Polypropylene membrane

Hoechst Celanese Corp. Tonen Corp. Asahi Chemical Industries Mitsubishi Ube Industries Ltd. Pall RAI Celgard membranes made of polypropylene, polyethylene, and combinations Setela membranes made of polyethylene HiPore membranes made of polyethylene Exepol membranes made of polyethylene Polypropylene membranes Polyethylene membranes... 

To avoid this damage great efforts were made to improve the cultivation systems. Feder and Tolbert [5] developed special stirrers with low shear damage and Lehmann et al. [6] replaced gas bubbling through indirect aeration by diffusion of oxygen through porous polypropylene membranes. 

For the preparation of the triazine membranes, the entire solid support (cellulose or polypropylene membrane) was treated with a 5 m solution of the corresponding amine in l-methyl-2-pyrrolidinone (NMP) and a 1 m solution of cesium phenolate in dimethyl sulfoxide (2 p L of each at one spot) and subsequently heated in a domestic microwave oven for 3 min. After washing the support successively with... 

The frits in the cartridges are intended to retain stationary phase material in the separation channels (columns) while permitting the passage of the mobile phase during separations. Each frit is constructed from a permeable polypropylene membrane with an average pore size smaller than the... 

In lithium-based cells, the essential function of battery separator is to prevent electronic contact, while enabling ionic transport between the positive and negative electrodes. It should be usable on highspeed winding machines and possess good shutdown properties. The most commonly used separators for primary lithium batteries are microporous polypropylene membranes. Microporous polyethylene and laminates of polypropylene and polyethylene are widely used in lithium-ion batteries. These materials are chemically and electrochemically stable in secondary lithium batteries. 

Piletsky SA, Matuschewski H, Schedler U, Wilpert A, Piletska EV, Thiele TA, Ulbricht M. Surface functionalization of porous polypropylene membranes with molecularly imprinted polymers by photograft copolymerization in water. Macromolecules 2000 33 3092-3098. 

This simple mass transfer model based on simplified film theory has been proposed to describe the process of facilitated transport of penicillin-G across a SLM system [53]. In the authors laboratory, CPC transport using Aliquat-336 as the carrier was studied [56] using microporous hydrophobic polypropylene membrane (Celgard 2400) support and the permeation rate was found to be controlled by diffusion across the membrane. 

Vacuum apparatus and 0.45-prn polytetrafluoroethylene (PTFE) or polypropylene membrane... 

Vacuum fdter through 0.45-pm PTFE or polypropylene membrane. 

The support membrane is soaked in the prepolymerisation mixture consisting of functional monomer, crosslinker and template. An MIP layer is formed on or in the porous support by in situ photo or thermal polymerisation of the monomer mixture. This was first demonstrated by Haupt and coworkers on an amino acid specific MIP synthesised in the pores of a polypropylene membrane. Composite membranes... 

Figure 3.6 Flow schematic of a melt extruder system used to make polypropylene membranes by template leaching [13]...

Polymer precipitahon by cooling to produce microporous membranes was hrst developed and commercialized by Akzo [33,37], which continues to market microhltration polypropylene and poly(vinylidene fluoride) membranes produced by this technique under the trade name Accurel . Flat sheet and hollow fiber membranes are made. Polypropylene membranes are prepared from a solution of polypropylene in N, A-bis(2-liydroxyethyl)tal lowamine. The amine... 

A comparable strategy is applied to obtain compounds with a pronounced biological selectivity. By treatment of a porous NH3+-containing polypropylene membrane with the sulfate of dextran, a material for convenient removal... 

Acetylcholineesterase and choline oxidase Sensors were developed consisting of a Clarke oxygen electrode modified by superposition (over the polypropylene membrane of the electrode) of a dialysis membrane on which AChE and ChO were immobilized. Both formats are based on the conversion of the substrate to choline which is oxidized in the presence of choline oxidase causing a reduction in p02 which is detected by the electrode. Free choline is measured with a similar electrode with only choline oxidase immobilized on the membrane. Calibration graphs were rectilinear upto 90 pM choline and upto 120 pM acetylcholine. Results were presented for the analysis of tissue extracts and pharmaceutical formulations. [115]... 

A peptide library can be synthesized using the SPOT synthesis technique to form a low-density peptide spot array (e.g., 25 spots/cm ). In this method, different peptides are synthesized in situ as low-density arrays on cellulose membrane or paper (8). The volume of Fmoc-amino acids and coupling reagents dispensed creates a specific SPOT size that determines both the scale of reaction and the absolute number of peptides that can be arranged on an area of a membrane. Cotton (another form of cellulose) and polystyrene-grafted polyethylene film segments also have been used as solid supports. Recently, polymeric membranes that are chemically, mechanically, and thermally more stable have been developed, which include hydroxy-functionalized PEG acrylate polypropylene membranes and an amino-functionalized ester-free PEG... 

The above list of solid supports is by no means exhaustive. Many others have been proposed and evaluated for use in peptide synthesis, including polypropylene membranes, cotton, controlled-pore glass beads, polyethylene sheets, and others. 

Radiometer pOz electrode, type E 5046 consists of a platinum cathode (20 /am diameter) and silver-silver chloride reference electrode placed in an electrochemical solution behind a 20 /am thick polypropylene membrane. A polarizing voltage of about 650 mV is applied. The polarographic current is about 10 " A per mm Hg of oxygen tension at 38°C. Zero current is lower than 10 A, response time less than 60 sec at 38°C 99% of full deflection. The PO2 electrode is used with the pH-Meter 27 GM or the Astrup Micro-Equipment, in conjunction with the Oxygen Monitor. The scale can be calibrated to the range 0-100 mm Hg p02. Thermostated cells provide measurements at constant temperature of volumes down to 70 /al. The small volume makes this cell useful to measure the PO2 of capillary blood. The cell is supplied with accessories for blood sampling. 

Fig 1. 1 pmol Parathyroid Hormone Fragment 39-68 (PHF), lOpmoI Pigeon Heart Cytochrome C (PHC), 10 pmol Bovin Serum Albumin (BSA) in saturated sinapinic acid matrix, desorbed from a. Polyethylene Membrane 113-2 b. Polypropylene Membrane 1222 c. Type 61 Disposable IR Card d. C8 Extraction Disk e. C18 Extraction Disk. 

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