Polymer slime

Biofilm is commonly found within the labyrinthine waterways of cooling systems and is primarily composed of mixed populations of bacterial cells, immobilized within a fibrous matrix of ionic polymer (slime). 

Abbreviations LM light microscopy, EPS extracellular polymer slime, FM fluorescence microscopy, SEM scanning electron microscopy, S M environmental scanning electron microscopy, 7 M transmission electron microscopy, CSLM confocal scanning laser microscopy, AFM atomic force microscopy... 

Flocculants and surfactants (qv) are used frequently as filter aids, particularly when slimes are present or when the particles to be filtered are very fine and difficult to filter. Low molecular weight polymers are more commonly used. These form small, dense floes which provide higher cake porosity. 

Precipitate formation can occur upon contact of iajection water ions and counterions ia formation fluids. Soflds initially preseat ia the iajectioa fluid, bacterial corrosioa products, and corrosion products from metal surfaces ia the iajectioa system can all reduce near-weUbore permeability. Injectivity may also be reduced by bacterial slime that can grow on polymer deposits left ia the wellbore and adjacent rock. Strong oxidising agents such as hydrogen peroxide, sodium perborate, and occasionally sodium hypochlorite can be used to remove these bacterial deposits (16—18). 

Slime layers are a mixture of bacterial secretions called extracellular polymers, other metabolic products, bacteria, gases, detritus, and water. Commonly, 99% of the slime layer is water, although much silt and debris may also become entrapped in it. 

Slime is a network of secreted strands (extracellular polymers) intermixed with bacteria, water, gases, and extraneous matter. Slime layers occlude surfaces—the biological mat tends to form on and stick to surfaces. Surface shielding is further accelerated by the gathering of dirt, silt, sand, and other materials into the layer. Slime layers produce a stagnant zone next to surfaces that retards convective oxygen transport and increases diffusion distances. These properties naturally promote oxygen concentration cell formation. 

When the polymers are cross linked using borax, you get the children s toy Slime. 

Injectivity can be reduced by bacterial slime which can grow on polysaccharides and other polymer deposits left in the wellbore and adjacent rock. Strong oxidizing agents such as hydrogen... 

Work on the fermentation of microbial polysaccharides started in the mid 1970 s, with the aim of producing improved polymers. Many thousands of samples were screened for microorganisms which produced viscous polymers. Out of over 2000 such slime producing organisms isolated, only one, identified as a Pseudomonas species, now NCIB 11592, seemed to produce a polymer with interesting new properties. 

Using an aqueous solution of polyvinyl alcohol, you will prepare a cross-linked polymer, commonly known as Slime. ... 

In addition to murein, bacterial polysaccharides include dextrans—glucose polymers that are mostly al 6-linked and al 3-branched. In water, dextrans form viscous slimes or gels that are used for chromatographic separation of macromolecules after chemical treatment (see p.78). Dextrans are also used as components of blood plasma substitutes (plasma expanders) and foodstuffs. 

Wise, E.T. and S.G. Weber, A simple partitioning model for reversibly cross-linked polymers and application to the poly(vinyl alcohol)/borate system ("slime"). Macromolecules, 1995. 28(24) p. 8321-8327. 

Where hyperbolic towers are used in process industry, it is not uncommon to find corrosion-inducing, sulfate-reducing bacteria under the silt, or as part of biofilm slimes. Use of problem-specific polymers and biocide programs can be of considerable benefit in these cases. 

Production of biofilms. The bacteria implicated in corrosion may begin their lives on a metal surface as a scatter of individual cells. As the biofilm matures, however, the organisms are usually found as individuals or in colonies embedded in the matrix of a semicontinuous and highly heterogeneous biofilm (Figure 6.33). (Dexter)5 Microorganisms start on the surface from scattered individual bacteria to thick, semicontinuous films or colonies (slime or polymer) which can influence corrosion. 

Actin (Mr = 41,800) is widely distributed in eukaryotic cells, often being the most abundant protein, and commonly making up about 10 percent of the total cell protein. The protein is highly conserved with only 17 of the 375 amino acids different between slime mold actin and rabbit muscle actin. Monomeric actin is usually referred to as globular or G-actin while the polymer, filamentous actin, is termed F-actin. 

Slime layer of organic polymers varies in thickness with eige of the cell and other environmental conditions stores food and binds food and other bacteria into food. 

Solid formulations for sustained drug release may contain mesogenic polymers as excipients. The mesogenic polymers form a matrix, which is usually compressed into tablets. Some of the most frequently used excipients for sustained release matrices include cellulose derivatives, which behave like lyotropic liquid crystals when they are gradually dissolved in aqueous media. Cellulose derivatives such as hydroxy-propyl cellulose or hydroxy-propylmethyl cellulose form gel-like lyotropic mesophases in contact with water, through which diffusion takes place relatively slowly. Increasing dilution of the mesophase with water transforms the mesophase to a highly viscous slime and then to a colloidal polymer solution. 

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