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Double-layer renders were formulated for ensuring salt migration, ancient masonries conservation and environmental sustainability. Thus, natural hydraulic lime as binder and recycled aggregates from render wastes were selected. The properties were adjusted by adding an air-entraining agent in the inner layer and different percentages of water-repellent admixtures in the outer layer. The systems were applied on bricks and subjected to rising damp-evaporation cycles, for investigating their behaviour and properties in respect to NaCl migration. Mono-material prismatic render specimens were also studied. Water vapour permeability, capillary absorption, drying behaviour, compressive strength, mechanical resistance, conductivity and porosity of each formulation were evaluated. Good durability was observed whenever the render layers had different microstructure, either there was salts deposition within the lower layer,or if there was tefflorescences formation. If the layers had similar structure, deposition of salt at the brick-render interface occurred causing damages to the substrate.

Conservation environment with high humidity content or exposure to liquid water are directly linked to degradation of cellulosic materials, such as paper and fabrics. This research had as main objective the development of formulations based on two water-repellent products commercially available: a fluoroacrylic co-polymer and a polydimethylsiloxane. The purpose was to test their applicability to paper and textiles, both ancient and modern. Different analytical techniques have been used: FTIR-ATR spectroscopy, colorimetric analysis, observations by SEM-EDX and light microscopy, contact angle measurement and mechanical strength. Applications were carried out by spray and immersion achieving a systematization of the method and the choice of non-toxic solvents. Two of the four formulations tested were prepared with the addition also of silica nanoparticles. The results highlighted the compatibility and effectiveness of fluoroacrylic polymer with low nanosilica percentages applied by immersion.

In the last years, significant research effortsin the cultural heritage area have been conducted towards environmentalimpact reduction of biocides and to improve theireffectiveness overtime.This paper proposes an approach based on encapsulation/incorporation of zosteric sodium salt, ZS, an environment friendly biocide, in silica nanocapsules. The aim of this work is the development of a material for controlled release of bioactive species to be incorporated into coatings. Porous silica nanocapsules have been fabricated by the one-step synthesis called dynamic self-assembly (DSA) [1]

Summary This study is part of a research project dealing with the establishment of monitoring and damage prevention plans for contemporary artworks. For this purpose, some commercial paints, among the most currently used by young artists, were selected: Winton oil paint (Winsor & Newton, UK), Heavy Body acrylic paint (Liquitex, USA) and Flashe vinyl paint (Lefranc & Bourgeois, France). The paints were subjected to different treatments of accelerated ageing, the results indicating different behaviour in relation both to the type of binders and pigments present in the different formulations. In particular, it was observed that ageing produced by ozone plays an important role in the stability of the oil paints, above all in those containing organic azo pigments. Thermal ageing, as expected, influences the stability of all the commercial paints examined, with the formation of alteration products and visible changes in the paint films. Ageing produced by moisture clearly affects the synthetic polymer-based paints, particularly evident in the changes in mass. In all cases, the accelerated ageing treatments produced chromatic variations, more evidently for the oil paints containing organic pigment. Riassunto Questa ricerca s’inserisce nel tema della predisposizione di piani di monitoraggio e di prevenzione del danno su opere pittoriche contemporanee. A questo scopo sono state selezionate alcune pitture commerciali, fra le più utilizzate attualmente da giovani artisti: pitture ad olio Winton (Winsor & Newton, UK), acriliche Heavy Body (Liquitex, USA) e viniliche Flashe (Lefranc &Bourgeois, France). Le pitture sono state sottoposte a diversi trattamenti di invecchiamento accelerato e i risultati indicano comportamenti differenti in relazione sia al tipo di legante che al tipo di pigmento presente nelle diverse formulazioni. In particolare è stato osservato che l’invecchiamento prodotto dall’ozono gioca un importante ruolo nella stabilità delle pittura con legante ad olio, in particolare in quelle contenenti pigmenti organici (OY). L’invecchiamento termico, come atteso, influenza la stabilità di tutte le pitture esaminate, con formazione di prodotti di alterazione e visibili modifiche dell’aspetto. L’invecchiamento prodotto dalla umidità comporta invece evidenti effetti sulle pitture a base polimerica, rilevabili in particolare dalle variazioni di massa. L’invecchiamento accelerato produce in tutti i casi delle variazioni nelle coordinate colorimetriche, molto più marcate nei colori organici con legante lipidico. Résumé Cette recherche relève du thème de la préparation de plans de suivi et de prévention de la détérioration d’oeuvres picturales contemporaines. Des couleurs du commerce parmi les plus utilisées actuellement par les jeunes artistes ont été sélectionnées à cet effet : couleurs à l’huile Winton (Winsor & Newton, Royaume-Uni), acryliques Heavy Body (Liquitex, États-Unis) et vinyliques Flashe (Lefranc & Bourgeois, France). Les peintures ont été soumises à plusieurs traitements de vieillissement accéléré. Les résultats montrent que les couleurs se comportent de manière différente selon le type de liant et à la fois le type de pigment des différentes formulations. En particulier, il a été observé que le vieillissement par l’ozone joue un rôle important dans la stabilité des peintures à liant huileux, en particulier dans celles qui contiennent des pigments organiques (jaune). Comme attendu, le vieillissement thermique influence la stabilité de toutes les peintures examinées, avec la formation de produits d’altération, l’aspect étant visiblement modifié. Quant au vieillissement par l’humidité, ses effets sont évidents sur les peintures à base de polymères, et détectables surtout dans les variations de masse. Dans tous les cas, le vieillissement accéléré provoque des variations des coordonnées colorimétriques, beaucoup plus évidentes dans les gammes des jaunes et des verts à liant gras. Zusammenfassung Diese Forschungsarbeit fällt in den Bereich der Bereitstellung von Plänen zur Überwachung und zur Verhinderung von Schäden an zeitgenössischen Gemälden. Zu diesem Zweck wurden einige der handelsüblichen Farben gewählt, die derzeit von jungen Künstlern am häufigsten verwendet werden: Ölfarben Winton (Winsor & Newton, UK), Acrylfarben Heavy Body (Liquitex, USA) und Vinylfarben Flashe (Lefranc & Bourgeois, Frankreich). Die Farben wurden verschiedenen Behandlungen zur Beschleunigung der Alterung unterzogen und die Ergebnisse weisen sowohl in Bezug auf die Art der Bindemittel als auch auf die Art der Pigmente, die in den verschiedenen Formeln enthalten sind, unterschiedliches Verhalten auf. Insbesondere wurde beobachtet, dass die durch Ozon verursachte Alterung für die Stabilität von Ölfarben eine bedeutende Rolle spielt, besonders wenn sie organische Pigmente (organisches Gelbpigment) enthalten. Die thermische Alterung beeinflusst wie erwartet die Stabilität aller untersuchten Farben, wobei sich Zersetzungserscheinungen einstellen und sich das Aussehen sichtbar verändert. Die durch Feuchtigkeit bedingte Alterung zeigt sich dagegen sehr deutlich bei Polymerfarben und ist speziell an der Veränderung der Masse zu erkennen. Die beschleunigte Alterung führt in allen Fällen zu Veränderungen der Farbkoordinaten, die bei gelben und grünen Farben, die mit fetthaltigen Bindemitteln hergestellt werden, besonders ausgeprägt sind. Resumen Este trabajo de investigación trata el tema de la realización de programas de monitorización y prevención de daños en obras pictóricas contemporáneas. Para tal fin, se han seleccionado algunas de las pinturas comerciales más utilizadas actualmente por parte de jóvenes artistas: pinturas al óleo Winton (Winsor & Newton, Reino Unido), acrílicas Heavy Body (Liquitex, EE. UU.) y vinílicas Flashe (Lefranc & Bourgeois, Francia). Las pinturas han sido sometidas a varios tratamientos de envejecimiento acelerado y los resultados muestran comportamientos diferentes tanto según el tipo de aglutinante como de pigmento empleados en las distintas fórmulas. En especial, se aprecia que el envejecimiento provocado por el ozono juega un papel importante para la estabilidad de las pinturas con aglutinante al óleo, en particular para las que contienen pigmentos orgánicos (amarillo). El envejecimiento térmico, tal y como se esperaba, influye sobre la estabilidad de todas las pinturas examinadas, dando lugar a la formación de productos de alteración y cambios visibles en el aspecto. Por su parte, el envejecimiento producido por la humedad conlleva claros efectos en las pinturas a base de polímeros, apreciables, en particular, a causa de la variación de masa. El envejecimiento acelerado produce, en todos los casos, variaciones de las coordenadas colorimétricas, las cuales son mucho más marcadas en los colores amarillos y verdes realizados con aglutinante lipídico. 简述 这份研究的课题是现代绘画作品损坏的监控和预防工作计划。针对这一目标，共选取 几种市场流通的颜料，其中包含了年轻艺术家常用的几款：Winton油性颜料（英国 Winsor & Newton），Heavy Body丙烯颜料（美国Liquitex）和Flashe醋酸乙烯染料（ 法国Lefranc & Bourgeois）。这些颜料经过不同加速老化处理后，结论显示不同粘合 剂和不同色料在各配方中的选择和比例，产生了不同的实验结果。值得注意的是，使 用油性粘合剂的颜料，尤其在含有有机颜料（OY）的样本中，臭氧对其稳定性起到重 要作用。正如预想，热性老化对全部颜料作品的稳定性均造成影响，损坏伴随着腐蚀 物的产生和外观的可视改变。而湿度对绘画作品的腐蚀，在使用聚合物材料的作品中 尤为明显，可检测到多种类大范围变化。加速老化在所有样本上，均造成色彩变化， 其中由类脂性粘合剂制成的黄色和绿色，变色现象尤为明显。 Резюме Настоящее исследование относится к составлению программ мониторинга состояния и предотвращения повреждений современных работ живописи. В этих целях нами были отобраны образцы имеющихся в продаже красок, которые молодые художники наиболее часто используют в настоящее время. Это - масляные краски Winton (производства Winsor & Newton, Великобритания), акриловые краски Heavy Body (Liquitex, США) и виниловые краски Flashe (Lefranc & Bourgeois, Франция). Краски подвергались различным процессам ускоренного старения. Полученные результаты меняются в зависимости как от типа связующего вещества, так и от типа пигмента, присутствующего в различных составах. В частности, было отмечено, что озонное старение играет важную роль в стабильности красок с масляным связующим веществом, особенно красок с органическими пигментами. Как и предполагалось, тепловое старение влияет на стабильность всех исследуемых красок, вызывая образование продуктов порчи и заметные изменения внешнего вида. На краски на полимерной основе влажностное старение оказывает значительное воздействие, выражающееся главным образом в изменении массы. В любом случае ускоренное старение вызывает изменения координат цветности, которые являются особенно заметными в желтых и зеленых красках, произведенных с применением липидного связующего вещества., Conservation Science in Cultural Heritage, Vol 14 (2014)

Woven cotton fabrics were treated with a polyurethane modified aminosilicone fluid commonly used as a fabric softener. The aminoethylaminopropyl polydimethylsiloxane was modified with an aqueous dispersion of polycarbonate diol polyurethane using isopropyl alcohol as co-solvent resulting in stable micro-emulsions with an average droplet size of 1.5 μm. Polycarbonate polyurethane was chosen due to its good hydrolytic stability and low water absorption levels. Fabrics were treated either by immersion in emulsions or by spray coating. Treated fabrics had static water contact angles exceeding 143o with droplet shedding angles of less than 50o depending on the droplet volume. Treated textiles were breathable with vapor permeability levels of 5.6 mg (m day Pa)−1 that was similar to untreated fabrics. Good droplet shedding action was achieved based on the inherent fiber roughness. Accelerated ageing tests corresponding to 5 years using CIEL*a*b standards (7.5 × 106 lx∙hours exposure) indicated that no ageing occurred, with the overall color parameter of ΔE < 2.0 indicating invisible color changes to the naked eye. This sustainable approach can be easily scaled and may be a valuable treatment alternative for delicate fabrics commonly encountered in Heritage preservation; but also for many other cotton-based textiles.

International audience; A record of Pb isotopic compositions and Pb and Ba concentrations are presented for the EPICA Dome C ice core covering the past 220 ky, indicating the characteristics of dust and volcanic Pb deposition in central East Antarctica. Lead isotopic compositions are also reported in a suite of soil and loess samples from the Southern Hemisphere (Australia, Southern Africa, Southern South America, New Zealand, Antarctica) in order to evaluate the provenance of dust present in Antarctic ice. Lead isotopic compositions in Dome C ice support the contention that Southern South America was an important source of dust in Antarctica during the last two glacial maxima, and furthermore suggest occasional dust contributions from local Antarctic sources. The isotopic signature of Pb in Antarctic ice is altered by the presence of volcanic Pb, inhibiting the evaluation of glacial–interglacial changes in dust sources and the evaluation of Australia as a source of dust to Antarctica. Consequently, an accurate evaluation of the predominant source(s) of Antarctic dust can only be obtained from glacial maxima, when dust-Pb concentrations were greatest. These data confirm that volcanic Pb is present throughout Antarctica and is emitted in a physical phase that is free from Ba, while dust Pb is transported within a matrix containing Ba and other crustal elements.