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1.
《文物保护研究》2013,58(3):142-163
Abstract

Corrosion noted on a number of nineteenth and twentieth century indoor bronze sculptures in the collection of the National Gallery of Canada was the cause for a major condition survey of its Canadian, American, and European bronzes. The results led to a comprehensive study, which included material analysis. This article outlines the steps undertaken to determine the extent and type of corrosion, its possible cause(s), and potential remediation. The survey included 136 bronzes, of which 40 were selected for an in-depth study. Indoor air quality tests of the current building, housing the collection since 1988, were carried out. The dossiers and database records of the selected sculptures were reviewed to investigate their condition, treatment, and storage history. The metal, patina, and corrosion products were subjected to analysis. More areas of corrosion were generally associated with predominantly green patinas and chloride-containing compounds identified in either patina or corrosion samples. The most frequently identified compounds in the patina samples were atacamite, a copper(II) chloride hydroxide, and cuprite, a copper(I) oxide. The most frequently identified compounds in the corrosion samples were atacamite and rouaite, a copper(II) hydroxide nitrate. The analysis determined that the current environment is not contributing to the surface alterations of the sculptures; however, past storage conditions, chemical residues from artificial patination, and likely casting residues are the main causes of the current condition.  相似文献   

2.
《文物保护研究》2013,58(4):264-272
Abstract

The removal of calcareous accretions from archaeological bronzes can be a difficult step in their conservation. Chemical cleaning with chelating agents might be an alternative to mechanical methods. In this study the use of the chelating agent sodium tripolyphosphate (STPP) was examined to determine whether it is effective in discriminating between calcium carbonate and copper patina, and non-corrosive to copper alloys in the presence of air. Comparative experiments with STPP and disodium ethylenediamine-tetraacetate (Na2-EDTA) were carried out on synthetic malachite, cuprite, calcium carbonate, naturally polished malachite surfaces and sheets of bronze and brass. In addition to the properties of the chelating agent, the solubility of the salts and the pH values of the solutions are crucial factors in the removal of compounds of low solubility. The quantity of metal ions dissolved, estimated by atomic absorption spectral analysis and scanning electron microscopy, showed that the calcareous accretions could be removed satisfactorily, but STPP also dissolved constituent parts of the patina, such as malachite and cuprite, and may harm bronze or brass. Compared to Na2-EDTA, STPP is less effective in dissolving calcium carbonate. It is less harmful to the patina and base metal, but may lead to patination of the underlying metal.  相似文献   

3.
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   

4.
ABSTRACT

A data warehouse, developed for United States Department of Energy/National Nuclear Security Administration (USDOE/NNSA) Pantex Plant in a multi-department collaboration, brings data from disparate datasets and spatial information about the site together into a single database accessible through an intranet web page or ArcGIS software. The web page directs queries of buildings, facilities, and areas through a Geographic Information System (GIS) viewer that displays spatial site information and chemical hazards data. The Spatial Database Engine (ArcSDE) provides the vehicle for linking mainframe datasets, downloaded daily, to current spatial information about buildings and facilities that store chemicals of potential concern to firefighters and other emergency responders. The system is available to the plant's shift supervisors and individual GIS users throughout the department.  相似文献   

5.
none 《文物保护研究》2013,58(4):189-191
Abstract

Polyethylene glycols (PEG) can be detected in wood by their in situ formation of coloured complex compounds. Solutions of potassium bismuth iodide/barium chloride and of bromine/potassium iodide are suitable for sprayingdirectly onto wood, and may even be used on dark-coloured wood by mixing chalk powder into the reagent. By adopting a print-off technique onto damp filter paper, the distribution of PEG in wood can be demonstrated even more exactly, even from very small samples. Print-offs are developed into differentiated coloured pictures withsolutions of potassium bismuth iodide/barium chloride, iodine/potassium iodide or ammonium cobalt (II) thiocyanate.  相似文献   

6.
《文物保护研究》2013,58(4):147-152
Abstract

In order to test some of the methods of archaeological bronze conservation, a procedure was perfected that reproduces the structure and composition of original patinas. Then the most common methods of treatment were applied on test samples thus prepared and on archaeological items. This experiment has allowed us to choose the best treatment in accordance with the following requirements: restraint of corrosion, speed of operation, lack of colour alteration and avoidance of break-up or solution of patina.  相似文献   

7.
《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   

8.
《文物保护研究》2013,58(1):34-44
Abstract

Sulphuration is the main destroyer of marble, producing imaginary (not true) patina. Other reasons for the discoloration of marbles are discussed. Magnesium silicate saturated with de-ionized water is a safe and simple cleaner. Sintolite is advocated as an adhesive for marble rather than the general more fluid epoxy resins. Solid polyvinyl acetate is strongly advocated as the basis for sma1l repairs to internaIly housed marble. The consolidation of marble is discussed and a method for internal exhibits recommended. Conservation of unbaked clay is touched upon, and a method for the repair of terracotta suggested together with a process for the reproduction of a glazed frieze using a latex mould and epoxy-reinforced plaster casts. A few remarks are made concerning the dangers of cleaning alabaster with water. The commentary is of a general nature and is not intended as a strict blueprint for any particular object.  相似文献   

9.
Objective:A growing volume of studies address methods for performing systematic reviews of qualitative studies. One such methodological aspect is the conceptual framework used to structure the review question and plan the search strategy for locating relevant studies. The purpose of this case study was to evaluate the retrieval potential of each element of conceptual frameworks in qualitative systematic reviews in the health sciences.Methods:The presence of elements from conceptual frameworks in publication titles, abstracts, and controlled vocabulary in CINAHL and PubMed was analyzed using a set of qualitative reviews and their included studies as a gold standard. Using a sample of 101 publications, we determined whether particular publications could be retrieved if a specific element from the conceptual framework was used in the search strategy.Results:We found that the relative recall of conceptual framework elements varied considerably, with higher recall for patient/population (99%) and research type (97%) and lower recall for intervention/phenomenon of interest (74%), outcome (79%), and context (61%).Conclusion:The use of patient/population and research type elements had high relative recall for qualitative studies. However, other elements should be used with great care due to lower relative recall.  相似文献   

10.
Copper(II) hydroxide (as the rarely occurring mineral spertiniite) is formed under alkaline, oxidising conditions. It has been observed as a naturally occurring corrosion product of brass in sea water. But most occurrences on copper alloys are due to conservation treatments using basic solutions (sodium hydroxide or ammonia) or to intentional patination. Classical brass centrepieces (c. 1800), ‘cleaned’ with ammonia solution, developed a blue spertiniite patina in gaps, where evaporation was hindered. Additional to the danger of stress corrosion cracking this is another reason now outlawing this treatment. Copper pigment layers will transform to copper hydroxide when exposed to bases. The treatment of basic copper salts with bases has been used intentionally in the production of Bremen blue and similar pigments which can be composed of copper hydroxide as well.  相似文献   

11.
ABSTRACT

Advances in building technologies are combining energy efficiency, networked sensors, and data recording in exciting ways. Modern facilities can adjust lighting, heating, and cooling outputs to maximize efficiency, provide better physical security, improve wayfinding for occupants, and provide detailed reports of building use. This column will briefly explore the idea of “smart buildings,” describe some of the technologies that are being developed for these buildings, and explore their implications for libraries. A brief listing of selected smart building technologies is also provided.  相似文献   

12.
SUMMARY

With support from a National Endowment for the Humanities Reference Materials Program grant for 2006–2008, faculty and librarians at the University of Washington (UW) are collaborating with William Brumfield (Tulane University) to preserve and catalog the latter's unmatched collection of Russian architectural photographs, create metadata describing the photographs, and make images and text widely accessible as part of an innovative web-based educational and research resource. Building on experience gained through the creation of an experimental pilot database, project staff are adapting emerging standards (METS and CCO) to a custom design that presents images from the Brumfield Collection within their architectural, geographic, and chronological contexts, both as interrelated views of individual structures, and as buildings that share certain structural and stylistic features with other buildings within and beyond the Russian cultural continuum.  相似文献   

13.
《文物保护研究》2012,57(1):1-13
ABSTRACT

Shortly after a major renovation at the Royal Ontario Museum, it was noticed that the glass panels in many of the new display cases exhibited fogging or hazing on the surface, sometimes in very specific patterns. Cleaning removed the fogging temporarily, but it began to reappear within 12 months. An investigation of fogged glass panels in display cases was undertaken to understand the source of the fogging and to develop an appropriate cleaning method. This included the analysis of residues from glass panels in several galleries, and surface imaging and compositional analysis of glass panels. The fogging residues on the glass panels consist mainly of sodium salts of organic acids and inorganic anions. Sources of the sodium in the residues include air particulate matter and the glass itself. The organic acids and inorganic anions that form salts with the sodium cations likely originate from volatile organic compounds (VOCs) and particulate matter in the air. Examination of the fogging patterns on the glass panels revealed that the sodium salts grow on marks made during cleaning attempts and the manufacturing process. These cleaning and manufacturing marks contain greasy residues that encourage crystal growth. Because of the variation in surface cleanliness, panels with more cleaning and manufacturing residues appear to be heavily fogged while those with less may appear to be unfogged in the museum display cases. A cleaning protocol was tested on two of the glass panels, and was found to remove all traces of grease and fogging residue.  相似文献   

14.
《The Reference Librarian》2013,54(75-76):67-81
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15.
ABSTRACT

The Natural History Museum (NHM), London was one of the first national museums to introduce a museum-wide integrated pest management (IPM) strategy that includes the concept of risk zones (Doyle, Pinniger, and Ryder 2007). This system is based on the principle of pest prevention within a museum building, which will always have a resident population of pest insects. The loss of Dichlorvos [DDVP] resulted in an urgent need to implement a museum-wide IPM programme to protect vulnerable collections both in storage areas and on display. With such a large, diverse collection in a complex series of interconnecting buildings, it became necessary to break the programme down into sections. Thus the development and implementation of the concept of risk zones: classifying areas of the museum from high risk to low risk has proved a useful and effective method to promote staff awareness and best practice as part of a comprehensive IPM programme.  相似文献   

16.
ABSTRACT

English medieval cathedrals are a group of buildings of exceptional significance and they contain collections of equal importance. Both the historic building fabric and the artefacts are vulnerable to environmental deterioration. However, unlike buildings owned by heritage organisations, the primary purpose of cathedrals is to further the Christian mission, and the conservation of the building and collections is required to be conducted within these constraints. Increasing visitor numbers and the installation of sophisticated exhibitions makes the task of conservation all the more demanding. Next to mechanical damage, environmental factors are the greatest source of deterioration to sensitive fabric and collections. However, until recently, there has been little systematic study of English cathedral environments and the effects of different uses and control measures. Detailed studies undertaken on 20 cathedrals in the past two decades have provided an insight into their environmental performance and how they differ as a group from many other historic buildings, as well as the passive conservation measures that can be implemented within their primary function.  相似文献   

17.
ABSTRACT

Librarians are increasingly embracing project management to guide their work outside of routine library operations. Some humanities scholars, too, especially within the digital humanities community, are bringing project management techniques to bear on scholarly digital projects. We argue that librarians and their diverse collaborators can apply project management practices to a broad range of research, teaching, and learning projects with collaborators beyond the library. Two case studies illustrate this argument, one from each author's experience: creating a community biodiversity wiki for West-Central Florida and redesigning an interdisciplinary first-year seminar around creating 3-D models of historic Venetian buildings.  相似文献   

18.
ABSTRACT

Many of the sandstones at cultural heritage sites around the world are susceptible to chemical weathering, and long-term monitoring of the chemical weathering would be of great value for heritage conservation and would also provide reference data for environmental protection policies and projects. Reflectance spectroscopy is a potential tool for monitoring sandstone weathering due to its non-destructive characteristics. In this paper, we present the results of an investigation into the reflectance spectra of sandstones at the Yungang Grottoes, China, where the sandstones are variously fresh, calcite-dissolved, or argillitic-altered. We found several spectral absorptions, including those at 490, 675, 900, 1410, 1918, 2205, 2330, 2350, and 2380?nm. The absorptions at 490, 675, and 900?nm are related to hematite cement, while that at 2330?nm is associated with calcite cement. The absorptions at 1410, 2205, 2350, and 2380?nm are induced by the Al–OH vibration of kaolinite, and that at 1918?nm is related to crystal water. The calcite-dissolved sandstones have lower absorption intensities at 2330?nm than fresh sandstones, and the argillitic-altered sandstones have lower absorption intensities at 490, 675, and 900?nm than the fresh sandstones. In the 1st-derivative reflectance plots, the absorption peaks at ～1400?nm shift towards shorter wavelengths with increasing kaolinite contents. The spectral features of the fresh, calcite-dissolved, and argillitic-altered sandstones are all different, and this means they can be distinguished spectroscopically, which demonstrates the usefulness of reflectance spectroscopy for the long-term monitoring of sandstone weathering in the Yungang Grottoes.  相似文献   

19.
《文物保护研究》2013,58(3):195-208
Abstract

Pyrolysis–gas chromatography was applied to the characterization of synthetic organic pigments. On pyrolysis, azo pigments and phthalocyanine blue yield characteristic fragments. These pyrolysis products were identified, and the mechanism of decomposition was studied. In the case of paint samples, the main pyrolysis products derive from the medium, although the presence of additional peaks enables azo pigments and phthalocyanine blue to be characterized. Some examples of the analysis of artists' paints are given and the peaks are identified. The main limitation of this technique is that it is impossible to detect chemically and thermally stable pigments, or inorganic components.  相似文献   

20.
PurposeThis mixed-methods study integrates bibliometric and altmetric investigation with a qualitative method in order to assess the prevalence and societal-impact of Open-Access (OA) publications, and to reveal the considerations behind researchers' decision to publish articles in closed and open-access.Design/methodology/approachThe bibliometric-altmetric study analyzed 584 OA and closed publications published between 2014 and 2019 by 40 Israeli researchers: 20 from STEM (Science, Technology, Engineering, Math) and 20 from SSH (Social Sciences and Humanities) discipline. We used a multistage cluster sampling method to select a representative sample for the STEM disciplines group (engineering, computer science, biology, mathematics, and physics), and for the SSH disciplines group (sociology, economics, psychology, political science, and history). Required data were extracted from Scopus and Unpaywall databases, and the PlumX-platform. Among the 40 researchers who were selected for the bibliometric-altmetric study, 20 researchers agreed to be interviewed for this study.FindingsComparing bibliometrics and altmetrics for the general publications did not reveal any significant differences between OA and closed publications. These were found only when comparing OA and closed publications across disciplines. STEM-researchers published 59 % of their publications in OA, compared to just 29 % among those in SSH, and they received significantly more bibliometric and altmetric citations from SSH OA publications and from their own closed-access publications. The altmetrics findings indicate that researchers are well acquainted and active in social media. However, according to the interviewees, there is no academic contribution for sharing research findings on social-media; it is viewed as a “public-service”. Researchers' primary consideration for publishing in closed or OA was the journal impact-factor.Research limitations/implicationsOur findings contribute to the increasing body of research that addresses OA citations and societal-impact advantages. The findings suggest the need to adopt an OA-policy after a thorough assessment of the consequences for SSH disciplines.  相似文献   

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