17 research outputs found
Galvanomagnetic properties of surface electrons over liquid helium
The aim of the paper is to study the galvanomagnetic properties of surface electrons in temperature interval 0,4-1,6 K. The absolute values of longitudinal magnetoresistance, cross magnetoresistance and longitudinal magnetic conductivity have been obtained. The transducer of second sound has been created. The features of transfer properties of system explained by quantum processes have been discoveredAvailable from VNTIC / VNTIC - Scientific & Technical Information Centre of RussiaSIGLERURussian Federatio
Small-angle scattering of neutrons on normal and superfluid liquid helium
Experiments on small-angle scattering of neutrons on liquid helium at temperatures of 1.0–5 K at the ISIS pulsed neutron source (England) are reported. Detailed measurements of the angular distribution of the scattered neutrons reveal a significant change in the temperature dependence of the second moment of the pairwise correlation function (the first derivative of the angular distribution for small scattering angles). At high temperatures the angular distribution of the scattered neutrons follows the classical description for small-angle scattering, but at temperatures below the λ-point, quantum mechanical behavior is observed (scattering of neutrons on quantum fluctuations). It is confirmed experimentally that over the entire temperature range the neutron scattering cross section at zero angle is determined by classical thermodynamic fluctuations in the density
Expanding Technological Capabilities of The Combined Hardening of Steel by Deformation
The technology of wave deformation hardening of metal machine parts is described, which allows obtaining a hardened surface layer up to 10 mm deep. The article presents the results of studying the microstructure and hardness of the samples strengthened as a result of chemical heat treatment and combined hardening consisting of preliminary wave deformation hardening and subsequent chemical heat treatment of structural alloyed steel 15CrС2Ni2Mg. It is established that a preliminary impact on the cemented material by a deformation wave contributes to creating uniformly high packing density of martensite, as well as smaller sizes of martensite needles in the subsurface layer and at the border of the cemented layer, in the core of the sample and contributes to the absence of large-needle martensite. Applying this technology allows forming a high uniform hardness at 65 HRC at a depth of 1.5 mm, with its gradual reduction to the core of the sample, while maintaining a high level of toughness. The results obtained allow recommending wave deformation hardening and the combined technology based on it to improve the performance properties of variable machine parts that operate under the conditions of sliding friction and impact loads
Data from: Segregated water observed in a putative fish embryo cryopreservative
Development of new cryopreservation strategies has major potential in medicine and agriculture and is critical to the conservation of endangered species that currently cannot be preserved. A critical property of any potential cryopreservative solution is its ability to prevent cell-damaging ice formation during cooling and subsequent heating. This study focuses on the freezing behaviour of promising model cryoprotective solutions. We perform neutron scattering analysis, combined with computer modelling, of the water structure after quench cooling these solutions. It is found that water in this solution forms nano-clusters encapsulated by the surrounding matrix of cryoprotectant solute molecules. We posit that these small volumes inhibit ice formation, because water does not have space for the structural relaxation required to crystallize on the timescale of the cooling process
cryopreservation EPSR folder
This is the entire EPSR folder for the data and simulations and analysis shown in this paper
cryopreservation EPSR folder
This is the entire EPSR folder for the data and simulations and analysis shown in this paper
Differential cross sections for fully protiated sample.
<p>Heating after initial quench cooling. The crystallisation transition occurs between 160 K and 170 K.</p