Реферат: We discuss here some results of our SANS studies of structure of the impurity-helium condensates, gel samples, prepared by condensation of the gas mixture 4He + 2% of the impurity (D2, O2, vapors of D2O or C2D5OD) on the surface of superfluid He-II cooled below 1.8 K. The impurity nanoclusters covered by a layer of solidified He form the backbone (a dispersive system) of the gel, and liquid helium in the nanopores between the cluster aggregates serves as a dispersion medium.
On the equilibrium density of ions in raining clouds
Автор(ы): Chikina I.*Shikin V. B.*
Объем документа: С. 54-55
МРНТИ: 29.17*
Ключевые слова: плотность ионов*зарядовые явления*полупроводник*
Реферат: On e of the debatable issues in meteorology is the source of enhanced ion density in storm clouds. This source is obviously related in some way to the density of rain drops in the storm cloud. It is also clear that all charging phenomena should involve free protons which are the highest mobility ions in the problem. Discussed in the present paper is the approach providing a ?nite ion density in the system of rain drops. The corresponding model for the storm cloud can be referenced as a \"proton semiconductor\" by analogy with electronic crystal semiconductors where charge is carried by light particles, i.e. electrons and holes.
Application of impedance spectroscopy for studying of charged nanoclusters in impurity-helium condensates
Автор(ы): Pelmenev A. A.*Boltnev R. E.*Bykhalo I. B.*Krushinskaya I. N.*
Реферат: A gas jet consisting of a mixture of helium and impurity ( 1% of H2, N2, Ne, Kr, Xe, etc.) gases was directed onto the surface of superfluid helium (HeII) contained in the glass beaker. During condensation of the impurity particles in the bulk superfluid helium the so-called impurity-helium condensate is formed [1]. Recently in 2013, charges were detected for the first time during destruction of the nitrogen-helium samples [2]. For further investigations it was proposed to use methods of the impedance spectroscopy. We used a sensor of planar geometry with two conductive meanders (the sensor capacity was of 7.9 pF).
Turbulence on the surface of cryogenic liquids in restricted geometry of experimental cell
Автор(ы): Abdurakhimov M. Yu.*Brazhnikov G. V.*Kolmakov A. A.*Levchenko I. A.*
Реферат: We report on results of experimental investigations of nonlinear phenomena on the surface of liquid hydrogen and helium. The experiments were carried out at temperature T=1.7 K for superfluid helium and at T=15 K for liquid hydrogen. Helium and hydrogen gases were condensed into the copper cup of inner diameter 30 mm (helium) and 60 mm (hydrogen) and depth 4 mm.
Unconventional phase transitions on HD and O2 cryocrystals
Автор(ы): Crespo Y.*Laio A.*Santoro G. E.*Fabrizio M.*Scandolo S.*Тоsatti E.*
Реферат: Unconventional phase transitions on HD and O2 cryocrystals Both HD and O2 are molecular solids with an exceedingly well explored phase diagram under pressure. In this talk we focus in two unusual phase transition taking place at high pressures. First we study the unusual reentrant phase transition that the phase diagram of HD exhibits near 50 Gpa where a rotationally ordered (\"broken symmetry\") crystalline phase surprisingly transforms into a rotationally \"disordered\" high-symmetry phase upon cooling.
Vacancy assisted flow of solid helium
Автор(ы): Giorgio Benedek*Anton Kalinin*Pablo Nieto*J. Peter Toennies*
Реферат: The idea that solid helium might become a supersolid goes back to Andreev and Lifshiz [1]. The 2004 observation of supersolidity in torsional oscillator experiments by E. Kim and M. Chan [2] started an extensive worldwide series of related investigations. Since the report by D. Y. Kim and M. Chan in 2012.
Optical spectroscopy and current detection during warm-up and destruction of impurity-helium condensates
Автор(ы): Krushinskaya I. N.*Boltnev R. E.*Bykhalo I. B.*Pelmenev A. A.*Khmelenko V. V.*Lee D. M.*
Реферат: It is well known that deposition of rare gases (RG) passed through electrical discharge area onto a cold ( 4 K) surface, or irradiation of cryofilms by energetic particles (electrons, protons, or photons with energies of 20 eV - 4 MeV) can cause formation and stabilization of neutral radicals and ions. Recent experiments have revealed ion currents accompanied by luminescence during destruction of nitrogenhelium condensates prepared by condensation of nitrogen-helium gas mixtures (after passing through a radio frequency RF discharge zone) into superfluid helium (HeII) bulk.
Penetration of charges through the surface of water
Автор(ы): Levchenko A. A.*Khramov D. A.*Shikin V. B.*Likhter A. M.*Gryasnova V. A.*
Реферат: The general goal of this project is experimental investigation of the properties of intrinsic (electric) The general problem of this project is experimental investigation of the properties of intrinsic (electric) carriers in water and development of statistics of liquid electrolytes by analogy with semiconductor statistics. In water and development of statistics of liquid electrolytes by analogy with semiconductor statistics.
Phase diagram of polymerizing nitrogen - a theoretical prediction
Реферат: Polymerization of nitrogen molecules in both solid and liquid phases, which was discovered in dynamic and static experiments, and predicted in ab initio simulations, stimulated discussion on a new configuration of phase diagram of nitrogen at high pressures. We consider the high-pressure phase diagram of solid nitrogen, which has long been discussed in theoretical studies, and only in the last decade began to investigate experimentally.
Phonon spectrum and vibrational characteristics of l inear nanostructures in solid m atrices
Автор(ы): Gospodarev I. A.*Manzhelii E. V.*Minakova K. A.*Syrkin E. S.*Feodosyev S. B.*
Реферат: Nowadays, the structures with one-dimensional or quasi-one-dimensional nanoinclusions in various crystalline or amorphous matrices attract attention of researchers. Under real relations between the interactions of the atoms of embedded quasi-periodic systems with each other and with the atoms of the matrix, the features, inherent to one-dimensional systems, can appear in the quasi-particle spectra of these structures.
