Membranes Publications

Porter, Mark C., Handbook of Industrial Membrane Technology, 1990 (Noyes Publications, Park Ridge, NJ) p. 174. 

Figure 11.18 Schematic diagram of an in-line SPE unit for CE using (a) polyester wool frits to hold the sorbent, or (b) a paiticle-loaded membrane. Reprinted from Journal of Capillary Electrophoresis, 2, A. J. Tomlinson and S. Naylor, Enhanced performance membrane preconcenti ation-capillary electrophoresis-mass spectiometi y (mPC-CE-MS) in conjunction with ti ansient isotachophoresis for analysis of peptide mixtures, pp 225-233, 1995, with permission from ISC Teclmical Publications Inc.

As indicated earlier, heavy contamination can be buried, sealed or removed. Burying of the material should be well below the root growth zone, and this is normally taken as 3.0 m below the final ground-surface level. Sealing for heavy contamination to prevent vertical or lateral leaching through groundwater flow can be with compacted clay or proprietary plastic membranes. Removal from site of the contaminants is normally only contemplated in a landscaped scheme where the material, even at depth, could be a hazard to public health directly or phytotoxic to plant life. 

The explicit mathematical treatment for such stationary-state situations at certain ion-selective membranes was performed by Iljuschenko and Mirkin 106). As the publication is in Russian and in a not widely distributed journal, their work will be cited in the appendix. The authors obtain an equation (s. (34) on page 28) similar to the one developed by Eisenman et al. 6) for glass membranes using the three-segment potential approach. However, the mobilities used in the stationary-state treatment are those which describe the ion migration in an electric field through a diffusion layer at the phase boundary. A diffusion process through the entire membrane with constant ion mobilities does not have to be assumed. The non-Nernstian behavior of extremely thin layers (i.e., ISFET) can therefore also be described, as well as the role of an electron transfer at solid-state membranes. 

As is the case with pure bubble columns and gas-operated loop reactors, most bioreactors in technical use are aerated with oxygen or air. Reactors with pure surface aeration, such as roller bottles, shake flasks and small stirred reactors or special reactors with membrane aeration, are exceptions. The latter are used for the cultivation of cells and organisms which are particularly sensitive to shearing (see e. g. [28 - 29]). The influence of gas bubbles in increasing stress has been described in many publications (see e.g. [4, 27, 29, 30]). In principle it can be caused by the following processes ... 

Modified from Olkonnen VM, Ikonen E Genetic defects of intra-cellular-membrane transport. N Eng J Med 2000343 1095. Certain related conditions not listed here are also described in this publication. l-cell disease is described in Chapter 47. The majority of the disorders listed above affect lysosomal function readers should consult a textbook of medicine for information on the clinical manifestations of these conditions. 

There are no convenient databases for liposome log P values. Most measured quantities need to be ferreted from original publications [149,162,376,381-387,443], The handbook edited by Cevc [380] is a comprehensive collection of properties of phospholipids, including extensive compilations of structural data from X-ray crystallographic studies. Lipid-type distributions in various biological membranes have been reported [380,388,433]. 

Kharaka, Y.K., Retention of dissolved constituents of waste by geologic membranes, in Symposium on Underground Waste Management and Artificial Recharge, Braunstein, J., Ed., publication 110, International Association of Hydrological Sciences, 1973, pp. 420-435. 

Quantitative analytical treatments of the effects of mass transfer and reaction within a porous structure were apparently first carried out by Thiele (20) in the United States, Dam-kohler (21) in Germany, and Zeldovitch (22) in Russia, all working independently and reporting their results between 1937 and 1939. Since these early publications, a number of different research groups have extended and further developed the analysis. Of particular note are the efforts of Wheeler (23-24), Weisz (25-28), Wicke (29-32), and Aris (33-36). In recent years, several individuals have also extended the treatment to include enzymes immobilized in porous media or within permselective membranes. The important consequence of these analyses is the development of a technique that can be used to analyze quantitatively the factors that determine the effectiveness with which the surface area of a porous catalyst is used. For this purpose we define an effectiveness factor rj for a catalyst particle as... 

The water-soluble vitamins generally function as cofactors for metabolism enzymes such as those involved in the production of energy from carbohydrates and fats. Their members consist of vitamin C and vitamin B complex which include thiamine, riboflavin (vitamin B2), nicotinic acid, pyridoxine, pantothenic acid, folic acid, cobalamin (vitamin B12), inositol, and biotin. A number of recent publications have demonstrated that vitamin carriers can transport various types of water-soluble vitamins, but the carrier-mediated systems seem negligible for the membrane transport of fat-soluble vitamins such as vitamin A, D, E, and K. 

Lackner, K.S., West, A.C., and Wade, J.L., Ion Conducting Membranes for Separation of Molecules, U.S. Patent Publication Number WO2006113674, 2006. 

In 1977, Parshall and co-workers published their work on the separation of various homogeneous catalysts from reaction mixtures.[46] Homemade polyimide membranes, formed from a solution of polyamic acid were used. After reaction the mixture was subjected to reverse osmosis. Depending on the metal complex and the applied pressure, the permeate contained 4-40% of the original amount of metal. This publication was the beginning of research on unmodified or non-dendritic catalysts separated by commercial and homemade membranes. 

Step 3 Biocompatibility. The biocompatibility of selected polymers, identified in Steps 1 and 2, were evaluated by implanting flat membranes into a C57/B16 mouse (Jackson Labs, Bar Harbor, ME). The membranes and capsules were implanted at various internal sites or in the back tissue under the skin. The results of these tests are not reported herein and will be discussed in a subsequent publication. They do, however, have important implications as to the ultimate selection of a polymeric system. 

Direct fluorination of polymer or polymer membrane surfaces creates a thin layer of partially fluorinated material on the polymer surface. This procedure dramatically changes the permeation rate of gas molecules through polymers. Several publications in collaboration with Professor D. R. Paul62-66 have investigated the gas permeabilities of surface fluorination of low-density polyethylene, polysulfone, poly(4-methyl-1 -pentene), and poly(phenylene oxide) membranes. 

Figure 2. Atomic force microscopy images showing the surface of a rhesus monkey erythrocyte membrane. Damage, such as formation of humps on the peripheral surface and pits in other parts, results from the interaction with virions of the canine parvovirus, (a) edge of erythrocyte (b) pits on membrane surface. (Source http //www.ntmdt.ru/ publications/download/211.pdf, Reproduced with permission from Dr Boris N. Zaitser)...

Publications summarizing the results of studies on the effect of pigments on the skin and mucous membrane (conjunctiva of eyes) of rabbits describe similar observations. These sources refer to pigments as trade products which may contain auxiliaries (Table 37). 

Menziani, M.C., Fanelli, F., Cocchi, M. and De Benedetti, P.G. (1996) The heuristic-direct approach to quantitative structure-activity relationship analysis of ligand-G protein coupled receptor complexes, in Membrane Protein Models Experiment, Theory and Speculation (ed. J. Findlay), Bios Science Publications, pp. 113-131. 

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