A system for continuous monitoring of atmospheric corrosivity has been developed. An electronic unit measures and records changes in the electrical resistance of a thin metal track applied on an insulating substrate. If the metal corrodes, the effective cross sectional area of the track decreases and the electrical resistance increases. Sensors made of silver, copper, iron/steel, zinc, lead, tin, aluminium, bronze, and brass at thicknesses from 50 nm to 250 m were tailored for environments with different corrosivities. The developed technology proved capable of providing high sensitivity, allowing for real-time corrosion monitoring even in low-corrosive indoor cultural heritage facilities. Laboratory tests showed good reproducibility with the standard deviation of parallel measurements at less than ±20% for metals which corrode uniformly in the tested environments. Several examples selected from a broad testing programme in partner museums, libraries, and other institut ions show successful applications of the logger system for characterization of air quality control in indoor locations, during transport and in temporary exhibitions; assessment of new buildings and storage facilities; and fundamental studies of optimal conservation and storage procedures. A first outline of a classification system for lead, which is particularly sensitive to the presence of carboxylic acids, is given. The technique has a large potential as an independent method for monitoring air quality in facilities displaying and storing valuable objects of cultural heritage

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High electrostriction and relaxor ferroelectric behavior in proton-irradiated poly(vinylidene fluoridetrifluoroethylene) copolymerIt is shown that the Curie point of the ferroelectric vinylidene ftuoride-trifluoroethylene copolymer can be shifted to the low temperatures by electron radiation. This effect was studied by in situ dielectric measurements as a function of the dose and of the irradiation temperature.An additional effect of the irradiation, in particular when performed at high temperature, was to noticeably decrease €'. We also have studied annealing at temperatures around the melting point and shown that most of the irradiati.on damage was nonreversible and cumulative whereas part of it could be annealed. We have shown that it was apparently impossible to shift the Curie temperature lower than a limit temperature of the order of 0 0c. We discuss this effect and suggest the hypothesis of a competition with the glassy transition occuring in this temperature region.

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