Aggression feasibility

And, finally, a remarkable study from the same group is on the feasibility of electrolytic ablation of tissue on a rat pancreas 85 it is worth mentioning that currently, there are no ablative techniques to treat pancreatic cancer in clinical use and this is an aggressive disease with less than 20% of patients suitable for a curative surgical resection. 

In the light of these experiences, simulations using the extremely acidic Shilbottle Grange spoil leachate waters as a sole precursor were not even attempted it is clear that such highly contaminated waters could only feasibly play a role in the evolution of mature Whittle waters through mixing with less aggressive waters. 

The CAAA of 1977 realized that the aggressive approach of CAAA 1970 could not be achieved within an economically feasible manner. Therefore, deadlines were postponed. The key initiative of the amendment was the regulation of ozone destroying chemicals. This... 

In batch processing aggressive reactants are, typically, diluted to prevent thermal overshooting and runaway. Even then they often are added drop-wise, to allow heat transfer to be adjusted to heat release. In some cases, this may take over half an hour or so. This unnecessarily prolongs processing time and, also, the reaction then is carried out for a considerable part under totally changing reactant concentrations (from zero to full-load content). Conversely, microreactors with their efficient heat and mass transfer have the potential to contact the full reactant load all at once . In addition, microreactors can cope with concentrated solutions or even piue liquid reactants. Several examples are known for which such all at once or solvent-free procediues are feasible in microreactors with reasonable selectivity, whereas the... 

The resistance of many metals and alloys to corrosion depends critically upon the presence of a thin (10-1000 A [168]) passive surface film [169]. In "aggressive environments, this film may become damaged locally via several processes, e.g. surface stress effects (either flow-induced [170,171] or as a result of anion adsorption [168]), the impingement of small particles on the surface [169], spontaneous depassivation [169]. Retention of the protective film by the metal only results if repassivation of the unprotected area is feasible compared with pit growth. 

The feasibility of an integrated photocatalysis-pervaporation process can be preliminarily evaluated by taking into account some characteristics of photocatalysis. In the typical appHcations of photocatalysis, the reagents, which are termed substrates in the common terminology of photocatalysis (Braslavsky et al., 2011), should be present in low concentrations in order to ensure the economy of the process. Therefore the system is not as chemically aggressive for the membrane, particularly if the pervaporation modules are kept in separate equipments. In this way, the membrane is not exposed to the radiation or to the photoactivated radicals, which are present only close to the surface of the photocatalyst, as long as it is illuminated, since the lifetime... 

The second method includes chemical treatment of the corrosive environment, for decreasing its aggressiveness, by changing its pH, salt and moisture content, existing microbes, and existing bacteria, when it is economically and technically feasible. 

When electrolyte treatment is a feasible strategy, there are two (interrelated) strategies (a) removal of the aggressive species and (b) the addition of inhibitors. 

A comprehensive literature review on the degradation of mechanical properties of structural materials exposed to liquid Pb and Pb-Bi is given in Ref. [16]. As reported in this reference most of the experiments have been performed in liquid Pb-Bi and the extension of these experimental findings to pure Pb cordd lead to incorrect estimations, since liquid Pb-Bi seems to be more aggressive than liquid Pb. Moreover, the main structural materials tested were the 9Cr ferritic/martensitic steel 791 and the austenitic steel AISI316. However, a generalization of the residts obtained in order to predict the behavior of other 9Cr ferritic/martensitic and austenitic steels is not feasible, since as, for instance, minor alloying elements in the steel impact the materials behavior in these liquid metals. 

On the other hand, just the mixing of REM ions with other compounds seems to be a feasible way to achieve the inhibition efficiency required in very aggressive media, for example acidic media. REM by themselves are not able to supply the inhibition efficiency required in many industrial applications. These mixtnres of inhibitors have produced various synergies between different compounds (cathodic/ anodic inhibitors, cathodic surfactant inhibitors). Promising results, discussed elsewhere in this book, show inhibitor effects that would not be possible through the use of these substances separately. So, synergism is an effective method to improve inhibitor efficiency, and to reduce the amount of the compound used. It is also an interesting way to extend the application of these inhibitors to acidic media. 

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