As early as the second half of the 19th century, awareness arose of the possible alterations that exhibit certainly conditions could induce on the objects on display (Russell-Abney report) [1].As is well-known, light definitely is one of the primary damage factors: it can produce different effects, such as colour alteration, colour fading, mechanical damage, embrittlement, and so on. Naturally, light is also necessary so that visitors can enjoy works of art; therefore, curators and conservators have to find a compromise Inhibitors,Modulators,Libraries to make it possible for visitors to benefit from it while guaranteeing long life for the artefacts.Other factors that can potentially constitute a threat for works of art are temperature Inhibitors,Modulators,Libraries and relative humidity, together with their abrupt changes.
In fact, under the effect of temperature the reaction rate of many chemical reactions increases, causing serious structural alterations in objects. Moreover, thermo-hygrometric Inhibitors,Modulators,Libraries fluctuations can induce deformations in non-isotropic materials, or detachments of parts consisting of different materials. On the other hand, high humidity can favour Inhibitors,Modulators,Libraries micro-organisms and moulds that can attack the supports in which these develop. Moreover, owing to variations in humidity, mechanical changes and deformations can occur in hygroscopic materials, such as wood panels, while hygroscopic hydrated minerals in natural history museums can be altered.Artefacts can be also seriously damaged by atmospheric pollutants, often also present indoors, such as NOx, SO2, O3, organic vapours and cleaning agents, just to mention a few.
These gases can produce not only colour changes, Inhibitors,Modulators,Libraries but also corrosion (mainly in metals) and chemical and/or mechanical alterations.All the above factors act not only individually, but also cooperatively, so that the effect of one factor Inhibitors,Modulators,Libraries is enhanced by the presence of others: Inhibitors,Modulators,Libraries for example, Anacetrapib light and temperature, light and pollutants, pollutants and humidity. In some cases, specific definitions have been introduced to take into account synergistic effects. For example, in referring to light and photo-induced Inhibitors,Modulators,Libraries phenomena, we can mention the concept of equivalent light dose. This term is used to define the light dose capable of producing, in a given material exposed to light and other uncontrolled environmental agents, the same effect (e.
g. colour change) as the one induced in the same material by exposure to a known light-source and in Drug_discovery controlled environmental conditions [2].
To summarize, for a correct conservation policy, it is important not only to monitor the single physical or chemical parameter, but also to evaluate the impact dilution calculator of the whole environment. This is not a simple task. In fact, many devices are available that make it possible selleck inhibitor to measure temperature/relative humidity (thermo hygrographs), light (lux meters), powders, selected pollutants, etc.