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Krasilin A.A.,St Petersburg Technological Institute Technical University | Almjasheva O.V.,RAS Institute of Macromolecular Compounds | Gusarov V.V.,RAS Ioffe Physical - Technical Institute
Inorganic Materials | Year: 2011

We have studied the effect of the structure of precursors on the formation of Mg 3Si 2O 5(OH) 4 nanotubes under hydrothermal conditions. The results demonstrate that a chemical match between the components of a starting mixture has an advantageous effect on the synthesis of nanotubular magnesium hydrosilicate and the morphology of the hydrothermal treatment products. © 2011 Pleiades Publishing, Ltd.


Pevzner L.M.,St Petersburg Technological Institute Technical University
Russian Journal of General Chemistry | Year: 2013

Alkyl cyanofurylmethanephosphonates are formylated with ethyl formate in the presence of sodium foil to form sodium derivatives of phosphonoacetic aldehyde. If phosphonoacetic aldehyde and nitrile groups occupy remote positions in the furan ring, the sodium derivative in DMSO solution exists in the form of carbanion carrying charge on the carbon atom adjacent to the aldehyde group. If the substituents are located at the adjacent carbons of furan ring, the solution equilibrium between the carbanionic (major product) and Z-enolate forms of salts is established. Alkylation of the formed salts with methyl iodide occurs exclusively at the oxygen atom to give methyl enolates. In most cases, a mixture of E-and Z-isomers is formed, the E one being prevailing. In the case of 2,5-location of the substituents in furan ring, the sodium salt is inactive, and the alkylation does not occur. © 2013 Pleiades Publishing, Ltd.


Pokonova Yu.V.,St Petersburg Technological Institute Technical University
Solid Fuel Chemistry | Year: 2011

A phosphoric acid cation exchanger having an exchange capacity of 3.5 mg-equiv/g and a mechanical strength of 95% was prepared based on a graft copolymer of asphaltite and styrene using chloromethylation and then phosphorylation reactions. A number of metal chloride catalysts and the reaction kinetics of phosphorylation were studied. It was found that the resulting phosphoric acid cation exchangers are more stable than analogous commercial materials. © Allerton Press, Inc., 2011.


Pokonova Yu.V.,St Petersburg Technological Institute Technical University
Solid Fuel Chemistry | Year: 2011

Radiation-resistant cation exchangers with a static exchange capacity to 5.91 mg-equiv/g and a mechanical strength to 95% were prepared based on a grafted copolymer of asphaltite and acrylonitrile. The adsorbents prepared in accordance with an industrial process using a charge mixture containing the copolymer exhibited higher sorption properties, as compared with those of the commercial adsorbent SKT, in the sorption of silver from multicomponent polymetallic solutions. The selectivity factor for silver was 3.55, as compared with 1.85 for SKT. © 2011 Allerton Press, Inc.


Pokonova Yu.V.,St Petersburg Technological Institute Technical University
Solid Fuel Chemistry | Year: 2011

The chloromethylation reaction of an asphaltite and styrene graft copolymer followed by the amination of the chloromethylated products was optimized. New strongly basic anion exchangers with an exchange capacity of 2.5 mg-equiv/g and a mechanical strength of 93% were prepared. © Allerton Press, Inc. 2011.


Pokonova Yu.V.,St Petersburg Technological Institute Technical University
Solid Fuel Chemistry | Year: 2011

The study of the kinetics of structurization of filled compositions demonstrated that a gel effect in the polycondensation-filled compositions occurs 8-12 min after the introduction of a hardening agent. Filling agents play a leading role in the process of structurization. © Allerton Press, Inc., 2011.


Bogdanov S.P.,St Petersburg Technological Institute Technical University
Glass Physics and Chemistry | Year: 2013

The article represents the possibilities of the iodine-transport method as a technique for intensifying the chemical reaction between solid-phase reagents. The prospects are shown for a decrease in the temperature and an increase in the rates of reactions like the synthesis of compounds from elements and the reduction of oxides using the iodide transport. © 2013 Pleiades Publishing, Ltd.


Bogdanov S.P.,St Petersburg Technological Institute Technical University
Glass Physics and Chemistry | Year: 2013

The paper is devoted to investigating the formation of solid solutions of metals from elements by the iodine-transport method. The possibility for the synthesis of a continuous series of solutions of Cu-Ni, as well as solutions of aluminum and silicon in copper, without the formation of liquid metallic phases is shown. © 2013 Pleiades Publishing, Ltd.


Ezhovskii Yu.K.,St Petersburg Technological Institute Technical University
Russian Microelectronics | Year: 2014

The results of investigations of processes for the formation of nanolayers of tantalum and aluminum oxides and multilayer compositions obtained by molecular layering onto silicon (100) and aluminum surfaces are presented. The conditions of the layer-by-layer growth of oxide structures and low-dimensional multilayer systems with alternating regions of the mentioned oxides are determined. The dielectric parameters of the synthesized nanostructures are evaluated. © 2014 Pleiades Publishing, Ltd.


Pokonova Y.V.,St Petersburg Technological Institute Technical University
Solid Fuel Chemistry | Year: 2010

Polymer materials with cohesion strengths from 2.9 to 5.4 MPa and adhesion to steel 3 from 2.6 to 3.1 MPa were prepared based on compositions of shale phenols. The specific elongation varied from 75 to 125%. In the use of compositions for the immobilization of industrial wastes, the leachability of strontium and cesium was 1 × 10-10 and 1 × 10 -12 cm2/s, respectively, whereas the leachability of cobalt and ruthenium was 1 × 10-13 cm2/s, which is several orders of magnitude lower than the leachability of 1 × 10 -8 cm2/s from Portland cement. © 2010 Allerton Press, Inc.

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