Macromolecular bridging

Evidence for Macromolecular Bridging. Our current concept of the mechanism of RBC aggregation is that it results from macromolecular bridging (2) (see Figure 18). In this model the macromolecules in the suspending medium are adsorbed to the RBC membrane surface. When RBCs are brought into close proximity of each other by thermal motion,... 

Figure 18. Diagram showing the mechanism of RBC aggregation by macromolecular bridging (2)...

The Macromolecular Bridging Energy. Based on the model of cell aggregation by macromolecular bridging, Eb for a cell pair is a function of the number of bridging macromolecules between these cells (ra), the number of bonds with cell surface per bridging molecule (bm), and the interaction energy per bond (eb)... 

Balance Between Macromolecular Bridging Energy and Electrostatic Repulsive Energy. In the absence of externally applied forces, the net aggregation force per unit cell surface area (difference between the macromolecular bridging force per unit area (electrostatic repulsive force per unit area ([Pg.32]

Figure 5.8 Schematic representation of three alternative effects of the adsorption of stiff hydrocolloid polymers on the surface of spherical emulsion droplets, depending on the hydrocolloid concentration and the nature of the hydrocolloid-protein interaction (a) A sterically stabilized system, b) an emulsion gel, and (c) a system flocculated by macromolecular bridging (Dickinson, 2003).

Sulfur Dyes. These dyes are synthesized by heating aromatic amines, phenols, or nitro compounds with sulfur or, more usually, alkah polysulfides. Unlike most other dye types, it is not easy to define a chromogen for the sulfur dyes (qv). It is likely that they consist of macromolecular stmctures of the phenothiazone-thianthrone type (72), in which the sulfur is present as (sulfide) bridging links and thiazine groups (1). 

Metallophosphazenes are a new type of macromolecule designed to bridge the gap between polymers and metals. Although still at an exploratory stage of laboratory development, they may provide access to electronically-conducting polymers, magnetically-active polymers, macromolecular catalysts, electrode mediator systems, or polymers crosslinked by metal atoms. 

As the number of non-bridging oxygen or sulphur atoms increases, the average length of the macromolecular chains decreases. The chemical reaction symbolised in (4.2) is strongly exothermic, and the mixing enthalpies are of the order of some hundreds of kilojoules. The magnitude... 

For the above reaction to occur, the aromatic nuclei in compound 1 should carry activating groups, such as hydroxyl, alkoxy, or fused ring aromatics". As a result of reaction with BF3 and phenol, the macromolecular structure of coal should undergo rupture at the aliphatic bridges, and these bridges are transferred to phenol molecules to produce bisphenols. Analysis of the bisphenols should provide information on the aliphatic bridges present in coal structure. 

Sulfur dyes are water-insoluble, macromolecular, colored compounds which are produced by bridging aromatic amines, phenols, and amino phenols with sulfur and/or sodium polysulfide [16], These dyes are of little interest for dyeing paper. Only C.I. Sulphur Black 1 (36), the most important dye of all in terms of volume, is used for special paper dyeings. 

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