The activities of the Textile scientific department cover the study of fabrics (identification of fibers, colorants, deterioration), as well as preservation issues for textile collections (climate, exposure, storage). It should be noted that a significant part of the department’s work is also focused on infestations (identification, treatment, prevention). The department also participates in various professional training courses on preservation-restoration (Master’s Degree in Preservation-Restoration of Cultural Property, National Heritage Institute) and trainee internships.
- Chemical and Structural Characterization of Metal Threads
Spectrometric analysis methods such as X-ray fluorescence (XRF) spectroscopy or scanning electron microscopy coupled with energy dispersive X-ray micro-analysis (SEM/EDXA) are methods that are now commonly applied to the analysis of metal threads. These physical methods essentially rely on the properties of the interactions between the materials and electromagnetic radiation. They are user-friendly methods that offer excellent sensitivity, enable multi-element analysis and make it possible to determine the composition of the metal. They are not, however, able to take into consideration local heterogeneity, such as the distribution of different phases.
A more suitable way of characterizing metal strips is to undertake a metallographic analysis using polished sections. Such analyses yield not only a more precise definition of the material’s structure, the manner in which its constituent elements are arranged and local heterogeneity, but also information regarding any modifications that the material has undergone during thermal or mechanical processes during its manufacture.
- Studies on Combatting Infestations
Because of the unique associations established between pheromones, their role in reproduction, their impact at low doses and the fact that they are innocuous, pheromones are potentially a biological weapon in the battle against insect pests. They are most widely used to lure insects into traps.
Trapping the common clothing moth, Tineola bisselliella, using artificial pheromone bait, has proven particularly effective. There are now several commercial brands available on the market. In order to characterize the different products, studies were carried out regarding: the kinetics of volatile compound diffusion; and the insects’ behavior in real conditions during trapping at the Mobilier National.
- Hygrometry Regulation System using Porous Polymer Membrane Electrolysis
The hygrometry regulation system using porous polymer membrane electrolysis is a self-contained system, requiring neither additions nor evacuation of liquid water, since the humidity is controlled in a gaseous state. The device consists of an anode and a cathode connected to a DC generator and separated by a conducting polymer membrane. At the heart of the apparatus is the proton exchange membrane which – influenced by the difference in electric potential applied to the electrodes – enables, on the anode side, water vapor molecules to be broken down into hydrogen ions and oxygen gas (O2). Only hydrogen ions can pass through the membrane, to be released on the cathode side where they re-combine with oxygen from the air to form water vapor again (Fig 4). Climate monitoring performed on the glass case of the “Shrine of Saint Capresius” (Saint-Vrain, Essonne), which has been equipped with this system since 2009, has demonstrated the value of this technology in regulating hygrometry within a sealed enclosure located in non-controlled climate conditions (Fig 5). Today the project is centered on laboratory testing of the way the system works in controlled environments.
- Mohamed Dallel | Conservation scientist - Research engineer