The materials of The International Scientific – Practical Conference is presented below.
The Conference reflects the modern state of innovation in education, science, industry and social-economic sphere, from the standpoint of introducing new information technologies.
It is interesting for a wide range of researchers, teachers, graduate students and professionals in the field of innovation and information technologies.
The aim of the article was to study the hardness of a metal surface modified with ultrafine particles of minerals by two different methods (instrumental indentation and Vickers hardness measurement) and a comparative analysis of the measurement results obtained by these methods.Standard Vickers hardness measurements at loads of 0.025, 0.1, and 0.5 kgf showed a qualitative difference between the hardness values of the two samples modified with different mixtures of ultrafine particles of minerals and a large heterogeneity of the hardness values over the area. By the method of instrumental hardness, standard measurements were performed without preliminary selection of the indentation site (at a load of 1.05 N) and measurements during indentation into even sections (at low loads of 10 mN).It is noted that the high precision of measurements implemented by instrumental indentation, due to the large roughness of the samples, leads to large values of the error in calculating the measurement results. An additional difference in the results of measurements performed by two methods at shallow indentation depths may be due to the fact that the object under study has a complex structure consisting of a metal matrix and particles distributed over the depth of the sample. A possible way out of the situation lies in the transition from the use of hardness measures when calibrating instruments to standard samples of properties for which the constancy of mechanical properties in the measured range of indentation depths will be ensured, but which are not yet available in research practice.
The authors investigate aluminum shaped charge jet (SCJ) penetration into an aluminum alloy target at 8–11 km/s velocities. The analysis of kinetics, penetration parameters and structures of cavern surfaces formed after the penetration show that at velocities exceeding 9–11 km/s, the hydrodynamic character of the penetration changes due to the melting of the interacting materials. When during the penetration process SCJ velocity exceed 9 km/s, porous layer of aluminum nanospheres with 20–100 nm in diameter form in the penetration region. The results obtained are appropriate for developing spacecraft shield protections against most dangerous space fragments.
We review epitaxial formation, basic properties, and device applications of a novel type of nanostructures of mixed (0D/2D) dimensionality that we refer to as quantum well-dots (QWDs). QWDs are formed by metalorganic vapor phase epitaxial deposition of 4–16 monolayers of InxGa1xAs of moderate indium composition (0.3 < x < 0.5) on GaAs substrates and represent dense arrays of carrier localizing indium-rich regions inside In-depleted residual quantum wells. QWDs are intermediate in properties between 2D quantum wells and 0D quantum dots and show some advantages of both of those. In particular, they oer high optical gain/absorption coecients as well as reduced carrier diusion in the plane of the active region. Edge-emitting QWD lasers demonstrate low internal loss of 0.7 cm1 and high internal quantum eciency of 87%. as well as a reasonably high level of continuous wave (CW) power at room temperature. Due to the high optical gain and suppressed non-radiative recombination at processed sidewalls, QWDs are especially advantageous for microlasers. Thirty-one m in diameter microdisk lasers show a high record for this type of devices output power of 18 mW. The CW lasing is observed up to 110 C. A maximum 3-dB modulation bandwidth of 6.7 GHz is measured in the 23 m in diameter microdisks operating uncooled without a heatsink. The open eye diagram is observed up to 12.5 Gbit/s, and error-free 10 Gbit/s data transmission at 30 C without using an external optical amplifier, and temperature stabilization is demonstrated.
Adsorption of fluids in nanoporous media causes mechanical stresses which results in deformation. This phenomenon is ubiquitous and its magnitude depends on the pore size and geometry. Adsorption and adsorption-induced deformation are typically modeled in slit-shape or convex (cylindrical or spherical) pores. However, many porous materials are composed of spherical grains, so that the pores are formed by the intergranular spaces between the convex solid surfaces. Here we present a first theoretical study of adsorption-induced deformation in non-convex pores, in particular we studied the templated mesoporous carbons. The model is based on classical density functional theory within the local density approximation applied to the description of hard sphere interactions. We predict the adsorption isotherms and solvation pressure isotherms for nitrogen adsorption in CMK-3 carbons. The shape of adsorption isotherm matches the shape of experimental isotherm. The predicted solvation pressure isotherms are qualitatively different from the solvation pressure isotherms in cylindrical pores. We attribute this difference to formation of liquid bridges between the adjacent rods. Our results suggest that adsorption-induced deformation in materials with non-convex pores cannot be predicted within the existing models. These results may shed some light on understanding adsorption-induced deformation of consolidated granular media.
Russia is one of the largest carbon emitters in the world, possessing huge resources of both fossil fuels and zero-carbon energy sources. The Paris Agreement targets require substantial efforts to limit global warming to “well below 2 °C”. Energy-economic modeling provides sound conclusions that continuation of existing energy and climate policy will lead to stabilization of energy carbon emissions in Russia at the current level in 2010–2050 (about 30% below 1990). Stronger mitigation policies could gradually reduce domestic energy CO2 emissions by 61% from 2010 to 2050 (75% below 1990). Deep decarbonization policies with even more ambitious commitments could ensure an 83% reduction in energy CO2 emissions from 2010 levels (88% below 1990) by 2050. All key sectors (energy, industries, transport, and buildings) can play a substantial role in decarbonizing the national economy. However Russia’s historical reliance on domestic consumption and exports of fossil fuels creates strong barriers to decarbonization. Emission reduction costs are expected to be below 29 USD/tCO2 by 2030, 55 USD/ tCO2 by 2040, and 82 USD/tCO2 by 2050 in the most ambitious decarbonization scenario. The results of this study provide insights into how Russia can enhance its ambitions to implement the Paris Agreement and contribute to global efforts toward building a climate-neutral economy by 2050.
In the paper, we propose a model describing a change of charge state of MIS structures and sensors based on them being under influence of both a radiation ionization and high-field injection of electrons from the semiconductor. The model proposed takes into account the interaction of injected electrons with holes generated by the radiation and high-field ionization and captured by traps in the SiO2 film at the interface with the semiconductor. Besides, the model takes into consideration the generation of the surface states at annihilation of a fraction of holes during their interaction with injected electrons. We demonstrate that MIS sensor, being under high-field injection of electrons into the dielectric film by constant current, can be utilized to control intensity of radiation by determining the current of radiation ionization using time dependence of voltage across the sensor using the model proposed. We have ascertained that in case the MIS sensor being under high-field injection of electrons, a significant raising of the dose sensitivity of MIS sensors of the absorbed dose has been possible. However, at that working life and dose range of MIS sensors could be significantly smaller.
In the last 50 years, the biosphere, upon which humanity depends, has been altered to an unparalleled degree. The current economic model relying on fossil resources and addicted to “growth at all costs” is putting at risk not only life on our planet, but also the world’s economy. The need to react to the unprecedented COVID-19 crisis is a unique opportunity to transition towards a sustainable wellbeing economy centered around people and nature. After all, deforestation, biodiversity loss and landscape fragmentation have been identified as key processes enabling direct transmission of zoonotic infectious diseases. Likewise, a changing climate has profound implications for human health. Putting forward a new economic model requires transformative policies, purposeful innovation, access to finance, risk-taking capacity as well as new and sustainable business models and markets. But above all we need to address the past failure of our economy to value nature, because our health and wellbeing fundamentally depends on it. A circular bioeconomy offers a conceptual framework for using renewable natural capital to holistically transform and manage our land, food, health and industrial systems with the goal of achieving sustainable wellbeing in harmony with nature. Within the framework of the Sustainable Markets Initiative, under the leadership of His Royal Highness The Prince of Wales, a 10-Point Action Plan to create a circular bioeconomy is proposed below. The Action Plan is a response to The Prince of Wales’ call to invest in nature as the true engine for our economy. The Action Plan, guided by new scientific insights and breakthrough technologies, is articulated around six transformative action points further discussed below and four enabling action points, which mutually reinforce each other.
A model of the electric field enhanced thermal (thermo-field) emission of electrons from the metal cathode substrate into a thin insulating film on its surface is developed. A system of equations for the cathode surface temperature in the arc discharge and the electric field strength in the film, providing the required discharge current density, is formulated. It is shown that existence of the insulating film can result in a considerable reduction of the cathode temperature in the discharge due to lower potential barrier height at the metal-insulator boundary than at the metal-discharge boundary in case of the cathode without the film. It is found that due to an enhancement of the thermal emission of electrons into the film by the electric field generated in it, an additional decrease in the cathode temperature by about 100 K takes place.
Based on the obtained experimental data, a model is developed for the processes of a variation in the charge state of MIS (metal–insulator–semiconductor) structures under the concurrent influence of high-field tunneling electron injection and radiation. The model takes into account the interaction between injected electrons and charges appearing in the dielectric film due to radiation and high-field ionization. It is shown that some holes may be annihilated during the interaction between injected electrons and holes trapped in a SiO2 film, thus leading to the formation of surface states at the interface with silicon. The effect of the electric-field intensity and injection current density on the generation and annihilation of positive charge and the formation of surface states under radiation is studied. The effect of charge processes occurring in the insulator film of a MIS structure under the concurrent action of radiation and high-field electron injection on a change in the threshold voltage of MIS devices and radiation sensors based on them is considered.