共查询到20条相似文献，搜索用时 31 毫秒
1.
Roel Hendrickx Ester S.B. Ferreira Jaap J. Boon Guylaine Desmarais Dominique Derome Lora Angelova 《文物保护研究》2017,62(7):393-409
Moisture is a driving factor in the long-term mechanical deterioration of canvas paintings, as well as for a number of physico–chemical degradation processes. Since the 1990s a number of publications have addressed the equilibrium hygroscopic uptake and the hygro-mechanical deformation of linen canvas, oil paint, animal glue, and ground paint. In order to visualise and quantify the dynamic behaviour of these materials combined in a painting mock-up or reconstruction, we have performed custom-designed experiments with neutron radiography and nuclear magnetic resonance (NMR) imaging. This paper reports how both techniques were used to obtain spatially and temporally resolved information on moisture content, during alternate exposure to high and low relative humidity, or in contact with liquids of varying water activities. We observed how the canvas, which is the dominant component in terms of volumetric moisture uptake, absorbs and dries rapidly, and, due to its low vapour resistance, allows for vapour transfer towards the ground layer. Moisture desorption was generally found to be faster than absorption. The presence of sizing glue leads to a local increase of moisture content. It was observed that lining a painting with an extra canvas results in a damping effect: i.e. absorption and drying are significantly slowed down. The results obtained by NMR are complementary to neutron radiography in that they allow accurate monitoring of water ingress in contact with a liquid reservoir. Quantitative results are in good agreement with adsorption isotherms. The findings can be used for risk analysis of paintings exposed to changing micro-climates or subjected to conservation treatments using water. Future studies addressing moisture-driven deformation of paintings can make use of the proposed experimental techniques. 相似文献
2.
洛阳汉代壁画是研究汉代社会的图像资料,具有重要的文献学价值。壁画的研究成果是地方文献特色资源的一部分,图书馆运用现代化科技手段和图书馆专业管理技能,参与对汉代壁画的保护和研究成果资料的整理推广活动,建立以汉代壁画研究为中心的成果资源数据库,为传承中华优秀文化做出贡献。 相似文献
3.
ABSTRACTPanel paintings are essentially wooden boards painted on one side. Due to the vapor resistance of the paint layer, changing ambient conditions lead to exchange of moisture on only one surface. Subsequently, a non-uniform moisture content profile is formed across the thickness of the board. As a result, differential expansion causes the board to bend in case of no mechanical restriction, or it leads to a build-up of stresses inside the material if restrained. Experiments with oak boards sealed on one side and exposed to a change in the ambient relative humidity (RH) were performed. By scaling, the response of any board with different thickness can be predicted. Since the bending of the board can be described as a linear system behavior, the frequency response can be predicted based on the step response. In combination with critical strains for wood and gesso from the literature, this gives insight into allowable RH fluctuations in terms of frequency and amplitude for different board thicknesses. 相似文献
4.
Unvarnished twentieth-century oil paintings are often sensitive to aqueous swabbing, a method routinely employed by conservators for surface cleaning. This study proposes a connection between sensitivity and the presence of magnesium sulphate heptahydrate which has been identified on the surface of some of water-sensitive paintings. The probable source of magnesium is magnesium carbonate, an additive in some twentieth-century oil paints, which has reacted with atmospheric sulphur dioxide (SO2). Films made using modern manufactured paints and formulations made in the laboratory were exposed to gaseous SO2 and raised relative humidity and examined using scanning electron microscopy with energy dispersive X-ray spectroscopy and X-ray diffraction to characterize the crystalline entities. Films containing magnesium carbonate formed magnesium sulphite and sulphate hydrates. Films containing zinc oxide were also investigated. These formed zinc and sulphur containing salts. Sensitivity to swabbing with water before and after exposure was evaluated. Films that developed salts, demonstrated increased sensitivity to aqueous swabbing after exposure to SO2. Findings suggest that increased water sensitivity may be due to a combination of the formation of hygroscopic degradation products and to weakening of the paint film due to salt-induced disruption of the surface. 相似文献
5.
ABSTRACTThe impact of relative humidity (RH) and temperature variation on the mechanical behaviour of paintings on canvas was investigated, based on the various environmental recommendations that are applied by museums and institutions worldwide. Paint samples were constructed based on the works of twentieth-century artists such as Soulages and Riopelle. The various samples are based on criteria such as paint media, additives, pigment type, canvas type, thickness, type of application, and drying time. Once they are fully dry, paint films behave as elastic, viscoelastic, or viscoplastic materials depending on the chemical nature of their components. These properties, as well as tensile strength, were determined by a series of tensile tests. Other samples were included, originating from discarded oil paintings on canvas from the seventeenth and nineteenth centuries. To carry out mechanical tests under controlled conditions of temperature and RH, a climatic chamber was built around the column of a universal testing machine. Samples were submitted to stress relaxation tests to observe their response to changes in environmental conditions. RH was increased from 20 to 90% and temperature from 15 to 60°C. Reactivity diagrams were drawn based on the results. The endurance limit under mechanical fatigue was determined from the diagrams and helped define the risks associated with each painting type when exposed to the accepted environmental recommendations. 相似文献
6.
洛阳汉代壁画是研究汉代社会的图像资料,具有重要的文献学价值。壁画的研究成果是地方文献特色资源的一部分,图书馆运用现代化科技手段和图书馆专业管理技能,参与对汉代壁画的保护和研究成果资料的整理推广活动,建立以汉代壁画研究为中心的成果资源数据库,为传承中华优秀文化做出贡献。 相似文献
7.
《文物保护研究》2013,58(1):30-40
AbstractThe Kitora tumulus, which is thought to have been built around the late seventh to early eighth century, has beautiful mural paintings which were executed directly on a very thin layer of plaster in the stone chamber. When the paintings were found, the plaster was partly detached from the stone wall and the murals were therefore considered to be likely to fall off the wall with a casual touch or stimulation. Therefore, it was decided to detach the mural paintings and to store them flat and under controlled environmental conditions. This was initiated immediately after the excavation of the tumulus in 2004. However, fungal growth and biofilm development were observed within the stone chamber during the relocation work. In 2005, small holes containing black substances were observed on certain areas of the ceiling plaster, and following investigation an acetic acid bacterium, Gluconacetobacter sp., was isolated from the black substances. The bacterium was also isolated from the ceiling, floor, and east wall in the stone chamber in 2008 after the relocation of most of the paintings had been completed. These bacteria were shown to decompose calcium carbonate (CaCO3), one of the primary components of the plaster, and to produce organic acids such as acetic acid. Additionally, they were observed to decrease the pH of the culture media significantly in the presence of ethanol and glucose. This is the first example of the characterization of acetic acid bacteria isolated from decayed plaster paintings, and it is likely that microbes such as these bacteria have been involved in the deterioration of the plaster. Chemicals to treat microbes in the Kitora tumulus during the relocation work were selected on the basis of their antimicrobial efficacy, low potential to cause adverse effects on the paintings, and low level of toxicity to humans, depending on the condition of the plaster or stone in each area. However, some chemicals, especially ethanol, may act as a carbon source, which could encourage the growth of microbes and thereby the production of acids by the microbes when diluted to a low concentration or in a degraded state. Moreover, prior contamination by other microbial species in the form of a biofilm could also encourage the growth of the acetic acid bacteria by providing low-molecular-weight organic materials as a nutrient source. 相似文献
8.
It has often been observed anecdotally and implied through experimentation that acrylic emulsion paintings accumulate and entrain soils over time due to the inherent mechanical softness in artist's acrylic paint films, through the presence of hydrophilic film components, and by virtue of the ubiquitous presence of surfactant moieties on these film surfaces once they dry. In the present study, it has been this last effect that we have sought to describe more fully in terms of surfactant responsiveness to both temperature and relative humidity (RH). Surfactant hydration and dehydration under varying temperature and RH conditions affects the ultimate partitioning of the surfactant at the paint–air interface, as well as the inherent size, aggregation tendencies, and solubility of surfactant in the bulk paint materials which contain components that are highly responsive to changes in temperature and RH (e.g. polyacrylic or polymaleic anhydride-type dispersal materials). In this work, analytical techniques including three-dimensional microscopy and quartz crystal microbalance with dissipation were used to add to and reinforce current understanding of the physical and mechanical changes to acrylic paint films with temperature and RH. The migration of surfactant at the film surface was studied using desorption electrospray ionization-mass spectrometry and attenuated total reflectance Fourier transform infrared microscopy. 相似文献
9.
ABSTRACTIn the Mogao Grottoes of Dunhuang, China, the ambient relative humidity (RH) fluctuation in the caves is the main cause for the deterioration that has been observed, especially the deterioration of the earthen plaster and wall paintings linked to the presence of NaCl and Na2SO4 salt contaminants. To help identify the mechanism responsible for this salt-related deterioration and provide a theoretical basis for the development of a preventive conservation regime, this study addressed the basic moisture adsorption mechanisms of earthen plaster with soluble salts by taking an experimental approach. It is shown that, as ambient RH increases, the moisture adsorption process of the plaster containing the soluble salts can be regarded to have three basic stages, as evidenced by the results of the moisture adsorption tests performed on earthen plaster samples with different NaCl or Na2SO4 contents at various humidity levels. The moisture adsorption mechanism and its determining factors at each stage are also analysed. In addition, it is suggested that the hygroscopicity of the plaster structure and the interaction between the different kinds of salts in the plaster, which makes the dissolution or hydration of the salt in the plaster pores much easier, should be considered more seriously regarding increases in the ambient RH in the caves. 相似文献
10.
《文物保护研究》2013,58(4):269-277
Abstractsimple mathematical model is presented that predicts the decay time of the internal relative humidity (RH) of backboard-protected canvas paintings when subjected to external RH fluctuations. The model takes into account the permeance of the canvas and the hygroscopicity of the enclosed materials. Predictions from the model are tested experimentally. The wooden stretcher releases moisture more slowly than expected, providing less buffering than predicted by the model. The practical implications of these findings are discussed. 相似文献
11.
刘兰芝 《图书馆工作与研究》2011,(6):78-80
洛阳汉代壁画是汉代文化的一个组成部分,它以鲜明的时代特征、生动的形象塑造,大气磅礴的艺术风格,深刻反映汉代社会的理想追求和精神面貌,是研究汉代社会历史的图像资料,具有重要的文献学价值。洛阳汉代壁画对古代文献具有考证价值,对于汉代的制度、文献、法律有考证、校勘价值,对于汉代社会创造的文化又因历史原因遗失部分提供补遗功能。 相似文献
12.
《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
13.
Karin Catenazzi 《文物保护研究》2017,62(2):96-103
Funori is a polysaccharide-based adhesive extracted from seaweeds and is generally used in the conservation of easel paintings for the consolidation of matte paint. It is appreciated since it does not change the optical properties of the consolidated materials and its mechanical properties do not change with ageing. Because of these characteristics, this research focused on the evaluation of Funori as a suitable material for the consolidation of powdering paint layers in wall paintings. Tests were carried out where Funori was applied onto painted plaster replicas, which were then artificially aged and investigated in order to evaluate the material's behaviour according to the specific properties and conditions of wall paintings. The effectiveness of the consolidation was evaluated from the point of view of adhesive power, as well as the interactions of Funori with some physical properties of the consolidated painting, such as colour and water vapour permeability and, therefore, its resistance to accelerated ageing and biological colonization. In addition, the behaviour of Funori applied on plasters contaminated with soluble salts, a frequent condition in wall paintings, was also evaluated. 相似文献
14.
Leszek Krzemień Michał Łukomski Łukasz Bratasz Roman Kozłowski Marion F. Mecklenburg 《文物保护研究》2016,61(6):324-330
The drying shrinkage accumulation from exposure of freshly prepared gesso layers to relative humidity (RH) cycles was determined to elucidate the mechanism of craquelure pattern formation on panel paintings. The progresive drying shrinkage of the gesso is observed only under the cycles going to high RH levels which bring about transitions from brittle to ductile state of the material. The first incidence of fracture on the gesso layers occurred after a limited number of cycles ranging between a few and 100 for a range of layer thickness between 0.5 and 1?mm. The craquelure patterns stabilised also after a limited number of cycles (30 for the 1-mm thick layer). Upon increase in the gesso layer thickness, the strength of the layer is reduced and the spacing of shrinkage fractures increases. The study demonstrated that craquelure patterns, mimicking historical ones, can be realistically produced in laboratory conditions. Such studies would provide useful information for preparing specimens simulating historic panel paintings and would inform the current efforts on automatic, computer-aided classifications of crack formations on paintings. 相似文献
15.
The work reported here is a systematic study to evaluate the compatibility of using PS-F (potassium silicate with high modulus – fly ash) slurry in the conservation of adobe structures. Firstly, the optimum mixing proportion (0.47) was determined by flow meter. Then the experimental program was divided into two parts: one part studied changes in physical and mechanical properties with increase in setting time by means of the measurement of moisture content, compressive and flexural strength, elastic-wave velocity, density, and porosity; the other part studied the durability of PS-F slurry through temperature and humidity cycles, freeze–thaw cycles, water stability, tensile testing, and alkali resistivity tests. The results show that the consolidation process with the slurry can meet the requirements of conservation applications and provide a timely anchoring force, and the slurry and soil mass of adobe-based structures have good compatibility in physical and mechanical properties. In addition, the slurry can strongly resist freeze–thaw cycles, temperature-moisture cycles, and tensile stress and has a relatively weak resistance to alkali solutions and water immersion. In conclusion, PS-F with a mixing ratio of 0.47 is a suitable slurry for conservation of adobe structures. 相似文献
16.
Poul Klenz Larsen 《文物保护研究》2018,63(5):164-169
ABSTRACTHistoric buildings in Denmark have a high relative humidity (RH) all year, so the interiors are exposed to biological degradation. The acceptable range for RH is 60–70%, which is higher than the usual recommendations for museums and galleries. There are two options for humidity control: conservation heating or mechanical dehumidification. Calculation of the energy performance of a generic building was used to determine which method is the most efficient. Studies of a cottage in Liselund Park, and of two medieval churches in Hellerup and Vemb have confirmed these predictions: dehumidification is less energy consuming than conservation heating in buildings with poor thermal insulation and a moderate air infiltration rate (AER?<?0.6?h?1). Dehumidification is suitable for historic buildings, where heating is not needed for human comfort. A condensing dehumidifier uses less than half the energy per kg water compared to an absorption dehumidifier. But it does not work at temperatures below 2°C. The combination of a condensing dehumidifier and a little heating to prevent frost is the most energy efficient solution for humidity control. These results are only valid in mild and humid climatic conditions similar to Denmark. 相似文献
17.
S. A. Dobrusina S. I. Ganicheva I. G. Tikhonova T. D. Velikova P. E. Zavalishin 《Scientific and Technical Information Processing》2007,34(5):258-263
In this work, experimental results on the influence of high temperature and relative air humidity on the aging dynamics of recordable DVDs of the R+ and R? formats of the most well-known trademarks (Sony, TDK, Imation, Digitex, Mirex, Verbatim, Philips, Fujifilm) are presented. The state of disks and recorded information is estimated qualitatively and quantitatively by computer testing using special software. Relative longevity is calculated using results on the artificial aging of compact disc specimens in harsh conditions (a temperature of + 80°C, a relative air humidity of 85%), the “stability series” of DVD±R discs of different trademarks is established. Recommendations on the practical application of DVD discs of R+ and R? formats of particular trademarks for durable storage of scientific-technical information are given on the basis of the obtained data. 相似文献
18.
《文物保护研究》2013,58(3):109-116
AbstractIvory can undergo severe cracking and splitting when exposed to adverse environmental conditions. The anisotropic dimensional properties of ivory have been investigated under varied temperature and relative humidity conditions. Migration of moisture into and out of ivory was found to play the principal role in its expansion and contraction. To control the resultant swelling and shrinking, the use of polymer coatings and waxes to act as moisture barriers was examined. A particularly effective polyvinylidene chloride emulsion was further tested for facility of application and aesthetic appearance. The incorporation of plasticizers into ivory to reduce brittleness and thereby relieve stress was also investigated. 相似文献
19.
《文物保护研究》2013,58(4):211-230
AbstractCradle-related effects, such as ‘washboarding’ and tented flaking, were investigated by computer-aided moiré fringe analysis of panel models subjected to cycled changes in relative humidity. In-plane and out-of-plane displacements were recorded and compared for cradled and unreinforced panel models. These results were related to the behaviour of actual cradled panel paintings. Results indicate that restraint of warping increases in-plane strain due to swelling, and the strain distribution is in close correspondence with cradle restraint. Compressive strain, recorded over the fixed battens, and out-of-plane distortions in the exposed panel areas are discussed in relation to deformations and damages in cradled panel paintings. 相似文献
20.
《文物保护研究》2013,58(4):167-171
AbstractA miniature low-pressure apparatus for localized treatment of paintings is described. Alternative working surfaces are available which allow heat and moisture treatment on canvas paintings without removal from their stretchers. Other applications of the apparatus are discussed. 相似文献