90 research outputs found
The technology of radial drilling as a method of improved oil recovery
Currently, the volume of difficult oil in the world is increase and amasses close to 70%. Electric submersible pumps (ESPs) and jack pumps (SRP) used ever more 80% of the wells. Mechanical method of production is not always effective due to the low coefficient of efficiency pump units operating in marginal wells. There is a limit for well production rate below which produce oil is technically impossible or economically unprofitable. Many wells, currently stopped oil production due to unprofitability of oil wells with hard to recover reserves. It leads to their conservation or liquidation. The number of such wells is of these wells is about 25000-30 000. Pressure communication suffers from lack of quality in a "well-formation". It is caused by technological problems in the construction of wells, particularly in the productive intervals. It leads to excessive pressure in the reservoir, and then plugging reservoir mud filtrate or the cement slurry reaches a depth of several meters
XYZ-polarisation analysis of diffuse magnetic neutron scattering from single crystals
Studies of diffuse magnetic scattering largely benefit from the use of a
multi-detector covering wide scattering angles. Therefore, the different
contributions to the diffuse scattering that originate from magnetic, nuclear
coherent, and nuclear spin-incoherent scattering can be separated by the
so-called XYZ-polarization analysis. In the past this method has been
successfully applied to the analysis of diffuse scattering by polycrystalline
samples of magnetic disordered materials. Single crystal studies that exploit
the vector properties of spin correlations are of particular interest for
furthering our understanding of frustration effects in magnetism. Based on the
symmetry properties of polarised scattering a suitable extension of the
conventional XYZ method has been derived, which allows for the complete
separation and the analysis of features of diffuse magnetic scattering from
single crystals.Comment: 6 pages 2 figures, revised as published, one Eq. removed, minor
corrections, typos correcte
Characterization of a ballistic supermirror neutron guide
We describe the beam characteristics of the first ballistic supermirror
neutron guide H113 that feeds the neutron user facility for particle physics
PF1B of the Institute Laue-Langevin, Grenoble (ILL). At present, the neutron
capture flux density of H113 at its 20x6cm2 exit window is 1.35x10^10/cm^2/s,
and will soon be raised to above 2x10^10/cm^2/s. Beam divergence is no larger
than beam divergence from a conventional Ni coated guide. A model is developed
that permits rapid calculation of beam profiles and absolute event rates from
such a beam. We propose a procedure that permits inter-comparability of the
main features of beams emitted from ballistic or conventional neutron guides.Comment: 15 pages, 11 figures, to be submitted to Nuclear Instruments and
Methods
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