Electronic conductivity modification

Rotations around torsional barriers induce changes in chain conformation. For conjugated systems like polydiacetylenes, flow-induced changes in chain conformation can have a profound influence on the photon absorption and electronic conductivity properties of the material [73]. Flow-induced changes in molecular conformation form the basis for several technically important processes, the best known examples are the production of oriented fibers by gel spinning [74], the compatibility enhancement [75] and the shear-induced modification of polymer morphology [76]. 

Physical properties, such as magnetism and electronic conduction, are largely unexplored for Prl2. This is not because pure Prl2 caimot be made (see 4.2). Rather, that it is extremely difficult, if not impossible, to produce single-phase, i.e., one-modification samples on a scale sufficiently large for these measure-... 

To reduce the formation of carbon deposited on the anode side [2], MgO and Ce02 were selected as a modification agent of Ni-YSZ anodic catalyst for the co-generation of syngas and electricity in the SOFC system. It was considered that Ni provides the catalytic activity for the catalytic reforming and electronic conductivity for electrode, and YSZ provides ionic conductivity and a thermal expansion matched with the YSZ electrolyte. 

Carbon. The electronically conductive carbons are derived from the hexagonal crystalline modification—graphite. 

Modification and functionalisation of natural polyenes, the carotenoids, is an efficient way for the molecular engineering of polyenic chains. Terminal bis-pyridinium carotenoids, termed caroviologens, represent an approach to electron conducting molecular wires (5). Fitting polyconjugated chains with an electron donor group on one end and an electron acceptor on the other end yields push-pull systems of type 1 that may be considered as polarized, unidirectional (oriented) molecular wires and also possess marked NLO properties. 

Electrochemical Behavior of PPy-GOD Film Electrode with Pharmaceutical Drugs. Although the chemically modified electrode has been developed for more than a decade, and many kinds of materials have been used for the modification of the electrode surface, the enzyme modified electrode has rarely been used for the study of electroactive species. This is probably due to the fact that the enzyme is not electronically conductive and also it is difficult to immobilize an enzyme on the electrode surface. So far, biological lipids have been used to modify the electrode, and the modified electrode shows a selectivity for hydrophobic molecules because the lipid molecule is hydrophobic (37-39). 

NEMCA effect — The term NEMCA is the acronym of Non-faradaic Electrochemical Modification of Catalytic Activity. The NEMCA effect is also known as electrochemical promotion (EP) or electropromotion. It is the effect observed on the rates and selectivities of catalytic reactions taking place on electronically conductive catalysts deposited on ionic (or mixed ionic-electronic) supports upon application of electric current or potential (typically 2 V) between the catalyst and a second (counter or auxiliary) electrode also deposited on the same support. The catalytic reactants are usually in the gas phase. 

The aforementioned requirements on surface stability are typical for all exposed areas of the metallic interconnect, as well as other metallic components in a SOFC stack (e.g., some designs use metallic frames to support the ceramic cell). In addition, the protection layer for the interconnect, or in particular the active areas that interface with electrodes and are in the path of electric current, must be electrically conductive. This conductivity requirement differentiates the interconnect protection layer from many traditional surface modifications as well as nonactive areas of interconnects and other components in SOFC stacks, where only surface stability is emphasized. While the electrical conductivity is usually dominated by their electronic conductivity, conductive oxides for protection layer applications often demonstrate a nonnegligible oxygen ion conductivity as well, which leads to scale growth beneath the protection layer. With this in mind, a high electrical conductivity is always desirable for the protection layers, along with low chromium cation and oxygen anion diffusivity. 

The silicon surface can be stabilized using surface modification techniques which are divided into three categories (1) attachment of redox mediator which consumes the holes on the surface (2) attachment of electronically conducting polymer and (3) coating with thin metal or semiconducting films to create a buried semiconductor interface. Combinations of these approaches can also be used to stabilize the sihcon surface. ... 

In the 1970s, interest arose in the modification of electrode surfaces by covalent attachment of monolayers of different species to electrode surfaces. Electrodes modified with thicker polymeric films and inorganic layers were introduced later. Paralleling this work was activity in the field of electronically conductive polymers and organic metals, many of which can be produced electrochemically. More complex structures (bilayers, arrays, biconductive films) have also been prepared. 

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