Hybrid membranes functional

Umeda, J Suzuki, M Kato, M Moriya, M. Sakamoto, W. Yogo, T. (2010). Proton conductive inorganic-organic hybrid membranes functionalized with phosphonic acid for polymer electrolyte fuel cell. /. Power Sources, 195, 5882-5888, ISSN 0378-7753. 

Controlled formation of three-dimensional functional devices in silica makes the hybrid membrane materials presented here of interest for the development of a new supramolecular approach to nanoscience and nanotechnology through self-organization, towards systems of increasing behavioral and functional addressabilities (catalysis, optical and electronic applications, etc.). 

Michau, M., Arnal-Herault, C., Caraballo, R., van der Lee, A. and Barboiu, M. (2007) Ionic pathways in dense and functionalized hybrid membranes, manuscript in preparation. 

Barboiu M, Cazacu A, Michau M, Caraballo R, Amal-Herault C, Pasc-Banu A (2008) Functional organic- inorganic hybrid membranes. Chem Eng Proc 47 1044—1052... 

The presenee of the positively-eharged nitrogen atom in the hybrid molecule provides for the antioxidant adherenee to the surface of a cell membrane and its fixation in a eertain place by means of the lipophilic long-chained alkyl fragment Ri. Sueh a stmcture ensures the targeted use of the antioxidant and favors the inhibition of pathological processes in eell, e.g. intensification of LPO and disorders of cell membranes functions. 

The OHLM systems, integrating reaction, separation, and concentration functions in one equipment (bioreactor), find a great interest of researchers in the last few years. A bioreactor combines the use of specific biocatalyst for the desired chemical reactions, and repeatedly or continuously application of it under very specific conditions. Such techniques were termed as hybrid membrane reactors. In biotechnology and pharmacology, these applications are termed as hybrid membrane bioreactors or simply bioreactors (see Table 13.11). Experimental setup of the bioreactor system is shown schematically in Figure 13.17. 

DNA end. A slightly different type of PNA consists of amino adds with nudeobases in their side chains. PNA bind strongly to complementary DNA and RNA sequences. The high metabolic stability renders PNA interesting for in-vivo applications. However, further modifications are required in order to make it suitable for treatment in eukaryotic cells because of a lacking diffusion across lipid membranes. PNA may be used in diagnostic techniques for the detection of specific DNA, as well as for site-specific labeling and hybridization of functional molecules to both DNA and RNA [T. Koch et al.. Nucleosides Nucleotides 1997,16, 1771 D. R. Corey, Trends Biotechnol. 1997, 15,224 E. Uhlmann, Biol. Chem. 1998,379,... 

Pandey and Shahi [98] prepared functionalized silica (sodium 2-formylbenzenesulfonatepolysiloxane [SBAPTS])-NSBC (modified CS derivative A,0-sulfonic acid benzyl CS, Figure 16.16) hybrid membranes by sol-gel technique followed by cross-linking using formaldehyde for pervaporation separation of water/ethanol azeotrope. The prepared hybrid membrane was assessed to be very suitable for the separation of water from azeotrope of water-ethanol with 5282 selectivity and 0.59 L/m h total flux at 30°C in ethanol/ water mixture (90 wt.%). 

Pandey, R. P. and Shahi, V. K. 2013. Functionalized sUica-chitosan hybrid membrane for dehydration of ethanol/water azeotrope Effect of cross-linking on structure and performance. J. Membr. Sci. 444 116-126. 

Wang ED, Zhao TS, Yang WW (2010) Poly(vinyl alcohol)/3-(trimethyl ammonium (propyl-functionalized silica hybrid membranes for alkaline direct ethanol fuel cells. Int J Hydrogen Energ 35 2183-2189... 

Shirosaki, Y, Tsuru, K., Hayakawa, S. et al. 2009a. Physical, chemical and in vitro biological profile of chitosan hybrid membrane as a function of organosiloxane concentration. Acta Biomaterialia 5 346-355. 

Two categories of methods are commonly used for organic and hybrid membrane characterization. The first ones, named static characterizations, are aimed at the description of the structure and texture of membranes while the second ones named dynamic characterizations describe membranes at work, in other words the transfer of fluids and solutes through the membrane top-layer. Both static an dynamic characterization methods are important for a thorough understanding of single mass transport and even of the additional functions of the membranes (contactor, reactor...). 

Of special interest are the concept of structure-directed function of hybrid materials and how to control their build-up from suitable units by self-organization. Toward this objective, new functional hybrid membrane materials can be anticipated that form selective patterns so as to enable efficient translocation events. This implies the search for hybrid soUd systems in which the molecular recognition-driven transport function could be ensured by a well-defined incorporation of specific receptors, covalently linked in a dense siloxane matrix. 

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