Table of contents

The role of short-range order (SRO) in strongly correlated metallic systems is discussed. Magnetic neutron scattering experiments show that SRO is a universal property of such systems. Different theoretical approaches to the analysis of SRO are considered. Microscopic models based on infinite-dimensional lattice solutions (the Monte Carlo variational technique, the 1/D+1/D² expansion for the Gutzwiller trial wave function, and the dynamical mean-field theory) do not correctly describe SRO in strongly correlated systems. A variational theory of SRO in Fermi systems is presented in which, in addition to Gutzwiller's variational parameter, a set of new parameters describing nonlocal short-range correlations is used.

In recent years, the kinetic and hydrodynamic descriptions of transport phenomena have been improved significantly through the extension of the Boltzmann physical kinetics. In this review the basic results of the generalized Boltzmann kinetic theory of partially and fully ionized gases are presented and some of its applications are discussed.

Universal and nonuniversal critical exponents of a three-dimensional Ising system with weak quenched disorder are discussed. Experimental, computational, and theoretical results are reviewed. Particular attention is given to field-theoretical renormalization-group results. Different renormalization schemes are considered with emphasis on the analysis of the divergent series obtained.

The results of research into high-power, high-efficiency noble-gas-halide excilamps using glow, capacitive, and barrier discharges for the excitation sources are presented. The maximum radiation powers and minimum consumption are achieved with glow discharge lamps. An excilamp with an average radiation power of 1.6 kW on KrCl* molecules (λ = 222 nm) and 1.1 kW on XeCl* molecules (λ = 308 nm) is developed, whose energy conversion efficiency exceeds 10%. The use of an electrodeless capacitive discharge leads to sealed off excilamps with a simple emitter design, which have a power of 1 to 10 W and a service life of about 2500 h and more. Barrier-discharge excilamps possess both high energy parameters (> 100 W m⁻¹) and a long service life. Excilamps can find wide practical applications as new powerful sources of UV and VUV radiation.