731 research outputs found
Quantum discord in spin-cluster materials
The total quantum correlation (discord) in Heisenberg dimers is expressed via
the spin-spin correlation function, internal energy, specific heat or magnetic
susceptibility. This allows one to indirectly measure the discord through
neutron scattering, as well as calorimetric or magnetometric experiments. Using
the available experimental data, we found the discord for a number of binuclear
Heisenberg substances with both antiferro- and ferromagnetic interactions. For
the dimerized antiferromagnet copper nitrate Cu(NO_3)_2*2.5H_2O, the three
independent experimental methods named above lead to a discord of approximately
0.2-0.3 bit/dimer at a temperature of 4 K. We also determined the temperature
behavior of discord for hydrated and anhydrous copper acetates, as well as for
the ferromagnetic binuclear copper acetate complex [Cu_2L(OAc)]*6H_2O, where L
is a ligand.Comment: 7 pages, 6 figure
Neural geological-genetic and radiogeochemical forecast model of oil-bearing fields
In recent years, oil and gas exploration are increasingly turning to direct methods to identify accumulations of hydrocarbons (magnetometry, radiometry, geochemical methods, etc.). Similar works are tested high in the Tomsk region, near the Ob basin. In this paper we present some results of testing of geological and genetic models and radiogeochemical occurrence of hydrocarbons in relation to various oil and gas complexes, with the development of neural network methods of analysis and forecasting, formulated proposals for their integrated use
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