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The reversible and irreversible cationic and anionic charge compensation mechanisms occurring along the first charge and discharge cycle of Li- and Mn-rich Li[Li0.2Ni0.16Mn0.56Co0.08]O2 cathode material at (dis)charge rates of 0.1C and 5C have been identified and quantified by X-ray absorption and emission spectroscopy. The analysis provided the oxidation states of the transition metals, the Mn local coordination, and the lattice elastic constants. Lattice softening occurs along the first charge, while a minor spinel phase forms irreversibly at the expense of the layered phase. Higher charge rate increases the spinel formation and induces an increased softening in the delithiated lattice, which is expected to correspond to a reduced reversible anionic redox. The results evidence a comparable cationic and anionic oxidation since the beginning of the charge, while only anions are contributing towards its end, equivalent to roughly 10% of structural oxygen irreversibly lost. Higher charge rates resulted in a decreased reversible anionic redox, anticipating the cationic oxidation. The reported results provide a reliable experimental approach to characterize the key parameters controlling the reversible and irreversible cationic and anionic contributions to the charge compensation mechanism., This research was funded by the Spanish Government, through the “Severo Ochoa” Programme for Centers of Excellence in R&D (FUNFUTURE, CEX2019-000917-S), the projects RTI2018-097753-B-I00, MAT2017-91404-EXP, with FEDER co-funding, the CSIC program for the Spanish Recovery, Transformation and Resilience Plan “Plataforma Temática Interdisciplinar Transición Energética Sostenible+ (PTI-TRANSENER+)” funded by the Recovery and Resilience Facility of the European Union, established by the Regulation (EU) 2020/2094. A.K., H.C., M.K., D.B. and S.P. would like to acknowledge financial support from the German Federal Ministry of Education and Research (BMBF) within the ExcellBattUlm project (03XP0257D), the European Commission within the Si-DRIVE project (Horizon 2020, 814464), and the Helmholtz Association., With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000917-S).

La1−xBixFeO3 (x = 0.00, 0.05, 0.10, 0.15, 0.20) multiferroic perovskite has been characterized combining X-ray diffraction and synchrotron radiation X-ray absorption spectroscopy. Using the two techniques, we have evaluated how the average and local structures around Fe change upon introducing and increasing Bi doping into LaFeO3 structure. The structural characterization at long and short ranges has been correlated with the modulation of the magnetic properties of Bi-doped LaFeO3 as a function of the Bi/La ratio within the structure. XRD shows that the synthesis via auto-combustion citrated route produces single-phase Bi3+ ion-doped LaFeO3 perovskite, and Goldschmidt’s tolerance factor confirms the phase stability of the prepared system. Locally the EXAFS data analysis evidences an asymmetry reduction in the octahedron 〈FeO6〉, which is associated with an increase of oxygen vacancies due to Bi doping effect. The drop in the magnetization observed upon doping can be correlated to structural modification towards asymmetry reduction. Dilution of LaFeO3 with Bi ions enhances the functionality of this perovskite in various potential applications. This study can help to mark criteria for the tailoring of new smart materials with different intriguing properties. The XRD and XAFS support the smooth structural transition towards structural asymmetry reduction.

In this work, the structural and magnetic properties of multiferroic La 1 - x Y x FeO 3 perovskites, (x = 0.00, 0.05, 0.10, 0.15, 0.20, 0.25 and 0.30) synthesized through Sol-gel auto-combustion technique were investigated.The room temperature synchrotron X-ray diffraction (XRD) analysis revealed that the all the synthesized samples consisted of the polycrystalline orthorhombic structure perovskites (space group pnma), and tolerance factor confirmed the phase stability of the prepared perovskite system.The Williamson-Hall plots based on synchrotron XRD data were employed to estimate the average particle diameter and vary from 18.8 nm to 37.5 nm.For a deeper insight into the crystal structure, high-resolution transmission microscopy imaging (HRTEM) was performed.The estimated values of crystallite size from HRTEM and synchrotron XRD data were coincident.Many of crystallographic parameters and electron density measurements were calculated by Rietveld refinement of synchrotron XRD data. La 1 - x Y x FeO 3 perovskite crystals are canted antiferromagnets with a weak ferromagnetism at room temperature.Selected Area Electron Diffraction (SAED) patterns of the investigated samples exhibited spotty ring patterns, confirming the polycrystalline character.The magnetic properties were gotten through analyzing the magnetization versus temperature M(T) and M(H) hysteresis loop which characterized by a vibrating sample magnetometer (VSM). The orthoferrite La 1 - x Y x FeO 3 crystals are a promising candidate for optical device applications in broad temperature range and high power system.

The local structural and electronical transformations occurring along the first charge and discharge cycle of Li- and Mn-rich Li[Li0.2Ni0.16Mn0.56Co0.08]O2 cathode material have been characterized by X-ray absorption spectroscopy at several complementary edges. The irreversible spinel formation, occurring at the expenses of the cycling layered phase during the first charge, is quantified (about 10%) and spatially localized. The local strains induced by the Ni oxidation have been evaluated. They induce the formation of a low spin Mn3+ in the layered structure in parallel to the irreversible formation of the spinel phase in the particles bulk. The charge balance has been quantified for all the elements along the first charging cycle, confirming a reversible oxygen oxidation along the charge. Overall, these quantitative results provide an experimental basis for modeling aimed to control the structure and its evolution, for instance, hindering the spinel formation for the benefit of the material cycle life., This research was supported by the Spanish Government, through the “Severo Ochoa” Programme for Centers of Excellence in R&D (FUNFUTURE CEX2019-000917-S), and the projects MAT2017-91404-EXP, RTI2018-096273-B-I00, and RTI2018-097753-B-I00 with FEDER cofunding. D.T. participates in the FLOWBAT 2021 platforms promoted by the Spanish National Research Council (CSIC). The HIU authors acknowledge the basic funding from the Helmholtz Association.

The World Health Organization (WHO) announced that the novel coronavirus pneumonia pandemic caused by SARS-CoV-2 was classified as a public health emergency of international concern on January 30, 2020 Egypt's health ministry had announced the first case in the country at Cairo International Airport involving a Chinese national on 14 February 2020. Case decisions in the cath labs should be individualized, taking into account the risk of 2019 novel coronavirus (COVID-19) exposure versus the risk of delay in diagnosis or therapy. In patients with known or suspected COVID-19 and ischemic heart disease, the balance of staff exposure and patient benefit will need to be weighed carefully. Aim of the work: Analyzing and assessing the impact of COVID 19 pandemic on the: (1) volume, type of patients, and the different procedures performed. (2) The changes in management trends of cardiologists in the cath labs. Results: This study has surveyed 30 cath labs distributed all over Egypt during COVID-19 pandemic with 43.35% in urban area and 56.7% in rural areas. Only 63.3% of surveyed centers were well equipped to deal with COVID-19 active patients and full personal protective equipment was worn in only 6.7% of patients. A decrease in the volume of new acute coronary syndrome (ACS) patients, ST-elevation myocardial infarction patients and primary percutaneous coronary intervention (PCI) was recorded in 80%, 83%, and 80% of the surveyed centers respectively. Regarding the delay in the invasive management for patients with ACS due to diagnostic testing, there was 100% delay in all surveyed centers with 70% of centers suffering from delay in primary PCI due to awaited testing. On the other hand, there was a decrease in the volume of patients receiving elective procedures in 83.3% of cath labs. Conclusion: The management trends in the current Egyptian survey were significantly impacted during COVID-19 pandemic. Primary PCI volume much reduced and takes longer time than should be.

Single-phase lanthanum orthoferrite (LaFeO3) was prepared by an auto-combustion method. The analysis of synchrotron room temperature X-ray diffraction (XRD) data confirmed the orthorhombic LaFeO3 perovskite of space group Pnma without any impurity phase. The Scherrer's formula and Williamson-Hall plot based on XRD data were employed to estimate the crystallite size of the prepared sample. For a deeper insight into the crystal structure, high-resolution transmission microscopy imaging (HRTEM) was performed. The estimated values of crystallite size from HRTEM and synchrotron XRD data were coincident. The HRTEM images confirmed the polycrystalline nature of the prepared sample through the obvious lattice planes which are related to (121) plane. Furthermore, the M(H) hysteresis loop of the investigated sample was characterized by a vibrating sample magnetometer (VSM). The magnetic properties obtained through analyzing the magnetization versus temperature M(T) and magnetization versus magnetic field M(H) curves indicated that LaFeO3 possessed weak ferromagnetism at room temperature.

Superparamagnetic iron oxide nanoparticles (SPION) Fe3O4 nanoparticles were prepared using different approaches: co-precipitation and sonochemical methods. This article is a comparative study on how different synthesis techniques greatly affect the magnetic properties and heating efficiency of such nanomaterial. Another important issue addressed here is the correlation between microstructure, colloidal stability, magnetization and specific absorption rate (SAR) of the nanoparticles. The results reveal that the sonochemical method for polyethylene glycol (PEGylated) Fe3O4 with size 5 nm leads to pseudo single domain with smallest loop area. Additionally, large SAR values are obtained within 10–15 min using low magnetic field.