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We report the structural characterisation of La1-xNaxMnO$_{3+\delta}$thin films deposited by Rf-magnetron sputtering onto SrTiO3(100) single crystal substrates. In particular, we focussed our attention on a series of samples annealed at different pO2, ranging from 1 to 10-6atm. XRD and microRaman data show an expansion of the perovskite lattice for samples annealed in reducing conditions. This results agree with general manganite gas-solid equilibrium involving the formation of Mn4+as the oxygen content increases. For pO$_{2}\,{<}\,10^{-6}$atm the structure rearranges because of the increasing the oxygen vacancies and the volume of the unit cell shrinks.

Coal fly ash can be considered either as an industrial waste material or as a valuable raw material. This is due to the fact that the main problem in recycling this ash is the possible presence of heavy toxic metals and the necessary reliable treatment to avoid their leaching into the environment. In this paper fluidized bed combustion (FBC) fly ash containing leachable arsenic (As) and vanadium (V) is stabilized with a new proposed technology, based on waste or by-product materials.

The analysis of complex magnetic profiles throughout an ultrathin magnetic films by soft X-ray resonant magnetic reflectivity is discussed. Subnanometer resolution can be achieved allowing the separation of interface and inner layer magnetic contributions as well as the determination of antiferromagnetic and non-collinear spin structures. Reflectivity measurements are carried out up to large scattering angles allowing the determination of the depth-resolved profiles of the out-of-plane magnetic component.

Abstract: The analysis of complex magnetic profiles throughout an ultrathin magnetic films by soft X-ray resonant magnetic reflectivity is discussed. Subnanometer resolution can be achieved allowing the separation of interface and inner layer magnetic contributions as well as the determination of antiferromagnetic and non-collinear spin structures. Reflectivity measurements are carried out up to large scattering angles allowing the determination of the depth-resolved profiles of the out-of-plane magnetic component.

Abstract: One of the main problems in electrochemical Pd deposition of coatings is the hydrogen desorption that causes microcracking phenomena. With the aim of understanding the structural changes due to the hydrogen desorption, the kinetics of the phase transformation from hydride to metallic structure has been followed by in situ X-ray diffraction (XRD) experiments. The structural evolution of samples obtained by two different electrochemical baths has been compared. It was found that the solubility and the desorption kinetics of hydrogen are significantly influenced by the presence of structural defects. Residual stresses have been evaluated for both samples by means of 2D X-ray diffraction (XRD2). The presence of amine complexes in the bath seems to contribute to reducing the crystalline dimension of the Pd-phase, and the differences between the specific volumes of α and β phases is reduced for nanostructured coatings.

Less toxic drugs are needed to combat the human parasite Trypanosoma cruzi (Chagas's disease). One novel target for antitrypanosomal drug design is farnesyltransferase. Several farnesyltransferase inhibitors based on the benzophenone scaffold were assayed in vitro and in vivo with the parasite. The common structural feature of all inhibitors is an amino function which can be protonated. Best in vitro activity (LC50 values 1 and 10 nM, respectively) was recorded for the R-phenylalanine derivative 4a and for the N-propylpiperazinyl derivative 2f. These inhibitors showed no cytotoxicity to cells. When tested in vivo, the survival rates of infected animals receiving the inhibitors at 7 mg/kg body weight/day were 80 and 60% at day 115 postinfection, respectively.

Lanthanum oxyfluoride‐based thin films were grown on SiO2and Si(100) by CVD from La(hfa)3·diglyme (Hhfa = 1,1,1,5,5,5‐hexafluoro‐2,4‐pentanedione; diglyme = bis(2‐metoxyethyl)ether), acting as the source for both lanthanum and fluorine. Film syntheses were performed in an atmosphere of nitrogen + wet oxygen, with particular attention paid to the structural and compositional evolution as a function of the deposition temperature (200–500 °C). To this aim, specimens were subjected to a multi‐technique characterization by means of glancing incidence X‐ray diffraction (GIXRD), X‐ray photoelectron spectroscopy (XPS), secondary ion mass spectrometry (SIMS), and atomic force microscopy (AFM). The formation of nanophasic (crystallite size < 30 nm) films containing LaOF, with a cleaner precursor conversion at the highest deposition temperatures, is evidenced and discussed, highlighting the most critical parameters for obtaining lanthanum oxyfluoride coatings with controlled properties.

In this work we report an analysis on Ni/4H-SiC interfaces aimed at optimizing the ohmic contacts. Several thermal cycles have been performed by rapid thermal annealing checking the possible chemical reactions at the metal semiconductor interfaces. Micro x-ray diffraction and micro Raman techniques have been performed in order to study the interface micro structural evolution. Inter diffusion of each element at the Ni - SiC interface was examined using Auger spectroscopy. Electrical measurements have been performed in order to check the ohmic behavior of the contacts. Finally, a correlation between microstructures evolution and electrical behaviors is reported.

Microstructure and tensile properties of thin walled zinc diecasting alloys have been studied by means of X‐Ray microdiffraction, metallographic analysis and tensile tests in order to evaluate the correlation between the elastic modulus and the component thickness. Results revealed a strong influence of skin layer microstructure on samples stiffness.

The thermal evolution of sol−gel SnO2-based thin films was explored by investigating their structural and morphological features. Nanostructured SnO2 and Pt-doped SnO2 layers were obtained using tetra(tert-butoxy)tin(IV) and Pt(II) acetlylacetonate as precursors. Films were prepared by spin coating from ethanol solutions with different viscosity. After drying at room temperature, they were annealed in air at 673 and 973 K. The surface morphology was analyzed by scanning electron microscopy, atomic force microscopy, and scanning near-field optical microscopy. The structural characterization was performed by means of glancing incidence X-ray diffraction and microdiffraction. Both drying at room temperature and thermal treatment at 673 K resulted in the formation of holes on the surface and inside the films. Their distribution and average dimension were found to depend mainly on the viscosity of the sol precursor, and on the presence of Pt in the films. After annealing at 973 K, surface segregation of PtOx phases and partial filling of the surface holes occurred. The effects of morphology on the electrical transport properties are discussed on the basis of sensitivity, S, measurements (S = Rair/RCO, where Rair and RCO stand for the resistance in air and CO/air, respectively).

In the present paper we analyzed W−Sn−O thin films deposited by the rheotaxial growth and thermal oxidation technique and annealed at different temperatures. The aim of this work is to obtain stable gas sensor materials and to increase the surface-to-volume ratio in the active phase, thus improving the gas sensor sensibility. The structural characterization was performed by means of X-ray diffraction, glancing incidence X-ray diffraction, and X-ray microdiffraction techniques. The morphological characterization was obtained by means of scanning electron microscopy.

Nanostructured (3−6 nm) thin films (80 nm) of SnO2 and Pt-doped SnO2 were obtained by a new sol−gel route using tetra(tert-butoxy)tin(IV) and bis(acetylacetonato)platinum(II) as metal precursors. The results of glancing incidence X-ray diffraction (GIXRD) and X-ray photoelectron spectroscopy (XPS) investigations demonstrated that platinum substituted for tin(IV) in the cassiterite structure. Electron paramagnetic resonance (EPR) and XPS analyses showed that singly ionized paramagnetic oxygen vacancies (VO^•) were formed on pure SnO2 thin films by interaction with CO atmosphere; in Pt-doped SnO2 films, the same defects VO^• fully transferred their electrons to the noble metal so that Pt(IV) became Pt(II) and Pt(0). Such samples successively exposed to air, at room temperature, reduced O2 to O2^-. The behavior was well-detected by EPR measurements, which showed on thin films the presence of Sn(IV)−O2^- species. The surface reactivity agrees with the results of the electrical measurements.

In this paper the oxidation process of Sn/Mo mixed oxides for sensing applications was explored with the aim of investigating the structural properties of these materials and eventually understanding possible relations with functional behaviors. The films were deposited by sputtering following the rules of RGTO (rheothaxial growth and thermal oxidation) and annealed in humid synthetic air at 500, 600, and 700 °C. This is the first time that those materials are deposited by the RGTO technique. The characterization was performed by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDXS), glancing incidence X-ray diffraction (GIXRD), and micro-Raman mapping. It is shown that because of the fabrication process, as a function of the annealing temperature, an addition of a molybdenum layer on tin films determined the formation of oxides species different from that occurring on pure tin films. The Mo content in films treated at 600 and 700 °C decreased, probably because of the molybdenum oxides evaporation.

A novel non-hydrogenated a-C coating has been deposited by sputtering carbon and chromium targets in a closed field unbalanced magnetron sputter ion plating system, with a metallic adhesion layer between the substrate and the cosputtered layer. The properties of these new carbon coatings have been previously compared with those of more conventional hydrogenated metal-containing DLC. Reciprocating and pin-on-disk friction and wear tests have shown that the new carbon coatings have a lower friction coefficient and that their wear resistance is more than one order of magnitude higher than metal-containing hydrogenated DLC coatings.

The analysis of the structural data of high Tcsuperconducting cuprates (HTSCs) shows that large differences exist in X-ray diffraction (XRD) patterns collected from powders and thin films with respect to the single crystal case, depending in many cases on the synthesis routes and material treatments. These differences are often disregarded and the assessment on the purity of the crystalline phase is made on the basis of XRD pattern indexing only. However, when relative intensities of XRD reflections belonging to the same family (e.g. (001)) differ from those obtained from the single crystal structure, the simple pattern indexing is not sufficient for the structural characterization and important structural features are missed. These might be helpful for discussing magnetic or electrical behaviour of specimens, as the related properties may depend on the structural correlation along the caxis. In this article a structural modelling of cuprates of the Bi–Sr–Ca–Cu–O family is proposed by considering the electronic density in the projection perpendicular to the layers of the structure. In particular, the structures of Bi-2201, Bi-2212 and Bi-2223 HTSCs were reduced to monomers and intergrowth effects are simulated by generating polymers with different percentages of these phases. By using this model, much information in terms of intergrowth and site occupancy can be gained from a careful analysis of intensities and widths of 001 reflections.

Structural modeling and simulations are proposed to justify the X-ray diffraction pattern of oxygen-deficient Ti:WO3thin films, where the lack of 2-D and 3-D correlations observed in the structure is ascribed to a random spacing between {1 0 3} crystallographic shear planes while maintaining the defect density of the WO2.9ordered structure. The present phase can be viewed as an intermediate case between the crystalline and the amorphous WO3phases, due to the freezing of the in-plane rotational degree of freedom of the [WO6]6−structural unit.