Switching protonic conductivity

Figure 29 Schematics for the switching protonic conductivity based on phase transitions within the hierarchically self-assembled polymer complexes based on PS-fc-P4VP and PDP-I-MSA. SAXS-pattems and DC-conductivity as a function of temperature are shown. The geometry of the conducting self-assembled domains is illustrated. (Reproduced with permission from Ref. 82. American Association for the Advancement of Science, 1998. 82. J. Ruokolainen, R. Makinen, M. Torkkeli, T. Makela, R. Serimaa, G. ten Brinke,...

Thermally or photochemically induced proton transfers represent bistable switching processes and are of interest for information storage. A lateral transfer of information on the surface of biological membranes is thought to occur by fast proton conduction through protonic networks [8.234]. 

Activation of the contractile machinary by means of the interaction of Ca " with Troponins (TN) is amenable to a new interpretation in the framework of the proto-osmotic approach. It is suggested that the above interaction serves to establish the hydrogen-bonded systems of F-actin. Each TN overlaps two G-actins and is thus in a position to interfere with their mutual linkages and break the protic circuit of F-actin in the absence of Ca ". The interaction of Ca " " with TN-C and of the latter with TN-I and TN-T may restore the normal linkages between the affected G-actins and switch on the circuit of H along the F-actin. All other modes of activation are also suggested to be by means of the establishment of proton conduction paths in the myofilaments, from SI to the Mline and the Z disc. 

Most organizations and companies stopped work in this area between 1990 and 1995, and some of them switched to other systems when work on fuel cells with acidic, proton-conducting membranes began to take off in the mid-1990s. 

Electrical properties of liquids and solids are sometimes crucially influenced by H bonding. The ionic mobility and conductance of H30 and OH in aqueous solutions are substantially greater than those of other univalent ions due to a proton-switch mechanism in the H-bonded associated solvent, water. For example, at 25°C the conductance of H3O+ and OH are 350 and 192ohm cm mol , whereas for other (viscosity-controlled) ions the values fall... 

Despite this enormous viscosity, fused H3PO4 (and D3PO4) conduct electricity extremely well and this has been shown to arise from extensive self-ionization (autoprotolysis) coupled with a proton-switch conduction mechanism for the... 

Figure 12.17 Schematic representation of proton-switch conduction mechanism involving [U2PO4I phosphoric acid.

H2SO4.Z2H2O, are known with = 1, 2, 3, 4 (mps 8.5", -39.5". -36.4" and -28.3% respectively). Other compounds in the H2O/SO3 system are H2S2O7 (mp 36") and H2S4O13 (mp 4"). Anhydrous H2SO4 is a remarkable compound with an unusually high dielectric constant, and a very high electrical conductivity which results from the ionic self-dissociation (autoprotolysis) of the compound coupled with a proton-switch mechanism for the rapid... 

During the course of the work, we also conducted further studies of the reactions of proton hydrates with CH3COCH3 and CH3COOCH3. The reaction mechanisms were found to change from proton transfer to ligand switching and ultimately to an association process, which would be equivalent to adsorption in the case of bulk systems. 

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