Responsive surfaces protection system

In modern practice, inhibitors are rarely used in the form of single compounds — particularly in near-neutral solutions. It is much more usual for formulations made up from two, three or more inhibitors to be employed. Three factors are responsible for this approach. Firstly, because individual inhibitors are effective with only a limited number of metals the protection of multi-metal systems requires the presence of more than one inhibitor. (Toxicity and pollution considerations frequently prevent the use of chromates as universal inhibitors.) Secondly, because of the separate advantages possessed by inhibitors of the anodic and cathodic types it is sometimes of benefit to use a formulation composed of examples from each type. This procedure often results in improved protection above that given by either type alone and makes it possible to use lower inhibitor concentrations. The third factor relates to the use of halide ions to improve the action of organic inhibitors in acid solutions. The halides are not, strictly speaking, acting as inhibitors in this sense, and their function is to assist in the adsorption of the inhibitor on to the metal surface. The second and third of these methods are often referred to as synergised treatments. 

Overall, this work highlights how quantum chemical methods can be used to study tribochemical reactions within chemically complex lubricant systems. The results shed light on processes that are responsible for the conversion of loosely connected ZP molecules derived from anti-wear additives into stiff, highly connected anti-wear films, which is consistent with experiments. Additionally, the results explain why these films inhibit wear of hard surfaces, such as iron, yet do not protect soft surface such as aluminum. The simulations also explained a large number of other experimental observations pertaining to ZDDP anti-wear films and additives.103 Perhaps most importantly, the simulations demonstrate the importance of cross-linking within the films, which may aid in the development of new anti-wear additives. 

LPDI nanoparticles are homogenous, self-forming spheres between 100 and 200 nm in diameter that are formed from the spontaneous rearrangement of a lipid bilayer around a polycation condensed DNA core. The LPDI particles (lipopolyplexes) have benefits over lipoplexes, which are composed of liposomes and DNA. Homogenous particles are formed during preparation and thus allow a more consistent production of particles, as required by the FDA for clinical use. The LPDI particles also have a lower toxicity associated with them as opposed to lipoplexes, which can generate severe systemic inflammatory responses, most likely to the increased DNA content on the surface of the particles. The internalization of DNA inside the LPDI also has a benefit of DNA protection. The DNA is not nearly as accessible to nuclease attack and mechanical stress. Therefore, a lower quantity of DNA is used because it is protected inside of the LPDI for delivery. 

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