Membranes solid

Royce W. Murray is Kenan Professor of Chemistry at the University of North Carolina at Chapel Hill. He received his B.S. from Birmingham Southern College in 1957 and his Ph.D. from Northwestern University in 1960. His research areas are analytical chemistry and materials science with specialized interests in electrochemical techniques and reactions, chemically derivatized surfaces in electrochemistry and analytical chemistry, electrocatalysis, polymer films and membranes, solid state electrochemistry and transport phenomena, and molecular electronics. He is a member of the National Academy of Sciences. 

Fluorinated polymers, especially polytetrafluoroethylene (PTFE) and copolymers of tetrafluoroethylene (TFE) with hexafluoropropylene (HFP) and perfluorinated alkyl vinyl ethers (PFAVE) as well as other fluorine-containing polymers are well known as materials with unique inertness. However, fluorinated polymers with functional groups are of much more interest because they combine the merits of pefluorinated materials and functional polymers (the terms functional monomer/ polymer will be used in this chapter to mean monomer/polymer containing functional groups, respectively). Such materials can be used, e.g., as ion exchange membranes for chlorine-alkali and fuel cells, gas separation membranes, solid polymeric superacid catalysts and polymeric reagents for various organic reactions, and chemical sensors. Of course, fully fluorinated materials are exceptionally inert, but at the same time are the most complicated to produce. 

Rule G, Henion J. 1999. High-throughput sample preparation and analysis using 96-weU membrane solid-phase extraction and liquid chromatography—tandem mass spectrometry for the determination of steroids in human urine. J Am... 

Code, P, Hult, A., Jannasch, P, Johansson, M., Karlsson, L. E., Lindbergh, G., Malmstrom, E. and Sandquist, D. 2006. A novel sulfonated dendritic polymer as the acidic component in proton conducting membranes. Solid State Ionics 177 787-794. 

For the sake of discussion, we have divided the separators into six types—microporous films, non-wovens, ion exchange membranes, supported liquid membranes, solid polymer electrolytes, and solid ion conductors. A brief description of each type of separator and their application in batteries are discussed below. 

Solid-phase extraction membrane. Solid-phase extraction cartridge. [Courtesy Alhech Associates,... 

N. A. Chaniotakis, Thick Membrane, Solid Contact Ion Selective Electrode for the Detection of Lead at Picomolar Levels, Anal. Chem. 2005, 77, 1780. 

METAL SOLUTION U SAMPLE MEMBRANE SOLID (METAL) METAL... 

In summary, it is perfectly legitimate to design CWEs with solid-state internal contact and to expect electrochemical performance comparable to the conventional ISE. However, the design of the membrane/solid interface has to be done with the understanding of the electrochemical processes at such an interface. The problems include the drift scale with the surface area and the length of the internal contact, specifically with its parasitic capacitance and resistance. From this consideration alone, it can be concluded that such problems can be minimized by decreasing the... 

Interactions with Membrane Components. In aqueous systems milk fat globule membrane lipids and the non-lipid membrane solids were found to accelerate the oxidation of milk fat at 50°C, but exhibited antioxidant effects at 95°C (Chen, Z. Y. Nawar, W. W., University of Massachusetts at Amherst, unpublished data). 

Fig. 6.13 Distribution of the angle between P-N vector and bilayer normal in pure DPPC membrane (solid line) and in membranes containing cholesterol 11 mol% (dotted line), 50 mol% structure A (dash dot line), and structure B (dashed line). When cosine is positive, the P—N vector points into the water layer.

Nomura, K., Inaba, T., Morigaki, K., Brandenburg, K., Seydel, U., Kusumoto, S. Interaction of lipopolysaccharide and phosphohpid in mixed membranes solid-state 31P-NMR spectroscopic and microscopic investigations. Biophys J 95 (2008) 1226-1238. 

The functioning of an ion-selective electrode (ISE)4 6 is based on the selectivity of passage of charged species from one phase to another leading to the creation of a potential difference. The fundamental theoretical formulation is the same as that developed for liquid junction potentials (Section 2.11). In the case of ISEs one phase is the solution and the other a membrane (solid or liquid in a support matrix). The membrane potential, Em, for an ion, i, of charge zf is... 

In these sensors the technology developed for ISFET construction is used in conventional electrodes. Links between the membrane and internal reference are metallic (ohmic contact), by deposition of the metal on the membrane (solid state membranes), or by deposition of an ion-selective membrane on a metal. This latter is an integrated sensor. 

There are also techniques involving the use of nonporous, solid or liquid membranes that separate the donor phase from the receiving phase by an evident phase boundary. Most often used are three-phase systems (donor phase, membrane, and acceptor phase) or two-phase systems, in which one of the surrounding phases is the same as the membrane. Solid membranes are made of chemically resistant, hydrophobic polymers (PTFE, PVDF, PS, PP, silicates), metals (Pd alloys), or ceramic materials. Channels of membrane modules have a volume ranging from 10 to 1000 pL and, according to their geometry, can be classified as planar or fibrous. For setting up a membrane system, two modes can be used the membrane can be immersed in a sample (membrane in sample, MIS) or the sample can be introduced into a membrane (sample in membrane, SIM). In both systems, only a small amount of sample is in direct contact with membrane, because ratio of the membrane surface area to the sample volume is small. 

I. Honma, H. Nakajima, and S. Nomura. High temperature proton conducting hybrid polymer electrol3de membranes. Solid State Ionics 154, 707-712 2002. 

Other types of electrodes are listed in Table 8.9. The glass membrane is replaced by a synthetic single-crystal membrane (solid-state electrodes), by a matrix (e.g., inert silicone rubber) in which precipitated particles are imbedded (precipitate electrodes), or by a liquid ion-exchange layer (liquid-liquid membrane electrodes). The selectivity of these electrodes is determined by the composition of the membrane. All these electrodes show a response in their electrode potentials according to the Nemst equation. 

Ieronimo, M. (2008) Towards the activity of the antimicrobial peptide PGLa in cell membranes. Solid-state NMR studies of PGIm and magainin2, Ph.D. thesis, University of Karlsruhe. 

H. Deng, M. Zhou and B. Abeles, Diffusion-reaction in porous mixed ionic-electronic solid oxide membranes. Solid State Ionics, 74 (1994) 75-84. 

B.C.H. Steele, Interfacial reactions associated with ceramic ion transport membranes. Solid State ionics, 75 (1995) 157-165. 

RS Plumb, RD Gray, AJ Harker, SJ Taylor. Use of reduced sorbent bed and disk membrane solid-phase extraction for the analysis of pharmaceutical compounds in biological fluids, with applications in the 96-well format. J Chromatogr B 687 457 161, 1996. 

Plumb, R.S. Gray, R.D.M. Jones. C.M. "Use of Reduced Sorbent Bed and Disk Membrane Solid-Phase Extraction for the Analysis of Pharmaceutical Compounds in Biological Fluids, with Application in the 96-Well Format, J. Chromatogr. B 694, 123-133 (1997). 

Rule, G. Henion, J. High-Throughput Sample Preparation and Analysis Using 96-Well Membrane Solid-Phase Extraction and Liquid Chromatography-Tandem Mass Spectrometry for the Determination of Steroids in Human Urine, J. Am. Soc. Mass Spectrom. 10, 1322-1327 (1999). 

Senseman, S. A., Lavy, T. L., Mattice, J. D., Myers, B. M. and Skulman, B. W. 1993. Stability of various pesticides on membranous solid-phase extraction media. Environ. Sci. Tech., 27 516-519. 

Ceramic Membranes/Solid Oxide Fuel Cells Photovoltaics... 

These electrodes have the silver ion as the mobile ion. Immersion in a solution of the selective ion results in a change in the silver ion activity, resulting in the development of a potential over the interfaces of the membrane. The theory will be discussed in detail for the crystal membrane solid-state electrode section to follow. 

In foe latter case, the two phases are separated by a hydt ophohk ot liydtophilic membrane (solid supported interface). The engynie is soluble in the-aqueous phase and substrate is added up to its maximum solubility in foe aqueous phase. Substrates and. products are distributed according to their hydrophilic or hydro-phobic properties. Use membrane axes has to be large enough to avoid mass transfer limitations. High membrane areas may he achieved fey Hat membrane stacks or fey hollow fiber modules. 

The control coefficients were calculated for various levels of stimulation. Because these levels correspond to different oscillation periods, we can plot the Ci against the period (Fig. 4.3B). There are several notable features. The control is distributed mainly between the IP3 dynamics (dash-dotted line), IP3R dynamics (dotted line), and the fluxes through the ER membrane (solid line). The fast oscillations are dominated by the exchange fluxes through the ER membrane and the IP3R dynamics. Interestingly,... 

Solid-infusion processes Emulsion liquid membranes Solid-supported liquid membranes Fnam fractionation Bubble fractionation... 

EINECS 231-672-5 HSDB 749 Iodic acid, sodium salt lodio acid (HI03), sodium salt Natriumjodat NSC 77387 Sodium iodate. Antiseptic, disinfectant, feed additive reagent. Used medicinally as an antiseptic, particularly in mucous membranes. Solid d = 4.28 soluble in HzO (9 g/100 ml), insoluble in organic solvents LD (dog iv) = 200 mg/kg. Atomergic Chemetals Mallinckrodt Inc. 

Ill. Sojo, L. E. and Djauhari, J., Determination of chlorophenolics in waters by membrane solid-phase extraction comparison between Cig and activated carbon membranes and between modes of extraction and elution, J. Chromatogr. A, 840, 21-30, 1999. 

Chee, K. K., Wong, M. K., and Lee, H. K., Determination of organochlorine pesticides in water by membranous solid-phase extraction, and in sediment by microwave-assisted solvent extraction with gas chromatography and electron capture detector and mass spectrometric detection, J. Chromatogr. A, 736, 211-218, 1996. 

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