Phys.org July 4, 2023 To address overheating in microchip-based devices researchers in Russia 3D printed a model of a composite radiator with different boron nitride fillings. The measured absolute values of the thermal conductivity of such a composite in the temperature range of 3–300 K strongly depend on the concentration of boron nitride. Filling the photopolymer with boron nitride led to a change in the behavior of the volt–current curves, which might have been associated with the occurrence of percolation currents during the deposition of boron nitride. The ab initio calculations showed the behavior and spatial orientation of BN flakes […]
Tag Archives: S&T Russia
Nanostructure strengthens, de-ices, and monitors aircraft wings, wind turbine blades, and bridges
Phys.org December 22, 2022 Researchers in Russia have developed nanostructured sensor made of carbon nanotubes which generates heat under electrical current. When it is embedded in a composite, it leaves the composite’s thickness unaffected, other characteristics unimpaired and does not create undesirable pores. It can serve as a sensor for structural health monitoring or a heater for anti-icing or de-icing purposes. By applying an electrical current to the carbon nanotube layer and monitoring the signal, it is possible to keep track of the structure’s deterioration and avert disaster by anticipating breakage. Electricity can also be used for heating to de-ice […]
Researchers propose new technology for aviation materials to allow for adjusting their properties
Phys.org September 19, 2022 Most of the carbon fiber composites used currently are based on epoxy resin and other non-melting, insoluble materials that are not recyclable. Researchers in Russia have created a new composite material based on engineering thermoplastic polymers and carbon fiber. For matrix they used polyethersulfone powder which has excellent mechanical properties and resistant to high temperatures, steam, and various chemicals. Unlike epoxy it is recyclable. They determined the optimal content of carbon fibers for airborne composites based on polyethersulfone to be 60–70% of the total weight of the structure. The properties of the material can be adjusted […]
Russia launches classified military satellite
Phys.org November 25, 2021 According to the Russian defense ministry, a Soyuz rocket carrying a classified payload blasted off from the Plesetsk cosmodrome in northern Russia in the early hours of Thursday morning. It is believed to be part of the Kremlin’s early warning anti-missile system. It did not provide further details. According to the Spaceflightnow website, which covers space launches, the launch could be delivering a Tundra satellite. Russia has previously launched Tundra satellites in 2015, 2017 and 2019, according to Interfax…read more.
Chemists develop a new technology to prevent lithium-ion batteries from catching fire
EurekAlert March 3, 2021 Researchers in Russia have developed a new approach to overcharge protection of Li-ion cells, which is provided by use of electrically conductive polymer that change electrical conductivity from conductive to insulating stage. A layer of the polymer deposited between the LiFePO4 -based cathode material and current collector acts as a chemical circuit breaker increasing the electrode resistance more than 20 times when the cell voltage exceeds 4.2 V. At 5 V overcharge it allows reversible charge-discharge of the cell without developing adverse process, while at 6 V overcharge it terminates the cell operation before electrolyte decomposition […]
Experimental evidence of an intermediate state of matter between a crystal and a liquid
EurekAlert January 19, 2021 Researchers in Russia present a detailed analysis of their experimental study, which shows clear evidence of a two-stage melting process of a quasi-two-dimensional dusty plasma system in a high-frequency gas discharge. They accurately calculated global parameters of the orientational and translational order, as well as their susceptibilities to determine two critical points, related to “solid-to-hexatic” and “hexatic-to-liquid” phase transitions. The nature of the emerging defects and changes in their mutual concentration, in addition to the estimate of core energy of free dislocations also counts in favor of the formation of an intermediate hexatic phase. These results […]
Self-diagnostic carbon nanocomposites
Nanowerk November 23, 2020 Studies have shown that carbon nanomaterials can increase required mechanical properties with relatively small addition amounts, all the while allowing the final material to be electrically conductive and piezoresistive in nature but their incorporation into large scale production requires intensive facility upgrades. Researchers in Russia used masterbatches and industrially available, inexpensive manufacturing techniques to examine how the addition of carbon nanoparticles can change the electric conductivity of polymer matrices. Essentially, the use of such materials has the potential to replace sensors in weight critical systems such as aircraft structures, with the material itself being able to […]
Scientists Discover Exotic New Mineral Forged in The Furnace of a Russian Volcano
Science Alert November 18, 2020 The ‘Great Tolbachik Fissure Eruption’ of 1975–1976, and a second, lesser follow-up that took place between 2012–2013 opening rocky terrain to 130 unknown minerals which were identified. researchers in Russia have identified the latest one, petrovite, a sulfate mineral that takes shape as blue globular aggregates of tabular crystals, many holding gaseous inclusions. The copper atom in the crystal structure of petrovite has an unusual and rare coordination of seven oxygen atoms. At the chemical level, petrovite represents a new type of crystal structure. Its molecular framework – consisting of oxygen atoms, sodium sulphur and […]
No losses: Scientists stuff graphene with light
EurekAlert November 16, 2020 Researchers in Russia developed a technique to achieve 90% energy conversion from the pump laser field to the surface plasmon polaritons (SPPs) on the base of the hybrid optoplasmonic multi‐level scheme of near‐resonant interaction with semiconductor quantum dots (QDs) placed in the proximity of a graphene surface. Using numerical simulations and semiclassical approach for the light–matter interaction they found that maximum efficiency of SPP generation is achieved in strong coupling conditions for a stationary regime of SPP‐QD interaction. The technique can be used for converting energy in solar cells, and nano and bio-object detection…read more. TECHNICAL […]
Russia Conducts Direct-Ascent Anti Satellite Weapon from Plesetsk
Defense Update April 22, 2020 Russia has been engaged in direct ascent anti-satellite (DA-ASAT) anti-satellite weapon tests in the past months. On April 15, a missile launch from the Plesetsk test site on the arctic circle. Russian media sources reports said the missile tested called ‘Nudol’ has reached over 7,000 m/sec, thus positioned in the ‘hypersonic‘ category. Prior to the test, large airspace along the missile’s flight path was closed, with an area typical for a two-staged missile. Other tests of anti-satellite weapon systems were previously conducted under the “Sistema A-235 / RTTS-181M Nudol” program which has been tested at […]