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The magnetic phase diagram of bulk Cr100 x shows interesting behaviour close to the triple point concentration of x ≈ 2. Since the magnetic properties of Cr are influenced by dimensionality, stress and strain, this study focussed on the investigation of Cr99Al1 thin films prepared on fused silica substrates with thicknesses t varying from 29 to 452 nm using sputtering techniques. Resistance measurements covering the temperature range 2 to 400 K did not show any clear anomalies that could be indicative of changes in the magnetic ordering. X-ray diffraction (XRD) and atomic force microscopy (AFM) studies indicate the films are polycrystalline textured and that the 80 nm sample has the smallest grain size. In-plane stresses in these thin films were studied using the specialised XRD sin² ψ-method. The results show that the stress varies with film thickness. The 29 nm sample has stress in the order of 833 MPa and with increasing film thickness the stress reaches 1471 MPa for the 80 nm layer, where after it systematically reduces for the thicker coatings to 925 MPa for the 452 nm film. The highest stress for the Crx shows interesting behaviour close to the triple point concentration of x ≈ 2. Since the magnetic properties of Cr are influenced by dimensionality, stress and strain, this study focussed on the investigation of Cr99Al1 thin films prepared on fused silica substrates with thicknesses t varying from 29 to 452 nm using sputtering techniques. Resistance measurements covering the temperature range 2 to 400 K did not show any clear anomalies that could be indicative of changes in the magnetic ordering. X-ray diffraction (XRD) and atomic force microscopy (AFM) studies indicate the films are polycrystalline textured and that the 80 nm sample has the smallest grain size. In-plane stresses in these thin films were studied using the specialised XRD sin² ψ-method. The results show that the stress varies with film thickness. The 29 nm sample has stress in the order of 833 MPa and with increasing film thickness the stress reaches 1471 MPa for the 80 nm layer, where after it systematically reduces for the thicker coatings to 925 MPa for the 452 nm film. The highest stress for the Cr99Al1 thickness sample series is seen in the film with the smallest grain size. [ABSTRACT FROM AUTHOR]

Abstract: Alloys of the Pt–V system between 0 and 50 at.% V have been investigated by X-ray scattering and extended X-ray absorption fine structure (EXAFS). The variation of lattice parameter with the nominal chemical composition was measured and compared to previously reported values. The solid solution was observed in alloys containing up to 20 at.% V. In the alloy with higher vanadium concentration, 50 at.% V, we found that the alloy is not homogeneous and exhibits a segregation of Pt and PtV phases in addition to VO2(M) phase. These experiments are complemented by EXAFS measurements made at the K edge of V which clearly show the sensitivity of this technique to V content. Determination of the local environment of V and Pt is made via a basic model taking in account the first neighbours only. A discussion is presented about the comparison between X-ray and EXAFS results obtained from the same samples. [Copyright &y& Elsevier]

Africa is the only habitable continent that is not yet host to a light source - an important tool across disciplines. Scientists from the Executive Committee of the African Light Source Foundation discuss work towards building an advanced light source in Africa, and what remains to be done., Competing Interests: Competing interestsThe authors declare no competing interests., (© Springer Nature Limited 2022.)

The electrochemical performance of hydrothermal synthesized three dimensional (3D) orthorhombic vanadium pentoxide (V 2 O 5 ) nanosheets and vanadium pentoxide/graphene foam (V 2 O 5 /GF) composites at different mass loading of GF were successfully studied. The optimized V 2 O 5 /GF-150 mg composite provided a high specific capacity of 73 mA h g -1 , which was much higher than that the pristine V 2 O 5 (60 mA h g -1 ) nanosheets at a specific current of 1 A g -1 . A hybrid capacitor was also fabricated by adopting a carbon-based negative electrode obtained from the pyrolysis of an iron-PANI polymer (C-Fe/PANI) mixture and the 3D V 2 O 5 /GF-150 mg composite as the positive electrode in 6 M KOH electrolyte. The hybrid device of V 2 O 5 /GF-150 mg//C-Fe/PANI demonstrated a high energy density of 39 W h kg -1 with a corresponding high power density of 947 W kg -1 at a specific current of 1 A g -1 in an operating voltage window of 0.0-1.6 V. The hybrid device also exhibited an excellent cycling stability with 74% capacity retention recorded for up to 10,000 constant charging-discharge cycles and an excellent ageing test at a specific current of 10 A g -1 ., (Copyright © 2018 Elsevier Inc. All rights reserved.)