Complexation with Metal Chelates at the Phase Interface in Gas Chromatography

A review of studies on the use of the chelate complexes as adsorbents and stationary liquid phases in gas chromatography is made. Data on the processes of complex formation at the phase interface and on the target production of the chelate-containing sorbents with preset properties are generalized. Practical application of the chelate-containing chromatographic packings for analytical separation and sorption concentration of organic substances is considered.     

Correlation characteristics of waves in lossy media with smooth fluctuations of the refractive index with oblique incidence on boundary

The features of coherence function (and angular spectrum) and also the fluctuation of amplitude and phase of wavefield in a random strongly absorptive medium are investigated in the case of arbitrary angle of incidence at the surface.

In this paper it is elucidated that with oblique incidence a dissipation in the random medium can accelerate the accumulation of wave fluctuations and its incoherence. This effect strongly depends on the rate of decrease of the 'wings' of the scattering indicatrix. An analytical theory (Rytov's approximation and modified method of parabolic equation) has been modelled by Monte Carlo simulation of wave propagation, and also by numerical solution of the model transfer equation. It is revealed that the width of an angle spectrum can nonmonotonically change with the immersion to the absorptive medium.     

Statistical characteristics of waves in random media with space-time inhomogeneities (review)

Conclusion Having presented the results one can note that, in recent years, the nonquasistatic theory of waves in media with parameters which fluctuate in space and time has achieved definite results. The effect of various factors on the spectral, energetic and polarization characteristics of waves has been clarified. At the same time, a number of problems remain insufficiently explained. For example, in the works cited above, the attention has been focused mainly on the analysis of correlation functions of a complex field. Other correlation functions (of phase, frequency, etc.) which are also of interest, have not been studied a great deal. The problem of strong fluctuations under a longitudinal propagation if slow waves in flows has not been completely clarified. The role of nonquasistaticity of fluctuations for higher-order moments (in particular, intensity fluctuations) has not been studied. Finally, for applications to realistic situations, it would be desirable to generalize the theory to the case of signals which are initially nonmonochromatic, to the case of statistically nonstationary media and, in addition, to active and nonlinear media.Gorkii State University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 30, No. 1, pp. 3–35, January, 1987.     

Synthesis of caprolactamates of group II metals

Caproiactamates of alkaline-earth metals and magnesium of the general formula , where M = Mg, Ca, Sr, and Ba, were synthesized from alkoxides, hydrides, and organometallic compounds of these metals and -caprolactam. The catalytic activities of caprolactamates obtained under conditions of anionic polymerization of -caprolactam were compared. It was demonstrated that the purest caprolactamates and, hence, the most effective catalysts of anionic polymerization of lactams can be obtained from organometallic and hydride compounds of these metals. The reactivities of alkoxides of the alkaline-earth metals and magnesium increase in metallation reactions of -caprolactam in the order Mg < Ca < Sr < Ba.Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2272–2275, November, 1995.The work was supported by the Russian Foundation for Basic Research (Project No. 93-03-4252).     

Spin Frustration and Competing Magnetic Exchange Interactions in Polynuclear Complexes of 3d Metals

Published examples of the use of the term "spin frustration" (SF) to describe the magnetochemical behavior of polynuclear complexes are examined critically. The difference between topological and real SF is demonstrated. A precise definition of SF in which SF only arises with degeneracy of the ground state of the complex with the presence of topological SF as an essential condition is proposed. The change of the energy levels forming the ground state of tri- and tetranuclear complexes of transition metals was analyzed in relation to the values of the exchange parameters. It was shown that not every degenerate ground state corresponds to spin frustration.