Photochemical synthesis of silver and gold nanoparticles in polyhydric alcohols

A procedure was developed for the synthesis of gold and silver nanoparticles in the presence of polyols like ethylene glycol, diethylene glycol, triethylene glycol, and 1,2-propylene glycol. Spectral characteristics of the obtained nanocomposites were mesured and kinetics of the formation of the colloidal phase was studied. The influence of the polyol nature and concentration on the photoinitiated formation of silver and gold nanoparticles was studied. The 1,2-propylene glycol is shown to exhibit maximal stabilizing effect.     

Determination of bis(2-ethylhexyl) phthalate in water by high-performance liquid chromatography with direct on-column preconcentration

A technique for the direct preconcentration of bis(2-ethylhexyl) phthalate (DEHP) on a reversedphase analytical column was proposed for the analysis of water samples by high-performance liquid chromatography (HPLC). A procedure for determining DEHP in surface-water and atmospheric precipitations in the laboratory and in the field was developed (the limit of detection is 0.1 Μg/L, the limit of determination is 0.3 Μg/L, and the relative standard deviation is 20 or 6% at a DEHP concentration of 0.3 or 10 Μg/L, respectively). The concentration levels of DEHP as a chemical tracer for the transfer and migration of air and water masses were examined in Lake Baikal water and in the snow cover of the Baikal region.     

Radiation—measurement complex of the Sirius synchrotron

The radiation-measurement complex associated with the Sirius synchrotron has been operating in the Scientific-Research Institute of Nuclear Physics of the S. M. Kirov Polytechnic Institute in Tomsk since 1985. Research on meson physics, channeling of high-energy electrons in crystals, new types of radiation, and applications of synchrotron radiation is carried out in this complex. The renovation of the synchrotron presently under way will allow these problems to be studied more effectively.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 5–7, June, 1991.     

Crystal structure of Rb-elpasolite Rb2NaAlF6

Single crystals of Rb₂NaAlF₆, the Rb analogue of the mineral elpasolite, are obtained in the NaF-Rb₂CO₃-Al₂O₃-Rb₃PO₄-H₂O system under hydrothermal conditions, and their structure is determined by X-ray diffraction (R = 0.0188): a = 8.3087(1) Å, space group $Fm\bar 3m$ , Z = 4, and ρ_calcd = 3.88 g/cm³. The hypothesis that Rb elpasolite exists in nature in late associations of pegmatites enriched in rubidium is proposed.     

Composite Copper-Based Coatings with Ultradispersed Phase

The electrolytic deposition of composite copper-based coatings with an ultradispersed phase(TiN or Al₂O₃) was studied. Conditions for obtaining coatings with the maximum microhardness were determined.     

A technique for assessment of the photocatalytic properties of plasmochemically synthesized crystalline TiO<Subscript>2</Subscript> nanopowders

The photocatalytic activity of crystalline titania nanopowders synthesized in a stream of ultrahigh-frequency discharge oxygen-containing low-temperature plasma was assessed. To this end, oxidation of an organic dye was carried out in UV-irradiated aqueous suspensions of TiO₂ at different concentrations and varied irradiation times.     

Crystal chemistry of KCuMn<Subscript>3</Subscript>(VO<Subscript>4</Subscript>)<Subscript>3</Subscript> in the context of detailed systematics of the alluaudite family

The crystal structure of new manganese potassium copper vanadate KCuMn₃(VO₄)₃, which was prepared by the hydrothermal synthesis in the K₂CO₃–CuO–MnCl₂–V₂O₅–H₂O system, was studied by X-ray diffraction (R = 0.0355): a = 12.396(1) Å, b = 12.944(1) Å, c = 6.9786(5) Å, β = 112.723(1)°, sp. gr. C2/c, Z = 4, ρ_calc = 3.938 g/cm³. A comparative analysis of the crystal-chemical features of the new representative of the alluaudite family and related structures of minerals and synthetic phosphates, arsenates, and vanadates of the general formula A(1)A(1)′A(1)″A(2)A(2)′M(1)M(2)₂(TO₄)₃ (where A are sites in the channels of the framework composed of MО₆ octahedra and TО₄ tetrahedra) was performed. A classification of these structures into subgroups according to the occupancy of A sites is suggested.