On the level density of random band matrices

Translated from Matematicheskie Zametki, Vol. 50, No. 6, pp. 31–42, December, 1991.     

Interaction between large and small signals in a resonant transmission line based on magnetostatic waves

The influence of a large signal on the characteristics of a small signal near the frequency of the former is experimentally studied for the case of their simultaneous propagation through a resonant transmission line based on backward volume magnetostatic waves. The effects observed are caused by the excitation of spin waves in a ferromagnetic film at different large-signal frequencies and by the back influence of excited spin-wave packets on the amplitude and phase characteristics of the small signal.     

Trends in sorption preconcentration combined with noble metal determination.

Nowadays much attention is being paid to the determination of trace amounts of noble metals in geological, industrial, biological and environmental samples. The most promising techniques, such as inductively coupled plasma atomic emission spectrometry (ICP-AES), inductively coupled plasma mass spectrometry (ICP-MS) and electrothermal atomic absorption spectrometry (ETAAS) are characterized by high sensitivity. However, the accurate determination of trace noble metals has been limited by numerous interferences generated from the presence of matrix elements. To decrease, or eliminate, these interferences, the sorption preconcentration of noble metals is often used prior to their instrumental detection. A great number of hyphenated methods of noble metal determination using sorption preconcentration have been developed. This review describes the basic types of available sorbents, preconcentration procedures and preparations of the sorbent to the subsequent determination of noble metals. The specific features of instrumental techniques and examples of ETAAS, FAAS, ICP-AES, ICP-MS determinations after the sorption preconcentration of noble metals are considered. The references cited here were selected mostly from the period 1996 - 2006.     

A three-dimensional lattice gas approximation for multilayer adsorption

A three-dimensional lattice gas approximation for multilayer adsorbates is substantiated on the basis of statistical physics. In addition, some problems of equilibrium thermodynamics and kinetics are formulated, and a number of approximations are derived. A detailed kinetic theory of thin film growth, which is complementary to the applied approaches based on phenomenological models, thermodynamics of nonequilibrium processes, and solid medium and lattice gas models, is developed.Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 105, No. 1, pp. 130–148, October, 1995.     

Integration of differential forms on manifolds with locally-finite variations. II

In part I of the paper, we have defined n-dimensional C⁰-manifolds in ℝⁿ(m ≥ n) with locally-finite n-dimensional variations (a generalization of locally-rectifiable curves to dimensionn > 1) and integration of measurable differential n-forms over such manifolds. The main result of part II states that an n-dimensional manifold that is C¹-embedded into ℝ^m has locally-finite variations and the integral of a measurable differential n-form defined in part I can be calculated by the well-known formula. Bibliography: 5 titles. __________ Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 333, 2006, pp. 66–85.