Cellulose gels

The ether is also used in paint, varnish and lacquer formulations. A recent development is the use of ethyl cellulose gel lacquers. These are permanent coatings applied in a similar way to the strippable coatings. They have been used in the United States for coating tool handles, door knobs and bowling pins. 

Brown, W Stilbs, P Lindstrom, T, Self-Diffusion of Small Molecules in Cellulose Gels using FT-Pulsed Field Gradient NMR, Journal of Applied Polymer Science 29, 823,1984. Brownstein, KR Tarr, CE, Importance of Classical Diffusion in NMR Studies of Water in Biological Cells, Physical Review A 19, 2446, 1979. 

Hydroxypropylguar gum gel can be crosslinked with borates [1227], ti-tanates, or zirconates. Borate-crosslinked fluids and linear hydroxyethyl-cellulose gels are the most commonly used fluids for high-permeability fracture treatments. This is for use for hydraulic fracturing fluid under high-temperature and high-shear stress. 

This correlation was found to be valid for solute diffusion in heparinized polyvinyl alcohol) and cellulosic gels [74], It was also found that the model is quite insensitive to the value of the parameter Y. As such, a value of unity was found to be a good approximation. 

Wronski [55] described a method to separate and resolve penicillamine from physiological fluids. To urine (100 mL) was added 60 g of (NH4)2S04, the solution was filtered, mixed with 2 g of Na2S03, and 1 mL of 0.1 M EDTA in 20% triethanolamine, and shaken with 5-20 mL of 0.01-0.06 M tributyltin hydroxide in octane for 5 min. A portion (5-8 mL) of the organic phase was shaken with 0.2 mL of HC1 in 20% glycerol solution. A portion of the aqueous phase (5-10 pL per cm of the strip width) was applied to cellulose gel, and electrophoretic separation was performed by the technique described previously. The thiol spots were visualized with o-hydroxymercuri benzoic acid-dithiofluorescein and densitometry with a 588-nm filter. 

Basler EA, Dadang S, Kondo K, Tanito M (2004) JP 2004201590 A2 20040722 Microbial cellulose gels, their manufacture, and use for food materials... 

Later the same research group claimed that, in the first step of the in situ synthesis scheme, ionic functional groups as such are not necessary for the introduction of ferrous ions into a cellulose matrix [161,162], This suggestion was made based on a comparative study of ferrite synthesis between a case with anionically modified cellulose materials and the other case with non-ionic cellulose gels, which included a never-dried bacterial cellulose (BC) membrane and a never-dried cellulose wet-spun filament or cast film (Lyocell) using N-methylmorpholin-N-oxide as the solvent. SPM proper-... 

FMC (1993). Avicel Cellulose Gel (.Microcrystalline Cellulose) General Technology. FMC Corporation, Philadelphia, PA Novagel Cellulose Gel, FMC Corporation, Philadelphia, PA. 

Cellulose Gel occurs as a fine, white or almost white powder. It is purified, partially depolymerized cellulose prepared by treating a// /za-ccllulose, obtained as a pulp from fibrous plant material, with mineral acids. It consists of free-flowing, nonfi-brous particles that may be compressed into self-binding tablets that disintegrate rapidly in water. It is insoluble in water, in dilute acids, in dilute sodium hydroxide solutions, and in most organic solvents. 

Catalase Activity, 791 Caustic Potash, 318 Caustic Soda, 364 gamma-CD, (S3)16 Cedar Leaf Oil, 94, 577 Cedar Leaf Oil, White, 94 Celery Oleoresin, 392 Celery Seed Oil, 95, 578 Cellulase, 132, 786 Cellulase Activity, 791 Cellulose Gel, 95... 

Cellulose Avicel, Methocel, Solka-Floc, Cellulose gel, Just Fiber Mayonnaise, salad dressings, frozen desserts, processed cheese, fried foods, sauces... 

Avicel PH- Celex-, cellulose gel Celphere Ceolus KG crystalline cellulose E460 Emcocel Ethispheres Pibrocel Pharma-cel Tabulose Vivapur. 

We used DEAE-cellulose gel column chromatography at subzero temperature in an ethylene glycol—water mixture to isolate the microsomal cytochrome P-450 in its stable form. The already known stabilizing effect of ethylene glycol and low temperature contribute to the stabilization of the enzyme. The preparation of rat liver microsomes and the assays were carried out as described earlier. The amount of phospholipid was measured by the method of Ames and Dubin (1960). 

In a study to simulate conditions in plaque-fluid during an acidic challenge, Lynch et al. [16] placed pre-formed subsurface enamel lesions in a series of acidified methyl cellulose gel systems. The initial calcium, phosphate and fluoride concentrations of the gels were adjusted by the addition of calcium chloride, potassium phosphate and sodium fluoride. Two combinations of calcium and phosphate concentrations (high and low Ca,Pi), three pH values (5.2,5.0 and 4.8) and four fluoride concentrations were used in a 2 3 4 factorial experimental design. Lesion mineral content was assessed radiographically before and... 

Lesions created in both bovine and human enamel, in an acidified methyl cellulose gel system, displayed many of the same qualitative trends [Lynch, unpubl. data]. After an initial period of approximately 3 days when dissolution was negligible, mineral loss was typically found at a series of discrete locations, with no apparent mineral loss between these pockets of demineralisation. Surface zones were typically poorly defined or absent. After 5 or more days, the isolated pockets had coalesced and lesions were uniform in terms of both depth and mineral loss across the bulk of the lesion body, with well-defined surface zones. When observed under polarised light, these initial pockets of demineralisation were very often coincident with Hunter-Schreger banding. This was particularly noticeable in bovine enamel. Shellis [64] reported variations in solubility related to enamel microstructure and suggested that structure/solubility relationships are likely to influence lesion formation. 

To make the white spot lesions, human premolars were coated with nail polish except for a 5-mm square on their buccal surfaces. This ensured that demineralization always occurred at a specific location. The samples were then immersed in 200 ml methyl cellulose gel with 200 ml lactic acid solution (pH 4.6) poured on top, but separated by a sheet of filter paper. The teeth were stored in this solution at 3 7°C for 14 days to allow the lesions to develop. After removal from the gel, the teeth were washed and sectioned through the center of the lesions to enable the cross-section of each lesion to be viewed. The two cross-sections created for each lesion were then mounted in a low temperature cure epoxy and polished to an optical finish using 1/4-micron grit (diamond paste). 

Putra A et al (2008) Tubular bacterial cellulose gel with oriented fibrils on the curved surface. Polymer 49(7) 1885-1891... 

Fab and Fab fragments may be purified by the various methods given in Section 7.1. The most popular techniques are chromatography on CM- or DEAE-cellulose, gel filtration (Tijssen and Kurstak, 1974) and affinity chromatography. 

Thickeners and other additives In some cases a gel coating for the multiple emulsion drops may be beneficial, for example polymethacryhc acid or carboxymethyl cellulose. Gels in the outside continuous phase for a W/O/W multiple emulsion may be produced using xanthan gum (Keltrol or Rhodopol), Carbopol or alginates. 

Any formal definition of a gel has been avoided, because its formulation would be difficult on the basis of external properties. By any criterion, a 1 % aqueous solution of agar does form a gel when it is cooled from 95 to 20°, whereas a 1 % solution of sucrose does not but properties may be so continuous between these extremes that any dividing line would be arbitrary. Most of this Chapter is concerned with fairly permanent network structures formed from polymer solutions. As a definition of gels, this description is incomplete. Some cellulose gels, and pastes of gelatinized, starch granules, would be excluded, because they are formed by limited dispersion of solids. In other words, an arbitrary choice will be made to focus on those gels that are dilute with respect to polymer, because the information available about them at the molecular level is more precise than for others. 

The implications of the existence of liquid crystals in water-soluble cellulosic gels has not been fully studied in the field of biological applications. In particular, the models developed for water transport in hydrogels do not consider the presence of mesophases. The same is true for solute (drug) release models... 

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