A5087845014- Physics of Superconductivity and Magnetism
- Superconductivity in MgB2 and Alloys
- Superconducting Materials and Applications
- Iron-based superconductors research
- Carbohydrate Chemistry and Synthesis
- Magnesium Alloys: Properties and Applications
- Glycosylation and Glycoproteins Research
- Magnetic properties of thin films
- Magnetic Properties and Applications
- Magnetic and transport properties of perovskites and related materials
- Thermal Expansion and Ionic Conductivity
- Microbial Metabolites in Food Biotechnology
- Particle accelerators and beam dynamics
- Synthesis of Organic Compounds
- Electronic Packaging and Soldering Technologies
- Boron and Carbon Nanomaterials Research
- Magnetic Properties of Alloys
- Enzyme Production and Characterization
- Analytical Chemistry and Chromatography
- Biofuel production and bioconversion
- HVDC Systems and Fault Protection
- Copper Interconnects and Reliability
- Quantum and electron transport phenomena
- Diet, Metabolism, and Disease
- Polysaccharides and Plant Cell Walls
Institute of Electrical Engineering of the Slovak Academy of Sciences
2015-2024
Slovak Academy of Sciences
2015-2024
Institute of Chemistry of the Slovak Academy of Sciences
1993-2022
National Institutes of Health
1996-2017
Institute of Electrical Engineering
2014-2015
Leibniz Institute for Solid State and Materials Research
2012
Slovak University of Technology in Bratislava
1994-2006
University of Lisbon
2005
Universidade Nova de Lisboa
2005
National Institute of Diabetes and Digestive and Kidney Diseases
1997-2002
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTA Fundamentally New, Simple, Stereospecific Synthesis of Oligosaccharides Containing the β-Mannopyranosyl and β-Rhamnopyranosyl LinkageGyörgy Hodosi Pavol KováčView Author Information NIDDK, Section on Carbohydrates, LMC National Institutes Health Bethesda, Maryland 20892-0815 Cite this: J. Am. Chem. Soc. 1997, 119, 9, 2335–2336Publication Date (Web):March 5, 1997Publication History Received20 November 1996Published online5 March...
Abstract Using photogenerated glycan arrays, we characterized a large panel of synthetic carbohydrates for their antigenic reactivities with pathogen‐specific antibodies. We discovered that rabbit IgG antibodies elicited by Bacillus anthracis spores specifically recognize tetrasaccharide chain decorates the outermost surfaces B. exosporium. Since this sugar moiety is highly specific , it appears to be key biomarker detection and development novel vaccines target anthrax spores.
The combination of liquid hydrogen and superconducting cables presents a unique opportunity to distribute both bulk electricity in the same infrastructure. In particular, around 20 K is ideally suited for cooling MgB <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> superconductor, resulting compact power cable that also leaves sufficient place flow. Such hybrid system operating MVDC range at 25 kV kA constitutes one main goals European...
We have developed a 150°C technology for amorphous silicon thin-film transistors ͑a-Si:H TFTs͒ on polyimide substrates deposited by plasma enhanced chemical vapor deposition.The nitride gate dielectric and the a-Si:H channel material were tailored to provide least leakage current midgap defect density, respectively.In addition, we conducted experiments TFT structure fabrication with aim of obtaining high electron mobility.TFTs back-channel etch channelpassivated structures fabricated glass...
Offshore wind market demands higher power rate and reliable turbines in order to optimize capital operational cost. These requests are difficult overcome with conventional generator technologies due a significant weight cost increase the scaling up. Thus superconducting materials appears as prominent solution for generators, based on their capacity held high current densities very small losses, which permits efficiently replace copper conductors mainly rotor field coils. However...
Abstract Superconducting joints between single-core MgB2/Fe wires made by ex-situ Powder-in-Tube (PIT) process were manufactured using scarf joint architecture. MgB2 powder of variable particles and different deforming ratio applied for the set annealed finally at 950 oC/30 min. The critical transport currents measured 4.2 K external magnetic fields up to 6 T compared with not joined wires. Structure interfaces analysed optical microscopy. joint’s current is dominantly affected deformation...
Abstract Low temperature properties of 49-strand circular cables made ultrafine NIMS MgB2 wires has been studied. Critical currents from single-core diameter 0.050 mm and 0.022 different sheath material (Cu, CuNi Monel) have measured at temperatures 4.2 – 35 K external fields 0 8 T. In addition, magnetization AC losses were 20 45 K, 1 100 mT frequencies 72 Hz 144 Hz. The presented experimental results show high engineering current densities in spite very low filament size 8.5 µm also due to...
Abstract The efficacy of MgB 2 -based cables for DC power transmission applications is well-established due to several advantageous properties such as the natural abundance and cost-effectiveness precursor powders innate compatibility with liquid hydrogen, which has a boiling point 20 K. Notably, critical temperature T c 39 However, transitioning this technology AC applications, like electric motors or transmission, poses challenges primarily material’s susceptibility losses when subjected...
Single- and four-core MgB2 wires have been made by the powder-in-tube (PIT) method using a commercial powder (Alfa Aesar) two-axial rolling deformation in an Fe sheath. The deformed were subjected to annealing at temperatures from 950 °C up 1100 for 30 minutes argon. interface layer thickness of 10–25.4 μm caused inter-diffusion reaction between core sheath has observed all annealed wires. Transport currents as-deformed post-annealed measured temperature 4.2 K external magnetic field B =...
Superconducting MgB2 wires have been made by powder-in-tube (PIT) processing of commercial powder in Fe, stainless steel and composite metallic sheaths using annealing temperatures from 850 to 1100 °C. Technologically interesting Jc values around 106 A cm−2 the self-field at 4.2 K achieved. However, as temperature is increased, substantial chemical reactions observed MgB2/sheath interface. We report on a detailed study electron probe microanalysis reaction products interfacial region...
Single-core MgB2 composite wires have been made by the powder-in-tube method using commercial Mg, B and powders (Alfa Aesar) in Fe, Nb Ta tubes both situ ex processes. Prepared were subjected to annealing at temperatures ranging from 600 °C up 950 for 30 min argon atmosphere. Resistive (R(T)) transport current (Ic(μ0H)) measurements shown how sheath material that was used influences critical temperature density. Inter-diffusion reaction has observed only iron sheath. Niobium appeared as best...
The thermal stability of different Fe-and Ni-sheathed MgB2 conductors has been studied experimental and numerically, focusing on the estimation quench propagation velocities, vp, minimum energies (MQE) propagating zones (MPZ).The measurements have done at self-field under adiabatic conditions, variable temperatures transport currents.Energy pulses were deposited to conductor by passing rectangular current through a graphite-based-epoxy heater.The measured voltage around heater together with...
In situ nano-SiC doped MgB2 wires were fabricated from MgH2 and B powders. Hydrostatic extrusion, followed by rotary swaging two-axial rolling, applied as the forming processes. The critical current Jc of wires, made powders, was significantly improved doping. Nano-SiC doping substantially increased upper (irreversibility) field Bc 2 above 20 T. maximum values measured for samples having 6 at.% SiC in low those 12 high field, 10 During final sintering at 670 °C, decomposed formed an Si-rich...
The phase evolution inside Fe-sheathed wires containing precursor powders consisting of a mixture Mg and B has been studied in situ by means x-ray diffraction with hard synchrotron radiation (90 keV). was found to disappear progressively during the heating stage. At 500 °C, intensity lines is reduced about 20%. This effect partly attributable MgO formation. MgB2 detected from 575 °C. Fe2B forming at interface between sheath ceramic core sintering temperatures 780 700 but not 650 formation...
Stabilized four-filament in situ MgB2/Ti/Cu/Monel composite wire was produced by the rectangular wire-in-tube (RWIT) technique. 10 wt% of nanosize SiC added into Mg–B powder mixture, which packed Ti/Cu and Monel tubes, respectively. The assembled two-axially rolled and/or tape form sintered at temperatures 650–850 °C/0.5 h. MgB2 with Ti barrier is studied terms field-dependent transport critical current density, effects filament size reduction thermal stability.
The current transfer length in composite MgB2 wires with different metallic sheaths and filament numbers was analysed. electric potential gradient along the wire vicinity of contact monitored as a function transport various external magnetic fields up to 14 T. In all samples characteristic is order millimetre, varying detailed sheath composition range 0.35–2 mm. For clear reaction layer at filament/matrix interface, electrical resistivity material constituting such barrier estimated.
Multi-core MgB2 wire reinforced by stainless steel (SS) has been made an in situ approach and subjected to additional deformations mechanical stressing. A critical current density Jc of 104 cm − 2 at 4.2 K was measured external field 9.45–10 T. The filament drawn increased cold deformation without axial tension, which resulted approximately 17%. SS shows a high resistance stresses. Only 10% Ic degradation for twisted with Lt = 7.14 mm. presented the highest irreversible strain εirr 0.9% so...
Single- and four-core MgB2 wires have been manufactured by internal magnesium diffusion (IMD) into boron. Initial hydrostatic extrusion was applied for single-core Cu sheathed wire mostly rolling deformation assembled with Inconel or GlidCop sheath. The highest critical current density (Jc) measured the boron densified cold isostatic pressing 1.9 GPa. Rolled tapes exhibited anisotropy increasing tape's aspect ratio. Low degradation of IMD twisting has observed, which can be utilized...