Dispersion of the multiplicity distribution in hadron-nucleus collisions

It is argued that the measurements of the dispersion of the multiplicity distribution in hadron-nucleus collisions favour the processes of particle production in a sequence of collisions of the incident hadron with target nucleons. On the other hand, generation of particles on groups of nucleons treated as single units leads to large discrepancies.     

Local composition in binary mixtures of Lennard-Jones fluids with differing sizes of components

Three Lennard-Jones binary liquid mixture systems obeying Lorentz-Berthelot rules, but having differing component sizes and energy parameters, have been used to calculate the local fractions of the two components around each type of central particle over the entire composition range from molecular-dynamics data. It is found that well-defined local fractions can be determined even in the case where the size difference between the particles is large. The results obtained are compared with values predicted by the Wilson and NRTL equations. It is confirmed that the NRTL equation gives satisfactory agreement only in the case of mixtures of components having the same size parameters. A new correlation is proposed by a modification of the NRTL equation. This correlation can predict reasonably well local-fraction data for all the Lennard-Jones liquid mixtures studied so far.     

Randomly flashing diffusion: Asymptotic properties

The theory of abstract Markov operators and semigroups is applied for studying asymptotics of a randomly flashing diffusion process. The probability distribution of the process is determined by a set of two partial differential equations and sufficient conditions for the existence of a stationary solution of the equations are formulated, and convergence of solutions to the stationary solution is proved.     

Crystal and magnetic structure of CoMnGe,CoFeGe, FeMnGe and NiFeGe

The crystal and magnetic properties of CoMnGe, CoFeGe, FeMnGe and NiFeGe compounds are investigated with X-ray, neutron diffraction, magnetometric and Mössbauer effect methods. All compounds have hexagonal Ni₂In-type crystal structure and ferromagnetic properties at low temperatures (except for NiFeGe). Neutron diffraction experiments indicate that the compounds CoMnGe and CoFeGe have a collinear magnetic structure while FeMnGe a noncollinear. The magnetic moments are localized only on Mn and Fe atoms and lie in the basal plane.     

Capacities as conformal quasi-invariants on pseudo-riemannian manifolds

A class of capacities is introduced on pseudo-riemannian manifolds. They arise as a natural counterpart of the well-known plane quasiconformal capacities and their higher dimensional analogues which have been studied extensively in the recent years by F.W. Gehring, R. Kühnau and others. The capacities in question are shown to be either conformal invariants or conformal quasi-invariants, and, in the latter case, exact bounds are established. We thus arrive at the notion of quasiconformal mappings of pseudo-riemannian manifolds, which correspond to the inhomogeneous media. These mappings are studied briefly and the physical interpretation of some of the capacities in question is also given.     

Normal coordinate analysis of M2O7 systems with C2v symmetry (pyrophosphates and -arsenates) intramolecular forces in a urey-bradley-shimanouchi force field

The vibrational spectra of nickel and magnesium α-pyrophosphates and of potassium and sodium α-pyroarsenates were found. A normal coordinate analysis was carried out for both P₂O₇ and As₂O₇ molecular systems using the force field of the Urey-Bradley-Shimanouchi type and the C_2v symmetry model. On the basis of the results obtained the significant differences between the temperatures of the α/β phase transitions observed for Mg (68 °C) and Ni (565 °C) pyrophosphates have been explained.