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1.
A medieval wooden panel chamber was rediscovered during reconstruction of the Tetzelhouse in the Saxon town of Pirna. Ceiling and walls are made from 600-year-old fire wood panels fitted together. The complete removal of layers (limewash, plaster, glue and dirt) from the wall panels was the precondition for conservation of the wood panels and for the restoration of the wooden panel chamber. The cleaning was carried out with a pulsed Nd:YAG laser after basic investigation of ablation mechanisms of the layers on the old wood. All layers of the different materials were removed both from the normal surface and out of depressions and woodworm holes with a special range of laser parameters, without damaging the wood. Within this range of parameters the laser cleaning is a self-limiting process. The health hazard from emitted waste products were determined and checked with work place measurements. The laser cleaning of the wooden wall panels was completed in March 1999. A uniform visual impression of all panels was obtained with a warm wooden colour tone.  相似文献   

2.
The use of phase change materials (PCMs) in civil buildings as an effective thermal energy storage solution has been well documented in literature and proven in the field. When applied to Cultural Heritage, PCMs’ technology needs to be adapted to specific requirements. Besides the important objectives of economic return and human comfort, the indoor microclimatic conditions have to be suitable for conservation purposes. The application of PCMs’ technology to Cultural Heritage has been investigated within the European MESSIB (Multi-source Energy Storage System Integrated in Buildings) project. Firstly, several methodologies of incorporation of PCMs in different materials were studied and tested. The thermal properties of gypsum panels and silicon coatings incorporating micro-encapsulated PCMs in the form of powder and emulsion were analysed in the laboratory. Then, PCMs incorporated in gypsum panels in contact with a wooden panel were tested and their effect on the thermal behaviour of the wooden panel was evaluated under thermal cycles in a climatic chamber. PCMs incorporated in silicon coatings in contact with a painting were also tested. Moreover, gypsum panels containing PCMs were tested in the S. Croce Museum in Florence, Italy, where the microclimatic monitoring has shown thermal conditions potentially dangerous for the works of art preserved. The research performed both in the laboratory and on the field confirmed the effectiveness of the PCMs as thermal storage solutions, but also gave evidence on an important drawback when the material incorporating PCMs is in direct contact with an object of art.  相似文献   

3.
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4.
The effects of a Q-switched Nd:YAG laser irradiation on a group of supports, painted with six different inorganic pigments, was investigated. The pigments were chosen from among the most utilized on painted historical surfaces: red ochre, yellow ochre, chromium green, ultramarine azure, white chalk and carbon black, and they were distempered with two binders – linseed oil and gypsum – on primed wood panels. The pigments were characterized by means of X-ray diffraction and Fourier transform infrared spectroscopy. Chromatic characteristics, chemical composition and surface morphology of the painted layers were investigated before and after the laser irradiation. Three different fluences were used to detect the correlation between laser parameters and changes in painting layer characteristics.  相似文献   

5.
Since 2004 an international research group of Wood Technologists has been given by the Louvre Museum the task of analysing the hygro-mechanical state of the Poplar (Populus alba L.) panel on which Leonardo da Vinci painted his “Mona Lisa”, namely verifying the appropriateness of the thermo-hygrometric conditions in its exhibiting showcase, where the microclimate is actively controlled, and assessing the potential consequences of any hypothetical fluctuation. In order to acquire data about the mechanical behaviour of the panel, and to feed and calibrate appropriate simulation models, the team has not only set up a continuous monitoring by means of automatic equipment, but has also performed manual measurements on the occasion of the annual openings of the showcase where the masterpiece is conserved and exhibited. This paper reports about techniques used for estimating the forces acting between the wooden panel and its frame (the châssis-cadre), and their location, such data being of primary importance for evaluating the panel's internal stresses. The contact forces have been calculated on the basis of the local contact pressures, imprinted on a pressure-sensitive foil as a range of saturation values of the colour developed in the contact areas. The forces calculated as above have also been compared with the contact forces between the panel's back face and the crossbeams pressing it against the châssis-cadre, which have been measured by means of a load cell. As could be expected, the results from so different techniques do not strictly coincide; however the agreement is fairly good.  相似文献   

6.
Maintaining the microclimatic parameters at the desired value is essential for artefacts preservation. In order to control the status of the microclimatic parameters, a continuous monitoring of the indoor environmental provides conservators, curators, restorers, and lenders with an exact knowledge of the microclimatic conditions under which the works of art are kept. Moreover, the monitoring results give important information in order to make adequate changes to the control strategy of microclimatic parameters. From this point of view, monitoring is an essential tool to develop an actual preventive control programme aimed at maintaining the optimal microclimatic conditions for preservation. As a consequence, long-term monitoring has to be applied to prevent deterioration of works of art. The widespread opinion that a correct approach to the topic of microclimate control for artefacts preservation is not only and necessarily to provide buildings with sophisticated environmental control systems, but mainly to investigate the actual environmental dynamics and, before any structural intervention, to define the compatibility between the climate control potentials and the preservation requirements, has become more and more firm among the experts. Monitoring also allows to verify the capacity of the “building and Heating, Ventilation and Air Conditioning (HVAC)” system to maintain the desired thermo-hygrometric values within the operating conditions. To this aim, the Italian Standard UNI 10829 (1999) defining monitoring, elaboration and analysis of the microclimatic data as supporting actions for artefacts preservation, led to the need of a long-term monitoring and of a statistical approach to the data management. The approach proposed by the Italian Standard has been recently adopted by a European Standard (EN 15251, 2007). In accordance with the Standards mentioned above, in this paper an operational procedure to assess the thermo-hygrometric quality in museums is firstly synthetically presented and than applied to a case study. In particular, the procedure is developed in order to define the thermo-hygrometric quality level of the exhibition areas in the large museum complex of “Santa Maria della Scala” in Siena (Italy) during the international temporary exhibition “Duccio. La nascita della pittura senese” (“Duccio. The birth of Sienese Painting”).  相似文献   

7.
This paper describes some results from an experiment carried out regarding a procedure to be adopted for temperature and R.H. monitoring of indoor spaces designed for exhibiting events, such as museums and similar institutions. The monitored data employed in this study has been collected by the Department di Ricerche Energetiche ed Ambientali of the Università degli Studi di Palermo in co-operation with the Regional Gallery ''Palazzo Abatellis'' of Palermo. The study analyses a simple method for characterising the environmental quality of museums so as to ensure the optimal conservation of works of art. This methodology is based on the procedure (where thermal and hygrometry parameters are concerned) proposed by an Italian standard rule. A new technique, firstly applied to the industrial environment, based on the passive reactive monitoring of proper coupons is also proposed for monitoring air quality in museums. The methodology adopted, has been applied to two survey campaigns which were carried out at a distance of 5 years. This shows the two aspects of thermal-hygrometry and levels of indoor air quality aimed at preserving works of art. The future developments of this work are oriented towards the definition of guidelines in support of those responsible for the conservation of works of art and improvements in the quality of environments for artwork conservation and for the comfort of visitors through the use of proper HVAC systems.  相似文献   

8.
The impact of electric overhead radiant heaters on the microclimate, air flows, transport and deposition of suspended particulate matter (SPM) was monitored between March 2004 and March 2005 in the historic churches of Saint Michael Archangel in Szalowa and Saint Catherine in Cracow (Poland). The measurements show that although irradiation at the floor level increases temperature and reduces relative humidity in the interior of the church, the effect out of the heated zone and for the surfaces sheltered from irradiation is very limited, i.e. their extent is comparable with natural fluctuations inherent to the local climate of the church. The radiant heaters proved to generate little convectional flow of the air. Therefore, the heating system was not found to increase the concentration of SPM indoors; in particular, no re-suspension of particles already present in the church was observed. This work has demonstrated that the overhead radiant heaters are capable of providing localised heat to the areas where people congregate without adversely affecting painted walls and the works of arts displayed in churches. Care, however, should be taken that sensitive works of art are not exposed to the direct infrared radiation.  相似文献   

9.
The application of a new class of organogels as cleaning tools for painted surfaces is described. It combines some of the most attractive features of cleaning liquids and normal gels while diminishing the deleterious characteristics of both. Thus, the ‘latent’ gellant, polyethyleneimine (PEI), reacts with CO2 at room temperature in solutions of several organic liquids to produce an ammonium carbamate form (PEICO2). This charged species organizes itself into 3D polymer networks which immobilize the liquids as gels. The properties of the original solution (i.e. a free-flowing liquid) are re-established immediately after addition of a small amount of a weak acid which displaces the CO2 molecules and makes the PEI chains positively charged. The visual changes are substantiated by rheological analyses. Results from analytical tests to determine the utility of these gels as cleaning tools for painted surfaces of historical and artistic interest, have been obtained from contact angle and FTIR measurements as well as visual comparisons of the surfaces before and after application of the gels. The analyses indicate that the PEICO2-based organogels were very effective in removing different surface patinas from painted supports. A surface layer of dammar was completely removed from a test canvas with oil paint, an aged painting from the XIX century, and a XV century oil-on-wood panel attributed to Mariotto di Cristoforo. Finally, a surface acrylic polymeric resin (used in a restoration performed during the 1960s) was also successfully removed from Renaissance wall paintings decorating the Santa Maria della Scala Sacristy in Siena, Italy. The isothermally rheoreversible gel approach described in this work represents a new, highly versatile, and very efficient method for removing aged surface patinas from works of art.  相似文献   

10.
In the interdisciplinary domain of conservation science, a critical and selective eye is required in order to allow researchers to choose the most effective combination of analytical techniques for each project and, more importantly, to process and analyze the resulting volume of diverse data. The current essay attempts to combine a more traditional workflow for the examination of painted objects with techniques borrowed from the domain of computer science in order to yield the maximum amount of information and make that added knowledge more accessible to the researcher. The project was approached as a case study, regarding a post-Byzantine icon. Three-dimensional digitization with a laser scanning system, X-ray radiography and optical microscopy were applied for the determination of several structural characteristics of the painted surface and the icon's state of preservation. Multispectral imaging was used for the collection of surface spectral data, which were subsequently processed by means of cluster analysis in a novel approach to map the composition of the painted surface. Finally, micro-X-Ray Fluorescence (μ-XRF) was chosen as the primary source for surface pointwise elemental composition data while Fourier Transform Infrared Spectroscopy (FTIR) and Gas Chromatography coupled with Mass Spectroscopy (GC-MS) provided additional assistance in the characterization of materials based on their molecular structure. A custom platform was developed to address the issue of multilevel visualization and assessment of the data, designed to act as a tool for viewing and combining the acquired information. Via this integrated approach valuable information regarding the icon was revealed, including the verification of a prior conservation attempt and partial overpainting, the recording and quantification of the warping of the wooden panel and, finally, the identification of the constituent materials and their spatial distribution.  相似文献   

11.
The European project Friendly-Heating (FH): comfortable to people and compatible with conservation of artworks preserved in churches addressed the problems caused by the continuous or intermittent heating of historic churches, which disturbs the microclimatic conditions to which the building and the artworks preserved inside have acclimatised. As thermal comfort and the preservation of artworks often conflict with each other, a balance between the two needs is necessary. The proposed heating strategy is to provide a small amount of heat directly to people in the pew area while leaving the conditions in the church, as a whole, undisturbed. This novel heating system is based on some low-temperature radiant emitters mounted in a pew to provide a desirable distribution of heat to the feet, legs and hands of people occupying it. Due to little heat dispersion, this novel system not only significantly reduces the risk of mechanical stress in wooden artworks and panel or canvas paintings, fresco soiling and cyclic dissolution-recrystallization of soluble salts in the masonry, but is energy-efficient. The detailed environmental monitoring was conducted in the church of Santa Maria Maddalena in Rocca Pietore, Italy over a 3-year period to verify the performance of the novel heating system in comparison to the warm-air system that was active earlier in the church. The methodology and results of this comprehensive and multidisciplinary study were included in three draft standards of the European Committee for Standardisation intended for use in the study and control of environments of cultural heritage objects.  相似文献   

12.
Over the last years, there was an increasing interest in keeping suitable microclimatic conditions for the preservation of artefacts: the artefacts preservation requirements may diverge from those of the museums visitors, willing to enjoy the works of art in a situation of psycho-physical wellness. The HVAC designers and engineers will have then to cooperate closely with the curator, in order to define a compromise between conflicting environmental performance requirements. In particular at the stage of air-conditioning system design or retrofit, it is extremely important to carry out a series of preliminary analysis to evaluate and monitor the existing environmental conditions and to anticipatory simulate and predict the post-intervention conditions. To this aim, advanced fluid-dynamic investigation tools (Computational Fluid Dynamic [CFD] techniques) enable to deal with the specificity of such topics and provide a useful decision-making support.  相似文献   

13.
Wood identification is a basic information that should interest any wooden artefact. This typically involves invasive sampling, but sometimes sampling is unattainable either because of the object typology or because it is difficult to obtain authorizations. In the present study, reflected light microscopy potential as a non-invasive identification tool for wooden cultural artefacts is assessed on a number of marquetry furniture and small wood carvings. In more than one half of the 13 examined cases accurate wood identification was possible, while the remaining cases yielded information of diagnostic value, making it possible to exclude several potential candidate species. In a number of cases the use of optical filters improved the visibility of character states. Shape and orientation of surfaces influenced the visibility of microscopic characters. The study confirms that reflected light microscopy is a valuable tool for non-invasive wood identification. In many cases it is able to support accurate identification, in others it can anyway provide important information, useful to help decision about supposed species, or to limit the invasiveness of possible further analysis by addressing them on specific features.  相似文献   

14.
The removal of a brass-based paint (purpurin) used in painting gilded wood to cover losses of gold leaf, represents today a difficult task to conservators, who may have to resort to toxic chemical solvents in order to clean the painted surface. This action, due to its nature, is unsuitable for both the conservator and the artwork itself. In this study, a Q-switched Nd:YAG laser system outputting 1 064 nm (infrared), 532 nm (visible, green) and 266 nm (ultra-violet) radiation was used to study the interaction of these wavelengths in a gilded sample surface painted with purpurin. All tested wavelengths interacted differently with the tested surface and, also, the several layers that form the gilded surface (purpurin, varnish and gold) showed different interactions to each wavelength. The ultra-violet radiation (266 nm), in a multi-pulse mode at low fluences, was found to be the most efficient wavelength in cleaning the painted gilded surface.  相似文献   

15.
The most frequent dating methods of wooden artefacts are briefly introduced and discussed. Each of them shows merits and shortcomings. Therefore, an integrated approach of different techniques sometimes allows overcoming specific difficulties.The dating of a wooden support of a precious panel painting through a detailed xylological analysis and the joint use of dendrochronological and radiocarbon dating techniques is proposed. While any single dating technique demonstrated ineffective, the simultaneous use of several approaches in the study of the artefact led to excellent results in terms of both reliability and resolution, thus contributing to the inclusion of this painting in a specific historical period. On the basis of the performed dating, supported by the features of the panel and by a chemical-stratigraphic analysis of paint fragments, the artwork cannot be attributed to Cesare da Sesto.  相似文献   

16.
The focus of this work is the wood polychrome model of the church of S. Maria della Consolazione in Todi, an artefact whose author and historical events are not completely known except a general reference to the construction period of the church (1508–1607 AD). In this study, original and additional materials were examined in order to provide a deeper understanding of the painting and assembly techniques, and a greater awareness of how well preserved the object is, as well as an analysis of previous preservation and conservation interventions. The samples from the painted surfaces were examined by means of micro-Raman spectroscopy, fourier transform infrared (FTIR) spectrometry and internal microstratigraphic analysis. Thin sections of the wood samples were examined under an optical transmission light microscope in order to identify the botanical species. The results shown in this paper suggest the possibility that the original painted layers are made of calcium carbonate white, red ochre and indigo and they were applied by protein binder without any ground layer. Some non-original pigments were found on the model surface like Prussian blue and chrome yellow. Concerning wood components, poplar was characterized both in the original and non-original parts of the model whereas pine species were detected only in the restoration elements.  相似文献   

17.
To assess the possible effects of mechanical loading on the conservation of historical wooden musical instruments, a research project was carried out on the violin Guarneri “del Gesù” (1743), known as the “Cannone”. This paper refers to the results obtained by studying the deformations to which a violin is subjected after being tuned, with special attention to the viscous and mechano-sorptive behaviour (as in a concert environment for example). The amount of viscoelastic creep was quantified under normal tuning conditions, and the mechano-sorptive creep was quantified using a dead mass resulting in 55% of the elastic deformation obtained after tuning. The viscoelastic and mechano-sorptive deformations were clearly observed. These deformations were completely recovered once the violin was unloaded, demonstrating that this violin structure is appropriately dimensioned for the applied stresses.  相似文献   

18.
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19.
Five optical analyses of a given work of art are presented, using multispectral imaging, optical coherence tomography, goniophometry, UV-fluorescence emission spectroscopy and diffuse reflectance spectroscopy. All these methods are non-destructive, contactless, and implementable in situ. They all lead to results in quasi-real time. The multispectral camera allows imaging of the whole painting with very high definition and recording of 240 millions of spectra. Optical coherence tomography allows local 2D and 3D imaging with in-face and in depth stratigraphies inside the painting with a micrometric accuracy. It allows the evaluation of the pigment volume concentration inside a layer, the measurement of the thickness of one or two varnish layers, the detection and measurements of gaps inside the paint layer, the depth of varnish micro-cracks. Goniophotometry allows the measurement of the upper surface state of the painting in different locations, by quantifying the mean slope of the facets making up the surface. UV-fluorescence emission spectroscopy allows the identification of the resin, the binder and the ageing state of varnishes by use of databases of reference varnishes. Diffuse reflectance spectroscopy leads to pigment, pigment mixture and dye identifications again by use of databases. The three last methods are implemented with the same portable multi-function instrument. It allows time saving, locations on request in front of the artwork and easy use by non-scientists. Each instrument is described with its protocol and accuracy. The studied painting is a portrait of a lady painted by the Austrian artist Franz Strotszberg, chosen for its several restorations. The five kinds of results are successively detailed, analysed and compared between themselves. It is shown that the different results are complementary and their crosschecking brings thorough information. For example, the shape of the network of varnish micro-cracks detected on the surface with the multispectral camera is added to the measurement of their depth with optical coherence tomography. Another example allows connecting two different surface states of the upper varnished surface measured by goniophotometry with the identification of these varnish with UV-fluorescence and with their thicknesses measured with optical coherence tomography.  相似文献   

20.
Samples from the wooden backing of Piero della Francescaˈs 15th century painting Pala of Saint Bernardino were analyzed in order to determine the type of adhesive used for the preparation of the panel. Wood, tow and drop-shaped glue fragments were collected from different sections of the reinforcements and the material connecting the planks. Samples were hydrolyzed and the resulting free amino acids were derivatized and analyzed by gas chromatography. On the basis of amino acid composition and D/L ratios of aspartic acid, two types of proteinaceous adhesives were identified: collagen from animal-skin glue (used in restoration works) and casein (the original adhesive, prepared from cheese and lime). Only a few samples were found to consist of pure casein or collagen, the others being a mixture of the two adhesives. The results are consistent with historical evidence indicating the use of caseinate as an adhesive at the time of the painterˈs activity.  相似文献   

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