Conveners
POSTER: Session - 11
- Karel Saksl (TUKE)
- Pavol Sovák (Pavol Jozef Šafárik University in Košice, Faculty of Science, Institute of Physics)
Soft magnetic composites (SMCs) are a promising class of materials for high-frequency magnetic components in power electronics applications, including electric vehicle on-board chargers, DC-DC converters, and grid-tied inverters. Accomplishing higher operating frequencies than laminated steels and higher saturation flux density than common ferrites, SMCs consist of electrically insulated...
Hard carbon is a promising alternative anode material for lithium-ion batteries due to its low cost, structural stability, and ability to store Li$^+$ ions. However, its electrochemical performance is strongly affected by carbonisation temperature, precursor type, surface chemistry, and the presence of heteroatom dopants. This work compares literature-reported hard carbon materials prepared...
Hot Jupiters are a unique group of planets that cannot be found in our Solar system. They are placed closer than 0.1 AU from their parent stars, which often results in transits that can be detected by photometric observations. Interiors of hot stars are able to conserve their angular momentum for longer time, keeping rotational velocities high for whole lifetime. If there is a planet orbiting...
Monodisperse CoFe₂O₄ nanoparticles with an average core size of approximately 9 nm were synthesized by thermal decomposition and surface-engineered for magnetic particle hyperthermia. Polyacrylic acid (PAA) coating was employed to improve aqueous dispersibility and provide reactive groups for subsequent covalent attachment of lysine, tryptophan, and elastin via EDC/NHS coupling. The resulting...
Magnetic resonance imaging (MRI) is a non-invasive diagnostic technique that provides high-resolution images of internal tissues based on nuclear magnetic resonance. It relies on the interaction between hydrogen nuclei and an external magnetic field to generate contrast between different biological structures. Contrast agents are often used in MRI to enhance image quality and improve...
High-energy synchrotron X-ray diffraction and $^{57}$Fe Mössbauer spectroscopy were combined to resolve the phase evolution and local magnetic environments in mechanically alloyed Fe$_{73.5-x}$Mn$_{x}$Cu$_{1}$Nb$_{3}$Si$_{13.5}$B$_{9}$ with ($x$ = 2, 4, 6, 8, 10 at.%) powders. Elemental mixtures were dry-milled for 30 h in a RETSCH PM400 planetary ball mill at 250 rpm using a ball-to-powder...
Demultiplexers are the fundamental primitives of network architecture, enabling perfect routing of an input classical signal to a designated one, among multiple output ports. Quantum transmission lines, having access to the quantum systems directly, are able to transmit both the classical and quantum information encoded in quantum systems. A natural question therefore emerges that whether the...
Medium-entropy alloys (MEAs) are multi-principal element systems in near-equimolar ratios (5 – 35 at. %) that provide a versatile platform for the development of solid-state hydrogen storage materials. In particular, alloys with a body-centered cubic (BCC) structure are attractive due to their high density of interstitial sites available for hydrogen accommodation. This study investigates a...
High-entropy alloys based on Ti, V, Nb, Cr and Mn have attracted interest as potential hydrogen storage materials due to the possibility of tailoring their structural and hydrogen sorption properties through compositional and processing modifications. In this study, the phase composition, microstructure and hydrogen absorption behaviour of TiVNbCrMn and TiVNbCrMnFe alloys prepared by arc...
High-entropy oxides (HEOs) are materials in which five or more cations share a common crystallographic lattice that is stabilized by high configurational disorder [1]. The presence of multiple principal elements allows their deliberate selection, thus tuning or fundamentally altering the properties of the compound. Despite often crystallizing in simple average structures, HEOs exhibit...
Within the MASS-PRAM project, a new Anton Paar XRDynamic 500 X-ray diffractometer was acquired at the Institute of Physics, Pavol Jozef Šafárik University in Košice for the structural characterization of various materials. The instrument operates with Cu-K$\alpha$ radiation and allows goniometer configurations with radii of 360 mm and 400 mm.
The performance of the diffractometer was...
Low-dimensional spin-1/2 Heisenberg antiferromagnets provide an ideal platform for studying topological magnetic phases, including a magnetic Berezinskii–Kosterlitz–Thouless (BKT) transition. The previously well-studied metal-organic complex Cu(pm)(ea)$_2$ (pm = pyromellitic acid anion, [C$_6$H$_2$(COO)$_4$]$^{4-}$; ea = ethylamine cation, [C$_2$H$_5$NH$_3$]$^+$) represents a...
Human cytomegalovirus (HCMV) employs multiple viral glycoproteins to regulate cell entry, intracellular trafficking and immune evasion. The immunomodulatory glycoprotein UL141 interacts with the viral envelope glycoprotein gH and the cellular death receptor TRAIL-R2. However, the structural basis of these interactions and their potential modulation by synthetic ligands remain poorly...
NanoLuc, a superior β-barrel fold luciferase, was engineered 10 years ago but the nature of its catalysis remains puzzling. Here experimental and computational techniques are combined, revealing that imidazopyrazinone luciferins bind to an intra-barrel catalytic site but also to an allosteric site shaped on the enzyme surface. Structurally, binding to the allosteric site prevents simultaneous...
This study is devoted to the investigation of low-temperature thermal properties of phosphate glasses $DyₓY₁₋ₓ(PO₃)₃$ containing different concentrations of rare-earth $Dy³⁺$ ions. The gradual substitution of $Y³⁺$ by $Dy³⁺$ is expected to modify the local structure of the glass network and influence its thermal properties. A series of $DyₓY₁₋ₓ(PO₃)₃$ samples with $Dy³⁺$ content (x = 0,...
Oxide dispersion strengthened (ODS) alloys are composed of a metallic matrix (typically bcc or fcc) containing a uniform distribution of nanoscale oxide particles. These alloys generally exhibit strong mechanical performance, retaining high strength even at elevated temperatures reaching 800°C. In addition, the nanoscale precipitates function as trapping sites for defects generated by...
Type II spicules often fade rapidly from cool chromospheric lines, commonly interpreted as their heating to transition-region temperatures. Here, we test whether apparent fading can also arise from a primarily kinematic visibility effect. Using high-resolution 2.5D ideal-MHD simulations, we show that transverse oscillations of a super-Alfvénic magnetized jet trigger the Kelvin–Helmholtz...
Topological material $ZrTe_{5}$ exhibits a pronounced resistivity anomaly and a sequence of temperature-dependent electronic reconstructions whose microscopic origin remains under active debate [1,2].
Here, we present a symmetry-resolved Raman scattering study of $ZrTe_{5}$ single crystals in the ac plane over the temperature range 40-300 K. All symmetry-allowed Raman active phonons...
The sustainable transformation of industrial sectors and metallurgy is closely linked to the implementation of hydrogen technologies. However, the efficient operation of hydrogen technological systems (such as electrolyzers and fuel cells) relies on secondary energy storage systems capable of balancing dynamic power surges. Lithium-ion batteries (LIBs) integrated into these hybrid hydrogen...
Cometary dust provides a unique record of the primitive material from which the Solar System formed. Observations of the brightness, color, and polarization of cometary comae can be used to constrain the physical and compositional properties of their dust particles. Comet C/2012 S1 (ISON) was classified as a dynamically new comet arriving from the Oort Cloud on a near-parabolic orbit and was...
The subspace-search variational quantum eigensolver (SSVQE) algorithm is used on various atomic clusters of Be, B and C atoms to find their ground state and 1st excited state energy values. Various approximations such as active space and freeze core have been used to reduce the quantum qubit in the computation. The approximations affect the energy values for quantum mechanically big clusters...
When inhaled general anaesthetics are administered, pulmonary surfactant represents the first biological barrier they interact with. We investigated effects of primary aliphatic n-alcohols (CnOH, n = 8 – 18, 0.4 mol/mol), as simple models of inhaled general anaesthetics, incorporated into synthetic pulmonary surfactant models. Two lipid mixtures were used as model systems: S-model, consisting...
Understanding structure–property relationships in advanced materials requires complementary experimental techniques capable of probing structural organization across different length scales. The newly established MASS-PRAM laboratory at Pavol Jozef Šafárik University in Košice is being developed as a multimodal X-ray characterization platform integrating X-ray diffraction, X-ray scattering,...
HKUST-1 is a Cu(II)-based metal–organic framework constructed from copper paddlewheel units interconnected by benzene-1,3,5-tricarboxylate linkers [1]. Its high porosity and accessible coordinatively unsaturated Cu(II) sites support applications in adsorption, heterogeneous catalysis, environmental remediation, and biological or biomedical systems. However, its pronounced affinity toward water...
Urea-based cationic gemini surfactants with polymethylene spacers containing 2 to 10 methylene units were investigated with respect to their micellization behavior and their role as pore-forming agents in the synthesis of mesoporous silica nanoparticles. Micellar structures were characterized using small-angle neutron scattering (SANS) with various form-factor of core–shell and homogeneous...
Iron-based alloy systems Fe–(Al, Ga)–(P, C, B) rank among the softest magnetic materials obtained through controlled annealing (Hc ≈ 1.3 A/m annealed at 713 K ≈ 0.97Tg) to relieve internal stresses, i.e., after optimum relaxation of the amorphous structure. Low coercivity stems from the suppression of the formation of crystal nuclei of the iron and iron-metalloid compounds. High phosphorus (P)...
Cobalt ferrite (CoFe₂O₄) nanoparticles belong to the family of spinel ferrites whose structural properties are strongly influenced by particle size, morphology, and synthesis conditions. A detailed understanding of their crystal structure is therefore important for establishing relationships between synthesis, morphology, and the resulting material properties.
In this work, CoFe₂O₄...
Manganese telluride (MnTe) is a prototypical antiferromagnet with a spin-polarised electronic structure, recently classified as an altermagnet, with a critical temperature T_C≈310 K. In this work, we investigate the structural changes associated with magnetic moment reorientation in the altermagnetic phase using high-resolution X-ray diffraction (HR-XRD). Temperature-dependent diffraction...
GdMnO3 came to the attention of the scientists due to the discovery of multiferroicity in this compound. It crystallizes in the orthorhombically distorted perovskite structure; space group 𝑃𝑛𝑚𝑎; Gd ions are located on 4𝑐; Mn ions on 4𝑏 and oxygen anions are located on 4𝑐 and 8𝑑 crystallographic sites. The compound orders into antiferromagnetic phase below 𝑇N ~ 40 K [1] and then undergoes...
A key yet unresolved question of the pathogenesis of Alzheimer’s disease (AD) and other tauopathies is the mechanism of the transition from the unstructured monomeric tau protein to the insoluble filaments. In the physiological state, tau protein exists as a conformational ensemble of interconverting structures and on the scale of transition from monomeric through oligomeric and filamentous...
Previous studies [1] of $Cu(tn)Cl₂$ $(tn=C_3 H_{10} N_2)$ proved that the system is an excellent realization of a spin-1/2 two-dimensional (2D) quantum magnet. While previous work was unable to specify the type of 2D magnetic lattice, re-analysis of the thermodynamics data within the current theories suggests realization of a spatially anisotropic square lattice (SASL) with $R=J_1/J_2≈0.5$ and...
The present work reports a series of experiments aimed at the fabrication and investigation of photosensitive thin films operating in the 3-5 μm spectral range based on mercury chalcogenide colloidal quantum dots (CQDs), namely mercury telluride (HgTe) and mercury selenide (HgSe). Particular attention was devoted to the effect of ligand exchange on the structural and electrophysical properties...
The determination of stellar and orbital parameters in massive binaries is often complicated by phase-dependent variability in the line profiles. Classical spectral disentangling represents time-series spectra as contributions from Doppler-shifted, phase-invariant components [1, 2]. However, this approximation can be inadequate in systems affected by tidal deformation, gravity darkening,...
Co-based amorphous alloys combine high strength, favorable magnetic properties and chemical stability. Co–Fe–Ta–B alloys show excellent glass-forming ability and a supercooled liquid region near 70 K [1], with compressive yield strength exceeding 5000 MPa [2]. Their potential is also enhanced by high magnetic permeability, nearly zero magnetostriction and coercivity as low as 0.25 A/m [3]....
Thrombotic disorders remain a major cause of morbidity and mortality worldwide, while conventional antithrombotic therapy is limited by systemic drug exposure and associated bleeding risks. Magnetic drug delivery systems offer a strategy for increasing the local concentration of therapeutic agents at a thrombotic site through external magnetic guidance. In this work, Fe3O4@SiO2-based...
Radiotherapy delivered at ultra-high dose-rates (UHDR,> 40 Gy/s) can preserve tumour-control efficacy while reducing normal-tissue toxicity, a phenomenon known as the FLASH effect. Despite intense research efforts, the underlying mechanisms remain poorly understood and the conditions required for the occurrence of the FLASH effect are still under debate. Recent studies suggest that not only...
Recent interest in ultra-high-dose-rate (UHDR) irradiation and FLASH radiotherapy has stimulated the development of experimental platforms capable of delivering radiation under increasingly extreme temporal conditions. Short-wavelength photon sources are particularly attractive because they combine highly localized energy deposition with pulse structures spanning from nanoseconds to...
Fast, reversible, and low-power manipulation of the spin texture is crucial for next generation spintronic devices like non-volatile bipolar memories, switchable spin current injectors or spin field effect transistors. Ferroelectric Rashba semiconductors (FERSC) are the ideal class of materials for the realization of such devices. Their ferroelectric character enables an electronic control of...
Tungsten(VI) oxide (WO$_{3}$) is widely studied for photochromic and solar-energy-related applications, where its functional properties are strongly connected with changes in electronic structure and local atomic arrangement [1]. In nanocrystalline WO$_{3}$, the local structure can be sensitive not only to chemical modification, such as protonation, but also to synchrotron X-ray exposure...
