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1.
《文物保护研究》2013,58(3):186-203
Abstract

Safflower red was prepared by extracting safflower petals (carthamus tinctorius L.) at alkaline pH, after the preliminary removal of water-soluble safflower yellow. Alkaline extracts were used to prepare dyed silk, wool, cotton and paper, to precipitate the pigment, to prepare paint and to produce the antique Chinese cosmetic rouge. All reference samples were analyzed with high-performance liquid chromatography–photodiode array–mass spectrometric detection (HPLC-PDA-MS) after colorant was removed from its substrate by both a harsh and mild acid hydrolysis method. In addition to the red colorant carthamin, four colorless components are markers for safflower. These components were characterized by their retention times, ultraviolet–visible (UV-Vis) spectra and mass spectra and were given the codes Ct1, Ct2, Ct3 and Ct4. Experiments on references clearly indicated that these Ct components, unlike carthamin, withstood harsh acid hydrolysis as well as light-induced accelerated ageing, and that they could be found even in a completely faded wool sample. This made them excellent markers to identify safflower red, even in discolored historical samples or in samples that must be treated in a way that destroys carthamin. These findings may contribute to a better understanding of the manufacturing technology and to better conservation of objects that have already undergone considerable light-induced ageing.  相似文献   

2.
ABSTRACT

The aim of this research was to produce reference data for the study and identification of fibres of carbonised excavated textiles. Thus, the effects of carbonisation (incomplete burning) on the morphology and dimensions of selected fibres used in textile production were investigated. A set of standard test, commercial, and hand-made fabrics, of four cellulosic (cotton, flax, hemp, nettle) and two proteinaceous (silk, wool/ wool felt) fibres, were used for the experiments. Samples were carbonised in a limited oxygen environment at 250, 350, and 500°C for one hour (apart from the wool samples for which the duration of the experiment had to be lowered to six minutes). Wool and silk samples were destroyed at temperatures above 250°C. All cellulosic and the silk samples shrank and their weight was reduced at different percentages that increased as the temperature increased. Exceptionally, wool textile samples exhibited extreme shrinkage but also an increase in their weight. Similarly, the fibre diameters of the cellulosic and silk fibres shrunk gradually at different degrees as the temperature increased, and some exhibited marked degradation patterns, like lacerations in flax, ridges in hemp, raggedness in nettle, and cracks in silk fibres. Wool fibres swell locally but retained the scale pattern on the surface. In general, an increase in the weave count of the textile samples was observed. However, the morphology of the fibres characteristic to their identification did not alter to an unrecognisable degree as a result of artificial carbonisation, as long as the material was preserved.  相似文献   

3.
《文物保护研究》2013,58(2):143-144
Abstract

Oil paints dry by polymerization. This 'drying' process may be substantially complete and the surface of the paint film dry to the touch within weeks, but measurable changes continue for years. Other, slower processes also continue, primarily hydrolysis of glyceride esters. This produces carboxylic acid groups as either free fatty acids (in the case of acid groups that have not reacted otherwise) or acid groups bound to the crosslinked oil matrix (in the case of acid groups that have engaged in polymerization reactions). These may react with pigments to form carboxylate salts (called soaps in the case of a fatty acid). These changes affect the physical properties of the paint and the way that conservation treatments affect it. This paper examines the extent of hydrolysis and soap formation in some naturally aged drying oil and paint films, the extractability of these materials in organic solvents, and measured and predicted changes over time in the physical properties of naturally aged paint films. Long-term physical and mechanical changes due to aging are minor compared to those produced by overcleaning or excessive exposure to heat.  相似文献   

4.
《文物保护研究》2013,58(1):9-20
Abstract

Deterioration of paintings is effected by chemical, physical and biological agents. Activity of these agents generates mechanical stresses which result in cracking, cupping, cleavage and flaking of the paint film. Internal mechanical stress appears to be primarily responsible for premature or drying cracks in paint. Stresses external to the paint cause age cracks which penetrate both paint and ground. The literature explaining the origin and characteristics of these cracks is reviewed. Although premature cracking can only be avoided by instructing the artist in proper use of materials, age or mechanical cracking can presently be prevented by environmental controls and careful handling. Present methods of reinforcement of paintings in general only partially stabilize them against environmentally generated stresses. Further research appears necessary for more complete understanding of the stresses old paint can withstand and of the forces exerted by the shrinking and swelling of textile and wooden supports. Search for and testing of more physically and chemically inert support materials are suggested.  相似文献   

5.
《文物保护研究》2013,58(3):134-142
Abstract

Naturally occurring pigments used by Aborigines in rock paintings have been collected in Western Australia. They area red pigment (mainly hematite, Fe2O3)(from a red ochre mine worked until historic times by Aborigines, and a white pigment (huntite, Mg3Ca(CO3)4) which is still collected and used by Aborigines. Samples were also taken from rock paintings in which these pigments were used or were thought to have been used. The pigment samples were analysed to establish chemical, mineralogical, and physical properties. The paint samples were examined microscopically and with an electron probe to study their relationship with the rock surface and with other paint layers. The relationship between the pigments’ properties and their durability is discussed.  相似文献   

6.
《文物保护研究》2013,58(4):308-313
Abstract

The oak timbers of the Swedish warship Vasa are deteriorating. High amounts of oxalic acid have been found along with a low pH and low molecular weight cellulose deep in the wood timbers. The iron-rich surface wood differs from the interior wood in that it displays higher pH and cellulose with higher molecular weight. The objective of this study was to determine why there is a difference in cellulose degradation, pH, and oxalic acid amount between the surface region and the interior of the Vasa timbers. Analysis of cellulose weight average molecular weight by size exclusion chromatography was performed, as well as quantification of oxalic acid and iron by high-performance anion exchange chromatography and atomic emission spectroscopy, respectively. It was found that a decrease in iron content coincides with an increase in oxalic acid concentration and a drop in pH at a certain depth from the wood surface. When iron-rich surface wood samples from the Vasa were mixed with an aqueous solution of oxalic acid, a fast increase of pH over time was observed. Neither interior wood poor in iron nor the fresh oak reference showed the same neutralizing effect during the time of measurement. This indicates that the presence of iron (rust) causes a neutralization of the wood, through the formation of iron(III) oxalato complexes, thus protecting the wood from oxalic acid hydrolysis. This effect was not observed to the same extent for other acids observed in Vasa wood (sulfuric, formic, glycolic, and acetic acids).  相似文献   

7.
ABSTRACT

Twentieth century paints often contain titanium dioxide and zinc oxide based white pigments that can range from photostable to highly photocatalytic. Photocatalytic pigments can cause the degradation of paint upon UV exposure, whereas photostable pigments may be benign or can protect paintings from degradation. Hence, knowing whether or not a pigment is photocatalytic is of high importance for risk assessment and the subsequent decision making process concerning storage and exposure conditions of objects. Here we present a proof of principle, focused on titanium white paints, for an easy-to-use and low-tech application of a commercial photocatalytic activity indicator ink (PAII) on embedded paint samples or cross sections. This test determines, qualitatively, if a photocatalytic pigment is present in a white paint sample. The PAII paint sample staining application shows an obvious color change, within five minutes of UV irradiation, for paint samples containing photocatalytic pigments. A microscope with a camera and a UV source are the only necessary equipment for the application of this method. A quantitative image processing protocol is also proposed as an extension of the staining method by applying open source software analysis to measure the color change using photographs. The test was evaluated on reference paints with well-characterized pigments and applied on samples from modern paintings by Piet Mondriaan, Robert Ryman, and Lucebert, indicating the presence of harmful photocatalytic pigments in these cases. The novel application of a commercial ink on paint samples offers a simple test, not just for assessment of photocatalytic activity of titanium white pigments, but which may in future be applied for the detection of photoactive forms of zinc white and other potentially harmful semiconductor pigments in art objects.  相似文献   

8.
简帛文献学中文献辨伪观念和方法研究述评   总被引：1，自引：0，他引：1  
传统文献学界以静止不变的观念看待古书的形成和流传,并由此形成了一套文献辨伪方法,而简帛文献的出土则提供了古书形态和流传的真实图景,引起了学术界对于传统文献辨伪观念和方法的反思。文章述评了简帛文献学界关于文献辨伪观念和方法新的研究成果,并对文献学建设提出了一点建议。  相似文献   

9.
ABSTRACT

During the nineteenth century, chemists became increasingly engaged in the conservation treatment of polychrome surfaces. While collaborations between chemists and museum workers in charge of easel painting collections were mostly oriented towards the improvement of conservation practices, the involvement of chemists in the nascent field of archaeology was oriented towards material characterization, such as pigment analysis of polychrome surfaces. Since this type of analysis is destructive and damages the artwork, it could, therefore, be assumed that chemists were in these cases less concerned with the conservation of objects with an archaeological and historical provenance. On the contrary, my new reading of nineteenth-century English primary sources reporting pigment analysis shows that chemists also had ethical concerns about the physical integrity of archaeological objects and their conservation. This is apparent in the process in which paint samples were taken from the artworks for their subsequent analysis.  相似文献   

10.
《文物保护研究》2013,58(2):62-72
Abstract

Although smalt, a glass, might be expected to behave as a stable pigment, discolouration of smalt-containing paint layers has been observed. Early references from the literature are cited which mention the discolouration of smalt in oil media. Originally blue layers on paintings have changed into dull grey or greyish-green. Experiments suggest the following factors for this discolouration: low refractive index of the pigment compared with that of oil media; interaction of alkali content or cobalt content with oil and oleo-resinous media; the possibility of similar reactions with resin- or oil-resin varnishes in certain conditions. Discolouration may also occur if smalt is mixed with other pigments, or added as a drier or as an adulterant.

A proper understanding of the mechanism of the deterioration would require further research by more sophisticated methods.  相似文献   

11.
ABSTRACT

Conservation of an oil painting on a zinc support is a complex challenge that has not been covered in the literature. Oil paint and zinc support rarely form a working combination because of their chemical properties. This article discusses the conservation of an oil painting on a zinc support that was found in extremely bad condition due to harsh environmental conditions it had been exposed to. The object had to be consolidated due to flaking paint and cleaned of surface dirt and support corrosion products. Finally, the object had to be physically strengthened due to the weakness of the support. This process required conservators to combine methods from several different fields of the conservation discipline. Methods employed in the conservation process came less from the literature, due to the lack thereof, and more from the everyday experience of the department and vernacular working practices. The overall methodology of the process has been reconstructed and critically evaluated in the broader field of conservation ethics and the discipline as a whole.  相似文献   

12.
《文物保护研究》2013,58(3):223-225
Abstract

Sophisticated modern instruments and methods can contribute to the preservation of national and cultural heritage. Modern analytical methods such as chromatography, spectrometry and densitometry are extremely useful, particularly for the analysis of rare works of art from which only very small samples are available. This study describes the identification of the binding medium from a 200-year-old fragile silk banner using thin layer chromatography and video densitometry. The method involved the separation and identification of pure amino acids, vapour-phase hydrolysis of both the reference protein materials and the sample from the banner, and thin layer separation of the components. The separation was achieved using cellulose plates and a mixture of butanol, acetic (ethanoic) acid and water as eluent. The plates were sprayed with ninhydrin solution and then recorded by a Camag video densitometer system. The chromatograms with coloured spots were recorded under white light using a highly sensitive charge-coupled device (CCD) colour video camera. Images were acquired, processed and archived with Video Store 2 version 2.30 documentation software, and analysed using the Vista Scan program. The results for the unknown protein binder were compared with those for the standards. The experimental data identified the proteinaceous binder as an animal glue.  相似文献   

13.
This paper deals with the conservation of Roy Lichtenstein's outdoor sculpture House I, conducted at Leeum, Samsung Museum of Art, Seoul, Korea. Having suffered from direct sunlight for more than a decade, the work presented severe paint fading and chalking. The purpose of the project was to provide the best possible protection by applying a durable paint material, while simultaneously preserving the colored surface that Lichtenstein had intended. A marine paint, which is relatively durable and was also utilized by the artist himself, was selected for the repainting system. An absence of practical experience and knowledge in Korea in relation both to the marine paint and its application led to many difficulties. During the actual application of the new paint, numerous technical problems arose which had to be solved in order to carry out the conservation treatment. To meet this demand, a close adherence to technical practice and an interdisciplinary study were carried out to provide the necessary understanding and compromise.  相似文献   

14.
《文物保护研究》2012,57(1):59-64
ABSTRACT

We analyzed 53 historical textile samples from a collection of caftans and brocades dating between the sixteenth and nineteenth century in the Topkapi Palace Museum (TPM) by scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX). Data were collected on the type, dimensions, elemental composition, and level of corrosion. The technique is presented in this work as an efficient and micro-destructive tool for the characterization of the structure of historical metal threads. SEM-EDX analysis for different energies was performed on a selection of gold and silver threads belonging to the historical textiles. The results were interpreted via laboratory prepared samples of gilt Ag and sulfur reacted Ag at different thicknesses for Au and Ag2S layers respectively. A series of Au–Ag alloys for different Au/Ag ratios were prepared for comparative analysis. The threads were made of metal strips wound around a silk core. Metal wires and flat strips were also used. The use of differential energies allowed for differentiating strips and wires made of homogeneous silver and gold alloys from the ones coated with a thin gold layer. Analysis of EDX data revealed that the Au film thickness was very thin (10–60?nm). Formation of Ag2S layers over the thin Au film as thick as 1.5?µm was taking place. Formation of thinner Ag2S layers over non-gilt Ag suggested different reaction mechanisms for gilt and non-gilt cases.  相似文献   

15.
The origin(s) and role(s) of metal soaps in paints are a worldwide concern today. These hybrid compounds, containing both fatty acid chains and metals associated with a carboxylate function, are increasingly identified in paints. As reviewed in the first part of this work, the presence of metal soaps in paints is differently interpreted in scientific publications: metal soaps are sometimes considered to play a positive role as anchor points, during paint drying processes; they can also be considered as responsible for many degradation processes (protrusions, efflorescences, darkening, etc.). Their origins are also interpreted in various ways. In some paintings (in particular from the twentieth century), they have sometimes introduced on purpose, as additives, to modify the physical properties of the painting materials. In older paintings, metal soaps are usually thought to result from an uncontrolled reaction of oil with lead-based pigments, in particular lead white, red lead, and lead tin yellow. In the second part of this work, the review of historical recipes of lead-based paint shows an important number of recipes based on controlled mixing of oil with lead driers. In the third part, the experimental reproduction of such traditional recipes using walnut oil and litharge (PbO) shows that lead soaps can be formed, both in about one hour at ～100°C, or in about one month at room temperature. It shows as well that after a few years, litharge is no longer detected in the paint medium, while different lead carbonates are. Finally, the micro-infrared spectroscopy and micro-X-ray diffraction re-analysis of protrusions from a nine-year model painting shows together with lead soaps, the presence of Pb5(CO3)3(OH)2O (‘synthetic plumbonacrite’), an unusual phase recently observed in a protrusion from a painting by Vincent Van Gogh. This work highlights (i) the multiple origins and roles of metal soaps in paints and (ii) the importance of combining the analysis of fragments from historical paintings with the analysis and reproduction of historical recipes. In particular, we show that the components detected today in historical paintings may severely differ from those originally used or prepared by the painter, complicating the assessment of the painter's intentions. More than the presence of metal soaps, the key questions to be tackled should be about their origins and (re)mobilization.  相似文献   

16.
Bast fibres have been commonly used as a textile material in Northern Europe since Neolithic times. However, the process of identifying the different species has been problematic, and many important questions related to their cultural history are still unanswered. For example, a modified Herzog test and the presence of calcium oxalate crystals have both been used in identification. In order to generate more reliable results, further research and advancement in multi-methodological methods is required. This paper introduces a combination of methods which can be used to identify and distinguish flax (Linum usitatissimum), hemp (Cannabis sativa), and stinging nettle (Urtica dioica). The research material consisted of reference fibres and 25 fibre samples obtained from 12 textiles assumed to be made of nettle. The textiles were from the Finno-Ugric and Historical Collections of The National Museum of Finland. The fibre samples were studied by observing the surface characteristics and cross sections with transmitted light microscopy, and by using a modified Herzog test with polarized light, in order to identify the distinguishable features in their morphological structures. The study showed that five out of 25 samples were cotton, 16 nettle, one flax, and one hemp. Findings from two samples were inconsistent. The results show that it is possible to distinguish common north European bast fibres from each other by using a combination of microscopic methods. Furthermore, by utilizing these combined methods, new and more reliable information could be obtained from historical ethnographic textiles, which creates new vistas for the interpretation of their cultural history.  相似文献   

17.
《文物保护研究》2013,58(3):216-230
Abstract

The surfaces of acrylic emulsion (dispersion) paint films were investigated by atomic force microscopy (AFM), with supporting chemical information provided via infrared spectroscopy. The morphological and chemical features of the surfaces of a series of recently cast reference paint films were explored, including characterization of changes induced by exposure to water and mineral spirits. A portable in situ AFM system was also used to document the surfaces of acrylic emulsion paintings in Tate's collection. The complete and partial removal of migrated surfactant was successfully imaged alongside features arising from mechanical action. Differences in paint surfaces and migrated surfactant layers were observed in relation to pigment type, paint brand and exposure to accelerated ageing, in addition to applied wet surface cleaning treatments. The findings contribute to further understanding of the subtle changes occurring at acrylic emulsion paint film surfaces and are relevant to current debates on the removal/disturbance of original surface surfactant from these films through conservation treatment.  相似文献   

18.
《文物保护研究》2013,58(4):176-188
Abstract

The non-saponifiable fractions of the principal drying oils have been examined by gas and thin-layer chromatography and found to be qualitatively similar though varying in the relative amounts of sterols present. In the case of aged paint films it has been found that these sterols have largely disappeared from unpigmented films and those containing light red and lead white as pigment, though they survive quite well in the presence of verdigris. Similarly cholesterol was not found to survive well in egg tempera films. Doubt is felt as to the value of such analyses as an approach to paint medium identification.  相似文献   

19.
图书馆学研究法是从事图书馆学研究所采用的科学方式或手段,主要使用的是社会科学领域里一些常用的研究方法,有问卷调查法、统计分析法等实证性的定量方法,也有文献研究法、历史考证法、案例研究法、反思与批判法等阐释性或批判性的定性方法。图书馆学研究法与图书馆学方法论、一般学术研究法、图书馆学专门方法等概念范畴有联系更有区别。近年流行的"图书馆学专门研究方法"是一个伪学术概念,建议图书馆学界停止使用。  相似文献   

20.
Time-of-flight secondary ion mass spectrometry (ToF-SIMS) is quickly becoming a critical tool in the field of art conservation. This technique provides high-resolution spatial maps of both inorganic and organic components located within cross-sectional samples collected from works of art. With recent advances in surface analysis, ToF-SIMS can now be used to identify specific amino acids present in protein-containing materials as well as fatty acids in drying oils. For example, the detection of the ion fragment associated with the amino acid hydroxyproline can be used to confirm the use of animal glue in a paint sample. As an analytical technique, ToF-SIMS avoids the need for derivatization/silylation reagents, with no interference by the presence of pigments. Furthermore, the layered systems that are often encountered in historical paint samples remain intact throughout the analytical procedure. This allows for the co-localization of organic and inorganic species in specific layers (e.g. egg yolk paint atop a glue ground). Because of this ability to localize the analytical signal to approximately 6?µm or less, the mass spectral information can be used to produce mass-resolved and spatially-resolve images which can be correlated to previous studies of the same samples. In this study, ToF-SIMS was used to analyze a paint cross section obtained from a painting attributed to Raphael, and another from a painting by the Sienese artist Matteo di Giovanni.  相似文献   

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