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1.
《文物保护研究》2013,58(4):281-297
Abstract

Cellulose poultices are frequently used in stone and wall painting conservation for the purposes of soluble salt extraction, consolidation and cleaning. They have the reputation of being easy and pleasant to work with, have a neutral pH, high water absorption and plasticity, exhibit good conformance and adhesion to the substrate, and in most cases leave minimal residues after clearance. The cellulosic materials from which they are composed range from cotton wool, blotting paper or newspaper, to cellulose powders, the latter now by far the most common form of cellulose used today by conservators. Drawbacks of these products include poor water retention when applied to vertical surfaces, a tendency to redistribute salts further into the object substrate, and poor long-term treatment effectiveness for salt extraction. Hence cellulose poultices are used frequently due to good working properties, but apparently are in some situations not very effective. In this paper, existing knowledge of these poultices is outlined, followed by investigations undertaken to fill some of the knowledge gaps. Investigations include characterization of poultice properties such as pore size distribution and workability, and of moisture transport processes within poultice/substrate systems including moisture penetration depth, moisture distribution, and poultice shrinkage during drying. Cellulose powder products known under the trade name Arbocel®, extensively tested and used in conservation over several decades, were a particular focus. Resulting guidelines include counter-intuitive measures such as (when used for salt extraction purposes) the use of thinner poultices to reduce drying shrinkage and salt redistribution further into the substrate. The relatively uniform pore size distribution (around 10 μm) of Arbocel® poultices makes them more appropriate for salt extraction on substrates with a medium-coarse pore size (i.e. 15 μm and above), while on fine porous substrates (10 μm and below), the extraction will not be as efficient.  相似文献   

2.
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   

3.
Summary

At the archaeological site of Gordion, Turkey, all registered ceramics are routinely desalinated. The standard desalination treatment was investigated by the author with a view to minimizing damage to the ceramics, as well as the amount of water used and the time taken for desalination. An equation that standardizes conductivity measurements in disparate desalination situations is presented. A series of experiments was performed to clarify the behavior of salts at Gordion. Two variables which directly affect the amount of water needed for desalination were considered: the frequency of water changes and the weight-to-volume ratio. The experimental results were compared to on-site experience, and a revised endpoint for desalination is proposed.  相似文献   

4.
Despite substantial literature on the dyeing of textiles, there is a lack of research about colouring Japanese mending papers (tissue papers) used for paper conservation purposes. This study investigates the fungal bioreceptivity of Japanese tissue papers after they have been treated with various dyes and pigments. A variety of toning materials including plant dyes, watercolours, acrylic paints, inks, pastels, gouaches, and colour pencils are commonly used by conservators for paper toning purposes. In this study, two Japanese tissue papers (Yukyu-shi and Sekishu Mare) were treated with selected plant dyes, watercolours, and acrylic paints and then inoculated with fungal species. Quantitative real-time polymerase chain reaction (qPCR) was used to quantify the DNA from Aspergillus niger and Penicillium rubrum as a proxy for fungal species abundance before and after inoculation and artificial moist heat ageing. qPCR primers which were universal for fungi amplified DNA from papers inoculated with A. niger and P. rubrum and these species were found to grow less on treated Sekishu Mare and Yukyu-shi papers compared with untreated papers. Sekishu Mare papers treated with artists' acrylic paints were found to be more resistant to fungal growth than similarly treated Yukyu-shi papers. This study suggests that for the best long-term preservation outcomes for paper materials in archives, libraries, galleries, and museums, acrylic paints generally perform better in conservation terms than most plant dyes and watercolours, although most colourants displayed some bioinhibition.  相似文献   

5.
ABSTRACT

Calcarenite stone samples from a historic building (Bizerte, Tunisia) were collected and treated under different environmental conditions with several consolidating products: alkoxysilane (ethyl silicate), a surfactant-templated novel sol–gel, Ca(OH)2, and SiO2 nanoparticles. These were subjected to marine aerosol accelerated aging cycles and studied by several non-destructive tests and techniques to assess the stability of the products. Results show that weathering caused by salt crystallization is not inhibited but it is slowed down due to the enhancement of superficial mechanical properties (surface cohesion and micro-hardness) achieved after one month of treatments application. A high or low relative humidity of the consolidation environment significantly affects the final mechanical and aesthetical physical properties and therefore conditions the durability of the treated substrates, even producing higher damage than observed in the blank specimens, depending on the product.  相似文献   

6.
《文物保护研究》2012,57(1):28-36
ABSTRACT

A pre-restoration diagnosis revealed a high amount of pyrite in the wood of the Lyon Saint-Georges 4 shipwreck (end of the second century). The occurrence of this phase is supposed to result from the microbiologically influenced corrosion of the iron fasteners. So, all the nails and metallic elements were removed from the remains before treatment and the wreck was consolidated by polyethylene glycol impregnation coupled to a specific desalination process. Treated and non-treated samples extracted from the wreck were studied in order to identify the iron/sulfur-containing compounds present in the wood before and after treatment and figure out its effect. Sample analyses relied on an original approach combining magnetic characterization methods and more common elemental and structural analysis methods. The results showed that the treatment was effective in removing soluble salts. However, a large amount of unstable iron sulfides remained inside the wood.  相似文献   

7.
《文物保护研究》2013,58(3):164-171
Abstract

With the aim of developing a new easy-to-use method for rescuing flood-damaged paper, the effect of saltwater on the inhibition of fungal growth on paper was investigated. This procedure could be used instead of, or assisted by freeze drying. Cellulose-digesting Trichoderma reesei, three types of fungi representative of fungi growing on paper (T. reesei, Aspergillus terreus, and Aureobasidium pullulans) and various naturally airborne fungi were cultured on cellulosic materials in liquid media containing artificial seawater with different salt concentrations. The addition of salts successfully inhibited the growth of T. reesei on microcrystalline cellulose at the concentration of 3.2% (m/m) or higher. The critical salt concentration, 3.2%, is within the general range of salt content in seawater. Other solutions of salts similar to sodium chloride also inhibited fungal growth. Although the observed growth-inhibiting effect was attributed to the high osmotic pressure of the salt solution, physiological effects depending on ion species used were also considered to be possible. The growth of all three types of fungi on copy paper was inhibited effectively when the salt concentration was increased. The growth of various fungi on pure cellulose, with enough oxygen supplied to pores, was completely inhibited (as assessed by visual examination) for 24 days at salt concentrations of 3.5% (m/m) or greater. The fact that the effect of saltwater on cellulosic materials was observed even under optimum medium conditions implies that fungi would be considerably inhibited on flood-damaged paper immersed in saltwater. This method is a promising first aid measure when circumstances do not allow for flood-damaged paper to be dried immediately.  相似文献   

8.
ABSTRACT

The surface texture of a stone represents a sensitive parameter in evaluating its conservation state. In monuments and sculptures, in fact, external agents continuously alter the appearance of stones, determining peculiar weathering patterns and modifying properties such as retention of water and particles, interaction with light, color, and finishing. The application of protective coatings also determines changes in surface appearance of a stone, usually evaluated and monitored by color change tests. Surface metrology methods offer the possibility to quantify these changes, evaluating the impact of external agents (natural, i.e. weathering, and artificially, i.e. protective coatings) on natural stones. In this research, we demonstrate the potential of surface areal measurements in describing the evolution of weathering processes and the effects of protective treatments on porous stone materials. The obtained results suggest that the extent of the modifications is related to the scale of observation (small- vs. large-scale undulations, i.e. roughness and waviness, respectively), with an overall increase of surface roughness as the weathering proceeds. Unexpectedly, coatings based on nanoparticle dispersions increase the topographic height parameters, due to the absence of a homogeneous film.  相似文献   

9.
《文物保护研究》2013,58(3):163-170
Abstract

There is a need for a simple, rapid method which can be used with a minimum of equipment to evaluate whether microbial populations may pose a potential risk to the integrity of stone incorporated into buildings and works of art. Fluorescein diacetate (FDA) and 2-(4-iodophenyl)-3-(4-nitrophenyl)-5-phenyl tetrazolium chloride (INT) were compared for detection of microbial activity on stone, using both pure cultures of bacteria from stone and also natural stone samples. Both compounds could detect activity of bacteria and other microorganisms isolated from stone. INT-formazan was produced only by intact microorganisms whereas FDA was cleaved by extracellular enzymes as well. Use of FDA with stone samples was successful but INT required extended incubation times which gave little indication of in situ activity. A positive correlation was found between rapid cleavage of large amounts (> 15μg per gram stone) of FDA and production of INT-formazan after extended incubation periods. FDA was therefore found to be more appropriate as an indirect measure of metabolic activity of microbial populations on stone. The simplicity of the method makes it suitable for use by non-scientific personnel, with a minimum of scientific equipment, to identify stones at risk from active microbial populations.  相似文献   

10.
《文物保护研究》2013,58(4):298-313
Abstract

Five different methods for cleaning the limestone façades on what was originally the Workers Hospital in Madrid are analyzed in this paper. Due to the pollution in the surrounding air, just 20 years after a prior cleaning operation, sulfate crusts had developed on the entire stone surface of the building. The gypsum mortar used in the original masonry constituted an additional source of sulfur. Limestone is a traditional building material in Madrid and its surroundings. The petrography, mineralogy and petrophysical properties of the biomicrite, pelmicrite and biopelmicrite varieties of limestone identified in the hospital walls were determined. Analysis of a black layer on the stone surface showed that it consisted primarily of sulfate crusts. The cleaning methods tested were alkaline gels (sodium hydroxide and potassium hydroxide), pressurized hot water, glass bead blasting and latex peeling. The criteria for assessing the effectiveness and potential risks of the various cleaning systems included changes in the chromatic parameters of the stone, the formation of alteration products (i.e. salts) and modification of the stone surface. The stones cleaned with the three most effective methods, together with a rain-washed stone as a reference, were washed with water to generate an artificial runoff. The collected drain water was analyzed to determine the presence of any by-products from the cleaning process. The method found to be most effective and which caused the least alteration to the stone surface was glass bead blasting, particularly after adjustment of the bead size and pressure conditions used for the test.  相似文献   

11.
《文物保护研究》2013,58(2):105-112
Abstract

The degradation of coupled building stones has been simulated in a laboratory chamber using an artificial acid rain solution (‘wet’ deposition) with wet/dry cycling. The reaction of individual and coupled stones with the artificial acid rain was assessed from the pH, and confirmed by measurement of calcium ion content in the run-off. For the coupled stones, it is evident that there is a build up of damaging reaction products in the region of the lower stone closely adjacent to the upper stone. This behaviour is related to the increased time of wetness due to retained solution, containing calcium ions from runoff and anion species from the artificial acid rain solution, which allows locally enhanced reaction with the lower stone and subsequent development of salts. Where Leinster granite is the lower stone of the couple, calcium ions in the run-off from the upper stone, Portland limestone, accumulate in these regions, leading to the eventual development of gypsum in the near-surface regions of the granite, with extensive resultant degradation. The laboratory chamber allows rapid ranking of various stone combinations in the couple, and early insight into the degradation process which may ultimately assist in the development of conservation procedures.  相似文献   

12.
A new appraisal method for national government records introduced in the 1990s aimed at reducing backlogs in the transfer of pre-1976 records to the National Archives of the Netherlands. Since then, appraisal and disposition decisions are based on macro analysis. Preventing new backlogs from occurring was a second goal. The socalled project PIVOT (1991–2001 and after) coordinated the introduction, development, and implementation of the new appraisal method. This article describes the objectives, method, and appraisal criteria, as well as the criticism and laborious progress of this ongoing story. This article is a revised and enlarged version of an earlier publication, “Makrohindamine Hollandis. Eskimesed kümme aanstat: 1991–2001”, TUNA Ajalookultuuri ajakiri 4 (2003): 150–154.  相似文献   

13.
ABSTRACT

Sandstone is a common sedimentary rock that is easily carved due to its weakly cemented fine grains and relatively low strength. Therefore, numerous large-scale grottoes in China are made of sandstone. However, these sandstone cultural heritage structures are often seriously damaged due to temperature and humidity changes, air pollution, biodeterioration, and repeated dissolution and crystallization of soluble salts. In general, it is imperative that a consolidant capable of providing cohesion by infilling pores between the stone grains is synthesized. In recent years, it has been reported that using organic consolidation materials for sandstone protection comes with various negative effects, such as a short lifetime, poor compatibility, and preservation damage. Using inorganic consolidation materials to protect sandstone seems to be one of the research trends for the future. Herein, this paper introduces a permeable, inorganic magnesium-based material (MMH solution) for silica sand consolidation. To assess this consolidant, the paper investigates the influence of varying molar ratios of MgO:MgCl2·6H2O:H2O on properties such as penetration depth, consolidation weight, colour variation, and compressive strength. The results demonstrate that the molar ratios of MgO:MgCl2·6H2O:H2O can significantly affect the consolidation performance. Additionally, it is believed that the MMH solution of MgO:MgCl2·6H2O:H2O?=?5:1:16 can be successfully used for the consolidation of silica sand, as the cubic specimens’ surface micrographs show good compatibility between the consolidation product and sand grains. Experiments (i.e. weight loss rate and mineralogical compositions analysis) are performed to evaluate the cubic specimens’ water resistance properties after being immersed in water. Furthermore, the consolidation material’s failure mechanism as a self-sacrificing material is preliminarily analyzed. Results indicate that MMH solution is a promising conservation material that shows great potential for consolidating severely weathered sandstone.  相似文献   

14.
none 《文物保护研究》2013,58(3):221-222
Abstract

Furunori (aged paste) is a conservation material that is used for Japanese painting conservation. Furunori is a smoother and weaker adhesive than fresh paste, and it enables the surfaces to be easily peeled apart, with application of water, in a future conservation. Due to these characteristics, furunori has traditionally been used for attaching the backing paper to paintings in Japan, because it is considered that furunori causes less stress on the paintings than fresh paste. This study aims to clarify the characteristics of furunori based on chemical analysis and examination of the microorganisms involved in the early stage of furunori generation. Based on the results obtained, a polysaccharide similar to furunori was prepared.  相似文献   

15.
Nicola Goc 《Media History》2013,19(3):322-336
In 1941 Australian tabloid journalist Dorothy Gordon Jenner was caught up in the Japanese siege of Hong Kong and was incarcerated in the Stanley Internment Camp. During her internment Jenner kept a clandestine record of daily life written in pencil on Bronco brand toilet paper and kept hidden in the heels of her shoes. To date her fragmented diary and notes have defied analysis. This paper provides a reading of Jenner's personal wartime testimonio through the frame of tabloid journalism to expose how the tabloid genre—Jenner's stock-in-trade as a journalist before the war—became the framework for her personal testimony during World War II. By interpreting Jenner's private diary and notes as testimonio journalism this paper exposes the flow of the tabloid vernacular style of journalism between private and public discourses.  相似文献   

16.
Salt crystallization is recognized as a major cause of damage to porous building materials, threatening the sustainable preservation of our valuable built heritage. Unfortunately, the crystallization behavior of the detected salt mixtures is complex and not fully understood. While the deliquescence points of single salts are well documented, this is not the case for salts in a mixture where one is confronted with the presence of different cations and anions. In this paper the salt content of the murals and the limestone tracery of the main entrance porch from the sixteenth century church of St. James in Liège, Belgium is investigated and related to the climatic conditions of its environment. Concerning the salt load, the research consists of hygroscopic moisture content measurements, quantitative ion analyses, and the prediction of phase equilibria using the thermodynamic model ECOS/RUNSALT. This model can predict the salt crystallization sequences of a particular ion mixture. The output is mathematically evaluated with collected temperature and relative humidity data, which enables the calculation of the number of salt crystallization–deliquescence cycles. The results show that even small amounts of salts can cause damage over a long period of time when the environment causes frequent cycles of crystallization–deliquescence over time. It is shown how a mixture of small amounts of (double) salts, including hygroscopic ones, can have a significant effect on the decay of historic building materials in the case of daily changing climatic conditions and periods of extreme drought. As a result, the crystallization of double salts and hygroscopic salts such as calcium nitrate cannot be ignored. The scientific method and the results are described.  相似文献   

17.
A Japanese painting on paper, in the form of a horizontal scroll from the Stibbert Museum in Florence, is being treated at the ISCR Paper Conservation Laboratory. The scroll, entitled Bamo Dōi-zu represents 33 different types of horses. Although there is no author's seal, it has been attributed to the famous Japanese artist, Kanō Sansetsu (1589–1651). Before conservation treatment, the artefact underwent technical and scientific examination in order to identify its materials and determine its conservation condition. As sampling paint layers from paintings on paper is extremely invasive, non-destructive techniques such as X-ray fluorescence spectroscopy, Raman spectroscopy, Fourier transform infrared spectroscopy, and spectrophotometry were employed. Several points from the paper support were analysed: the metal-leaf decorations, the seals and calligraphy, as well as the painted horses. Results detected and revealed a very simple palette: cinnabar (or its synthetic equivalent vermillion), shell white, carbon black, and the organic yellow gamboge. Pure gold and silver leaves were used for decorating the frontispiece. Useful information was obtained from the paper support and on its conservation conditions. Micro-destructive analyses were also performed on a few paper fragments for microscopic and scanning electron microscope equipped with an X-ray probe analysis. Results showed that materials and techniques are consistent with the Kanō School period.  相似文献   

18.
Salt decay is one of the harshest, most frequent, and more complex types of decay of porous materials in built heritage, including natural stones, ceramics, and mortars. In this article, we address the mechanism of thermal expansion, which is one of the least studied, yet most controversial, of those proposed over time to explain salt decay. We present a review of scientific literature on the topic, followed by a study of the effects of thermal expansion on a specific material, the well-known Ançã limestone. The study included experimental measurement of the linear thermal expansion coefficient of the Ançã, both in its natural state and with varying contents of sodium chloride, sodium sulphate, or sodium nitrate. The results show that this coefficient: (i) is significantly higher when the stone is contaminated with salt; and (ii) scales approximately with the amount of salt contained in the stone pores, regardless of the type of salt. Based on these results and on modelling of damage modes at the microscopic and macroscopic levels, respectively, we conclude that thermal expansion can cause powdering, disaggregation, or other types of decay consisting of internal loss of cohesion. However, it is not likely to cause exfoliation of salt-loaded layers.  相似文献   

19.
This paper reports anthropological research conducted at the Royal Ontario Museum (ROM) by the author over three years. The purpose of the research was a traditional anthropological one: to listen to visitors at length and in depth. Part One, published in Curator 46 (2), offered ethnographic data, anthropological analysis, and a marketing perspective to suggest why the visitor's point of view may seem vertiginously strange to museum personnel. It characterized the conflict between host and guest as the outcome of two competing models of culture: “preferment” and “transformation.” In Part Two, visitors' experiences of the museum serve to illuminate a shift in attitudes toward museum culture. This research establishes a typology of consumer segments and a set of strategic recommendations for freeing the museum from the preferment model without abandoning those visitors who continue to embrace it.  相似文献   

20.
[目的/意义]旨在研究科学计量方法在科技政策研究中的应用程度和范围。[方法/过程]对科学计量领域与科技政策领域的实证数据集进行关键词分析,设计二维词频分析框架,并在此基础上通过聚类分析揭示不同类型的计量与政策研究相结合的主题。[结果/结论]数据结论显示：科学计量方法在科学政策研究中的应用主要是在宏观层面,而在微观问题层面应用相对较少;一些利用科学计量方法研究的政策问题并非是科技政策领域的研究热点或核心。这种情形与科学计量学的学科特点与使用局限性有一定的关系,但如何恰当扩展和深化科学计量方法在科技政策领域的应用,以解决科技政策中的具体问题、更好地支撑科技管理与科技决策,需要引起关注。  相似文献   

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