696 research outputs found
Measurement of young's modulus and hardness of Al-50 wt % Sn alloy phases using nanoindentation
The nanoindentation method was used to measure the Young's modulus and hardness of the phases of the alloy Al-50 wt % Sn: Ξ±-aluminum and eutectic. Samples are obtained in different ways, i.e., traditionally via the transition of the melt into a homogeneous structural state by heating to a certain temperature, followed by cooling using the cooling rate greater by the order than that of the traditional method and via the addition of 0.06 wt % Ti and 1 wt % Zr to the binary alloy. It has been found that the most significant effect of the Al-50 wt % Sn phases on the Young's modulus is the transition of the melt into a homogeneous structural state and the introduction of Zr into the melt. As part of the mathematical theory of elasticity, a numerical evaluation of the interfacial pressure that arises due to the difference between Young's modulus of Ξ± aluminum and eutectic has been performed. The calculation has showed that the extra pressure is nine times less for the alloy formed through the transition of the melt into a homogeneous structural state than for the alloy produced via a traditional way. Β© 2013 Pleiades Publishing, Ltd
Polarization reversal and jump-like domain wall motion in stoichiometric LiTaO 3 produced by vapor transport equilibration
The polarization reversal and domain structure evolution has been studied in stoichiometric lithium tantalate prepared by vapor transport equilibration process. The first in situ visualization of domain kinetics has demonstrated the jump-like motion of few strictly oriented plane domain walls, which leads to short isolated current pulses in the switching current data. The proposed model of jump-like domain wall motion caused by interaction with pinning centers representing the areas with increased value of the threshold field is based on the effect of retardation of bulk screening. The derived formulas were applied successfully for analysis of the field dependence of the total switching time. The durations of wall jumps and wall stays (rest times) extracted from the switching current data are analyzed separately. The deceleration of the wall motion velocity during jump is controlled by the trail of residual depolarization field produced by bound charges and screening charges in the area behind the wall. The duration of the rest time is governed by the bulk screening of residual depolarization field. The value of Hurst exponent 0.75 obtained by fractal analysis of the switching current data has confirmed the essential influence of prehistory on the domain wall motion. The measurements of the coercive field by switching in bipolar triangular pulses in wide range of the field ramp rate have allowed us to extract the record low value of coercive field 60 V/mm for quasi-static polarization reversal. Β© 2012 American Institute of Physics
ΠΠ°ΡΠ½Π°Π²Π°Π»ΡΠ½ΡΠΉ Ρ Π°ΡΠ°ΠΊΡΠ΅Ρ ΡΠΎΠ²ΡΠ΅ΠΌΠ΅Π½Π½ΠΎΠΉ Π°ΠΌΠ΅ΡΠΈΠΊΠ°Π½ΡΠΊΠΎΠΉ Π°Π΄ΠΌΠΈΠ½ΠΈΡΡΡΠ°ΡΠΈΠΈ Π²ΡΠ΅ΠΌΠ΅Π½ Π. Π’ΡΠ°ΠΌΠΏΠ° ΠΈ Π. ΠΠ°ΠΉΠ΄Π΅Π½Π°
Π ΡΡΠ°ΡΡΠ΅ ΡΠ°ΡΡΠΌΠ°ΡΡΠΈΠ²Π°ΡΡΡΡ Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠ½ΡΠ΅ ΠΎΡΠΎΠ±Π΅Π½Π½ΠΎΡΡΠΈ Π°ΠΌΠ΅ΡΠΈΠΊΠ°Π½ΡΠΊΠΎΠΉ Π°Π΄ΠΌΠΈΠ½ΠΈΡΡΡΠ°ΡΠΈΠΈ Π² ΠΊΠΎΠ½ΡΠ΅ΠΊΡΡΠ΅ ΠΊΠ°ΡΠ½Π°Π²Π°Π»ΡΠ½ΠΎΠΉ ΠΏΠΎΠ»ΠΈΡΠΈΠΊΠΈ. ΠΡΠΎΠ²ΠΎΠ΄ΠΈΡΡΡ Π°Π½Π°Π»ΠΈΠ· Π²ΡΡΠΊΠ°Π·ΡΠ²Π°Π½ΠΈΠΉ ΠΊΠ°ΠΊ ΠΊΠ»ΡΡΠ΅Π²ΡΡ
ΡΠΈΠ³ΡΡ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ ΠΠΎΠ½Π°Π»ΡΠ΄Π° Π’ΡΠ°ΠΌΠΏΠ° ΠΈ ΠΠΆΠΎ ΠΠ°ΠΉΠ΄Π΅Π½Π°, ΡΠ°ΠΊ ΠΈ ΠΈΡ
ΡΡΠΎΡΠΎΠ½Π½ΠΈΠΊΠΎΠ².
Π Π°ΡΡΠΌΠ°ΡΡΠΈΠ²Π°Π΅ΡΡΡ ΠΎΡΠ½ΠΎΡΠ΅Π½ΠΈΠ΅ Π°ΠΌΠ΅ΡΠΈΠΊΠ°Π½ΡΠΊΠΎΠ³ΠΎ ΠΎΠ±ΡΠ΅ΡΡΠ²Π° ΠΊ ΠΊΠ°ΡΠ½Π°Π²Π°Π»ΡΠ½ΠΎΠΉ ΠΏΠΎΠ»ΠΈΡΠΈΠΊΠ΅ Π΄Π΅ΠΉΡΡΠ²ΡΡΡΠΈΡ
ΠΏΠΎΠ»ΠΈΡΠΈΠΊΠΎΠ² Π‘Π¨Π. ΠΡΠΎΠ²ΠΎΠ΄ΠΈΡΡΡ ΡΠΎΠΏΠΎΡΡΠ°Π²Π»Π΅Π½ΠΈΠ΅ ΠΈΠΌΠΈΠ΄ΠΆΠ°, ΡΠΎΠ·Π΄Π°Π²Π°Π΅ΠΌΠΎΠ³ΠΎ ΡΠ»ΠΈΡΠ°ΡΠ½ΠΎΠΉ ΡΠ°ΡΡΠΈ ΠΠΌΠ΅ΡΠΈΠΊΠΈ ΠΈ ΠΌΠ½Π΅Π½ΠΈΠ΅ΠΌ ΡΠΊΡΠΏΠ΅ΡΡΠΎΠ², Π°Π½Π°Π»ΠΈΠ·ΠΈΡΡΡΡΠΈΡ
ΠΈ Π΄Π°ΡΡΠΈΡ
ΠΊΡΠΈΡΠΈΡΠ΅ΡΠΊΡΡ ΠΎΡΠ΅Π½ΠΊΡ ΡΠ΅Π°Π»ΡΠ½ΡΠΌ Π²ΡΡΡΡΠΏΠ»Π΅Π½ΠΈΡΠΌ ΠΈ Π΄Π΅ΠΉΡΡΠ²ΠΈΡΠΌ ΠΏΠΎΠ»ΠΈΡΠΈΠΊΠΎΠ². Π’Π°ΠΊΠΆΠ΅, ΠΎΡΡΠ»Π΅ΠΆΠΈΠ²Π°Π΅ΡΡΡ Ρ
ΡΠΎΠ½ΠΎΠ»ΠΎΠ³ΠΈΡΠ΅ΡΠΊΠΎΠ΅ ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΠ΅ ΠΌΠ½Π΅Π½ΠΈΠΉ ΡΡΠ΅Π΄ΠΈ Π°ΠΌΠ΅ΡΠΈΠΊΠ°Π½ΡΠΊΠΎΠΉ ΡΠ»ΠΈΡΡ.
ΠΠ»Ρ Π±ΠΎΠ»Π΅Π΅ ΡΠΎΡΠ½ΠΎΠ³ΠΎ Π°Π½Π°Π»ΠΈΠ·Π° ΠΊΠ°ΡΠ½Π°Π²Π°Π»ΡΠ½ΠΎΠΉ ΠΏΠΎΠ»ΠΈΡΠΈΠΊΠΈ Π°ΠΌΠ΅ΡΠΈΠΊΠ°Π½ΡΠΊΠΎΠΉ ΡΠ»ΠΈΡΡ, Π±ΡΠ»ΠΈ ΡΠ°ΡΡΠΌΠΎΡΡΠ΅Π½Ρ Π½Π΅ ΡΠΎΠ»ΡΠΊΠΎ Π½Π΅Π΄Π°Π²Π½ΠΈΠ΅ Π²ΡΡΠΊΠ°Π·ΡΠ²Π°Π½ΠΈΡ Π΄Π΅ΠΉΡΡΠ²ΡΡΡΠΈΡ
ΠΏΠΎΠ»ΠΈΡΠΈΠΊΠΎΠ² Π‘ΠΎΠ΅Π΄ΠΈΠ½ΡΠ½Π½ΡΡ
Π¨ΡΠ°ΡΠΎΠ² Π² ΡΠ΅ΠΊΡΡΠ΅ΠΌ 2022 Π³ΠΎΠ΄Ρ, Π½ΠΎ ΠΈ Π½Π΅ΠΊΠΎΡΠΎΡΡΠ΅ ΠΊΠ»ΡΡΠ΅Π²ΡΠ΅ Π²ΡΡΠΊΠ°Π·ΡΠ²Π°Π½ΠΈΡ Π² ΠΊΠΎΠ½ΡΠ΅ΠΊΡΡΠ΅ ΡΠ΅ΠΌΡ ΡΡΠ°ΡΡΠΈ, Π½Π°ΡΠΈΠ½Π°Ρ Ρ 2015 Π³ΠΎΠ΄Π°.
ΠΠ° ΠΎΡΠ½ΠΎΠ²Π΅ ΠΏΡΠΈΠ²Π΅Π΄ΡΠ½Π½ΡΡ
ΠΏΡΠΈΠΌΠ΅ΡΠΎΠ², Π΄ΠΎΠΊΠ°Π·ΡΠ²Π°Π΅ΡΡΡ ΠΊΠ°ΡΠ½Π°Π²Π°Π»ΡΠ½ΡΠΉ Ρ
Π°ΡΠ°ΠΊΡΠ΅Ρ ΡΠΎΠ²ΡΠ΅ΠΌΠ΅Π½Π½ΡΡ
Π°ΠΌΠ΅ΡΠΈΠΊΠ°Π½ΡΠΊΠΈΡ
ΠΏΠΎΠ»ΠΈΡΠΈΠΊΠΎΠ², ΡΠ°ΡΡ
ΠΎΠΆΠ΄Π΅Π½ΠΈΠ΅ ΡΠ»ΠΎΠ² ΠΈ Π΄Π΅ΠΉΡΡΠ²ΠΈΠΉ Π±ΡΠ²ΡΠ΅Π³ΠΎ ΠΈ Π½ΡΠ½Π΅ΡΠ½Π΅Π³ΠΎ Π»ΠΈΠ΄Π΅ΡΠΎΠ² Π‘ΠΎΠ΅Π΄ΠΈΠ½ΡΠ½Π½ΡΡ
Π¨ΡΠ°ΡΠΎΠ² ΠΈ ΠΈΡ
Π°Π΄ΠΌΠΈΠ½ΠΈΡΡΡΠ°ΡΠΈΠΉ. ΠΡΠΈΠ²ΠΎΠ΄ΡΡΡΡ ΠΏΠΎΠ΄ΡΠΎΠ±Π½ΡΠ΅ Π°Π½Π°Π»ΠΈΠ·Ρ ΠΊΠ»ΡΡΠ΅Π²ΡΡ
Π°ΠΌΠ΅ΡΠΈΠΊΠ°Π½ΡΠΊΠΈΡ
ΠΏΠΎΠ»ΠΈΡΠΎΠ»ΠΎΠ³ΠΎΠ² ΠΈ ΠΆΡΡΠ½Π°Π»ΠΈΡΡΠΎΠ² Π² ΠΊΠΎΠ½ΡΠ΅ΠΊΡΡΠ΅ Π½Π΅ΡΠ΅ΡΡΡΠ·Π½ΠΎΡΡΠΈ Π°Π΄ΠΌΠΈΠ½ΠΈΡΡΡΠ°ΡΠΈΠΈ Π‘Π¨Π. ΠΠ½Π°Π»ΠΈΠ·ΠΈΡΡΠ΅ΡΡΡ ΡΠ²ΡΠ·Ρ ΡΠ΅ΠΎΡΠΈΠΈ Β«Π³Π»ΡΠ±ΠΈΠ½Π½ΠΎΠ³ΠΎ Π³ΠΎΡΡΠ΄Π°ΡΡΡΠ²Π°Β» Ρ ΠΏΠΎΠ»ΠΈΡΠΈΠΊΠΎΠΉ ΠΠΎΠ½Π°Π»ΡΠ΄Π° Π’ΡΠ°ΠΌΠΏΠ°. ΠΡΠ΄Π΅Π»ΡΠ΅ΡΡΡ Π·Π°ΠΊΠΎΠ½ΠΎΠΌΠ΅ΡΠ½ΠΎΡΡΡ ΠΏΠΎΡΠ²Π»Π΅Π½ΠΈΡ ΡΡΡΠΎΡΠΎΠ±ΠΎΠ² Π² Π°Π΄ΠΌΠΈΠ½ΠΈΡΡΡΠ°ΡΠΈΠΈ ΠΠ°ΠΉΠ΄Π΅Π½Π°
ΠΠ‘Π‘ΠΠΠΠΠΠΠΠΠ ΠΠΠΠ―ΠΠΠ― Π‘Π’Π Π£ΠΠ’Π£Π ΠΠΠΠ Π‘ΠΠ‘Π’ΠΠ―ΠΠΠ― Π ΠΠ‘ΠΠΠΠΠ ΠΠ ΠΠ ΠΠ‘Π’ΠΠΠΠΠ§ΠΠ‘ΠΠΠ Π‘Π’Π ΠΠΠΠΠ Π ΠΠΠ₯ΠΠΠΠ§ΠΠ‘ΠΠΠ Π‘ΠΠΠΠ‘Π’ΠΠ Π€ΠΠ Π‘ΠΠΠΠΠ AL-50 ΠΠΠ‘.%SN ΠΠΠ’ΠΠΠΠ ΠΠΠΠΠΠΠΠΠΠ’ΠΠ ΠΠΠΠΠΠ―
Nanoindentation is used to measure Young's modulus, the hardness, the plasticity, and the yield strength of the phases in Al-50 wt % Sn alloy samples prepared by a traditional method and using liquid-state homogenization. The effect of an increase in the cooling rate by an order of magnitude and alloying with 0.06 wt % Ti or 1 wt % Zr on the mechanical properties of the phases in the Al-50 wt % Sn alloy is studied. The most substantial effect on Young's modulus of the phases in the Al-50 wt % Sn alloy is found to be exerted by the homogenization of the metallic liquid and the introduction of zirconium in the alloy melt: the metal forming of an ingot is improved substantially. Β© 2013 Pleiades Publishing, Ltd
Assessment of the Use of the Potential of Agricultural Lands in Voronezh Region
The uniqueness and specifics of the land significantly affects both the organization of agricultural production and the rural area management. In order to make well-founded management decisions the economic subjects and public authorities need scientific grounding for assessment of land potential and its use efficiency. The authors suggest using three approaches to land quality and use assessment: agro-climatic potential, land quality score and agricultural production per hectare. Uniting these approaches into single assessment procedure produces a fairly objectively estimation of the economic potential of agricultural land in each selected territory
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