[en] The results are presented of a Monte-Carlo simulation of nonstationary transport and storage of ultracold neutrons (UCN) in curved vertical and horizontal neutron guides of rectangular cross section with a reflector at the exit end. Included were neutron losses due to capture and diffuse neutron scattering by imperfectly smooth reflecting guide wall surfaces. It is shown that a significant part of UCN, reaching the end section of the neutron guide (30-50%) may be trapped in a small volume 1-2 l. 3 refs., 6 figs

[en] Small absolute value of crystal electric field gradient together with f-p hybridization are reasons of an anomalous quadrupolar phenomena in ternary compounds R-C-Si (R=Pr,Nd) of 1-2-2 series. The quadrupolar Kondo-effect takes place in PrCu₂Si₂ compound. There are two variants of crystal field (CF) in NdCu₂Si₂ compound due to temperature. The anomalous CF with significant mixing part is realized at high temperatures. The normal CF without mixing component takes place at low temperatures. (author)

[en] The results are presented of the Monte Carlo simulation of the transport of very cold (VCN) and ultracold neutrons (UCN) in straight and curved vertical neutron guides with a rectangular cross section in the presence of neutron losses due to neutron capture and diffuse scattering on imperfectly smooth reflecting surface of the guides wall. The gravitational neutron deceleration and bending of neutron trajectories are taken into account rigorously. The nonstationary storage of UCN in experimental chambers is modelled for a low periodic or aperiodic pulse neutron source. 14 refs., 7 figs

[en] The results of Monte Carlo simulation of the transport of ultracold neutrons (UCN) through spectral filters of different geometric forms are presented. These filters are intended for use in experiments, in which the presence of neutrons with energies higher than some critical energy is detrimental to an unambiguous interpretation of the experimental results. The presented results may be helpful in choosing the proper filter configuration for a particular experiment. 10 refs., 20 figs., 2 tabs

[en] A new method for the calculation of splitting of the fundamental local modes was proposed. It takes account of the relaxation of metal atoms around the defects and the elastic interaction of the deformation fields. This approach allows one to explain the neutron spectroscopy results, which was impossible to explain by the force constant approach. (author)

[en] The results are presented of a Monte Carlo simulation of nonstationary transport of ultracold neutrons (UCN) in straight and curved neutron guides of rectangular cross section for different suppositions about losses and the character of diffuse neutron scattering by imperfectly smooth reflecting surfaces. The storage of UCN in experimental chambers is modelled for the case of a low periodic or aperiodic pulse neutron source for production of UCN. 28 refs., 7 figs

[en] Parameters of hamiltonian of crystalline field of compouns satisfactorily decribing both neutron spectra and experimental data on magnetic susceptibility of monocrystal are determined on the ground of data on Nd₂CuO₄ polycrytalline specimen

[en] On the base of magnetic inelastic neutron scattering on polycrystalline Nd₂CuO₄ the set of crystal electric field parameters has been determined. These parameters satisfactorily describe both neutron spectra and experimental data on magnet susceptibility of monocrystal of this compound. Strong hybridization of ground and first excited multiplets has been discovered. Predictional ability of the superposition model in nonmetals is confirmed. Quantitative significance of molecular field parameter has been obtained. 13 refs.; 3 figs

[en] High densities of ultracold neutrons can be stored in experimental volumes if one uses pulse thermal neutron source with a low repetition rate, a very low temperature converter, a high quality curved neutron guide, and a shutter at the entrance window of the storage volume. Some results of a Monte Carlo simulation are presented of the nonstationary transport of very cold (VCN) and ultracold neutrons (UCN) in straight and curved horizontal, and vertical neutron guides with a rectangular cross section, in the presence of neutron losses due to neutron capture and diffuse scattering on imperfectly smooth reflecting surface of the guides wall. The gravitational neutron deceleration and bending of neutron trajectories are taken into account rigorously. The nonstationary storage of UCN in experimental chambers is modelled for a low periodic or aperiodic pulse neutron source. (author)

[en] The vibration spectrum of highly dispersed nickel at 80 and 300 K is obtained by difference spectroscopy of inelastic, incoherent neutron scattering. An analysis of the experimental data shows that the inelastic incoherent neutron scattering cross section and the functions of the weighted densities of the small particle vibrational states can be described in sufficiently detail on the basis of modern concepts of the vibrational spectrum of a thin plate. It is shown that the mixed mode region is the most difficult one for analysis