Synthetic Surfaces

Typical static friction coefficients are given in Table 1. These data demonstrate that the absolute traction values for synthetic surfaces are satisfactory in comparison with natural turf, provided that shoes with the appropriate surfaces are employed. Synthetic surfaces by virtue of their constmction are to a degree directional, a characteristic which, when substantial, can significantly affect both player performance and ball roU. This effect is evident in a measurement of shoe traction in various directions with respect to the turf—pile angle. Some traction characteristics are directiy affected by the materials. 

Many modifications of MacConkey s medium exist one employs a synthetic surface-active agent in place of bile salts. 

W. M. Krumbhaar, The Chemistry of Synthetic Surface Coatings, Reinhold, New York, 1937. 

The protein A (pA), antihuman serum albumin (a-HSA, M 150 kD), and human serum albumin (HSA, M 65 kD) were provided by Paradocs BV (Tiel, The Netherlands). The Herpes Simplex Virus type 1 (HSV-1) and anti-HSV-1 gG glycoprotein G monoclonal antibody (a-HSV-1 gG) were purchased from Virusys Corporation (Marriottsville, MD, USA). Bovine serum albumin (BSA, M 50 kD) was purchased from Sigma-Aldrich Chemie BV (Zwijndrecht, The Netherlands). Synthetic surface protein of Hepatitis-B virus generated in Hep-G2 cell-line (HEP G2, M 25 kD) was provided by BioMerieux BV (Boxtel, The Netherlands). Phosphate buffered saline (PBS) was used for all experiments. 

The factor that differentiates natural and synthetic surfaces is the endothelial layer. The layer is truly nonthrombogenic and is capable of repairing itself. While it can develop on synthetic material, its growth in humans is slow. One way of accelerating growth is to seed the synthetic material. 

The term bioadhesion refers to any bond formed between two biological surfaces or to a bond between a biological and a synthetic surface [44]. In the case of bioadhesive drug delivery systems, the term bioadhesion is typically used to describe the adhesion between polymers, either synthetic... 

Other synthetic surface reactions are reviewed elsewhere (Lamb, Gates, and Knozinger, 1988 Basset, Lefebvre, and Santini, 1998). 

For a variety of reasons, demand arose for synthetic surfaces on which games could be played or displays and physical exercises presented. In some instances, existing playing fields, bowling greens, and tennis courts were inadequate— perhaps occupied too fully and not always available when wanted. Grass surfaces could become worn, saturated with moisture, or eroded in places, so that time had to be set aside for their recovery. For some sports and pastimes there was also a requirement for all-the-year-round and all-weather facilities. 

These needs led in turn to investigation of ways of preparing synthetic surfaces so that in behaviour they would be very similar to natural lawn or turf. The factors examined in this connection included the heights to which sports balls would rebound, the resistance to balls rolled over the surface ( ball drag ), and the absorption of impact. All were found to depend largely on the method of construction of the synthetic surface, including its underlayers—the correct... 

Figure 51 Applying adhesive for a synthetic surface for sports events...

Becher and Becher (2) measured the spreading pressure, tt, of a series of surfactants on plant and synthetic surfaces. The surfactants were characterized by HLB (hydrophile-lipophile balance) values (3) similar to those of Jansen s adjuvants. The relationship between the spreading pressure and the contact angle can be expressed as tt = yL cos 0, where yL is the surface tension of the liquid and 6 is the contact angle between the liquid and a solid surface. Becher and Becher demonstrated that surfactants in their series which exhibited maximum spreading pres-... 

A Ithough the adsorption of polymers onto solid surfaces has been thor-oughly studied (I), relatively few studies can be found in the literature on the adsorption of proteins onto polymer surfaces. In 1905, Landsteiner and Uhliz (2) discussed the interaction of serum proteins with synthetic surfaces. Blitz and Steiner (3) showed that albumin adsorption onto solid surfaces increased with increasing albumin concentration and that adsorption was nearly irreversible. Hitchcock reported (4) that adsorption of egg albumin onto collodion membranes followed a Langmuir isotherm with maximum adsorption occurring near the isoelectric point. Later, Kemp and Rideal (5) reported that protein adsorption onto solids conforms with Langmuir adsorption. 

Like colloidal material, surfaces have complex-ing sites for trace elements and the same formalism as that described for colloids can be used. Understanding the partitioning of metals and more generally trace elements between water and solids is crucial for fundamental smdies on transport, bioavailability, and fate of trace elements in river systems. For example, the spatial and temporal trends of metal or radionuclide partitioning between dissolved and suspended sohds is a major issue for understanding and predicting the pathways of pollutants in the environment. As a consequence, an impressive literature focuses on experimental studies of trace-element adsorption/desorption on synthetic surfaces (mostly hydrous oxides). However, field-based studies aimed at assessing the importance... 

Table 2 Synthetic surface active emulsifying agents...

In some cases, the supported mononuclear metal complexes are precursors of catalysts formed during reaction. For example, MCM-41-supported [(=SiO)2Ta(=NH)(NH2)] and [(=SiO)2Ta(=NH)(NH2)(NH3)] [19] are formed by the reaction of [(=SiO)2TaH], [(=SiO)2TaH3], and NH3 (Fig. 19.2). These and other synthetic surface reactions such as the ship-in-a-bottle method are reviewed elsewhere [20, 21]. 

L. K. Wang, M. H. S. Wang, S. Yaksich, and M. L. Granstrom, Water treatment with multiphase flow reactor and cationic surfactants, J. Am. Water Works Assc. 70, 522-528 (1978). V. Kondratazicius, Removal of synthetic surface-active agents from waste waters of tanneries, Kozk. Obur. Prom. (USSR) 11, 18-18 (1969). 

Weatherburn, A S, Determination of the ionic type of synthetic surface active compounds , Can. Textile J., 71(16), 45, 1954. 

Kozarac, Z., B. Cosovic, and V. Vojvodic (1986), Effects of Natural and Synthetic Surface Active Substances on the Electrochemical Reduction of Cadmium in Natural Waters, Water Res. 20, 295-300. 

When natural phospholipids are the surfactant, the formed vesicles are termed liposomes. They are made of fragmented phospholipid bilayers in aqueous solution, and closed liposome structures encapsulate some aqueous solution within. Lipids are natural surfactants having two hydrocarbon tails per molecule and they behave similarly to synthetic surfac-... 

Goodman, S.L., S.L. Cooper, and R.M. Albrecht, Integrin receptors and platelet adhesion to synthetic surfaces. Journal of Biomedical Materials Research, 1993, 27, 683-695. 

Organics and Salt Rejection in Synthetic Surface Water Solutions... 

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