3D x-ray diffraction method at ESRF Grenoble (ID11 beamline) was applied to investigate grain resolved internal stress and strain around the martensite band front propagating in 0.1mm thin superelastic NiTi wire deformed in tension, We reconstructed internal stress and strain fields around the front and performed simulation by finite element implements SMA model. In this way we managed to solve the mesoscopic mechanism of localized deformation in NiTi....
How electronic charge is distributed over a molecule determines to a large extent its chemical properties. Here, we demonstrate how the electrostatic force field, originating from the inhomogeneous charge distribution in a molecule, can be measured with submolecular resolution. We exploit the fact that distortions typically observed in high-resolution atomic force microscopy images are for a significant part caused by the electrostatic force acting between charges of the...
Ferromagnets and antiferromagnets are the two basic forms of magnetically ordered materials. Traditionally we thought that magnetism can be easily controlled and utilized only in ferromagnets. Researchers from the Czech Republic, United Kingdom, and Germany change this perception by demonstrating electrical switching of magnetization in an antiferromagnetic microchip.
Ultra-high energy cosmic-ray air showers probe particle physics at energies beyond the reach of accelerators. We introduce a new method to test hadronic interaction models without relying on the absolute energy calibration, and apply it to events with primary energy 6-16 EeV, whose longitudinal development and lateral distribution were simultaneously measured by the Pierre Auger Observatory. The average hadronic shower is 1.33 ± 0.16 (1.61 ± 0.21) times larger than...
We prepared a two-dimensional (2D) analogue of a C70 fullerene peapod by the sequential assembly of 12C and 13C graphene single-layers, and C70 fullerenes. The local changes in the strain and doping were correlated with local roughness revealing asymmetry in the strain and doping with respect to the top and bottom layers. It is a first example of a carbon-only 2D nanoelectromechanical system. The concept is now exploited in design of 2D quantum computers using magnetic...
The experimental and theoretical study was dealing with dielectric properties of water molecules trapped in beryl crystals. Its crystal lattice provides nanoscopic regularly arranged sites where the trapped molecules can rotate. Unlike in liquid water, no hydrogen bonds are formed, but the molecules are interacting by their dipole moments. It has been proved that the molecules consequently tend to point in the same direction which implies producing a local electric field...
Spin-orbit coupling is a fundamental interaction in condensed systems, which plays an important role in modern application of magnetism such as current control of magnetic moments. We showed that in specific interacting electron systems spin-orbit interaction may arise by the mechanism spontaneous symmetry breaking. The new low-temperature state has peculiar magnetic properties, e.g., it carries a macroscopic spin current. We predict that in this state it is possible to...
We prepared and tested cobalt zinc ferrite encapsulated by amorphous silica in order to find a safe contrast agent and magnetic label MRI. Rat mesenchymal stem cells were labeled with a low, medium or high dose of CZF-NPs (0.05; 0.11 or 0.55 mM); silica NPs served as a positive control. Annexin V/Propidium Iodide labeling revealed no significant cytotoxicity for any group of treated cells and only a high dose of CZF-NPs slowed down cell proliferation and induced DNA...
We synthetized the Eu-doped Y3Al5O12 (YAG) powder phosphors by solid state reaction under reducing atmosphere. We studied their structural, optical and paramagnetic properties by means of X-ray diffraction, time-resolved luminescence spectroscopy and electron paramagnetic resonance. Correlated measurements showed that the single Eu2+ ions are stabilized in YAG structure at yttrium position and give rise to 440 nm emission. Such...
Direct interactions of plasma matter with living cells and tissues can dramatically affect their functionality. We studied the molecular mechanisms of non-thermal plasma-induced bacteria inactivation in both Gram-positive and Gram-negative strains. We demonstrate that depending on the exposure time plasma induces either direct physical destruction of bacteria or triggers programmed cell death that exhibits characteristic features of apoptosis. Our study opens new...
Akademie věd České republiky, 28.11.2018.
Unikátní laserové...
MÚ AV ČR, 26.11.2018.
Záznam přednášky dr. Martina Schnabla z...
Technologické centrum AV ČR, 11.10.2018.
Czech Liaison Office...
Radio Praha in English, 4.5.2018.
Experts from the Institute of...
