Surface decontamination experimental

The experimental simulation of a chemical bum (Figs. 3.84 and 3.85) is stated on a corrosive such as some IM soda in contact for 3 min with the semipermeable membrane representing the cornea. It favorably shows the time gained, thanks to a solution that physically and chemically helps the pH of the aqueous humor to get back to the safe zone. Here, the point is not only to show the mechanical draining effect at the surface of the membrane/comea (which quickly restores the pH to a normal value), but also to show how the internal decontamination of a corrosive is important and difficult. The internal decontamination will deal with the amount of corrosive that might have already penetrated into the anterior chamber of the eye. 

The basic experimental studies of the interactions between organophosphorus compounds and metal oxide surfaces have been carried out intensively during the last several years. Metal oxides, such as MgO, AI2O3, FeO, CaO, Ti02 a-Fe203, ZnO, and WO3, are currently under consideration as destructive adsorbents for the decontamination of chemical warfare agents [46, 47], For example, several studies have addressed adsorption of dimethyl methylphosphonate (DMMP) (a widely used model compound for the simulation of interactions of phosphate esters with a surface) on the surface of these metal oxides [48-60], In most of these works, the authors have observed that, at first, DMMP is adsorbed molecularly via hydrogen... 

Work surfaces are to be decontaminated after use or after any spill of viable materials. Doors to animal rooms open inward, are self-closing, and are kept closed when experimental animals are present. 

Alex and Janice studied the resistance to crack and craze growth in PC and PMMA in the presence of several surface-active solvents including a component of the universal chemical warfare decontaminant, DS2 (Alex and Janice 1989). A static dead weight-loading apparatus is used for experimentation, and LEFM is used to interpret craze initiation and crack propagation via compact tension specimens. Results reflect relationships based on solubility parameters of the solvents and the polymers. 

During R D on decontamination process, it is often difficult to obtain samples that are representative of the materials to be decontaminated. In many instances problems associated with accessibility and radioactivity prohibit the use of specimens taken from actual nuclear facilities. Often decontaminations involve the dissolution of adherent oxide films that have grown, over the course of many years, on metal surface. Practically, the laboratory synthesis of such films is often impossible. For this reason, film dissolution processes are often investigated by performing studies on the dissolution of bulk oxides and clean metal surface. Great care must be exercised when adopting this approach, it must be determined that the metals and oxides used are truly representative of those required. Particularly for the oxide, this necessitates extensive chemical and physical characterization. Further, even if the individual phases are representative of the film components, it is necessary to confirm experimentally that the data obtained yields an acceptable model of film dissolution. 

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