Micro-Raman and FTIR spectroscopy Research Papers (original) (raw)

This paper aims at a full description of the Raman and Infrared spectra of the arsenate mineral tilasite, CaMg(AsO4)F, from Långban, Värmland, Sweden. X-ray diffraction showed the two samples to be phase pure with a monoclinic unit cell of a = 6.683(3) Å, b = 8.950(5) Å, c = 7.572(4) Å, and β = 121.09(2)°. The infrared and Raman spectra were dominated by the arsenate modes. The two highest intensity bands were observed at 850 cm–1 and 831 cm–1 and were assigned to the Raman active ν1 symmetric stretching vibration (A1) and the Raman active triply degenerate ν3 antisymmetric stretching vibration (F2). The Raman and infrared active triply degenerate ν3 antisymmetric stretching vibration (F2) was observed in the infrared spectrum at 822 cm–1, 792 cm–1, and 761 cm–1. The intense Raman band at 465 cm–1 was assigned to the Raman active triply degenerate ν4 bending vibration (F2). The corresponding infrared bands were observed at 523 cm–1, 449 cm–1, and 414 cm–1. The intense Raman band at 329 cm–1 was attributed to the Raman active doubly degenerate ν2 symmetric bending vibration (E). Lowering of the symmetry of the tetrahedral arsenate group led to significant splitting of these modes. The low wavenumber region below 320 cm–1 was assigned to metal-oxygen stretching and lattice vibrations. In the range of 1000–1100 cm–1, four very weak bands were observed. These bands were probably due to the ν3(F2) of a very small amount of phosphate substituted for arsenate in the crystal structure of tilasite.

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- Chemistry, Raman Spectroscopy, Minerals, Vibrational Spectroscopy

Raman and Infrared (IR) spectroscopies provide information about the structure, functional groups and environment of the molecules in the sample. In combination with a microscope, these techniques can also be used to study molecular distributions in heterogeneous samples. Over the past few decades Raman and IR microspectroscopy based techniques have been extensively used to understand fundamental biology and responses of living systems under diverse physiological and pathological conditions. The spectra from biological systems are complex and diverse, owing to their heterogeneous nature consisting of bio-molecules such as proteins, lipids, nucleic acids, carbohydrates etc. Sometimes minor differences may contain critical information. Therefore, interpretation of the results obtained from Raman and IR spectroscopy is difficult and to overcome these intricacies and for deeper insight we need to employ various data mining methods. These methods must be suitable for handling large multidimensional data sets and for exploring the complete spectral information simultaneously. The effective implementation of these multivariate data analysis methods requires the pretreatment of data. The preprocessing of raw data helps in the elimination of noise (unwanted signals) and the enhancement of discriminating features. This review provides an outline of the state-of-the-art data processing tools for multivariate analysis and the various preprocessing methods that are widely used in Raman and IR spectroscopy including imaging for better qualitative and quantitative analysis of biological samples.

- by Rekha Gautam and +3
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- Image Processing, Data Mining, Data Analysis, FTIR spectroscopy

This study was conducted with the aim to extract and purify a
polyphenolic compound “Resveratrol” from the skin of black grapes
Vitisvinifera cultivated in Iraq and synthesis new derivative.
Chemical investigations and tests for the identifications carried out
for the qualification of extracted crystals yield include: general tests
for polyphenoles, aromatic unsaturated compounds, spectrophotometric scanning for λmax screening, High Performance Liquid
Chromatography (HPLC) comparable with standard and Fourier
Transform Infrared (FTIR) to observed groups of compound.
Synthesis new derivatives from purified resveratrol were done
throughout series of reactions accompanied with FTIR for each
derivative. The derivative is (E)-5-(4-(3, 4, 5-trihydroxybenzoyl)
oxy) styryl)-1, 3-phenylene bis (3, 4, 5 tri hydroxyl benzoate). The
IR spectroscopy result confirms the presence of functional groups in
the proposed compounds.

Fibrous proteins (keratin, elastin, collagen, fibroin ...) make up to one third of the proteins of mammals and birds. They are structural proteins with a protective and/or mechanical function. Silk appears to be the ‘simplest’ model because it mainly consists of two small amino acids residues (alanine and glycine). Some silks have comparable or superior mechanical properties compared to those of synthetic fibres and could be used in technical applications (e.g. biomedical) if the variability of their properties can be controlled. This work focuses on the structure of silks from: Bombyx mori (domestic silkworm) degummed or not, Nephila madagascariensis (wild spider, no sericin coating), GM Bombyx mori (including a gene of Nephila) a recombinant spider silk 4RepCT (Escherichia Coli). Silk is analyzed by Raman spectroscopy (and FTIR), uni-axial tensile testing, and also by the coupling of these methods. The analysis of the low wavenumbers region in Raman spectroscopy allowed the characterization of ordered regions of 2-3 microns separated by about 60 microns. This is the first evidence of the heterogeneous structure of silk. Coupling with the uni-axial tensile test shows that these ordered regions are stressed under macroscopic deformation, suggesting silk organization according to Prevorsek’s model, i.e. that the same macromolecular chain belongs to both amorphous and ordered regions. The statistical study of the mechanical properties of silkworm and spider silks shows great dispersion, but a good stability over time (decades). Genetic modification does not improve the fibres mechanical properties but a slight decrease in their variability. Various strategies have been investigated to control the variability: bacterial production, solubilization of silk and films regeneration. The role of water in silk biosynthesis, as well as the effect of various parameters (filtration, pH, drying ...) during the preparation of the films were studied. It was confirmed that the presence of protein aggregates promotes the organization in film and two types of films were prepared. The most amorphous ones have the most interesting mechanical properties, though only a few percent of those from the starting fibres. The fabrication of regenerated silk matrix composites reinforced by silk fibres increases the strength and strain to failure. These initial results are encouraging for the development of silk fibres/regenerated silk matrix composite materials.

- by Marine Wojcieszak and +1
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- Composites, Films, Fibres, Micro-Raman and FTIR spectroscopy

The state of historical artifacts is exacerbated by physical, chemical and biological interactions with the environment. In the absence of appropriate intervention in order to halt or slow down the deterioration these processes can result in a number of negative consequences, starting from incorrect "reading" of a artwork up to its complete loss. Hence, it follows that the detailed knowledge of the composition and structure of the materials must be a fundamental indicator in determining of successfull and long-lasting methods of conservation and restoration. Current scientific research аre making appropriate contributions to the preservation of the cultural heritage, though, for the most part, they are dedicated to improve analytical techniques for the evaluation and identification of the causes of the degradation processes as well as to the development of new methods for effective and safe restoration. Such research is particularly challenging due to the fact that historical objects are unique and irreplaceable to which non-invasive analytical approach must be applied or, at least, to use techniques by taking micro-samples. This analytical review considers the application of non-destructive and micro-chemical methods for preliminary testing - analysis before the treatment of conservation/restoration - of materials used in the preparation of paper artifacts.

Several natural polymers have application in terms of therapeutic treatment of ailments. Chitosan, Aloe Vera and Calendula officinalis have proven wound healing properties individually. It was theorized that a combination of the biopolymer and the plant extract will show an improvement in wound healing properties. Thus, composite films of Aloe Vera extract in Chitosan and C. officinalis petal extract in
Chitosan were prepared and evaluated to ascertain the applicability for wound healing. The chemical composition and mechanical, morphological, and surface characteristics including the antibacterial activity were also evaluated. The optimum conditions for obtaining a maximum percentage of composition were standardized. Their mechanical properties, water absorption characteristics and compatibility were analyzed by tensile tester, FTIR and SEM analyses. The composite films containing aloe vera had higher water absorption capacity and antimicrobial activity as compared to those containing C. officinalis petal extract. The films containing C. officinalis petal extract showed higher tensile strength as compared to those containing Aloe Vera. With the above results, it was concluded that a composite of 25% Aloe Vera in Chitosan can be used as a wound dressing amongst all the combinations.

- by Am Jour of Phytomed & Clinical Therapeut
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- Semiotics, FTIR spectroscopy, Wound Healing, Chitosan

Green synthesis of nanoparticle is an effective and adaptable technique evolved from Nano-biotechnology. Our study focused on a rapid and eco-friendly green method for the synthesis of silver nanoparticles from aqueous solution by using Scallion leaf extract and solvent solution from Banana pseudo stem. Reduction of silver ions to silver Nano particles was visually observed from yellowish green to brown color after the addition of silver nitrate at 2minute reaction time. The synthesized silver nanoparticle were analyzed by UV-Visible spectroscopy by which it showed a absorbance band between 400-500 nm and further characterized by Fourier Transform Infrared Analysis showed a high peak at 1384cm-1 comprising the functional group of C-H rock and alk enes in aqueous extract of banana stem and similarly the highest peak in scallion leaves was 3655.25 cm-1 and showed the characteristics of O-H stretch free hydroxyl group. And finally antibacterial and antifungal activity was performed by well diffusion m ethod but there is no significant effect against E.coli and Staphylococcus whereas zone of inhibition was observed against Aspergillus species when the concentration was increased.

- by Asian Journal for Research and Engineering (AJRE) and +1
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- Synthesis of nanoparticles, FTIR spectroscopy, Nanoparticles, Antimicrobials

This communication aims to present the information concerning the identification of furniture and know-how originally from eastern Mediterranean in Corsica through Middle Bronze Age (1600-1200 b.C.) and Late Bronze Age (1200-800 b.C.).
In this island, the question of the presence of Aegean elements was, for a long time, associated to a theory involving a foreign-born population, the Sherden, a group mentioned within the famous Sea Peoples. After the abandonment of these historic-factual constructions, the insular archaeological research attached itself to the analysis of the sociocultural character of insular groups from the Bronze Age, without trying to connect them to the cultural dynamics from eastern Mediterranean.
After three decades of scientific introspection, it seems important to propose a postponed inventory on this specific issue. The issue of relations between the Aegean and Near-Eastern areas is documented today by several discoveries, revisions on objects and specific analysis made for fifteen years. In the early 2000s, the first formal testimony of the eastern importation recognized in Corsica is a copper ingot of ox-hide typology and Cypriot origin, found out of context in Sant’Anastasia, in the northeast area of the island. This object, published by F. Lo Schiavo, illustrates the integration at least marginal of Corsica into the Mediterranean networks of metal distribution in the late second millennium. This discovery thereby came to partially fulfill an important gap in research, particularly illustrated by the strong contrast expressed by the number of remains of this type between Corsica and Sardinia. At the same time, the realization of analysis (laser ablation coupled to mass spectrometry) on vitreous furniture unearthed during ancient excavations of the sites of Foce, Tiresa and Filitosa permitted to set the context of production, revealing the near-eastern origin of the materials.
More recently, the discovery of a set of ornaments in connection in a sepulchral context of the late Middle Bronze at the site of Campu Stefanu (southwest) allowed obtaining of one of the largest repositories for this type of production throughout the western Mediterranean. This necklace is composed by 25 blue-glass beads of Near-Eastern origin, even Egyptian, and of 29 Baltic amber beads of Aegean typology, which show, in addition, a perfect physical, chemical and morphological superposition with isolated beads from contemporary sepulchral contexts of Sardinia. In this context, the formal non-recognition of Helladic crockery in Corsica, while several cases are known and published in Nuragic area, seems to be explained by a delay in research.
Besides these direct testimonies betraying the importation of exotic prestige goods in Corsica between the fourteenth and the twelfth centuries, recent achievements illustrate the existence of technical transfers between the island and the Mycenaean world around the middle and late second millennium. These phenomena are notably materialized by the strong technical and iconographic analogies observed during repoussé work in metal foils. The matrices recognized in Corsica present indeed profound occurrences with those individualized in Greece, as well as the finished objects to which they are attached. Unlike importing exotica and bullion, repoussé metalwork is not known in Sardinia and peninsular Italy during those times, thereby introducing a direct transfer of know-how between these two territories.
Through these few examples, of which we sense a short-term enrichment, we’ll try to measure and explain the integration of different types of remains within the native society, in order to draw the position of the island amongst the networks between the two basins of the Mediterranean.

- by Ludovic Bellot-Gurlet and +5
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- Archaeology, Prehistoric Archaeology, Island Studies, Cypriot Archaeology

The ophiolitic peridotites in the Wadi Arais area, south Eastern Desert of Egypt, represent a part of Neoproterozoic ophiolites of the Arabian-Nubian Shield (ANS). We found relics of fresh dunites enveloped by serpentinites that show abundances of bastite after orthopyr-oxene, reflecting harzburgite protoliths. The bulk-rock chemistry confirmed the harzburgites as the main protoliths. The primary mantle minerals such as orthopyroxene, olivine and chromian spinel in Arais serpentinites are still preserved. The orthopyroxene has high Mg# [0Mg/ (Mg + Fe 2+)], ~0.923 on average. It shows intra-grain chemical homogeneity and contains, on average, 2.28 wt.% A1 2 O 3 , 0.88 wt.% Cr 2 O 3 and 0.53 wt.% CaO, similar to primary orthopyroxenes in modern forearc peridotites. The olivine in harzburgites has lower Fo (93−94.5) than that in dunites (Fo 94.3 −Fo 95.9). The Arais olivine is similar in NiO (0.47 wt.% on average) and MnO (0.08 wt.% on average) contents to the mantle olivine in primary peridotites. This olivine is high in Fo content, similar to Mg-rich olivines in ANS ophiolitic harzburgites, because of its residual origin. The chromian spinel, found in harzburgites, shows wide ranges of Cr#s [0Cr/(Cr + Al)], 0.46−0.81 and Mg#s, 0.34−0.67. The chromian spinel in dunites shows an intra-grain chemical homogeneity with high Cr#s (0.82−0.86). The chromian spinels in Arais peridotites are low in TiO 2 , 0.05 wt.% and Y Fe [0 Fe 3+ /(Cr + Al + Fe 3+)], ~0.06 on average. They are similar in chemistry to spinels in forearc peridotites. Their compositions associated with olivine's Fo suggest that the harzbur-gites are refractory residues after high-degree partial melting (mainly ~25−30 % partial melting) and dunites are more depleted, similar to highly refractory perido-tites recovered from forearcs. This is in accordance with the partial melting (>20 % melt) obtained by the whole-rock Al 2 O 3 composition. The Arais peridotites have been possibly formed in a sub-arc setting (mantle wedge), where high degrees of partial melting were available during subduction and closing of the Mozambique Ocean, and emplaced in a forearc basin. Their equilibrium temperature based on olivine−spinel thermometry ranges from 650 to 780 °C, and their oxygen fugacity is high (Δlog ƒO 2 02.3 to 2.8), which is characteristic of mantle-wedge peridotites. The Arais peridotites are affected by secondary processes forming microinclusions inside the dunitic olivine, abundances of car-bonates and talc flakes in serpentinites. These microinclusions have been formed by reaction between trapped fluids and host olivine in a closed system. Lizardite and chrysotile, based on Raman analyses, are the main serpentine minerals with lesser antigorite, indicating that serpentines were possibly formed under retrograde metamorphism during exhumation and near the surface at low T (<400 °C).

- by DrMohamed Khedr
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- Mineralogy, Raman Spectroscopy, Mineral Chemistry, Mantle Dynamics

Comprehensive technical examination of an early to mid-2nd century A.D. mummy portrait.

- by Rachel C Sabino
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- Archaeology, Classical Archaeology, Art History, Material Culture Studies

In this study, geometrical optimization, spectroscopic analysis, electronic structure and nuclear magnetic resonance studies of 2-[(methylamino)methyl]pyridine (abbreviated as 2MAMP) were investigated by utilizing DFT/B3LYP with 6-31G (d,p) as basis set. The FTIR and FT-Raman spectra of 2-[(methylamino)methyl]pyridine (2MAMP) have been recorded in the region 4000-400 cm-1 and 4000-50 cm-1 respectively. Complete vibrational assignments, analysis and correlation of the fundamental modes for the title compound were carried out. The harmonic vibrational frequencies were calculated and scaled values have been compared with experimental FTIR and FT-Raman spectra. The observed and calculated frequencies are found to be in good agreement. The theoretical UV-Visible spectrum of the compound was performed by Time Dependent DFT (TD-DFT) approach. The 1H and 13C nuclear magnetic resonance (NMR) chemical shifts of 2MAMP were calculated using the GIAO method by applying B3LYP method. The dipole moment, polarizability and first order hyperpolarizability and mullikken charges of the molecule were calculated using DFT calculations. The polarizability and first hyperpolarizability of the studied molecule indicate that the compound is a good candidate of nonlinear optical materials. The Chemical reactivity and Thermodynamic properties of 2MAMP at different temperatures were also calculated. In addition, molecular electrostatic potential (MEP), frontier molecular orbitals (FMO) analysis were investigated using theoretical calculations. The calculated HOMO and LUMO energies show that charge transfer occurs within the molecule. Keywords: FTIR;FT-RAMAN;UV-Vis; NMR; Hyperpolarizability; 2MAMP

- by khouzami khaoula
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- Materials Science, Chemistry, Physical Chemistry, Chemometrics

The combination of Raman spectroscopy (RS) and scanning electron microscopy (SEM) shows a good poten-tial for non-destructive analysis of painted archaeological ceramics. SEM images reveal the topography and micro-structure of both the ceramic clay and the engobes, and associated microanalyses based on energy-dispersive X-ray spectroscopy (EDS) allow to determine elemental composition of selected surface areas. The elemental com-position coupled with obtained Raman spectra can provide meaningful suggestions of chemical substances contained in the sample. This was verified by analyzing a ceramic shard from the La Tène oppidum Třísov in South Bohe-mia. It was found that its red-brown engobe consists pre-dominantly of hematite and contains also anatase and burnt organic residues. The presence of hematite is con-sistent with the fact that hematite dyes are typical of paint-ed ceramics from this period and region.

This paper deals with the archaeometric characterization of the bricks belonging to Tol-a Ajori Gate, one of the most important excavated sites on the Iranian plateau (Fars, Iran), close to the World Cultural Heritage of Persepolis. The archaeological excavations were carried out between 2011 and 2016 and brought to light a monumental building. The wall of the structure is built with mud and fired bricks sometimes glazed that are very similar to the elements of Babylon's Ishtar Gate. Several investigations were carried out on the bricks in order to investigate the technology process and to compare their composition with local clays, as potential raw materials collected nearby the archaeological site. The brick samples were investigated using different analytical techniques (Optical Microscopy, XRD, XRF, SEM-EDX, FT-IR/ATR, TGA, STA and Micro-Raman) to point out differences in chemical and mineralogical composition. Raw clay samples were submitted to XRD, XRF, SEM-EDX and FT-IR/ATR analyses. A wide homogeneity is present for all the considered bricks: Ca-rich clays with quartz-rich temper were used, this possibly suggesting a common raw material origin. Firing temperatures interval was estimated around 850–900 °C. A multivariate data treatment (PCA and HCA analysis) was applied to the XRF data set acquired for both clays and bricks. PCA suggests that Polvar alluvial clays could be the source raw material for mostly of Tol-e Ajori's bricks and more than one clay deposit was probably used.

- by Maria Letizia Amadori and +2
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- Iranian Archaeology, FTIR spectroscopy, Raman Spectroscopy, Scanning Electron Microscopy

Tellurite and borotellurite glasses containing Bi 2 O 3 and TiO 2 were prepared and structure-property correlations were carried out by density measurements, X-ray diffraction, Differential Scanning Calorimetry (DSC), Raman, FTIR, UV–visible and 11 B MAS-NMR studies. Titanium-tellurite and titanium bismuth tellurite glasses require high melt-cooling rates and were prepared by splat quenching. On adding B 2 O 3 , the glass forming ability (GFA) enhances considerably and bulk glasses could be synthesized at lower quenching rates. The density of glasses shows a direct correlation with molecular mass of the constituents. UV–visible studies were used to determine the optical band gap and refractive index. Raman studies found that the coordination number of tellurium ions with oxygen (N TeeO) remains constant with variation in TiO 2 molar content, while the incorporation of B 2 O 3 and Bi 2 O 3 decreases N TeeO. DSC studies show that the glass transition temperature (T g) increases with B 2 O 3 and TiO 2 concentrations and that T g correlates well with bond enthalpy of the metal oxides. 11 B MAS-NMR studies found that the coordination number of boron with oxygen (N BeO) decreases with increase in B 2 O 3 content while increasing TiO 2 and Bi 2 O 3 concentration does not significantly modify N BeO .

This work deals with the vibrational spectroscopy of 1-chloro-4-nitrobenzene (1C4NB) by means of quantum chemical calculations. The solid phase FT-IR and FT-Raman spectra of 1-chloro-4-nitrobenzene (1C4NB) have been recorded in the regions 4000–400 and 3500-50 cm −1 respectively. The fundamental vibrational frequencies and intensities of vibrational bands were evaluated using density functional theory (DFT) with the standard B3LYP/6-311+G(d.p) method and frequencies were scaled using various scale factors. Simulation of infrared and Raman spectra utilizing the results of these calculations led to excellent overall agreement with the observed spectral patterns. The SQM approach applying selective scaling of the DFT force field was shown to be superior to the uniform scaling method in its ability to allow for making modifications in the band assignment, resulting in more accurate simulation of FT-IR and FT-Raman Spectra. The 1 H and 13 C nuclear magnetic resonance chemical shifts of the molecule were also calculated using the gauge independent atomic orbital (GIAO) method. The theoretical and experimental UV–VIS spectra of 1-chloro-4-nitrobenzene (1C4NB) were recorded and compared and the electronic properties, such as HOMO (Highest Occupied Molecular Orbital) and LUMO (Lowest Unoccupied Molecular Orbital) energies were performed by time-dependent DFT (TD-DFT) approach. Information about the size, shape and charge density distribution and site of chemical reactivity of the molecule has been obtained by mapping electron density isosurface with Molecular Electro Static Potential (MESP).The dipole moment , polarizability, first order hyperpolarizability and mullikkan atomic charges of the title molecule were computed using DFT calculations. In addition Chemical reactivity and thermodynamic properties of 1C4NB at different temperatures were also computed.

- by Rasheed Mp
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- DFT calculation, UV/Vis spectroscopy, NBO analysis, Micro-Raman and FTIR spectroscopy

The Pre-Pottery Neolithic B (PPNB) is the first period in human cultural evolution that is characterized by the extensive production of lime plaster for architectural, decorative and ritual purposes. The production of large quantities of lime plaster requires the operation of a lime kiln, a structure where limestone cobbles are heated to high temperatures (> 600 °C) to obtain quicklime, which is then mixed with water to form a moldable lime putty. However, little is known about lime kilns and plaster production processes during the PPNB. This may be because the technology used at that time was simple and left few traces that are unique to lime plaster production. These include combustion features rich in lime plaster and heat-altered sediments, which are difficult to identify through only a visual inspection of the archaeological context. Here we report the study of a small sinkhole at the Nesher-Ramla quarry in Israel, which yielded Early PPNB artifacts. Using infrared spectrometry and micromorphology of sediments, we identified in-situ deposits of heat-altered sediments rich in fragments of burnt limestone, lime plaster, and wood ash in the form of charcoal, phytoliths and siliceous aggregates, which are features consistent with the operation of a lime kiln. Charred botanical remains were characterized and used for radiocarbon dating, which determined the age of the site at 10,400 cal BP. We therefore conclude, based on the examination of the microscopic archaeological record, that this sinkhole was used as a lime kiln during the Early PPNB.

- by Mauro Sebastianelli and +2
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- Ancient History, Cultural Studies, Russian Studies, Art History

The layered mural paintings inside the church of Santa Maria Antiqua al Foro Romano in Rome have been painted at various times since the Imperial age until the 9 th century. They present a unique and precious evidence of the stylistic, iconographic and technical choices made by patrons and masters in Roman mural painting between the Late Antiquity and the Middle Ages. This research is part of the project Santa Maria Antiqua, organised by the University of Tuscia and directed by Prof. Maria Andaloro with the aim of studying the decorative phases of this monument from an art-historical and a technical point of view. This study focused on the mortars from the mosaics of 4 th-5 th century in the eastern wall, the Pope John VII's Adoration of the Cross (705-707) on the triumphal arch and the Pope Paul I's paintings on the apse (757-768). The purpose of this research was to identify the painting technique used, to characterise original and late materials and to record the colorimetric data of all the different chromatic areas. At first, in situ acquisitions by means of video-microscope and portable spectro-colorimeter were carried out. Samples were taken, prepared as cross sections and slides and then characterized in the laboratory by optical microscopy, Micro-Raman spectroscopy (µ-Raman) and Micro-Infrared Absorption Spectroscopy (µFT-IR). The results allowed us to identify the mortars as lime-pozzolan in all the three decorative phases, but with different lime/pozzolan ratios. Earth pigments were found on the mortar samples taken from the 4 th-5 th century phase, showing that they had been painted before applying the mosaic tiles. The technique used in John VII paintings is fresco, in which lime white was used as an additional binder. Red ochre, lime white, green earth and carbon black were identified on the samples from this phase. The blue shades were obtained either by using a mixture of lime white and carbon black or by Egyptian blue alone. Unoriginal pigments and organic compounds were identified in samples from both John VII's and Paul I's phases, which were probably caused by old conservation treatments and by degradation. Calcium sulphate was detected in the superficial layers of many samples, probably because of the direct contact of the paintings with the soil which had covered the church for centuries. The set of results obtained from this research represents a new piece in the puzzle of the numerous studies performed earlier in the frescoes of Santa Maria Antiqua al Foro Romano, allowing us to have a better understanding of the changes in the techniques and materials used in the context of the Roman mural painting throughout the centuries.

- by Silvia Rita Amato and +2
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- Medieval Art, Medieval Frescoes, Micro-Raman and FTIR spectroscopy, Light microscopy

Samples of prehispanic rock art from Oyola's archaeological site, near the city of Catamarca, Argentina have been analyzed using micro-Raman spectroscopy, SEM-EDS and BSD, and optical microscopy. These samples are representative of diverse figures and non-painted surface of one of the caves at the site: Oyola 7. The pigments employed in the rock art were fully characterized. The red colors are confirmed to be red ochre (hematite) and clay. White areas of the painting have been identified as gypsum whereas black pigment is attributed to graphite. In addition, it was demonstrated that all the samples analyzed, including underlying strata, contain large amounts of calcium oxalate as the mineral whewellite. Because of the distribution along the sample, it was conclude that the presence of this compound is due to biodeterioration produced by microorganisms, fungi, algae or lichens. Moreover, a methodology to differentiate black painting layers from carbon deposition layers from bonfires and to characterize them is presented. These results have a great impact in both chemical and archaeological sciences because allow an interdisciplinary approach bringing relevant information about relative and absolute dating. Finally , the information collected with this methodology establish a sound basis to develop complementary studies between the wall and painting stratigraphies with archaeological excavations resulting in a new and fundamental tool henceforth.

- by Lucas Gheco and +4
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- Archaeology, Rock Art (Archaeology), Raman Spectroscopy, Arqueología

The direct application of corrosion inhibitors on metal surfaces is potentially dangerous for the environment and the restoration operators, thus new conservation strategies are mandatory. In this study, two copper corrosion inhibitors, 1H-benzotriazole (BTA) and 5-phenyl-1H-tetrazole (PT), are encapsulated in a silica nanocontainer, for future application in smart coatings, with the aim to reduce the amount of chemicals used in treatments, their dispersion in the environment and the direct exposure of
the operators to these chemicals. In particular, composite silica nanocapsules, containing the corrosion inhibitors, are prepared via one-step synthesis, based on mini-emulsion polymerisation processes.
The morphology, structure, and texture of these loaded silica nanocontainers are characterised by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and N2 physisorption
(BET/BJH). Micro-Raman spectroscopy (RS) is performed to characterise the composition. UVevisible spectroscopy and thermal analysis (TG/DSC) are performed for the loading and encapsulation efficiency (L%, EE%) study. Synthesised nanocapsules show a core-shell structure and, when loaded with the inhibitors, have size ranging from about 130 to 170 nm and a BET surface area of the order of 800 m2/g. The EE% is maximum
in the case of BTA and decreases to ~52% in the case of PT.

The production and use of the pigment extracted from the murex molluscs is discussed here in association with the purple textile dyeing industry in the Prehistoric Aegean. “True” purple has been identified in a number of archaeological finds dating from the early Late Bronze Age, found in old and recent excavations at three different but contemporary sites: Akrotiri and Raos on Thera, and Trianda on Rhodes. The chemical composition of the shellfish purple pigment either found in lump form or applied on wall paintings is discussed in relation to the archaeological context of several examined finds and with reference to Pliny’s purpurissum. The results of a comprehensive methodology combining new data obtained with molecular spectroscopies (microRaman and FTIR) and already reported data obtained with high performance liquid chromatography coupled with a diode array detector (HPLC–DAD) applied to samples of the murex purple finds are discussed in comparison to published data relating to few other instances of analytically proven murex purple pigment found in the Aegean over the timespan of its documented exploitation.

The potential of laser cleaning for paintings as an alternative to traditional cleaning methods has been recognized, and studies using industrial laser equipment have shown some potential. Irradiation at a wavelength of 248 nm has shown to be the most promising for natural resin varnish and overpaint removal, because it is strongly absorbed by triterpenoid varnish functional groups and associated degradation products (Georgiou 1998). However, it has been suggested that a minimal varnish thickness should remain intact to prevent any radiation from being absorbed by the underlying layers. This is because some painting materials have also shown sensitivity to laser radiation (Bordalo 2006). Research into the mechanisms of alterations which may occur due to laser radiation on resins, pigments and oils and its long-term effects has been scarce, and dispersed in its approach because of the multitude of different materials present in the paint layers (Chappé 2003, Sobott 2003, Melessanaki 2006). Thus, the systematic study of laser radiation interaction with paint materials is still important. The aim of this study was to advance the understanding of the effects that KrF excimer laser irradiation has on pigmented oil paint layers.

- by Rui Bordalo
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- Cultural Studies, Analytical Chemistry, Laser Spectroscopy, Cultural Heritage

This paper discusses the results of a new geo-archaeological study on the nephrite (jade) axes discovered in southern Oman (Dhofar Governorate). The research presents a first account of the geological composition and the morphological structure of such tools and it outlines a preliminary distribution network of jade axe-heads across Southern Arabia. After the discovery of the first analysed sample at Shaqat Jadailah SQJ-3, in the Rub' al-Khali Desert (Dhofar), four other archaeological axe-adze samples collected from southern Oman, were analysed using micro-Raman Spectroscopy and Energy Dispersive X-Ray Fluorescence (ED-XRF). We compared the analysed samples to other nephrite axes collected in the first pioneering exploration of Gertrude Caton-Thompson (Yemen) and Wilfred Thesiger (South Oman). These objects were then correlated with nephrite raw material from the basement exposures in Yemen. Available data show that the raw material originating in Yemen reached the Neolithic groups of Southern Rub' al-Khali and coastal Dhofar most likely during the 6th-5th millennium BC, following a similar path to the obsidian route. The colour, texture and composition, together with the presence of other classes of lithic artefacts such as the trihedral projectile points, indicate that during this period Southern Oman was fully integrated into long-distance exchange networks. The analysis of the collected samples show that they are made exclusively from nephrite, and not from other general "green stones". Considering the high hardness and toughness of the nephrite, this fact allows the hypothesis of a deliberate choice in the selection of raw material for its durability or prestige value.

- by Maria Pia - Maiorano and +1
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- Arid environments, Neolithic Archaeology, X-Ray Fluorescence (XRF) Spectroscopy, Archaeology of Oman

Few archaeological sites in the Americas contain high concentrations of human burials dating back to the
early Holocene. The tropical karstic region of Lagoa Santa, in central Brazil (state of Minas Gerais) is one
of the richest bioanthropological records available to study the behaviors and funerary practices of early
Holocene South Americans, with more than 200 skeletons found so far. One of the key locations to
examine the history of human settlement in Lagoa Santa is the site of Lapa do Santo, a rockshelter known
to contain the oldest rock art and the earliest evidence of funerary complexity in the continent. In this
geoarchaeological investigation we focus on the early Holocene settlement at Lapa do Santo (7.9e12.7 cal
kyBP) applying high-resolution geoarchaeological techniques, such as micromorphology, organic
petrology and mFTIR, on both archaeological, modern reference and experimental samples. This is the
first time that a micro-contextual approach integrated with experimental geoarchaeology has been
applied to study the formation of rockshelter deposits in a tropical setting. Our results show that the
stratigraphic sequence formed under the dual influence of anthropogenic sedimentationdthrough
continuous combustion activitiesdand geogenic sedimentation in the form of oxisol aggregates which
fell from above the limestone cliff into the rockshelter. Intact hearths and remobilized combustion debris,
possibly hearth rake-out, are close to the graves suggesting repeated burning activities as part of the
ritual behavior of early Holocene South Americans. Large amounts of ash are intermixed with heated and
unheated oxisol aggregates. Heated termite mound fragments were also found mixed within the sediments.
Post-depositional alteration of the site includes limited bioturbation and localized, low energy
surface water and sub-surface concentrations of moisture, leading to precipitation of dense, secondary
carbonates. The age inversions can be attributed to the human action of reworking the ashy sediments
and not to post-abandonment processes. Despite this, the overall preservation of the sediments is good
and most human burials can be considered to be in primary context.

- by Ximena Suarez Villagran and +2
- •
- Geography, Archaeology, Prehistoric Archaeology, Sedimentology

This paper deals with designing of miniature versions of Photo-spectroscopy and Massspectroscopy for the detection and analysis of solution samples with the help of a mechanized robotic arm. The proposed methodology is to design a light weight, minimal component yet efficient and accurate designs of the above mentioned spectroscopy techniques which can be mounted of movable Puma robotic arm having 6 degrees of freedom of operation for detection and analysis of sample solutions and COVID-19 samples. The approach involves the least minimal contact of the tester and the patient as the sample solution shall be sent as gargle solution directly to the laboratory for analysis. The lab oriented results generated by the spectroscopy techniques generated significant results in detecting the presence of the viral proteins in the samples. These designs when deployed at larger levels with further advancements can be very effective in carrying out multiple tests in a given period of time and help deliver quicker results of the tests performed. The design is a very flexible design that can be also implemented at household and domestic levels for general solution testing using photo spectrometer. An ideology of testing with bare minimum contact between the patient and the solution analyser, and produce accurate result can be developed from the research.

- by Clara Pandya and +1
- •
- Chemical Engineering, Physics, Optics, Chemistry

Recent researches, coordinated by the University of Ferrara, have led the identification of a rock shelter with rock art, including scratchings and black paintings, signalled by Mr. Lastoria in Spring 2011. The site is nearby the village of Civitanova del Sannio, in Molise, close to a transhumance path, the tratturo Lucera-Castel di Sangro. All the paintings were traced in black pigment and both paintings and engravings are, chronologically and stylistically, attributable to a very long period, from Late Upper Palaeolithic to historical phases, and have been grouped into four main panels. It is hard to define how many figures are represented, due to the bad conservation state; however four black painted zoomorphic figures are recognisable at least and they permit a chronological and cultural comparison with other European findings. Specifically a small size zoomorphic figure, depicted with a black contour line and some spots just under the dorsal line, accentuating its naturalism, i...

- by dario sigari
- •
- Micro-Raman and FTIR spectroscopy

Ochre is an important mineral pigment used by prehistoric hunter-gatherers across the globe, and its use in the Mesolithic is no exception. Using optical microscopy and Raman spectroscopy with micrometre spatial resolution (micro-Raman), we present evidence that confirms unambiguously the use of ochre by hunter-gatherers at Mesolithic sites surrounding Palaeo-Lake Flixton, Vale of Pickering, North Yorkshire, UK. Our results suggest that people collected ochre and processed it in different ways, likely for diverse purposes. The quality and specificity of chemical characterisation possible with micro-Raman facilitates new avenues for further research on ochreous materials in Britain, including provenancing through chemical 'fingerprinting'.

- by Andy Needham and +4
- •
- Mesolithic Archaeology, Mesolithic Europe, Micro-Raman and FTIR spectroscopy
- by Ludovic Bellot-Gurlet and +2
- •
- Archaeology, Mediterranean prehistory, Funerary Archaeology, Resonance Raman Spectroscopy

A beautiful and unique 18th-century Chinese hand-painted wallpaper, found in the so-called Bird Room of Quinta da Francelha, in Lisbon (Portugal), was studied. The history and the symbolism of painted oriental flowers and birds are presented in this poster. The materials and techniques of this wallpaper were studied and its conservation condition assessed. The original materials and also past interventions were characterized by micro-EDXRF, micro-FTIR, micro-Raman and optical microscopy. A new technique for producing cross-sections from paper samples was developed. This allowed the full understanding of the mounting technique of the wallpaper, including the adhesive characterization and numbering of paper layers applied on the wall. Based on these data, a conservation treatment is proposed and discussed, taking into account the structural problems of the building and the environmental conditions.

Vegetable oil is readily available and inexpensive, can be used to synthesize various types of polymers. In our present study, epoxidized punnal oil has been synthesized from punnal oil via peroxyacetic acid generated ‘in situ by treating acetic acid with hydrogen peroxide as an oxygen donor. The epoxidation is catalyzed by using sulphuric acid. The epoxidation is confirmed by iodine value, oxirane oxygen analysis, Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR), and thin-layer chromatography (TLC) analysis. Natural fibers such as jute, sisal, banana, rice husk, etc are locally available in abundance and have excellent physical and mechanical properties, and can be used more effectively in the development of composite materials for various applications. Epoxy composite samples are prepared from the natural fiber with different ratios using triethylamine hardener and phthalic anhydride. The mechanical properties viz. tensile strength and the physical properties observed are discussed in detail.

- by MGES Journals
- •
- Chromatography, Nuclear Magnetic Resonance, Polymers, Natural Polymers

Plastically deformed differently colored diamond crystals from the Internatsionalnaya pipe (Yakutia) have been studied using synchrotron radiation in Laue geometry (Laue-SR method)
and UV-Vis-IR absorption spectroscopy. According to the Laue-SR data, brown, smoky-gray and gray with a light purple-pink hue diamonds have suffered a high degree of deformation
during the post-crystallization period. Strong asterism of Laue spots, intense continuous optical absorption throughout the visible spectrum, monotonically increasing toward shorter
wavelengths, and ‘‘amber centers’’ in the IR region from 4,000 to 6,000 cm-1 are typical of these diamond crystals. Light purplish pink diamonds with gray or brown hue have experienced lesser degree of deformation. This group of diamonds has two absorption bands with maximums at 480 and 550 nm and ‘‘amber centers’’ in the IR region. A distinct polygonization is typical of the inner structure of light purplish pink diamonds. Light purplish pink diamonds have an intensive absorption band with maximum at 550 nm and are characterized by the lack of ‘‘amber centers.’’ The relationship between the deformation levels, diamond color characteristics and manifestation of the ‘‘amber centers’’ in the IR region has been traced based on the obtained results.

- by Rudolf Mashkovtsev
- •
- FTIR spectroscopy, Severe Plastic Deformation, Diamonds, Diamond

Recently, we demonstrated that reduced graphene oxide (rGO) induces transient opening of the blood-brain barrier. When rGO was injected systemically in rats, we observed downregulation in the expression of hippocampal proteins responsible for maintaining paracellular tightness, which suggested weakening of the blood-brain barrier. In addition, analysis of the spatial distribution of rGO by matrix-assisted laser desorption/ionization mass spectrometry imaging and the determination of anatomical, cellular, and molecular parameters suggested that rGO had gained access to the brain. However, it remained unclear whether these events could result in alterations to the molecular homeostasis of the brain. To address this issue, in this study we used Raman spectroscopy and the same rat model and experimental design of the previous study to investigate rGO-provoked molecular changes in the hippocampus. Systemically injected rGO caused a time-dependent reduction in the relative intensity of the Raman bands related to protein and lipid content. Transmission electron microscopy showed alterations in neuronal nuclear membranes and chromatin patterns that could be explained by the Raman spectral alterations. All alterations were reversible and were no longer prominent seven days after rGO administration. We conclude that Raman spectroscopy can be an important complementary technique for monitoring the molecular effects induced by nanomaterials. Introduction. Graphene oxide (GO) is a highly oxidized form of chemically modifi ed graphite. The reduced form of graphene oxide (rGO) is obtained by decreasing the oxygen content of GO under chemical or thermal reducing conditions [1]. The unique chemical, physical, and electronic properties of graphene-based nanomaterials make them suitable for a broad variety of biological applications, such as drug/gene delivery, biosensors, photothermal therapy, stem cell engineering, bioimaging, and neuroscience research [2-4]. We have previously shown that the injection of an aqueous suspension of rGO into rats via a tail vein (i.v.) induced transient disruption of the paracellular tightness of the blood-brain barrier (BBB) in the hippocampus. This was demonstrated by the diffusion of peripheral infused Evans blue dye into the brain and by the infi ltration of the extracellular tracer lanthanum nitrate into the interendothelial cleft accompanied by downregulation of the expression of occludin, β-catenin, and laminin proteins that constitute the matrix/tight-adhesion junction complex in the BBB. The hypothesis that rGO had crossed the BBB was supported by the detection of rGO in the hippocampus and thalamus, as attested by matrix-assisted laser desorption/ionization (MALDI), mass spectrometry imaging (MSI), and determination of the surface morphology and structural parameters of these organs. Most importantly, the changes observed were mild and transitory, i.e., rGO-treated rats showed no signs of neurotoxicity or clinical evidence of discomfort, despite BBB disruption [5]. However, it remained unclear whether the weakening of BBB tightness and the entry of rGO into the brain resulted in alterations to the molecular homeostasis of the BBB.

Infrared absorption spectroscopy is a versatile analytical method that can identify different compounds in archaeological materials and sediments by measuring the portions of the infrared spectrum absorbed by specific molecules. This technique was developed in the 1930s for the characterization of industrial materials, and then applied to the study of artifacts and works of art starting from the 1950s. In the last three decades, infrared spectroscopy has become an established tool in archaeological fieldwork, where it is used to obtain real-time information regarding the archaeological contexts under excavation. Infrared spectrometry can determine the presence of crystalline and disordered inorganic materials, as well as organic materials in archaeological sediments, and thus it is a valuable method in addressing problems related to the preservation of the archaeological record, site formation processes, post-depositional alterations, stratigraphic correlations, absolute chronology, pyrotechnology, and past human activities.

- by Michael B Toffolo
- •
- Archaeology, Physics, Chemistry, Geoarchaeology
- by Carlo Peretto
- •
- Micro-Raman and FTIR spectroscopy

With the help of microwave-assisted technique, zirconia (ZrO 2) nanocrystalline powder was synthesized using a structure directing agent which could be controlled by the nucleation and particle growth. The various characterizations, namely, phase, surface morphology, surface area analysis and optical property were carried out by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET) and UVevisible spectroscopy. From XRD analysis, it was found that the synthesized materials reveal the tetragonal crystalline phase. The average particle size of ZrO 2 was found 14.7 nm by TEM. Specific surface area, pore volume and the pore size for ZrO 2 are 220 m 2 /g, 0.02 cm 3 /g and 10.7 nm investigated by BET, respectively. UVevis DRS spectra of the prepared material confirmed that the Zr atoms are exclusively incorporated within silica framework. Besides, the maximum absorption peaks were observed at 215 nm and 217 nm for as-synthesized and calcined samples, respectively.

A scholarship was awarded through the Goetz Instrument Support Program of a FieldSpec 4 spectrometer during January and February, 2013. This instrument allowed the project to investigate many aspects of the manufacture and use of the objects of interest. Specifically, the aim was to identify and assess materials found on African hair combs, focusing principally on a group from the late 19th and early 20th centuries AD/CE, and to determine the nature of the material (mostly various kinds of wood) from which they are made.

- by Pia Edqvist
- •
- African Diaspora Studies, African History, Spectroscopy, Heritage Conservation

Although the potential of vibrational spectroscopy for biomedical applications has been well demonstrated,
translation into clinical practice has been relatively slow. This Editorial assesses the challenges
facing the field and the potential way forward. While many technological challenges have been addressed
to date, considerable effort is still required to gain acceptance of the techniques among the medical
community, standardise protocols, extend to a clinically relevant scale, and ultimately assess the health
economics underlying clinical deployment. National and international research networks can contribute
much to technology development and standardisation. Ultimately, large-scale funding is required to
engage in clinical trials and instrument development.

- by Bayden Wood
- •
- FTIR spectroscopy, Micro-Raman and FTIR spectroscopy
- by Hugo Gomes
- •
- Archaeology, Geochemistry, Archaeological Science, Ethiopia

Single SH-SY5Y human cancer cells Cellular nucleus and membrane Multivariate analysis X-ray effects on DNA, lipids, proteins and carbohydrates a b s t r a c t Raman micro-spectroscopy was performed in vitro on nuclear and membrane regions of single SH-SY5Y human neuroblastoma cells after irradiation by graded X-ray doses (2, 4, 6, 8 Gy). The acquired spectra were analyzed by principal component analysis (PCA) and interval-PCA (i-PCA) methods. Biochemical changes occurring in the different regions of single cells as a consequence of the radiation exposure were observed in cells fixed immediately after the irradiation. The most relevant effects arose from the analysis of the spectra from the cell nucleus region. The observed changes were discussed in terms of the modifications in the cell cycle, resulting in an increase in the DNA-related signal, a protein rearrangement and changes in lipid and carbohydrates profiles within the nucleus. Potential markers of an apoptotic process in cell population irradiated with 6 and 8-Gy X-ray doses could have been singled out. No significant effects were found in spectra from cells fixed 24 h after the irradiation, thus suggesting the occurrence of repairing processes of the X-ray induced damage.

- by Lorenzo Manti
- •
- Micro-Raman and FTIR spectroscopy

The structure of a selection of arsenate‐and sulphate‐based minerals of the tsumcorite group was studied by the combination of Raman and infrared spectroscopy. A comparison is made with the sulphate‐bearing mineral natrochalcite. Isomorphic substitution of sulphate for arsenate is observed for gartrellite and thometzekite. The positions of the hydroxyl and water stretching vibrations are related to the strength of the hydrogen bond formed between the OH unit and the AsO4 anion. Estimates of the hydrogen bond distances are calculated using a Libowitzky‐type function. Characteristic Raman spectra of the minerals allow the assignment of the bands to specific vibrational modes.

- by J. THEO KLOPROGGE
- •
- Condensed Matter Physics, Arsenic, Raman Spectroscopy, Vibrational Spectroscopy

This study evaluated the effect of combining laser irradiation with fluoride on an enamel microstructure and demineralization by FT-Raman spectroscopy (FTRS). Eighty human enamel slabs were divided into eight groups: (G1) untreated; (G2) acidulated phosphate fluoride application (APF—1.23% F − for 4 min); (G3) Nd:YAG irradiation (84.9 J cm −2 , 60 mJ/pulse); (G4) Nd:YAG + APF; (G5) APF + Nd:YAG; (G6) Er,Cr:YSGG irradiation (2.8 J cm −2 , 12.5 mJ/pulse); (G7) Er,Cr:YSGG + APF; and (G8) APF + Er,Cr:YSGG. After treatment, the samples were submitted to a ten-day pH-cycling model. Chemical changes were determined on the slabs before and after treatment, and also after pH-cycling, by FTRS in the range 400–4000 cm −1. The inorganic bands at 440, 590, 870, 960, 1100 cm −1 , and the organic bands at 1270, 1450, 1670, 2945 cm −1 were considered. Demineralization promoted reduction in organic contents; Nd:YAG laser irradiation promoted loss of carbonate and organic content, while Er,Cr:YSGG did not produce significant changes in the relative band intensities of organic and inorganic contents of the enamel. In lased samples, no effects caused by pH-cycling on enamel were observed. In conclusion, laser treatment and its association with fluoride can somehow interfere with the demineralization dynamics, reducing its effects over the enamel.

- by Goh boon tong
- •
- Materials Engineering, Thin Films, Quantum Confinement, Thin Film