A Study on Corrosion Processes of Archaeological Glass from the Valencian Region (Spain) and its Consolidation Treatment

The combined use of scanning electron microscopy/energy dispersive X-ray microanalysis (SEM/EDX) and square wave voltammetry (SQWV), is used for studying the corrosion processes that have taken place in buried glass from different archaeological sites in the Valencian Region (Spain). The procedures permit a parallel investigation of morphology and chemical composition. Determination of the chemical composition of the glasses and their alteration crust and identification of the elements responsible for the colour has been also carried out using energy dispersive X-ray microanalysis. The electrochemical response of samples attached to paraffin-impregnated graphite electrodes reveals the presence of different iron and manganese oxide species in the browning areas of the corroded glass. Image analysis applied to microphotographs obtained by means of SEM led to the determination of morphological parameters concerning the corrosion phenomena occurring on the surface of the fragments such as thickness of the corrosion layer and its laminated structure. Additionally, measurement of the thickness of the film of polymer used as coating in the consolidation treatments has been carried out using cryo-scanning electron microscopy (cryo-SEM) combined with image analysis.     

Archaeopolymetallurgical study of materials from an Iberian culture site in Spain by scanning electron microscopy with X-ray microanalysis, chemometrics and image analysis

Archaeometallurgical materials from “La Bastida de Moixent”, a site in Valencia (Spain), from the second Iberian iron age (4th Century B.C.) have been studied using metallographic techniques, microanalysis, chemometrics and image analysis. The materials come from various phases of iron production and cupellation of argentiferous lead to obtain silver. Scanning electron microscopy (SEM) is used to determine the morphological, microstructural and topographic characteristics of the samples. Image analysis was used to obtain a numeric estimate of the main components in these materials. X-ray microanalysis (SEM/EDX) provides qualitative and quantitative information about the elements in the sample. The semiquantitative results have been treated by chemometric tools such as Principal Component Analysis (PCA) to group the different archaeological materials. These analyses provide information on the lead and iron metallurgical processes, such as silver production by cupellation used in the period. Macroscopic and microscopic analyses indicate a high quality, acceptably uniform manufactured product, indicating broad technical skill in the later metallurgical process of transformation and refinement of these materials to obtain ingots and manufactured products to trade.     

Energy Dispersive X-Ray Fluorescence Analysis and X-Ray Microanalysis of Medieval Silver Coins

 Austrian medieval silver/copper coins were investigated at their surfaces by energy dispersive X-ray fluorescence analysis (EDXRF) and at the cross-sections by X-ray microanalysis in the scanning electron microscope (SEM/EDX) in order to estimate the error occurring when corroded objects of art and archaeology are analyzed on the surface by non-destructive methods. Additionally, Ag/Cu-standards were treated in diluted sulphuric acid and the depletion of copper on the surface was measured by EDXRF. By calculating the ratio of the Ag-K/Ag-L intensity the process of blanching could be studied.     

Archaeometrical study of paleometallurgical materials from the archaeological site “Cerro de las Balsas — Chinchorro” (La Albufereta, Alacant, Spain)

An Iberian archaeological site located in the east of Spain is one of the most important cupellation centers found in the 4th century b.c. Different metallurgical materials were found in the archaeological site as minerals, cast slags, forged slags, metallic lead, cupella fragments and bronzes. Also was found reverbs remains used for cupper-based materials and cupellation procedure, and hearth forge remains for obtained iron material. The recuperated samples were studied by comparing samples of the same type of material by macroanalysis and microanalysis. The microanalysis and quantitation of the different archaeological materials was carried out by SEM/EDX. The information provides about the knowledge of a metallurgic process such as that of silver production by lead cupellation. The microanalysis results reflect the variety of elements that constitute the slags and other materials, and that come from the forge of the worked metallic materials. Also, the process cupellation was confirmed by the identification of lead and silver. The presence of forge slag corroborates the use of the great amount of recovered heart forges in the excavation like metallurgical structures for the iron work.     

X-ray and scanning electron microscopy archaeometric studies of pigments from the Aguada culture, Argentina

X-ray diffraction (XRD) and scanning electron microscopy (SEM) with energy-dispersive system (EDX) were used in order to obtain mineralogical and chemical composition of white and reddish pigments belonging to the Ambato style of “Aguada” culture, found in the archaeological site of Piedras Blancas (Catamarca, Argentina 500–1100 AD). These pigments are associated with different sectors, two of them being related to funerary context. Due the scarce amount of samples available, it was necessary to develop a new methodology for their study. X-ray diffraction spectra were collected using a low background Si sample holder, which allows the study of small sample amounts (a few milligrams). The mineral quantifications were carried out by applying the Rietveld method to the XRD spectra. The major difficulties arose for reddish pigments, since they contain iron-bearing phases, such as ferruginous clays, in which neither the concentration of Fe^{+ 2} relative to Fe^{+ 3} nor the location in the lattice (occupancy factor) is completely known. With the aim of performing quantitative elemental analysis from SEM-EDX spectra, a special sample holder for the small amounts of available samples was developed. Commercial standards were used in the quantification process and the characteristic intensities were corrected for matrix effects. Micrographs and EDX point spectra allowed the characterization of minor phases and particle analysis. The Rietveld method combined with the new procedure for EDX analysis has proven to be a suitable method for routine quantitative analysis of small amounts of archaeological pigments.     

Analytical study by SEM/EDX and metallographic techniques of materials used in the iron production process during the iberian period

This work is the archaeometric study of different types of materials used in iron production in the Iberian Period (6th-2nd century b.c.). The materials were recovered in several archaeological digs (which makes it possible to date the archaeological remains) on different sites in the Levante area of the Iberian Peninsula. The samples selected for this study belong to different materials used in the ancient iron production process such as ores, slags, finished objects, etc. The use of scanning electron microscopy (SEM) is proposed to observe surface images of the samples to determine their morphological, microstructural and topographic characteristics to obtain valuable information on the materials studied. The study also proposes chemical analysis of the elements in the sample by X-ray microanalysis (SEM/EDX) which provides both qualitative and quantitative information. The archaeometric study suggests that the iron obtained was very good quality, but the process was not economically efficient when viewed from today's perspective. Furthermore, the slag produced in the furnace can be related with the slag or impurities contained in the iron. It has also been possible to relate the ores and slag, some furnace conditions, the use of fluxes and also to differentiate types of slag.     

WDXRF, EPMA and SEM/EDX Quantitative Chemical Analyses of Small Glass Samples

Quantitative chemical analysis is a powerful tool for the classification and discrimination of small glass fragments in forensic and archaeometric analytical issues. In the choice of the analytical method the small dimensions and the irregular shape of the fragments must be accounted for. Several accurate and highly sensitive instrumental techniques successfully employed for the chemical analysis of small glass samples (AAS, ICP-AES and FAAS) are destructive, and therefore unacceptable for these applications. X-ray analytical techniques such as WDXRF, EPMA and SEM/EDX provide means for rapid, non destructive and sensitive multi-elemental analysis of glass fragments. In this study the analytical sensitivity and accuracy of WDXRF, EPMA and SEM/EDX for the analysis of small commercial glass fragments are investigated. The results are compared and discussed in order to establish a relation between the minimum size of glass samples and the accuracy and sensitivity of the analytical methods.     

X-ray and scanning electron microscopy archaeometric studies of pigments from the Aguada culture,Argentina

X-ray diffraction (XRD) and scanning electron microscopy (SEM) with energy-dispersive system (EDX) were used in order to obtain mineralogical and chemical composition of white and reddish pigments belonging to the Ambato style of “Aguada” culture, found in the archaeological site of Piedras Blancas (Catamarca, Argentina 500–1100 AD). These pigments are associated with different sectors, two of them being related to funerary context. Due the scarce amount of samples available, it was necessary to develop a new methodology for their study. X-ray diffraction spectra were collected using a low background Si sample holder, which allows the study of small sample amounts (a few milligrams). The mineral quantifications were carried out by applying the Rietveld method to the XRD spectra. The major difficulties arose for reddish pigments, since they contain iron-bearing phases, such as ferruginous clays, in which neither the concentration of Fe^+ 2 relative to Fe^+ 3 nor the location in the lattice (occupancy factor) is completely known. With the aim of performing quantitative elemental analysis from SEM-EDX spectra, a special sample holder for the small amounts of available samples was developed. Commercial standards were used in the quantification process and the characteristic intensities were corrected for matrix effects. Micrographs and EDX point spectra allowed the characterization of minor phases and particle analysis. The Rietveld method combined with the new procedure for EDX analysis has proven to be a suitable method for routine quantitative analysis of small amounts of archaeological pigments.     

Observation of unusual Griffith’s phase behavior in quadruple perovskite oxide CaCu3Mn4O12 (CCMO) synthesized through chemical route

The CaCu₃Mn₄O₁₂ (CCMO) ceramic was successfully synthesized through the chemical route. The phase formation was confirmed by the X-ray diffraction pattern. Thermogravimetric (TGA), FT-IR, SEM, TEM, EDX, and XPS analysis were performed for investigation of the thermal behavior, phase identification, microstructural analysis, elemental analysis and oxidation state of the CCMO ceramic respectively. FT-IR spectra confirmed the existence of MnO₆ octahedral in body-centered cubic (BCC) complex perovskite oxide that resembles the CaCu₃Ti₄O₁₂ structure. The average particle size was observed by TEM in the range between 100 and 200 nm. AFM shows the average roughness of the surface was found to be in the range of 30 ± 5 nm. XPS and EDX studies confirmed the purity and oxidation state of the CCMO ceramic. The synthesized material shows very interesting unique Griffith’s phase (T_G) results that arise disorder in magnetic susceptibility in which ferromagnetic transition was to be observed in the paramagnetic region.     

NaY zeolite functionalized by sulfamic acid/Cu(OAc)2 as a new and reusable heterogeneous hybrid catalyst for efficient solvent-free formylation of amines

NaY zeolite functionalized by sulfamic acid/Cu(OAc)_2[NaY/SA/Cu(Ⅱ)] was synthesized and used as a new,efficient and recyclable catalyst for preparation of formamides. This novel organic-inorganic hybrid catalyst was characterized by several techniques such as FT-IR, XRD, SEM, EDX and TG analysis.Chemoselectivity, easy procedure, excellent yields, very short reaction times, solvent-free and mild reaction conditions are some benefits of this new protocol.     

Microstructural characterisation of five simulated archaeological copper alloys using light microscopy, scanning electron microscopy, energy dispersive X-ray microanalysis and secondary ion mass spectrometry

This paper describes the microstructural characterisation of five simulated archaeological copper alloys, produced by modern powder technology. The chemical composition of the examined bronzes covers the major families of archaeological bronzes from antiquity until the Roman period. Light microscopy (LM), energy dispersive X-ray microanalysis (EDX), scanning electron microscopy (SEM) as well as two- and three-dimensional secondary ion mass spectrometry (SIMS) have been used to describe the main properties of the alloys. The results show a heterogeneous microstructure on a micrometer scale, formed by metallic and non-metallic phases. The latter are conglomerates of oxides or sulphides of major or minor elements.     

Analysis of post-Byzantine icons from the Church of the Assumption in Cephalonia, Ionian Islands, Greece: a multi-method approach

A multi-method approach has been developed for the characterisation of the proteinaceous binding media, drying oils and pigments present in samples from the panel paintings of the Church of the Assumption in Cephalonia (Ionian Islands, Greece). The analytical protocol involved the use of scanning electron microscopy/energy dispersive X-ray analysis (SEM/EDX), Raman spectroscopy and gas chromatography. The identification of the pigments was achieved by SEM/EDX and Raman spectroscopy. The latter technique was also used for the detection of the binding media, while their characterisation was achieved by gas chromatographic analysis of ethyl chloroformate derivatives. The aim of this multi-method protocol was to obtain as much information as possible from the panel paintings of the Church of the Assumption, through non-destructive methods, before proceeding to gas chromatography. Little scientific information is available for the understanding of the construction technique and the materials used by the post-Byzantine artists and whatever is available comes mainly from artists’ manuals. One of the aims of this paper is to provide a scientific background to the technology of the Ionian post-Byzantine icons.     

Multi-instrument characterization of HiPIMS and DC magnetron sputtered tungsten and copper films

In this work, copper and tungsten were sputtered onto silicon wafers by direct current magnetron sputtering (DCMS) and high-power impulse magnetron sputtering (HiPIMS). The resulting films were characterized by energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), atomic force microscopy (AFM), spectroscopic ellipsometry (SE), and X-ray diffraction (XRD). By EDX and XPS, all the sputtered films showed only the expected metal peaks. By XPS, the surfaces sputtered by DCMS were richer in oxygen than those produced by HiPIMS. By AFM, the surfaces were quite smooth. The root mean square (RMS) roughness values are as follows: 0.83 nm (W, HiPIMS), 1.10 nm (W, DCMS), 0.85 nm (Cu, HiPIMS), and 1.78 nm (Cu, DCMS). By SEM, the HiPIMS films exhibited smaller grain sizes, which was confirmed by XRD. The crystallite sizes estimated by XRD are as follows: 4 nm (W, body-centered cubic, HiPIMS), 13 nm (W, body-centered cubic, DCMS), 7 nm (W, cubic, HiPIMS), 14 nm (W, cubic, DCMS), 25 nm (Cu, HiPIMS), and 35 nm (Cu, DCMS). By SE, the HiPIMS surfaces showed higher refractive indices, which suggested that they were denser and less oxidized than the DCMS surfaces.     

Synthesis and comparative study of catalytic activity between Pd-metallodendrimer and Pd/Cu-bimetallodendrimer nanoparticle-based on triazine

Triazine-based heterogeneous Pd/Cu-bimetallodendrimer Nanoparticle (Pd/Cu-BMDNP) has been synthesized by sequential loading method from palladium containing metallodendrimer (Pd-MD) which was prepared by the reaction of 2,4,6-Triamine-1,3,5-triazine (melamine) with substituted benzoyl chloride using (Ph₃P)₂PdCl₂ in DMSO at 90 °C. SEM and EDX of Pd/Cu-BMDNP showed the nanosized aggregated spherical surface morphology and the presence of Palladium and copper of the NP. Also, the phase was detected as Face Centered Cubic (FCC) structure by XRD analysis. In addition, the average particle size of Pd/Cu bimetallic catalyst was identified as 12–13 nm by TEM investigation. Greater thermal stability of Pd/Cu-BMDNP than Pd-MD was detected from TG and DSC experiments. The Pd-metallodendrimer has been also characterized by IR, ¹H NMR, ¹³C NMR, SEM, EDX, Mass, TG and DSC techniques. The simple recoverability, high reusability, low amount of catalyst loading, negligible amount of catalyst leaching of the heterogeneous Pd/Cu-BMDNP have made more effective catalyst than homogeneous Pd-metallodendrimer for the C–C cross-coupling reaction such as Heck, Glaser, Sonogashira and Suzuki-Miyaura in excellent yields.     

Chemical speciation of heavy metals in soils by use of XAFS spectroscopy and electron microscopical techniques

Pb-contaminated soil samples were investigated using XAFS spectroscopy and SEM/EDX as tools for the analysis of chemical binding forms. The soils originated from the vicinity of a battery factory in Hannover (Germany) and had Pb-contents between 50 g/kg and 140 g/kg. PbCO₃, PbSO₄, PbO and basic PbCO₃ could be identified as the main constituents in the samples by XAFS spectroscopy (EXAFS as well as XANES). This result is consistent with the results of the SEM/EDX investigations on the same soil samples, which showed, that almost all of the lead contained in the soils appears in the form of discrete particles of lead compounds. The EDX analysis of these particles consistently shows the presence of Pb, C, O and S.     

Archaeometrical study of paleometallurgical materials from the archaeological site “Cerro de las Balsas — Chinchorro” (La Albufereta,Alacant, Spain)

An Iberian archaeological site located in the east of Spain is one of the most important cupellation centers found in the 4th century b.c. Different metallurgical materials were found in the archaeological site as minerals, cast slags, forged slags, metallic lead, cupella fragments and bronzes. Also was found reverbs remains used for cupper-based materials and cupellation procedure, and hearth forge remains for obtained iron material. The recuperated samples were studied by comparing samples of the same type of material by macroanalysis and microanalysis. The microanalysis and quantitation of the different archaeological materials was carried out by SEM/EDX. The information provides about the knowledge of a metallurgic process such as that of silver production by lead cupellation. The microanalysis results reflect the variety of elements that constitute the slags and other materials, and that come from the forge of the worked metallic materials. Also, the process cupellation was confirmed by the identification of lead and silver. The presence of forge slag corroborates the use of the great amount of recovered heart forges in the excavation like metallurgical structures for the iron work.     

Quantitation of Metal Ions in Archaeological Glass by Abrasive Stripping Square‐Wave Voltammetry Using Graphite/Polyester Composite Electrodes

A method for identifying Co, Cu, Sb, Sn, Fe, Zn, and Zr pigments in glasses using square‐wave voltammetry as the detection mode is described. It is based on the abrasive attachment of glass microsamples to graphite/polyester composite electrodes. Sample amounts less than 1 μg are used allowing for the study of archaeological samples. In all cases well‐defined anodic stripping peaks corresponding to the oxidation of metal deposits generated at potentials ranging from ?0.6 to ?1.6 V (vs. SCE) are obtained. This response is in agreement with that displayed by the corresponding metal oxides. Quantitative estimates of the relative population of metal ions in glasses are obtained from peak area measurements with an accuracy comparable to that obtained with SEM/EDX.     

Effect of TiO2 nanoparticles on structure and properties of high density polyethylene membranes prepared by thermally induced phase separation method

Polyethylene/TiO₂ membranes were fabricated via thermally induced phase separation (TIPS) method. A set of characterization tests including FE‐SEM, EDX, XRD, DSC, TGA, DMA, mechanical test and relative pure water flux for characterization of membranes were carried out to investigate the effect of TiO₂ nanoparticles on membrane properties. The results of EDX, XRD and TGA analyses confirmed the presence of TiO₂ nanoparticles in the polymer matrix. The results of DSC analysis revealed that the melting point as well as the crystallinity of the membranes increased slightly with increasing TiO₂ content. However, the glass transition temperature of the membranes was not affected by the presence of particles. Addition of nanoparticles also increased storage modulus, loss modulus and tensile strength at break of the membranes due to the stiffness improvement effect of inorganic TiO₂. Finally, it was observed that incorporation of the nanoparticles improved pure water flux of the membranes. Copyright © 2015 John Wiley & Sons, Ltd.     

Chemical speciation of heavy metals in soils by use of XAFS spectroscopy and electron microscopical techniques

Pb-contaminated soil samples were investigated using XAFS spectroscopy and SEM/EDX as tools for the analysis of chemical binding forms. The soils originated from the vicinity of a battery factory in Hannover (Germany) and had Pb-contents between 50 g/kg and 140 g/kg. PbCO₃, PbSO₄, PbO and basic PbCO₃ could be identified as the main constituents in the samples by XAFS spectroscopy (EXAFS as well as XANES). This result is consistent with the results of the SEM/EDX investigations on the same soil samples, which showed, that almost all of the lead contained in the soils appears in the form of discrete particles of lead compounds. The EDX analysis of these particles consistently shows the presence of Pb, C, O and S. Rececived: 1 September 1998 / Revised: 15 December 1998 / Accepted: 18 December 1998     

Characterization of municipal solid waste incineration (MSWI) bottom ash by scanning electron microscopy and quantitative energy dispersive X-ray microanalysis (SEM/EDX)

Scanning electron microscopy (SEM) with energy-dispersive X-ray microanalysis (EDX) is frequently used for morphological and qualitative chemical characterization of different materials. The applicability of this method for phase identification, is, however, often underestimated. The application of SEM/EDX for the characterization of different phases in fresh and altered municipal-waste incinerator bottom-ash samples with high lateral resolution is presented. Polished thin sections were prepared from the samples, but fresh fracture surfaces were also used. The EDX analyses were performed by using the correction procedures of a conventional standardless ZAF correction, a peak-to-background ZAF correction, and a correction method for light-element analysis. Because of their highly reactive properties the bottom-ash SEM samples require a special method of preparation. The method facilitates nondestructive preparation of the sensitive bottom-ash alteration phases (e.g. cement phases, hydroxides, salts) and their microstructures. Received: 18 August 2000 / Revised: 8 November 2000 / Accepted: 12 November 2000