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Alekseev V.V.,Russian Institute of Cooperation | Maksimov I.I.,Chuvash State Agricultural Academy
Eurasian Soil Science | Year: 2013

A new method for the rapid plotting of the soil water retention curve (SWRC) has been proposed that considers the soil water as an environment limited by the soil solid phase on one side and by the soil air on the other side. Both contact surfaces have surface energies, which play the main role in water retention. The use of an idealized soil model with consideration for the nonequilibrium thermodynamic laws and the aerodynamic similarity principles allows us to estimate the volumetric specific surface areas of soils and, using the proposed pedotransfer function (PTF), to plot the SWRC. The volumetric specific surface area of the solid phase, the porosity, and the specific free surface energy at the water-air interface are used as the SWRC parameters. Devices for measuring the parameters are briefly described. The differences between the proposed PTF and the experimental data have been analyzed using the statistical processing of the data. © 2013 Pleiades Publishing, Ltd. Source


Karpov S.V.,Chuvash State University | Kayukov Y.S.,Chuvash State University | Bardasov I.N.,Chuvash State University | Ershov O.V.,Chuvash State University | And 2 more authors.
Russian Journal of Organic Chemistry | Year: 2011

Reactions of 2-aroyl-1,1,3,3-tetracyanopropenides with thiols in acid medium led to the formation of the corresponding 2-alkylsulfanyl-substituted 2-(5-amino-2-aryl-4-cyano-2,3-dihydrofuran-3-ylidene)propanedinitriles. © 2011 Pleiades Publishing, Ltd. Source


Karpov S.V.,Chuvash State University | Kaukov Ya.S.,Chuvash State University | Grigor'ev A.A.,Chuvash State University | Nasakin O.E.,Chuvash State University | And 2 more authors.
Organic and Biomolecular Chemistry | Year: 2016

A novel fast, convenient and inexpensive synthesis of 1′,3′-dioxo-1′,3′-dihydrospiro[cyclopropane-1,2′-indene]-2,2,3,3-tetracarbonitrile and dimethyl 2,3-dicyano-1′,3′-dioxo-1′,3′-dihydrospiro[cyclopropane-1,2′-indene]-2,3-dicarboxylate is reported. These compounds undergo double carbanion cleavage under the action of alcohols resulting in the formation of stable salts, containing new allylic-type anions with potential application in organic electronics and as ionic liquid components. © The Royal Society of Chemistry 2016. Source


Kayukov Y.S.,Chuvash State University | Bardasov I.N.,Chuvash State University | Karpov S.V.,Chuvash State University | Ershov O.V.,Chuvash State University | And 3 more authors.
Russian Journal of Organic Chemistry | Year: 2012

Reaction of 2,2,3,3-tetracyanocyclopropyl ketones with water solution of sodium hydroxide after neutralization with sulfuric acid leads to the formation of 4-amino-1-hydroxy-3,6-dioxo-2,3,5,6-tetrahydro-1Hpyrrolo[3,4-c]pyridine-7- carbonitriles. Pivaloyltetracyanocyclopropane reacts in another way and is converted into sodium 6a-tert-butyl-3,4-dicyano-5-oxo-1,5,6,6a- tetrahydropyrrolo[2,3-b]pyrrol-2-olate. 1-Benzoyl-1-methylcyclopropane-2,2,3,3- tetracarbonitrile reacts with the sodium hydroxide with the retention of the threemembered ring and the formation of 11-methyl-4-phenyl-3,5,9- triazatetracyclo[5.3.1.01,7.04,11]undecane-2,6,8,10-tetraone. © 2012 Pleiades Publishing, Ltd. Source


Kayukov Ya.S.,Chuvash State University | Karpov S.V.,Chuvash State University | Bardasov I.N.,Chuvash State University | Ershov O.V.,Chuvash State University | And 3 more authors.
Russian Journal of Organic Chemistry | Year: 2012

Reactions of aliphatic 2,2,3,3-tetracyanocyclopropyl ketones with aqueous ammonia afforded 4-alkyl- 4-amino-2-oxo-3-azabicyclo[3.1.0]hexane-1,6,6- tricarbonitriles with conservation of the three-membered ring. Reactions of the same compounds with primary amines were accompanied by opening of the cyclopropane ring, and they led to the formation of 5-amino-6,6a-dimethyl-2-oxo- 1,2,6,6a-tetrahydropyrrolo[2,3-b]- pyrrole-3,4-dicarbonitriles as a result of successive heterocyclizations. © Pleiades Publishing, Ltd., 2012. Source

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