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• Proof of the effectiveness of gamma radiation processing for conservation purposes of biodeteriorated cultural heritage artefacts. • Gamma radiation treatment at absorbed doses common for cultural heritage conservation (up to 8 kGy). • Tests were performed at different dose and dose rate values on old books and new paper samples. • Effects of gamma irradiation parameters (absorbed dose and dose rate) on papers of different composition and conservation state. • Secondary effects evaluation by different experimental techniques (Micro-Raman, infrared spectroscopy, viscosimetric and colorimetric analysis). Ionizing radiations, commonly applied as diagnostic tools in Cultural Heritage (CH) field, are also proving effective for eliminating biodeteriogens (insects, fungi, bacteria and molds) responsible for the degradation of CH artifacts and often harmful for restorers, archivists and librarians. The use of ionizing radiations, such as gamma rays, for CH treatments is spreading in many countries. However, some CH operators remain resistant due to insufficient knowledge about the potential physico-chemical modifications (secondary effects) induced by radiation. This work aims to investigate and compare the effects of irradiation parameters (such as absorbed dose and dose rate) on old paper samples and new pure-cellulose paper, chosen as a reference model material. Absorbed doses up to 8 kGy have been used, as these values are commonly agreed upon for the preservation treatment of CH artifacts and are generally effective for biodeteriogen s removal. Optimizing irradiation conditions helps to minimize secondary effects (such as oxidation, depolymerization or color changes), thereby increasing the reliability of the process and boosting confidence among CH operators. The secondary effects were analyzed using various physico-chemical characterizations (Fourier Transform Infrared spectroscopy, Raman microscopy, viscosimetric and colorimetric analysis) on old and new paper samples. The results indicate varying behaviors, correlated with paper composition, sample age and irradiation parameters, towards gamma radiation. This groundbreaking study not only confirms the efficacy of gamma irradiation treatments but also provides essential data that will aid in the development of optimized best practice protocols and guidelines for non-destructive and minimally destructive methods applied to real case studies and treatments. [Display omitted] [ABSTRACT FROM AUTHOR]

• Gelatine and rosin-sized rag papers, rosin-sized chemical pulp and copy papers were identified. • The overall condition of the collection is "good", slightly damaged but stable. • Ferrous ions identified in 74 % of the manuscript inks but corrosion is not severe. • Papers from after 1840 exhibit lower pH and lower mechanical resistance. • Aqueous treatments should be avoided: manuscript inks of all periods are soluble in 0 % and 25 % alcohol. The Norwegian Sea Trade Archive (NST Archive) from the University of Bergen Library, Norway, is part of the UNESCO documentary heritage and contains unique documentation of the activity of companies that traded in stock fish in Norway and Europe (16th-20th century). The archive consists primarily of bound paper manuscripts written mostly in brown ink. We have surveyed this collection using a multi-analytical approach focused on the material characterization and condition of the paper carrier and inks. Our main aim was to support decision-making on establishing storage conditions, digitisation priorities, and type and extent of conservation treatments necessary to make the collection accessible. After a first visual examination to detect and quantify damages, for the paper support analysis we measured surface pH, paper thickness and water absorbency. Additionally, on a quarter of all tested materials, we performed a SurveNIR analysis, providing information regarding paper pulp type, lignin, protein and rosin content, degree of polymerization, and mechanical properties. The archival material was grouped into three periods characterising the three milestones in paper production: handmade gelatine-sized rag papers, machine-made rag papers with gelatine and rosin sizing, and papers made from processed wood pulp. Regarding the manuscripts' inks, we used iron and copper tests to determine the presence of Fe2, Cu2+ and Cu+ions, respectively. For the visual characterization and condition rating of the inks, we used the protocols described by the Netherlands Institute for Cultural Heritage. The variety of ink colours and thickness of the inked lines encountered in each document was noted down. Thus specific tendencies present in each historical period became apparent. Results of the solubility of ink in water and alcohol significantly narrowed treatment options. General tendencies of paper and ink degradation based on differences in papermaking were observed. Surface pH measurement, SurveNIR pH, rosin and protein concentration data showed that most rag papers were of poor to fair quality (pH ≤ 6.0 and low protein content (< 5 %)). Rosin-sized papers dated after 1840 had a lower pH (from 3.3 ± 0.2 to 5.0 ± 0.2) compared to gelatine-sized ones. Based on the obtained results, the overall condition of all the papers is good – slightly damaged but stable. The inks are not severely corroded, and there is no loss of text, although 20 % of the collection does show signs of iron-gall ink (IGI) corrosion. A limited number of documents, mostly before 1800, would require local antioxidative treatment. Due to the low pH of all the papers and the detection of ink corrosion, the collection should be stored in a cool environment, with low relative humidity. After the survey, digitisation priorities were also established. [Display omitted] [ABSTRACT FROM AUTHOR]

The scroll paintings for ancestor trees have been used to inherit the spirit of ancestor worship as a historical record of family development since the late Ming Dynasty in China. A severely degraded scroll painting of an ancestor tree (made of cotton textiles) needs intervention and conservation treatment to mitigate further deterioration. On the basis of the previously reported characterization results for the painting, in this paper, a suspension that is composed of 0.6% cellulose nanofibril (CNF) and nanosized 0.15% MgO in aqueous solvent (denoted as the CNF-MgO susairpension) was prepared. Conventional characterization methods were used to assess the properties of model samples before and after treatment with the CNF-MgO suspension, as well as before and after degradation under two sets of conditions. The results show that the treated model samples are slightly alkaline, given the deposit of alkaline particles, and demonstrate good mechanical properties before and after degradation due to the increase in fiber-to-fiber bond and mitigation of acid-catalyzed hydrolysis. In spite of the non-transparency of CNF and MgO nanoparticles, they have little impact on the optical properties of textiles, as verified by transmittance data and the determination of color changes. This suspension was then used to reinforce and restore the scroll painting in a practical conservation process. The application of CNF and MgO nanoparticles on textile objects investigated in this study would expand our understanding of the conservation of such objects, especially for those that have already become acidic and degraded. [ABSTRACT FROM AUTHOR]

This paper presents a preliminary conservation treatment of four pottery fragments excavated at Leptis, Libya manufactured in varied shapes, sizes, and colours. Studied objects were unearthed as sherds from two different conditions. Determination of the deterioration rates and caused factors of the pottery objects was significant to take the correct decision for conservation treatment. Results demonstrate that marine environment was more deteriorate than sandy soil. This work aims to characterize the chemical structure of pottery objects in the original environment using functional analyses. Mechanical cleaning was the first aid and safe step of conservation procedures. Desalination treatment was used for the long-term stabilization of the excavated pottery; then, internal stresses was decreased. Immersion in distilled water was efficient for decreasing water-soluble salts as halite. Insoluble water-salts were removed mechanically and chemically using dilute hydrochloric acid. Colour and thickness of the potsherds were the clues for the classification for assembling using a PVAc/CN mixture (1:1). Completely reconstruction of the excavated sherds was undertaken for understanding the occupation of the objects, then they were preserved in the storage. After desalination and assembling, painted iron stands were prepared for displaying the treated objects. [ABSTRACT FROM AUTHOR]

Abstract The Gangjin Celadon Kiln, after its excavation in 1982, was relocated and restored in 1987 and subjected to primary conservation treatment in 2007. However, many problems such as soil disintegration and cavitation occurred in the kiln until recently. In this study, the shape changes due to the conservation treatment in 2020, which was performed to maintain the original shape of the kiln site, were recorded via three-dimensional (3D) scanning, and numerical analysis was conducted to ensure continuous monitoring and preventive conservation. From the results of this study, the locations and ranges of shape changes before and after the conservation treatment of the kiln site were identified through root-mean-square (RMS) deviation analysis and visualization, and the ranges of reinforcement and soil mulch removal were quantified through the deviations at different points. In particular, the most noticeable shape changes occurring from the conservation treatment on the kiln site with 11.2 m long and 16.7° slope were around 15 mm, and many relative changes of 40 mm or more were also observed. In addition, a reinforcement of approximately 40 mm thickness at the least and a flattening were prominently evident on the floor of the working space; the inside of the combustion chamber was visualized with a reinforcement of at least about 50 mm. Damage caused by natural or artificial factors is expected because two extensive conservation treatments were applied in 2007 and 2020 to the kiln sites. Therefore, short-term monitoring using periodic 3D scanning and time-series data comparisons is necessary for the identification of the point of shape change and the determination of major damaged areas so that a mid- to long-term monitoring plan can be established based on the findings of such observations. In addition, predictive modeling research is mandated to detect areas in the entire kiln site that exhibit a greater probability of deterioration based on the available shape change data.

Magnetic audiovisual (AV) media makes up a significant part of cultural heritage. It contains elements such as sounds, images, and other data for future access. Mould growth can impact magnetic media deterioration. Over time, mould impedes element retrieval and can even cause its total loss, resulting in the loss of our cultural heritage. Therefore, proper maintenance of magnetic media is required to ensure data retention. This paper presents the findings of an international online survey to better understand current knowledge surrounding mould-affected magnetic media. Information on magnetic media is limited, resulting in the question: what are the current experiences and practices surrounding mould on magnetic media in the cultural heritage sector? The aim of the project was to seek audiovisual conservators and film practitioners' opinions about magnetic media (full coat magnetic film, magnetic audio, and video tapes), conservation processes, and their experience with mould. An on-line survey using Qualtrics software was employed. The survey indicated that mould is present in magnetic media collections regardless of substrate but may be limited to less than a quarter of magnetic media with various dual mechanical–chemical treatments used to combat mould growth. Mould continues to impact element retrieval and thus mould treatment is an important factor in deterioration prevention to ensure data retention. [ABSTRACT FROM AUTHOR]

Abstract A thin, grey surface layer was noticed after removing the varnish of an eighteenth century Dutch oil painting, by an unknown artist titled Vision of Saint Lutgard of Tongeren. This layer masked the paint layer almost entirely, casting a greyish veil that greatly influenced the painting’s appearance, colour, and saturation. Using scanning electron microscopy coupled with elemental analysis (SEM–EDX), this layer was identified as a lead-rich salt crust. The crust was a distinct layer on top of the paint layer, closely following the topography of the layer underneath but not embedded in it. The article discusses the possible theories behind the formation of this lead-rich salt crust by characterizing the painting’s material, past treatments, and environmental history. Furthermore, the article reports the decision-making process behind the removal of the crust, focusing specifically on the ethical and technical challenges of the cleaning treatment. Tests with different cleaning agents targeting separate components of the crust to remove it and different application techniques are described. The chelating agent Ethylenediaminetetraacetic acid (EDTA) was found to be the most effective in the removal of the crust and was chosen for its removal. The pH of the EDTA cleaning solution and its application had to be modified according to the colour of the paint the crust lay upon. Visual observations and analytical assessments using optical microscopy and SEM after cleaning indicate a successful reduction of the crust resulting in a significant improvement in the painting’s appearance.

This study is aimed at investigating crystals (calcium and magnesium phosphates) formed due the interaction of an inorganic conservation treatment (diammonium hydrogen phosphate—DAP) with carbonatic (calcitic and dolomitic) stones through micro-Raman Spectroscopy. The addressed questions concern (i) the identification of magnesium and calcium phosphate minerals crystallized within dolomitic stone samples with a different degree of conservation state and treated with two different DAP solution molarities and (ii) the distinction of complex calcium phosphate mixtures (hydroxyapatite—HAP and octa calcium phosphate—OCP) crystallized within a calcarenite stone treated with DAP. A statistically relevant number of Raman spectra have been acquired in sample cross sections and curve fitting analysis has been performed for the in-depth interpretation of data. The outcomes indicate that Raman Spectroscopy is an effective alternative method for the identification of poorly crystalline calcium phosphates (not easily detectable with X-ray diffraction), even when scarcely present in mixture with magnesium phosphates. Evidence of the Raman analytical capability and high potential to distinguish HAP and OCP in calcitic stones are also presented and discussed. [ABSTRACT FROM AUTHOR]

HERIe was used to model the effect of changes to indoor climate on the risk of humidity-induced mechanical damage (cracking and plastic deformation) to wooden panels painted with stiff gesso in two Norwegian medieval stone churches: Kinn (mean relative humidity (RH, %) = 79%) on the humid west coast, and Ringsaker (mean RH = 49%) in the drier eastern part of the country. The risk involved in moving cultural heritage objects (paint on wood) between the churches and a conservation studio with more “ideal”, stable conditions was also modeled. A hypothetical reduction in RH to ~65% and, proportionally, of the climate fluctuations in Kinn, and an increase in the RH in Ringsaker to a more stable value of ~63% via conservation heating, were found to improve (Kinn) and uphold (Ringsaker) the conformity to relevant standards and significantly reduce the risk of damage, except in the scenario of moving objects from Ringsaker to a conservation studio, when the risk would increase. The use of conservation heating could save ~50% of the heating cost. The estimated risk reductions may be less relevant for objects kept in situ, where cracks in the original paint and gesso have developed historically. They may be more relevant when moving original objects away from their proofed climate into a conservation studio for treatment.

The aim of this investigation was to analyze the materials and techniques of the paintings in the 16th‐century ce St Mary's Church, to evaluate deterioration of the paintings, and to propose a suitable conservation treatment for their preservation. The material analysis of ground, pigments, binders, and plasters was undertaken using binocular microscopy, field emission scanning electron microscopy (SEM)–energy dispersive X‐ray spectroscopy, X‐ray fluorescence, Fourier transform infrared spectroscopy in reflectance (KBr) and transmittance mode (attenuated total reflection), thin‐film X‐ray diffraction, and micro‐Raman spectroscopy. Gas chromatography–mass spectrometry (GC‐MS) was used for identifying proteinaceous and lipidic materials extracted from the micro‐samples. The study generated data on two different red and green pigments used as decorative materials. The red pigments were identified as cinnabar along with traces of hematite and clay minerals, and green as malachite and the minor presence of other minerals. SEM analysis identified cotton fiber embedded in the coarse plaster layer that provided better strength to the plaster. Plant oils and proteins found as the binder in the pigment samples suggested that the painting technique was executed as tempera. Lead white and gypsum materials were used in previous restoration works. [ABSTRACT FROM AUTHOR]

A thin, grey surface layer was noticed after removing the varnish of an eighteenth century Dutch oil painting, by an unknown artist titled Vision of Saint Lutgard of Tongeren. This layer masked the paint layer almost entirely, casting a greyish veil that greatly influenced the painting's appearance, colour, and saturation. Using scanning electron microscopy coupled with elemental analysis (SEM–EDX), this layer was identified as a lead-rich salt crust. The crust was a distinct layer on top of the paint layer, closely following the topography of the layer underneath but not embedded in it. The article discusses the possible theories behind the formation of this lead-rich salt crust by characterizing the painting's material, past treatments, and environmental history. Furthermore, the article reports the decision-making process behind the removal of the crust, focusing specifically on the ethical and technical challenges of the cleaning treatment. Tests with different cleaning agents targeting separate components of the crust to remove it and different application techniques are described. The chelating agent Ethylenediaminetetraacetic acid (EDTA) was found to be the most effective in the removal of the crust and was chosen for its removal. The pH of the EDTA cleaning solution and its application had to be modified according to the colour of the paint the crust lay upon. Visual observations and analytical assessments using optical microscopy and SEM after cleaning indicate a successful reduction of the crust resulting in a significant improvement in the painting's appearance. [ABSTRACT FROM AUTHOR]

HERIe was used to model the effect of changes to indoor climate on the risk of humidity-induced mechanical damage (cracking and plastic deformation) to wooden panels painted with stiff gesso in two Norwegian medieval stone churches: Kinn (mean relative humidity (RH, %) = 79%) on the humid west coast, and Ringsaker (mean RH = 49%) in the drier eastern part of the country. The risk involved in moving cultural heritage objects (paint on wood) between the churches and a conservation studio with more "ideal", stable conditions was also modeled. A hypothetical reduction in RH to ~65% and, proportionally, of the climate fluctuations in Kinn, and an increase in the RH in Ringsaker to a more stable value of ~63% via conservation heating, were found to improve (Kinn) and uphold (Ringsaker) the conformity to relevant standards and significantly reduce the risk of damage, except in the scenario of moving objects from Ringsaker to a conservation studio, when the risk would increase. The use of conservation heating could save ~50% of the heating cost. The estimated risk reductions may be less relevant for objects kept in situ, where cracks in the original paint and gesso have developed historically. They may be more relevant when moving original objects away from their proofed climate into a conservation studio for treatment. [ABSTRACT FROM AUTHOR]

The closure of the British Library during the 2020–2021 COVID-19 pandemic allowed the conservation department to undertake a treatment review of the conservation of palm leaf manuscripts in order to make better-informed decisions about the treatment of these complex objects. As part of the review a questionnaire was posted in 2020 to the Global Conservation Forum asking about the treatment of palm leaf manuscripts by others in the field. This two-part Literature Review uses the available literature and the survey results to address the wide range of issues inherent in the practical conservation of palm leaf materials. Part 1 began with an historic overview of palm leaf manuscripts and their production, leaf preparation methods, manuscript materials and media, palm leaf manuscripts at the British Library and the common types of damage found in such manuscripts. Part 2 details historic treatments and current conservation techniques as informed by our review and survey, as well as storage, religious and ethical issues. It concludes with two decision-making flowcharts, and our practical recommendations for conservators. The authors wish to share the collated information as widely as possible and help create greater continuity and consistency in palm leaf manuscript conservation by presenting recommendations for best practice for conservators who treat these amazing objects. [ABSTRACT FROM AUTHOR]

Smalt is a blue cobalt-coloured glass pigment used in European wall paintings from the early Renaissance period that became a popular choice for artists due to its unique tone, availability, and versatility. The pigment has long been considered as stable in an alkaline environment since it was applied with lime-based techniques and generally retained its colour over time. This perceived stability has meant that aqueous-based alkaline treatments, often involving high pH values, substantial quantities of liquid, and long contact times, have been used in conservation treatments. However, studies of the kinetics of glass deterioration in the past few years have demonstrated that glass is highly reactive in contact with water and substances with both high and low pH values. Research into smalt deterioration in canvas paintings has shown that smalt is susceptible to elemental leaching and physical changes in contact with water and low pH values; however, there is little specific information about the conservation implications of these findings on the treatment of smalt in wall paintings. This experimental study explores several aspects of how aqueous-based alkaline conservation treatments affect smalt grains in lime-based wall paintings: the influence of painting technique, exposure of the pictorial layer to water before treatment, and pH values and contact times during treatment. Replicas representing three different painting techniques were created, exposed to liquid water or water vapour, and treated with three substances commonly used in conservation according to accepted practices in terms of preparation and application. Chemical and physical changes in the pigment were then analysed using scanning electron microscopy with energy dispersive X-ray spectroscopy. Results confirmed that aqueous-based alkaline substances provoke chemical changes as well as physical deterioration in smalt applied in lime-based techniques evidenced by leaching, corrosion, and cracking in the pigment grains. Crucial factors found to influence the impact of treatments on smalt included the previous exposure to humidity of the pictorial layer, the pH value of the treatment, and extended contact times. [ABSTRACT FROM AUTHOR]

Copyright of Conservar Património is the property of Associacao Profissional de Conservadores-Restauradores de Portugal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Fórum pro Konzervátory-Restaurátory is the property of Technical Museum in Brno and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The closure of the British Library during the 2020–2021 Covid-19 pandemic allowed the conservation department to undertake a treatment review of the conservation of palm leaf manuscripts in order to make better-informed decisions about the treatment of these complex objects. As part of the review a questionnaire was posted in 2020 to the Global Conservation Forum asking about the treatment of palm leaf manuscripts by others in the field. This two-part Literature Review uses the available literature and the survey results to address the wide range of issues inherent in the practical conservation of palm leaf materials. Part 1 includes an historic overview of palm leaf manuscripts and their production, leaf preparation methods, manuscript materials and media, palm leaf manuscripts at the British Library and the common types of damage found in such manuscripts. Part 2 details historic treatments and current conservation techniques as informed by our review and survey, as well as storage, religious and ethical issues, before concluding with our practical recommendations. The authors wish to share the collated information as widely as possible and help create greater continuity and consistency in palm leaf manuscript conservation by presenting our recommendations for best practice for conservators who treat these amazing objects. [ABSTRACT FROM AUTHOR]

Unexpected excavation of the Osirian statuette was inaugurated in 2021 during a conservation project at the first step in the western façade of King Djoser Pyramid which dates back to the Ptolemaic era. Varies strategies of the examination techniques, such as stereo and polarizing microscopes, and scanning electron microscopy coupled to energy dispersive X-ray spectrometry and X-ray diffraction were undertaken to characterize the chemical structure of gilt-layer, preparatory layer, and bronze alloy to evaluate their condition. This paper describes the actual condition of the statuette after excavation inside the King Djoser Pyramid, and characterization of the corrosion phases, and determines the best technique for conservation. Visual investigation revealed that the core of the bronze statuette was in good condition, but most gold with gesso was misplaced. Investigation and analyses results demonstrate that amazing technique which gilding has been accomplished as a thin layer over the white substrate from gesso. X-ray diffraction establishes that cuprite and atacamite resulting from the activation corrosion were the major minerals covering the statuette. Besides, calcite and gypsum were detected, which are to be a part of the preparatory layer. EDX results demonstrate that pure gold was likely used in the gilding layer. The gilt-bronze statuette was made of multi-layered surfaces. The solid cast was used in the crafting technique. Fixation of remaining plaster to metal was undertaken using Clucel G (4%). The figure was immediately treated via popular methods as mechanical tools and solvents. Benzotriazole inhibitor (3%) was used to cure the activation of bronze disease. The coating system was applied by using 3% paraloid B72. Finally, the statuette was preserved in the storage with the appropriate conditions.

Abstract Abstract Guard Dog II (1969–1970) by Jean Dubuffet is an artwork that shows the characteristics of the artist's l'hourloupe period (1962–1974). This study revealed the materials and manufacturing techniques used by the artist at the time through material analysis of Guard Dog II, and suggested an appropriate conservation treatment method for the work through a cleaning test. Dust, stains, discoloration, cracks, etc. were observed on the surface of the artwork and stains were particularly severe and discoloration required conservation treatment. Prior to treatment, multiple analytical approaches such as Fourier transform infrared spectroscopy, Raman spectroscopy and gas chromatography/mass spectrometer were applied to identify the materials of the paint layers and confirm the state of the conservation of the artworks. As a result, it was confirmed that polyurethane paint was used in the artwork, and the pigment used for each color was also identified. For the stable conservation treatment of the artwork, the chromaticity, glossiness and workability of the cleaning materials were evaluated, and it was found that isopropyl alcohol and nonionic surfactant were suitable for cleaning. The conservation treatment was performed based on results from the cleaning test, and the artwork was restored cleanly. Since most of the existing research on cleaning methods has been focused on painting, this study contributes to the conservation of sculptures by suggesting cleaning methods suitable for three-dimensional colored objects. Article highlights The materials and production techniques used in Jean Dubuffet, Guard Dog II were confirmed. As cleaning materials for deteriorated artworks, isopropyl alcohol and non-ionic surfactants are effective. Hydrogels are not suitable for this work due to the type and characteristics of the gels.

Copyright of Conservar Património is the property of Associacao Profissional de Conservadores-Restauradores de Portugal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

2.2 Nanoparticle Formulations and Application Procedure Nanoparticle formulations were designed and synthesised by the partners involved in the NANOforArt project and comprised calcium hydroxide or calcium carbonate nanoparticles dispersed in propan-2-ol or cyclohexane ([2]; [26], [27]; [32]). In Figure 3, the plot of elastic modulus ( I E' i ) versus RH is presented for control untreated, and nanoparticle treated samples as measured by Controlled Environment Dynamic Mechanical Analysis (DMA-RH). Similar nanoparticle formulations were also applied on leather showing the same positive effects: accelerated thermal ageing proved to induce more damage to untreated leather sample compared to CaCO SB 3 sb -treated sample and aged treated sample ([2]; [26]). Keywords: parchment; conservation treatment; alkaline nanoparticles; pH adjustment; Pergament; konservatorische Behandlung; alkalische Nanopartikel; pH-Einstellung EN parchment conservation treatment alkaline nanoparticles pH adjustment DE Pergament konservatorische Behandlung alkalische Nanopartikel pH-Einstellung 143 158 16 07/18/22 20220301 NES 220301 1 Introduction Materials and practices used in the past for the conservation treatment of parchment have been proven to lead to unwanted alterations and major changes ([19]; [10]). [Extracted from the article]

An interesting example of a bronze seated Osiris statue dated back to the Late Period (664-332 B.C), preserved in the store museum of Kom Oshim, Fayoum, EGYPT. The hollowcasting process was used in the statue manufacturing technique. A detailed characterization of the statue was carried out through USB digital microscope, metallographic examination, portable X-ray fluorescence, X-ray diffraction and scanning electron microscope with energy dispersive spectroscopy. The results revealed that statute has been made of lead bronze alloy with low tin and high lead. EDS results showed that the gold leaf contains more than 90%wt. Au content. The corrosion products identified by XRD are cuprite, malachite, azurite and atacamite. Pre-treatment, a consolidation and fixing processes were carried out by using Paraloid B72 3% in acetone to ensure that the gilding adhered firmly to the surface. Mechanical cleaning was accomplished via safe hand tools to remove corrosion products and soil encrustations and avoid losing the gold remains. BTA 3% in alcohol was applied in the areas of active corrosion, then two layers of permalac were applied. [ABSTRACT FROM AUTHOR]

This work follows a previous one dealing with the state of conservation study of the wooden part of the roman Acqualadroni rostrum soon after its finding in the seabed of Acqualadroni (Messina, Italy). The archaeological survey and recovery were particularly relevant since this artefact is one of the two rostrums, nowadays known, found together with its wooden part. Following the recovery, it was consolidated by immersion in a melamine-formaldehyde resin (Kauramin) aqueous solution for eight months at the "Centro di Restauro del Legno Bagnato" (Pisa, Italy). The present investigation is aimed to determine at microscopic scale the wood state of conservation and to highlight interactions of the consolidant with wood components, by using solid-state NMR spectroscopy ten years after the consolidation treatment. Sampling by coring was exceptionally authorized, and the wood core was divided into seven aliquots as a function of depth. 13C cross-polarization magic angle spinning (13C{1H} CP-MAS NMR) spectra and variable contact time (VCT) experiments have been carried out to determine the cellulose crystallinity index, the lignin condensation degree and the holocellulose-lignin ratio. The interactions between the resin and the wood components were highlighted by T1ρH relaxation times determination and two-dimensional 13C–1H correlation (FSLG CP HETCOR) NMR experiments. Findings revealed specific interactions between the aromatic part of the resin and the lignin, as well as a network of hydrogen bonds involving all components of the system. [ABSTRACT FROM AUTHOR]

England's East Anglian region has c.550 late-medieval screens still in their original churches, one of Northern Europe's most significant in situ collections of medieval panel painting. The churches are managed by non-specialist volunteers and are not museums. In many, congregations are shrinking and long-term sustainability will involve varying uses of the building. The buildings and their collections are at risk from, among other factors, weather, groundwater, fire, heat, moisture, light, pollutants and pests, as well as vandalism and theft. The same threats affect screens, causing flaking paint, microbiological growth, insect damage and photodegradation. A collaborative programme was forged between the Hamilton Kerr Institute, University of Cambridge, specialists in medieval panel painting conservation, and Tobit Curteis Associates, specialists in environmental deterioration in historic buildings, supported by the Church of England's Cathedral and Church Buildings Division. This project aimed to bridge the gap between the conservation of sensitive artefacts and the conservation of the buildings in which they are situated. A methodology, utilising materials analysis, environmental monitoring and building and object surveys, was devised for the assessment of the deterioration of screens and their churches to produce holistic recommendations. Through a pilot study, solutions that are passive, cost effective, innovative and sustainable are being implemented. [ABSTRACT FROM AUTHOR]

A conserved painting removed from a Neolithic collective grave in Marne, France, provided an opportunity for radiocarbon dating to place Les Ronces Hypogeum 21 (Villevenard) into the chronology of that region. Chemical analysis with direct analysis in real time (DART) mass spectrometry, Fourier transform infrared (FTIR) spectroscopy and gas chromatography-mass spectrometry (GC-MS) of samples from the painting revealed the presence of two kinds of wax (beeswax and paraffin or microcrystalline wax) that likely were added during the conservation, a drying oil like linseed oil, as well as markers of pine resin that may arise from turpentine or colophony. A new pretreatment protocol of chloroform followed by pH 8 phosphate buffer was developed, which yielded sufficient material for plasma-chemical oxidation and AMS radiocarbon dating. The radiocarbon dates place the image from Hypogeum 21 at the more recent end of the chronology that spans from the sixth to the third millennia cal BC for the Neolithic in France. [ABSTRACT FROM AUTHOR]

International heritage doctrine and the Operational Guidelines (OG) for the Implementation of the World Heritage (WH) Convention discourage the reconstruction of cultural heritage. Only 'exceptional circumstances' justify this practice, namely armed conflicts and natural disasters. The UNESCO WH Committee recently expressed its support for the reconstruction of damaged WH properties in view of such circumstances and requested the development of new guidance to address this timely issue (Decisions: 39 COM 7 and 40 COM 7). Guidelines will be prepared and provided to the Committee accordingly (Decision: 41 COM 7). We can therefore foresee revisions and additions to Paragraph 86, which is currently the only guideline in the OG, deemed 'inadequate' by the Committee. This research paper brings into focus the status of reconstruction in WH policy formulation and takes a normative position. Drawing on document analysis and the most up-to-date studies, I argue that its status should formally shift from exceptional case ruled outa priori to conservation treatment ruled in. I encourage a fruitful international exchange of ideas among a broad interdisciplinary readership to contribute to policy-making. Readers who dispute my position, no less than those who support it, may come to see reconstruction in a different light. [ABSTRACT FROM AUTHOR]

Copyright of Journal of the American Institute for Conservation is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Archaeological waterlogged elm wood was treated with methyltrimethoxysilane (MTMS) and (3-mercaptopropyl)trimethoxysilane (MPTES), respectively, and anti-shrink efficiency and sorption properties of the impregnated wood samples were determined. The applied impregnants stabilized wood dimensions efficiently enough, i.e. the obtained anti-shrink efficiency was 81 and 98% for MTMS- and MPTES-treated wood, respectively. Both alkoxysilanes can be considered as potential new consolidants. Hygroscopic properties of untreated and impregnated wood were investigated with the DVS experiments. The application of MTMS and MPTES reduced wood equilibrium moisture content (EMC) and sorption hysteresis e.g. hysteresis relative change was −83.7 and −73.7% for MTMS- and MPTES-treated wood, respectively. The EMC reduction was observed in the whole hygroscopic range and it was primary due to the monolayer capacity decrease to 50 and 30% of the value for untreated wood and observed for adsorption and desorption modes, respectively. The DVS experiments revealed chemical instability of the MTMS-wood system which was neutralized after the cyclic sorption. The possible scenarios of the interaction of both alkoxysilanes with wood structure were discussed. Highlights • Treatment with alkoxysilanes stabilizes waterlogged archaeological wood. • Wood impregnation reduces equilibrium moisture content in the whole hygroscopic range. • Application of alkoxysilanes improves wood hygroscopic properties even at high relative humidity. • Methyltrimethoxysilane-wood system requires additional stabilization after the treatment. [ABSTRACT FROM AUTHOR]

Abstract Here we demonstrate the extension of applicability of high resolution Attenuated Total Reflection Fourier transform infrared μ-mapping (ATR μ-FTIR) to the investigation of the diffusion of a conservation treatment, ammonium oxalate, within painted plasters. The method demonstrates its potentiality in situations where high lateral resolution is required and the compounds are not easily detectable with conventional analytical techniques. It was applied successfully to explore the interaction between ammonium oxalate solutions and the carbonatic matrix at the microscale. The reaction of the carbonatic aggregate particles was assessed as well as the influence of the treatment parameters on the penetration depth. High resolution ATR μ-FTIR represents a new spectroscopy imaging modality expanding the portfolio of chemically specific analytical tools. [ABSTRACT FROM AUTHOR]

The aim of this research is to establish an effective procedure of iron gall ink characterization using complementary non-destructive methods. By this, it is possible to better understand correlation of chemical composition of the inks and the state of preservation of iron gall ink manuscripts, as well as the effects of conservation treatment performed upon them. This study was undertaken on a bound 16th century manuscript comprised of different types of paper and ink from the National and University Library in Zagreb. Analytical methods used included Particle Induced X-ray Emission (PIXE) and X-ray Fluorescence (XRF). Paper fibers were identified by optical microscopy and the degradation state, as well as ink differentiation, transit metal migrations and detection of stains, with ultraviolet (UV) and infrared (IR) photography. The techniques applied on original writing materials gave important information about paper and ink composition, its preservation state and efficiency of conservation treatment performed upon them. [ABSTRACT FROM AUTHOR]

A waterlogged subfossil Scots pine wood, 12 500-years-old, was impregnated with a mixture of lactitol and trehalose as well as with polyethylene glycol (PEG) mixtures, respectively, and the sorption properties of the impregnated samples were determined. All the impregnated wood samples were freeze-dried. The sorption isotherms were parameterized with the Guggenheim-Anderson-deBoer (GAB) and Generalized D'Arcy and Watt (GDW) models. Better hygroscopic properties were found for wood impregnated with the lactitol and trehalose mixture as compared to the PEG treatments. An anomalous increase of equilibrium moisture content (EMC) was found for PEG treated wood at a high relative humidity (RH) as compared to untreated wood at RH < 80%. The lactitol and trehalose mixture significantly reduced this effect due to the decreased sorption of polymolecular water. Another positive effect of the alternative method is the ca. 50% reduction of the sorption hysteresis as compared to untreated wood. Moreover, the hysteresis was also much lower in the case of high RH as compared to PEG treated wood. The alternative treatment is also effective in terms of the dimensional stabilization of decayed wood. [ABSTRACT FROM AUTHOR]