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Membrane reduction surface

As mentioned in Section V.H.2, highly important room temperature polymeric systems are based on polyacrylonitrile (PAN) plasticized with PC and EC. These systems are obviously highly reactive with lithium. It is clear that Li, in contact with these membranes, develops surface chemistry which is dominated by the reduction of EC and PC to R0C02Li (Table 3 and Schemes 1 and 3, Section V.C, and related discussion). [Pg.383]

Interest in protein and peptide interactions with phospholipid membranes and surfaces originates from its importance for both key biophysical processes (eg, atherosclerosis, Alzheimer s, and other plaque-related diseases) and a wide range of biomedical applications. For example, control of protein/peptide adsorption allows reduction of inflammation and other unwanted biopharmaceutical effects in phospholipid-based biomaterials and dmg delivery but also improved signal-to-noise in biosensors and... [Pg.61]

Fig. 18 Membrane catalytic systems (a) TEM images of pores of an alumina membrane modified with a PAA/PAH/(platinum NP) film. Modification of membrane pore surfaces using (b) the LbL deposition of PAA/PAH/(platinum NP) films, or (c) the LbL deposition of PAA/PEI-Pt films followed by a reduction. Reprinted from [125] Copyright 2009 with permission fi om Elsevier... Fig. 18 Membrane catalytic systems (a) TEM images of pores of an alumina membrane modified with a PAA/PAH/(platinum NP) film. Modification of membrane pore surfaces using (b) the LbL deposition of PAA/PAH/(platinum NP) films, or (c) the LbL deposition of PAA/PEI-Pt films followed by a reduction. Reprinted from [125] Copyright 2009 with permission fi om Elsevier...
T. Ishigami, K. Amano, A. Fujii, Y. Ohmukai, E. Kamio, T. Maruyama, H. Matsuyama, Fouling reduction of reverse osmosis membrane by surface modification via layer-by-layer assembly, Sep PurifTechnol, 99 (2012) 1-7. [Pg.652]

Mlcrofiltra.tlon, Various membrane filters have been used to remove viral agents from fluids. In some cases, membranes which have pores larger than the viral particle can be used if the filtration is conducted under conditions which allow for the adsorption of the viral particle to the membrane matrix. These are typically single-pass systems having pore sizes of 0.10—0.22 lm. Under situations which allow optimum adsorption, between 10—10 particles of poHovims (28—30 nm) were removed (34—36). The formation of a cake layer enhanced removal (35). The titer reduction when using 0.10—0.22 p.m membrane filters declined under conditions which minimized adsorption. By removal standards, these filters remove vimses at a rate on the low end of the desired titer reduction and the removal efficiency varies with differences in fluid chemistry and surface chemistry of viral agents (26). [Pg.144]

The voltage used for electro dialysis is about 1 V per membrane pair, and the current flux is of the order of 100 A/m of membrane surface. The total power requirement increases with the feedwater salt concentration, amounting to about 10 MW per m product water per 1000 ppm reduction in salinity. About half this power is required for separation and half for pumping. Many plant flow arrangements exist, and their description can be found, along with other details about the process, in References 68 and 69. Many ED plants, as large as 15,000 vsf jd, are in operation, reducing brackish water concentration typically by a factor of 3—4. [Pg.253]

The principal cathodic reaction on the upper surface of the membrane is the reduction of Cu " that is formed by the reaction of Cu with dissolved oxygen in the water these Cu ions are provided partly from the diffusion through the pores in the oxide membrane from within the pit and partly from those produced by cathodic reduction (equation 1.154). Lucey s theory thus rejects the conventional large cathode small anode relationship that is invoked to explain localised attack, and this concept of an electronically conducting membrane has also been used by Evans to explain localised attack on steel due to a discontinuous film of magnetite. [Pg.187]

Some drains act on the body by changing the cellular environment, either physically or chemically. Physical changes in the cellular environment include changes in osmotic pressures, lubrication, absorption, or the conditions on the surface of the cell membrane An example of a drag that changes osmotic pressure is mannitol, which produces a change in the osmotic pressure in brain cells, causing a reduction in cerebral edema A... [Pg.7]

Surface-modified electrodes were used for prevention of high overpotentials with direct oxidation or reduction of the cofactor, electrode fouling, and dimerization of the cofactor [7cj. Membrane electrochemical reactors were designed. The regeneration of the cofactor NADH was ensured electrochemically, using a rhodium complex as electrochemical mediator. A semipermeable membrane (dialysis or ultrafiltration) was integrated in the filter-press electrochemical reactor to confine... [Pg.198]

Bacteria have been Implicated in the formation of N-nitroso compounds under a wide variety of conditions representing both vitro and vivo situations Mechanisms of participation and/or catalysis Include a) decrease of the pH of the system, b) reduction of nitrate to nitrite, c) adsorption of amine onto the cell surface or cytoplasmic membrane, d) actual enzymatic formation. The literature of the field will be reviewed and experimental evidence which tests the above mechanisms will be presented ... [Pg.157]

It proves possible to anchor catalysts of H2 evolution to the outer and inner surface of the vesicle membrane. These catalysts are finely dispersed (10-20 A in diameter) metal Pt or Pd particles formed via reduction of appropriate salts in vesicle suspension (see [15, 16] and refs, therein). Among the viologen-type electron carriers a promising one is p-bis (1,2,5-triphenyl-4-pyridil)benzene which possesses reduction potential low enough for water reduction at neutral pH. Recently, using this mediator we succeeded in H2 evolution conjugated with PET... [Pg.40]

Mustain WE, Kepler K, Prakash J. 2007. CoPd, oxygen reduction electrocatalysts for polymer electrolyte membrane and direct methanol fuel cells. Electrochim Acta 52 2102-2108. Nagy Z, You H. 2002. Applications of surface X-ray scattering to electrochemistry problems. Electrochim Acta 47 3037-3055. [Pg.311]


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