, 218 nonuniform distribution, transport-limited pellets, 39 288-291... 

Conductivity electrical, 27 20, 21 active site, 27 216, 217 temperature dependence, 27 20, 21 tin-antimony oxide, 30 100, 109 tin(IV) oxide, 30 108-109 Configurational-bias Monte Carlo method (CB-MC)... 

The supramolecular bis-aniline cross-linked metallic NPs/enzyme composite does not only act as a conducting matrix that electrically contacts the redox center with the electrode, but the NPs may also provide catalytic sites that enhance the biocatalytic transformations at the enzyme active site. This has been demonstrated by the effective... 

As can be seen from Fig. 12, the experiment is very well described by Eq. (35). Finally, measurements of the electric conductivity of the binary mixtures of the initial reagents have played an important role in substantiating Scheme (35) 149-152>. The electric conductivity of any binary mixture of the initial reagents (epoxy compounds, TA and alcohol) turned out to be over two orders of magnitude lower than that of the triple system. These experiments show that the interaction of all three reagents is essential for generation of the ionic particles. They have also completely rejected the possibility of formation of active sites directly via interaction of TA with alcohol139,... 

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