Nano-permeable membranes

NishiyamaN,YamaguchiM, KatayamaT, HirotaY, Miyamoto M, Egashira M, Ueyama K et al. Hydrogen-permeable membranes composed of zeolite nano-blocks. J Membr Sci 2007 306(1-2) 349-354. 

Amouroux, S. C., Heider, D. and Gillespie Jr., J. W. (2010), Permeability estimation of nano-porous membranes for nonwetting fluids . Journal of Porous Media, 13(4) , 19-329. 

Physical Methods. Physical methods are divided into two general approaches. The pesticide is entrapped within a physical structure either at a molecular or micro-domain level or the pesticide in the form of a reservoir is enclosed within a polymeric envelope (2). In the first approach, the pesticide is mixed with the polymer (or other material with high energy density) to form a monohthic structure or matrix. Release is normally through diffusion through the matrix or dissolution and erosion of the matrix. In the second approach, structures are based upon a reservoir of the pesticide enclosed by the polymer, from nano-scale up to centimeter-sized devices. The shapes of these devices are varied and include spherical, such as microcapsules, and laminar or layered structures with the reservoir bounded by permeable membranes. These membranes provide a permeable barrier which controls the release rate. Other mechanisms of release include capsule rupture and erosion of the membrane. 

Improved bioavailability. More than 40% of the NCEs (new chemical entity) discovered have good membrane permeability but poor aqueous solubility (i.e.. Biopharmaceutics Classification System II). By formulating the NCE in solution inside a Softgel (e.g., lipid based) or in micro/nano emulsion, the solubility and hence the bioavailability of the compound may be improved. ... 

It has been reported [22] that micro/nano surface reactive layers introduced on the surface of oxygen ion transport membranes enhanced the oxygen permeability of dense oxygen-permeable perovskite-type ceramic membranes, Lao.7Sro.3Gao.6Feo.403 6. The results also showed that the oxygen permeation flux is influenced by the surface area of the surface-reactive layer. 

Lee KS, Shin TH, Lee S, Woo SK. Enhancement of oxygen permeability by the introduction of a micro/nano surface reactive layer on the oxygen ion transport membrane. J Ceram Process Res. 2004 5(2) 143-7. 

Fully dispersed nano-size zeolitic imidazolate frameworks embedded in PBI have been used in gas separation membranes [26]. The loading with these specific nanoparticles overcomes the low permeability of neat PBI. The membranes exhibit high transparency and mechanical flexibility, and an enhanced... 

An important event of recent years in membrane science was the discovery of a new phenomena observed when nano-particles are added into (mainly high permeability) polymer matrix references to these pioneer works can be found in chapters of Section II Nanocomposite (Mixed Matrix) Membranes. So it is not surprising that several presentations at ICOM2008 dealt with such systems. Golename et al. (Chapter 6) investigated the Systran that contained perfiuorinated polymers and surface-fiuorinated zeolites as nano-additives. Perfiuorinated polymer AF2400 with nano-additives was also the object... 

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