Magnetic membranes

Fig. 18.4 Schematic representation of a cross section of a corrosion tubercle A) Surface crust, B) magnetic membrane,...

FIGURE 43.9 Magnetic membrane proposed for biological separation. (Reprinted from Barbie, M., J. Magn. Magn. Mater., 249, 357, 2002. With permission from Elsevier.)... 

Khoo and Liu [4] presented results on the design, fabrication, and testing of a novel, micromachined magnetic membrane microfluidic pump. Their pump composed of a magnetic... 

Khoo M, liu C (2000) A novel micromachined magnetic membrane microlluidics pump. Proceedings of the 22nd annual EMBS international conference, Chicago, 23-28 July 2000, pp 2394—2397... 

Elat ethylcellulose membranes of thickness 28-80 pm and EC magnetic membranes of thickness 90-202 pm (depending on magnetic powder granulation and on the amount of added powder) were used. Both types of films were made by casting. The solution in... 

The membranes were removed from the Petri dish (with some distilled water), and dried at 40 °C. For membranes with dispersed magnetic powder, the permeation measurements were carried out before (just powder) and after magnetization (magnetic membranes). Magnetic induction of this field was approximately of 2T. Teslameter FH 54 was used for measurement of magnetic induction. The membranes were stored in an desiccator under vacuum conditions. We have also tested polyphenyleneoxide (PPO) membranes [40-44], courtesy of B. Kruczek (Faculty of Engineering, University of Ottawa, Canada). 

Figure 9.7 Downstream absorption permeation curve - a schematic view. Reprinted with permission from Journal of Membrane Science, On the air enrichment by polymer magnetic membranes by A. Rybak, Z. j. Crzywna and W. Kaszuwara, 336, 1-2, 79-85, Copyright (2009) Elsevier Ltd...

If 5 = Du the diffusion is supposed to be ideal Fickian , unless there are some hidden processes, like a drift, which are not included in this simple protocol [31]. In fact, in case of the magnetic membranes the presence of a drift is almost certain. 

To understand properly air enrichment by the magnetic membranes we had to estimate the values of Aco, i.e. an equilibrium concentration of the air components (no sorption experiments have been carried out). Since Aco is not measured (in this chapter), we have to calculate it. The most realistic value of Aco can be estimated by comparing its values obtained by the different methods. 

Figure 9.10 Downstream absorption permeation curves for various polymer and magnetic membranes. Points marked as squares, magnetic membrane with B = 1.25mT stars, magnetic membrane with B = 0.79mT triangles, magnetic membrane with B = O.SOmT asterisk, plane EC membrane...

Air Enrichment by Polymeric Magnetic Membranes 175 Table 9.4 Drift coefficients estimated via eq. 9.26 for different magnetic induction... 

It is clear that the idea of magnetic membranes works. There are, however, some obstacles that depend on the kind of membrane used, especially when the stronger magnetic... 

Figure 6.4 (A) Photographs of swollen hydrogel containing CMC/cellulose/Epichlorohydrin and SEM cross-section of the freeze-dried hydrogel sample (B) SEM image of a decorated nanofibiil and large magnetic membranes (20 cm diameter) prepared by vacuum filtration of the decorated nanoiibril...

E. Sourty, D. H. RycUi, and R. H. Marchessault, Chciracterization of magnetic membranes based on bacterial and man-made cellulose. Cellulose 5, 5-17 (1998). 

J. A. Marins, B. G. Soares, H. S. Barud, and S. J. L. Ribeiro, Flexible magnetic membranes based on bacterial cellulose and its evalution as electromagnetic interference shielding material. Mater. Sci. Eng. C 33, 3994-4001 (2013). 

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