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International audience; A combination of high field solid-state MAS NMR spectroscopy, X-ray diffraction, and firstprinciples calculations is used to elucidate the crystalline structure of CsSc3F10. At room temperature, this phase was found to crystallize in the Pmma (n°51) space group with a = 8.0837(1) Å, b = 7.5764(1) Å, and c = 6.8127(1) Å. The remarkable feature of CsSc3F10 is an unusual high cesium coordination number of 18. 45 Sc-19 F D-HMQC NMR method has been employed to investigate the connectivity of scandium with fluorine atoms. NMR parameters were determined using first principle DFT calculations and compared with experimentally obtained data.

Purpose The purpose of this paper is to investigate the effect of doping element on the microwave absorption performance of hexagonal nano boron nitride (h-nBN)-reinforced basalt fabric (BF)/epoxy composites. A new type of hybrid composite that will be produced by the use of boron nitride as an additive that leads to increased radar absorption capability will be developed and a new material that can be used in aeronautical radar applications. Design/methodology/approach This study is focused on the microwave absorption properties of h-nBN doped basalt fabric-reinforced epoxy composites. Basalt fabric (BF)/epoxy composites (pure composites) and the BF/h-nBN (1 Wt.% h-nBN doped composites) hybrid composites were fabricated by vacuum infusion method. Phase identification of the composites were performed using X-ray diffraction (XRD), the 2θ scan range was from 10 to 60 with the scanning speed of 3°/min and surface morphologies of the composites were investigated using scanning electron microscopy (SEM). Microwave properties of samples were investigated through transmission/reflection measurements in Agilent brand 2-Port PNA-L Network Analyzer in the frequency range of 3–18 GHz. The prepared sample is positioned between two horn antennas with and without metal plate. Findings Experimental results show that h-nBN doped composite was synthesized successfully and the produced hexagonal nano boron nitride-added fiber laminated composite material has good absorption behavior when they are used with metallic sheets and good for isolation applications at many points in the 3–18 GHz band. Originality/value This paper will contribute to the literature on the use of basalt fabric, which are new types of fibers, and hexagonal nano boron nitride and the effects of boron nitride on radar absorption properties of composite material. It presents detail characterization of each composite by using XRD and scanning electron microscopy.

Chemical vapor deposition (CVD) typically occurs at pressures below 100 kPa because the quality of the produced film usually degrades at higher pressures. Two different approaches of CVD are presented in this study to successfully deposit thin films of copper on glass substrates at atmospheric pressure. The CVD processes occurred as a result of sublimation and thermal decomposition of Cu formate salts. The chemical composition and morphology of the deposited layers were investigated using X-ray diffraction, infrared spectroscopy, and scanning electron microscopy. The thickness of the layers was increased with a series of deposition cycles and was analysed using X-ray fluorescence spectroscopy and profilometry. The best results were obtained using Cu formate powder as the starting material and operating under a N2 atmosphere at 240 °C and 1 atm. A thickness of 600 nm was obtained after 10 deposition cycles. The resistivity values of Cu films were 2.6 × 10−7 and 8 × 10−8 Ω m after 5 and 10 cycles of deposition, respectively.

Herein the deposition and characterization of CuO films with various doping concentrations of boron through the application of the SILAR method are performed. Structural, morphological, and optical properties of the films are determined by SEM with EDS, XRD, and UV/Vis spectroscopy. EDS analysis proved the boron contributions in the films. SEM images showed that boron-doping has a decreasing effect on particle size i.e. the thickness and the length of the nanostructures decreased from 45 to 30 and from 224 to 150 nm, respectively. XRD analyses demonstrated that the crystallite size of the films increased from 12.9 to 15.9 nm with increasing boron concentration which is evidence for increased crystallinity. UV/Vis spectroscopy analysis demonstrated that band gap energy value effectively decreased by boron doping.

In this study, nanostructured Mn3O4 (manganese oxide) thin films were successfully obtained by successive ionic layer adsorption and reaction (SILAR) method on the soda lime glass substrates using Manganese Nitrate (Mn(NO3)2) and Ammonium hydroxide (NH4(OH)) as cationic and anionic precursors respectively. Structural and morphological characterizations of the Mn3O4 films obtained at different cycles were determined using X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). The crystal structure of the thin films were also confirmed by RAMAN spectroscopy. Optical properties such as absorption, transmission, reflection, extinction coefficient and optical band gap of nanostructured Mn3O4 thin films were determined by UV–Vis spectroscopy. SEM images showed that the manganese oxide nanosheets formed uniformly on substrate surface. As the deposition cycles increased, nano-sheets structure deteriorated. The optical band gap of Mn3O4 thin films varied from 2.12 to 2.59 eV, depending on the increase in number of cycles. From contact angle measurements of thin films, it was determined that thin films had hydrophilic character. © 2018, Springer Science+Business Media, LLC, part of Springer Nature.

This work reports the chemical spray synthesis of bismuth ferrite (BiFeO3, abbreviated as BFO) and tungsten-doped bismuth ferrite (W-BiFeO3, abbreviated as BWFO) nanostructured films and their nitrogen dioxide (NO2) and hydrogen (H2) gas sensor applications. The influence of tungsten-doping on the structure, morphology, surface area, and the characteristics towards NO2 and H2 gas sensing of BFO has been studied and explored and also compared with pristine BFO. The W-doping in BFO, confirmed by X-ray diffraction, energy dispersive X-ray and Fourier-transform infrared spectroscopy measurements, is proposed to explain the relative improvement in gas sensing performance between BFO and BWFO nanostructured films. At dilute concentration (100 ppm) of NO2 and H2, BWFO displays an enhanced sensitivity over BFO, which is attributed to specific changes in the morphology, structure and surface area.

Zinc oxide is an important optoelectronic material, of particular interest due to its wide band gap (Eg ~ 3.3 eV at 300 K), large exciton binding energy (~66 meV) and especially for the variety of methods by which it can be processed. Moreover, ZnO is readily able to alloy with other metals in the oxide form and has a lattice that can facilitate interstitial doping. This gives ZnO a key role in the area of optoelectronics, metal oxide thin films and thin film transistor (TFT) technologies. We demonstrate that crystalline, epitaxial-like and highly ordered ZnO thin films can be achieved from a precursor liquid at relatively low temperature via spin-coating. The synthesised films are smooth, stoichiometric ZnO with controllable thickness. An iterative layer-by-layer coating schematic is employed to demonstrate the effects of film thickness on structure, morphology as well as the surface and internal defects. Characterisation of the crystallinity, morphology, O-vacancy formation, stoichiometry, surface roughness and thickness variation was determined through X-ray diffraction, scanning and transmission electron and atomic force microscopy, X-ray photoelectron and photoluminescence spectroscopy, and the data of multi-layered ZnO correlated to defect formation and electrical conductivity. It is imperative that high crystal quality epitaxial-like thin films can be formed from solution processing to compete with physical deposition methods. We demonstrate that iterative spin-coating of deposited ZnO films results in a transition in crystal texture with increasing thickness (number of layers) from the [] m-plane to the [] c-plane. The films attain a c-axis preferential orientation, with no other crystalline peaks present. Results show that the film’s surface morphology was very smooth, with average rms roughness

ZnO, Co doped ZnO (ZnO:Co) and CoO thin films were deposited on glass substrates by using the spark discharge technique with Zn-Zn, Zn-Co and Co-Co metal electrodes (tips). The structural and optical properties of the films were characterized by X-ray diffraction, scanning electron microscopy measurements and UV-Vis spectrometry. Cubic phase reflection of CoO (200) was observed in the samples containing Co. The size of nanoparticles had varied between 38 nm and 200 nm in ZnO thin films. When Co electrode was used, spherical structure had deteriorated and clusters of particles, with smaller radii, were observed. In addition, when Co-Co electrode pairs were used, various cavities with different sizes were formed. Especially, it was observed that the optical transmittance had generally increased with the decreasing spark (charge) voltage, while increasing with the number of sparks. The Co-containing samples were green in color and it was observed that the loss of transmission appears in a specific region in the Co-doped ZnO thin films due to characteristic d-d transition of Co2+ ions. The thickness of the films had decreased with the increasing number of sparks. In addition, the band gap energy, Eg, evaluated by UV-Vis spectroscopy measurements has been shifted to higher wavelengths (red shift) for the ZnO:Co thin films.

Polycrystalline copper sulphide (CuxS) thin films were grown by ultrasonic spray pyrolysis method using aqueous solutions of copper chloride and thiourea without any complexing agent at various substrate temperatures of 240, 280, and 320 degrees C. The films were characterized for their structural, optical, and electrical properties by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive analysis of X-rays (EDAX), atomic force microscopy (AFM), contact angle (CA), optical absorption, and current-voltage (I-V) measurements. The XRD analysis showed that the films had single or mixed phase polycrystalline nature with a hexagonal covellite and cubic digenite structure. The crystalline phase of the films changed depending on the substrate temperature. The optical band gaps (E-g) of thin films were 2.07 eV (CuS), 2.50 eV (Cu1.765S), and 2.28 eV (Cu1.765S-Cu2S). AFM results indicated that the films had spherical nanosized particles well adhered to the substrate. Contact angle measurements showed that the thin films had hydrophobic nature. Hall effect measurements of all the deposited CuxS thin films demonstrated them to be of p-type conductivity, and the current-voltage (I-V) dark curves exhibited linear variation. Uludag UniversityUludag University [OUAP(F)-2013/11]; Uludag UniversityUludag University This work was supported by the Research Fund of Uludag University Project no. OUAP(F)-2013/11. The authors would like to thank Uludag University for financial support. The authors wish to thank Assoc. Professor Dr. Salih Kose of Osmangazi University (Turkey) for allowing the use of ultrasonic chemical spray pyrolysis system in semiconductor film production laboratory.

The starting temperature for SiC synthesis from elemental silicon, carbon black, and graphite powders was determined for pressures ranging from 0.8 to 11 GPa by in situ X-ray diffraction experiments. The synthesized SiC corresponds to the cubic 3C phase with the presence of stacking faults along the [111] direction. The lowest density of the stacking faults is achieved when black carbon is used instead of graphite. The minimum temperature to start the Si + C → SiC reaction slightly decreases when the pressure is increased up to 6 GPa and the reaction begins before silicon melts. For pressures higher than 8 GPa, the starting temperature increases, and the formation of SiC from the SiII phase requires the complete melting of silicon. Bulk modulus Bo= 236(14) GPa was obtained for the synthesized SiC phase. Fil: Limandri, Silvina Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina Fil: Garbarino, G.. European Synchrotron Radiation; Francia Fil: Sifre, D.. European Synchrotron Radiation; Francia Fil: Mezouar, M.. European Synchrotron Radiation; Francia Fil: Galván Josa, Víctor Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina

Cobalt doped manganese oxide thin films (Mn 3 O 4 :Co) were successfully deposited on soda lime glass substrates using SILAR technique. Mn 3 O 4 :Co thin films were characterized using XRD, SEM, Uv–VIS and Raman spectroscopy. The XRD spectra showed that thin films had substantially Hausmannite crystal structure. The preferential orientation of the pure and 0.5 at.% Co doped manganese oxide thin films (Mn 3 O 4 ) was (002), but with increasing Co doping, it was detected that this preferential orientation shift towards the (211) plane. The absorbance, transmittance and optical band gap of the Mn 3 O 4 :Co thin films were determined using Uv–Vis spectroscopy and these properties of the thin films differed considerably due to cobalt doping. The optical band gap of pure Mn 3 O 4 thin films was 2.00 eV, but on the other hand, due to the Co doping this value increased before and then decreased slightly. Optical transmittance of Mn 3 O 4 :Co films increased from 60% to 72% with the effect of Co doping. A1g mode, which is the characteristic vibration peak of Mn 3 O 4 films, was confirmed for pure and doped Mn 3 O 4 thin films at a wavelength of 658 nm. © 2019 Elsevier Ltd, MARSL.18.001, This research was supported Agri Ibrahim Cecen University Research Fund , (Project no: MARSL.18.001 ).

cited By 0; International audience; The effect of fluoride ions was investigated on the austenitic stainless steel in a typical solution of phosphoric acid that is used in industrial process, for clear understanding the damage that caused by corrosion to special alloying material Uranus B6 at temperature of 80 °C. For that the electrochemical and spectroscopy methods were used like potentiodynamic and electrochemical impedance spectroscopy, X-ray diffraction and UV–visible–IR reflection, Scanning electron microscopy and energy-dispersive spectroscopy analysis (SEM–EDX). The electrochemical methods show the drastic effect of fluoride on the passivation parameters, especially icrit, ipass and Epit caused by decreasing the alloy elements in the surface alloy, specially the molybdenum. Moreover, the spectroscopy results reflect that fluoride has two axes of interaction with the surface alloy; chemical interaction that was appeared by the dissolution mechanism, which it increases the dissolution of the base alloy atom and the alloying elements and this result was improved by the UV–visible–IR and EDX analysis. And the physical effect was demonstrated by X-ray diffraction, which is showing a deformation of the crystalline structure of surface alloy; and different pit types were detected by SEM. And the suggestion of the effect of fluoride on the nickel percent in the passive film and also on the molybdenum and copper has been proposed as a mechanism to explain these results. © 2019, Springer Nature Switzerland AG.

cited By 0; This study aims to investigate the influence of different laser surface texturing parameters on Low-Temperature Degradation and mechanical properties of Yttria-tetragonal zirconia polycrystals (3Y-TZP), focused on biomedical applications. The roughness resulted from laser irradiation was characterized by Ra, Rt, Rsk and Rku parameters, as well by SEM analysis. Wettability tests were conducted as a guide to evaluate the ability of the textures to promote osseointegration. Eleven groups of samples were created, such as five according to the laser parameters used, three correspond to the thermal treatments performed and three as different standards. After laser irradiation, all 3Y-TZP samples became black having their whiteness recovered by thermal treatments, which was measured by color analysis. X-Ray photoelectron spectroscopy was used to evaluate chemical changes, presenting the formation of zirconium sub-oxides. These results were corroborated by wettability tests, which exhibited a decrease in surface energy after thermal treatments. Mechanical strength was evaluated by B3B tests, which reveals the potential of laser irradiation combined with thermal treatments for enhancing 3Y-TZP bending resistance and reliability. LTD was accessed by XRD and reveled laser irradiation as a promising approach able to improve the resistance of 3Y-TZP to this phenomenon. © 2019 Elsevier Ltd and Techna Group S.r.l.

The present investigation focuses on the phase content of micron composite layers studied by x-ray and synchrotron diffraction. The Ti–Al 3 Ti composite has been produced by reaction sintering of titanium and aluminum foils under pressure. Sintering was finished when Al layer was fully consumed to form an intermetallic Al 3 Ti. X-ray diffraction (Bragg-Brentano geometry with a flat-plate sample) showed that composite layers basically contain only Ti and Al 3 Ti phases. Synchrotron diffraction allowed to reveal the presence of residuals of Al phase. Diffraction experiments were performed at the SR beamline №4 of the VEPP-3 storage ring. The frame capture mode with the use of the synchrotron beam, 0.4×0.1 mm, allowed proving the absence of Al 2 O 3 phase particles along the Ti/Al 3 Ti interfaces.

International audience; Bismuth(III) oxide is included as a radio-opacifier in dental materials, including hydraulic silicate cements, the material of choice for several endodontic procedures. It has been implicated in tooth discoloration after contact with endodontic irrigants, in particular NaOCl solution, To date, there has been no work on the chemistry: all reports have been of clinical findings only. The purpose now was to report the reactions leading to colour change from Bi2O3 in contact with solutions used in routine endodontic practice. Ten-gram portions of Bi2O3 were immersed in either water, NaOH, NaCl, NaOCl or HCl solution, either in the dark or exposed to visible light, and samples retrieved at 1, 4, 12 and 24 weeks. After washing, these were exposed to either added CO2 or not, for 1 week while drying, and under the same dark or light conditions. Changes in appearance were monitored by photography and colour measurement, and chemically by X-ray diffraction and Fourier-transform infrared spectroscopy. 24-week material was studied using electron paramagnetic resonance and Raman spectroscopy; NaOCl-treated material was also examined by scanning electron microscopy. With water, NaCl and NaOH, bismuth subcarbonate was formed. With or without added carbon dioxide, discoloration occurred from pale yellow to light brown when exposed to light, and to a lesser extent in the dark, intensifying with time. In contrast, exposure to NaOCl rapidly formed a dark brown-black sodium bismuthate. With HCl, white BiOCl was formed. Bi2O3 is not at all inert in this context as is commonly believed, denying its principle of use. Previously unreported solution-mediated reaction occurs readily even in water and NaCl solution, forming new compounds that discolour. In contact with NaOCl sodium bismuthate is formed; severe darkening occurs rapidly. The reactivity is such that Bi2O3 is not indicated for dental materials and should be withdrawn from use. © 2020 Camilleri et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

The facile, rapid and bulk production of composite materials consisting of carbon nanostructures doped with metal-based compounds has been a significant challenge for various research areas where such types of materials can be applied, including catalysis, energy storage and water purification. In this work, a carbon foam‑aluminum fluoride composite (C-AlF3) was developed by adopting a combustion synthesis approach, which is an attractive alternative to wet chemical methods usually employed for such purposes. The flame ignition and combustion of a solid-state mixture comprising a fluoropolymer and nano-sized Al powder leads to the formation of a porous carbon foam network doped with dispersed cubic-like AlF3 nanoparticles (100 to 500 nm in size), as observed by high-resolution microscopy methods. Selective area electron diffraction and X-ray diffraction studies revealed a rhombohedral α-AlF3 crystal structure for these embedded particles, while micro-Raman spectroscopy indicated typical carbonaceous features for the foamy matrix. The C-AlF3 composite also showed a combination of micro-, meso- and macro-porous characteristics (i.e. pore sizes in the nanometer scale) based on the analysis of N2 sorption data collected at 77 K. The findings of this study provide useful insights for further research on carbon-based nanocomposite materials prepared via direct combustion synthesis routes. Keywords: Nanocomposite, Porous material, Carbon foam, Aluminum fluoride, Combustion synthesis

The cubic (c) and monoclinic (m) polymorphs of Gd2O3 were studied using the combined analysis of several materials science techniques - X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and photoluminescence (PL) spectroscopy. Density functional theory (DFT) based calculations for the samples under study were performed as well. The cubic phase of gadolinium oxide (c-Gd2O3) synthesized using a precipitation method exhibits spheroidal-like nanoclusters with well-defined edges assembled from primary nanoparticles with an average size of 50 nm, whereas the monoclinic phase of gadolinium oxide (m-Gd2O3) deposited using explosive pyrolysis has a denser structure compared with natural gadolinia. This phase also has a structure composed of three-dimensional complex agglomerates without clear-edged boundaries that are ~21 nm in size plus a cubic phase admixture of only 2 at. % composed of primary edge-boundary nanoparticles ~15 nm in size. These atomic features appear in the electronic structure as different defects ([Gd...O-OH] and [Gd...O-O]) and have dissimilar contributions to the charge-transfer processes among the appropriate electronic states with ambiguous contributions in the Gd 5p - O 2s core-like levels in the valence band structures. The origin of [Gd...O-OH] defects found by XPS was well-supported by PL analysis. The electronic and atomic structures of the synthesized gadolinias calculated using DFT were compared and discussed on the basis of the well-known joint OKT-van der Laan model, and good agreement was established., 27 pages, 10 figures, accepted in Appl. Surf. Sci

We report on a kerfless exfoliation approach to further reduce the costs of crystalline silicon photovoltaics making use of evaporated Al as a double functional layer. The Al serves as the stress inducing element to drive the exfoliation process and can be maintained as a rear contacting layer in the solar cell after exfoliation. The 50-70 μm thick exfoliated Si layers show effective minority carrier lifetimes around 180 μs with diffusion lengths of 10 times the layer thickness. We analyze the thermo-mechanical properties of the Al layer by x-ray diffraction analysis and investigate its influence on the exfoliation process. We evaluate the approach for the implementation into solar cell production by determining processing limits and estimating cost advantages of a possible solar cell design route. The Al-Si bilayers are mechanically stable under processing conditions and exhibit a moderate cost savings potential of 3-36% compared to other c-Si cell concepts. © Materials Research Society 2015.

The heavy metal content in fly ash from biomass combustion, such as straw, wood and sludge, often needs reducing before the ash can be used as fertilizer for agricultural land or as a component in the production of construction materials. In this study, fly ash from a boiler fueled with wood chips and straw was treated either by electrodialytic remediation (EDR) directly or by a combination of EDR and pre-wash with distilled water to investigate the possibilities of reducing the heavy metal content and reusing nutrients as fertilizer and bulk material in construction materials. Different experimental set-ups were tested for EDR treatment primarily of Cd and Pb as well as of Cu and Zn. Elemental contents such as K, P and Ni were compared in ash samples before and after treatment. The results showed that pre-washing caused an increase in total concentrations of most heavy metals because the highly soluble fraction, mainly KCl and K 2 SO 4 , was removed. After EDR treatment, the Cd concentration was reduced to below 2 mg kg −1 in all ash samples with high and stable average removal of above 95%, no matter how high the initial concentration was. The amount of Pb removed varied from 12% to 67%. Even though Pb was extracted from the ash samples, its concentrations in the treated ash samples were elevated due to the ash dissolution, except in the case of pre-washed ash treated in a two-compartment EDR cell, where the mass of Pb removed was the highest with a final concentration of about 100 mg kg −1 . The two-compartment EDR cell probably performed better due to a fast acidification process. In addition, this process was less energy-consuming. However, the fast acidification did in turn affect the leaching property of the treated ash, such as As and Ni, exceeding the limiting concentrations. The EDR/pre-wash-EDR treated ash mainly contained quartz, and the X-ray diffraction (XRD) peaks of K salts had disappeared. This shows that the potassium fertilizer potential was lost in the treated ashes, but the quartz mineral is beneficial in construction materials, such as ceramics. The K fertilizer could be recovered from the water after pre-washing and also from the catholyte through chemical operations, including a separation step.

Zinc oxide (ZnO) nanostructures find applications in optoelectronic devices, photo voltaic displays and sensors. In this work zinc oxide nanostructures in different forms like nanorods, tripods and tetrapods have been synthesized by thermal evaporation of zinc metal and subsequent deposition on a glass substrate by vapor transport in the presence of oxygen. It is a comparatively simpler and environment friendly technique for the preparation of thin films. The structure, morphology and optical properties of the synthesized nanostructured thin film were characterized in detail by using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and photoluminescence (PL). The film exhibited bluish white emission with Commission International dEclairage (CIE) coordinates x = 0.22, y = 0.31. (C) 2015 Elsevier Ltd. All rights reserved.

Three new dimethyl aluminium complexes 1-3 containing aminophenol ligands (LAlMe2, where L1 = diethylaminophenoxide, L2 = diisopropylaminophenoxide and L3 = piperidinophenoxide) were synthesized and characterized by different spectroscopic techniques and elemental analysis. The solid state structure of 1 was determined by single crystal X-ray diffraction studies. The data revealed that 1 possesses as a distorted tetrahedral geometry around the aluminium centre. The catalytic activities of these complexes towards the ring opening polymerization (ROP) of rac-lactide (rac-LA) and L-lactide (L-LA) were examined and good efficiency with controlled number average molecular weight (Mn) and narrow molecular weight distributions (MWDs) were achieved. Homonuclear decoupled 1H NMR spectrum confirms the heterotactic enrichment in the PLA obtained from rac-LA. The MALDI-TOF mass and 1H NMR spectra of low molecular weight oligomers revealed that the aminophenoxide ligand initiates the ROP. The geometries of all the complexes were optimized at B3LYP/LANL2DZ level and DFT calculations were carried out in order to establish the relation between the reactivity and the HOMO-LUMO energy gap. � 2015, Elsevier Ltd. All rights reserved.

WOS: 000371608500003 PubMed ID: 26142459 In this study, the thermoluminescence (TL) characteristics of undoped and various Ce3+-doped Zn(BO2)(2) powder samples excited by beta irradiation are reported for the inot signrst time. Zn(BO2)(2):Ce3+ powder samples were prepared by the nitric acid method (NAM) using the starting oxides [zinc oxide (ZnO), boric acid (H3BO3) and doped element oxide (CeO2)]. The formations of the obtained samples were confirmed by an X-ray diffraction study. Dose responses of Ce3+-doped Zn(BO2)(2) samples were investigated after the beta irradiation in the dose range from 143 mGy to 60 Gy. All TL measurements were made on using an automated Riso TL/OSL DA-20 reader. TL emission was detected through a filter pack (Schott BG-39 and Corning 7-59) transmitting between 330 and 480 nm. TL glow curves were obtained using a constant heating rate of 5A degrees C s(-1) from room temperature (RT) to 450A degrees C in an N-2 atmosphere. The dose response and minimum detectable dose (MDD) values of the samples were determined. The dose responses of all the samples tested exhibited a superlinear behaviour. MDD value of 4 % Ce3+-doped Zn(BO2)(2) sample, which shows a high temperature peak at about 230A degrees C, was determined as 96 mGy. MDD values for 1, 2, 3, 5 and 10 % Ce3+-doped Zn(BO2)(2) samples were also determined as 682, 501, 635, 320 and 824 mGy, respectively. The trap parameters of undoped and 4 % Ce3+-doped Zn(BO2)(2) samples were estimated by the computerised glow curve deconvolution method.

A series of magnesium complexes containing the tetradentate di and tri anionic amine phenolate backbone were synthesized from the reaction of suitable ligands and diethyl magnesium. All the complexes were completely characterized by different spectroscopic techniques and single crystal X-ray diffraction studies. The single crystal X-ray structure showed that complexes 1 and 5 are dinuclear and trinuclear respectively. All these complexes (1-8) were found to be active towards the bulk the ring opening polymerization (ROP) of lactides in the presence or absence of benzyl alcohol, at 140 �C and it was found that the polymerizations were better controlled in the presence of benzyl alcohol. The kinetics and mechanistic studies associated with these polymerizations have been performed. The complexes have been shown to be highly active toward the copolymerization of cyclohexene oxide (CHO) and propylene oxide (PO) with carbon dioxide. The introduction of a bulky ortho substituent on the phenoxy units of the ligand decreases the catalytic activity of the corresponding magnesium complexes. � 2015 Elsevier Ltd. All rights reserved.

Al-substituted α-type nickel hydroxides (α-Ni(OH)2) containing different interlayer anions ( NO 3 − , SO 4 2 − , Cl−, CO 3 2 − , OH−) are synthesized via a polyacrylamide (PAM) assisted two-step drying method. The effects of interlayer anions on the microstructure, morphology and electrochemical performance of Al-substituted α-Ni(OH)2 are investigated by X-ray diffraction (XRD), infrared spectroscopy (IR), scanning electron microscope (SEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and charge/discharge tests. The results demonstrate that the intercalated anions have a critical effect on the basal plane spacing, degree of crystallinity, and electrochemical properties of the end products. Especially, the intercalated anions have a marked impact on the activation process of the nickel electrodes. The Cl− intercalated α-Ni(OH)2 sample exhibits better high-rate discharge ability and cycle stability than samples with other interlayer anions. This is attributed to the higher crystallinity, better exchange ability and smaller anion size of Cl−. The anion exchange ability and the size of anions also play an important role in the proton diffusion rate, which directly affects the electrochemical properties of α-Ni(OH)2. The relationships between the specific capacity and basal spacing are also discussed in details for the five samples.

In this work we investigate two alternative methods to remove amine molecules from as-synthesized vanadium oxide nanotubes (VONTs). Thermal treatment results in the formation of polycrystalline nanorods (poly-NRs) and ion exchange reactions with NaCl result in the formation of Na-VONTs. The removal of amine molecules is confirmed by monitoring the inorganic and organic phase changes and decomposition, respectively, using electron microscopy, IR spectroscopy and X-ray diffraction analyses. We compare the electrochemical performance of as-synthesized VONTs, poly-NRs and Na-VONTs. This work demonstrates that the presence of amine molecules within the layers of vanadium oxide impedes the intercalation of lithium ions, and that their removal results in a significant improvement in electrochemical characteristics. Out of the three vanadium oxide nanostructures investigated, poly- NRs exhibit the most promising results for practical use as a cathode material.

A plethora of magnesium compounds containing imino(phenoxide) (1-4) and bis(imino)phenoxide (5-10) ligand backbone have been synthesized via the reaction of diethyl magnesium with two equivalent of the corresponding ligand. These compounds were completely characterized by different spectroscopic techniques and elemental analyses. The monomeric nature of the magnesium complexes 3, 5, 6, 9, and 10 were further confirmed by single crystal X-ray diffraction studies. The magnesium centers posses distorted trigonal bipyramidal geometry. The controlled hydrolysis compound Mg7O8 (C22H28NO2)6 (11) was adequately characterized using 1H, 13C NMR, ESI-MS, and the biscubane structure was further confirmed by single crystal X-ray diffraction studies. The Mg7O8 core is deeply embedded with the ligand periphery. These compounds (1-10) were found to be active towards the bulk ring opening polymerization (ROP) of lactides, yielding polymers with high number average molecular weight (Mn) and controlled molecular weight distributions (MWDs). In addition, these compounds have been shown to be highly active toward the copolymerization of carbon dioxide with cyclohexene oxide and styrene oxide. � 2015 Wiley Periodicals, Inc. J. Polym. Sci.

Two new water-soluble copper(II) complexes, [Cu(dmphen)(2)(NO3)]NO3 (1), [Cu(dmphen)(tyr)(H2O)] NO3 center dot H2O (2) and the diquartemary salt of dmphen (dmphen = 4,7-dimethyl-1,10-phenanthroline and tyr = L-tyrosine), have been synthesized and characterized by elemental analysis, H-1 NMR, C-13 NMR and IR spectroscopy, thermal analysis and single crystal X-ray diffraction techniques. The CT-DNA binding properties of these compounds have been investigated by absorption, emission spectroscopy and thermal denaturation measurements. The supercoiled pBR322 plasmid DNA cleavage activity of these compounds has been explored by agarose gel electrophoresis. The cytotoxicity of these compounds against MCF-7, Caco-2, A549 cancer cells and BEAS-2B healthy cells was also studied by the XTT method. Complexes 1 and 2 exhibit significant cytotoxicity, with lower IC50 values than those of cisplatin.

SiGe thin films were deposited on glass and PET substrate by the thermionic vacuum arc (TVA) method for the first time. TVA is an anodic plasma generator which works in high vacuum conditions. Highly pure and quality films can be deposited on different substrates by means of this method. In order to characterize the produced films, X-ray diffraction, field emission scanning electron microscope (FESEM), atomic force microscope (AFM), energy dispersive X-ray spectrometer (EDX), optical tensiometer, UV-Vis spectrophotometer and spectroscopic ellipsometer (SE) devices were used. The obtained XRD peaks at 47° and 75° are described to the reflections of (220) and (331) planes of Ge or Si. According to the measurement results, substrates materials are affect the surface and optical properties of the deposited SiGe layers. SiGe coated samples with low optical band gaps exhibit low transparency and high absorption. The structures are homogenous and less rough. Copyright © 2015 American Scientific Publishers All rights reserved.

Microstructural characterization of alloy 718 fusion zone welded with both solid solution and age hardenable filler metal has been done. The microsegregation and the aging response were studied by employing three levels of weld cooling rate. Gas Tungsten Arc welding process was used. The fusion zone of solid solution filler metal has been responding to the aging treatment due to the weld process conditions and weld metal chemistry. However the weld metal composition was modified due to the higher molybdenum (Mo) content in solid solution filler metal. The effect of this modification on the phase reaction temperatures was studied and the same was compared with the conventional filler metal. � 2014 Elsevier Inc.

High-density Al-substituted α-nickel hydroxide with interlayer NO3− for alkaline nickel-based rechargeable batteries has been synthesized using a polyacrylamide (PAM) assisted two-step drying method. In order to improve its electrochemical performance, Al-substituted α-Ni(OH)2 with interlayer NO3− is modified by a simple anion exchange method using NaCl solution. The physical and electrochemical properties of the synthesized material are characterized by means of X-ray diffraction (XRD), infrared spectroscopy (IR), scanning electron microscopy (SEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and a charge–discharge test. Compared with NO3− intercalated α-Ni(OH)2 precursor, the resulting Cl− intercalated α-Ni(OH)2 samples possess more excellent electrochemical activities, including higher proton diffuse coefficient, lower electrochemical impedance, higher specific capacity, and better cyclic stability. Especially, it is also found that the introduction of Cl− can greatly accelerate the activation process of α-Ni(OH)2 electrodes.

Electroless nickel (EN) plating was performed on arc discharge synthesized multiwalled carbon nanotubes for various deposition times. X-ray diffraction (XRD), Transmission electron microscopy (TEM), and Raman spectroscopy characterization techniques are used to identify the presence of nickel deposition on the carbon nanotubes (CNTs) and the degree of graphitization. The results indicate that impurities are less in the purified CNTs as compared to raw carbon soot. Increasing deposition time up to 60 min increases uniform deposition of nickel throughout the length of the CNTs. However, for deposition time longer than 60 min, nickel particles are seen separated from the surface of the CNTs. Uniformly coated nickel CNTs throughout their length are potential candidates for reinforcements in composite materials. Magnetic properties of the nickel coated CNTs, with deposition time of 30 and 60 min were also evaluated. The magnetic saturation of nickel coated CNTs with deposition time of 30 min is less compared to nickel coated CNTs with deposition time of 60 min. � 2014 Elsevier B.V. All rights reserved.

Metallic osmium (Os) is one of the most exceptional elemental materials, having, at ambient pressure, the highest known density and one of the highest cohesive energies and melting temperatures. It is also very incompressible, but its high-pressure behaviour is not well understood because it has been studied so far only at pressures below 75 gigapascals. Here we report powder X-ray diffraction measurements on Os at multi-megabar pressures using both conventional and double-stage diamond anvil cells, with accurate pressure determination ensured by first obtaining self-consistent equations of state of gold, platinum, and tungsten in static experiments up to 500 gigapascals. These measurements allow us to show that Os retains its hexagonal close-packed structure upon compression to over 770 gigapascals. But although its molar volume monotonically decreases with pressure, the unit cell parameter ratio of Os exhibits anomalies at approximately 150 gigapascals and 440 gigapascals. Dynamical mean-field theory calculations suggest that the former anomaly is a signature of the topological change of the Fermi surface for valence electrons. However, the anomaly at 440 gigapascals might be related to an electronic transition associated with pressure-induced interactions between core electrons. The ability to affect the core electrons under static high-pressure experimental conditions, even for incompressible metals such as Os, opens up opportunities to search for new states of matter under extreme compression. © 2015 Macmillan Publishers Limited. DE-FG02-94ER14466; EAR-1128799; U.S. Department of Energy, USDOE; Office of Science, SC; Argonne National Laboratory, ANL: DE-AC02-06CH11357; Association Française contre les Myopathies, AFM; European Research Council, ERC: 338957 FEMTO/NANO; Deutsche Forschungsgemeinschaft, DFG; Bundesministerium für Bildung und Forschung, BMBF: 10-0026, 5K13WC3, DU 954-8/1, O5K2013; Nederlandse Organisatie voor Wetenschappelijk Onderzoek, NWO; Ministry of Education and Science of the Russian Federation, Minobrnauka; Vetenskapsrådet, VR: 621-2011-4426; Science and Engineering Research Council, SERC Acknowledgements L.D. and N.D. acknowledge financial support from the Deutsche Forschungsgemeinschaft (DFG) and the Federal Ministry of Education and Research (BMBF), Germany. N.D. thanks the DFG for funding through the Heisenberg Program and the DFG project number DU 954-8/1, and the BMBF for grant number 5K13WC3 (Verbundprojekt O5K2013, Teilprojekt 2, PT-DESY). M.E., Q.F., and I.A.A. acknowledge supportfromthe SwedishFoundationforStrategicResearchprogramme SRL grant numbers 10-0026, the Swedish Research Council (VR) grant numbers 621-2011-4426, the Swedish Government Strategic Research Area Grant Swedish e-Science Research Centre (SeRC), and in Materials Science “Advanced Functional Materials” (AFM). The work was supported by the Ministry of Education and Science of the Russian Federation (grant number 14.Y26.31.0005). The simulations were carried out using supercomputer resources provided by the Swedish national infrastructure for computing (SNIC). M.I.K. acknowledges financial support from the ERC Advanced grant number 338957 FEMTO/NANO and from NWO via a Spinoza Prize. Portions of this work were performed at GeoSoilEnviroCARS (Sector 13), Advanced Photon Source (APS), Argonne National Laboratory. GeoSoilEnviroCARS is supported by the National Science Foundation - Earth Sciences (EAR-1128799) and Department of Energy - GeoSciences (DE-FG02-94ER14466). This research used resources of the Advanced Photon Source, a US Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under contract number DE-AC02-06CH11357.

Length-change measurements of 1·4 nm tobermorite, jennite and calcium silicate hydrate preparations (with varying calcium/silicon ratio) subjected to drying from the 11% relative humidity condition are reported. The dimensional stability investigation is focused on the role of adsorbed and interlayer water as shrinkage mechanisms involving menisci effects in capillary pores are eliminated in this humidity range. Length change against mass loss curves and the corresponding d002 basal spacing change (obtained by X-ray diffraction) with mass loss are assessed and inferences drawn regarding nanostructural models for calcium silicate hydrates in hydrated Portland cement paste. Length changes of the pure phases were significantly greater than those for hydrated cement paste due to the restraining effect of unhydrated cement particles and calcium hydroxide crystals in the paste. The dimensional stability and the role of the removal of ‘structural water' from the systems studied are discussed in terms of its relevance to cement-based materials.

For Li-air batteries to reach their full potential as energy storage system, a complete understanding of the conditions and reactions in the battery during operation is needed. To follow the reactions in situ a capillary-based Li-O2 battery has been developed for synchrotron-based in situ X-ray powder diffraction (XRPD). In this article, we present the results for the analysis of 1st and 2nd deep discharge and charge for a cathode being cycled between 2 and 4.6 V. The crystalline precipitation of Li2O2 only is observed in the capillary battery. However, there are indications of side reactions. The Li2O2 diffraction peaks grow with the same rate during charge and the development of the full width at half maximum (FWHM) is hkl dependent. The difference in the FWHM of the 100 and the 102 reflections indicate anisotropic morphology of the Li2O2 crystallites or defects along the c-axis. The effect of constant exposure of X-ray radiation to the electrolyte and cathode during charge of the battery was also investigated. X-ray exposure during charge leads to changes in the development of the intensity and the FWHM of the Li2O2 diffraction peaks. The X-ray diffraction results are supported by ex situ X-ray photoelectron spectroscopy (XPS) of discharged cathodes to illuminate non-crystalline deposited materials.

International audience; Synopsis-A new ternary scheelite tungstate (Sr,Ce)WO 4 phase was synthesized, with a 2D incommensurately modulated structure linked to partial ordering of Sr, Ce cations and vacancies as was evidenced by high resolution electron microscopy. The bang gap of 3.2 eV makes it a promising violet emitting compound. Abstract-type the Abstract here (Style: IUCr Abstract) For the first time, a ternary tetragonal scheelite structure tungstate with strontium and cerium cations,(Sr,Ce)WO 4 , was synthesized. As much as 35 % Ce could be inserted in the structure, leaving 1/7 of the (Sr,Ce) cation sites vacant. Partial ordering of Sr and Ce, with atomic displacements, were evidenced by high resolution electron microscopy. 2D incommensurate modulations occur in this material, in small domains 20 nm in size. The band gap of this compound is significantly lower than the band gap of SrWO 4 and this was related to the distortions of WO 4 and (Sr,Ce)O 8 polyhedra. The bang gap value of 3.2 eV makes Sr 1/2 Ce 5/14 □ 1/7 WO 4 a promising candidate for violet luminescence.

Copper indium gallium diselenide (CuIn x Ga 1 − x Se 2 ) thin films were grown on indium tin oxide coated glass substrate by a sequential electrodeposition technique. The deposition bath consisted of an aqueous solution of 10 mM CuCl 2 , 10 mM InCl 3 , 20 mM GaCl 3 , 20 mM H 2 SeO 3 as precursors, and 200 mM LiCl. The pH of the solution was adjusted to 1.7 by adding HCl. Cu, In, Cu, Ga, Cu, Se components were deposited sequentially. Cu/In/Cu/Ga/Cu/Se stacked layers were annealed at 250, 350, 450 and 550 °C for 30 min. X-ray diffraction (XRD) studies showed the produced CIGS thin films had polycrystalline structure. From scanning electron microscopy studies, it was found that CIGS thin films exhibited different surface appearances depending on annealing temperature. Energy dispersive x-rays analysis showed that elemental ratio of Se decreased from 46.99 to 14.84 (%) with increasing of annealing temperature. Optical band gap of the CIGS films varied between 1.41 and 2.19 eV. Thicknesses and refractive indices of the produced CIGS thin films were calculated by fitting spectroscopic ellipsometric data (ψ and ∆) by using Cauchy model. Deposited CIGS thin films were p-type semiconductor with carrier concentration of ~ 10 16 cm − 3 .

Several ZnBO powder samples having dopants concentrations of 0.1, 0.01, 0.04 wt% Ce and La were prepared using the nitric acid method via the starting oxides. Several complementary methods such as powder X-ray diffraction (XRD), thermal analyses environmental scanning electron microscopy (ESEM), Radioluminescence (RL) and Cathodoluminescence (CL) techniques were used. Unique luminescence properties of Ce doped ZnBO powder samples are reported for the first time. A new luminescence bands appearing in red part of the spectrum and having all the characteristics of Ce were obtained from RL results. Changing the Ce and La concentration of 0.01–0.1 wt% leads to an increase in RL and CL intensities of Ce and La ions and also CL emission spectra of ZnBO show gradual shift towards longer wavelength. When we compare the luminescence intensity of the samples it is seen that Ce doped ZnBO has the highest intense whereas La doped ZnBO has the lowest one. However, emission spectra of both Ce and La doped samples kept unchanged.

BaFe 0.9-x Y 0.1 Co x O 3-δ (0 ≤ x ≤ 0.15) is shown to adopt the cubic perovskite structure at temperatures up to 1400 K in air. The oxygen vacancy concentration increases with both cobalt content and temperature, with BaFe 0.75 Y 0.1 Co 0.15 O 2.35 being the most oxygen-deficient composition observed. At 700 K the conductivity is ∼2 S cm −1 across the whole composition range. Measurements of the Seebeck coefficient show that holes are the dominant carrier. The coefficient of thermal expansion is essentially constant above 800 K, but not at lower temperatures. Chemical reactivity tests, along with the coefficient of expansion, show that these perovskites would not be suitable electrodes for fuel cells with fluorite electrolytes but they might serve as permeable membranes in catalytic reactors.

Tuning the band-gap of graphene is a current need for real device applications. Copper (Cu) as a substrate plays a crucial role in graphene deposition. Here we report the fabrication of in-situ nitrogen (N) doped graphene via chemical vapor deposition (CVD) technique and the effect of Cu substrate thickness on the growth mechanism. The ratio of intensities of G and D peaks was used to evaluate the defect concentration based on local activation model associated with the distortion of the crystal lattice due to incorporation of nitrogen atoms into graphene lattice. The results suggest that Cu substrate of 20 µm in thickness exhibits higher defect density (1.86×10 12 cm −2 ) as compared to both 10 and 25 µm thick substrates (1.23×10 12 cm −2 and 3.09×10 11 cm −2 , respectively). Furthermore, High Resolution -X-ray Photoelectron Spectroscopy (HR-XPS) precisely affirms ~0.4 at% of nitrogen intercalations in graphene. Our results show that the substitutional type of nitrogen doping dominates over the pyridinic configuration. In addition, X-ray diffraction (XRD) shows all the XRD peaks associated with carbon. However, the peak at ~24° is suppressed by the substrate peaks (Cu). These results suggest that nitrogen atoms can be efficiently incorporated into the graphene using thinner copper substrates, rather than the standard 25 µm ones. This is important for tailoring the properties by graphene required for microelectronic applications.

The CuxNi1−xFe2O4 (x = 0.0, 0.2, 0.5, 0.8, 1.0) nanoferrite powder were synthesized through chemical co-precipitation method using only (FeCl3, 6H2O), (NiCl2, 6H2O), (CuCl2, 4H2O), NaOH and acid oleic as raw materials. The synthesized powder was characterized by X-ray diffraction (XRD); it was used to determine the structural properties. The transmission electron microscopy and the scanning electron microscopy were used to determine the morphology and particle size. The Fourier Transform Infra-Red (FT-IR) spectroscopy is used to deduce the structural investigation and confirmation of ferrite. Raman spectroscopy is used to verify that we have synthesized CuxNi1−xFe2O4 and determines their phonon modes. The thermo gravimetric analysis findings allow the thermal cycle determination of samples whereas differential thermal analysis findings allow the phase transition temperature identification. The optical study UV–Visible is used to calculate the band gap energies. The vibrating sample magnetometer was used to obtain the hysteresis parameters. In conclude, the XRD confirmed the single phase spinel structure. The lattice constant increased with the increased copper contents. The size of nanoparticles decreased with the increased copper contents. The magnetic property of the CuxNi1−xFe2O4 shows remarkable changes with change of Cu2+.The variation of copper substitution has a significant influence on the optical, grain size and magnetic properties. The mean crystalline size of the synthesized ferrite was in the range of 14–43 nm., The present work was supported by the Research Funds of Electrochemistry, Materials and Environment Research Unit UREME (UR17ES45), Faculty of Sciences Gabes University, Tunisia and Structures, Properties and Modeling of Solids (SPMS) Laboratory, Ecole Centrale Paris, France.

Although cobalt-based heterogeneous catalysts are the central focus in water oxidation research, interest in copper-based water oxidation catalysts has been growing thanks the great abundance of copper and its biological relevance. Several copper oxides have recently been reported to be active catalysts for water oxidation. In this study, a heterogeneous copper-based water oxidation catalyst that is not an oxide has been reported for the first time. Single-crystal XRD studies indicate that the compound is a one-dimensional coordination compound incorporating copper paddle-wheel units connected through phosphine dioxide ligands. The catalyst exhibits an onset potential of 372 mV at pH 10.2, whereas an overpotential of only 563 mV is required to produce a current density of 1 mA cm−2. In addition to cyclic voltammetric and chronoamperometric studies, an investigation into the effect of pH on the catalytic activity and the robustness of the catalyst using long-term bulk electrolysis (12 h) is presented.

Since 2011 the JET tokamak has been operated with a metal ITER-like wall (JET-ILW) including castellated beryllium limiters and lamellae-type bulk tungsten tiles in the divertor. This has allowed for a large scale test of castellated plasma-facing components (PFC). Procedures for sectioning the limiters into single blocks of castellation have been developed. This facilitated morphology studies of morphology of surfaces inside the grooves for limiters after experimental campaigns 2011–2012 and 2013–2014. The deposition in the 0.4–0.5mm wide grooves of the castellation is ‘shallow’. It reaches 1–2mm into the 12mm deep gap. Deuterium concentrations are small (mostly below 1 × 1018 cm−2 ). The estimated total amount of deuterium in all the castellated limiters does not exceed the inventory of the plasma-facing surfaces (PFS) of the limiters. There are only traces of Ni, Cr and Fe deposited in the castellation gaps. The same applies to the carbon content. Also low deposition of D, Be and C has been measured on the sides of the bulk tungsten lamellae pieces. Modelling clearly reflects: (a) a sharp decrease in the measured deposition profiles and (b) an increase in deposition with the gap width. Both experimental and modelling data give a strong indication and information to ITER that narrow gaps in the castellated PFC are essential. X-ray diffraction on PFS has clearly shown two distinct composition patterns: Be with an admixture of Be–W intermetallic compounds (e.g. Be22W) in the deposition zone, whilst only pure Be has been detected in the erosion zone. The lack of compound formation in the erosion zone indicates that no distinct changes in the thermo-mechanical properties of the Be PFC might be expected. EURATOM 633053 Swedish Research Council (VR) 2015–04844

Titanium–tantalum based alloys can demonstrate a martensitic transformation well above 100 °C, which makes them attractive for shape memory applications at elevated temperatures. In addition, they provide for good workability and contain only reasonably priced constituents. The current study presents results from functional fatigue experiments on a binary Ti–25Ta high-temperature shape memory alloy. This material shows a martensitic transformation at about 350 °C along with a transformation strain of 2 pct at a bias stress of 100 MPa. The success of most of the envisaged applications will, however, hinge on the microstructural stability under thermomechanical loading. Thus, light and electron optical microscopy as well X-ray diffraction were used to uncover the mechanisms that dominate functional degradation in different temperature regimes. It is demonstrated the maximum test temperature is the key parameter that governs functional degradation in the thermomechanical fatigue tests. Specifically, ω-phase formation and local decomposition in Ti-rich and Ta-rich areas dominate when T max does not exceed ≈430 °C. As T max is increased, the detrimental phases start to dissolve and functional fatigue can be suppressed. However, when T max reaches ≈620 °C, structural fatigue sets in, and fatigue life is again deteriorated by oxygen-induced crack formation. Copyright © Materials Research Society 2017

New copper(II) complexes-dimeric-[Cu(nphen)(gly)(H2O)](+) (1) and [Cu(dmphen)(gly)(NO3)(H2O)] (2) (nphen = 5-nitro-1,10-phenanthroline, dmphen = 4,7-dimethyl-1,10-phenanthroline, and gly = glycine)-have been synthesized and characterized by CHN analysis, single-crystal X-ray diffraction techniques, FTIR, EPR spectroscopy, and cyclic voltammetry. The CT-DNA-binding properties of these complexes have been investigated by thermal denaturation measurements and both absorption and emission spectroscopy. The DNA cleavage activity of these complexes has been studied on supercoiled pUC19 plasmid DNA by gel electrophoresis experiments in the absence and presence of H2O2. Furthermore, the interaction of these complexes with bovine serum albumin (BSA) has been investigated using absorption and emission spectroscopy. The thermodynamic parameters, free-energy change (Delta G), enthalpy change (Delta H), and entropy change (Delta S) for BSA + complexes 1 and 2 systems have been calculated by the van't Hoff equation at three different temperatures (293.2, 303.2, and 310.2 K). The distance between the BSA and these complexes has been determined using fluorescence resonance energy transfer (FRET). Conformational changes of BSA have been observed using the synchronous fluorescence technique. In addition, in vitro cytotoxicities of these complexes on tumor cell lines (Caco-2, A549, and MCF-7) and healthy cells (BEAS-2B) have been examined. The antimicrobial activity of the complexes has also been tested on certain bacteria cells. The effect of mono and dimeric in the above complexes is presented and discussed. New copper(II) complexes-dimeric-[Cu(nphen)(gly)(H2O)](+) (1) and [Cu(dmphen)(gly) (NO3)(H2O)] (2) (nphen = 5-nitro-1,10-phenanthroline, dmphen = 4,7-dimethyl-1,10-phenanthroline and gly = glycine)-have been synthesized and characterized by CHN analysis, single-crystal X-ray diffraction techniques, FTIR and EPR spectroscopy. They have been tested for their in vitro DNA/BSA interactions by the spectroscopic methods. These complexes exhibited higher cytotoxic and antimicrobial activities. Complex 1 shows better DNA / BSA interactions in comparison to complex 2.

Self-assembly of four components has resulted into the formation of M 2L2 type dinuclear metallacyclophanes [Re(CO) 3Br(?-L)]2 (1-5), using flexible ester functionalised organic spacers and metal precursor containing fac-Re(CO)3 corners. The dinuclear metallacyclophanes were synthesized from ReBr(CO)5 and ditopic pyridyl ligands (L) (L = etdp, prdp, budp, pedp and hedp). The self-assembled compounds 1-5 were characterised by elemental analysis, IR, NMR, absorption and emission spectroscopic techniques. Molecular structure of 1 and 2 have been characterised by single crystal X-ray diffraction methods and the molecular masses of 3-5 were evaluated by ESI-MS. Cytotoxicity studies of metallacyclophanes 1, 3 and 5 on six different cancer and normal cells revealed that the metallacyclophanes selectively inhibit certain cancer cells. Especially, compound 5 showed broad-spectrum inhibitory activities in five cancer cells tested with low IC50 value comparable to a reference compound (cisplatin). The anticancer activity of compound 5 is attributed to the induction of early apoptosis. Hence, this class of compounds forms potential anticancer agents. � 2014 Elsevier B.V. All rights reserved.

This work is an experimental study on the formation, characteristics and properties of electroless nickel phosphorous (Ni-P) coatings and electroless nickel alumina (Ni-P-Al2O3) coating with varying reducing agent concentration. The results obtained indicate that the deposition rate and surface roughness of both Ni-P coating and Ni-P-Al2O3 coatings are highly influenced by reducing agent (sodium hypophosphite). With increase in sodium hypophosphite Ni forms amorphous phase and as a result the micro hardness of the coating gets reduced. Heat treatment was carried out at 400 �C for 1 h after the coating, resulted in the formation of an intermetallic nickel phosphide (Ni3P) phase which improved the hardness of the Ni-P coating from 400 � 25 to 700 � 25 HV. A composite coating is formed due to the incorporation of nano alumina in the Ni-P coating leading to an increase in the hardness. The chemical composition of nickel gets reduced from 85.3 to 77.8 wt.% due to the presence of alumina which resists the deposition of Ni. The uniform distribution of alumina particles are observed using a scanning electron micrograph and confirmed by X-ray diffraction techniques. The specific wear rate of Ni-P-Al2O3 coated and post coating heat treated specimens was observed to be less when compared with that obtained in the case of conventional Ni-P coating. � 2014 Elsevier B.V. All rights reserved.

Low-energy ball milling of aluminum and nickel particles with an overall composition corresponding to the NiAl intermetallic phase was performed up to milling durations of 13 h. The milled powders and cold-compacted pellets were ignited using a low-energy spark. Interrupted thermal analysis and X-ray diffraction was performed to investigate the effect of milling time on intermetallic phase formation. The results show that microstructural refinement with increasing milling times increases reactivity, where the intermetallic formation temperatures reduce to those of sputtered multilayer foils with a similar phase formation sequence. NiAl intermetallic phase starts forming at 12 h of milling. Loose powders milled for 11 and 12 h and the corresponding pellets ignite locally with uniform thermal wave fronts self-propagating at velocities up to 0.24 m/s. © © 2013 Elsevier B.V. All rights reserved. 101 275 278 275-278

Sputtered aluminum doped zinc oxide (ZnO:Al) layers on borosilicate glass were exposed to damp heat (85 C/85% relative humidity) for 2876 h to accelerate the physical and chemical degradation behavior. The ZnO:Al samples were characterized by electrical, compositional and optical measurements before and after degradation. Hall measurements show that the carrier concentration stayed constant, while the Hall mobility decreased and the overall resistivity thus increased. This can be explained by the increase of potential barriers at the grain boundaries due to the occurrence of space charge regions caused by additional electron trapping sites. X-Ray Diffraction and optical measurements show that the crystal structure and transmission in the range 300-1100 nm do no change, hereby confirming that the bulk structure stays constant. Furthermore, on the surface, white spots appeared, containing elements that migrated from the glass, like silicon and calcium, which reacted with elements from the environment, including oxygen, carbon and chlorine. Depth profiling showed that the increase of the potential barrier is caused by the diffusion of H 2O/OH- through the grain boundaries leading to the formation of Zn(OH)2 or similar species or adsorption of species. They also indicate the presence of chloride and sulfide in the top layer and the possible presence of Zn5(OH)8Cl2·H 2O and Zn4SO4(OH)6·nH 2O

The potential of UV-light for the photochemical synthesis and stabilization of non-equilibrium crystalline phases in thin films is demonstrated for the β-Bi O polymorph. The pure β-Bi O phase is thermodynamically stable at high temperature (450-667 °C), which limits its applications in devices. Here, a tailored UV-absorbing bismuth(III)-N-methyldiethanolamine complex is selected as an ideal precursor for this phase, in order to induce under UV-light the formation of a -Bi-O-Bi- continuous network in the deposited layers and the further conversion into the β-Bi O polymorph at a temperature as low as 250 °C. The stabilization of the β-Bi O films is confirmed by their conductivity behavior and a thorough characterization of their crystal structure. This is also supported by their remarkable photocatalytic activity. Besides, this processing method has allowed us for the first time the preparation of β-Bi O films on flexible plastic substrates, which opens new opportunities for using these materials in potential applications not available until now (e.g., flexible photocatalytic reactors, self-cleaning surfaces or wearable antimicrobial fabrics). Therefore, photochemical solution deposition (PCSD) demonstrates to be not only an efficient approach for the low temperature processing of oxide films, but also an excellent alternative for the stabilization of metastable phases., This work was financed by Spanish Project MAT2013-40489-P and MAT2016-76851-R. The COST Action IC1208 also contributed to this study. I.B. acknowledges the financial support by Fundación General CSIC (Spanish ComFuturo Programme).

The crystal structures of two mononuclear Cu(II) NH2trz complexes [Cu(NH2trz)4(H2O)](AsF6)2 (I) and [Cu(NH2trz)4(H2O)](PF6)2 (II) as well as two coordination polymers [Cu(μ2-NH2trz)2Cl]Cl·H2O (III) and [Cu(μ2-NH2trz)2Cl] (SiF6)0.5·1.5H2O (IV) are presented. Cationic 1D chains with bridging bis-monodentate μ2-coordinated NH2trz and bridging μ2-coordinated chloride ligands are present in III and IV. In these coordination polymers, the Cu(II) ions are strongly antiferromagnetically coupled with J = -128.4 cm-1 for III and J = -143 cm-1 for IV (H = -JΣSiSi+1), due to the nature of the bridges between spin centers. Inter-chain interactions present in the crystal structures were taken into consideration, as well as g factors, which were determined experimentally, for the quantitative modeling of their magnetic properties. © 2013 by the authors; licensee MDPI, Basel, Switzerland.