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1.
《文物保护研究》2013,58(3):116-121
AbstractThough infrared spectroscopy is the single most powerful technique for the characterization of materials and though it is widely used in the chemical industries, its application to conservation has been severely limited due to the complexity and limited sample size of the materials presented for examination. In the past decade, the development of infrared Fourier transform spectroscopy has made possible the study of small samples and complex mixtures. The technique of infrared Fourier transform spectroscopy is compared to conventional infrared spectroscopy with reference to spectra of paper, egg yolk, albumin, madder, Indian yellow, purpurin, alizarin, indigo, and linseed oil. 相似文献
2.
Discoloured 18-carat gold decorations from Sweden have been analysed by scanning electron microscopy with energy dispersive X-ray spectroscopy and X-ray electron spectroscopy (XPS)/electron spectroscopy for chemical analysis (electron spectroscopy).The original gold composition was close to 75% gold, 13% silver, and 12% copper. After manufacture, many details were boiled in sulphuric acid. As a consequence of this, the surfaces are irregular and porous with a gold concentration around 90% and with less than 1% copper. With XPS the outermost 10–20 atomic layers could be examined. No copper was present here, and the silver concentration was significantly higher. Also carbon, sulphur, oxygen, and (in one case) chlorine were present. The valence numbers indicated that gold only occurred in its metallic state, while silver (as Ag+) was preferably associated with sulphur to form black silver sulphide (Ag2S). The grey discolorations are basically due to silver sulphide and organic dirt. Sometimes green, violet, and ‘copper-shining’ colours occur, presumably as a result of light refraction phenomena. 相似文献
3.
《文物保护研究》2013,58(3):204-215
AbstractThree paintings from a group of thirty-two attributed to Jackson Pollock (1912–1956) were examined at the Harvard Art Museums. Paint samples were examined using Raman spectroscopy, scanning electron microscopy–energy dispersive X-ray spectrometry (SEM-EDX), laser desorption ionization time-of-flight mass spectroscopy (LDI-MS), Fourier transform infrared spectroscopy (FTIR), pyrolysis–gas chromatography–mass spectrometry (py-GCMS) and carbon-14 (C-14) dating. Carbon-14 dating detected no 'bomb' carbon from atmospheric atomic testing. All three paintings contained pigments and media available only after Pollock's death, including PR 254, PY151, and an emulsion copolymer of n-butyl methacrylate and iso-butyl methacrylate. 相似文献
4.
《文物保护研究》2013,58(4):231-254
AbstractAnalyses of pigments from palettes used by J.M.W. Turner (active c.1792–c.1850) by means of microscopy, microchemical analysis, thin-layer chromatography, energy-dispersive X-ray analysis, X-ray diffraction and Fourier transform infrared spectroscopy are given. The occurrence of pigments in Turner's dated oil paintings and watercolours is also given, arranged by five-year periods. These findings are discussed in the context of published analyses of pigments from the first half of the nineteenth century. Turner used cobalt blue, emerald green, viridian, orange vermilion, barium chromate, chrome yellow, chrome orange and chrome scarlet within a few years of their known dates of discovery. It has become clear that Turner was using, or at least experimenting with, practically all the pigments known to be available at that time. In a few cases, in the light of these results, ideas on the availability of pigments to English artists have been revised backwards to the first known date of manufacture. Turner also possessed and used a wide range of red and yellow organic pigments, but few organic greens. The dyestuff extracted from Rubia tinctorum L. madder on an aluminiumcontaining substrate can be distinguished from the same madder on different substrates by its strong pink fluorescence in both ultraviolet and green light. The other red organic pigments (a second madder, brasilwood and cochineal dyestuffs on a range of substrates containing aluminium, copper, iron, aluminium/copper and clays) show negligible fluorescence. The red organic pigments were used in oil medium as well as watercolour, the yellows only in watercolour medium. 相似文献
5.
ABSTRACTAiming at contributing to the preservation of black and white (B&W) film-based negatives held by Portuguese archives, four photographic collections from the first half of the twentieth century were selected for study. During the macro assessment of the collections the preservation condition and hues found in photographic negatives from the Elmano Cunha e Costa (ECC) were noticed, distinguishing this collection from the remaining ones. Additional attention was given considering that the ECC collection was formed in a colonial context in the 1930s, while the others were formed on the Portugal mainland. The ECC collection results from an ethnographic survey of Angolan tribes recorded with B&W film-based negatives. In this collection, sets of negatives with pink, lemon yellow, greenish, orange brownish, and red brownish hues were found. To identify the origin of such hues, the image layer was analysed by microscale energy-dispersive X-ray fluorescence (μ EDXRF) and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX). Additionally, to assess the base decay and its effect on the formation of hues, the plastic supports were characterized by Fourier transform infrared microscopy (μ FTIR). To complement the assessment of the film-base decay, pH was measured by using combined microelectrodes. The identification of mercury, iodine, chromium, and iron by μ EDXRF allowed correlation of the hues found in the negatives with chemical corrective treatments performed to improve the image quality. SEM-EDX confirmed those results and proved that the elements found were in the photographic emulsion layer. The results obtained are relevant since the hues identified may now be used as markers to indicate the technical work performed on colonial photography. Additionally, the visual and molecular assessment of the negatives’ supports (good to fair condition) allow proposing that the original storage conditions may have had a beneficial contribution to their present condition. 相似文献
6.
Claudia Pelosi Davide Fodaro Livia Sforzini Claudio Falcucci Pietro Baraldi 《文物保护研究》2017,62(5):266-282
This work presents the results of the investigation carried out on a group of terracotta sculptures (modelli) (sixteenth to eighteenth century) belonging to the extraordinary collection of Palazzo Venezia in Rome. The study, the diagnostic analysis, and the conservation work, were possible thanks to the grant supplied by the Getty Foundation of Los Angeles and by the bank Intesa San Paolo. The terracotta modelli had a practical function as they were of great use as sketches to the creation of the final masterpieces or as models for restoration. As a consequence, the terracotta models allow reconstructing the creative process of artists and restorers, fundamental to outlining the ancient workshop production. X-ray fluorescence spectroscopy, micro-stratigraphic investigation, Fourier transform infrared spectroscopy, and micro-Raman spectroscopy were chosen as useful techniques to study the morphology and composition of the surface-painted layers. Usually the surfaces were painted in order to simulate the materials of the sculpture for which the model was created, for example lead white was used to obtain a white surface simulating marble. But, often the models were re-painted to make them more attractive for the antique trade. So, several pigments have been found on the surfaces such as zinc white, Prussian blue, chrome yellow, and mono-azo pigment. In some cases, the characterization of the surface paintings was particularly important to the final decision about removing or leaving the surface paint in place. 相似文献
7.
《文物保护研究》2013,58(3):165-184
AbstractThis study investigates the effects of a selection of alkaline reagents, including solutions, pastes and soap gels, used to remove an artificially aged mastic film applied over a primed canvas. Surface changes were examined using visible light and scanning electron microscopy (SEM). Ammonia, whether in solution or gelled with hydroxypropylmethylcellulose (HPMC), required a pH of 10 or higher to remove varnish at an appreciable rate, whereas ammonia in wax paste worked at pH 9. Soap gels based on deoxycholic acid (DCA) were effective at pH 9·5. The rate of removal increases significantly with the addition of benzyl alcohol, while anthracene-9-carboxylic acid (A9C) and 9-fluorenone-4-carboxylic acid (9FOC) soap gels of pH 7·9 worked quickly without the addition of alcohol. Where reagents with a pH of more than 9 were used, some erosion of the priming was observed under SEM. Examination of the topography of residual varnish after treatment and Fourier transform infrared spectroscopy (FTIR) measurements provided evidence in support of models for the mode of action of reagents and soap gels on aged varnish. Ammonia, whether in solution, gel or paste, removes varnish by fracturing on a multi-molecular scale; soap gels not -specifically tailored to remove the varnish act similarly. A9C and 9FOC gels remove the varnish by thinning from the upper surface without fracturing. 相似文献
8.
The Powerhouse Museum in Sydney, Australia houses the world's most significant and comprehensive collection of Speedo swimwear and accessories. The museum has identified a problem with the long-term storage of certain Spandex/Lycra® items where the elastane fibre has degraded leading to oil formation. Attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) determined that most of these garments were manufactured using nylon-elastane fibres, and the elastane component comprises polyetherurethane or polyesterurethane polymers. Certain polyesterurethanes are known to be vulnerable to hydrolysis, and this was confirmed for a subset of the collection using two chemical testing protocols, and a thermal testing protocol that reproduced the oil formation. A polyetherurethane garment in the collection was unchanged by these tests. The oil from the thermal testing was confirmed as a breakdown product of the polyester component of the elastane fibre, using ATR-FTIR spectroscopy, X-ray photoelectron spectroscopy, and time-of-flight secondary ion mass spectrometry. The study demonstrates the value of ATR-FTIR for minimally invasive identification of elastane fabrics that may require specialized storage in a humidity-controlled environment. 相似文献
9.
Birgit Schwahn 《文物保护研究》2014,59(3):161-179
Two sixteenth-century Limoges painted enamel plaques by Léonard Limosin in the collection of the J. Paul Getty Museum, Los Angeles, show a remarkable restoration technique consisting of separately enameled pieces that have been inserted into areas where original enamel was lost. A detailed investigation of the two plaques brought information about this former restoration method and the materials used. Investigation included optical microscopy, UV-A examination, and X-radiography for identification and mapping of the insert restorations, scanning electron microscopy with energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and gas chromatography-mass spectroscopy for analyzing organic restoration material as well as X-ray fluorescence for studying the enamel compositions. A survey of six other Limoges painted enamel collections in the USA was carried out, which revealed many more of these insert restorations and indicated particular damages related to the so-called paillon designs on silver or gold foils. A literature review was undertaken focusing on possible causes of the damage as well as on persons and workshops that may have executed the insert restorations. 相似文献
10.
11.
《文物保护研究》2013,58(1):10-16
AbstractFourteen tesserae from the mosaics in the Cathedral of Salerno were examined by X-ray diffraction and by energy-dispersive X-ray analyses. Their constituents were identified and they can be divided into crystalline and amorphous materials. The main crystalline phases are quartz, calcite, magnesium carbonate, magnesium hydroxide and microcline. The amorphous materials are composed of silica containing several elements: Ca, Na, K, A1, Fe, Cr, Mn, Ni, Ti, Cu. For comparison, one tessera from Pompei was characterized. A subdivision of tesserae into three groups, crystalline, amorphous and composite, is suggested. 相似文献
12.
A green waxy paint was found on some fragments of jars at the Metropolitan Museum of Art made of Egyptian alabaster and dated to the Nineteenth Dynasty (1292–1182 BC). Four different types of particles were seen in these paints: green, blue, red-brown, and semi-transparent. The blue particles were identified as Egyptian blue. The green particles present problems as it is still not certain whether they are an original green or an altered blue particle. X-ray fluorescence revealed that copper is the main element in the green waxy paint. Fourier transform infrared spectroscopy (FTIR) found that an extra peak formed at 1588 cm?1 which correlates to organo-copper salts. Gas chromatography-mass spectrometry analysis confirmed that the binding medium of the waxy paint is aged beeswax. Laboratory experiments showed that heating beeswax with malachite, chrysocolla, verdigris, and copper acetate, as well as heating beeswax in a copper crucible, generate the diagnostic 1587–1588 cm?1 peak in the FTIR spectrum, which is also found in ancient samples. Chrysocolla, malachite, and altered Egyptian blue/green are the possible candidates for the green particle. 相似文献
13.
《文物保护研究》2013,58(1):104-111
AbstractValence House Museum (Dagenham, England) has, since 1963, housed not only a large collection of Fanshawe family portraits but also a very rich family archive which comprises estate and private papers from the sixteenth to the twentieth centuries of at least two branches of the family. Of national and international interest are the papers of Sir Richard Fanshawe (1608-66) relating to his three embassies to the Iberian peninsula in the 1660s. Three documents from this collection were taken for conservation and treated using both aqueous and non-aqueous methods of deacidification. Prior to treatment, the papers were characterized using the techniques of scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), electron spectroscopy for chemical analysis (ESCA or XPS), thermogravimetry (TGA) and thermomechanical analysis (TMA and DLTMA). Measurements showed that the three papers were similar in composition and were basically cellulosic materials with varying trace levels of Fe and Cu impurities. All three documents contained iron gall ink; the ink of the Dublin letter had an additional feature in the form of small bright specks which were characterized as a form of mica. After conservation treatment the papers were examined using the above techniques in an attempt both to determine and to quantify any changes which had occurred during the treatment process. Scanning electron micrographs showed that pronounced changes had occurred in the surfaces of the treated papers. With XPS it was possible to measure the change in the surface composition of the papers which occurred on treatlp.ent. It was also found that the treatment reduced the thermal stability of the papers in all three cases. 相似文献
14.
Iron ore as pozzolanic filler is an uncommon constituent of historic plaster rarely reported in any research. This paper presents one such study from western India where hematite instead of crushed bricks was identified as admixture in thirteenth–sixteenth-century CE Mughal masonry lime works of Daulatabad Fort. The outer/inner coat plasters from different locations of the fort were examined for morphological, mineralogical, chemical, and basic physical properties. The analytical investigative study was performed by optical microscopy, sieve analysis, X-ray fluorescence, X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, SEM-EDX, and thermal analyzer. Although the plaster is dominantly made of micritic calcite and aggregate, incorporation of gypsum in the outer and inner coats has been detected and probably acted as a second binder. Cannabis sativa was mixed in the plaster, pointing to the knowledge of hempcrete technology by the makers of Daulatabad Fort. This investigation has now provided essential information with enough precision about this historic plaster for formulation of compatible repair materials essential for the site restoration. 相似文献
15.
National Museums Scotland has collections relating to many areas of science and technology, including medical science. This paper considers technical and conservation issues of an important collection of more than 150 prosthetic limbs. Much of the collection is of prosthetics developed for children born lacking or with malformed upper limbs caused by the prenatal morning sickness drug Thalidomide. However, many other examples are represented and the collection showcases a timeline of bioengineering development covering the past five decades. A wide range of plastics and metals were observed within the pieces examined, with many visibly degraded and degrading. The identification and characterization of these materials and their condition are fundamental to interpreting the development of the collection, for deciding on treatment, and for setting a strategy for future preservation. In addition to visual inspection, three analytical techniques were used to examine the various parts of the selected examples: Fourier transform infrared spectroscopy for polymer identification and condition; X-ray fluorescence spectroscopy to identify the metals and alloys present, and X-radiography to reveal the internal mechanisms of the limbs. Interpretation of the results was greatly enhanced by documentation and conversation with engineers and scientists involved in research and development of the limbs. The combination of different materials, some with conflicting environmental requirements, makes storage and display challenging as the goal is to prevent degradation of any part the object. Some objects were found to be actively degrading and for these separate storage solutions have been recommended to slow the emission of volatile degradation products that would cause further damage throughout the collection. 相似文献
16.
Martin Nordvig Mortensen Gilles Chaumat Francesca Gambineri Hartmut Kutzke Jeannette Jacqueline Łucejko Caitlin M. A. McQueen 《文物保护研究》2013,58(2):115-123
ABSTRACTSamples of conserved archaeological wood of different ages, origins, and conservation histories were aged in a climate chamber for seven months, while the humidity alternated between 30% RH for 12 hours and 80% RH for 12 hours at a constant temperature of 30°C. Photographs were taken once every hour, which enabled the creation of a time-lapse movie. Some samples degraded visibly, whereas others were unaffected. Most of the samples were robust and would be able to survive well even in a very poor museum climate. Among the sensitive samples, three types of degradation were identified, namely disintegration, pyrite oxidation, and efflorescence of white crystals. Disintegration was ascribed to dimensional changes caused by the RH alternations in very fragile wood. The white efflorescence was interpreted as the recrystallization of an alum-associated substance, possibly mercallite (KHSO4). The pyrite oxidation was observed as the efflorescence of a thick yellow, grey, and green powder. Characterization of selected samples was performed using X-ray fluorescence spectrometry, X-ray diffraction spectrometry, scanning electron microscopy with energy dispersive X-ray spectroscopy, inductively coupled plasma – optical emission spectroscopy, Fourier transform infrared spectroscopy, ionic conductivity – liquid chromatography, and pyrolysis-gas chromatography-mass spectrometry with in situ silylation using hexamethyldisilazane. 相似文献
17.
《文物保护研究》2013,58(2):125-134
AbstractA small but significant proportion of the archaeological iron objects in the British Museum collection have been problematic in that some of them have required repeated treatment. The deterioration of iron objects during storage was studied using microscopy, Raman spectroscopy, X-ray diffraction, scanning electron microscopy/energy dispersive X-ray analysis, X-ray fluorescence spectroscopy and ion chromatography. A total of 125 iron objects, including 56 from two British Roman sites and 69 from three Anglo-Saxon sites, were studied. Both surface corrosion and corrosion layers on polished cross-sections were investigated. The study revealed that the present condition of the iron objects varies; some are in a stable condition and others have been deteriorating, with pitting and weeping present on the surface. No treatment method had stopped corrosion for every object, although the alkaline sulphite treatment seemed to be more effective than the other methods. The results also showed that chloride ions can be present at the interface of the metal and inner corrosion layers. It is recommended that iron objects which have been mechanically cleaned without desalination treatments are kept in a dry environment to prevent further deterioration. 相似文献
18.
《文物保护研究》2013,58(3):95-109
AbstractDuring the Italian Renaissance wax was used to produce polychrome relief portraits on a miniature scale. This use of wax as a material for finished sculpture was subsequently adapted to the production of tableaux, of anatomical models, of life-size wax-works and of wax dolls. This article gives a brief account of the techniques of this type of sculpture and describes problems of conservation and restoration. Methods of repairing, cleaning and restoration are discussed, and the article concludes with a full account of the restoration work carried out on an allegorical tableau by Gaetano Zumbo and on two 17th-century ecclesiastical dolls. 相似文献
19.
ABSTRACT This article is a collection of short pieces by various authors containing hints, tips and best practices reguarding Adobe Acrobat and its constituent pieces including Adobe Capture. Ariel, interlibrary loan and electronic reserve applications are included. 相似文献
20.
A technical study was conducted on a group of copper alloy artifacts excavated from the burial tumulus of Lofkënd (fourteenth–ninth century BCE) to identify the alloy compositions and methods of manufacture. The surface corrosion was also examined in order to understand the diagenetic processes affecting the preservation of the finds and their condition. Portable X-ray fluorescence spectroscopy, metallographic examination, and X-ray powder diffraction (XRD) analysis were used to characterize the alloy composition and identify the corrosion products present. XRD analysis showed the presence of brochantite (Cu4SO4(OH)6) on five of the metallic artifacts. Brochantite is not commonly reported on archaeological bronzes from terrestrial sites, but is more readily found on copper alloy objects exposed to sulfur pollutants in the air or soil. The possible conditions that could have led to the formation of this corrosion on the bronzes from Lofkënd are discussed in the context of the particular burial environment found at the tumulus. 相似文献