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Scanning electron microscopy with energy dispersive X-ray microanalysis, transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy were employed to study the effect of mechanical treatment on the structure, morphology, surface chemical state, and composition of Ti6Al4V alloy. The ultrasonic impact treatment of Ti6Al4V in air with a duration ranging from 30 to 150 s was revealed to result in the build-up of an amorphous mixed oxide layer the thickness of which increased with treatment time, attaining a maximum value of about 12.3 μm. The mechanochemical oxidation of the alloy was accompanied by incorporation of nitrogen from the atmosphere and concurrent strong segregation of carbon atoms from the bulk to form dispersed nitride/oxynitride, carbide/oxycarbide, and oxycarbonitride phases. The nitrogen atoms, penetrating deep into the alloy, seemed to produce a nitrogen-enriched α-Ti(N) phase. Alongside with this, the material transfer from the hardened steel pin to the alloy was detected. At the oxide-metal interface, the oxidation induced segregation of Al, V and Fe was observed. The impact treatment of the alloy in air gave rise to an increase in the microhardness and improvement of tribological properties. A possible mechanism of mechanochemical oxidation of the alloy is suggested. [ABSTRACT FROM AUTHOR]

Abstract: A Ni–ScSZ cermet is widely used as the anode in a solid oxide fuel cell because it possesses the appropriate electrochemical properties. However, it is susceptible to degradation during operation. Samples of a NiO–ScSZ composite were reduced in pure and diluted hydrogen to determine the microstructural evolution and the degradation behavior of the material. The resulting changes in microstructure were investigated using scanning transmission electron microscopy, X-ray energy dispersive spectroscopy and electron energy loss spectroscopy. The resulting data revealed that the various conditions during the reduction processes had a significant effect on the microstructures. The high porosity of the reduced nickel phase and cracking between the Ni and the ZrO2 phases after reduction resulted in a reduction in the strength of the anode material. [Copyright &y& Elsevier]

Abstract: To treat tumours efficiently and spare normal tissues, targeted drug delivery is a promising alternative to conventional, systemic administered chemotherapy. Drug-carrying magnetic nanoparticles can be concentrated in tumours by external magnetic fields, preventing the nanomaterial from being cleared by metabolic burden before reaching the tumour. Therefore in Magnetic Drug Targeting (MDT) the favoured mode of application is believed to be intra-arterial. Here, we show that a simple yet versatile magnetic carrier-system (hydrodynamic particles diameter <200nm) accumulates the chemotherapeutic drug mitoxantrone efficiently in tumours. With MDT we observed the following drug accumulations relative to the recovery from all investigated tissues: tumour region: 57.2%, liver: 14.4%, kidneys: 15.2%. Systemic intra-venous application revealed different results: tumour region: 0.7%, liver: 14.4 % and kidneys: 77.8%. The therapeutic outcome was demonstrated by complete tumour remissions and a survival probability of 26.7% (P =0.0075). These results are confirming former pilot experiments and implying a milestone towards clinical studies. From the Clinical Editor: This team of investigators studied drug carrying nanoparticles for magnetic drug targeting (MDT), demonstrating the importance of intra-arterial administration resulting in improved clinical outcomes in the studied animal model compared with intra-venous. [Copyright &y& Elsevier]

Abstract: X-ray photoelectron spectroscopy and scanning electron microscopy with energy dispersive X-ray microanalysis were employed to study the effect of mechanical treatment on the surface chemical state, composition and morphology of commercial Tiyph name="sbnd" />4V alloy. It has been demonstrated that ultrasonic impact treatment of Tiyph name="sbnd" />4V in a liquid nitrogen (LN2) environment results in substantial grain refinement and formation of nitrides and oxynitrides of all the alloy components. The mechanochemical synthesis of the nitrides and oxynitrides from LN2 was found to efficiently occur not only within the impacted area but outside it as well. The layer with a high content of incorporated nitrogen and average atomic ratio N/Ti=0.94 was estimated to be at least ∼2μm thick. As a result of the combined effect of cryogenic deformation, nanoscale grain refinement and nitriding, a 3-fold increase in the microhardness of Tiyph name="sbnd" />4V alloy is obtained. The impact treatment in LN2 was observed to be accompanied by material transfer from the hardened steel pin to the alloy followed by incorporation of the pin components into Tiyph name="sbnd" />4V and formation of the Feglyph name="sbnd" />C and Ti/ce:simple-para> [Copyright &y& Elsevier]

Abstract: Electron Energy Loss Spectroscopy has been employed for investigation of the surface and bulk plasmon excitations versus heating in the Co–Cr–Mo alloy surface for the primary electron beam energies Е 0 ranging from 150 to 800 eV. For the annealed alloy the experimental values of the plasmon energy are localized at more energies as compared to the non–annealed alloy. It was established that heating of the alloy promotes to insignificant deviations of the plasmon excitations. Damping of the intensity line of surface plasmon with a increase of heating was established. Physical processes which can influence on the energy displacements of long wavelength plasmon oscillations and damping of surface plasmon in the characteristic loss spectra at heating are considered. [Copyright &y& Elsevier]

Abstract: Electron Energy Loss Spectroscopy has been employed for investigation of the electronic states of amorphous and crystalline Fe73.6Cu1Nb2.4Si15.8B7.2 (FINEMET) alloy surface and alloy components. Electron energy losses have been measured for primary electron beam energies E 0 from 150 to 650 eV. The characteristic energy loss spectra were composed of main peaks which we have interpreted due to surface and bulk plasmons, a combination of surface and bulk losses, high harmonics of plasma losses, inter-band transitions and ionization of core levels. The measured energies for the plasmon excitations were found not to agree with calculated values according to the classical theory for the collective oscillations in solids. Changes in the intensity lines of the surface and bulk plasmons were observed for all specimens depending on primary electron energy E 0. The present results are compared with characteristic energy loss data reported in the literature. [ABSTRACT FROM AUTHOR]

Abstract: Ionization Spectroscopy has been used to study thermo-induced surface segregation in the near-surface region of the ternary Co–Cr–Mo alloy. For the non-annealed alloy the Mo atoms preferred segregation in the outermost layers and Cr atoms segregation in the underlying layers of surface was observed at room temperature. Heating of the alloy promotes increasing of Co concentration and decreasing of Mo concentration in the near-surface region. For the annealed alloy the insignificant Mo atoms segregation on the outermost layers and enrichment with Co and Cr atoms in underlayers are displayed. The present results are compared with several theories of segregation. [Copyright &y& Elsevier]

Abstract: Electron energy-loss spectroscopy has been employed for investigation of the electronic structure of the metals Pd, Cu and the ordered Cu75Pd25(100) alloy surfaces. Electron energy losses have been collected using primary electron beam energies ranging from 150 to 800eV. All of the energy losses observed in these samples can be explained in terms of three types of loss mechanisms, namely, electronic transitions involving excited states, excitation of plasma oscillations and ionization of core levels. An essential deviation of the plasmon losses from the theoretical value as calculated on the basis of the free-electron gas model was found for Pd, Cu and the Cu75Pd25(100) alloy. Using analysis of the intensity of surface and bulk plasmons we can define the interval of primary electron energy Е 0, where the electron beam scans only the near surface region. Experimental data are compared with optical data obtained by LMTO–ASA calculations. [Copyright &y& Elsevier]

Abstract: Electron energy loss spectroscopy has been employed for investigation of the effect of 600eV Ar+-ion irradiation in the dose range 7×1016–4×1017ions/cm2 on the atomic structure and surface composition of alloy Pt80Co20(111). A method of the layer-by-layer reconstruction of the lattice interplanar distance changes based on the analysis of the plasmon spectra excitation was proposed. The ion bombardment was shown to result in a non-monotonic variation of the lattice interplanar distance due to formation of the stable defects, with the topmost layer being in the state of compression. Using the ionization energy loss spectra, a layer-by-layer concentration profile of the alloy components was reconstructed for different doses of ion irradiation of the surface. The Ar+-ion bombardment of the alloy was found to result in the preferential sputtering of Co and in the enrichment of the near-surface region by Pt atoms with formation of an altered layer, which is characterized by a non-monotonic concentration profile dependent on the irradiation dose. The results obtained are discussed in the framework of the models of preferential sputtering and radiation-induced segregation. [Copyright &y& Elsevier]

The low-energy electron diffraction method with a number of original techniques has been employed to observe and study a new radiation-stimulated reconstruction transition on the CoNi3 (1 0 0) single crystal surface. Low-energy bombardment by Ar+ ions (600 eV) leads to a change of the diffraction pattern symmetry corresponding to a surface structure change f.c.c.→h.c.p. To elucidate the causes of the effect observed the changes of the surface composition and the concentration profile under the action of ion bombardment were studied. It has been found that first atomic layer of the sample is fully enriched in cobalt, and this, precisely, leads to the formation of the h.c.p. phase on the surface. [Copyright &y& Elsevier]

This paper presents a first part of research of designing a new Ti–Si–C-based composite for potential application as a solid oxide fuel cells interconnect material. Spark plasma sintering technique was used for the production and the effects of sintering parameters on microstructure, phase composition, as well as mechanical and electrical properties were investigated. Optimization of the sintering conditions then allowed to obtain a fine-grained material with properties (bending strength 433 MPa, hardness of 9.6 GPa, electrical resistance 26 mΩ cm) surpassing those of Crofer steels, materials typically used in the SOFC interconnect applications nowadays. This is a very promising result, yielding our Ti–Si–C composite a serious candidate for new-generation lightweight interconnect materials. [ABSTRACT FROM AUTHOR]

The SARS-CoV-2 pandemic has hit the European region disproportionately. Many HIV clinics share staff and logistics with infectious disease facilities, which are now on the frontline in tackling COVID-19. Therefore, this study investigated the impact of the current pandemic situation on HIV care and continuity of antiretroviral treatment (ART) supplies in CEE countries. The Euroguidelines in Central and Eastern Europe (ECEE) Network Group was established in February 2016 to review standards of care for HIV in the region. The group consists of professionals actively involved in HIV care. On March 19, 2020 we decided to review the status of HIV care sustainability in the face of the emerging SARS-CoV-2 pandemic in Europe. For this purpose, we constructed an online survey consisting of 23 questions. Respondents were recruited from ECEE members in 22 countries, based on their involvement in HIV care, and contacted via email. In total, 19 countries responded: Albania, Armenia, Belarus, Bosnia and Herzegovina, Bulgaria, Croatia, Czech Republic, Estonia, Georgia, Greece, Hungary, Lithuania, Macedonia, Poland, Republic of Moldova, Russia, Serbia, Turkey, and Ukraine. Most of the respondents were infectious disease physicians directly involved in HIV care (17/19). No country reported HIV clinic closures. HIV clinics were operating normally in only six countries (31.6%). In 11 countries (57.9%) physicians were sharing HIV and COVID-19 care duties. None of the countries expected shortage of ART in the following 2 weeks; however, five physicians expressed uncertainty about the following 2 months. At the time of providing responses, ten countries (52.6%) had HIV-positive persons under quarantine. A shortage of resources is evident, with an impact on HIV care inevitable. We need to prepare to operate with minimal medical resources, with the aim of securing constant supplies of ART. Non-governmental organizations should re-evaluate their earlier objectives and support efforts to ensure continuity of ART delivery. [ABSTRACT FROM AUTHOR]

Abstract: The development of the interdiffusion processes and the surface morphology changes in thin films of Au(120 nm)/Ni(70 nm) during annealing at 200 °C for 20 min in vacuum with different residual atmosphere pressures of 10−3 and 10−6 Pa and in an environment of hydrogen at a pressure of 5 × 102 Pa have been studied. Secondary ion mass spectrometry, Auger electron spectroscopy, X-ray diffraction, optical microscopy, atomic force microscopy and scanning electron microscopy were used. Surface microdefects that form in the films are related to the local oxidation of nickel and to the stress that arises due to interdiffusion. Defect formation and reactions at the surface are found to be controlling factors in the transport of nickel to the surface and in the observed morphology. [Copyright &y& Elsevier]

Abstract: The thermo-mechanical analytical model proposed for different solid oxide fuel cell (SOFC) designs addresses the deformation behavior and mechanical stability of SOFCs at various thermal stresses, specifically the creep resistance and the long-term endurance beyond the elastic limit. The model considers the deformation of multi-layer SOFC in the temperature range of 600–800 °C and presents the combination of the correlated parameters for SOFC performance evaluation, stability and long-term endurance under realistic operating conditions and temperature gradients. The numerical analysis of the thermo-mechanical properties of the SOFC materials is presented in terms of mechanical behavior at failure conditions and the influence of rheological and structural properties on SOFC long-term endurance. The SOFC thermal behavior, creep parameters of the SOFC materials and long-term stability are analyzed in terms of stresses, deformations and displacements. In terms of broader impact, the algorithms for Maurice-Levi and Voltaire theorems and their validity for non-elastic, e.g. viscous-elastic, viscous-plastic, and elastic-plastic deformations were confirmed. This result allowed us to apply the stress condition of non-elastic body to the stress condition of the elastic body which is relevant to the SOFC operation at elevated temperatures. [Copyright &y& Elsevier]