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In this paper we report the results of a study of low-frequency vibrational dynamics and electron-vibration coupling in water in the bulk and confined state, at different hydration percentages. The simultaneous use of both Raman spectroscopy and time-of-flight inelastic neutron scattering allowed us to determine the respective vibrational densities of states (VDOSs), g R eff(ω) and g N(ω). Both the VDOSs show clear evidence of surface-induced vibrational modes, due to the local order distortion with respect to the bulk state.

We present recent incoherent quasi-elastic neutron scattering (IQENS) results, carried out on IN6 time-of-flight spectrometer, performed on water confined into 26 A diameter pores of nanoporous Gelsil glass, as a function of temperature. From the IQENS data analysis it turns out that there is a strong confinement effect on the water molecules by the host glass that reflects, consequentially, a hindered diffusional dynamics. The quasi-elastic response has been explained in terms of two different theoretical models: (i) the well-known Dianoux–Volino model for confined diffusion, and (ii) the MCT model typical of supercooled α-relaxing systems.

In the present study, an innovative methodological approach has been proposed in order to characterize meteoritic samples without removing or causing damage to any part of them. In particular, Raman and X-ray fluorescence (XRF) measurements have been preliminarily performed, using portable instruments, in order to obtain qualitative and semi-quantitative compositional information, respectively. These analyses have been followed and supported by time of flight neutron diffraction (TOF-ND) experiments, which allowed us to perform quantitative mineralogical phase analysis. Such a methodological approach was tested on four meteoritic samples, of different types and sizes, coming from several different regions of the Solar System (e.g., the Moon, Mars and asteroids). The validity and strength of the results obtained using these techniques are discussed and compared with results available in the literature.

The complete knowledge of the porous structure of rocks is necessarily requested for the prediction of the damages induced by salt crystallization. Nevertheless, the geometric description of the porous structure is usually very difficult because of the variability of the size distribution of voids, ranging from nanometers to millimeters, which generally is not accessible by a single methodology. For this reason, a multi-technique approach was used here: the investigation at sub-micrometric dimensional scale (> 0.004 μm) was carried out by Hg intrusion porosimetry (MIP), whereas the study at the nanoscale required Small Angle Neutron Scattering (SANS) analysis. All the results were interpreted in the framework of a fractal model. The analyses were performed on limestones of different geological formations, cropping out in south-eastern Sicily and largely used as building stones in Baroque monuments of the Noto Valley (belonging to the UNESCO Heritage List).

The phase transition from gel to liquid suspension in cyclodextrin (CD)-based hydrogels is in depth monitored by using Fourier transform infrared spectroscopy in attenuated total reflectance geometry. Cyclodextrin nanosponges (CDNS) synthesized by polymerization of CD with the cross-linking agent ethylenediaminetetraacetic dianhydride at different cross-linking agent/CD molar ratios have been left to evolve from gel phase into liquid suspension upon gradual increase of the hydration level. Measurements of the changes occurring in the vibrational dynamics of the system during this transition provide direct evidence of the gel-sol progress of the CNDS hydrogel, by accounting for the connectivity pattern of water molecules concurring to the gelation process. The experimental results clearly indicate that the increase of the hydration level is accompanied by the corresponding increase of the population of H2O molecules engaged in high-connectivity hydrogen-bond networks. The water tetrahedral arrangement is thus dominant above a characteristic cross-over hydration level, experimentally determined for all the investigated samples. The observation of this characteristic cross-over point for the CDNS hydrogel and its correlation with other parameters of the system (e.g. the absorption ability of CDNS and elasticity of the polymer matrix) is, once again, modulated by the cross-linking agent/CD molar ratio. The latter seems indeed to play a key role in defining the nano- and microscopic properties of nanosponge hydrogels.

The effect of the macrocycle size on the gel-to-sol evolution of cyclodextrin-based hydrogel is here investigated by using Fourier transform infrared absorption in attenuated total reflectance geometry (FTIR-ATR). Different types of nanosponges obtained by polymerization of ?- and ?-cyclodextrin (CDNS) with an activated derivative of ethylenediaminetetraacetic acid have been progressively hydrated in order to follow the evolution of these systems from a gel state to a liquid suspension. The in deep analysis of the high-frequency vibrational dynamics of the hydrogel during its gel-sol evolution revealed that the microscopic origin of this phenomenon is strictly connected to different hydrogen bond environments in which water molecules confined in the pores of nanosponges can arrange. By following a well consolidated approach, the OH stretching band of water, clearly observed in the high-frequency range of the vibrational spectra of nanosponges hydrogel, has been decomposed into sub-bands assigned to different arrangements of water molecules at various degrees of cooperativity. A comparison of the diagrams obtained for homologous CDNS prepared from ?- and ?-CD shows how the size of cyclodextrin macrocycle allows to efficiently modulate the gelation points at constant cyclodextrin/crosslinker molar ratio n. © 2014 Springer Science+Business Media Dordrecht.

The vibrational dynamics of a new class of cross-linked polymers made up of cyclodextrins is here investigated in the microscopic range by the joint use of light and inelastic neutron scattering experiments. The effect of increasing the connectivity of the polymeric network on the vibrational dynamics of the system is studied by exploiting the complementarity of these two different probes. The derived densities of vibrational states of the polymers evidence the presence of the characteristic anomalous excess of vibrational modes with respect to the Debye level, already observed in the low-frequency Raman spectra and referred to as boson peak (BP). The overall analysis of the spectra suggests an emerging picture in which the motions of hydrogen atoms of the polymers are progressively hampered when the cross-linking degree of the covalent network increases. At the same time, the frequency and intensity of the BP are found to significantly change by increasing the cross-linking degree of the polymeric network, as clearly suggested by the existence of a scaling-law for the BP evolution. These findings support the conclusion that the growing of the covalent connectivity of the system induces a general modifications of the elastic properties of these cyclodextrin-based polymers, which are, once again, modulated by the cross-linking agent/cyclodextrin molar ratio.

In the present work we show, together with a historiographic research, the results obtained by the application of Raman confocal microspectroscopy on the miniatures contained in three membranous medieval codices (Fondo Vecchio 18 IX–X century, Messanensis S.Salv. Graec. 51 XIII century, Messanensis S.Salv.Graec. 83 XII century). The analysis, which is non-destructive and performed ‘in situˈ on micrometre-sized spots, allowed us to characterize the pigments used, in particular to detect the presence of inorganic substances.

In this work we report a preliminary study of Fourier transform infrared spectroscopy on normal and neoplastic human skin samples suffering from two kinds of cancer, namely epithelioma and basalioma. The analyzed skin samples have been drawn from different parts of the human body, after biopsies. By performing a complex band deconvolution due to the complexity of the tissue composition, the analysis within the considered frequency region (900–4000 cm−1) of the collected IR spectra, allowed us, first of all, to characterize the presence of the pathologies and to show clear different spectral features passing from the normal tissue to the malignant one in particular within the region (1500–2000 cm−1) typical of the lipid bands.

Rayleigh-wing, Raman and quasi-elastic neutron scattering data on water confined into nanoporous glasses (silica 26 A pores), are presented and discussed. The H-bond among water molecules and Si-OH surface groups originates strong hydration effects, that induce more stable structural environments in which the memory of collective modes (the ∼60 cm -1 and ∼190 cm -1 shoulders due to the HB bending and HB stretching modes of water) is lost and the O-H stretching band connected to low-density water tends to disappear. The quasi-elastic neutron response is explained in terms of two available current models: the Dianoux-Volino model and the MCT model.

In the present work IR measurements as a function of temperature, performed, in the (2500−3700) cm-1 region, on ethylene glycol (EG) and its homologous systems, namely ethylene glycol monomethyl ether (EGmE) and ethylene glycol dimethyl ether (EGdE), are presented and discussed. The goal is to analyze the evolution of the O−H stretching fundamental band in a wide range of temperature for systems having identical chemical structure except for the number of hydroxyl end groups, clarifying in this way the processes characterizing the vibrational dynamics of these H-bonded liquids. In particular, the O−H stretching band shape, through a quantitative study performed with FT-IR in the attenuated total reflectance geometry, has been connected to the different transient local environments of hydrogen-bonded molecular groups, and the role played by inter- and intramolecular interactions discussed within the framework of current theories for associated liquids. In addition, temperature-induced isosbestic points obs...

The reorientational dynamics of polymers passing from the monomers (ethylene glycol and propylene glycol) to corresponding oligomers (poly-(propylene glycols)) or to homologous systems (ethylene glycol monomethyl ether and ethylene glycol dimethyl ether), in the bulk state and confined in a sol-gel porous glass with 25 A pores, has been investigated by means of Rayleigh wing scattering, at Iow frequencies. The goal was to study the influence of the chain length and of the physical and chemical traps, connected to the surface interactions and geometrie restrictions respectively, on the mobility of the studied H-bonded liquids. This was possible because of the capability of preventing the interactions with the surfaces of the confining matrix that contain the active silanol groups (Si–OH).

A resveratrol/sulfobutylether-β-cyclodextrin inclusion complex was prepared using the freeze-drying method and characterized in solution through UV-vis spectroscopy, solubility phase studies and Job's plot methods. At the solid state it was characterized using the FTIR-ATR technique. Sulfobutylether-β-cyclodextrin has a high affinity for the drug, and forms an inclusion complex with a 1:1 molar ratio both in solution and as a solid sample. It also has a high stability constant (Kc, 10,114 M(-1)). Complexation strongly increases the water solubility of resveratrol (from 0.03 mg/ml to 1.1 mg/ml, at 25 °C) and positively influences its in vitro anticancer activity which was observed on a human breast cancer cell line (MCF-7). In solid phase, FTIR-ATR revealed itself as being a useful technique in elucidating the complexation mechanism, which it did by emphasizing the functional groups involved in the activation of non-covalent "host-guest" interactions.

The effect of the inclusion into cyclodextrins (CD) cavity on the low-frequency vibrational dynamics of the anti-inflammatory drug ibuprofen (IBP) is here investigated by using Raman and inelastic neutron scattering (INS) experiments. The differences observed in the frequency regime 0-100 cm(-1) between the vibrational modes of uncomplexed racemic and enantiomeric IBP are discussed on the basis of comparison with the quantum chemical computation results, taking into account the distinct symmetry properties of the molecules involved in the formation of the host-guest complex. Subsequently, the inspection of the same frequency range in the spectra of pure host methyl-β-CD and its IBP-inclusion complexes allows one to identify significant modifications in the vibrational dynamics of the guest molecule after their confinement into CD cavity. The experimental Raman and neutron spectra and the derived Raman coupling function C(R)(ω) show that the complexation process gives rise to a complete amorphization of the drug, as well as to a partial hindering, in the vibrational dynamics of complexes, of the modes between 50 and 150 cm(-1) attributed to CD molecule. The comparison between the Raman and neutron spectra of free and complexed IBP in the energy range of the Boson peak (BP) gives evidence that the dynamics related to this specific vibrational feature is sensitive to complexation phenomena.

The favourable accessibility offered by sulfobutyl ether β-cyclodextrin (SBE-β-CD) for the complexation with idebenone (IDE) has been probed, as a function of temperature, in liquid state, by phase solubility study, and, in solid state, by FTIR-ATR technique. The phase solubility results indicated the formation of a IDE/SBE-β-CD inclusion complex with 1:1 molar ratio (AL type diagram), whose apparent stability constants at T = 300, 310, and 320 K have been estimated according to the Higuchi–Connors method. The formation of the inclusion complex has been confirmed on a freeze-dried and a co-precipitated product by FTIR-ATR spectroscopy, monitoring the changes induced by complexation on some characteristic vibrational bands of IDE. Quantitative studies, performed in a wide T range, from T = 250 K to T = 340 K, allowed us to extract information on the effect of temperature on the different hydrogen-bonded environments involving host, guest, and crystallization water molecules. Again, complexation is proved to enhance the stability of the guest, at least in the explored T range.

Quasi-elastic light scattering (QELS) was performed in dilute water in oil microemulsion stabilized by AOT surfactant. The water-soluble polyethylene oxide (PEO) with low molecular weight (8000) added to the microemulsion seems to be confined within the aqueous microphase, since PEO is insoluble in oil (n-heptane). The measurements by QELS of diffusion coefficient, at dilute concentrations, allow determination of the size of the droplets. The phase diagram of the microemulsion undergoes remarkable changes on addition of the polymer. The results show that at fixed R ( water surfactant ratio) the droplets decrease their size as the concentration of polymer increases. This occurrence can be related to the change of interface interaction due to the addition of polymer. Moreover, the hydrodynamic radius, near the critical composition, shows critical behaviour, as a function of the reduced temperature, which seems not to be affected by the polymer addition.

Raman scattering spectra of polymeric aqueous solutions of poly(ethylene glycol) vs. concentration and temperature are presented. We show that the shape of the OH band can be reproduced by a suitable superposition of the spectra of bulk and hydration water. The relative amount of the two contributions changes with concentration and temperature, furnishing information on the number of water molecules bonded to the polymer chain. The results show that, when water concentration increases, water molecules saturate the two lone pairs of each oxygen atom of the polymer in agreement with previous adiabatic compressibility and Incoherent Quasi Elastic Neutron Scattering measurements.

An integrated experimental-numerical approach, based on vibrational spectroscopy techniques and quantum chemical computation methods, has been here implemented and tested on a new class of cyclodextrin-based cross-linked polymers, namely, cyclodextrins nanosponges. By the simultaneous quantitative analysis of FTIR-ATR and Raman spectra in the frequency domains between 1650-1800 and 3000-3700 cm(-1), we individuated reliable physical descriptors directly connected to the cross-linking degree of the polymeric matrices. The comparison between the experimental data and the results of the quantum chemical simulations provided structural information on the involvement of the cyclodextrin chemical groups during the polymerization process. This proposed experimental numerical approach appears to be of general application for the investigation of amorphous polymeric matrices of interest for technological application, for which the use of other experimental techniques is seriously hampered by the low or absent level of crystallinity.

The present work reports a detailed investigation on the speciation of iron in the pigments of decorated pottery fragments of cultural heritage relevance. The fragments come from the Gioiosa Guardia archaeological site in the area of the `Strait of Messina' (Sicily, Southern Italy), and date back to VI-V century BC. The purpose of this study is to characterize the main pigmenting agents responsible for the dark-red coloration of the specimens using non-destructive analytical techniques such as synchrotron radiation X-ray absorption spectroscopy (SR-XAS), a well established technique for cultural heritage and environmental subjects. Absorption spectra were collected at the Fe K-edge on the Italian beamline for absorption and diffraction (BM8-GILDA) at the European Synchrotron Radiation Facility in Grenoble (France). In order to determine the speciation of Fe in the samples, principal component analysis and least-squares fitting procedures were applied to the near-edge part of the absorption spectra (XANES). Details on the local structure around the Fe sites were obtained by analyzing the extended part of the spectra (EXAFS). Furthermore, an accurate determination of the average Fe oxidation state was carried out through analysis of the pre-edge peaks of the absorption spectra. Samples resulted composed of an admixture of Fe(2)O(3) (hematite or maghemite) and magnetite (Fe(3)O(4)), occurring in different relative abundance in the dark- and light-colored areas of the specimens. The results obtained are complementary to information previously obtained by means of instrumental neutron activation analysis, Fourier transform infrared absorbance and time-of-flight neutron diffraction.

In the present work, an analytical characterization of painted plaster samples coming from ancient buildings dated back to 2nd cent. B.C., located in Licata (Sicily, Southern Italy), has been carried out. The investigation has been performed through different spectroscopic techniques: X-ray fluorescence (XRF) using an handheld energy-dispersive XRF analyzer, scanning electron microscopy equipped with an Energy Dispersive Spectrometry microanalysis detector (SEM-EDS) and Fourier transform infrared absorbance spectroscopy (FT-IR). The main goal is to identify the plaster and pigments material. In particular, the XRF investigation of surfaces is the first step for a preliminary elemental characterization. Then, through SEM-EDS measurements, a quantitative analysis of the chemical composition of the plaster and the pigmenting agents along with eventual components related to deterioration processes has been obtained. Finally, FT-IR absorbance spectra have proven to be a useful tool to investigate the molecular nature of the used materials.

Measurements performed by means of Small Angle Neutron Scattering (SANS), Incoherent Quasi Elastic Neutron Scattering (IQENS) and Fourier Transform Infrared (FTIR) techniques on reversed water-in-oil micelles are presented and analysed. This ternary system, constituted by water/surfactant Me+n(AOT)n/oil forms droplets whose shapes and sizes have been determined by SANS. Moreover a strong confinement effect for the H2O molecules, whose dynamical properties reflect themselves on the O-H stretching band (FTIR) and on the low frequency diffusive motions (IQENS), is revealed.

Polarized and depolarized Raman data in mixed isomeric alcohols n-Pentanol and 2-Methyl-2-Butanol are presented. The spectra, obtained as a function of temperature and concentration, have been performed in the intramolecular O—H stretching region. The analysis of the spectral features of the deconvoluted bands, center frequency, percentage intensity and halfwidth, performed in the frame of a previous investigation on the pure components, shows that the aggregative processes, present in these H-bonded liquids, reflect themselves also on this spectral region furnishing evidence that, as evidenciated by other techniques, in the 2M-2BuOH rich region, the formation of hetero-structures, determining a strengthened respect to the more “fragile” pure tertiary alcohol, is present.

The mesoscopic structure of numerous samples of Archaic Ionian Cups found in different archaeological sites of Sicily was non-invasively investigated by means of small angle neutron scattering (SANS). Similar values of the mesoscopic structural parameters, radius of gyration and fractal dimension of the interfaces of the investigated potteries, testify a similar manufacturing technique. Many samples showed mesoscopic planar anisotropy probably due to some external mechanical stress during forging. Similar porosity was found for all the studied ceramics and appeared in general agreement with the Hg porosimetry values. Finally, the firing temperatures were estimated by comparison with raw materials fired under controlled conditions.

A non-invasive time-of-flight neutron diffraction (TOF-ND) analysis has been performed on archaeological pottery fragments from the excavation sites in the “Strait of Messina” area (Sicily, Southern Italy). The revealed quantitative information on the mineralogical composition have been compared, in the case of two samples representative of coarse and fine grained pottery, with the weight fractions of the crystalline phases as obtained from X-ray diffraction on powders (XRPD), for different amounts of extracted powder. From the results, the consistency of these micro-destructive and non-invasive approaches has been checked. This research may contribute to better define the most efficient sampling and analytical method for the determination of mineralogical composition on ceramics different in structure and composition.

Solid inclusion complexes of the amino acid ( d , l )-serine and ( l )-serine with β-cyclodextrin (β-CD) have been investigated by Fourier transform infrared spectroscopy in attenuated total reflectance geometry (FTIR-ATR), in order to put into evidence the effects of chiral properties on the complexation process. The spectral changes induced by complexation in the vibrational spectra of serine have been monitored in the 600–4000 cm−1 range, recognizing the functional groups taking part in the “host–guest” interactions. Again, the quantitative analysis, vs. T, of the C O stretching vibration, by means of a best-fit procedure, furnished the enthalpy changes associated to the binding of serine with β-CD in solid phase. The most stable inclusion complex turned out to be the one formed by ( l )-serine, and then ( d , l )-serine.

The effects of chiral discrimination of ibuprofen (IBP) on the complexation process with methyl-β-cyclodextrin (Me-β-CD) were investigated in the solid phase by FTIR-ATR spectroscopy and numerical simulation. The inclusion mechanism was deduced from the temperature-dependent analysis of the vibrational spectra, in the C=O stretching region, of complexes formed by Me-β-CD with the two enantiomeric and the racemic forms of IBP. The mechanism turned out to be enthalpy-driven, with IBP enantiomers giving rise to more stable inclusion complexes with respect to the racemate.

Numerous samples of archaic transport Corinthian B type amphorae coming from the archaeological excavations of Gela (Sicily, South Italy) were analysed using non-destructive X-ray fluorescence (portable InnovX-Systems ‘Alpha 4000’). Between the 6th and the 5th century BC the Corinthian B amphorae were diffused throughout the Western Mediterranean regions and Greece. Some researchers assigned these amphorae to different production areas, both in Southern Italy and in Greece, although, up to now, the exact attribution to the production centres is still under discussion. In this paper, with the aim to characterise the production sites of this important typology of amphorae, common ceramics, undoubtedly produced in Corinth, Corfu and Sybaris, were also analysed as these important Greek and Magna Graecia cities are considered by the archaeologists as the production centres of ‘Corinthian B’ amphorae. The multivariate analysis, performed on selected elements, clearly distinguished two groups of amphorae which, on the basis of archeological considerations, and by the comparison with reference ceramics, were assigned to Magnae Grecia (Sybaris and surroundings) and Greek productions. Copyright © 2011 John Wiley & Sons, Ltd.

We report on a non-destructive study of Sicilian ceramic fragments of cultural heritage interest, classified as "proto-majolica" pottery and dating back to the twelfth to thirteen centuries AD. The analytical approach used is based on the employment of two totally non-invasive spectroscopic techniques: X-ray fluorescence (XRF), using a portable energy-dispersive XRF analyser, and X-ray absorption spectroscopy, using synchrotron radiation as a probe (SR-XAS). XRF measurements allowed us to collect elemental and spatially resolved information on major and minor constituents of the decorated coating of archaeological pottery fragments, so providing preliminary results on the main components characterizing the surface. In particular, we assigned to Fe and Mn the role of key elements of the colouring agent. With the aim of obtaining more detailed information, we performed SR-XAS measurements at the Fe and Mn K-edges at the Italian BM08 beamline at the European Synchrotron Radiation Facility (Grenoble, France). The experimental data were analysed by applying principal component analysis and least-squares fitting to the near-edge part of the spectra (X-ray absorption near-edge structure) to determine the samples' speciation. From the overall results, umber, a class of brownish pigments characterized by a mixture of hydrated iron and manganese oxides, has been ascribed as a pigmenting agent.

Depolarized low-frequency data on the two isomeric pentanols normal-pentanol (n-PeOH) and 2-methyl-2-butanol (2M-2BuOH) are presented. The measurements, performed over a wide temperature range of the liquid phase, allow the authors to identify two processes that characterize the dynamical response of both the alcohols: the first one, present also in an IQENS experiment performed on the same sample, is connected with the fast rotational jumping of the CH3 groups and results are independent of the nature of the alcohol; the second one, collective in character, allows-by a comparison with the neutron response-the evaluation of the second-rank static Kirkwood correlation factor g2 for both of the alcohols. In addition, a large magnitude of the orientational pair correlation function is detected for the more associative n-PeOH, as compared with that of the more molecular 2M-2BuOH. The reorientational dynamics of the two alcohols is also discussed within the framework of the current theories for Rayleigh wing scattering from associated liquids composed of small molecules.

Sound velocity and density measurements were performed in polymeric aqueous solutions of poly(ethylene glycol) (PEG 600) and poly(ethylene glycol methyl ether) (PEGME 550) as a function of concentration and temperature. The experimental data unambiguously show that the presence of the polymer changes the water structure near the solute, building up a more compact arrangement in which up to two water molecules for each monomeric unity are allowed. Moreover we tested, at low concentration, a model to study the change induced in the polymer hydration by the addition of salt. No direct evidence of interaction between the hydration water of the polymer and salt is brought to light by the obtained results.

Solid inclusion complex of the non-steroidal anti-inflammatory drug Ibuprofen (IBP, (2-[4-(2-methylpropyl)phenyl]-propanoic acid) with (2,6-dimethyl)-β-cyclodextrin (diME-β-CD) has been investigated by Fourier transform infrared spectroscopy in attenuated total reflectance geometry (FTIR-ATR spectroscopy) and numerical simulation. The complexation-induced changes in the FTIR-ATR spectrum of IBP have been interpreted by comparison with the theoretical vibrational wavenumbers and IR intensities of dimeric structures of IBP, derived from symmetric hydrogen bonding of the two carboxylic groups, computed by using Density Functional Theory (DFT) calculations. From temperature-dependent studies, the enthalpy change Δ H associated with the binding of IBP with diME-β-CD for 1:1 stoichiometry, in solid phase, has been estimated.

Selected decorated Renaissance ceramic fragments, found during the excavation of a Sicilian archaeological site (Caltagirone, Sicily, South Italy), have been studied by combining scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDS), and X-ray absorbance spectroscopy (XAS). The study was aimed at providing microchemical and microstructural characterization of the colored glazed coatings in order to elucidate the nature of the pigments in the decorative layers, and in the glaze itself. From the obtained results, the general perspective has been the identification of information to be used for a reliable recognition of the production techniques. In particular, XAS measurements, performed using synchrotron radiation (SR) as the source at the Cu K-edge, in the case of green decorations, provided structural information of the oxidation states and the local chemical environment of copper (neighboring atoms and bond distances).

Ultrasonic and hypersonic measurements on PEG and PEGME aqueous solutions allow us to study the fundamental hydration phenomena occurring in such a system. The data are also discussed in the framework of current theories.

Inclusion complexes of cyclodextrins with nonpolar drugs are a topic of current interest in pharmaceutical science, because they increase the aqueous solubility, chemical stability and bioavailability of poorly water-soluble drugs. By means of elastic incoherent neutron scattering (EINS) technique on the backscattering spectrometer IN13, we measured, in the 150-340 K temperature range, the mean square displacements (MSD) of hydrogen atoms derived from elastic spectra of inclusion complex of beta-cyclodextrin (beta-CyD) with genistein (Gen), a phytoestrogen of great interest for its antioxidant, anticarcinogenic and antiosteoporotic activities. The mobility of the complex has been compared with the single components and the physical mixture. The elastic intensity has been interpreted in terms of the double-well model in the whole temperature range. In the case of Gen, a mainly vibrational dynamics is revealed, while for the other samples, the elastic intensity becomes non-Gaussian above a temperature T(d) congruent with 220-230 K. This dynamical activation, which is represented by an Arrhenius trend, seems to be promoted by the crystallization water molecules. The dynamics of the Gen/beta-CyD inclusion complex is restricted with respect to the physical mixture, due to the action of specific "host-guest" interactions upon complexation. Finally, the dynamical response of our systems to temperature is put in relationship with their thermal stability.

Small angle neutron scattering measurements have been carried out in order to investigate, in microdestructive way, the mesoscopic structure of a variety of potteries of relevance to cultural heritage coming from different Sicilian (Southern Italy) archeological sites belonging to the “Strait of Messina” area and dated back to 7th–3rd century B.C. Data have been compared with the mesoscopic parameters extracted for two series of clayey sediments typical of the Strait of Messina area and fired under controlled conditions. The observed agreement between the features of reference and archeological samples allowed us to estimate the maximum firing temperature of the latter. Information on the pore sizes was obtained by the use of the concept of fractal surface, and compared with porosimetry results.

The ( R , S )-2-acetyl-1-(4′-chlorophenyl)-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline (( R , S )- 1 ) was previously identified as a potent non-competitive AMPA receptor antagonist able to prevent epileptic seizures and reduce AMPA-induced current in electrophysiological experiments. Through the enantiomeric resolution of racemate by chiral HPLC we already demonstrated that the ( R )- 1 enantiomer was the eutomer. Considering the poor water solubility, these compounds have been complexed with β-cyclodextrin (β-CyD). The effect of β-cyclodextrin on the spectral features of molecules was quantitatively investigated, in fully aqueous medium by phase-solubility study and the obtained diagrams suggested that it forms complexes with a molar ratio 1:1. The binding constant ( K ( R )- 1 = 15889 M −1 , K ( R , S )- 1 = 1079 M −1 ) and the complexation efficiency (CE) were calculated. Then the solid complexes in 1:1 molar ratio were prepared by the co-precipitation method and the FTIR-ATR measurements were carried out in order to confirm the host–guest interactions that drive the complexation process, by monitoring the significant differences of the spectra of the complexes with respect to those of the corresponding physical mixtures in the same molar ratio. The experimental data have been compared with molecular modelling studies and we confirmed our hypothesis.

The structure of water in aqueous solutions of polyoxyethylene nonionic amphiphiles C10E5 is studied by Raman scattering along an isothermal path crossing the isotropic one-phase region from 0 to 1 amphiphile volume fraction φ. The isotropic OH stretching vibration spectrum evidences a behavior that depends on the amphiphile concentration. The interpretation of such scattering data leads to the following structural picture for the water in the systems; for φ lower than 0.75, water is partially bound to the oxyethylene groups of the amphiphile; above φ=0.75 all water present in the system is bound. The structure of such bound water presents a local, low dense, four coordinated environment.

The employment of time-of-flight (TOF) neutron diffraction allowed for the quantitative determination of mineral phase contents of the ceramic bulk of several pottery fragments coming from Milazzo and Messina (Sicily, southern Italy). From an historical–artistic point of view, all the samples were dated back to the 12th to 13th centuries AD and classified as belonging to the 'proto-majolica' ceramic class. The adopted procedure is absolutely non-destructive, so that measurements were performed on the entire fragments without any sampling. The information derived, by applying the Rietveld analysis method, allowed us to formulate hypotheses concerning the fabrication processes of the artefacts.

Water adsorbed in nanoporous silica glass has been investigated by Raman spectroscopy. The analysis was performed as a function of temperature (from + 5 to + 75 °C), pore diameter (25 and 75 A) and by changing the nature of the substrate (from hydrophilic to hydrophobic) in order to understand the role played on the dynamic peculiarities of water arrangements both by the bare geometrical confinement and the specific interaction with surface. The experimental spectra, collected in the intra-molecular OH stretching vibrational region, have been decomposed into a sum of sub-bands, representing water molecule arrangements with different types of hydrogen bonding. Hence, we gave a quantitative picture of the temperature and confinement effects on the connectivity pattern. Copyright © 2007 John Wiley & Sons, Ltd.

Most of the “Noto’s Valley” monuments facades, located in different towns of Sicily such as Ragusa Ibla, Modica and Noto, present different colours and in many cases the towns themselves are characterized by evident chromatic variations. The knowledge of colour and in particular the characterization of pigments is of utmost importance in the baroque Sicilian buildings, because the peculiarity of the colour is one of the features that makes the “Noto Valley” monuments a World Cultural Heritage site. The present works aim is to characterise and differentiate the pigments used on the facade of monuments and inside the plasters. In particular, we perform a micro-textural and analytical analysis through scanning electron microscopy (SEM) and a mineralogical investigation through the conjunction of optical microscopy and fourier transform infrared spectroscopy (FT-IR). All the experimental results have allowed us to clearly classify the pigments into earths rich in clay minerals and earth containing gypsum. Furthermore, we also show that the earths rich in clay minerals from Ragusa and Modica areas have local provenance.

Renaissance blue decorated pottery fragments from the archaeological site of Caltagirone (Sicily, Italy) were analysed by scanning electron microscopy – energy dispersive X-ray spectrometry (SEM/EDS). The samples were dated back to 16th century AD on the basis of archaeological observations. The micro-chemical analyses were performed on the ceramic body and the surface decorated layer of the samples. Particularly, the investigation was addressed the characterization of the coating blue decorations. The obtained results allowed us to clearly identify smalt as pigment. Also the presence of arsenic (As) was revealed and the Co/As ratio values were calculated and related to the different process used for the pigment preparation. Further spectroscopic analyses, performed through X-ray absorbance spectroscopy (XAS), carried out at the Co K-edge, confirmed the micro-analytical results and permitted us to identify the oxidation form and the local environment of cobalt atoms.

By pulsed field gradient nuclear magnetic resonance measurements, we investigated the translational diffusion of water confined in the 200 A diameter pores of a sol-gel silica glass. The experiments, performed as a function of the hydration level, showed an enhancement of the self-diffusion coefficient when the water content corresponds to one or fewer monolayers. An explanation for this occurrence has been given in terms of a two-phase process involving a fast molecular exchange between the liquid and the vapor phase. Moreover, in partially filled pores, the surface water diffusion coefficient was measured, and was 4 times lower than the diffusion of liquid confined water in saturated spaces.

We report the results of a measurement of the shear viscosity as a function of the temperature and of the water volume fraction in a three-component sodium di(2-ethylhexyl)sulfosuccinate-decane-water microemulsion. The explored concentration range is 0\ensuremath{\le}\ensuremath{\varphi}\ensuremath{\le}0.73 and the packing fraction of the water-in-oil spherical droplets has been changed in order to obtain a very dense glass-forming liquid. Well-defined maxima in the relative viscosity have been observed at different concentrations and the corresponding temperature values decrease with increasing \ensuremath{\varphi}. The data are discussed considering the system as a colloidal one in which aggregation phenomena are present. In such a way, on the basis of a two-fluid model, we can consider two different contributions to the viscosity. One is directly connected to the repulsive interaction potential, while the second one is directly connected to the attractive interaction that contributes indirectly, through the formation of aggregates. The results are compatible with those previously obtained by light-scattering measurements that gives clear evidence of the presence of a large structural order at the glass transition.

Lecithin/isooctane/water gel is investigated by means of different experimental techniques, namely, depolarized light scattering, ultrasonic and dielectric measurements. Pure isooctane and lecithin/isooctane solution are also tested for comparison. A relaxation process, taking place in the 10−13 s time scale was revealed from the light-scattering experiment, both in the gel and in the solution. This is attributed to the reorientational relaxation of the solvent that keeps its bulk properties. The comparison between the activation enthalpies for the detected process in the gel and in the solution, together with the behavior of the relaxation times vs frequency showed the existence of some influence of the entangled network on the isooctane dynamics. Data from ultrasonic measurements show the existence of the same relaxation process, both in the gel and in the solution, with a relaxed value very near to the one obtained for pure isooctane. The observed dynamics were interpreted as due to the existence of the same elementary microspheres of lecithin in the bulk of the solvent in both systems. The relaxation phenomenon revealed by the dielectric data was analyzed in the frame of a Cole-Cole phenomenological law and associated to the role played by water molecules on lecithin reorientation. The temperature dependence of the observed phenomenon is in agreement with the existence of an entangled polymeric-network.

Aim of the present work is the characterization of several amphora fragments from Sicily (Southern Italy), in order to analyse their composition and relations in terms of mineral contents. Neutron diffraction allowed us to carry out a detailed quantitative identification of the mineral phases present in the samples. This information together with previously published data, allowed us to hypothesize different geographical attributions for the analysed samples. Time-of-flight (TOF) neutron diffraction measurements were performed on both large fragments and powders obtaining mineral phase fractions in good agreement. This approach shows the particular advantage of the technique in cultural heritage studies requiring non-destructive investigations of intact objects.

In this paper, an incoherent quasi-elastic neutron scattering (IQENS) study of the single-particle dynamics of water in fully hydrated Na-A and Mg50-A zeolites at T = 293 K and T = 333 K is presented. In order to probe different time scales, measurements were made at two resolutions, ∼8 µeV and ∼28 µeV. The high-resolution data allowed us to investigate the slower dynamics, which is mainly translational. The low-resolution spectra were used to probe the faster dynamics and distinguish between diffusional and rotational motion. We found that the partial exchange of Na+ with Mg2+ induces: (a) an increase of the available volume for diffusion; (b) a decrease of the fraction of water molecules taking part in the observed jump diffusion process; and (c) a shortening of the residence time.

We report high-resolution (7 μeV, half-width at half-maximum, HWHM) incoherent quasi-elastic neutron scattering data performed on mixtures of Poly(Ethylene Glycol), molecular weight (M.W.) 600 Da, with water. Both samples were prepared using H 2 O and D 2 O in order to be able to separate the polymer dynamics and the hydration water dynamics. Data analysis gives a diffusion coefficient for the polymer which is found to depend on concentration, and suggests that the dynamics of hydration water are much slower than that of bulk water. Moreover, the hydration water exhibits dynamical behaviour typical of confined liquids, and the size of the confinement region increases with water content. Additional properties are explained on the basis of previous results so furnishing a complete characterization of the hydration and of the diffusive properties of these H-bonded systems. These results give a reference picture for the comprehension of the water interaction with natural polymers.

In order to explore the influence of cation substitution on the vibrational dynamics of water molecules in zeolites, the evolution of structural properties of the O-H stretching band of water in fully hydrated Na-A and Mg-exchanged A zeolites has been studied, for different percentages of induced ion exchange, by Fourier transform infrared attenuated total reflection spectroscopy as a function of temperature. The differences revealed in the O-H stretching band shapes have been accounted by fitting the spectra as a sum of four components, corresponding to water molecules exhibiting different types of hydrogen bonding. The dependencies of the relative intensities, peak wave numbers, and bandwidths of the resolved components on temperature and Mg2+ content have been discussed. Evidence of the "structure-maker" role played by a zeolitic surface on physisorbed water, systematically enhanced by increasing the percentage of induced ion exchange, is given in the whole explored temperature range.