Solid interfaces, plasma

Franco T, HoshiarDin Z, Szabo P, Lang M, and Schiller G. Plasma sprayed diffusion barrier layers based on doped perovskite-type LaCr03 at substrate-anode interface in solid oxide fuel cells. J. Fuel Cell Sci. Technol. 2007 4 406-412. 

Charge transfer and adsorption phenomena at electrified interfaces, including plasma-solid systems... 

Cenacchi, V. Baratte, S. Gicioni, P. Frigerio, E. Long, J. James, C. LC-MS-MS determination of exemestane in human plasma with heated nebulizer interface following solid-phase extraction in the 96 well plate format, J.Pharm.BiomedAnal., 2000, 22, 451-460. 

McLoughlin, D.A., Olah, T.V., and Gilbert, J.D. 1997. A direct technique for the simultaneous determination of 10 drug candidates in plasma by liquid chromatography/atmospheric pressure chemical ionization mass spectrometry interfaced to a Prospekt solid-phase extraction system. J. Pharm. Biomed. Anal. 15 1893. 

The MC-ICP-MS consists of four main parts 1) a sample introduction system that inlets the sample into the instrument as either a liquid (most common), gas, or solid (e.g., laser ablation), 2) an inductively coupled Ar plasma in which the sample is evaporated, vaporized, atomized, and ionized, 3) an ion transfer mechanism (the mass spectrometer interface) that separates the atmospheric pressure of the plasma from the vacuum of the analyzer, and 4) a mass analyzer that deals with the ion kinetic energy spread and produces a mass spectrum with flat topped peaks suitable for isotope ratio measurements. 

The applicability of the APCI interface is restricted to the analysis of compounds with lower polarity and lower molecular mass compared with ESP and ISP. An early demonstration of the potential of the APCI interface is the LC-APCI-MS-MS analysis of phenylbutazone and two of its metabolites in plasma and urine (128). Other applications include the LC-APCI-MS analysis of steroids in equine and human urine and plasma (129-131), the determination of six sulfonamides in milk samples after a simple solid-phase extraction and LC separation (132), of tetracyclines in muscle at the 100 ppb level (133), of fenbendazole, oxfendazole, and the sulfone metabolite in muscle at the 10 ppb level, and of five thyreostats in thyroid tissue at the 1 ppm level (134). 

High power pulsed lasers are used to produce plasmas and thus to sample and excite the surfaces of solids. Improvements in minimum detectable limits and decreases in background radiation and in interelement interference effects result from the use of two lasers (99) (see Surface and interface analysis). 

Studies of the role of protein-surface interactions in blood coagulation were done by Vroman 56). The plasma proteins were adsorbed onto various hydrophilic or hydrophobic surfaces. Vroman showed that fibrinogen was an important component of the plasma protein layer adsorbed to the solid/liquid interface. 

Electrochemical reactions occur at the interface between two phases with sufficiently different conduction behavior, i.e. a predominantly ion-conducting electrolyte phase and an electrode phase with predominantly electronic conduction. Among all possible types of interfaces the most intensively applied are solid metal liquid electrolyte and solid metal solid electrolyte. Electrode systems which have been much less studied are those formed by combining either a solid or liquid conducting phase with a low-temperature gas discharge (plasma). 

This chapter aims to discuss and summarize theoretical and practical aspects of such plasma interfaces, presenting the existing examples from our own recent work on plasma electrochemical reactions between typical ionic liquids and plasmas. First, we address the plasma state and essential properties with respect to its application in electrochemistry. Today, low temperature plasmas - mostly in the form of radiofrequency or microwave plasmas - play an important role in the treatment or modification of solid surfaces. However, as plasma chemistry is usually not an element of chemistry curricula, we include a very brief introduction but refer the reader to the literature for more detailed information. 

Plasma electrochemistry — Gas plasmas possess mixed electronic and ionic conductivities. This allows their use as ion conductors in electrochemical cells, i.e., interfaced with electronic conductors [i, ii], and, when they are in intimate contact with solid or liquid electrolytes, they can be also used as the electronically conducting... 

Most of these studies have been performed on relatively uncharacterized LTI carbon surfaces. Since we assume that a large part of blood compatibility depends on the nature of the solid-plasma interface, particularly with respect to protein adsorption, we have elected to characterize some of the surface properties of LTI carbon in hopes of further understanding the solid-blood interaction mechanisms. 

Plasma No specific functional group is needed No initiator Gas phase (gas-solid interface)... 

Timely and up-to-date, this book provides broad coverage of the complex relationships involved in the interface between gas/solid, liquid/solid, and solid/solid...addresses the importance of the fundamental steps in the creation of electrical glow discharge... describes principles in the creation of chemically reactive species and their growth in the luminous gas phase... considers the nature of the surface-state of the solid and the formation of the imperturbable surface-state by the contacting phase or environment... offers examples of the utilization of LCVD in interface engineering processes...presents a new perspective on low-pres.sure plasma and emphasizes the importance of the chemical reaction that occur in the luminous gas phase...and considers the use of LCVD in the design of biomaterials. 

In chemical vapor deposition (CVD) reactive vapor precursors react to produce solid materials in the gas phase or at the solid-gas interface on the substrate surface at appropriate temperatures. Typical precursors used in the CVD process are metal hydrides, metal chlorides, and metal organic compounds. In the case that the precursor species are metal organic compounds, the process is called metal-organic chemical vapor deposition (MOCVD). The precursor molecules are introduced into a reactor sometimes with a carrier gas and decompose by means of heat, irradiation of UV light, or electrical plasma formed in the gas. Thermal CVD is the most commonly used method. This technique has an advantage that refractory materials can be vapour-deposited at relatively low temperatures,... 

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