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1.
Laser cleaning has been used to restore the soiled terracotta statues and decorations of the tympanum of the portal of Palos of the Cathedral of Seville in Spain. A simultaneous laboratory study performed on a representative sample helped to identify the optimum laser conditions to remove the dark soiling layer produced by air pollution. It was found that irradiation at 1064 nm with a Q-switched Nd:YAG laser was more effective than the harmonic wavelengths of 532 or 266 nm. LIBS and Raman microscopy gave information on the composition of terracotta and identified the presence of a protective layer made of gypsum and calcite. As detected by Raman spectroscopy, laser irradiation caused the elimination of the carbon component of the soiling layer and the appearance of an anhydrite component in the laser irradiated gypsum layer applied over the terracotta substrate for protective purposes. Local heating of the surface caused by laser irradiation at 1064 nm, the laser wavelength used for restoration of the portal, might be responsible for a process of partial dehydration of gypsum into anhydrite.  相似文献   

2.
The oil painting “La Medusa” executed by Caravaggio at the end of the XVI century on a wooden shield, was investigated by integrated physical–chemical and analytical methodologies in order to obtain scientific data capable of elucidating the state of conservation and the painting technique. Optical (OM) and electronic (SEM-EDS) microscopy, micro-FT-IR spectroscopy, gas chromatography–mass spectrometry (GC–MS) and pyrolysis GC–MS were applied on two microfragments and some organic samples obtained by solvent extraction using the swab cleaning technique. The obtained results indicated that Caravaggio probably reused an old shield as a previous gypsum preparation layer has been detected under the original painting layers. He used white lead, natural earths, verdigris and lead–tin yellow type I mixed with drying oils to paint. The considerable amount of amorphous particles of copper chlorides found in the green pigment verdigris suggests that it could have been produced according to the ancient recipe of verde salsum described by Theophilus. Mordant gilding has been identified on the upper part of the shield that can be related to an abandoned experiment to give the painting a mirror-like reflecting effect. Three different varnishes layers have been detected above the painted surface. The original and restoration varnishes have been identified and they contain a mixture of drying oil, mastic and turpentine and some beeswax. Cleaning tests, performed with different organic solvents, suggest the use of isopropyl alcohol as cleaning agent because it is less efficient in comparison to others solvents; thus it ensures a careful and controlled removal of the varnishes.  相似文献   

3.
Due to the extreme fragility of paper-based artefacts, few techniques are available for scientific investigation and characterisation of ancient drawings or paper-based artefacts. Image reflectance spectroscopy represents an almost unique tool for scientific analysis on precious drawings, for which even micro-invasive techniques of analysis cannot be used. Indeed, beside the high fragility of the support, drawings and graphical works are typically characterised by a very limited number of artistic materials, which in principle could give information on the work of art. In this paper an interdisciplinary study on a set of drawings by Parmigianino (1503–1540), selected from the collection of the Uffizi Gallery in Florence, is presented. Non-invasive measurements of image spectroscopy (IS) have been employed to support the work of art-historians in the critical re-examination and interpretation of the graphical work of the artist. The multispectral analysis has been carried out over the extended spectral region (400–1700 nm), in order to provide simultaneous indications both on the pictorial materials and on possibly underlying hatches. The data processing has been performed by means of Principal Component Analysis (PCA) and the elaboration of each case has been addressed to specifically respond to questions related to the art-historical problem.  相似文献   

4.
The sarcophagus containing the remains of Federico II, located in the Cathedral of Palermo (Sicily, Italy), was opened on 1998 to perform a multidisciplinary survey [1]. Next to the remains of Federico II and in close contact with them were laying two other skeletons belonging, according to historical records, to Pietro II di Aragona and to an anonymous person (“The Third Individual”), probably a woman. The bones appeared severely deteriorated. Chemical analysis performed on bone samples excluded that the bodies underwent some kind of embalming process. The analysis of mtDNA from bone samples taken from the three skeletons was successful in only one of the two labs involved. The HVR1-mtDNA sequence (region: from nt 16,035 to nt 16,395), obtained from the bone samples of Federico II and “The Third Individual” appear identical but bear double peaks at the same nucleotide positions, suggesting mixing (i.e. contamination) of different mtDNA types. The HVR1 sequence obtained from the bone sample of Pietro II di Aragona does not present double peaks and differ from the Cambridge Reference Sequence (CRS) at six nucleotide positions. Cloning experiment of the Federico II amplicon demonstrated that the mixed mtDNA types are only two: one identical to CRS, the other identical to the sequence of Pietro II di Aragona. A reconstruction of these data are proposed in the Discussion. Due to the problematic context in which this study was carried out (mixed and deteriorated biological material, failure to replicate results in two different labs), our results and reconstruction can only be offered on a tentative basis. It is hoped that the data presented in this study will reveal useful, for future comparison, if further molecular genetics research will be carried out on the royal dynasties that ruled Sicily in the early centuries of the past millennium.  相似文献   

5.
This work presents an account of the results of diagnostic analyses on the lesions that were first detected in Michelangelo's David in the mid-1800s. After summarizing the events that may have affected the statue's stability and the state of deformation, the authors present the results of the Finite Elements Method (FEM) tests conducted on the digital model of the statue's surface. The analysis of these results made it possible to identify the static conditions that generated the cracks in the lower part of the left leg and in the tree trunk of the David. Lastly, the current situation was analyzed from the perspective of both deformation and stresses, evaluating the statue's stability also as regards its structural response to the seismic activity at the level expected for the Florence area.  相似文献   

6.
As part of research in progress on the study and design of an ontology knowledge model, this paper focuses on development of a shape-grammar schema for extracting attributes of spatial organization of a subset of cultural heritage relics, namely, caravanserais, from a selected corpus with a common architectural language of design. First, shape-grammar rules for classification of caravanserais of the selected corpus are developed and are represented in drawing by using Auto CAD tool. Shape rules as a natural-language equivalent are then devised by describing design functions and clarifying the topology of shapes. Based on these shape rules in given text, the hierarchy of a shape-grammar schema in the Protégé knowledge representation tool is designed, and each shape rule is defined as an interconnecting individual (or instance) in OWL language. This schema will enable us to extract computer-based semantics of shape-grammar rules. To illustrate this innovative approach, a selected corpus was classified by using the shape-grammar schema with the support of knowledge extraction tools.  相似文献   

7.
The application of total reflection X-ray fluorescence (TXRF) to the analysis of inorganic pigments used in five Albanian icons painted by Onufri Qiprioti, in the period from the end of 16th to the beginning of 17th century is presented. After removing the protective varnish with a solvent, a dry cotton-wool bud (Q-tip) was rubbed over the painted surface to collect the micro-samples. Samples, covering the main colors and their hues, were collected of each icon. A part of the small amount of the sample was transferred to a glass carrier and analyzed by TXRF. Main types of inorganic pigments used for different colors could be identified. The results indicate a palette which included white lead, calcium white, gold, orpiment, yellow and red ochre, vermilion, red lead; a cooper based green pigment (malachite or verdigris) and smalt.  相似文献   

8.
Fifty crucible fragments and 10 fragments of the melting furnace of the forest glassworks of Südel (1723–1741, Ct. Luzern), were analyzed by petrographic, mineralogical and chemical techniques in order to assess the temperature reached in the melting chamber and to find out which raw materials were used to make the crucibles and the melting furnace. Since the crucibles were used in the melting furnace, the temperature estimations were based on both the crucibles and the refractory fragments, as they were parts of the same system. The temperature range in the melting chamber, estimated by the structural order of the new-formed cristobalite, points to a temperature range between 1350 and 1500 °C. However, three crucible samples recorded extreme temperatures as high as 1650 °C, suggesting very high flame temperatures for wood fuel. The analyzed red bricks were made with local calcium-poor clay. One of them was tempered with refractory fragments, demonstrating an in-house production and the recycling of such a material after its use. The crucibles and the refractory bricks were made with the same refractory clay. The former using unprocessed clay and the latter blending clay with chamotte. A comparison with Sidérolithique clayey sand samples from the Swiss Jura, shows strong affinities which may rule out the archaeological hypothesis of an exclusive provenance of such clays from Germany, suggesting an import from the Swiss Jura mountains.  相似文献   

9.
The efficiency of a recently described non-aqueous method for paper deacidification using Ca(OH)2 nanoparticles in isopropanol was evaluated by pH and colorimetric measurements and by the analysis of the degree of polymerization (DP). Samples of plain paper and paper with iron gall ink were tested. The results were compared with non treated samples and samples submitted to the traditional treatment with saturated aqueous Ca(OH)2 solution. By comparing the two conservation methods, the aqueous one shows higher neutralization reaction kinetics than the non-aqueous one. The iron gall ink samples maintain their coloration closer to the original after the non-aqueous Ca(OH)2 nanoparticles treatment, in contrary to the aqueous treatment that changes the ink aesthetics considerably. Artificial aging tests revealed a general increase in the aging stability of deacidified paper samples. The Ca(OH)2 nanoparticles treatment can be an alternative for papers who can not be treated by the classical aqueous treatment, e.g. papers with water soluble components.  相似文献   

10.
The analysis of the amino acid (AA) content in fragments derived from a prehistoric rock pictograph (Lancusi rock shelter) at Tadrart Acacus, southern west Libya, revealed the presence of material containing peptides differing in solubility in hot acidic or alkaline solutions, as well as in AA composition and racemization. Water-soluble components were constituted of low molecular weight peptides with high racemization of aspartic acid and alanine, whereas the water insoluble material consisted of species of a more complex AA composition and a different degree of racemization. The proteinaceous materials were assumed to originate from matter that had undergone over time different diagenetic processes. The water insoluble peptide-containing material was separated from the rock substrate by acid hydrolysis, dried and the resulting residue submitted to radiocarbon analysis. Accelerator mass spectrometry (AMS) yielded an approximate age of 6145 ± 70 years B.P. (before present), which is consistent with archaeological inference and the climatic reconstruction of central Sahara. To our knowledge the present work represents the first attempt of direct radiocarbon dating of rock art in the Sahara desert.  相似文献   

11.
As an important element in the cultural heritage of a people, traditional rural constructions need to be conserved over time. Graphic and metric documentation methods play a key role in the preservation of cultural heritage. In this paper different existing methods of graphic and metric documentation are analysed in order to select the most suitable for the documentation of agro-industrial buildings according to their characteristics. The selected one is a simple close-range photogrammetry method, which is affordable and easy to understand for non experts. It is based on the use of plumb lines, a conventional digital camera and monoscopic restitution. The application of the method is illustrated in a particular case consisting on the graphic and metric documentation of a windmill. Also the accuracy of the method is evaluated in this particular case.  相似文献   

12.
In order to protect historical buildings in the northwest China from fire, the most of which are temples for Buddhism, water mist suppression system is chosen due to less damage on water-soluble decorations. This study is to investigate the feasibility and efficiency of water mist suppressing fire occurred in historical buildings. Eternal ghee lamp over the years is serious fire hazard for these temples. In this paper, the interaction of water mist and ghee flame under different external radiant heat fluxes is studied. Water mist was generated by a downward-directed single pressure nozzle. The heat release rate, carbon dioxide and carbon monoxide concentrations, and other important parameters of the interaction under various experimental conditions were measured with cone calorimeter. It is indicated that water mist can assuredly suppress ghee flame. But ghee combustion is enhanced for a short time just on discharging water mist, and then ghee flame is extinguished quickly under continuous water mist application.  相似文献   

13.
The stained glass windows of the Pavia Carthusian Monastery are an important testimony of medieval glass making in which a wood-ash flushing component was used. Glass surfaces reveal alteration processes extending to depth, with evidence of microbial corrosion. Electron microprobe analyses coupled with EDS data allow the identification of different steps in the alteration process. Microbial attack occurs in an early stage and determines component leaching of the glass, with the development of reactions in which the crystallisation of gypsum is favoured.  相似文献   

14.
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   

15.
Using inductively coupled plasma–atomic emission spectrometry (ICP-AES), atomic absorption spectrometry (AAS) and instrumental neutron activation analysis (INAA) the concentration of Ag, As, Au, Bi, Cu, Fe, Ga, In, Ni, Sb, Sn, and Zn in 53 samples taken from archaeological finds dated to 4th–2nd century BC and found in the territory of ancient Thracia was determined. Additionally using inductively coupled plasma–mass spectrometry (ICP-MS) and MS for determination of the lead isotope ratios in the samples was carried out. On the basis of these analytical results using cluster analysis for grouping the samples on the bases of the similarity in chemical and isotopic content and the available data from the literature for lead ore deposits in the Balkan Peninsula, the geological origin of the investigated archaeological finds was evaluated. That confirms the expectation that sources of lead might be almost all possible deposits of lead ores on the Balkan Peninsula—from Lavrion through Chalkidiki to the Rhodope mountain. The result indicates that the Thrace did not utilize one single lead source continuously but that lead was provided according to availability from different production centers.  相似文献   

16.
Optical and SEM-EDS microscopy, X-ray powder diffraction and micro FT-IR spectroscopy investigations of the funerary klinai (couches) of Tomb 1 from Amphipolis and a stone sarcophagus from ancient Tragilos—two painted monuments made by Macedonian craftsmen of the Early Hellenistic period—identified the original materials and painting technique, as well as synthetic materials used as consolidants during past restoration treatments. The original organic binders and the superficial modern coatings have been identified by micro FT-IR spectroscopy applied directly to the sampled powders or tiny fragments and to their solvent—soluble fractions. The pigments identified on the couch of Amphipolis are: red and yellow ochre, cinnabar, Madder lake, paratacamite and antlerite, carbon black, calcium carbonate, kaolin and gypsum. The identification of egg and animal glue confirms the application of tempera and secco techniques. The detection of polymers such as polydimethylsiloxane, polyvinyl acetate and alkyd resins, is related to modern restoration products. The pigments attested on the paintings of the Tragilos' sarcophagus are: red and yellow ochre, Egyptian blue, malachite, carbon black, calcium carbonate and gypsum. The absence of organic binders combined with the constant presence of calcium carbonate in all the examined samples suggests the use of lime as the binding medium in the painted decoration of the sarcophagus. The presence of Paraloid B72 is related to recent conservation treatments.  相似文献   

17.
琴、棋、书、画”是中国古代的四大艺术,而围棋则是各种棋类的鼻祖,相传已有几千年历史。战国时期就有“尧造围棋,朱丹善之”的记载。 吴清源是20世纪的围棋天才,被围棋界尊为“围棋之神”。  相似文献   

18.
This study reports the acoustic history of the Benevento Roman theatre, from its origins in the Roman period to today. The theatre, built in the second century A.D., was abandoned following historical affairs – e.g. barbaric invasions – and natural events (earthquakes, floods, etc.). The building materials were used during the Langobardic Age for the construction of defensive walls and for the adornment of churches and buildings. During the following centuries some houses were built in the theatre. At the beginning of the 1900s, the dominating houses were demolished in order to bring to the light the buried parts of the theatre and to consolidate the structures. The recovery work ended only in 1950. The theatre is nowadays not only an ancient monument, but also the centre of important social activities with national and international festivals of music, dancing and drama. Using a software for architectural acoustic, and with a 3D theatre virtual model, we predicted the acoustic properties during the Imperial Age. With acoustic measurements carried out in situ, we evaluated the acoustic properties in the current state.  相似文献   

19.
The paper deals with financing the culture in Italy. The public expenses for the culture are shared as expenses of the government, of the regions, of the provinces and of the municipalities. The relationships of the cultural organisations with the public sector are very strong because they belong to the public sector, or they broadly depend on public funds.A specific attention is devoted to other forms of financing, about the role of the entrance fees and the entrances of the game “Lotto”, which subsidy the cultural goods and the Interministerial Committee for the Economic Planning (CIPE) allocations to the depressed areas. We will also be faced up to the examination of other sources of private financing as the sponsorships, the entrances of collateral services about museum visits (coffee and bookstore) and the supply of banking foundations. The fiscal incentives refer directly to the cultural institution or to the external financing of the nonprofit institutions by donations or sponsorships. Finally, the cultural institutions will have always to operate more and more by a strategic vision of financial and managerial field, on the basis of high qualitative standards. The activities and cultural projects will have to be able to attract additional sources of income in addition to the public one; the search of private financial resources is developed in a situation of increasing competition among the institutions, while tools of innovative finance have to be used to satisfy the increasing demand of culture. It is difficult nevertheless to define the possible best method of public–private financing, if you take consideration of the distinctive features of the different institutions and interests of the operators who are involved: artists, cultural institutions, public bureaucracy, besides the economic effects which follow alternative choices. The recent evolution of the institutional, financial and managerial models of the culture in Italy plans a larger integration between public and private sectors for a great involvement of individuals, enterprises and foundations about the financing of the cultural services offer.  相似文献   

20.
Knowledge of the structural behaviour of existing masonry requires a multi-level approach, with the proper application of diagnostic and assessment methodologies. The structural performance of masonry wall structures can be understood provided that the history of their construction, their geometry, the characteristics of their masonry texture, and the characteristics of the masonry as a composite material are known. In order to obtain all these data, an effective on-site testing program, which can involve the application of different test methodologies as a combination of destructive tests (DT), minor destructive tests (MDT) and non-destructive tests (NDT), needs to be performed. Furthermore, the effectiveness of applied methodologies for the assessment of historical masonry structures strongly depends on the type of investigated structure, as well as on the appropriate numerical model for the analysis. However, the unclear aspects of any testing programme remain the same – how efficient is a particular testing technique, and how can it be assessed? Following the results of recently carried out EU and national research projects, a comprehensive set of data regarding the effectiveness of different testing methods, depending on the type of problem, have been collected and analyzed. Within this framework, several masonry heritage structures from Slovenia, which differ both from the historical and structural point of view (Pi?ece Castle, the Carthusian Monastery at ?i?e, and a typical stone-masonry house from the So?a Valley region), have been investigated by means of different techniques, and numerically analyzed. For this purpose, two different models were used: a push-over model based, on the structural element method, and FEM analysis. It was concluded that the effectiveness of any particular diagnostic technique for the investigation of masonry structures, and for the planning of their restoration, depends on numerous factors. An attempt to determine which of the techniques could be appropriate, depending on the problem, was made. No single test is self-sufficient for the solving of a particular problem, so a combination of different NDT, MDT and DT should be performed. Summarizing all the results, it can be said that, in the process of assessing the state of a structure, even a simple investigation technique is better than none. The effort will always be repaid - if not already in the planning stage of the restoration and retrofitting actions, then certainly in the execution stage of the revitalization works, on site.  相似文献   

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