209 research outputs found
The influence of multilayer metal-carbon coatings composition with different arrangement of functional layers on their surface morphology
This research was supported by the grants of Belarussian Republican Foundation for Fundamental Research BRFFR β T17KIG-009
Friction coefficient obtained using AFM as a criterion of changes in the surface properties after low-temperature plasma treatment
This research was supported by the grant of Belarussian Republican Foundation for Fundamental Research BRFFR No.F17-118
The influence silicon dioxide nanoparticles on mechanical properties of erythrocyte and platelet membranes estimated by atomic force microscopy method
The investigation performed within the Programs of State Research βEnergy systems, process and technologiesβ, project 2.2
Absolute quantum yield measurements of fluorescent proteins using a plasmonic nanocavity
One of the key photophysical properties of fluorescent proteins that is most difficult to measure is the quantum yield. It describes how efficiently a fluorophore converts absorbed light into fluorescence. Its measurement using conventional methods become particularly problematic when it is unknown how many of the proposedly fluorescent molecules of a sample are indeed fluorescent (for example due to incomplete maturation, or the presence of photophysical dark states). Here, we use a plasmonic nanocavity-based method to measure absolute quantum yield values of commonly used fluorescent proteins. The method is calibration-free, does not require knowledge about maturation or potential dark states, and works on minute amounts of sample. The insensitivity of the nanocavity-based method to the presence of non-luminescent species allowed us to measure precisely the quantum yield of photo-switchable proteins in their on-state and to analyze the origin of the residual fluorescence of protein ensembles switched to the dark state
Π£ΡΠΎΠ²Π΅ΡΡΠ΅Π½ΡΡΠ²ΠΎΠ²Π°Π½Π½Π°Ρ ΠΌΠΎΠ΄Π΅Π»Ρ ΠΏΡΠ΅ΡΡΠΎΠ²Π°Π½ΠΈΡ ΠΏΠΎΡΠΎΡΠΊΠΎΠ²ΠΎΠΉ ΡΠΌΠ΅ΡΠΈ Π² Π²Π°Π»ΠΊΠΎΠ²ΠΎΠΌ ΠΏΡΠ΅ΡΡΠ΅
A new mathematical model of mineral fertilizer compacting using a roll compactor is developed. This model is based on the transition to the values of stress tensor components averaged over the cross-sectional area of the powder mixture ο¬ow. To deο¬ne these stresses, equations of equilibrium of the elementary layer determined in the mixture by two planes perpendicular to the ο¬ow direction are composed. To obtain relatively simple analytical relations in the calculations, the hypothesis of a power-law dependence of hydrostatic pressure on mixture density, accepted in the framework of the Johansen model, was used. In order to take into account changes in the mechanical characteristics of the mixture (angle of internal friction, coefο¬cient of external friction, transverse strain coefο¬cient) while compacting, we approximated the known experimental dependencies of the corresponding characteristics on the density. The inter-particle cohesion parameter was taken to be proportional to the hydrostatic pressure. The model allows calculating the gap between the rolls surfaces for a given initial bulk density and the required ο¬ake density. With the known gap value, the distribution of the axial average stresses in the powder mixture, the normal and shear stresses on the rollsβ surfaces are determined. The results of the calculations of the rolls surface gap and the normal roll pressure diagram are compared with the experimental data given in the literature for the urea compacting process.Π Π°Π·ΡΠ°Π±ΠΎΡΠ°Π½Π° ΠΌΠ°ΡΠ΅ΠΌΠ°ΡΠΈΡΠ΅ΡΠΊΠ°Ρ ΠΌΠΎΠ΄Π΅Π»Ρ ΠΏΡΠ΅ΡΡΠΎΠ²Π°Π½ΠΈΡ ΠΌΠΈΠ½Π΅ΡΠ°Π»ΡΠ½ΠΎΠ³ΠΎ ΡΠ΄ΠΎΠ±ΡΠ΅Π½ΠΈΡ Π½Π° Π²Π°Π»ΠΊΠΎΠ²ΠΎΠΌ ΠΏΡΠ΅ΡΡΠ΅. ΠΠ°Π½Π½Π°Ρ ΠΌΠΎΠ΄Π΅Π»Ρ ΠΎΡΠ½ΠΎΠ²Π°Π½Π° Π½Π° ΠΏΠ΅ΡΠ΅Ρ
ΠΎΠ΄Π΅ ΠΊ ΡΡΡΠ΅Π΄Π½Π΅Π½Π½ΡΠΌ ΠΏΠΎ ΠΏΠ»ΠΎΡΠ°Π΄ΠΈ ΠΏΠΎΠΏΠ΅ΡΠ΅ΡΠ½ΠΎΠ³ΠΎ ΡΠ΅ΡΠ΅Π½ΠΈΡ ΠΏΠΎΡΠΎΠΊΠ° ΠΏΠΎΡΠΎΡΠΊΠΎΠ²ΠΎΠΉ ΡΠΌΠ΅ΡΠΈ Π·Π½Π°ΡΠ΅Π½ΠΈΡΠΌ ΠΊΠΎΠΌΠΏΠΎΠ½Π΅Π½Ρ ΡΠ΅Π½Π·ΠΎΡΠ° Π½Π°ΠΏΡΡΠΆΠ΅Π½ΠΈΠΉ. ΠΠ»Ρ ΠΎΠΏΡΠ΅Π΄Π΅Π»Π΅Π½ΠΈΡ ΡΡΠΈΡ
Π½Π°ΠΏΡΡΠΆΠ΅Π½ΠΈΠΉ ΡΠΎΡΡΠ°Π²Π»ΡΡΡΡΡ ΡΡΠ°Π²Π½Π΅Π½ΠΈΡ ΡΠ°Π²Π½ΠΎΠ²Π΅ΡΠΈΡ ΡΠ»Π΅ΠΌΠ΅Π½ΡΠ°ΡΠ½ΠΎΠ³ΠΎ ΡΠ»ΠΎΡ, Π²ΡΠ΄Π΅Π»ΡΠ΅ΠΌΠΎΠ³ΠΎ Π² ΡΠΌΠ΅ΡΠΈ Π΄Π²ΡΠΌΡ ΠΏΠ»ΠΎΡΠΊΠΎΡΡΡΠΌΠΈ, ΠΏΠ΅ΡΠΏΠ΅Π½Π΄ΠΈΠΊΡΠ»ΡΡΠ½ΡΠΌΠΈ ΠΊ Π½Π°ΠΏΡΠ°Π²Π»Π΅Π½ΠΈΡ ΠΏΠΎΡΠΎΠΊΠ°. ΠΠ»Ρ ΠΎΠ±Π΅ΡΠΏΠ΅ΡΠ΅Π½ΠΈΡ Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎΡΡΠΈ ΠΏΠΎΠ»ΡΡΠ΅Π½ΠΈΡ ΠΎΡΠ½ΠΎΡΠΈΡΠ΅Π»ΡΠ½ΠΎ ΠΏΡΠΎΡΡΡΡ
Π°Π½Π°Π»ΠΈΡΠΈΡΠ΅ΡΠΊΠΈΡ
ΡΠΎΠΎΡΠ½ΠΎΡΠ΅Π½ΠΈΠΉ ΠΏΡΠΈ ΡΠ°ΡΡΠ΅ΡΠ°Ρ
ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½Π° ΠΏΡΠΈΠ½ΡΡΠ°Ρ Π² ΡΠ°ΠΌΠΊΠ°Ρ
ΠΌΠΎΠ΄Π΅Π»ΠΈ ΠΠΎΡ
Π°Π½ΡΠ΅Π½Π° Π³ΠΈΠΏΠΎΡΠ΅Π·Π° ΠΎ ΡΡΠ΅ΠΏΠ΅Π½Π½ΠΎΠΉ Π·Π°Π²ΠΈΡΠΈΠΌΠΎΡΡΠΈ Π³ΠΈΠ΄ΡΠΎΡΡΠ°ΡΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ Π΄Π°Π²Π»Π΅Π½ΠΈΡ ΠΎΡ ΠΏΠ»ΠΎΡΠ½ΠΎΡΡΠΈ ΡΠΌΠ΅ΡΠΈ. ΠΠ»Ρ ΡΡΠ΅ΡΠ° ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΡ ΠΌΠ΅Ρ
Π°Π½ΠΈΡΠ΅ΡΠΊΠΈΡ
Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊ ΡΠΌΠ΅ΡΠΈ (ΡΠ³Π»Π° Π²Π½ΡΡΡΠ΅Π½Π½Π΅Π³ΠΎ ΡΡΠ΅Π½ΠΈΡ, ΠΊΠΎΡΡΡΠΈΡΠΈΠ΅Π½ΡΠ° Π²Π½Π΅ΡΠ½Π΅Π³ΠΎ ΡΡΠ΅Π½ΠΈΡ, ΠΊΠΎΡΡΡΠΈΡΠΈΠ΅Π½ΡΠ° ΠΏΠΎΠΏΠ΅ΡΠ΅ΡΠ½ΠΎΠΉ Π΄Π΅ΡΠΎΡΠΌΠ°ΡΠΈΠΈ) Π² ΠΏΡΠΎΡΠ΅ΡΡΠ΅ ΠΏΡΠ΅ΡΡΠΎΠ²Π°Π½ΠΈΡ ΠΏΡΠΎΠΈΠ·Π²ΠΎΠ΄ΠΈΠ»Π°ΡΡ Π°ΠΏΠΏΡΠΎΠΊΡΠΈΠΌΠ°ΡΠΈΡ ΠΈΠ·Π²Π΅ΡΡΠ½ΡΡ
ΡΠΊΡΠΏΠ΅ΡΠΈΠΌΠ΅Π½ΡΠ°Π»ΡΠ½ΡΡ
Π·Π°Π²ΠΈΡΠΈΠΌΠΎΡΡΠ΅ΠΉ ΡΠΎΠΎΡΠ²Π΅ΡΡΡΠ²ΡΡΡΠΈΡ
Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊ ΠΎΡ ΠΏΠ»ΠΎΡΠ½ΠΎΡΡΠΈ. ΠΠ°ΡΠ°ΠΌΠ΅ΡΡ ΠΌΠ΅ΠΆΡΠ°ΡΡΠΈΡΠ½ΠΎΠ³ΠΎ ΡΡΠ΅ΠΏΠ»Π΅Π½ΠΈΡ ΠΏΡΠΈΠ½ΠΈΠΌΠ°Π»ΡΡ ΠΏΡΠΎΠΏΠΎΡΡΠΈΠΎΠ½Π°Π»ΡΠ½ΡΠΌ Π³ΠΈΠ΄ΡΠΎΡΡΠ°ΡΠΈΡΠ΅ΡΠΊΠΎΠΌΡ Π΄Π°Π²Π»Π΅Π½ΠΈΡ. ΠΠΎΠ΄Π΅Π»Ρ ΠΏΠΎΠ·Π²ΠΎΠ»ΡΠ΅Ρ Π²ΡΡΠΈΡΠ»ΠΈΡΡ Π·Π½Π°ΡΠ΅Π½ΠΈΠ΅ Π·Π°Π·ΠΎΡΠ° ΠΌΠ΅ΠΆΠ΄Ρ ΠΏΠΎΠ²Π΅ΡΡ
Π½ΠΎΡΡΡΠΌΠΈ Π²Π°Π»ΠΎΠ² ΠΏΡΠΈ Π·Π°Π΄Π°Π½Π½ΡΡ
Π·Π½Π°ΡΠ΅Π½ΠΈΡΡ
ΠΈΡΡ
ΠΎΠ΄Π½ΠΎΠΉ Π½Π°ΡΡΠΏΠ½ΠΎΠΉ ΠΏΠ»ΠΎΡΠ½ΠΎΡΡΠΈ ΡΠΌΠ΅ΡΠΈ ΠΈ ΡΡΠ΅Π±ΡΠ΅ΠΌΠΎΠΉ ΠΏΠ»ΠΎΡΠ½ΠΎΡΡΠΈ ΠΏΠ»ΠΈΡΠΊΠΈ. ΠΡΠΈ ΠΈΠ·Π²Π΅ΡΡΠ½ΠΎΠΌ Π·Π½Π°ΡΠ΅Π½ΠΈΠΈ Π·Π°Π·ΠΎΡΠ° ΡΡΡΠ°Π½Π°Π²Π»ΠΈΠ²Π°ΡΡΡΡ ΡΠ°ΡΠΏΡΠ΅Π΄Π΅Π»Π΅Π½ΠΈΡ ΠΎΡΠ΅Π²ΡΡ
ΡΡΡΠ΅Π΄Π½Π΅Π½Π½ΡΡ
Π½Π°ΠΏΡΡΠΆΠ΅Π½ΠΈΠΉ Π² ΠΏΠΎΡΠΎΡΠΊΠΎΠ²ΠΎΠΉ ΡΠΌΠ΅ΡΠΈ, Π½ΠΎΡΠΌΠ°Π»ΡΠ½ΠΎΠ³ΠΎ ΠΈ ΡΠ΄Π²ΠΈΠ³ΠΎΠ²ΠΎΠ³ΠΎ Π½Π°ΠΏΡΡΠΆΠ΅Π½ΠΈΠΉ Π½Π° ΠΏΠΎΠ²Π΅ΡΡ
Π½ΠΎΡΡΠΈ Π²Π°Π»ΠΎΠ². Π Π΅Π·ΡΠ»ΡΡΠ°ΡΡ ΡΠ°ΡΡΠ΅ΡΠΎΠ² Π·Π°Π·ΠΎΡΠ° ΠΌΠ΅ΠΆΠ΄Ρ ΠΏΠΎΠ²Π΅ΡΡ
Π½ΠΎΡΡΡΠΌΠΈ Π²Π°Π»ΠΎΠ² ΠΈ ΡΠΏΡΡΡ Π½ΠΎΡΠΌΠ°Π»ΡΠ½ΠΎΠ³ΠΎ Π΄Π°Π²Π»Π΅Π½ΠΈΡ Π½Π° Π²Π°Π» ΡΠΎΠΏΠΎΡΡΠ°Π²Π»Π΅Π½Ρ Ρ ΠΏΡΠΈΠ²Π΅Π΄Π΅Π½Π½ΡΠΌΠΈ Π² Π»ΠΈΡΠ΅ΡΠ°ΡΡΡΠ½ΡΡ
ΠΈΡΡΠΎΡΠ½ΠΈΠΊΠ°Ρ
ΡΠΊΡΠΏΠ΅ΡΠΈΠΌΠ΅Π½ΡΠ°Π»ΡΠ½ΡΠΌΠΈ Π΄Π°Π½Π½ΡΠΌΠΈ Π΄Π»Ρ ΠΏΡΠΎΡΠ΅ΡΡΠ° ΠΏΡΠ΅ΡΡΠΎΠ²Π°Π½ΠΈΡ ΠΌΠΎΡΠ΅Π²ΠΈΠ½Ρ
ΠΠΎΠ΄Π΅Π»ΠΈΡΠΎΠ²Π°Π½ΠΈΠ΅ ΡΠ°Π΄ΠΈΠ°Π»ΡΠ½ΡΡ ΠΊΠΎΠ»Π΅Π±Π°Π½ΠΈΠΉ ΠΏΠΎΠ΄ΠΏΡΡΠΆΠΈΠ½Π΅Π½Π½ΠΎΠ³ΠΎ Π²Π°Π»ΠΊΠ° Π²Π°Π»ΡΡ-ΠΏΡΠ΅ΡΡΠ°
Carried out simulation of oscillations of a spring-loaded roll in a roll compactor when interacting the powder being compacted with the rolls. Considering the separation of the feed and compaction areas in the contact area of the roll with the material being compacted, we obtain the dependence of the force acting on the roll on the gap size between the rolls. It is shown that this dependence is non-linear, and it can be described with a sufficiently high accuracy degree by an exponential function with a negative exponent in the working range. The given numerical solution of the equation of free nonlinear oscillations of the spring-loaded roll has shown that considering the deformation of the material being compacted leads to a reduction of the natural frequency of the system by 20β25 % compared to the case, where the pressure force of the powder on the roll is assumed to be independent of the gap size. The nonlinearity of the dependence of the pressure force on the gap also leads to the increase by 10 % in the calculated values of the maximum displacements. The developed approach to the calculation of oscillations of the spring-loaded roll in the roll compactor enables to take into account the peculiarities of deformation of the powder being compacted during its interaction with the rolls. In addition, it allows estimating the frequencies and oscillation amplitudes and setting the optimum range of spring rate values, at which the occurrence of resonance in the machine is not possible.ΠΡΠΏΠΎΠ»Π½Π΅Π½ΠΎ ΠΌΠΎΠ΄Π΅Π»ΠΈΡΠΎΠ²Π°Π½ΠΈΠ΅ ΠΊΠΎΠ»Π΅Π±Π°Π½ΠΈΠΉ ΠΏΠΎΠ΄ΠΏΡΡΠΆΠΈΠ½Π΅Π½Π½ΠΎΠ³ΠΎ Π²Π°Π»ΠΊΠ° Π²Π°Π»ΡΡ-ΠΏΡΠ΅ΡΡΠ° ΠΏΡΠΈ Π²Π·Π°ΠΈΠΌΠΎΠ΄Π΅ΠΉΡΡΠ²ΠΈΠΈ ΠΏΡΠ΅ΡΡΡΠ΅ΠΌΠΎΠ³ΠΎ ΠΏΠΎΡΠΎΡΠΊΠ° Ρ Π²Π°Π»ΠΊΠ°ΠΌΠΈ. Π‘ ΡΡΠ΅ΡΠΎΠΌ Π²ΡΠ΄Π΅Π»Π΅Π½ΠΈΡ Π² ΠΎΠ±Π»Π°ΡΡΠΈ ΠΊΠΎΠ½ΡΠ°ΠΊΡΠ° Π²Π°Π»ΠΊΠ° Ρ ΠΏΡΠ΅ΡΡΡΠ΅ΠΌΡΠΌ ΠΌΠ°ΡΠ΅ΡΠΈΠ°Π»ΠΎΠΌ Π·ΠΎΠ½ ΠΏΠΎΠ΄Π°ΡΠΈ ΠΈ ΠΏΡΠ΅ΡΡΠΎΠ²Π°Π½ΠΈΡ, ΠΏΠΎΠ»ΡΡΠ΅Π½Π° Π·Π°Π²ΠΈΡΠΈΠΌΠΎΡΡΡ ΡΠΈΠ»Ρ, Π΄Π΅ΠΉΡΡΠ²ΡΡΡΠ΅ΠΉ Π½Π° Π²Π°Π»ΠΎΠΊ, ΠΎΡ Π²Π΅Π»ΠΈΡΠΈΠ½Ρ Π·Π°Π·ΠΎΡΠ° ΠΌΠ΅ΠΆΠ΄Ρ Π²Π°Π»ΠΊΠ°ΠΌΠΈ. ΠΠΎΠΊΠ°Π·Π°Π½ΠΎ, ΡΡΠΎ ΡΡΠ° Π·Π°Π²ΠΈΡΠΈΠΌΠΎΡΡΡ ΠΈΠΌΠ΅Π΅Ρ Π½Π΅Π»ΠΈΠ½Π΅ΠΉΠ½ΡΠΉ Ρ
Π°ΡΠ°ΠΊΡΠ΅Ρ, ΠΏΡΠΈΡΠ΅ΠΌ Π² ΡΠ°Π±ΠΎΡΠ΅ΠΌ Π΄ΠΈΠ°ΠΏΠ°Π·ΠΎΠ½Π΅ Ρ Π΄ΠΎΡΡΠ°ΡΠΎΡΠ½ΠΎ Π²ΡΡΠΎΠΊΠΎΠΉ ΡΡΠ΅ΠΏΠ΅Π½ΡΡ ΡΠΎΡΠ½ΠΎΡΡΠΈ ΠΌΠΎΠΆΠ΅Ρ Π±ΡΡΡ ΠΎΠΏΠΈΡΠ°Π½Π° ΡΡΠ΅ΠΏΠ΅Π½Π½ΠΎΠΉ ΡΡΠ½ΠΊΡΠΈΠ΅ΠΉ Ρ ΠΎΡΡΠΈΡΠ°ΡΠ΅Π»ΡΠ½ΡΠΌ ΠΏΠΎΠΊΠ°Π·Π°ΡΠ΅Π»Π΅ΠΌ ΡΡΠ΅ΠΏΠ΅Π½ΠΈ. ΠΡΠΈΠ²Π΅Π΄Π΅Π½ΠΎ ΡΠΈΡΠ»Π΅Π½Π½ΠΎΠ΅ ΡΠ΅ΡΠ΅Π½ΠΈΠ΅ ΡΡΠ°Π²Π½Π΅Π½ΠΈΡ ΡΠ²ΠΎΠ±ΠΎΠ΄Π½ΡΡ
Π½Π΅Π»ΠΈΠ½Π΅ΠΉΠ½ΡΡ
ΠΊΠΎΠ»Π΅Π±Π°Π½ΠΈΠΉ ΠΏΠΎΠ΄ΠΏΡΡΠΆΠΈΠ½Π΅Π½Π½ΠΎΠ³ΠΎ Π²Π°Π»ΠΊΠ°, ΠΊΠΎΡΠΎΡΠΎΠ΅ ΠΏΡΠΎΠ΄Π΅ΠΌΠΎΠ½ΡΡΡΠΈΡΠΎΠ²Π°Π»ΠΎ, ΡΡΠΎ ΡΡΠ΅Ρ Π΄Π΅ΡΠΎΡΠΌΠΈΡΠΎΠ²Π°Π½ΠΈΡ ΡΠΆΠΈΠΌΠ°Π΅ΠΌΠΎΠ³ΠΎ ΠΌΠ°ΡΠ΅ΡΠΈΠ°Π»Π° ΠΏΡΠΈΠ²ΠΎΠ΄ΠΈΡ ΠΊ ΡΠ½ΠΈΠΆΠ΅Π½ΠΈΡ ΡΠ°ΡΡΠΎΡ ΡΠΎΠ±ΡΡΠ²Π΅Π½Π½ΡΡ
ΠΊΠΎΠ»Π΅Π±Π°Π½ΠΈΠΉ ΡΠΈΡΡΠ΅ΠΌΡ Π½Π° 20β25 % ΠΏΠΎ ΡΡΠ°Π²Π½Π΅Π½ΠΈΡ ΡΠΎ ΡΠ»ΡΡΠ°Π΅ΠΌ, ΠΏΡΠΈ ΠΊΠΎΡΠΎΡΠΎΠΌ ΡΠΈΠ»Π° Π΄Π°Π²Π»Π΅Π½ΠΈΡ ΠΏΠΎΡΠΎΡΠΊΠ° Π½Π° Π²Π°Π»ΠΎΠΊ ΠΏΡΠΈΠ½ΠΈΠΌΠ°Π΅ΡΡΡ Π½Π΅ Π·Π°Π²ΠΈΡΡΡΠ΅ΠΉ ΠΎΡ Π²Π΅Π»ΠΈΡΠΈΠ½Ρ Π·Π°Π·ΠΎΡΠ°. ΠΠ΅Π»ΠΈΠ½Π΅ΠΉΠ½ΠΎΡΡΡ Π·Π°Π²ΠΈΡΠΈΠΌΠΎΡΡΠΈ ΡΠΈΠ»Ρ Π΄Π°Π²Π»Π΅Π½ΠΈΡ ΠΎΡ Π·Π°Π·ΠΎΡΠ° ΠΏΡΠΈΠ²ΠΎΠ΄ΠΈΡ ΡΠ°ΠΊΠΆΠ΅ ΠΊ ΡΠ²Π΅Π»ΠΈΡΠ΅Π½ΠΈΡ Π½Π° 10 % ΡΠ°ΡΡΠ΅ΡΠ½ΡΡ
Π·Π½Π°ΡΠ΅Π½ΠΈΠΉ ΠΌΠ°ΠΊΡΠΈΠΌΠ°Π»ΡΠ½ΡΡ
ΡΠΌΠ΅ΡΠ΅Π½ΠΈΠΉ. Π Π°Π·ΡΠ°Π±ΠΎΡΠ°Π½Π½ΡΠΉ ΠΏΠΎΠ΄Ρ
ΠΎΠ΄ ΠΊ ΡΠ°ΡΡΠ΅ΡΡ ΠΊΠΎΠ»Π΅Π±Π°Π½ΠΈΠΉ ΠΏΠΎΠ΄ΡΠ΅ΡΡΠΎΡΠ΅Π½Π½ΠΎΠ³ΠΎ Π²Π°Π»ΠΊΠ° Π²Π°Π»ΡΡ-ΠΏΡΠ΅ΡΡΠ° ΠΏΠΎΠ·Π²ΠΎΠ»ΡΠ΅Ρ ΡΡΠ΅ΡΡΡ ΠΎΡΠΎΠ±Π΅Π½Π½ΠΎΡΡΠΈ Π΄Π΅ΡΠΎΡΠΌΠΈΡΠΎΠ²Π°Π½ΠΈΡ ΠΏΡΠ΅ΡΡΡΠ΅ΠΌΠΎΠ³ΠΎ ΠΏΠΎΡΠΎΡΠΊΠ° ΠΏΡΠΈ Π΅Π³ΠΎ Π²Π·Π°ΠΈΠΌΠΎΠ΄Π΅ΠΉΡΡΠ²ΠΈΠΈ Ρ Π²Π°Π»ΠΊΠ°ΠΌΠΈ, Π° ΡΠ°ΠΊΠΆΠ΅ ΠΏΠΎΠ·Π²ΠΎΠ»ΡΠ΅Ρ, Π½Π°ΡΡΠ΄Ρ Ρ ΠΎΡΠ΅Π½ΠΊΠΎΠΉ ΡΠ°ΡΡΠΎΡ ΠΈ Π°ΠΌΠΏΠ»ΠΈΡΡΠ΄ ΠΊΠΎΠ»Π΅Π±Π°Π½ΠΈΠΉ, ΡΡΡΠ°Π½ΠΎΠ²ΠΈΡΡ ΠΎΠΏΡΠΈΠΌΠ°Π»ΡΠ½ΡΠΉ Π΄ΠΈΠ°ΠΏΠ°Π·ΠΎΠ½ Π·Π½Π°ΡΠ΅Π½ΠΈΠΉ ΠΊΠΎΡΡΡΠΈΡΠΈΠ΅Π½ΡΠ° ΠΆΠ΅ΡΡΠΊΠΎΡΡΠΈ ΠΏΡΡΠΆΠΈΠ½Ρ, ΠΏΡΠΈ ΠΊΠΎΡΠΎΡΠΎΠΌ ΠΏΠΎΡΠ²Π»Π΅Π½ΠΈΠ΅ ΡΠ΅Π·ΠΎΠ½Π°Π½ΡΠ° Π² ΠΌΠ°ΡΠΈΠ½Π΅ Π±ΡΠ΄Π΅Ρ Π½Π΅Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎ
Π‘ΠΏΠΎΡΠΎΠ±Ρ ΠΏΠΎΠ²ΡΡΠ΅Π½ΠΈΡ ΡΠΎΡΠ½ΠΎΡΡΠΈ ΠΎΠΏΡΠ΅Π΄Π΅Π»Π΅Π½ΠΈΡ Π²ΡΠ·ΠΊΠΎΡΡΠΈ ΡΠ°Π·ΡΡΡΠ΅Π½ΠΈΡ ΡΠ²ΡΡΠ΄ΡΡ Ρ ΡΡΠΏΠΊΠΈΡ ΠΌΠ°ΡΠ΅ΡΠΈΠ°Π»ΠΎΠ² ΠΏΡΠΈ ΠΈΠ½Π΄Π΅Π½ΡΠΈΡΠΎΠ²Π°Π½ΠΈΠΈ
Method for determining of the fracture toughness of brittle materials by indentation is described. The critical stress intensity factor KICΒ quantifies the fracture toughness. Methods were developed and applied to improve the accuracy of KIC determination due to atomic force microscopy and nanoindentation. It is necessary to accurately determine parameters and dimensions of the indentations and cracks formed around them in order to determine the KICβ. Instead of classical optical and scanning electron microscopy an alternative high-resolution method of atomic force microscopy was proposed as an imaging method.Three methods of visualization were compared. Two types of crack opening were considered: along the width without vertical displacement of the material and along the height without opening along the width. Due to lack of contact with the surface of the samples under study, the methods of optical and scanning electron microscopy do not detect cracks with a height opening of less than 100 nm (for optical) and less than 40β50 nm (for scanning electron microscopy). Cracks with opening in width are determined within their resolution. Optical and scanning electron microscopy cannot provide accurate visualization of the deformation area and emerging cracks when applying small loads (less than 1.0 N). The use of atomic force microscopy leads to an increase in accuracy of determining of the length of the indent diagonal up to 9.0 % and of determining of the crack length up to 100 % compared to optical microscopy and up to 67 % compared to scanning electron microscopy. The method of atomic force microscopy due to spatial three-dimensional visualization and high accuracy (XY Β±β0.2 nm, Z Β±β0.03 nm) expands the possibilities of using indentation with low loads.A method was proposed for accuracy increasing of KIC determination by measuring of microhardness from a nanoindenter. It was established that nanoindentation leads to an increase in the accuracy of KIC determination by 16β23 % and eliminates the formation of microcracks in the indentation.ΠΡΠΈΠ²Π΅Π΄Π΅Π½ΠΎ ΠΎΠΏΠΈΡΠ°Π½ΠΈΠ΅ ΠΌΠ΅ΡΠΎΠ΄Π° ΠΎΠΏΡΠ΅Π΄Π΅Π»Π΅Π½ΠΈΡ Π²ΡΠ·ΠΊΠΎΡΡΠΈ ΡΠ°Π·ΡΡΡΠ΅Π½ΠΈΡ Ρ
ΡΡΠΏΠΊΠΈΡ
ΠΌΠ°ΡΠ΅ΡΠΈΠ°Π»ΠΎΠ² ΠΈΠ½Π΄Π΅Π½ΡΠΈΡΠΎΠ²Π°Π½ΠΈΠ΅ΠΌ. ΠΠΎΠ»ΠΈΡΠ΅ΡΡΠ²Π΅Π½Π½ΠΎ Π²ΡΠ·ΠΊΠΎΡΡΡ ΡΠ°Π·ΡΡΡΠ΅Π½ΠΈΡ Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΠ·ΡΠ΅ΡΡΡ ΠΊΡΠΈΡΠΈΡΠ΅ΡΠΊΠΈΠΌ ΠΊΠΎΡΡΡΠΈΡΠΈΠ΅Π½ΡΠΎΠΌ ΠΈΠ½ΡΠ΅Π½ΡΠΈΠ²Π½ΠΎΡΡΠΈ ΡΠ°Π·ΡΡΡΠ΅Π½ΠΈΡ KICβ. ΠΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΠ΅ Π°ΡΠΎΠΌΠ½ΠΎ-ΡΠΈΠ»ΠΎΠ²ΠΎΠΉ ΠΌΠΈΠΊΡΠΎΡΠΊΠΎΠΏΠΈΠΈ ΠΈ Π½Π°Π½ΠΎΠΈΠ½Π΄Π΅Π½ΡΠΈΡΠΎΠ²Π°Π½ΠΈΡ ΠΏΠΎΠ·Π²ΠΎΠ»ΠΈΠ»ΠΎ ΡΠ°Π·ΡΠ°Π±ΠΎΡΠ°ΡΡ ΠΈ ΠΏΡΠΈΠΌΠ΅Π½ΠΈΡΡ ΡΠΏΠΎΡΠΎΠ±Ρ ΠΏΠΎΠ²ΡΡΠ΅Π½ΠΈΡ ΡΠΎΡΠ½ΠΎΡΡΠΈ ΠΎΠΏΡΠ΅Π΄Π΅Π»Π΅Π½ΠΈΡ KICβ. ΠΠ»Ρ ΠΎΠΏΡΠ΅Π΄Π΅Π»Π΅Π½ΠΈΡ KICΒ Π½Π΅ΠΎΠ±Ρ
ΠΎΠ΄ΠΈΠΌΠΎ ΡΠΎΡΠ½ΠΎ ΠΎΠΏΡΠ΅Π΄Π΅Π»ΡΡΡ ΠΏΠ°ΡΠ°ΠΌΠ΅ΡΡΡ ΠΈ ΡΠ°Π·ΠΌΠ΅ΡΡ ΠΎΡΠΏΠ΅ΡΠ°ΡΠΊΠΎΠ² ΠΈΠ½Π΄Π΅Π½ΡΠΈΡΠΎΠ²Π°Π½ΠΈΡ ΠΈ ΠΎΠ±ΡΠ°Π·ΠΎΠ²Π°Π½Π½ΡΡ
Π²ΠΎΠΊΡΡΠ³ Π½ΠΈΡ
ΡΡΠ΅ΡΠΈΠ½. Π ΠΊΠ°ΡΠ΅ΡΡΠ²Π΅ ΠΌΠ΅ΡΠΎΠ΄Π° Π²ΠΈΠ·ΡΠ°Π»ΠΈΠ·Π°ΡΠΈΠΈ Π²ΠΌΠ΅ΡΡΠΎ ΠΊΠ»Π°ΡΡΠΈΡΠ΅ΡΠΊΠΈΡ
ΠΎΠΏΡΠΈΡΠ΅ΡΠΊΠΎΠΉ ΠΈ ΡΠΊΠ°Π½ΠΈΡΡΡΡΠ΅ΠΉ ΡΠ»Π΅ΠΊΡΡΠΎΠ½Π½ΠΎΠΉ ΠΌΠΈΠΊΡΠΎΡΠΊΠΎΠΏΠΈΠΉ ΠΏΡΠ΅Π΄Π»ΠΎΠΆΠ΅Π½ Π°Π»ΡΡΠ΅ΡΠ½Π°ΡΠΈΠ²Π½ΡΠΉ Π²ΡΡΠΎΠΊΠΎΡΠ°Π·ΡΠ΅ΡΠ°ΡΡΠΈΠΉ ΠΌΠ΅ΡΠΎΠ΄ Π°ΡΠΎΠΌΠ½ΠΎ-ΡΠΈΠ»ΠΎΠ²ΠΎΠΉ ΠΌΠΈΠΊΡΠΎΡΠΊΠΎΠΏΠΈΠΈ.ΠΡΠΎΠ²Π΅Π΄Π΅Π½ΠΎ ΡΡΠ°Π²Π½Π΅Π½ΠΈΠ΅ ΡΡΡΡ
ΠΌΠ΅ΡΠΎΠ΄ΠΎΠ² Π²ΠΈΠ·ΡΠ°Π»ΠΈΠ·Π°ΡΠΈΠΈ. Π Π°ΡΡΠΌΠΎΡΡΠ΅Π½ΠΎ Π΄Π²Π° ΡΠΈΠΏΠ° ΡΠ°ΡΠΊΡΡΡΠΈΡ ΡΡΠ΅ΡΠΈΠ½: ΠΏΠΎ ΡΠΈΡΠΈΠ½Π΅ Π±Π΅Π· ΡΠΌΠ΅ΡΠ΅Π½ΠΈΡ ΠΌΠ°ΡΠ΅ΡΠΈΠ°Π»Π° ΠΏΠΎ Π²Π΅ΡΡΠΈΠΊΠ°Π»ΠΈ ΠΈ ΠΏΠΎ Π²ΡΡΠΎΡΠ΅ Π±Π΅Π· ΡΠ°ΡΠΊΡΡΡΠΈΡ ΠΏΠΎ ΡΠΈΡΠΈΠ½Π΅. ΠΠ΅ΡΠΎΠ΄Ρ ΠΎΠΏΡΠΈΡΠ΅ΡΠΊΠΎΠΉ ΠΈ ΡΠΊΠ°Π½ΠΈΡΡΡΡΠ΅ΠΉ ΡΠ»Π΅ΠΊΡΡΠΎΠ½Π½ΠΎΠΉ ΠΌΠΈΠΊΡΠΎΡΠΊΠΎΠΏΠΈΠΉ ΠΈΠ·-Π·Π° ΠΎΡΡΡΡΡΡΠ²ΠΈΡ ΠΊΠΎΠ½ΡΠ°ΠΊΡΠ° Ρ ΠΏΠΎΠ²Π΅ΡΡ
Π½ΠΎΡΡΡΡ ΠΈΡΡΠ»Π΅Π΄ΡΠ΅ΠΌΡΡ
ΠΎΠ±ΡΠ°Π·ΡΠΎΠ² Π½Π΅ ΠΎΠΏΡΠ΅Π΄Π΅Π»ΡΡΡ ΡΡΠ΅ΡΠΈΠ½Ρ Ρ ΡΠ°ΡΠΊΡΡΡΠΈΠ΅ΠΌ ΠΏΠΎ Π²ΡΡΠΎΡΠ΅ ΠΌΠ΅Π½Π΅Π΅ 100 Π½ΠΌ (Π΄Π»Ρ ΠΎΠΏΡΠΈΡΠ΅ΡΠΊΠΎΠΉ) ΠΈ ΠΌΠ΅Π½Π΅Π΅ 40β50 Π½ΠΌ (Π΄Π»Ρ ΡΠΊΠ°Π½ΠΈΡΡΡΡΠ΅ΠΉ ΡΠ»Π΅ΠΊΡΡΠΎΠ½Π½ΠΎΠΉ ΠΌΠΈΠΊΡΠΎΡΠΊΠΎΠΏΠΈΠΈ). Π’ΡΠ΅ΡΠΈΠ½Ρ Ρ ΡΠ°ΡΠΊΡΡΡΠΈΠ΅ΠΌ ΠΏΠΎ ΡΠΈΡΠΈΠ½Π΅ ΠΎΠΏΡΠ΅Π΄Π΅Π»ΡΡΡ Π² ΡΠ°ΠΌΠΊΠ°Ρ
ΡΠ²ΠΎΠ΅ΠΉ ΡΠ°Π·ΡΠ΅ΡΠ°ΡΡΠ΅ΠΉ ΡΠΏΠΎΡΠΎΠ±Π½ΠΎΡΡΠΈ. ΠΠΏΡΠΈΡΠ΅ΡΠΊΠ°Ρ ΠΈ ΡΠΊΠ°Π½ΠΈΡΡΡΡΠ°Ρ ΡΠ»Π΅ΠΊΡΡΠΎΠ½Π½Π°Ρ ΠΌΠΈΠΊΡΠΎΡΠΊΠΎΠΏΠΈΠΈ Π½Π΅ ΠΌΠΎΠ³ΡΡ ΠΎΠ±Π΅ΡΠΏΠ΅ΡΠΈΡΡ ΡΠΎΡΠ½ΡΡ Π²ΠΈΠ·ΡΠ°Π»ΠΈΠ·Π°ΡΠΈΡ ΠΎΠ±Π»Π°ΡΡΠΈ Π΄Π΅ΡΠΎΡΠΌΠ°ΡΠΈΠΈ ΠΈ ΡΠΎΡΠΌΠΈΡΡΡΡΠΈΡ
ΡΡ ΡΡΠ΅ΡΠΈΠ½ ΠΏΡΠΈ ΠΏΡΠΈΠΌΠ΅Π½Π΅Π½ΠΈΠΈ ΠΌΠ°Π»ΡΡ
Π½Π°Π³ΡΡΠ·ΠΎΠΊ (ΠΌΠ΅Π½ΡΡΠ΅ 1,0 Π). ΠΡΠΈΠΌΠ΅Π½Π΅Π½ΠΈΠ΅ Π°ΡΠΎΠΌΠ½ΠΎ-ΡΠΈΠ»ΠΎΠ²ΠΎΠΉ ΠΌΠΈΠΊΡΠΎΡΠΊΠΎΠΏΠΈΠΈ ΠΏΡΠΈΠ²ΠΎΠ΄ΠΈΡ ΠΊ ΠΏΠΎΠ²ΡΡΠ΅Π½ΠΈΡ ΡΠΎΡΠ½ΠΎΡΡΠΈ ΠΎΠΏΡΠ΅Π΄Π΅Π»Π΅Π½ΠΈΡ Π΄Π»ΠΈΠ½Ρ Π΄ΠΈΠ°Π³ΠΎΠ½Π°Π»ΠΈ ΠΎΡΠΏΠ΅ΡΠ°ΡΠΊΠ° Π΄ΠΎ 9,0 % ΠΈ ΠΎΠΏΡΠ΅Π΄Π΅Π»Π΅Π½ΠΈΡ Π΄Π»ΠΈΠ½Ρ ΡΡΠ΅ΡΠΈΠ½Ρ Π΄ΠΎ 100 % ΠΏΠΎ ΡΡΠ°Π²Π½Π΅Π½ΠΈΡ Ρ ΠΎΠΏΡΠΈΡΠ΅ΡΠΊΠΎΠΉ ΠΌΠΈΠΊΡΠΎΡΠΊΠΎΠΏΠΈΠ΅ΠΉ ΠΈ Π΄ΠΎ 67 % ΠΏΠΎ ΡΡΠ°Π²Π½Π΅Π½ΠΈΡ ΡΠΎ ΡΠΊΠ°Π½ΠΈΡΡΡΡΠ΅ΠΉ ΡΠ»Π΅ΠΊΡΡΠΎΠ½Π½ΠΎΠΉ ΠΌΠΈΠΊΡΠΎΡΠΊΠΎΠΏΠΈΠ΅ΠΉ. ΠΠ΅ΡΠΎΠ΄ Π°ΡΠΎΠΌΠ½ΠΎ-ΡΠΈΠ»ΠΎΠ²ΠΎΠΉ ΠΌΠΈΠΊΡΠΎΡΠΊΠΎΠΏΠΈΠΈ Π±Π»Π°Π³ΠΎΠ΄Π°ΡΡ ΠΏΡΠΎΡΡΡΠ°Π½ΡΡΠ²Π΅Π½Π½ΠΎΠΉ ΡΡΡΡ
ΠΌΠ΅ΡΠ½ΠΎΠΉ Π²ΠΈΠ·ΡΠ°Π»ΠΈΠ·Π°ΡΠΈΠΈ ΠΈ Π²ΡΡΠΎΠΊΠΎΠΉ ΡΠΎΡΠ½ΠΎΡΡΠΈ (ΠΏΠΎ XY Β±β0,2 Π½ΠΌ, ΠΏΠΎ Z Β±β0,03 Π½ΠΌ) ΡΠ°ΡΡΠΈΡΡΠ΅Ρ Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎΡΡΠΈ ΠΏΡΠΈΠΌΠ΅Π½Π΅Π½ΠΈΡ ΠΈΠ½Π΄Π΅Π½ΡΠΈΡΠΎΠ²Π°Π½ΠΈΡ Ρ ΠΏΡΠΈΠΌΠ΅Π½Π΅Π½ΠΈΠ΅ΠΌ Π½ΠΈΠ·ΠΊΠΈΡ
Π½Π°Π³ΡΡΠ·ΠΎΠΊ.ΠΡΠ΅Π΄Π»ΠΎΠΆΠ΅Π½ ΡΠΏΠΎΡΠΎΠ± ΠΏΠΎΠ²ΡΡΠ΅Π½ΠΈΡ ΡΠΎΡΠ½ΠΎΡΡΠΈ ΠΎΠΏΡΠ΅Π΄Π΅Π»Π΅Π½ΠΈΡ KICΒ Π·Π° ΡΡΡΡ ΠΈΠ·ΠΌΠ΅ΡΠ΅Π½ΠΈΡ ΠΌΠΈΠΊΡΠΎΡΠ²ΡΡΠ΄ΠΎΡΡΠΈ Ρ Π½Π°Π½ΠΎΠΈΠ½Π΄Π΅Π½ΡΠΎΡΠ°. Π£ΡΡΠ°Π½ΠΎΠ²Π»Π΅Π½ΠΎ, ΡΡΠΎ Π½Π°Π½ΠΎΠΈΠ½Π΄Π΅Π½ΡΠΈΡΠΎΠ²Π°Π½ΠΈΠ΅ ΠΏΡΠΈΠ²ΠΎΠ΄ΠΈΡ ΠΊ ΠΏΠΎΠ²ΡΡΠ΅Π½ΠΈΡ ΡΠΎΡΠ½ΠΎΡΡΠΈ ΠΎΠΏΡΠ΅Π΄Π΅Π»Π΅Π½ΠΈΡ KICΒ Π½Π° 16β23 % ΠΈ ΠΈΡΠΊΠ»ΡΡΠ°Π΅Ρ ΠΎΠ±ΡΠ°Π·ΠΎΠ²Π°Π½ΠΈΠ΅ ΠΌΠΈΠΊΡΠΎΡΡΠ΅ΡΠΈΠ½ Π² ΠΎΡΠΏΠ΅ΡΠ°ΡΠΊΠ΅
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