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1.
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2.
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   

3.
With the aim of identifying new water dispersed polymers for textile conservation, the structure and properties of three commercial polyacrylates and one commercial polyvinylacetate were analysed. The characteristics of these materials, not previously used in the conservation and restoration fields, were compared with that shown by Primal AC33 and Mowilith DMC2 and SDM5, widely used as consolidating or adhesive agents of ancient textiles. To achieve a thorough characterisation of each polymer, molecular, thermal, structural and mechanical investigation techniques were applied on film samples, obtained from polymer water dispersions through water casting at room temperature and/or compression moulding. The photo-oxidative resistance of these materials was also assessed by artificial weathering of water cast films and by measuring the Yellowing Index (YI) as a function of the exposure time under xenon-arc lamp. Collected data were used to appropriately compare the performances shown by these polymers when applied on artefacts consisting of natural fibres. In particular it was found that, among the products not previously used in the conservation and restoration fields, a high potential for carrying out treatments on textiles is shown by the samples commercialised with the trade names of Acrilem RP6005 and Acrilem 30WA. These products, in fact, exhibit properties that make them suitable as substitutes for Primal AC33 and Mowilith DMC2 and SDM5, respectively, depending upon conservation needs. It was very interesting to note that Acrilem 30WA, also after aging, shows YI values lower than that shown by Mowilith DMC2 and SDM5.  相似文献   

4.
This article illustrates a preventive conservation methodology for wooden collections and objects based on the respect of the historic climate, as established by the European standard EN 15757:2010. This requires the knowledge of the past indoor climate that should be kept unchanged in the present and the future, because discontinuities would be noxious for conservation. To this aim, a very vulnerable object, i.e. a wooden inlay bookcase cabinet built by G.M. Platina in 1477 AD has been considered. The paper illustrates the methodology used to reconstruct the historic climate, i.e. with proxy data from 1500 to 1715 and from 1716 to 2009 with instrumental observations. For the present, the indoor climate of the exhibition room and the cabinet response have been investigated to remove the perturbing factors that are damaging the cabinet. For the future, the ENSEMBLES model has been used for a probabilistic forecast of the temperature and humidity over the next century, the sustainability and the potential risk for conservation connected with the expected climate change. This research constitutes an example of a novel methodology based on the relevance of the Historic climate, and includes a synergistic effort of climatologists, material scientists and conservators, to be applied for preventive conservation and to evaluate and face the negative impact of the expected climate change.  相似文献   

5.
The preservation of early 20th century, late 19th century albumen prints is of great concern to collection managers and conservators of photographic materials. Attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR) spectroscopic imaging is presented for the first time as analytical methodology for the study of albumen photographs. This paper shows the feasibility of obtaining FTIR images of samples from albumen photographs with a high spatial resolution using a Ge ATR objective coupled with an infrared microscope. The improved spatial resolution compared to FTIR images obtained by the reflection method is due to the high refractive index of the ATR crystal, which gives a high numerical aperture and hence, a higher spatial resolution. The technique reveals detailed information on the organic functional group distribution in the individual layers of embedded cross sections and is used complementary to visual microscopy and scanning electron microscopy/energy dispersed X-ray spectroscopy. The main results of the study are discussed with regard to their historical and artistic significance, and they are compared with data from historical and conservation literature.  相似文献   

6.
In this study, the dyes present in five 17th- to 18th-century textiles from the National Museum of Art of Romania, three religious embroideries and two brocaded velvets, are characterized and discussed, together with earlier results on textiles from Romanian collections obtained by the same research group. Dye analyses were performed using two methods: the well-established liquid chromatography-diode array detection (LC–DAD) and a recently developed liquid chromatography-mass spectrometry (LC–MS) analytical protocol. The examination of very small historical samples by both techniques allows a better insight in the advantages and limitations of the two approaches to real analyses to be obtained. LC–MS data interpretation is based entirely on the results accumulated for dye standards. Electrospray ionization (ESI) was used in the negative ion mode and an ion trap served as mass analyzer. Both single stage (MS) and tandem (MS/MS) mass spectrometric approaches were considered. The dyes and natural sources identified by both analytical techniques are discussed in the historical context of the textiles, with respect to earlier results collected for similar Romanian objects. The study showed that the dye sources found in the 17th- and 18th-century Romanian velvets and embroideries were produced using a wide variety of dye sources, suggesting influences from Europe as well as from Asia Minor. Dye sources imported from New World have been also detected. The range of biological sources is in very good correspondence with earlier results obtained from textiles in the Romanian Collections. LC-MS (single stage and tandem MS) approaches have been demonstrated to be valuable tools for dye identification in small-scaled samples from historical textile objects only if sufficient knowledge on the dyes and their biological sources is first accumulated within experiments performed on standard dyes and standard dyed fibers.  相似文献   

7.
AimEstimating physical stability as well as revealing signs of fabrication in metal artefacts via two complementary nondestructive methods, neutron- and X-ray tomography were the main goals of this study.AbstractTo aid conservation management of metal artefacts improved knowledge of the internal structure and degree of corrosion therein is highly desired. In this study, neutron- and X-ray tomography were chosen as two complementary noninvasive visualization techniques to study internal structure and corrosion of five representative examples of archaeological metal artefacts from the Mapungubwe museum collection. Tomography was performed at the Neutron Radiography (SANRAD) facility of the South African Nuclear Energy Corporation where thermal neutrons as well as complementary X-rays are conveniently available under one roof. Comparative studies revealed neutron tomography to be generally superior to X-ray tomography due to the enhanced penetration properties of neutrons through the metal objects. In this paper the rich capability of neutron tomography as a nondestructive visualization aid for scientific conservation purposes is introduced and supported by results achieved for the five selected real artefacts.  相似文献   

8.
Metallographic features of ancient bronze artefacts often hide peculiar micro-chemical processes and corrosion behaviours, which are worth to be studied as they can provide conservators and archaeologists with valuable tools and information. It is widely documented that Chinese bronzes were cast and the way to adjust their properties was to change the alloy composition. In particular, addition of lead, which is insoluble in the bronze matrix, results in the formation of inclusions or globules, which undergo oxidation processes leading to their conversion into corrosion products. The mechanisms through which this occurs were still poorly investigated. The present work was conducted to further study the corrosion behaviour of high-leaded bronze, especially focusing on the behaviour of lead globules. To this aim, a collection of Chinese archaeological bronzes, showing intermediate steps of degradation, were selected and investigated. The use of combined microscopy-based, molecular and elemental, analytical techniques allowed the characterization as well as the precise location of corrosion products, thus enabling us to propose a degradation pathway basing on thermodynamic data provided by Pourbaix diagram. The achieved results will be useful for researchers involved in these kinds of studies to better interpret data obtained.  相似文献   

9.
This work describes the quantitative analysis of mercury present in the ink used to colour some books of XVIII century. The mercury content was determined by Energy Dispersive X-ray Spectrometry. This is a non-destructive technique which allows elemental identification and quantification (Z > 13) by atomic physics processes. The organic pigments cannot be identified by this technique, taking into account that its composition is mainly C, O and H. Levels of 2 wt.% and 4.5 wt.% were measured in 1756 and 1753 books respectively. No significant amount of mercury was observed in other red books, on a total of 11, all from XVIII century: 1720, 1732, 1753, 1756, 1780, 1798, 1800. More than one book for each year were analysed. The studied books belong to a private collection, and were selected taking into account the age and the reddish colour of their external parts. High content on Fe were observed in some of the books. This work highlights the application of a physics technique in a very important aspect for art and cultural heritage conservation and restoration, considering that high levels of toxic elements might be found in ancient documents. It is of great importance that preliminary elemental analyses are performed on ancient documents before handling them, because they might constitute some danger for restorers, conservators and collectors. This work highlights, for the first time, the danger of some ancient books. They might contain a very high concentration of mercury, which is toxic for the organism. This is also a particularly important problem of public health never mentioned in literature before.  相似文献   

10.
The paper presents strategies for the conservation of historical textiles in Egypt that have been in uncontrolled storage and display. The silk textile is highly decorated, multicoloured and dates to the Ottoman period, and was exhibited in case # 12014. The textile has various types of deterioration. An examination and analysis of the textile was undertaken in order to develop a plan of conservation treatment. FTIR was used to identify the kinds of dyes and organic stains, and XR-D was used to identify mordants and dust. Light microscope and SEM were used to identify the kind of fibers, their condition and surface morphology. The effects of cleaning materials on the natural dyes were tested. The researcher designed a new metallic frame support system which has advantages over the wooden frames commonly used in Egypt. This presentation will review the conservation treatment step by step. Poultices were used to remove all the sticking cardboard and adhesive. Old conservation repairs were removed. Separated parts were supported. Cleaning included mechanical and wet cleaning. New silk fabrics dyed with natural dyes were used to complete the missing parts. The textile was supported on new linen fabric which was stretched on a metal frame. The method of exhibition will be discussed. Photographs are included to document the conservation process.  相似文献   

11.
The Oxford University Scanning Proton Microprobe Unit has been responsible for many advances in the field of focused proton beams for analytical microscopy, including being the first to develop the optimized electro-magnetic lenses used to focus high-energy protons to the micron and sub-micron level. This has led to a revolution in using the proton microprobe as an analytical tool for the study of materials. Continuing the tradition of innovation at the Oxford SPM unit, the use of laser ablation to reduce the need for sampling or cleaning of art and archaeological objects, before analysis, is being investigated. Further, information on the makeup of corrosion layers and past conservation treatments is becoming available via this technique.  相似文献   

12.
Selected copper alloy artefacts from the collection of the Umm Qais museum at Irbid, Jordan, were studied by SEM-EDS analysis, while in situ analyses were performed by means of portable μ-XRF and LIBS spectrometers. Analysis and characterization of base metal and corrosion products of the copper alloyed artefacts were performed in relation to the environmental conditions of the display and as part of the overall assessment of the museum environment. Findings of this study are directed towards guiding a preventive conservation strategy for the copper alloyed artefacts at the Umm Qais museum.  相似文献   

13.
The seismic assessment of art objects requires a multidisciplinary approach and the definition of a specific methodology for evaluating the level of safety and the possible interventions necessary for seismic risk prevention, finding a compromise between safety and conservation. This paper describes a first step in this direction, in which the different aspects of the procedure, from knowledge path of the art object to the structural analysis, were studied in the six Michelangelo's statues located in the “Galleria dei Prigioni” (Slaves’ Gallery) at the Accademia Gallery of Florence. We showed that the general principles and criteria expressed in the “Italian Guidelines for evaluation and mitigation of seismic-risk to cultural heritage”, which are specifically devoted to masonry constructions, could be profitably extended to other artworks, like statues, starting from historical research, geometrical survey and material characterization, up to the developing of specific methods of analysis. This research could be the base for future studies to be performed concerning the prevention of seismic damage of art objects, including both bare minimum interventions and specific devices, such as isolation systems.  相似文献   

14.
There is little information in the conservation literature with respect to artists’ alkyd paints; thus, artists and conservators are somewhat at a loss about how to use and treat alkyds. Recently, analytical methods have been developed to identify the components in these polymers (oil modified polyesters), rates of cross-linking and mechanical properties. Presented in this paper are some of the characterization results of artists’ alkyd paints using THM (thermally assisted hydrolysis and methylation) gas chromatography– mass spectrometry (THM–GC/MS) and Fourier transform infrared spectroscopy–attenuated total reflectance (FTIR–ATR). Four brands of artists’ alkyd paints containing alkyd resin have been analysed; one containing a phthalic anhydride and pentaerythritol based alkyd resin, two containing isophthalic acid and pentaerythritol based alkyd resins, and the final one containing both phthalic anhydride and isophthalic acid and pentaerythritol based resins among the colours studied.  相似文献   

15.
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   

16.
At the instigation of the Musée du Louvre's Department of Egyptian Antiquities, an intensive programme to study black bronze has been carried out at the Centre de Recherche et de Restauration des Musées de France. Systematic research has been undertaken on the museum's collection to identify objects that might have an intentional black patina.The same experimental protocol has been applied to all the objects, alllowing this study to be one of the most important coherent investigation on this type of bronze decoration. It involves the use of non-invasive analytical methods in order to obtain the maximum amount of information possible about the chemical nature and structure of the surface layer. The protocol makes it possible to compare objects and to propose an interpretation of how this decorative technique evolved during the Egyptian period.Based on previous stylistic investigations (by J. Cooney, 1966) and personal observation, sixteen objects dating from the Middle Kingdom to the Late Period were selected. Thanks to elemental analyses, twelve of them were identified as being intentionally patinated. Only ten of these could be described as hmty-km, because the base patinated alloy contains small amounts of gold and/or silver and the black patina is made up mainly of cuprous oxide Cu2O (cuprite). Among the four other objects, one patina is very close to the black bronze patina, but contains neither gold nor silver. Three other pieces have an unusual patina. A lack of other comparable examples makes it very difficult to determine whether the patinas are of ancient origin.  相似文献   

17.
This paper presents the results of a light levels survey conducted at the Donald W. Reynolds Center for American Art and Portraiture in Washington DC. The museum space is shared by the National Portrait Gallery and the Smithsonian American Art Museum. After six years of extensive renovations, the building reopened to the public in July 1, 2006. The structure was not originally designed to house a museum collection since it contains numerous openings such as windows, doors and skylights, which provide a path for natural radiation to enter the building and come in contact with the artworks. From a preventive conservation standpoint, this is an important problem since sensitive works of art in the collection may be subjected to damage caused by light exposure. Environmental data loggers installed throughout the museum were programmed to take successive measurements every 10 min for 24 h a day, 7 days a week and 52 weeks a year. This light levels assessment started in November 1, 2007 and finished in October 31, 2008. This study presents a new method for determining natural radiation exposures registered in exhibition spaces that rely on both electric lighting and natural lighting, considering the growing trend of using daylight illumination in museums.  相似文献   

18.
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   

19.
Red lake pigments and dyes used in works of art were characterized by microspectrofluorimetry, a new tool in the field of cultural heritage. Emission and excitation spectra were obtained with high spatial resolution (8–30 μm) in cross-sections from paintings by Vincent van Gogh and Lucien Pissarro and from millenary Andean textiles. The fluorophores were identified by comparing their spectra with those from historic reconstructions assembled in a database. In the paints, purpurin and eosin lakes were detected. In the Paracas and Nasca textiles, dated from 200 B.C. to A.D.1476, purpurin and pseudopurpurin were the red dyes used. Carminic acid was detected in textiles dated close to the Inca Empire, A.D. 1000–1476. The results obtained with this new technique were confirmed and are in agreement with those obtained with conventional methods, requiring microsampling, such as HPLC-DAD-MS and SEM-EDX.  相似文献   

20.
Based on both a historic and documentary and a physicochemical approach, the study is attempting to codify well-adapted antique, medieval and traditional textile dyeing recipes; to reconstruct them through a detailed sequence of simple and reproducible operations; and to optimize the methodology at all stages, i.e. extraction of the colouring principles, as well as mordanting and dyeing; the latter being evaluated through standard light and wash fastness assessments, and on the basis of systematically obtained colorimetric data. As colouring agents are considered saffron, turmeric, weld, Persian berries, henna, safflower, dyer's bugloss, madder, scale insects, sappan and Brazil wood. A variety of mordants, namely FeCl3, SnCl2, K2Cr2O7, ZnCl2, CuSO4, and KAl(SO4)2·12H2O, is anticipated to meet both early and rather recent options, while being easily available. Based on a large collection of ancient proposals and optimized by means of methodical assessments, the standardized dyeing processes proposed are simple, reproducible, and perfectly reliable for use in the preservation of the relevant tangible heritage, and the revival of traditional arts and crafts; and are consequently beneficial to artistic weavers, as well as conservators and restorers of textile products.  相似文献   

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