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1.
The origin(s) and role(s) of metal soaps in paints are a worldwide concern today. These hybrid compounds, containing both fatty acid chains and metals associated with a carboxylate function, are increasingly identified in paints. As reviewed in the first part of this work, the presence of metal soaps in paints is differently interpreted in scientific publications: metal soaps are sometimes considered to play a positive role as anchor points, during paint drying processes; they can also be considered as responsible for many degradation processes (protrusions, efflorescences, darkening, etc.). Their origins are also interpreted in various ways. In some paintings (in particular from the twentieth century), they have sometimes introduced on purpose, as additives, to modify the physical properties of the painting materials. In older paintings, metal soaps are usually thought to result from an uncontrolled reaction of oil with lead-based pigments, in particular lead white, red lead, and lead tin yellow. In the second part of this work, the review of historical recipes of lead-based paint shows an important number of recipes based on controlled mixing of oil with lead driers. In the third part, the experimental reproduction of such traditional recipes using walnut oil and litharge (PbO) shows that lead soaps can be formed, both in about one hour at ～100°C, or in about one month at room temperature. It shows as well that after a few years, litharge is no longer detected in the paint medium, while different lead carbonates are. Finally, the micro-infrared spectroscopy and micro-X-ray diffraction re-analysis of protrusions from a nine-year model painting shows together with lead soaps, the presence of Pb5(CO3)3(OH)2O (‘synthetic plumbonacrite’), an unusual phase recently observed in a protrusion from a painting by Vincent Van Gogh. This work highlights (i) the multiple origins and roles of metal soaps in paints and (ii) the importance of combining the analysis of fragments from historical paintings with the analysis and reproduction of historical recipes. In particular, we show that the components detected today in historical paintings may severely differ from those originally used or prepared by the painter, complicating the assessment of the painter's intentions. More than the presence of metal soaps, the key questions to be tackled should be about their origins and (re)mobilization.  相似文献   

2.
《文物保护研究》2013,58(4):231-254
Abstract

Analyses of pigments from palettes used by J.M.W. Turner (active c.1792–c.1850) by means of microscopy, microchemical analysis, thin-layer chromatography, energy-dispersive X-ray analysis, X-ray diffraction and Fourier transform infrared spectroscopy are given. The occurrence of pigments in Turner's dated oil paintings and watercolours is also given, arranged by five-year periods. These findings are discussed in the context of published analyses of pigments from the first half of the nineteenth century. Turner used cobalt blue, emerald green, viridian, orange vermilion, barium chromate, chrome yellow, chrome orange and chrome scarlet within a few years of their known dates of discovery. It has become clear that Turner was using, or at least experimenting with, practically all the pigments known to be available at that time. In a few cases, in the light of these results, ideas on the availability of pigments to English artists have been revised backwards to the first known date of manufacture. Turner also possessed and used a wide range of red and yellow organic pigments, but few organic greens. The dyestuff extracted from Rubia tinctorum L. madder on an aluminiumcontaining substrate can be distinguished from the same madder on different substrates by its strong pink fluorescence in both ultraviolet and green light. The other red organic pigments (a second madder, brasilwood and cochineal dyestuffs on a range of substrates containing aluminium, copper, iron, aluminium/copper and clays) show negligible fluorescence. The red organic pigments were used in oil medium as well as watercolour, the yellows only in watercolour medium.  相似文献   

3.
Lead white is widely used as a white pigment in the history of Persian painting. This paper focuses on three Persian treatises dated between the twelfth and the sixteenth century, which explained different manufacturing methods of lead white or sefidāb-i-sorb. Experimental reconstruction of each recipe to access the comprehensive meaning of the text and analytical studies with X-ray powder diffraction on products of recipes revealed white compounds other than the previously known products of hydrocerussite (Pb(OH)2?·?PbCO3) and cerussite (PbCO3) in samples. Chlorine-containing raw materials mentioned in these recipes lead to the chemical products of laurionite (Pb(OH)Cl), blixite (Pb8O5(OH)2Cl4), and phosgenite (Pb2Cl2(CO)3) in the final products. These data lead to the hypothesis of the discrepancy of the lead white pigment between Iran and Europe and a marked probability of other compounds in historic Persian lead white samples.  相似文献   

4.
Objective: To determine whether information retrieval might be enhanced by making each component of a structured abstract a separately searchable field. Design: Parallel searches on records arranged so that each abstract could either be searched in its entirety or as a collection of structured fields. Subjects: Records about cardiovascular disease downloaded from MEDLINE and tested against clinical questions derived from a concurrent survey of CD-ROM use in three health science libraries. Intervention: The investigators identified terms used to structure abstracts on MEDLINE and imported the abstracts into an Idealist database prior to searching using keywords from clinical questions. Measurements and main results: recall and precision rates are given for each question in the ‘structured’ and the ‘unstructured’ set of records. Conclusions: Use of structured, rather than unstructured, abstracts improves precision at the ex-pense of recall and places heavier demands upon the searcher’s skill in choosing the correct fields within the abstract to search. Further investigation requires more accurate simulation of MEDLINE software that utilizes features such as MeSH terms, explode, facilities and delimiters.  相似文献   

5.
A multi-analytical approach for the study of brazilwood and its lake pigments was carried out based on historically accurate reconstructions. Recipes for brazilwood lakes from the fifteenth century technical text Livro de como se fazem as cores and the Winsor & Newton nineteenth century colourman's archive were reproduced and compared. Both primary sources allowed for the successful preparation of brazilwood lake pigments with colours that vary from light pink to dark red. The main steps and ingredients for the manufacture of these pigments were common in both sources, particularly the addition of Al3+ in the form of alum, and calcium carbonate (chalk). Reconstructions revealed that the latter acts as a pH buffer and filler, controlling the pH at which the lake pigment precipitates. The main difference between the two sources is that the nineteenth century recipes give the quantities for all ingredients, the precise temperatures and time, and achieved higher relative pigment yields (75% versus 45%). Full chemical characterisation of the reconstructions provided detailed information on the individual steps in the pigment manufacture and revealed that the presence of calcium sulphate dihydrate (gypsum) in the final pigment was a result of its formation in situ. Infrared, reflectance, and fluorescence spectroscopy proved to be essential and complementary techniques: while infrared was used to characterise additives and binders, reflectance and fluorescence data were fundamental for identifying the chromophore. The pigments and paints produced can now be used as standards for the identification and investigation of brazilwood lake pigments found in artworks.  相似文献   

6.
Pigments on a figurative wall painting in Poudeh village, central Iran, were analysed by micro X-ray fluorescence spectrometry, micro Raman spectroscopy, scanning electron microscopy coupled with energy dispersive X-ray spectrometry, micro Fourier transform infrared spectroscopy, X-ray diffractometry, and polarised light microscopy. Red lead, ultramarine blue, chrome yellow, brass powder, white huntite, and lammerite (Cu3(AsO4)2) were identified as red, blue, yellow, golden, white, and green pigments, respectively, while gypsum and barite were used as extender. In addition, glushinskite (MgC2O4·2H2O) was identified as a deterioration product of white huntite. Moreover, several analytical studies suggested that lammerite was a degradation product of emerald green (Cu(CH3COO)2·3Cu(AsO2)2) originally used as green pigment in the painting. The formation of lammerite is suggested to be due to the migration of arsenic throughout the paint layer. Based on the pigments identified, the wall painting is dated from the mid-nineteenth century to the mid-twentieth century.  相似文献   

7.
This article examines the significance, in the lives of those who experienced out-of-home care as children, of the archived records of their institutionalisation. The affective ramifications of accessing the records as adults are discussed, with especial focus on the records’ capacity to revive past suffering. Drawing on the work of Bruner (Crit Inq Autumn 1–21,1991, Consumption and everyday life, Sage, London, 1997) and MacIntyre (After virtue: a study in moral theory, University of Notre Dame Press, Notre Dame, 1981), a ‘narrative’ model of the self is utilised to account for the negative effect of systemic flaws in the records’ original composition. Such flaws, it is argued, have the potential to disrupt the individual’s sense of self. Both the authors, who experienced out-of-home care as children, present their own experiences of accessing the records, as case studies. The records’ manifold inaccuracies and inadequacies are interpreted in the light of prevailing welfare practices, in particular a highly damaging judgemental paradigm of gendered and moralistic assumptions of the inferior character of those in care. The authors conclude by arguing that research into the archives should involve the direct participation, as ‘insider researchers’, of those who experienced the matters contained in the records. Such participation is essential if the process of revealing and interpreting the archives is to maintain the dignity of the records’ subject individuals, and ensure the integrity of the research.  相似文献   

8.
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   

9.
《文物保护研究》2013,58(3):134-142
Abstract

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

10.
《文物保护研究》2013,58(4):239-258
Abstract

Study by X-ray microanalysis of 155 coloured grounds from French paintings of the seventeenth and eighteenth centuries allowed us to establish the nature of their constituents. The colour was introduced by three varieties of pigment, brown earths, ochres and iron oxides which were used in combination with calcium carbonate, lead white and minium. This confirms the recipes mentioned in the old treatises. The presence of barium sulphate, unexpected in this period, is connected with the nature of the coloured pigments and the place of execution of the works.  相似文献   

11.
There is a need for systemic improvement in the management of care records in Australia. This has been highlighted by government inquiries, media coverage and research literature relating to the significance of records for those who experience out-of-home care. The Who Am I? project – an interdisciplinary collaboration between historians, social workers and archivists – sought to address this concern and support positive change in 12 participating community service organisations (CSOs) in Victoria. To provide a framework for practice improvement, research archivists on the Who Am I? team designed the Self-Assessment Tool for Archives. Based on an action research methodology and influenced by the Records Continuum, this was an ‘educative intervention’ for the CSOs, as well as the participating archivists.  相似文献   

12.
James Lowry is the Deputy Director of the International Records Management Trust (IRMT). He was the lead researcher on the Aligning Records Management with ICT/e-Government and Freedom of Information in East Africa project, conducted by the IRMT from 2009 to 2011, with funding from the International Development Research Centre.

Freedom of Information (FOI) regimes can only be effective if government records are managed well. This article sets out the findings of research conducted in Kenya, Uganda and Tanzania to establish the level of alignment between those governments’ FOI aspirations and their records management readiness for FOI. The article sets out a high-level regulatory framework for the effective management of government records in the ICT/e-government and FOI environments to highlight areas that could be addressed, in order to prepare for FOI in the three countries.  相似文献   

13.
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14.
Kate Newbold 《Media History》2013,19(2):208-223
This essay explores the diverse field of audio records manufactured as tie-ins to popular American radio programs of the postwar period. Little has been written on such products as meaningful artifacts of consumption during any phase in broadcasting history. Yet radio records proved especially meaningful to customers in the 1940s and 1950s, as they offered a highly convenient way to upend rigid transmission schedules and program ephemerality. Here, I focus on spoken word radio albums that promised listeners important broadcast knowledge stored for ‘posterity’ on disk. Phonograph companies like Columbia banked on consumer interest in replay of these programs to sell radio records as technologies of permanence and documents with unparalleled historical and cultural value. I analyze program-to-record case studies like You Are There (1949) and The Quick and the Dead (1951) to illustrate how producers lay claim to historical authenticity via capturing, recording, or releasing transient moments on records.  相似文献   

15.
ABSTRACT

In Thailand, older individuals or ‘Phu Yai’ are people with higher social status and power as compared to younger people or ‘Phu Noi’ (Komolsevin &; Knutson, 2010). In the realm of education, teachers are considered Phu Yai while students are considered Phu Noi. This concept reinforces Hofstede’s (1991) major finding on Thailand being categorized as a high power-distance culture. The current study examines students’ perspective of the effect of student–teacher Facebook interactions on intercultural communication concepts such as power distance and submission to authority within the Thai student–teacher relationship. Questionnaires were administered to 353 students (N?=?353) at a large international university in Thailand. The study found that social media use between Thai students and teachers influence how students view the face-to-face power dynamics between them and their teachers. Specifically, the more students and teachers interact on Facebook, the lower students perceive the power distance between them and their teachers.  相似文献   

16.
The 2004 Truth and Reconciliation Commission (TRC) that investigated human rights abuses in Morocco under King Hassan II cited the ‘deplorable state of national archives’ as a major obstacle to its work. In 2013, in accordance with the findings of the TRC, the National Archives of Morocco opened with a colonial fonds, primarily holding records from the period of French colonisation (1912–56). This article seeks to understand the late establishment of a national archives, positing that part of the delay was caused by the focus of Moroccan nationalists on the location of indigenous records and their rejection of colonial archives and historiography.  相似文献   

17.
《文物保护研究》2013,58(4):149-154
Abstract

The small areas of white metallic pigment seen on the south wall of J. M. Whistler's ‘Peacock Room’ in the Freer Gallery of Art are platinum; this has been used, with a yellow-brown ground, to overpaint a preceding layer of silver which, in one place only, is over a preceding layer of gold. The yellow metallic pigment is confirmed as gold and the blue colour of the south wall and elsewhere is based on Prussian blue. On a separate wood panel a green was tentatively identified as copper resinate, and iron-oxide-based pigments appear to be present. In all areas investigated a white, used as a ground and in admixture, was essentially lead white and calcium carbonate. The significance of these results is discussed briefly.  相似文献   

18.
In recent years there has been growing interest in the discipline of computing in relation to cultural heritage, parallel with developments in greater user participation in archives and advances in documentation work. These trends are reflected in the case of a documentation project of an old Chinese cemetery in Singapore, Bukit Brown Cemetery. This case was characterised by tensions among the ‘wild’ array of emerging individual participants and archivists that took the momentum away from both more formal NGOs and government institutions in documenting, archiving and raising awareness of the heritage of the site when part of it was announced to be set aside for a new highway. The case presents a compelling need for participatory archives, facilitated by computing interventions encouraging public engagement and visits to the site. Being actively involved in the documentation process, the authors reflect on how conceptual frameworks of records may assist in designing new media innovations and informing the ways by which a cemetery may be documented. Through these reflections, the authors argue for the active participation of archivists and records professionals in documentation work, and demonstrate how, in the creation and keeping of records, they shape the collective imagination of the public and other stakeholders in heritage sites.  相似文献   

19.
In 2010, in response to the Australian Government’s November 2009 apology to Forgotten Australians and former child migrants, a scoping study was undertaken by the Department of Families, Housing, Community Services and Indigenous Affairs (FaHCSIA) to assess the options for a national ‘Find and Connect’ service to allow people to locate and access relevant records and have recourse to support services. The scoping study noted that Pathways, a web-based public knowledge space and a product of the Victorian ‘Who Am I?’ research project, was a community-based information resource without equal in the out-of-home care sector in Australia or indeed internationally. The scoping team made the observation that Pathways, due to its quality of content and coherent structure, appeared to be based on a set of principles and wondered what they were. In response the research team set about articulating the principles that underpinned their approach to archival documentation and the use of digital technologies – principles that had emerged through more than two decades of public domain, archive-focussed projects. This paper presents those ten principles and discusses them within the context of Pathways and the ‘Who Am I?’ project. The principles played a key role in FaCHSIA adopting Pathways as the model for the national Find and Connect database and web resource, launched on 15 November 2011. The principles underpin community knowledge building in the fourth or pluralised dimension of the Records Continuum. The paper ultimately argues that all stakeholders (all people and organisations connected with records) should have the ability to contribute to the utilisation of those records through the improvement of documentation and that some archival systems do have a duty of care to ensure they can inter-operate with community-generated knowledge.  相似文献   

20.
The role of recordkeeping in our personal and professional lives is rarely perceived as a topic of mainstream interest outside the world of professional records managers and archivists. While corporate records management has been written about throughout the recordkeeping literature, there has traditionally been less focus on what McKemmish describes as the role of ‘personal recordkeeping cultures’. Yet personal recordkeeping can play a role in creating a sense of belonging, especially for children and families. For example, within the field of Australian early childhood education, one of the key policy documents replicates a similar theme with the aptly titled ‘Early Years Learning Framework – Belonging, Being & Becoming’. By reflecting on her own personal recordkeeping story and that of her family, the author aims to explore the purpose of recordkeeping awareness and the role this plays in the wider profession. This article will draw upon relevant recordkeeping theory as well as some key early childhood education literature to introduce how ‘recordkeeping awareness’ could be reconceptualised as ‘recordkeeping literacy’. She will also explore what impact a reconceptualised understanding of continuum-based ‘recordkeeping literacy’ may have upon evolving recordkeeping theory and practice.  相似文献   

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