A Positive Doubly Power Bounded Operator with a Nonpositive Inverse Exists on any Infinite-dimensional AL-Space

In this paper we construct a positive doubly power bounded operator with a nonpositive inverse on an AL-space.     

A characterization of an order ideal in Riesz spaces

In this paper we give a characterization of order ideals in Riesz spaces.

     

Tetrabutylammonium Salts of Ruthenium(II) Nitroso Complexes

The paper describes synthesis of (nBu₄N)₂[RuNOCl₅](I), (nBu₄N)₂[RuNOCl₄OH](II), (nBu₄N)₂×[RuNOCl₄OH]·6H₂O (III), and (nBu₄N)₂[RuNOCl₅]· 2(nBu₄N)₂[RuNOCl₄(H₂O)]·2H₂O (IV). The complexes were studied by IR spectroscopy and powder Xray and crystal Xray analyses. The structures are built up of [RuNOCl₅]^2- (I, IV), [RuNOCl₄OH]^2- (II, III), and [RuNOCl₄(H₂O)]^- (IV) complex anions, (nBu₄N)⁺ cations, and crystal water molecules (III, IV). The substances are moderately soluble in water; highly soluble in polar organic solvents, such as acetone, ethanol, chloroform, methylene chloride; and almost insoluble in carbon tetrachloride and toluene. Under storage in light, the compounds decompose from the surface; in darkness I and II are stable, whereas III and IV can lose part of the crystal water.     

Forms of Rh(III) in Nitric Acid Solutions

The forms of Rh(III) in nitric acid solutions are studied by ¹⁴N, ¹⁵N, ¹⁷O, and ¹⁰³Rh NMR and electronic absorption spectra. At HNO₃concentrations below 5 mol/l, rhodium mainly exists as low-nuclear oligomers with a bridging fragment Rh(-OH)(-ONO₂)Rh; terminal positions of the central atoms are occupied by water molecules. It was found that the isotopic equilibrium ¹⁴NO^– ₃/¹⁵NO^– ₃of the bridging ligand sets in at an abnormally high rate, at which the isotopic exchange H₂ ¹⁷O/H₂ ¹⁶O of the terminal ligands also occurs in the dimers and trimers. The formation of low-nuclear oligomers is a common feature of Rh(III) complexes in aqueous solutions with ligand deficiency in the system. The possibility of isolating rhodium from nitric acid solutions using different methods is predicted.     

Synthesis of tri- and tetracyclosiloxanes with functional groups attached to the silicon atoms

Russian Chemical Bulletin -     

Some Conditions for a C0-Semigroup to Be Asymptotically Finite-Dimensional

We study the class of bounded C ₀-semigroups T=(T _t ) _t0 on a Banach space X satisfying the asymptotic finite dimensionality condition: codim X ₀(T)<, where X ₀(T):={x X:lim_t T _t x=0}. We prove a theorem which provides some necessary and sufficient conditions for asymptotic finite dimensionality.