High-entropy alloys are promising materials for novel thin-film resistors since they have high resistivity and a low-temperature coefficient of resistivity (TCR). In this work, a new high-entropy thin-film CoCrFeNiTi was deposited on a Si/SiO substrate by means of magnetron sputtering of the multi-component target produced by hot pressing of the powder mixture. The samples possessed a thickness of 130-230 nm and an amorphous atomic structure with nanocrystallite traces.
View Article and Find Full Text PDFChalcogenide vitreous semiconductors (ChVSs) find application in rewritable optical memory storage and optically switchable infrared photonic devices due to the possibility of fast and reversible phase transitions, as well as high refractive index and transmission in the near- and mid-infrared spectral range. Formed on such materials, laser-induced periodic surface structures (LIPSSs), open wide prospects for increasing information storage capacity and create polarization-sensitive optical elements of infrared photonics. In the present work, a possibility to produce LIPSSs under femtosecond laser irradiation (pulse duration 300 fs, wavelength 515 nm, repetition rate up to 2 kHz, pulse energy ranged 0.
View Article and Find Full Text PDFIn this study, hard wear-resistant Ti-Si-C coatings were deposited on Cu-Cr materials to improve their performance as sliding electrical contact materials. A ceramic disk composed of TiSiC and TiC phases was used as a target for DC magnetron sputtering to deposit the coatings. The influence of the power supplied to the magnetron on the chemical composition, structure, and friction coefficient of the coatings was examined.
View Article and Find Full Text PDFThe characteristics of the absolute auditory sensitivity of the bottlenose dolphin (Tursiops truncatus p.) in the transverse plane have been measured using short broad-band stimuli simulating dolphin clicks (with energy maximum at frequencies 8, 16, 30, 50 and 100 kHz). Experiments were performed using the method of conditioned reflexes with food reinforcement.
View Article and Find Full Text PDFThe accuracy of localizing the underwater sound source in the vertical-plane by the bottlenose dolphin was investigated using the method of instrumental conditioned reflexes with food reinforcement. The accuracy of determining the underwater sound in the vertical plane (the full angle) was on the average: 2 - 2,5 degrees for tonal signals with frequencies of 5, 20, and 120 kHz; pulsed clicks with the central frequency of 120 kHz and the exponential forms of amplitude alteration wavefronts were localized by the dolphin with an accuracy of 1,5 degrees. Among all marine mammals examined, dolphins are characterized by the maximal exact analysis of acoustic space.
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