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Nel mese di settembre 2020 veniva presentato nel duomo di Tarquinia il volume avente ad oggetto gli affreschi del Pastura nella cappella Vitelleschi ora nel coro della chiesa, oggetto di un impegnativo restauro allora da poco ultimato. L'intervento era stato l'occasione per ammirare da vicino il ciclo pittorico e comprendere la tecnica e lo stile di questo artista, cosí importante per la storia dell'arte del Lazio e dell'Umbria meridionale, che lavorò a fianco di artisti celeberrimi come Perugino e Pinturicchio. Le pitture erano pervenute ai nostri giorni danneggiate dal calore prodottosi da un incendio a metà Seicento, che ne aveva sciolto le applicazioni di cera dorate. Gli spunti di interesse del cantiere erano stati tali da aver raccolto la preziosa collaborazione dell'infrastruttura IPERION_CH (Integrated Project for the European Research Infrastructure on Culture Heritage) ed il coinvolgimento del CNR, del MOLAB, del Dipartimento di Chimica e Chimica Industriale dell'Università di Pisa, del Dipartimento di Chimica dell'Università di Bologna. [...] In questo volume vengono resi noti i dati degli studi e delle indagini diagnostiche relativi a quel restauro, Per una serie di positive circostanze l'attività di tutela della Soprintendenza è riuscita in questi ultimi anni a dedicarsi a più opere del Pastura nella provincia di Viterbo. Sono stati compiuti restauri finanziati dalle Diocesi proprietarie dei beni (Civitavecchia, Civita Castellana e Viterbo) ed altri realizzati con il contributo di privati [...] Parallelamente la Soprintendenza di Roma ha avviato il cantiere di restauro della cappella Ponziani in Santa Cecilia in Trastevere, e grazie alla proficua collaborazione tra i funzionari delle due Soprintendenze, attraverso lo scambio di dati ed opinioni, anche di intervento, i risultati di quel restauro sono confluiti in questo volume.'

The invention of paper has undoubtedly been an important step for human civilization allowing large amount of scientific, musical, artistic, historical knowledge to be handed down over the centuries. However, paper as many other materials suffers from degradation over time. Investigations made in 2008 by J. Wouters on European libraries showed that on average 30% of paper objects are in poor condition of conservation while another 30% will reach these conditions at the end of this century. The degradation of paper is a complex phenomenon with different causes among which the more common ones include biological, physical and chemical processes. In addition, inadequate storage and careless handling can be a typical risk factor in accelerating further degradation processes. Consequently, the protection and preservation of paper-based artworks poses a serious problem for numerous libraries, archives, and museums. This is the reason why in recent years many studies have been focused on the monitoring of paper weathering by applying advanced analytical techniques and on the development of appropriate and long-term resistance treatments to protect these valuable documents.

L'opera presenta i risultati della ricerca svolta su alcune opere di Giuseppe Capogrossi, pittore romano tra i primi a rivoluzionare il linguaggio artistico italiano del secondo dopoguerra, conservate alla Galleria Nazionale d'Arte Moderna e Contemporanea di Roma. La ricerca è nata dalla collaborazione tra l'Università degli Studi di Urbino Carlo Bo e la Galleria Nazionale d'Arte Moderna e Contemporanea di Roma, sotto l'egida della Fondazione Archivio Capogrossi. Le tre tele scelte - Superficie 207 del 1957, Superficie 538 del 1961 e Superficie 553 del 1965 - appartenenti al periodo "segnico", sono state oggetto di una mirata e approfondita campagna di indagini scientifiche effettuata in collaborazione con numerose istituzioni all'avanguardia nel campo della ricerca e del restauro sui beni culturali e in parte finanziata dall'infrastruttura E-RIHS (European Research Infrastructure for Heritage Science) con il supporto economico del Ministero dell'Istruzione, dell'Università e della Ricerca.

L'opera presenta i risultati della ricerca svolta su alcune opere di Giuseppe Capogrossi, pittore romano tra i primi a rivoluzionare il linguaggio artistico italiano del secondo dopoguerra, conservate alla Galleria Nazionale d'Arte Moderna e Contemporanea di Roma. La ricerca è nata dalla collaborazione tra l'Università degli Studi di Urbino Carlo Bo e la Galleria Nazionale d'Arte Moderna e Contemporanea di Roma, sotto l'egida della Fondazione Archivio Capogrossi. Le tre tele scelte - Superficie 207 del 1957, Superficie 538 del 1961 e Superficie 553 del 1965 - appartenenti al periodo "segnico", sono state oggetto di una mirata e approfondita campagna di indagini scientifiche effettuata in collaborazione con numerose istituzioni all'avanguardia nel campo della ricerca e del restauro sui beni culturali e in parte finanziata dall'infrastruttura E-RIHS (European Research Infrastructure for Heritage Science) con il supporto economico del Ministero dell'Istruzione, dell'Università e della Ricerca.

In the framework of the ADAMO Project (Analysis Technologies, DiAgnostics and Monitoring for the Conservation and Restoration of Cultural Heritage), a measurement campaign was carried out by different diagnostic techniques for assessing the content and distribution of moisture in the lower part of the apse of the church of San Nicola in Carcere in Rome.

Nell'ambito del Progetto ADAMO (Tecnologie di Analisi, DiAgnostica e MOnitoraggio per la conservazione e il restauro di beni culturali), si è svolta una campagna di misure con diverse tecniche diagnostiche per la valutazione del contenuto e della distribuzione dell'umidità nella parte bassa dell'abside della chiesa di San Nicola in Carcere a Roma. L'approccio multidisciplinare è stato condotto con la termografia ad infrarossi, Risonanza Magnetica portatile, Indagini in situ mediante immagini acustiche, Indagini con prove soniche e ultrasoniche sulla muratura , termografia sonica e diagnostica remota mediante fluorescenza indotta da laser su porzioni dei muri absidali .

In this study a multi-analytical approach has been performed to characterise the constitutive materials of an ancient painted barkcloth or Tapa. Originating from Wallis Island, Polynesia, this cloth likely served utilitarian or ceremonial purposes and is part of the Felice Junck collection at the Pigorini, Muciv museum of Rome. During a recent conservation project, some micro-samples were taken from the support, brown and black painted areas and were investigated using the complementarity of SEM-EDX, FT-IR, Raman/SERS and solid-state C NMR and H HR-MAS spectroscopy. The combination of these techniques allowed the chemical characterization of the constitutive materials, from distinguishing the lignin and cellulose content of the support to the use of organic materials including condensed tannins (catechin, anthocyanidins, alkaloids), phlobaphene and vegetal anthraquinone based Morinda genus dyes for the decorations. A primary focus was placed on an understanding of its state of conservation where data of alteration products collected, namely metal carboxylates and oxalates can serve to formulate apt restoration efforts for this specific artefact.

The aim of this work is the assessment of the possibility to produce geopolymeric materials for the specific use in the field of consolidation of stone materials or as restoration mortars, through mechanochemical activation of two solid precursors, quartz and kaolin. These starting materials were modified by grinding at different times and then the degree of reactivity of the obtained products was verified by studying the changes induced by the mechanical treatment on the crystalline structure and by determining the specific surface. Moreover the solubility and kind of alkaline solutions classically used for the production of geopolymeric materials (NaOH and KOH) was investigated together with other aqueous solutions at variable pH. The mechano-chemical activation process can achieve the result to reduce the use of alkaline solutions as activators of the starting raw materials in the production of consolidating solution for monument stone materials and to utilise natural materials in the production of restoration mortars compatible with the substrates to be restored.

An oxidative reaction of cellulose with sodium metaperiodate was performed. The oxidised groups were decomposed by treatment with UV light into free macroradicals. In the presence of acrylic monomers, in the vapour phase, these reactive sites become the starting points for the graft copolymerisation of the cellulose substrate. In this study we examined the graft yield as a function of the polymerisation time and the oxidation degree of cellulose. The grafted polymer was characterised using several analytical techniques, DSC analysis, GPC analysis, viscosity, FTIR and 13C CP-MAS. Information on the morphology of grafted chains with respect to the bulk cellulose was obtained, measuring the dynamic parameters in a careful 13C CPMAS NMR study. All proposed chemical reactions, if properly conducted, do not affect the crystallinity of cellulose and introduce only a very modest amount of oligomers, therefore they seem suitable for the consolidation and protection of precious cellulose based materials,which are of storical interest.

Multifarious applications of NMR (high-resolution NMR in liquid-state and in semi-solid matrices, low-field NMR relaxometry, and NMR-imaging) in the analysis of food components and entire food samples are described using examples of different food matrices and different problems related to food safety, traceability, geographical and botanical origin, farming methods, food processing, maturation and ageing, etc. Althoug NMR has not yet been recognized as an official methodology for the food control the numerous applications of NMR reported in the literature show the potenziality of this methodology also as an approach complementary to the other recognized conventional methodologies.

Multifarious applications of NMR (high-resolution NMR in liquid-state and in semi-solid matrices, low-field NMR relaxometry, and NMR-imaging) in the analysis of food components and entire food samples are described using examples of different food matrices and different problems related to food safety, traceability, geographical and botanical origin, farming methods, food processing, maturation and ageing, etc. Althoug NMR has not yet been recognized as an official methodology for the food control the numerous applications of NMR reported in the literature show the potenziality of this methodology also as an approach complementary to the other recognized conventional methodologies.

In this study a multi-analytical approach has been performed to characterise the constitutive materials of an ancient painted barkcloth or Tapa. Originating from Wallis Island, Polynesia, this cloth likely served utilitarian or ceremonial purposes and is part of the Felice Junck collection at the Pigorini, Muciv museum of Rome. During a recent conservation project, some micro-samples were taken from the support, brown and black painted areas and were investigated using the complementarity of SEM-EDX, FT-IR, Raman/SERS and solid-state 13C NMR and 1H HR-MAS spectroscopy. The combination of these techniques allowed the chemical characterization of the constitutive materials, from distinguishing the lignin and cellulose content of the support to the use of organic materials including condensed tannins (catechin, anthocyanidins, alkaloids), phlobaphene and vegetal anthraquinone based Morinda genus dyes for the decorations. A primary focus was placed on an understanding of its state of conservation where data of alteration products collected, namely metal carboxylates and oxalates can serve to formulate apt restoration efforts for this specific artefact.

Agar is an interesting and versatile biopolymer capable of forming hydrogels useful in different applications. In particular, in the field of Cultural Heritage agar gels are often used as tools for cleaning the surfaces of artifacts. Agar gels are thermoreversible, peelable materials, exhibiting high retention of water and an intrinsic cleaning capability that can be increased and modulated by loading different cleaning agents. Agar gels are able to solubilize and retain dirt, and allow a confined release of the liquid phase, which is especially important when they are applied on water sensitive substrates. A detailed knowledge of the role of water in agar gels and of water/agar interactions is important to fully understand the properties and performances of agar gels as cleaning materials. Here we report the results of a systematic study aimed at exploring the water state and the types of water (i.e. bound non-freezable, bound freezable and freezable bulk-like) in agar hydrogels prepared from four different types of commercial agar powders. The influence of agar concentration on the water behaviour in the hydrogels was also investigated. The total water content, the identification and quantification of the different types of water was carried out by gravimetric, thermogravimetric and calorimetric analyses, while water mobility and localization in the gel network were investigated by unilateral H-1 NMR. Moreover, H-1 NMR depth profiles of agar gels applied on Noto stone specimens were collected to monitor the gel deformation due to water release and to evaluate the ability of the gel in controlling the water release into a porous material. (C) 2018 Elsevier B.V. All rights reserved.

A portable unilateral nuclear magnetic resonance (NMR) instrument was used to detect in field conditions the water status of leaves of herbaceous crops (Zea mays, Phaseolus vulgaris), mesophyllous trees (Populus nigra), and natural Mediterranean vegetation characterized by water-spending shrubs (Cistus incanus) and water-saving sclerophyllous trees (Quercus ilex). A good relationship was observed between NMR signal, leaf relative water content, and leaf transpiration in herbaceous leaves undergoing fast dehydration or slowly developing a drought stress. A relationship was also observed between NMR signal and water potential of Populus leaves during the development of a water stress and when leaves recovered from the stress. In the natural vegetation, the relationship between NMR signal and water status was found in Cistus, the species characterized by high transpiration rates, when measured during a drought stress period and after a rainfall. In the case of the sclerophyllous Quercus, the NMR signal, the relative water content, and the transpiration rate did not change at different leaf water status, possibly because a large amount of water is compartmentalized in cellular structures and macromolecules. The good association between NMR signal and relative water content was lost in leaves exposed for 24 h to dehydration or to an osmotic stress caused by polyethylene glycol feeding. At this time, the transverse relaxation time became longer than in leaves maintained under optimal water conditions, and two indicators of membrane damage, the ion leakage and the emission of products of membrane lipoxygenation [(Z)-3-hexenal, (Z)-3-hexenol, and (E)-2-hexenol], increased. These results taken all together give information on the physiological state of a leaf under a developing stress and show the usefulness of the NMR instrumentation for screening vegetation health and fitness in natural and cultivated conditions. It is concluded that the portable unilateral NMR instrument may be usefully employed in field conditions to monitor nondestructively the water status of plants and to assist agricultural practices, such as irrigation scheduling, to minimize stomatal closure and the consequent limitation to plant production.

The effectiveness and the mechanism of copper stain removal from stones by agar gels was systematically studied using marble laboratory specimens, stained and cleaned in well-controlled and reproducible conditions. The same cleaning procedure was also applied on the marble base of Napoleon's statue by A. Canova. The water release from agar gels to stones was investigated by capillarity absorption and unilateral Nuclear Magnetic Resonance. The cleaning by different agar gel formulations (pure and added with chemicals) was studied both on the stone substrate (optical microscopy and colour measurements) and in the gels (inductively coupled plasma-atomic emission spectrometry, electron paramagnetic resonance spectroscopy). Among the considered cleaning systems, the most effective ones for copper removal were agar gels 3% containing additives, with no significant difference among the used additives. However, agar gels with additives host copper in different ways: in gels added with ethylenediamine tetraacetic acid (EDTA), all copper centers are coordinated, while copper centers are also dispersed in water within gels added with ammonium citrate tribasic (TAC). The stain cleaning process of stones probably starts with the diffusion of water at the gel-stone interface, but it finds the driving force in the copper coordination. (C) 2016 Elsevier B.V. All rights reserved.

A series of copolyesters (PE) of low molecular weight containing propyloxy-substituted aromatic ring and/or ethylenic sequences between aromatic units were prepared by melt polycondensation between corresponding diacids and diacetates, and used as precursor of poly(ester-co-polyhydrazide) (PEH) new copolymers. The PEs showed to have thermotropic properties, with transition temperatures which depend on the chemical composition and with a good interval of stability of the mesophase. The corresponding PEHs were obtained by high-temperature polycondensation of carboxyl-terminated PEs with terephthalic dihydrazide. The PEHs showed as well a stable mesophase in the melt, and improved thermal stability respect to polyesters. All the polymers were characterized by elemental analysis, inherent viscosity, infrared and 13 C solid state NMR spectroscopy, thermal and thermogravimetric analysis and optical microscopy. Fibers of PEHs were obtained by melt-spinning and characterized by WAXS analysis.