112 research outputs found
Considerable enhancement of the critical current in a superconducting film by magnetized magnetic strip
We show that a magnetic strip on top of a superconducting strip magnetized in
a specified direction may considerably enhance the critical current in the
sample. At fixed magnetization of the magnet we observed diode effect - the
value of the critical current depends on the direction of the transport
current. We explain these effects by a influence of the nonuniform magnetic
field induced by the magnet on the current distribution in the superconducting
strip. The experiment on a hybrid Nb/Co structure confirmed the predicted
variation of the critical current with a changing value of magnetization and
direction of the transport current.Comment: 6 pages, 7 figure
Ligand Exchange Reactions and Hydroamination with Tris(oxazolinyl)borato Yttrium Compounds
DPF device application in the material characterization
The ability of a dense plasma focus (DPF) installation, to serve as a unique powerful hard X-ray and neutron pulse generator, is discussed. A principle of the dynamic detection of defects, based on a small-scale DPF device, is described. The results of a dynamic defect detection experiment are presented. Different aspects of the application and adaptation of a small DPF chamber for the material science, are discussed
Structure and Mechanical Properties of Titanium Processed by Twist Extrusion and Subsequent Rolling
The article considers one of the combined methods of severe plastic deformation (SPD), which includes twist extrusion (TE) and subsequent rolling. The use of combined forming methods is promising for industrial use. Titanium grade 1 was used as a material in the experiments. Rolling was carried out in three stages with a decrease in temperature from 350°C to 180°C for a number of passes with one heating. The accumulated strain degree was e = 4.6 at twist extrusion and e = 3 in rolling. Increasing the reduction per pass decreases the number of heatings and increases the efficiency of the rolling process in whole. At the same time, it is necessary to set the maximum processing modes at which recrystallization processes do not occur in the billet. When rolling, the deformation degree in one pass was taken in the range of 5–20% with an increase in successive passes. The use of such deformation degrees allowed reducing the grain size in titanium grade 1 significantly. Twist extrusion reduces the grain size to 300–500 nm. Subsequent rolling allowed reducing the size of structural elements to 50–100 nm and provided a significant increase in the mechanical characteristics of the billet material (up to 869 MPa) while maintaining satisfactory ductility (up to 11.6%). It was found that increasing the deformation degree in one pass up to 40% at cross-rolling and simultaneously increasing the temperature to 385°C led to a decrease in the UFG structure quality and reduced strength of the deformable material by starting the dynamic recrystallization process
Damage of Al2O3 ceramics under the action of pulsed ion and plasma fluxes and laser irradiation
Multicomputer system dedal-2 for local landscape monitoring
The paper contains the description of a multicomputer system for terrestrial surface automatized monitoring. The system is able to detect moving objects on the terrain considered, to locate static objects which appear/disappear on terrain as well as to recognize such objects. The system uses photosnapshot the terrain and a set of reference images for recognition
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