Graphite-fabric technique

Alternative materials for bipolar plates include graphite, stainless steels, titanium and aluminium, all with a developed fabrication technique, and coating technique if needed. Major competitors UTC Fuel Cells has an active fuel cell bus programme, but give sparse details of its flow plate and other technology. (See UTC web site.)... 

The selection of materials and fabrication techniques is crucial for an adequate sensor function and the performance of a sensor often ultimately depends upon these factors. Consequently, future developments in sensor design will inevitably focus upon the technology of new materials. Materials used in electrochemical sensors are classified as (1) materials for the electrode and supporting substrate (metals platinum, gold, silver, and stainless steel carbon-based materials graphite, carbon black, and carbon fibre new mixed materials or organic electroconductive... 

In 1975, the fabrication of a chiral electrode by permanent attachment of amino acid residues to pendant groups on a graphite surface was reported At the same time, stimulated by the development of bonded phases on silica and aluminia surfaces the first example of derivatized metal surfaces for use as chemically modified electrodes was presented. A silanization technique was used for covalently binding redox species to hydroxy groups of SnOj or Pt surfaces. Before that time, some successful attemps to create electrode surfaces with deliberate chemical properties made use of specific adsorption techniques... 

Wurtzite-type BN (wBN or yBN) is close to cubic BN in density and will transform to cubic BN above 55 GN/m and 1450°C. It will also convert to hexagonal BN below about 60GN/m and above 1000°C. wBN is a metastable form at pressures and temperatures where cBN is fabricated. The powder can be synthesized from graphitic or hexagonal BN by shock compression and an alkaline fusion technique. The effect of TiBa and boron additives on the transformation of wBN to cBN has been studied. TiBa shifts the formation region of cBN to higher temperatures while B shifts it to lower temperatures. wBN can be synthesized by static compression at pressures exceeding 5.5 GN/m and low temperatures or by shock compression . ... 

Due to high biocompability and large surface are of cobalt oxide nanoparticles it can be used for immobilization of other biomolecules. Flavin adenine FAD is a flavoprotein coenzyme that plays an important biological role in many oxidoreductase processes and biochemical reactions. The immobilized FAD onto different electrode surfaces provides a basis for fabrication of sensors, biosensors, enzymatic reactors and biomedical devices. The electrocatalytic oxidation of NADH on the surface of graphite electrode modified with immobilization of FAD was investigated [276], Recently we used cyclic voltammetry as simple technique for cobalt-oxide nanoparticles formation and immobilization flavin adenine dinucleotide (FAD) [277], Repeated cyclic voltammograms of GC/ CoOx nanoparticles modified electrode in buffer solution containing FAD is shown in Fig.37A. 

Carbons can be made in many aUotropic forms crystalline diamond, graphite, noncrystalhne glassy carbon, and quasicrystaUine pyroHtic carbon. Among these, only pyrolitic carbon is widely utilized for implant fabrication it is normally used as a surface coating. It is also possible to coat surfaces with diamond. Although the techniques of coating with diamond have the potential to revolutionize medical device manufacturing, it is not yet commercially available [Park and Lakes, 1992]. 

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