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1.
ABSTRACT

This paper proposes a new way of interpreting particulate matter deposition indoors. The rate of deposition of dust in surfaces is presented as the result of the combination of two main factors: the concentration of suspended particles close to surfaces, and their capacity to deposit, expressed as the deposition velocity. We suggest that either of these two factors can be altered in order to mitigate deposition. The implications of this perspective are explored using in-situ measurements in a historic property (Apsley House, London) and a computational fluid dynamics model of aerosol deposition. The cases studied involve the effect of outdoor wind on the ingress of particles, the consequences of leaving the main door open, and the effects of the ventilation system on deposition. The results demonstrate that simulations can be used reliably to explore hypothetical scenarios or situations that would be experimentally challenging. The inputs and outputs of the computational model are discussed in view of its usability in preventive conservation.  相似文献   

2.
The collection of the Worcester Art Museum includes two rare Magna Graecia terracotta funerary statues from Canosa, Italy dating to the third century BCE. Each depicts a female figure in prayer or lament known as an orante. The orantes were purchased by the museum in 1927, but shortly thereafter were separated. One was left in storage for nearly seven decades and the other was sold, and ultimately entered a private collection halfway around the world. The orantes were recently reunited under serendipitous circumstances and, after more than 80 years, will finally be placed on display at the Museum. As part of a comprehensive treatment, a technical study was carried out to identify the materials and methods used in their manufacture and in previous restoration campaigns. Materials were characterized by cross-section analysis, spot tests, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), neutron activation analysis (NAA), thermogravimetric analysis (TGA), thermoluminescence (TL) dating, and reflectance transformation imaging (RTI). The analytical findings helped inform the conservation treatments, which included structural work, surface cleaning using a Nd:YAG laser, and esthetic reintegration.  相似文献   

3.
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4.
ABSTRACT

The tomb of Tutankhamen in the Valley of the Kings, Egypt, one of the major attractions of the World Heritage Site of Ancient Thebes and its Necropolis on the West Bank of modern day Luxor, is today a destination for mass tourism. Visitors to the tomb increase relative humidity, elevate carbon dioxide levels, and encourage natural ventilation which facilitates entry of dust into the tomb. These conditions negatively impact the wall paintings and remaining artifacts in the tomb and create an uncomfortable environment for visitors. The deposition of dust inside the tomb collects on uneven wall painting surfaces, obscures their legibility and necessitates cycles of cleaning, which in turn leads to further damage. Developing environmental management strategies in the tomb to counter the effects of visitors and mitigate dust entry is an important component of the collaborative project between the Getty Conservation Institute (GCI) and Egypt’s Ministry of Antiquities (MoA) to conserve the tomb. These included implementation of a filtered-air supply and exhaust ventilation system to stabilize the interior microclimate and reduce dust in order to improve visitor comfort and contribute to the long-term preservation of the tomb.  相似文献   

5.
This study focuses on the changes in properties of cellulose-based paper, which can take place as a consequence of its contamination by dust particles. The PM1 (fine) and PM10 (coarse) fractions of the dust particles from archival repositories were collected on cellulose filters Whatman 41, polytetrafluorethylene, and quartz filters. The latter two types of samples were subsequently analyzed gravimetrically, with ion chromatography, PIXE, and the thermal–optical transmission method, giving mass, ionic, elemental carbon, and organic carbon concentrations. After artificial aging, the viscosity-average degree of polymerization of cellulose (DPv) was measured. It was confirmed that cellulose-based paper can undergo substantial changes when contaminated by dust particles and artificially aged. The decrease of the DPv of cellulose showed a negative correlation with the deposited mass of sulfate ions in the dust particles. Considering the particle size fraction, the results suggest the decisive importance of the fine (PM1) particles. The results provide better understanding of how particulate matter contributes to the chemical degradation of cellulose-based paper. Such knowledge is of importance when considering appropriate conservation measures in archives, libraries, and galleries.  相似文献   

6.
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7.
《文物保护研究》2013,58(4):259-266
Abstract

During the restoration of art works, data of great significance to art history frequently emerge. The purpose of our research is to throw light on the materials used in the past in the treatment and maintenance of works in ivory and bone. This has been achieved by conducting in-depth historical research into the specific literature and, thereafter, by examining with X-ray powder diffraction analysis and DTA and TG thermal analyses the accumulated deposits in the carvings and cavities of several artifacts belonging to the ivory collection housed in the National Museum in Ravenna.  相似文献   

8.
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   

9.
The identification of painting techniques is an important aspect of any research related to historical, artistic, and conservation issues in the field of wall paintings conservation. There are a variety of different methodological approaches that can be used to identify wall painting techniques. In this study, the application of optical (PLM) and electron (SEM-EDX) microscopy was explored as they are complementary analytical techniques commonly used for micro-stratigraphic analysis of painted surfaces. Five replicas were prepared according to the technical procedures reported in medieval historical treatises, and the pigment was applied at different time intervals in order to monitor the modifications at the interface between the ground and pictorial layer. The comparison of data from the replicas with samples from Romanesque wall paintings in churches in Southern Switzerland and Northern Lombardy (Italy) allowed for an evaluation of the reliability of the proposed methodology and for the interpretation of the painting techniques.  相似文献   

10.
ABSTRACT

In August 2014, a pit containing more than 10000 porcelain shards was excavated in the southwestern area of the Palace Museum. Reign marks and other stylistic criteria dated the manufacture of these fragments from the reign of Hongwu in the Ming Dynasty (1368–98 CE) to the Guangxu reign in the Qing Dynasty (1875–1908 CE). A famille rose (fencai, 粉彩) bowl decorated with a red-ground peony pattern and having the reign mark of Qianlong (1736–96 CE) on the base was studied using several non-destructive analytical methods to determine the variation in overglaze compositions, the colorants, the application sequences, the thickness of the colored layers and the high-temperature porcelain glaze, and the identification of the surface weathering products that formed during burial. The methods include non-destructive X-ray fluorescence, Raman spectroscopy, optical stereomicroscopy, and laser confocal microscopy, as well as X-ray diffraction.  相似文献   

11.
ABSTRACT

During construction of a 6 km long railway tunnel close to historic churches in Stockholm, a preventive monitoring model was applied for ensembles of large-scale immovable ecclesiastical artworks. Construction work such as blasting and pile-driving took place during five years under or very close to these immovable works of art. In Sweden, risk assessment related to construction work is focused on risks associated with the building; meanwhile, there is no common approach for protecting the immovable historic works of art and architectural surfaces. This paper discusses how a preventive model for vibration monitoring on immovable artworks was developed and used as well as how the preventive purpose was perceived by different stakeholders during and after the tunnelling work. Experience from this project concludes that monitoring that includes uniform visual inspection becomes crucial for being able to protect the artworks. The concept of vibrations standards relying on fixed numbers of critical vibrations levels for mitigating the effects of vibration on immovable art can be questioned based on experiences from this project.  相似文献   

12.
One of the most important artistic circles in the first half of the fifteenth-century in Austria was the so-called ‘Older Villach's workshop’, founded by Frederic of Villach, a painter who was considered a master of fresco technique. A technical study was made of a number of wall painting cycles by the workshop of Frederic of Villach, first, to gain a broader knowledge of the painting techniques employed, and second, to allow comparison with a further group of wall paintings in Slovenia, which are stylistically related to this workshop and have been studied previously. Of special interest were artworks attributed to Frederic's son Johannes of Ljubljana and a number of other anonymous painters that show important similarities to Frederic's works. Samples of plasters and pigments were analysed by optical microscopy, scanning electron microscopy with energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. An important difference in the composition of plasters was discovered between the selected artistic groups. The palette used comprised predominantly earth and other mineral pigments. The construction of the paintings from incisions and preparatory drawings to the final modelling is basically similar and shows workshop connections. The principal painting technique was a fresco. The results contribute to a wider knowledge concerning the materials and techniques employed in gothic wall paintings in the Alpine region and offer new information that can be used to inform the future conservation of these selected wall paintings.  相似文献   

13.
A three-year research project at the University of Southampton (2007–2010) investigated whether monitoring techniques commonly used by engineers to assess the strength and durability of materials could be usefully applied to inform the condition assessment of historic tapestries. To date it has not been possible to obtain an objective picture of the overall condition of a tapestry; the study investigated whether it is possible to identify precursors of structural damage. The two techniques, digital image correlation (DIC) and optical fibre sensors, were used to monitor a representative wool fabric, specially woven tapestry samples, a newly woven tapestry, and historic tapestries, both in the laboratory and in situ in a historic house. This study first sets out to answer the question: can DIC be used to monitor and visualize strain in historic tapestries? It is shown that DIC can be used successfully. Secondly, it discusses the map function, a novel development which allowed the monitoring equipment to be moved, so that it could be used in situ in a historic house. Thirdly, it provides further details of the experimental work using optical fibre sensors to confirm the accuracy of the DIC technique.  相似文献   

14.
《文物保护研究》2013,58(2):97-106
Abstract

The Danish sculptor Anne Marie Carl-Nielsen (1863–1945) often prepared three-dimensional models in wax before producing her works of art. The Carl Nielsen Museum in Odense keeps a unique collection of around 200 of the artist's fragile wax models. In 2008 the entire collection was examined, documented, X-ray radiographed, photographed, and conserved. Analyses of five figurines by attenuated total reflectance-Fourier transform infrared spectroscopy, optical microscopy, and scanning electron microscopy-energy dispersive X-ray spectroscopy showed two different kinds of wax mixtures, one containing beeswax and potato or maize starch as filler, and the other consisting of gypsum, zinc stearate, and a greasy substance. During the examination a specific deterioration phenomenon was noticed in the areas where the wax models had been strengthened with internal metal armatures. A chemical reaction between the wax mixture and the copper containing armature has caused an intense greenish colouring of the wax as well as creating a soft and almost liquid consistency and formation of copper(II) carboxylate salts. Based on an original recipe from Anne Marie Carl-Nielsen, a replica of one of the wax mixtures was produced and examined with respect to its infrared spectrum and its modelling properties.  相似文献   

15.
This study applied Erwin Panofsky's concept of levels of meaning of works of art and Corinne Jorgensen's framework of image attributes to an exploration of the distinct levels of meaning perceived by children in illustrations of picture books. Observations, interviews, and surveys were used for data collection and content analysis and case study for data analysis. Thirty-one three- to five-year old children recruited from preschool, pubic library, and home school settings participated. Findings showed that children relied on their previous experience and familiarity with the literary source to achieve levels of meaning. The concept of levels of meaning could provide a better understanding of representing meaning for children and children's interpretation of meaning of visual information.  相似文献   

16.
A great number of Central Asian wall paintings, archeological materials, architectural fragments, and textiles, as well as painting fragments on silk and paper, make up the so called Turfan Collection at the Asian Art Museum in Berlin. The largest part of the collection comes from the Kucha region, a very important cultural center in the third to ninth centuries. Between 1902 and 1914, four German expeditions traveled along the northern Silk Road. During these expeditions, wall paintings were detached from their original settings in Buddhist cave complexes. This paper reports a technical study of a wall painting, existing in eight fragments, from the Buddhist cave no. 40 (Ritterhöhle). Its original painted surface is soot blackened and largely illegible. Grünwedel, leader of the first and third expeditions, described the almost complete destruction of the rediscovered temple complex and evidence of fire damage. The aim of this case study is to identify the materials used for the wall paintings. Furthermore, soot deposits as well as materials from conservation interventions were of interest. Non-invasive analyses were preferred but a limited number of samples were taken to provide more precise information on the painting technique. By employing optical and scanning electron microscopy, energy dispersive X-ray spectroscopy, micro X-ray fluorescence spectroscopy, X-ray diffraction analysis, and Raman spectroscopy, a layer sequence of earthen render, a ground layer made of gypsum, and a paint layer containing a variety of inorganic pigments were identified.  相似文献   

17.
《文物保护研究》2013,58(4):305-316
Abstract

The standing Buddha image of Jincheon in the Republic of Korea created in the fourth year of Taehwa is engraved on a darkgray rock wall of shale. The front face has a backward inclination, meeting the strike of N40°W almost vertically. The host rock contains well-developed fine laminations and stratifications, and has small and large discontinuous planes irregularly distributed. Exfoliations make it hard to make out each part of the body. The surface of the surrounding rocks is severely contaminated with lichen and Bryophyta, and plant roots aggravate the mechanical and biological weathering. The rocks went through a series of conservation treatments, which consisted of dry cleaning followed by wet cleaning using distilled water. Broken or cracked parts were filled in or glued together using epoxy resin, surfaces with exfoliations were treated with ethyl silicate to become water-repellent and hardened. The color of the repaired parts was matched to harmonize with the rest of the image. Drainage was created to divert rainwater from the slope above away from the image, and surrounding plants were removed to control lichen growth. The bedrock of the Buddha image is deteriorated in its functions due to the surface weathering, therefore it is necessary to implement long-term monitoring and to search for comprehensive conservation solutions.  相似文献   

18.
ABSTRACT

As an important part of art and culture, ancient murals depict a variety of different artistic images, and these individual images have important research value. For research purposes, it is often important to first determine the type of objects represented in a painting. However, the mural painting environment makes datasets difficult to collect, and long-term exposure leads to underlying features that are not distinct, which makes this task challenging. This study proposes a convolutional neural network model based on the classic AlexNet network model and combines it with feature fusion to automatically classify ancient mural images. Due to the lack of large-scale mural datasets, the model first expands the dataset by applying image enhancement algorithms such as scaling, brightness conversion, noise addition, and flipping; then, it extracts the underlying features (such as fresco edges) shared by the first stage of a dual channel structure. Subsequently, a second-stage deep abstraction is conducted on the features extracted by the first stage using a two-channel network, each of which has a different structure. The obtained characteristics from both channels are merged, and a loss function is constructed to obtain the classification result. This approach improves the model's robustness and feature expression ability. The model achieves an accuracy of 84.24%, a recall rate of 84.15%, and an F1-measure of 84.13% when applied to a constructed mural image dataset. Compared with the AlexNet model and other improved convolutional neural network models, the proposed model improves each evaluation index by approximately 5%, verifying the rationality and effectiveness of the model for automatic mural image classification. The mural classification model proposed in this paper comprehensively considers the influences of network width and depth and can extract rich details from mural images from multiple local channels. An effective classification method could help researchers manage and protect mural images in an orderly fashion and quickly and effectively search for target images in a digital mural library based on a specified image category, aiding mural condition monitoring and restoration efforts as well as archaeological and art historical research.  相似文献   

19.
《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   

20.
ABSTRACT

Boundary walls are neglected but important parts of historic urban environments, and they are often prone to serious deterioration. Understanding moisture and salt dynamics within boundary walls can help infer the causes and dynamics of deterioration. This investigation investigates the patterns of moisture, salt, and deterioration on a 300 year old limestone boundary wall in Worcester College, Oxford. Multiple methods to assess moisture and salts within and across the wall (electrical resistivity tomography, handheld resistivity-based moisture meter, paper pulp poultices, scanning electron microscopy, inductively coupled plasma optical emission spectrometry, and ion chromatography of small scale sampling of deteriorated limestone) were used in conjunction with decay mapping of both sides of the wall. The salt weathering strongly correlates with severely weathered zones at the wall and salts, mainly sulfates, seem to be the main agent of decay processes. The combined results demonstrate that the environmental influences driving stone decay can differ on a very small scale even at a comparatively simple structure like a boundary wall, and that repairs can have adverse effects if the patterns of salt and moisture dynamics are not sufficiently known.  相似文献   

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