645 research outputs found
Spark Plasma Sintering of Boron Carbide Powder
The results presented in this article demonstrate that boron carbide ceramics of a perfect microstructure, of a high density (up to 99.8%) and microhardness (36.1 GPa) can be made from the industrial micron fraction powder thanks to spark plasma sintering, that opens prospects for wide SPS application in economical production of high-quality boron carbide ceramic products. Optimal ceramics production mode is based on B4C (technical powder), which makes the best combination of physical and mechanical properties and uniformmicrostructure. The experimentally set mode of spark-plasma sintering of highdensity B4C ceramics allows to lower the sintering temperature by 300 βC and to shorten the process time by 20 minutes relative to the corresponding values when traditional hot pressing.
Keywords: spark - plasma sintering, boron carbide, densit
Calculation of thermal parameters of SiGe microbolometers
The thermal parameters of a SiGe microbolometer were calculated using
numerical modeling. The calculated thermal conduction and thermal response time
are in good agreement with the values found experimentally and range between
2x10 and 7x10 W/K and 1.5 and 4.5 ms, respectively. High sensitivity
of microbolometer is achieved due to optimization of the thermal response time
and thermal conduction by fitting the geometry of supporting heat-removing legs
or by selection of a suitable material providing boundary thermal resistance
higher than 8x10 cmK/W at the SiGe interface.Comment: 11 pages, 6 figure
Coherent spin dynamics of electrons and holes in CsPbBr perovskite crystals
The lead halide perovskites demonstrate huge potential for optoelectronic
applications, high energy radiation detectors, light emitting devices and solar
energy harvesting. Those materials exhibit strong spin-orbit coupling enabling
efficient optical orientation of carrier spins in perovskite-based devices with
performance controlled by a magnetic field. Perovskites are promising for
spintronics due to substantial bulk and structure inversion asymmetry, however,
their spin properties are not studied in detail. Here we show that elaborated
time-resolved spectroscopy involving strong magnetic fields can be successfully
used for perovskites. We perform a comprehensive study of high-quality
CsPbBr crystals by measuring the exciton and charge carrier -factors,
spin relaxation times and hyperfine interaction of carrier and nuclear spins by
means of coherent spin dynamics. Owing to their "inverted" band structure,
perovskites represent appealing model systems for semiconductor spintronics
exploiting the valence band hole spins, while in conventional semiconductors
the conduction band electrons are considered for spin functionality.Comment: 8 pages, 3 figures + supplementary informatio
Group analysis and renormgroup symmetries
An original regular approach to constructing special type symmetries for
boundary value problems, namely renormgroup symmetries, is presented. Different
methods of calculating these symmetries, based on modern group analysis are
described. Application of the approach to boundary value problems is
demonstrated with the help of a simple mathematical model.Comment: 17 pages, RevTeX LATeX file, to appear in Journal of Mathematical
Physic
Influence of plasma volume discharge in atmospheric-pressure air on the admittance of MIS structures based on MBE p-HgCdTe
This article investigates the effect of a nanosecond plasma volume discharge, which is formed in an inhomogeneous electrical field at atmospheric pressure, on the electrical properties of MIS structures based on HgCdTe (MCT) epitaxial films. The MIS structure based on films exposed to the discharge significantly changed its main parameters. The most notable feature of the structure exposed to discharge is the significant increase in the positive fixed charge in the insulator. A possible reason for changes in the characteristics of MIS structure after exposure to discharge is the significant change in the impurity-defect system of the semiconductor near the interface. This is accompanied with a formation of an insulator film of nanometer thickness on the surface, which gives rise to positive fixed charge
ΠΡΠΎΠ±Π΅Π½Π½ΠΎΡΡΠΈ ΡΠ΅ΡΠ»Π΅ΠΊΡΠΎΡΠ½ΠΎΠΉ ΡΠ΅Π³ΡΠ»ΡΡΠΈΠΈ ΠΊΠ°ΡΠ΄ΠΈΠΎΡΠ΅ΡΠΏΠΈΡΠ°ΡΠΎΡΠ½ΠΎΠΉ ΡΠΈΡΡΠ΅ΠΌΡ ΠΏΡΠΈ Π±Π΅ΡΠ΅ΠΌΠ΅Π½Π½ΠΎΡΡΠΈ: ΡΠΈΡΡΠ΅ΠΌΠ°ΡΠΈΡΠ΅ΡΠΊΠΈΠΉ ΠΎΠ±Π·ΠΎΡ Π»ΠΈΡΠ΅ΡΠ°ΡΡΡΡ
ΠΠΠ’Π£ΠΠΠ¬ΠΠΠ‘Π’Π¬: ΠΡΠ°ΡΡΒ β Π°Π½Π΅ΡΡΠ΅Π·ΠΈΠΎΠ»ΠΎΠ³Ρ-ΡΠ΅Π°Π½ΠΈΠΌΠ°ΡΠΎΠ»ΠΎΠ³Ρ ΠΏΡΠΈ ΡΠΎΡΡΠ°Π²Π»Π΅Π½ΠΈΠΈ ΠΏΠ»Π°Π½Π° Π°Π½Π΅ΡΡΠ΅Π·ΠΈΠΎΠ»ΠΎΠ³ΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ ΠΎΠ±Π΅ΡΠΏΠ΅ΡΠ΅Π½ΠΈΡ ΠΎΠΏΠ΅ΡΠ°ΡΠΈΠΈ ΠΊΠ΅ΡΠ°ΡΠ΅Π²Π° ΡΠ΅ΡΠ΅Π½ΠΈΡ Π½Π΅ΠΎΠ±Ρ
ΠΎΠ΄ΠΈΠΌΠΎ Π·Π½Π°ΡΡ ΠΎΒ ΡΠΎΠΌ, ΠΊΠ°ΠΊΠΈΠ΅ ΡΠΈΠ·ΠΈΠΎΠ»ΠΎΠ³ΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΠΈΒ ΡΡΠ½ΠΊΡΠΈΠΎΠ½Π°Π»ΡΠ½ΡΠ΅ ΠΎΡΠΎΠ±Π΅Π½Π½ΠΎΡΡΠΈ ΠΈΠΌΠ΅Π΅Ρ Π±Π΅ΡΠ΅ΠΌΠ΅Π½Π½Π°Ρ ΠΏΠ°ΡΠΈΠ΅Π½ΡΠΊΠ° Π²Β ΡΠΎΠΌ ΠΈΠ»ΠΈ ΠΈΠ½ΠΎΠΌ ΡΡΠΎΠΊΠ΅ Π³Π΅ΡΡΠ°ΡΠΈΠΈ. ΠΡΠ°Π²ΠΈΠ»ΡΠ½ΠΎΠ΅ ΡΠΎΡΡΠ°Π²Π»Π΅Π½ΠΈΠ΅ ΠΏΠ»Π°Π½Π° Π°Π½Π΅ΡΡΠ΅Π·ΠΈΠΈ ΠΈΒ ΡΠ°ΠΊΡΠΈΠΊΠΈ Π²Π΅Π΄Π΅Π½ΠΈΡ ΠΏΠ°ΡΠΈΠ΅Π½ΡΠΎΠΊ Π²Β ΠΏΠ΅ΡΠΈΠΎΠΏΠ΅ΡΠ°ΡΠΈΠΎΠ½Π½ΠΎΠΌ ΠΏΠ΅ΡΠΈΠΎΠ΄Π΅ ΠΏΠΎΠΌΠΎΠ³Π°Π΅Ρ ΡΠ½ΠΈΠ·ΠΈΡΡ ΡΠΈΡΠΊ Π³Π΅ΠΌΠΎΠ΄ΠΈΠ½Π°ΠΌΠΈΡΠ΅ΡΠΊΠΈΡ
, ΡΠ΅ΡΠΏΠΈΡΠ°ΡΠΎΡΠ½ΡΡ
ΠΈΒ Π΄ΡΡΠ³ΠΈΡ
ΠΊΡΠΈΡΠΈΡΠ΅ΡΠΊΠΈΡ
ΠΈΠ½ΡΠΈΠ΄Π΅Π½ΡΠΎΠ². Π¦ΠΠΠ¬ ΠΠ‘Π‘ΠΠΠΠΠΠΠΠΠ―: ΠΠΎΠΈΡΠΊ Π΄Π°Π½Π½ΡΡ
ΠΎΒ ΡΠΏΠΎΡΠΎΠ±Π°Ρ
ΠΈΒ ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΠ°Ρ
ΠΎΡΠ΅Π½ΠΊΠΈ ΠΊΠ°ΡΠ΄ΠΈΠΎΡΠ΅ΡΠΏΠΈΡΠ°ΡΠΎΡΠ½ΠΎΠ³ΠΎ ΡΡΠ°ΡΡΡΠ° Π±Π΅ΡΠ΅ΠΌΠ΅Π½Π½ΡΡ
ΡΒ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΠ΅ΠΌ ΠΌΠ΅ΡΠΎΠ΄ΠΎΠ², Π·Π°Π΄Π΅ΠΉΡΡΠ²ΡΡΡΠΈΡ
ΡΠ°ΠΊΠΈΠ΅ ΠΊΠ»ΡΡΠ΅Π²ΡΠ΅ ΠΌΠ΅Ρ
Π°Π½ΠΈΠ·ΠΌΡ ΡΠ΅ΡΠ»Π΅ΠΊΡΠΎΡΠ½ΠΎΠΉ ΡΠ΅Π³ΡΠ»ΡΡΠΈΠΈ, ΠΊΠ°ΠΊ Π°ΡΡΠ΅ΡΠΈΠ°Π»ΡΠ½ΡΠΉ Π±Π°ΡΠΎΡΠ΅ΡΠ»Π΅ΠΊΡ (ΠΠΠ ) ΠΈΒ ΠΏΠ΅ΡΠΈΡΠ΅ΡΠΈΡΠ΅ΡΠΊΠΈΠΉ Ρ
Π΅ΠΌΠΎΡΠ΅ΡΠ»Π΅ΠΊΡ (ΠΠ₯Π ). ΠΠΠ’ΠΠ ΠΠΠΠ« Π ΠΠΠ’ΠΠΠ«: ΠΡ ΠΏΡΠΎΠ²Π΅Π»ΠΈ ΡΠΈΡΡΠ΅ΠΌΠ°ΡΠΈΡΠ΅ΡΠΊΠΈΠΉ ΠΎΠ±Π·ΠΎΡ Π»ΠΈΡΠ΅ΡΠ°ΡΡΡΡ Π²Β ΡΠΎΠΎΡΠ²Π΅ΡΡΡΠ²ΠΈΠΈ ΡΒ ΡΠ΅ΠΊΠΎΠΌΠ΅Π½Π΄Π°ΡΠΈΡΠΌΠΈ PRISMA. ΠΠΎΠΈΡΠΊ Π±ΡΠ» ΠΏΡΠΎΠ²Π΅Π΄Π΅Π½ Π²Β Π΄Π΅ΠΊΠ°Π±ΡΠ΅ 2022Β Π³. Π²Β Π±Π°Π·Π°Ρ
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Π΅ΠΌΠΎΡΠ΅ΡΠ»Π΅ΠΊΡ Π±Π΅ΡΠ΅ΠΌΠ΅Π½Π½ΠΎΡΡΡΒ», Β«Π±Π°ΡΠΎΡΠ΅ΡΠ»Π΅ΠΊΡ Π±Π΅ΡΠ΅ΠΌΠ΅Π½Π½ΠΎΡΡΡΒ», Β«ΠΏΡΠΎΠ±Π° ΠΠ°Π»ΡΡΠ°Π»ΡΠ²Ρ Π±Π΅ΡΠ΅ΠΌΠ΅Π½Π½ΠΎΡΡΡΒ», Β«pregnancy breath holding testΒ», Β«pregnancy chemoreflexΒ», Β«pregnancy baroreflexΒ», Β«Valsalva test pregnancyΒ». Π ΠΠΠ£ΠΠ¬Π’ΠΠ’Π«: ΠΡΠ»ΠΎ Π½Π°ΠΉΠ΄Π΅Π½ΠΎ 110Β ΡΠ°Π±ΠΎΡ, ΠΏΠΎΡΠ»Π΅ ΡΠ΄Π°Π»Π΅Π½ΠΈΡ ΠΏΠΎ ΡΠ°Π·Π»ΠΈΡΠ½ΡΠΌ ΠΏΡΠΈΡΠΈΠ½Π°ΠΌ 68Β ΡΠ°Π±ΠΎΡ Π±ΡΠ»ΠΎ ΠΏΡΠΎΠ°Π½Π°Π»ΠΈΠ·ΠΈΡΠΎΠ²Π°Π½ΠΎ 42Β ΠΏΠΎΠ»Π½ΠΎΡΠ΅ΠΊΡΡΠΎΠ²ΡΡ
ΠΈΡΡΠΎΡΠ½ΠΈΠΊΠ°, Π²Β ΡΠΎΠΌ ΡΠΈΡΠ»Π΅ ΠΏΡΠΎΠ²Π΅Π΄Π΅Π½ ΠΏΠΎΠ΄ΡΠΎΠ±Π½ΡΠΉ ΡΡΠ°Π²Π½ΠΈΡΠ΅Π»ΡΠ½ΡΠΉ Π°Π½Π°Π»ΠΈΠ· 8Β ΠΈΡΡΠΎΡΠ½ΠΈΠΊΠΎΠ², ΠΏΠΎΠ»Π½ΠΎΡΡΡΡ ΡΠΎΠΎΡΠ²Π΅ΡΡΡΠ²ΡΡΡΠΈΡ
ΠΊΡΠΈΡΠ΅ΡΠΈΡΠΌ Π²ΠΊΠ»ΡΡΠ΅Π½ΠΈΡ. ΠΠΈΠ·Π°ΠΉΠ½, ΡΠ΅Π»ΠΈ, ΠΌΠ΅ΡΠΎΠ΄Ρ, Π΄ΠΎΡΡΡΠΏΠ½ΠΎΡΡΡ Π΄Π°Π½Π½ΡΡ
ΠΈΒ ΠΊΠΎΠ½Π΅ΡΠ½ΡΠ΅ ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΡ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΠΉ Π±ΡΠ»ΠΈ Π½Π΅ΠΎΠ΄Π½ΠΎΡΠΎΠ΄Π½ΡΠΌΠΈ, ΠΏΠΎΡΡΠΎΠΌΡ ΠΌΠ΅ΡΠ°Π°Π½Π°Π»ΠΈΠ· Π΄Π°Π½Π½ΡΡ
Π½Π΅ ΠΏΡΠΎΠ²ΠΎΠ΄ΠΈΠ»ΡΡ. ΠΡΠ»ΠΈ ΠΈΠ·Π²Π»Π΅ΡΠ΅Π½Ρ ΠΈΒ ΠΎΠ±ΠΎΠ±ΡΠ΅Π½Ρ Π΄Π°Π½Π½ΡΠ΅ ΠΎΒ ΡΡΠ½ΠΊΡΠΈΠΎΠ½Π°Π»ΡΠ½ΡΡ
ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΡΡ
Π²Β ΡΠ°Π±ΠΎΡΠ΅ ΠΊΠ°ΡΠ΄ΠΈΠΎΡΠ΅ΡΠΏΠΈΡΠ°ΡΠΎΡΠ½ΠΎΠΉ ΡΠΈΡΡΠ΅ΠΌΡ, ΠΏΡΠΎΠΈΡΡ
ΠΎΠ΄ΡΡΠΈΡ
ΠΏΡΠΈ Π±Π΅ΡΠ΅ΠΌΠ΅Π½Π½ΠΎΡΡΠΈ ΠΈΒ ΠΎΡΡΠ°ΠΆΠ°ΡΡΠΈΡ
ΡΡ Π²Β ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΠΈ ΡΡΠ²ΡΡΠ²ΠΈΡΠ΅Π»ΡΠ½ΠΎΡΡΠΈ ΠΠΠ ΠΈΒ ΠΠ₯Π . ΠΠ«ΠΠΠΠ«: Π§ΡΠ²ΡΡΠ²ΠΈΡΠ΅Π»ΡΠ½ΠΎΡΡΡ ΠΠ₯Π ΡΒ Π±Π΅ΡΠ΅ΠΌΠ΅Π½Π½ΡΡ
ΠΌΠΎΠΆΠ½ΠΎ ΠΎΡΠ΅Π½ΠΈΠ²Π°ΡΡ ΡΒ ΠΏΠΎΠΌΠΎΡΡΡ Π²Π΄ΡΡ
Π°Π½ΠΈΡ Π³ΠΈΠΏΠ΅ΡΠΎΠΊΡΠΈΡΠ΅ΡΠΊΠΎΠΉ, Π³ΠΈΠΏΠ΅ΡΠΊΠ°ΠΏΠ½ΠΈΡΠ΅ΡΠΊΠΎΠΉ ΠΈΒ ΠΈΠ·ΠΎΠΎΠΊΡΠΈΡΠ΅ΡΠΊΠΈ-Π³ΠΈΠΏΠ΅ΡΠΊΠ°ΠΏΠ½ΠΈΡΠ΅ΡΠΊΠΎΠΉ Π³Π°Π·ΠΎΠ²ΠΎΠΉ ΡΠΌΠ΅ΡΠΈ (Π²Π°ΡΠΈΠ°Π½ΡΡ ΠΏΡΠΎΠ±Ρ ΡΒ Π²ΠΎΠ·Π²ΡΠ°ΡΠ½ΡΠΌ Π΄ΡΡ
Π°Π½ΠΈΠ΅ΠΌ). Π§ΡΠ²ΡΡΠ²ΠΈΡΠ΅Π»ΡΠ½ΠΎΡΡΡ ΠΠΠ ΡΒ Π±Π΅ΡΠ΅ΠΌΠ΅Π½Π½ΡΡ
ΠΌΠΎΠΆΠ½ΠΎ ΠΎΡΠ΅Π½ΠΈΠ²Π°ΡΡ ΡΒ ΠΏΠΎΠΌΠΎΡΡΡ ΡΠ΅Π½ΠΈΠ»ΡΡΡΠΈΠ½ΠΎΠ²ΠΎΠ³ΠΎ ΡΠ΅ΡΡΠ° ΠΏΡΠΎΠ±Ρ ΠΠ°Π»ΡΡΠ°Π»ΡΠ²Ρ, ΠΎΡΡΠΎΡΡΠ°ΡΠΈΡΠ΅ΡΠΊΠΎΠΉ ΠΏΡΠΎΠ±Ρ, Π°Β ΡΠ°ΠΊΠΆΠ΅ ΡΠΏΠ΅ΠΊΡΡΠ°Π»ΡΠ½ΠΎΠ³ΠΎ Π°Π½Π°Π»ΠΈΠ·Π° ΠΏΠΎΡΠ»Π΅Π΄ΠΎΠ²Π°ΡΠ΅Π»ΡΠ½ΠΎΡΡΠ΅ΠΉ Π·Π½Π°ΡΠ΅Π½ΠΈΠΉ Π°ΡΡΠ΅ΡΠΈΠ°Π»ΡΠ½ΠΎΠ³ΠΎ Π΄Π°Π²Π»Π΅Π½ΠΈΡ ΠΈΒ ΠΈΠ½ΡΠ΅ΡΠ²Π°Π»Π° RβR. Π§ΡΠ²ΡΡΠ²ΠΈΡΠ΅Π»ΡΠ½ΠΎΡΡΡ ΠΠ₯Π ΠΏΡΠΈ Π΄ΠΎΠ½ΠΎΡΠ΅Π½Π½ΠΎΠΉ Π±Π΅ΡΠ΅ΠΌΠ΅Π½Π½ΠΎΡΡΠΈ ΡΠ²Π΅Π»ΠΈΡΠΈΠ²Π°Π΅ΡΡΡ. Π§ΡΠ²ΡΡΠ²ΠΈΡΠ΅Π»ΡΠ½ΠΎΡΡΡ ΠΠΠ ΡΒ Π±Π΅ΡΠ΅ΠΌΠ΅Π½Π½ΡΡ
ΠΏΡΠΎΠ³ΡΠ΅ΡΡΠΈΠ²Π½ΠΎ ΡΠ½ΠΈΠΆΠ°Π΅ΡΡΡ ΠΎΡ Π½Π°ΡΠ°Π»Π° Π±Π΅ΡΠ΅ΠΌΠ΅Π½Π½ΠΎΡΡΠΈ Π΄ΠΎ ΠΊΠΎΠ½ΡΠ° IIΒ ΡΡΠΈΠΌΠ΅ΡΡΡΠ° ΠΈΒ ΠΏΠΎΠ²ΡΡΠ°Π΅ΡΡΡ Π²Β ΠΏΠΎΡΠ»Π΅ΡΠΎΠ΄ΠΎΠ²ΠΎΠΌ ΠΏΠ΅ΡΠΈΠΎΠ΄Π΅ Π΄ΠΎ ΠΈΡΡ
ΠΎΠ΄Π½ΠΎΠ³ΠΎ ΡΡΠΎΠ²Π½Ρ; Π²Β IIIΒ ΡΡΠΈΠΌΠ΅ΡΡΡΠ΅ Π±Π΅ΡΠ΅ΠΌΠ΅Π½Π½ΠΎΡΡΠΈ ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΡ ΡΡΠ²ΡΡΠ²ΠΈΡΠ΅Π»ΡΠ½ΠΎΡΡΠΈ ΠΠΠ Π½ΠΎΡΡΡ ΠΈΠ½Π΄ΠΈΠ²ΠΈΠ΄ΡΠ°Π»ΡΠ½ΡΠΉ Ρ
Π°ΡΠ°ΠΊΡΠ΅Ρ ΠΈΒ Π½Π΅ ΠΈΠΌΠ΅ΡΡ Π΅Π΄ΠΈΠ½ΠΎΠΉ ΡΠ΅Π½Π΄Π΅Π½ΡΠΈΠΈ
Influence of pulsed nanosecond volume discharge in atmospheric-pressure air on the electrical characteristics of MCT epitaxial films
The purpose of this paper was investigating the effect of volume nanosecond discharge in air at atmospheric pressure on the electro-physical properties of the HgCdTe (MCT) epitaxial films grown by molecular beam epitaxy. Hall measurements of electro-physical parameters of MCT samples after irradiation have shown that there is a layer of epitaxial films exhibiting n-type conductivity that is formed in the near-surface area. After more than 600 pulses of influence parameters and thickness of the resulting n-layer is such that the measured field dependence of Hall coefficient corresponds to the material of n-type conductivity. Also it is shown that the impact of the discharge leads to significant changes in electro-physical characteristics of MIS structures. This fact is demonstrated by increase in density of positive fixed charge, change in the hysteresis type of the capacitance-voltage characteristic, an increase in density of surface states. The preliminary results show that it is possible to use such actions in the development of technologies of the controlled change in the properties of MCT. Β© (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only
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