Membrane modifications composites

In both situations the interaction of the medium inside the pore with the pore wall (1) is increased (2) or changed which affect the transport and separation properties (surface diffusion, multilayer adsorption) and/or help overcome equilibrium constraints in membrane reactors. Membrane modifications can be performed by depositing material in the internal pore structure from liquids (impregnation, adsorption) or gases. Several modification possibilities are schematically shown in Figure 2.3. Some results obtained by Burggraaf, Keizer and coworkers are summarized in Table 2.7. Composite structures on a scale of 1-5 nm were obtained. 

Miscellaneous membrane modification, film modification, antifouling compositions, analytical agents... 

Engelhard, V.H., Esko, J.D., Storm, D.R., and Glaser, M., Modification of adenyl cyclase activity in LM cells by manipulation of the membrane lipid composition in vivo, Proc. Natl Acad. Sci., 73, 4482, 1976. 

Membrane Lipid composition modification Increased liposome stability,... 

Hsiao LL, Howard RJ, Aikawa M, Taraschi TF. Modification of host cell membrane lipid composition by the intra-erythrocytic human malaria parasite Plasmodium falciparum. Biochem. J. 1991 274 121-132. 

The erythrocyte-bound malaria parasite acquires host lipids by diverse methods and transports to the area of celluar growth. There they are remodeled significantly to meet the parasite s needs, including phospholipid head group alteration, modification of the fatty acid molecular species composition of certain phospholipids, and transformation of the erythrocyte membrane lipid composition in both infected and uninfected cells. 

Although the hydrophobic surface of nylon membranes may be improved by hydrolysis or chemical modification, composite polyamide membranes are preferred in chromatographic applications. Klein et al. [42] prepared polyamide microporous membranes by modification of terminal amino groups. Covalent binding of a polyhydroxyl-containing material to the polyamide membrane increases the density... 

To show the potential of the impedance measurements for determining a membrane, modifications associated with both manufacture effects, in terms of changes in the material and/or structure, and working process effects, such as fouling or age, were considered. This chapter will describe the research on commercial and experimental membranes from different materials and with diverse structures (porous, dense, and composites) used in filtration processes, charged membranes, or those presenting working modifications. The manbranes used to demonstrate the potentiality of IS are ... 

Over the last 50 years, pervaporation (PV) has been developed as a technology with particular use in dehydration of solvents, alcohol/water separation, VOC removal from water, and separation of organic mixtures. Chapter 9 reviews the improvement of PV performance using membrane modification with a discussion on different strategies for surface modification of synthetic polymeric membranes and composite polymer/inorganic membranes. 

It has also been postulated that this strategically located enzyme may be regulable in non-neural tissues (Lamb Fallon, 1974). Control of PA phosphatase may yield deep changes in membrane lipid composition, mainly when the modification of the biosynthetic pathway affects minor lipids such as IPG (Michell et al., 1976). 

Silvius, J.R. Thermotropic phase transitions of pure lipids in model membranes and their modification by membrane proteins, in P.C. lost and O.H. Griffith (eds.), Lipid-Protein Interactions. Vol. 2, Wiley, New York, (1982), pp. 239-281. Somerville, C. Direct tests of the role of membrane lipid composition in low-temperature-induced photoinhibition and chilling sensitivity in plants and cyanobacteria. Proc. Natl. Acad. Sci. U.S.A. 92 (1995), 6215-6218. 

Kfen, V., Pazoutova, S., Rezanka, T. and Sajdl, R (1988a) Chlorophenoxyacids influence ergot alkaloid production in Claviceps cultures by modification of cell-membrane lipid composition. Abstract Book, 2nd Internal. Symp. Overprod. Microbial Products, Ceske Budejovice, Czechoslovakia, July 3-8, 1988, 156. 

CMC, they caused changes in the bacterial outer membrane protein composition yet did not affect the LPS component. Chang et al. (2009) demonstrated that the cell-surface hydrophobicity was enhanced by the acciunulation at the cell surface of different fatty acids during growth on hydrocarbon in R. erythropolis NTU-1. A significant correlation between the modification of the cell surface by saponins and the degree of hydrocarbon biodegradation was reported by Kaczorek et al. (2008). 

Verheul, A., Russell, N.J., VantHof, R., et al. (1997). Modifications of membrane phospholipid composition in nisin-resistant Listeria manacytagenes Scott A. Appl Enviran Micrabial 63, 3451-3457. 

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