首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 234 毫秒
1.
Electronic speckle pattern interferometry (ESPI) is a well-known tool in cultural heritage diagnostics. It is also suitable to reveal cracks and debondings of tiles in ancient mosaics of Roman and Medieval age. This paper describes a portable electro-optic system as a diagnostic tool to evaluate the state of conservation of ancient mosaics. The proposed system is based on the integration of ESPI and local speckle correlation techniques. Some experiments have been carried out on real, ancient, mosaics in laboratory and in situ. The different features of each technique are outlined and a comparison with holographic interferometry is also given.  相似文献   

2.
The pictorial cycle “Teodelinda's Tales” at Monza Cathedral, painted by Zavattari and his sons in 1444–1446, has been investigated by optical and SEM-EDS microscopy and microFT-IR spectroscopy. Paint layers, gildings and other metallic decorations have been analysed to elucidate the execution technique, the state of conservation and the possible retouchings in consequence of deterioration processes. Organic binders, coatings and adhesives have been also identified especially by microFT-IR spectroscopy applied directly to the sampled powders or fragments and to their solvent–soluble fractions. The obtained data offer a correct and satisfactory knowledge of the original organic and inorganic materials and those used in the subsequent retouches and restorations, their state of conservation and the painting techniques (fresco, mezzo fresco and secco).The physico-chemical investigations allowed to identify the nature and sometimes the provenance of the employed materials (i.e. ultramarine blue pigments) and some decay markers, particularly useful in understanding and describing the cycle realised by the authors and the modifications suffered along the centuries, and also to propose an integrated methodology for the scientific study of the mural paintings.  相似文献   

3.
One set of samples from wall paintings of the Xth Regio of Italy containing green colours was analysed exploiting different spectroscopic techniques, aiming to identify the pigments used. The possibility to distinguish between glauconite and celadonite, the most common green pigments used in such paintings, was of particular interest. Samples of celadonite from Monte Baldo and glauconite from Belgium were considered as standard materials for comparison. The results obtained using FTIR, EDS, AAS, Colorimetry, Raman and EPR spectroscopies were compared for the identification of the green pigments.  相似文献   

4.
  相似文献   

5.
  相似文献   

6.
The microclimatic analysis of the Petrarca's tomb in Arquà Petrarca, Padua (Italy) was performed to assess the suitability of a closed environment located outdoors respect to the conservation requirements of heritage materials. Results showed that the thermo-hygrometric conditions inside the tomb were not suitable for the conservation of organic materials, like bones and wood. The orientation (north or south) was the main responsible for the different damage features of the two sides of the wooden case housing the human remains inside the tomb. Technical solutions were finally implemented to improve the conservation conditions, thus avoiding further damage.  相似文献   

7.
Nanolime dispersed in 2-propanol was extensively used for the consolidation of wall paintings. The knowledge of the advances of this methodology dealing with all the possible effects associated with the nanolime new material in conservation is fundamental to assess and improve the technique. In this paper, four different dispersions of Ca(OH)2 nanoparticles were characterised by Small Angle X-rays Scattering technique (SAXS) and Transmission Electron Microscopy (TEM) in order to achieve information on size, shape, polydispersity, agglomeration, and crystal structure (by SAED patterns) of the particles. Once characterised, the dispersions were tested in two different case studies, the Carceri dello Steri in Palermo with their graffiti and the 18th century lunettes at the SS. Giuda e Simone Cloister, Corniola (Empoli) with their lime-based mural paintings. The treated samples were characterised in relationship to either their morphology and surface chemical composition by Scanning Electron Microscopy coupled with Energy Dispersive X-rays spectroscopy (SEM-EDX), or their water absorption and mechanical properties (resistance to material abrasion). The results obtained showed that all the dispersions were nanometrically structured and their application succeeded in recovering the mechanical properties of the painting or graffito layers, not altering their permeability to water and keeping perfectly the wall transpiration. However, the dispersions constituted of the nanoparticles obtained via a synthesis able to control size and shape of the Ca(OH)2 particles resulted in a better performance in situ, even if the differences found by SAXS and TEM were slight.  相似文献   

8.
Almost everywhere public intervention in cultural heritage (CH) conservation is widespread. Using Italy as a case study, the paper analyses public capital expenditure for CH conservation and investigates whether the high degree of specialization of contracting authorities affects the efficiency of CH conservation works. A two-stage analysis is carried out. At a first stage, a nonparametric approach (Data Envelopment Analysis—DEA) investigates the relative efficiency scored by each single work; at a second stage, the determinant factors of the scores variability are investigated. The empirical analysis shows that, ceteris paribus, the expertise affects the efficiency of CH works.  相似文献   

9.
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   

10.
Many deterioration processes are linked to unsuitable microclimatic condition in cultural buildings. One of the most diffused processes is soluble salts crystallization that can be accelerated in masonry structures within specific microclimatic values for different chemical compounds. In this paper, microclimate and efflorescence diffusion were monitored over a one-year period in the Crypt of the Cathedral of Lecce (South Italy). This allowed to relate the microclimate with the efflorescence variation over time. A three-dimensional computational fluid dynamics (CFD) model was then developed to detail the thermo-hygrometric parameters and airflow patterns responsible for salts crystallization and artworks deterioration. Two main conditions were reproduced; one to simulate the current microclimate, which simulations showed to be inadequate for conservation, and the other to search for a more appropriate solution. In both cases, summer and winter conditions were simulated and compared to find a microclimate able to ensure more suitable thermo-hygrometric intervals required by the constituting artworks materials. The results helped to suggest actions to improve maintenance of the Crypt.  相似文献   

11.
  相似文献   

12.
The present work was one of the first attempts to analyze the conservation status of two ferrotypes, ancient photographic plates realized on a support made of iron. The photographic material was constituted of collodion as binder for the photosensitive silver halides grains. The two ferrotypes studied belonged to a private collection of a family from Durham, UK, and were made at the end of the 19th century. The analytical techniques used for the morphological and physicochemical characterization were noninvasive. The surface morphology was studied by means of optical microscopy (OM) and environmental scanning electron microscopy (ESEM) coupled with an energy dispersive X-rays (EDX) system for the elemental analysis. These techniques, together with microreflectance Fourier transform infrared spectroscopy (μ-FTIR) and contact angle, allowed to obtain information on both the chemical – elemental – composition of the materials constituting the ferrotypes, and the conservation status of these photographic plates. The study showed that the physicochemical diagnostics allowed to characterize the two ferrotypes that, despite their similar age and provenance, showed different conservation status, surface properties, and elemental composition.  相似文献   

13.
The critical condition of detaching historical murals in the Convent of Müstair (Switzerland) prompted a series of investigations and conservation actions over the last 40 years. After percussion tests in 1984/1992, an advanced technology of time-average TV-holography has been applied in 2000 and 2005. The primary aim was to substantiate if and to which extent detaching is in progress. This case study explores characteristics and limits of traditional percussion tests and time-average TV-holography. Extensive mappings by both techniques are carried out on two different structures of wall paintings. The comparison shows that the so-called percussion test – when combined with a close experienced observation – reveals a holistic picture of the general condition of a threatened painting. Time-average TV-holography, on the other hand, yields highly accurate relative information on the spatial distribution of detached areas. Therefore, it is apt to provide an exact answer to the question if detachment is in progress or not.  相似文献   

14.
The aim of this study is to develop a laboratory technique to simulate a natural ageing of canvas paintings adopting artificial ageing methods in air (thermal oxidation), in the absence of light. Four models of canvas paintings aged up to 315 years are considered. Paintings are constituted of oil film on oil ground layer, oil film on tempera ground layer, tempera film on tempera ground layer or by tempera film on oil ground layer. Surface strength and the colour of the paintings and the degree of polymerization (DP) of linen canvas were evaluated at different steps of ageing. The degradative result was estimated as the DP of linen canvas after prefixed times of microbial attack.  相似文献   

15.
The renaissance frescoes of the metropolitan cathedral of Valencia, located at the vault of the apse, were restored in 2006. We describe a microclimate monitoring system that was implemented for the preventive conservation of the paintings. It is comprised by a set of temperature and relative humidity sensors positioned at different points of the vault. This system is rather unique because some of these sensors were inserted inside the paintings during the restoration process. A principal components analysis was applied to the data of relative humidity recorded in February 2007. The analysis was repeated in three additional months of 2007. The resulting loading plots highlight the most relevant similarities and dissimilarities among sensors. These plots can be considered as some sort of control maps that could be used to detect abnormal conditions in the future. Actually, moisture problems at certain zones of the frescoes are causing the formation of efflorescence, and the sensors located close to these zones are the ones recording the highest values of relative humidity.  相似文献   

16.
The problem of environmental monitoring aimed at identifying and evaluating the weathering mechanisms affecting historical stoneworks is here discussed and a methodology based on the use of already available, long record, urban-scale environmental data is proposed. An example of its application to the Cathedral of Modena (Italy, XII-XIV century, included in the UNESCO's World Heritage List) is then presented. In this case, the methodology allowed the identification of the main degradation causes, which found significant confirmation by material diagnostics on the available samples and finite element structural modelling. Thanks to the decay causes identification allowed by the proposed methodology, more effective restoration procedures can be outlined.  相似文献   

17.
Holographic interferometry (HI) was chosen as the diagnostic tool to support non-destructive identification of structural defects commonly found in numerous art conservation problems. Holographic recording provides the highest information content of the concerned artwork and by implementation of a portable pulse laser the procedure becomes vibration isolation free for use outside the laboratory. Nowadays, it is comprehensively appreciated from art conservators that detailed structural knowledge is essential when conservation of precious artworks is concerned. The versatility of a holographic interferometer when used to acquire explicit structural information of art objects is demonstrated here in characteristic cases.  相似文献   

18.
A new possible methodology for recognizing the nature of gypsum in artworks, in particular for wall paintings, was developed. Calcium sulfate can be an alteration product of the calcium carbonate, or a component used by the Artist himself; the problem of identification of the presence and the nature of gypsum could be found detecting the presence of strontium. This element could be used as a marker since, differently from the alteration form, in mineral gypsum simultaneous presence of calcium and strontium occurs. The correlation between these two elements may be recognized using non-invasive in situ X-ray fluorescence measurements. In the present work, we tested this occurrence in various mineral samples of gypsum and alabaster as well in tempera, fresco and Egyptian paintings. Considering the new possible role of strontium indicating the presence of natural gypsum, we expect to provide a valuable tool for conservation scientists, restorers and art historians.  相似文献   

19.
During the past two decades, thanks to the rapid development of solid-state-based sensor technology, digital imaging emerged as one of the most attractive research areas for the noninvasive investigation of paintings and flat artworks. In particular, the commercial availability of high-performance digital cameras opened up new perspectives to transmitted imaging techniques, such as trans-illumination and trans-irradiation, which are based on the acquisition of the visible (Vis) and near infrared (NIR) radiation, respectively, transmitted through the object. Until recently, these techniques were indeed considered to be unsuitable for applications on artefacts, because of the risks of overheating and overexposure to the light of the object under analysis. Nowadays, with the new-generation digital cameras, transmitted imaging can be reconsidered as a possible tool for noninvasive diagnostics on paintings on canvas. These techniques have been proven to be effective for the examination of hidden details, such as underlying drawing, for a study of the pictorial style or the executive techniques, as well as for assessing the state of conservation of the supports. Both trans-illumination and trans-irradiation can be easily implemented by means of professional photographic digital cameras, and therefore offer a valuable alternative to the more expensive well-established methodologies, such as X-ray radiography. In some cases, they are found to be complementary to the conventional techniques in revealing details of the underlying paint layers. Potentials and limits of transmitted imaging techniques are discussed in this paper, starting from three case studies of oil-paintings on canvas that belong to the permanent collection of the Gallery of modern art at the Pitti Palace in Florence.  相似文献   

20.
Zinc oxide nanoparticles were prepared and used for surface treatment of oil paintings painted on paper supports. The prepared coating mixture containing 2% of ZnO nanoparticles showed excellent transparency. The effect of coating on protecting the paper support and paintings against microbial attack by Trichoderma reesei and Aspergillus niger, dirt accumulation, and UV aging was studied. Coatings containing ZnO nanoparticles enhanced the durability of linseed oil-based paintings toward UV aging regarding the change in color. Coatings containing ZnO nanoparticles improved resistance to microbial attack when subjected to inoculums containing T. reesei or A. niger fungi. In addition, coatings containing ZnO nanoparticles reduced accumulation of dirt on oil paintings when left in open air for 6 months; cleaning of paintings was quite easy compared to the non-coated paintings or those coated with the varnish without ZnO nanoparticles.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号