Non-removable surfaces

A generalized layout for a batch-type vacuum processing system is shown in Figure 3.9. The deposition chamber is comprised of removable surfaces, such as fixturing and substrates, and non-removable surfaces. 

The non-removable surface should be protected from film buildup, corrosion, and abrasion. This may necessitate the use of liners and shields in the system to protect the surface from the processing environment or minimize the need for cleaning of the non-removable surfaces. Such designs may be at the expense of attaining minimum pumpdown time . 

The interior non-removable surfaces of the vacuum system should be protected as much as possible from deposits from the deposition process. Removable liners and shields should be used wherever possible. 

Liner, chamber (PVD technology) A removable surface in a chamber used to collect vaporized material and prevent it from depositing on non-removable surfaces. See also Non-removable surfaces Vacuum surfaces. 

Non-removable surface (vacuum technology) A surface, such as a chamber wall, that is not easily removed and must be cleaned in place. See also Removable surface. 

The amount of bonded surfactant can be determined by simple techniques. A dissolution technique proved to be very convenient for the optimization of non-reactive surface treatment and also for the characterization of the efficiency of the treating technology [74,84]. First the surface of the filler is covered with increasing amounts of surfactant, then the non-bonded part is dissolved with a solvent. The technique is demonstrated in Fig. 11, which presents a dissolution curve of stearic acid on a CaC03 filler. Surface treatment is preferably carried out with the proportionally bonded surfactant (cioo)j this composition the total amount of surfactant used for the treatment is bonded to the filler surface. The filler can adsorb more surfactant (Cjnax)>but during compounding a part of it can be removed from the surface by dissolution or simply by shear and might deteriorate properties. 

Phosphorus extracted from sediment by NaOH has been related to non-occluded, surface-exchangeable, bioavailable forms (22). Hydrochloric acid extraction yields occluded phosphorus incorporated in hydrous metal oxides, carbonate and phosphate minerals of sediment. Hydroxylamine reagent specifically removes hydrous manganese oxides, while amorphous hydrous oxides of iron and aluminijm are removed by the oxalate reagent. Total available sediment phosphorus analyses includes sediment organic phosphorus components in addition to the inorganic portion determined by the selective extraction procedures. 

Biogenic PFe actually consists of two distinct pools, intracellular or biological Fe and surface-adsorbed or scavenged Fe (Flutchins, 1995). The latter has usually not been considered to be a true component of the cellular Fe quota, and a titanium (Ti) wash method (Hudson and Morel, 1989) has therefore been commonly employed to remove surface-bound Fe in radiotracer studies (Eldridge et al., 2004 Hutchins et al., 1999 Poorvin et al., 2004 Sunda and Huntsman, 1997 Sunda et al., 1991). However, the titanium reagent is itself heavily contaminated with Fe and so its use is questionable for non-radioactive measurements. 

A more sophisticated peel test can be used to check the degree of surface treatment, and a suitable procedure is detailed in BS 2782 method 310. Another wetting test uses a dye in nitroethane which will remain as an intact film for up to 30 s with a treated material. A non-treated surface will show coalescence and form globules rapidly once the item is removed from the test solution. 

The thick-film metallization process requires modest capital equipment and the process is relatively simple. Typical capital equipment for thick-film metallization includes a silk screening printer and a furnace for annealing and removal of the organic binder. This equipment is relatively modest in cost. In addition to silk screening on a flat substrate, thick-film techniques can be applied by dipping, spraying, or roller coating the non-flat surface [4], Thick-film techniques can also be applied in a continuous operation which can be cost effective. 

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