Expanded electron transport

Biologically, iron plays crucial roles in the transport and storage of oxygen and also in electron transport, and it is safe to say that, with only a few possible exceptions in the bacterial world, there would be no life without iron. Again, within the last forty years or so, the already rich organometallic chemistry of iron has been enormously expanded, and work in the whole field given an added impetus by the discovery and characterization of ferrocene. 

Fe-4S] clusters, all with cysteinyl-S completing tetrahedral Fe coordination (Figure 1) and the function was exclusively electron transport. New types of electron transfer Fe-S clusters involving cubane-type [3Fe S] clusters and double-cubane-type [8Fe-7S] clusters have subsequently been characterized (Figure 1). Moreover, the known functions of Fe-S centers have now expanded to include coupling... 

Based on the Tang s excellent work, the authors examined various combinations of organic molecules and proposed new OLED device structures.32-36 In particular, the discovery of unipolar electron-transport materials, 2-(4 -biphenyl)-5-(4"ferf-butylphenyl)-l,3,4-oxadiazole (PBD), greatly expanded the possibilities of OLED materials and cell structures. Thus, we could classify OLED cell structures into three categories.37 A detailed classification of cell structures is described in Sections 3 and 4. 

Fig. 15. The Z-scheme for two photosystems (A) The original Z-scheme of Hill and Bendall (1960) (B) an expanded Z-scheme of Hill (1965) (C) a contemporary Z-scheme. (A) modified from Hill and Bendall (1960) Function of two cytochrome components in chloroplasts A working hypothesis. Nature 186 137 (B) from Hill (1965) The biochemist s green mansions the photosynthetic electron-transport chain in plants. In PN Campbell and GD Greville (eds) Essays in Biochemistry, 1 143. Acad Press.

The concept of two distinct but interlinked mechanical processes, expanded here as the coupling of hydrophobic and elastic consilient mechanisms, entered the public domain in the publication of Urry and Parker. Experimental results on elastic-contractile model proteins forged the concept, and the work of Urry and Parker extended the concept to contraction in biology. Unexpected in our examination of the relevance of this perspective to biology was to find the first clear demonstration of the concept in biology in a protein-based machine of the electron transport chain as a transmembrane protein of the inner mitochondrial membrane. Unimaginable was the occurrence of the coupled forces precisely at the nexus at which electron transfer couples to proton pumping. 

Polyaniline is the conducting polymer most commonly used as an electrocatalyst and immobilizer for biomolecules [258-260]. However, for biosensor applications, a nearly neutral pH environment is required, since most biocatalysts (enzymes) operate only in neutral or slightly acidic or alkaline solutions. Therefore, it has been difficult or impossible to couple enzyme catalyzed electron transfer processes involving solution species with electron transport or electrochemical redox reactions of mostly polyaniline and its derivatives. Polyaniline is conducting and electroactive only in its protonated (proton doped) form i.e., at low pH valnes. At pH values above 3 or 4, polyaniline is insulating and electrochemically inactive. Self-doped polyaniline exhibits redox activity and electronic conductivity over an extended pH range, which greatly expands its applicability toward biosensors [209, 210, 261]. Therefore, the use of self-doped polyaniline and its derivatives could, in principle. 

Electronic vacancies pertaining to the host are produced right below Fp, generating a gap between the conduction band and the valence band of a metal. The electron transportation can also expand the original bandgap of a semiconductor from Eqo to Fqi. 

It is obvious that the photoanode materials with a high specific surface area and porosity can help to expand the contact area between the dye-adsorbed surface and solar radiation [46-49]. Therefore, in order to further increase the efficiency of the solar cell, it seems to be necessary to develop T1O2 structure that possesses favorable characteristics such as faster electron transport rate, high porosity, and larger surface area compared to nanoparticles [50-52]. Hwang et al. used a... 

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