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High-tin copper-based artefacts, recently discovered during archaeological excavations of the Italic necropolises of ancient Abruzzo (Central Italy), were investigated in order to determine the chemical composition and metallurgical features of the alloys and the micro-chemical and micro-structural nature of the corrosion products grown during the long-term burial. The investigated Cu-based artefacts, dated back to 6th and 5th centuries BC, were defensive weapons, in particular bronze belts and disc armors with embossed decoration and ornamental objects such as rivets, buckles and small rings that were applied to large belts to form complex patterns with the addition of small and large shaped pieces of amber. The analytical characterisation was performed by means of the combined use of scanning electron microscopy coupled with energy dispersive spectroscopy (SEM-EDS), X-ray photoelectron spectroscopy (XPS), optical microscopy (OM) and X-ray diffraction (XRD) analysis. The results put in evidence that the bronze artefacts were manufactured by casting an unusual high-tin bronze alloy in a ceramic bivalve mould thus producing artefacts with a silver-like appearance. In some cases the manufacturing process included also tailored cycles of thermal treatments and hot mechanical working under reducing conditions and well defined thermal parameters in order to shape the high-tin alloys in the form of sheets. The ancient metallurgists have also used low tin bronze alloys coated with a thin layer of tin for producing a highly reflective silver-like appearance. From a corrosion point of view, the main alloying elements have formed degradation products in the form of stratified structures containing tin oxides (romarkite and cassiterite), cuprous oxide, copper carbonates (azurite and malachite) and dangerous chlorine-based compounds (nantokite and atacamite polymorphs). These findings show that there is a strict interaction with the soil components and the pH variation of the different areas of the necropolis, suggesting that post-burial degradation phenomena occur. It can be concluded that SEM-EDS, XRD and OM can be successfully combined for studying the corrosion products of archaeological copper-based artefacts, thus helping to choose the best strategies for the long-lasting conservation of these ancient artworks.

The mineral species forming the patinas naturally grown on copper-based artefacts retrieved from sea-water have been studied by means of the combined use of scanning electron microscopy coupled with energy dispersive spectrometry (SEM+EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and optical microscopy (OM). The selected artefacts include fragments of bronze statues and commonly used objects that were recently found in the Sicilian channel and along the Italian coasts. Our findings show that the composition and structure of the corrosion products is different depending on several parameters and the local environment. Furthermore, the study of the metallurgical features of the artefacts revealed also some interesting manufacturing details. From a conservation point of view, the SEM-EDS, XPS, FTIR, XRD and OM results show, as a whole, that the alloy matrix is often heavily corroded also in the bulk where the ubiquitous and dangerous presence of chlorine was always detected as the main dangerous corroding agent. Chlorine forms nantokite (CuCl) which is the species inducing the cyclic and inexorable copper corrosion commonly called "bronze disease". Other elements from the marine environment that contribute to form the patina are sulphur, phosphorous and seawater cations like Ca and Mg. On the basis of our results, an attempt is made to find a correlation between the nature of the patina, the chemical composition of the objects and the marine retrieving environment where the objects lived for many hundreds, or thousands, years. From a conservation point of view, our findings may be useful to suggest, or select, tailored conservation methods and materials with the purpose to turn the dangerous copper chlorides, or oxy-chlorides (atacamite and its polymorphs), into less reactive and more stable phases. This should hamper the copper cyclic reaction thus ensuring a long-term chemical-physical stability to the bronze artefacts.

The development of active materials for the protection of metallic substrates from corrosion is a task of primary importance for many applications. Several organic compounds were studied to investigate their corrosion inhibition potential in order to replace hazardous compounds [1-2]. The purpose of this research has been the investigation of the efficiency of a new environmental-friendly anticorrosive coating that takes advantage from the synergist effect of a biopolymer matrix combined with amino acids. The inhibition of the corrosion of the copper-based alloys has been studied using Chitosan (CH) as a biopolymer and L-Cysteine (Cy) as amino acid. The latter was selected since, in addition to the amino group, Cy also contains the -SH groups which have a strong affinity with copper. The CH/Cy coatings were optimized paying particular attention to the requirements necessary for their application in the field of cultural heritage. To evaluate the protective efficacy of the coatings, accelerated corrosion tests, purposely tailored, were carried out on bare and coated metal disks. Our tests reveal that the efficiency in the corrosion inhibition increases with a minimum amount of Cy (0.5 mg/ml). The nature of the protective film formed on the copper-based alloy surface was analysed by FTIR spectroscopy 42 whereas the surface modifications due to the corrosion treatments were characterized by Optical Microscopy. The experimental data show that the CH/Cy coatings have a protective action onto the copper-based alloy surface with a consequent inhibition of the corrosion process. [1] G. Giuliani, M. Pascucci, C. Riccucci, E. Messina, M. Salzano de Luna, M. Lavorgna, G.M. Ingo, and G. Di Carlo, Progress in Organic Coatings, 122, 138-146 (2018). [2] M.A. Amin, K.F. Klaled, Q. Mohsen and H.A. Arida, Corrosion Science 52, 1684-1699 (2010).

Main purpose of the work is assembling, testing and optimizing new disposable amperometric biosensors to analyze substances in different application fields as agribusiness, clinical chemistry and environment protection. Many kinds of modified electrodes have been prepared and tested to build portable devices to analyze quickly many analytes, in a simple and cost-effective manner. Bare electrodes of the screen-printed type, with silver as reference, have been used for modification. The glassy carbon electrodes with multi-walled carbon nanotubes or graphene or gold nanoparticles depositions were modified with generation IV ionic liquids. Choline as cation and amino acids, such as glycine, serine, phenylalanine and histidine, as anions have been employed for these ionic liquids. The presence of nanostructured materials on the electrode brings an increased contact surface between analytes and receptor and, consequently, an amplification of the amperometric signal and a better sensibility. Moreover the use of new ionic liquids of generation IV, biologically friendly and water soluble, improves the electronic transfer, facilitating and strengthening the redox reaction nearby the electrode. By immobilizing the proper enzymes onto the modified electrode surface, different compounds of analytical interest can be determined by means of sensitive, properly designed amperometric biosensors. Analytes such as antioxidant components in extra-virgin olive oils, alcohols in beverages and glucose in food matrices have been tested, using a suitable enzyme: microbial lipase, alcohol dehydrogenase and glucose oxidase, respectively.

Gold coated commonly used copper-based objects such as studs, brooches, clasps and a small pendants, dating back to 16th-17th centuries CE, were studied by means of the combined use of FE-SEM/EDS, TOF-SIMS, ?- FTIR, XRD and optical microscopy (OM). In particular, the surface and subsurface chemical features of the gilded objects were investigated, revealing some aspects of the manufacturing methods as well as disclosing the mechanism of degradation occurring during the long-term burial in the soil and the agents involved in this process. Our investigation has made possible to identify the chemistry of the decorative Au layer deposited by using an amalgam, i.e. the fire-gilding, its structure and the corrosion products naturally formed from the interaction with the surrounding environment. The main degradation agents are chlorine, sulphur and phosphorous species that gave rise to the formation of different corrosion products. Indeed the corrosion phenomena are boosted by the metal galvanic coupling which makes gilded-metal art works unstable from a chemical-physical point of view. In perspective of preservation, our results suggest that it is important to prevent the interaction between moisture and nantokite (CuCl), located at the interface between the gilding layer and the substrate, in order to avoid further severe degradation phenomena such as "bronze disease" which transforms the copper substrate into a greenish powder.

An isolated carbon sheet possesses a geometric surface of about 2600 m 2 /g. However, graphene-based materials are often composed by packed sheets in particular when wet chemical synthesis methods are utilised. The exposed Specific Surface Area (SSA) of the material can give useful information about the degree of packing of the graphene-based material. Gas adsorption methods are among the techniques able to estimate the SSA and the porosity of a material. Being the amount of gas adsorbed on the surface related to the SSA, the analysis of the adsorption isotherms allows evaluating the material morphology qualitatively and quantitatively. In this work, two different graphene samples have been synthesized by thermal reduction of GO following a controlled and an explosive pathway, respectively. Nitrogen adsorption isotherms at 77 K have been measured, permitting to compare the features of the samples. Briefly, GO suspension was obtained by exploiting a modified Hummers method (1) and subsequently subjected to freeze drying (2) process to obtain Lyophilised Graphene Oxide (LGO hereafter). The reduction of the LGO was then promoted by thermal activation exploiting a controlled reduction pathway, obtaining thus a Reduced Graphene Oxide (RGO hereafter), and an explosive reduction pathway, producing an Exploded Graphene Oxide (EGO hereafter). Both the samples were obtained under a vacuum of 10 -2 mmHg. The materials were characterized by means of Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy and Nitrogen adsorption analyses at 77 K. The BET method (3) was applied to calculate the SSA. Nitrogen adsorption isotherms at 77 K are reported in Fig. 1. The sample EGO exhibits a type IV isotherm, typical of mesoporous samples. The isotherm presents a hysteresis loop of type H3 that is commonly attributed to the presence of slit-like pores, typical in the aggregates of sheet-like particles. The sample RGO exhibits a type II isotherm, typical of non-porous or macroporous samples. The BET SSA calculated from the EGO and RGO isotherms are ~580 m 2 /g and ~90 m 2 /g, respectively. By comparing nitrogen adsorption measurements of the RGO and EGO samples it can be evidenced that the RGO can be considered as composed by aggregates of ~30 sheets, the explosively obtained EGO sample can be considered as a 4-5 sheets system. The explosion phenomenon appears to be effective in separating the hexagonal carbon layers. Further analyses are currently in progress to confirm the obtained results by using CO 2 gas as probe molecule. Differences in the reduction process of Graphene Oxide can drastically alter morphological properties of the obtained samples. Nitrogen adsorption measurements show that the exploded sample possesses a significantly higher specific surface area than the reduced one, due to a higher degree of disorder and high spacing between graphene sheets. On the other side, he low area measured for the Reduced Graphene Oxide sample can be due to a slight separation of the graphene sheets.

By means of scanning electron microscopy combined with energy dispersive X-ray spectroscopy (SEM-EDS) and X-ray photoelectron spectroscopy (XPS), counterfeited Roman Republican coins are investigated to decipher some aspects of the manufacturing methods and to evaluate the technological ability of the Roman metallurgists to produce thin silver films. The results demonstrate that over 2000 ago important advances in the technology of thin film deposition on metal substrates were attained by Romans that produced counterfeited coins by combining sophisticated micro- and nano-plating methods and tailored surface chemical modification based on the mercury-silvering process. The ancient metallurgists were able systematically to manipulate metals at a micro and nano scale to produce adherent precious metal layers with a uniform thickness ranging from one to a few micrometers. Romans were able to create the appearance of solid silver coins without knowledge about the chemical-physical processes but using only their experienced skill [1]. Furthermore, the results suggest that, contrary to the more recent times, counterfeited coins were likely produced by the issuing official authorities too. The production was aimed firstly to save expensive metals as much as possible allowing profitable large-scale production at a lower cost. The driving forces could have been a lack of precious metals, an unexpected need to circulate coins for trade and/or a combinations of social, political and economic factors that requested a change in money supply. Finally, useful information on degradation agents have been achieved to tailor the selection of conservation methods able to save these important witnesses of art, technology and economy. [1] G.M. Ingo, G. Guida, E. Angelini, G. Di Carlo, A. Mezzi, G. Padeletti, Acc. Chem. Res. 46, 2365 (2013).

Copper-based alloys are affect by degradation processes leading to the formation of surface patinas, whose composition depends on several parameters such as the alloy composition, metallurgical features and environmental conditions. Naturally grown patinas are typically detected onto the surface of modern bronze works of art [1] and strictly affect the surface reactivity. The production of representative patinas onto bronze substrates is a key issues in order to obtain model systems which can be used for the development and validation of appropriate conservation strategies. In this study, we have prepared different artificial representative patinas by using a quaternary copper-based alloy (Cu-Sn-Zn-Pb) with chemical composition and metallurgical features similar to those of valuable modern works of art [1]. In order to produce degradation products commonly observed onto their surface, chloride and sulphate species were used to induce corrosion processes. Different patinas were produced by changing some experimental parameters, as concentration of corrosive species, temperature and ageing time. The composition and structural properties of the patinas were investigated by attenuated total reflectance Fourier transform infrared spectroscopy, X-ray diffraction, optical microscopy and scanning electron microscopy with energy dispersive X-ray spectroscopy. The results allow to identify degradation products and to distinguish polymorph species. In the case of chloride induced patina formation, red Cu2O (cuprite) and green Cu2(OH)3Cl polymorphs were mainly detected. When the patina formation is induced by sulphate species, it mainly consists of blue Cu4SO4(OH)6 polymorphs. [1] D.E. Couture-Rigert, P.J. Sirois, E.A. Moffatt, Studies in Conservation, 57, 142 (2012).

In this work the synthesis and characterisation of ZrxTi1-xO2 (ZT) grown via a non conventional MOCVD apparatus on both silicon and platinum coated substrates are described. The samples have been chemically, morphologically and structurally characterised by AFM, XRD, SEM + FEG and XPS. Also high and low frequencies electrical characterisation has been performed to evaluate a possible application of such materials as high-k dielectrics. (C) 2003 Elsevier B.V. All rights reserved.

To promote lacquer adhesion, different thin films of tin oxides have been grown by means of electrochemical treatments on low tin-plated ferritic steels. The chemical composition and semiconducting properties of the oxide films have been studied by means of the combimed use of X-ray photoelectron spectroscopy (XPS) and electrochemical analytical techniques. These materials were coated with an epoxy-phenolic lacquer and subject t to wet lacquer adhesion tests. Along with these adhesion measurements, XPS and electrochemical results show that the lacquer a adhesion is enhanced when there is an increase in the extent of p-type semiconduction and when the oxide film thickness is a few nanometres thick.

A noteworthy number of metallic artefacts dating back to 673-645 BC have been found during excavations in the Ayanis Fortress, near the lake of Van. They are large bronze shields, quivers, helmets, arrows and plates, some of which are decorated with cuneiform inscriptions, and demonstrate a high-level quality of technological competence reached by the ancient craftsmen of Ayanis during the reign of King Rusa II. The artefacts have been studied from a microchemical, micromorphological and microstructural point of view by means of different techniques, from optical microscopy to scanning electron microscopy (SEM), to X-ray diffraction. Microchemical and microstructural investigations showed metallurgical features of the bronze artefacts and of the corrosion products' layered structures that can be explained in terms of manufacturing processes (repeated cycles of mechanical work and annealing thermal treatments) and environmental context (presence of high amounts of chlorides in the soil that preferentially attack the bronze along the grain boundaries). In particular, the repeated cycles of mechanical work and annealing thermal treatments were carried out to restore the ductility and the malleability of the alloy, thus inducing the crystallisation and the growth of flattened grains as well as impurities segregation phenomena along grain boundaries.

A noteworthy number of metallic artefacts dating back to 673-645 BC have been found during excavations in the Ayanis Fortress, near the lake of Van. They are large bronze shields, quivers, helmets, arrows and plates, some of which are decorated with cuneiform inscriptions, and demonstrate a high-level quality of technological competence reached by the ancient craftsmen of Ayanis during the reign of King Rusa II. The artefacts have been studied from a microchemical, micromorphological and microstructural point of view by means of different techniques, from optical microscopy to scanning electron microscopy (SEM), to X-ray diffraction. Microchemical and microstructural investigations showed metallurgical features of the bronze artefacts and of the corrosion products' layered structures that can be explained in terms of manufacturing processes (repeated cycles of mechanical work and annealing thermal treatments) and environmental context (presence of high amounts of chlorides in the soil that preferentially attack the bronze along the grain boundaries). In particular, the repeated cycles of mechanical work and annealing thermal treatments were carried out to restore the ductility and the malleability of the alloy, thus inducing the crystallisation and the growth of flattened grains as well as impurities segregation phenomena along grain boundaries. Copyright (C) 2010 John Wiley & Sons, Ltd.

In order to promote lacquer adhesion different surface treatments have been carried out on low tinplated steels (LTS). The surface chemical composition and semiconduction properties of these materials have been studied by means of a combined use of X-ray photo-electron spectroscopy (XPS), in high energy resolution, and electrochemical analytical techniques. Along with the adhesion measurements, this study has shown that lacquer adhesion is enhanced with increase in the extent of p-type semiconduction, achieved by increasing the amount of anodically grown Sn4+ oxide and by a passive film of Cr(III) oxide. It has been suggested that p-type oxides (acceptor sites) interact, during the lacquer curing with lacquer organic functional groups to form chemical and stable bonds. The effect on the lacquer adhesion of the oxide thickness and their hydration depth has been also discussed.

By means of X-ray photoelectron spectroscopy (XPS), simultaneous differential thermal analysis (DTA) and thermogravimetric analysis (TGA), changes of valence state and surface chemical composition of a 25.5CeO 2 2.5Y 2 O 3 72ZrO 2 (percentages by weight) fine powder, suitable for producing sintered components, have been studied as a function of temperature (up to 1550°C) and atmosphere (flowing N 2 (90%)-H 2 (10%) and static air). XPS results lead to the evaluation of the valence state of cerium, zirconium and yttrium both in the starting powder and in thermal-treated powders. In particular, the analysis of the characteristic satellite structure, binding energy and peak lineshape in the Ce3d spectra show that cerium in the starting powder is confirmed to be Ce(IV) with a small amount of Ce(III) and that after the thermal treatments cerium is either unaffected, partially or fully reduced to Ce(III). DTA and TGA thermograms confirm this redox behaviour and show, for static-air treatment, the presence of a strong and sharp exothermic peak at about 410°C, which is interpreted as being due to the oxidation of a small amount of Ce 2 O 3 . On the contrary, under reducing conditions in the range 630 to 730°C, the powder is affected by a remarkable weight loss owing to the Ce(IV) reduction to Ce(III) oxide. The change of valence state of zirconium, due to the reduction of ZrO 2 to Zr 2 O 3 , under reducing condition at 1050°C has been also monitored by XPS. Furthermore, starting from ≥ 900°C. XPS results show the occurennce of segregation phenomena of both bulk-dissolved impurities, such as silicon, sodium, iron and aluminium as well as of yttrium-stabilizing oxide. The Wagner two-dimensional chemical state plots for silicon and aluminium indicate that the chemical nature of the segregated phase is ascribable to an infinite chain silicate of sodium and yttrium with the presence of aluminium at higher temperatures. The effect of the aforecited chemical aspects on the final properties of sintered materials, is also discussed.

The EFESTUS project aims and results are presented and briefly discussed by describing first the problems to be solved and then the scientific objectives, the achieved scientific results and the policy impact. Finally the dissemination and exploitation of the main results are described with the list of the participating 12 Partners from ( Mediterranean Countries.

This chapter will attempt to provide an overview of the ways in which the immensely complex knowledge of extractive metallurgy, melting, alloying and metal working has come into being in the ancient Mediterranean basin, thus progressively modifying the life and economy of humankind. A study of this magnitude embracing many of the countries that have created human civilisation cannot be treated in one chapter or in one volume; however, we will describe some relevant steps of the metallurgy diffusion in the Mediterranean basin from Anatolia to the Syrian-Palestinian coast including the Egyptian and Jordanian areas by giving importance both to historical-archaeological considerations and to the material evidence that discloses the relevant technological innovations. The technology of metallurgy is an aspect of technology as well as of history. Extractive metallurgy, in particular, which consists of mining, smelting and melting and metal working has had great influence on the political, social and economical history of humankind due to the continuous search for new metal sources and routes of trade, to the development and transfer of technological innovation and to military implications.

Archaeological and historic metal artefacts made of iron, copper and silver alloys from the mediterranean are often found in museums in poor state of conservation due to the uncontrolled environmental conditions and are in urgent need of new conservation straegies, Under the auspices of the 6th framework priority INCO PROMET project, innovative protection systems are being developed with the cooperation of 21 Partners from 11 Countries of the Mediterranean basin : Egypt, France, Greece, Italy, Jordan, Malta, Morocco, Spain, Syrian Arab Republic, Turkey and including Czech Republic.

The LIBS technique has been utilized for a long time in the Cultural Heritage field. Moreover, the potential of this technique for accurate quantitative analysis could be greatly improved using an innovative experimental setup based on the use of two laser pulses suitably retarded. On the basis of the analyses performed on a set of certified bronze samples, reference curves were built and Limits of Detection (LOD) were calculated in order to obtain quantitative information about the composition of three ancient bronze coins. The coins are Punic, of a kind struck in many Punic mints of the Mediterranean basin such as Carthage and in Sicilian cities, as well as in Sardinia, in III cent BC. The detection limits for the elements of interest were calculated under the optimum conditions for the doublepulse configuration and compared with those obtained under the optimum conditions for single-pulse configuration. Significantly improved detection limits were achieved, for all the elements investigated.

Research activities regarding the conservation of Cultural Heritage have significantly increased in recent years in every European and Mediterranean country, as artefacts are important remains of our civilisation and valuable signs of how human being evolved in terms of art and history. One major concern of curators and archaeologists is the preservation of archaeological objects taken out of excavations and kept in museums. In the case of bronzes and other copper based alloys, the degradation phenomena occurring during burial or exposure to a museum atmosphere usually initiate by the formation of a cuprite layer, which darkens the surface, and then, depending on the environment surrounding the sample, various corrosion products of copper II can develop, giving either a brown-black colour or a green one to the surface. This process damages the alloys, as the copper required to form the corrosion products comes from the metal core, which can then considerably decrease, indeed disappear, following the corrosion rate. It is therefore crucial to find methods of protection and conservation of these metallic artefacts that prevent them from getting damaged. In this paper, we present analyses carried out on Italian copper-based archaeological value artefacts selected as a function of the archaeological context and of the chemical composition and structure; and on aged copper-based reference alloys of similar composition to that of the ancient alloys, in order to characterise their corrosion products and modelize the mechanism of the degradation process. The archaeological artefacts came from two different sites in Sardinia and the riverbanks of the Tiber. They were analysed by means of optical and scanning electron microscopy, X-ray diffraction and fluorescence performed with portable instrument and glow discharge optical emission spectroscopy. The corrosion layer was also characterised by electrochemical impedance spectroscopy. The reference alloys were produced with the similar composition determined after the analyses of a large selection of artefacts. These analyses gave us either ternary or quaternary alloys of copper, tin, zinc and lead. These alloys were then buried in soils coming from the Sardinian and Roman sites, in presence of water. Ageing tests were run on these samples in a climatic chamber, where the samples were put for 1, 4 and 7 months. The aged samples were characterised by means of the same techniques than those used for the artefacts. The first results obtained on the artefacts show the formation of malachite on samples coming from sites exposed to a marine and chlorinated atmosphere and a partial mineralisation of the alloys due to their interaction with the soils. Cuprite is also detected as a major component of the corrosion layer. For the one-month degraded reference alloys, wide dark red and red spots of cuprite have formed a first thin corrosion layer. Green traces of malachite are also noticeable on samples buried in soils containing higher water content than the field capacity

Surveys of metal collections housed in 12 museums throughtout the Mediterranean basin have been carried out using a systematic survey approach, which involves using either a statistical methodoly in asssessing the technogly and conditions of a large sample of the objects, a data-mining technique to survey a random sample from the collection, or in case of silver based objects in depth diagnostic investigation of the chemical and mineralogical properties of a representative number of artefacts.

In the framework of the EFESTUS project financially supported by the European Commission (INCOMED contract No. ICA3-CT-2002-10030) and aimed to find tailored strategies for the conservation of archaeological value bronze artefacts from Mediterranean Countries, an Anglo-Arabic integrated information system has been developed. The system allows communication based on a web site, the control and the exchange of information within the partners and European and Mediterranean Museum and Conservation Institutions and includes also a digital Atlas with detailed physical-chemical information on the representative Cu-based artifacts related to the burial conditions, degradation mechanism and conservation methods. The main objective of the Anglo-Arabic web site is the dissemination of the project results in order to spread the range of advantages offered by the knowledge of the Cu-base degradation mechanisms, by the identification of the chemical and metallurgical features of the Cu-base ancient alloys and by the employment of the traditional or innovative conservation methodologies and products. The main EFESTUS Partners effort has been aimed for producing data sheets published in the EFESTUS Anglo-Arabic web site for presenting the EFESTUS project results and in particular the main chemical and metallurgical features as well as the nature of the corrosion products and of the archaeological soils. In these data sheets, the most significant results achieved in the framework of the Work Packages and information concerning the Mediterranean Cu-based archaeological artefacts found during the archaeological excavation of the selected archaeological contexts are reported and described with some information concerning the archaeological sites and the main soil chemical-physical parameters. Furthermore, the data sheets describe the main chemical, micro-chemical, micro-structural and metallurgical features of the bronze objects. Furthermore, the data sheets will be used for producing a Mediterranean Atlas where are clearly identified the best practises for the cleaning and the conservation of the Mediterranean copper based artefacts in order to ensure them a long-life and a sustainable management as well as to avoid a further degradation.

A novel research approach focused on innovative materials and methods to assure the long-term stability of bronze archaeological artefacts during exhibition and storage is reported. The work deals with the application of advanced analytical techniques and development, characterisation and testing of materials and procedures for the conservation, protection and restoration of ancient Cu-based alloy artefacts. Our first aim was the selection of Cu-based alloy artefacts from different archaeological sites in Southern Italy with respect of chemical composition, metallurgical features and corrosion products. This step allowed the identification of the ancient alloys, the study of natural patinas and the identification of the involved degrading agents and mechanisms. Then the selection of long-term reliable, safe and environmentally friendly strategies for conservation was carried out. An original analytical approach based on the production of reference Cu-based alloys submitted to accelerated degradation tests war used to produce corroded samples for testing new materials with corrosion inhibiting properties.

In the framework of the EFESTUS project financially supported by the European Commission (INCOMED contract No. ICA3-CT-2002-10030) and aimed to find tailored strategies for the conservation of archaeological value bronze artefacts from Mediterranean Countries, well-defined groups of Cu-based alloys archaeological objects have been selected as a function of the archaeological context, of the degradation state and of the expected chemical composition and structure. The archaeological artefacts have been studied by means of the combined use of different analytical techniques such as SEM-EDS, XRD, OM, GDOES, XPS, ICP-MS, AAS, DTA-TG, XRF and XPS. The results indicate that their chemical composition is very wide and includes all kinds of the ancient Cu-base alloys such as copper, low tin and high tin also leaded materials and that the artefacts have been subjected to different degradation mechanisms. In order to find a relationship between burial condition and degradation mechanisms, also the archaeological soils have been studied and the different corroding agents identified. Furthermore, in order to ensure a long-term and stable life to the archaeological bronze artefacts the storage and exhibition atmosphere of 8 important Mediterranean Museums have been monitored by using a purposely-developed strategy and equipments that have been used for determining the environmental key parameters affecting the long-term stability of artefacts during exhibition or storage in the Museum. Finally, a wide series of reference Cu-base alloys not commercially available and whose chemical composition, micro-chemical structure and metallurgical features are similar to those of ancient alloys has been produced. These reference Cu-base alloys have been used to test the effectiveness of new low toxic materials for the reliable and long-term conservation of archaeological bronze objects.

Thermal stability, mechanical properties and chemical and physical characteristics of a type of gypsum bonded investment commonly used for the preparation of moulds for investment casting have been studied, with regard to the burnout cycle. Scanning electron microscopy coupled with micro-chemical analysis by X-ray energy dispersion (SEM + EDS), X-ray diffractometry (XRD), differential thermal analysis coupled with thermogravimetry (DTA - TG), porosimetry and compressive strength evaluation have been used for this research. The results show a remarkable effect of burnout cycle temperature and duration on mechanical properties and thermal stability of the investment. These variations have been correlated with thermal expansion, porosity, size pore distribution produced by the parameters of the burnout cycle in the two components of the material, silica and gypsum, respectively. From the point of view of the technology, the results show the possibility of managing the final properties of gypsum based investment in the best way, by suitable adaptation of burnout cycle time, maximum temperature, heating and cooling rate.

Zirconium titanate based ceramics are commonly used as dielectrics in microwave devices. The basic compound, ZxTiO(4), has long been known to have a low temperature coefficient of the dielectric permittivity, while the compound Zr0.8Sn0.2TiO4 has optimal properties at microwave frequencies (epsilon(r) similar to 38, T-cc = 0 ppm degrees C-1 and tan delta approximate to 1 x 10(-4)). Thin films of these materials appear as very promising dielectric layers for the integration in MIM and MIS structures. In this work we describe the pulsed laser deposition of zirconium titanate based materials on Pt/TiO2/SiO2/(100)Si substrates. The influence of the different processing parameters on film orientation, microstructure and chemical composition is discussed. Surface roughness, chemical composition and microstructural features of the films were optimised to achieve the most suitable dielectric properties. A laser fluence J approximate to 4.5J/cm(2), a substrate temperature T-s 550-600 degrees C and 5 x 10(-2) mbar of oxygen atmosphere are required to achieve highly oriented and crystalline films. The departure from these optima deposition conditions causes variations on the film composition, microstructure and residual strains. The permittivity of the films is affected by the presence of foreign crystalline phases. Crystalline and single phase thin films having a dense columnar structure is a fundamental requirement to achieve low loss dielectric films. (c) 2004 Published by Elsevier B.V.

By means of the combined use of different analytical techniques, the micro-chemical structure of silver- or gold-plated objects dating back to the Greek, Roman, Barbarian, Dark and Middle Age periods have been studied in order to identify the different used plating techniques, and to elucidate some aspects of the manufacturing techniques. The attention has been focused on coins and luxury objects such as jewels, coins, buckles and decorative items. This innovative approach has been utilised in order to gain further insight into the micro-chemical structure of the external regions of the objects, as well as of the bulk metallurgical features. The results indicate that several methods were used in ancient times by the craftsmen, including the simple mechanical application of a thin malleable gold foil, or the most complex and sophisticated method based on the use of mercury i.e., the so called fire gilding. This latter method was used to coat copper or silver core with a thin film of precious metals and could be considered the most important advance in the technology of gilding to be made in antiquity.

Roman mirrors have been characterized by means of different analytical techniques, OM, SEM+EDS, GDOES, XRD. They are made with the classic bronzes used by Romans for manufacturing luxurious mirrors (high tin amount, 27-30%; lead amount, 7-8%); on ancient mirrors the following three intermetallic compounds may be foud:?-Cu6Sn5, 61.5 wt%Sn;?-Cu3Sn, 38.2 wt% Sn; ?-Cu31Sn8, 32.6% Sn. These latter phases and a+d eutectoid may be indentified when deliberate tinning of low tin bronzes or copper is carried out, while the mirrors produced with high tin leaded bronzes are characterised by a more complex microstructure and this is especially true if the alloy has been quenched. The mirrors show a front side, shiny, and a back side, dull. The microstructure of the front side is characterized by the presence of a noticeable surface tin oxide enrichment, by an inner layer with small rounded lead globules dispersed in a very fine homogeneous a+d eutectoid cast structure. The microstructure of the back side is characterised by a homogeneous and mineralised a+d eutectoid ghost structure throughout, with deep corrosion attacks. The Sn surface enrichment seems to be responsible for the dark grey silvery lustrous appearance of the front side of the mirrors still reflecting after more than 2000 years of burial.

Sixteen fragments of white plaster from the basins of the wine press XV and from the miqveh in the Area C and 7 samples of iron from the Areas B and C have been analysed at the Institute of Material Chemistry of the National Research Council in Rome in order to carry out an archaeometric investigation concerning their nature, their chemical composition and their micro-structure. This study was aimed to better understand the real usefulness of these materials and the way they were used for manufacturing. In particular, the nature of the mortars is important from a historical point of view since this could help distinguish the various materials with different composite characteristics. These, in their turn, would shed light on the various phases of construction or the eventual restoration and the methods this needs to adopt.

SiO2-like coatings have been deposited onto silver-based alloys by means of plasma-enhanced chemical vapor deposition (PECVD) fed with a tetraethoxysilane/oxygen mixture in order to study their capability to protect the alloys from tarnishing. Chemical and morphological characterization of the coatings has been carried out by means of X-ray photoelectron spectroscopy (XPS), infrared absorption spectroscopy, and scanning electron microscopy, while tarnishing susceptibility has been evaluated by means of visual inspection after intermittent immersions in Na2S solution at room temperature. It has been found that coatings deposited from oxygen-rich mixtures at high input power are characterized by excellent protective properties.

The microchemical structure of the oxide scale grown on a polycrystalline Nimonic 80 A nickel-based superalloy as a function of the air high-temperature treatment (up to 950 degreesC) has been studied by means of the combined use of glow discharge optical emission spectrometry (GDOES), scanning electron microscopy with energy-dispersive spectrometry (SEM + EDS) and x-ray diffraction (XRD). The results disclose the morphology, the microchemical structure and the in-depth elemental chemical composition of the oxide layers and their variation as a function of the temperature of the air thermal treatment. Furthermore, GDOES, SEM + EDS and XRD results show the different oxidation behaviours of both main alloying and minor reactive elements that induce the formation of a stratified oxide structure. Copyright (C) 2002 John Wiley Sons, Ltd.

With the use of different complementary analytical techniques as SEM+EDS (scanning electron microscopy + energy dispersive spectrometry), GDOES (glow discharge optical emission spectroscopy), OM (optical microscopy), XRD (X-ray diffraction) and electrochemical techniques, as EIS (electrochemical impedance spectroscopy), a microchemical and microstructural characterization of the corrosion products of metallic artefacts of archaeological and artistic interest has been carried out. In particular high tin bronze artefacts, as Roman mirrors, found during archaeological excavation of the Phoenician-Punic and then Roman city of Tharros (north-western Sardinia), have been investigated, together with Roman and middle Ages gilded artefacts.

In the last years, zirconium titanate thin films Zr x Ti 1− x O 4 (ZT) turned out to have very interesting dielectric properties, which suggests a use in microwave integrated systems. In this work, the synthesis and characterization of Zr x Ti 1− x O 4 (ZT) thin films grown via MOCVD are described, giving emphasis to the study of their structural, chemical and physical properties, with relation to the different process parameters applied. All samples analysed by XRD, AFM, SEM and EDS, show a great dependence on substrate temperature and reactor pressure on the kinetic of growth as well as on the chemical, crystallographic, morphological and microstructural features.

In order to locate the geographical iron ore sources exploited for producing the early iron artefacts and slags found at Tell Afis (north-western Syria), the iron ore outcrops of Syrian Kurdistan, located at Kerry and Alamdar, have been sampled. The iron ores have been subjected to micro-chemical characterisation and to smelting processes carried out adopting experimental conditions similar, as soon as possible, to those used in an antique furnace. Attention as been focused on the micro-chemical aspects involved during the smelting process and on the chemical composition of the slags that result from the process. this micro-chemical information has been compared with those obtained from the study of the early iron smelting slags and artefacts and a relationship between the iron ores of Kerry and the early iron metallurgy products has been found.

By means of the combined use of scanning electron microscopy+energy dispersive spectrometry (SEM+EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), differential thermal analysis (DTA) and thermogravimetry (TG), the thermal decomposition of gypsum and gypsum bonded investment used for casting jewellery products has been studied in order to gain a further insight into the origin of the gas porosity in gold-based alloys produced via lost wax casting. The occurrence of the defect is related to the thermal decomposition of CaSO4 that constitutes with silica the investment material and the decomposition of which takes place at a temperature very close to the casting temperature of some typical gold alloys. The decrease of the thermal decomposition temperature of gypsum is induced by the presence of silica and is related to the surface acid-base interaction between SiO2 and CaSO4. On the base of these results, the solid state thermal decomposition of calcium sulphate in the presence of other metal oxides characterised by different acid-base nature has been investigated and a correlation between the surface acid-base properties measured as isoelectric point of the solid surface (IEPS) and via XPS analysis and the temperature of CaSO4 thermal decomposition is observed.