Voronezh State University

About: Voronezh State University is a education organization based out in Voronezh, Russia. It is known for research contribution in the topics: Silicon & Boundary value problem. The organization has 5166 authors who have published 6097 publications receiving 31680 citations. The organization is also known as: VSU & Voronezh University.

Influence of humidity on dielectric properties of nanocrystalline cellulose – triglycine sulfate composites

Abstract: Influence of the humidity on dielectric properties of composites nanocrystalline cellulose – triglycine sulfate in weak measuring field (1 V·cm−1) was investigated from room temperature to +120°C in the frequency range from 10−3 to 103 Hz. A comparative analysis of experimental results before and after heat treatment of samples was made. It was shown that before the heat treatment an additional peak at about +20°C in the temperature dependence of dielectric constant and a low-frequency maximum at 1.6 mHz in the frequency dependence of dielectric loss are observed. They are conditioned by the evaporation of water from the sample surface at the beginning of heating and the near–electrode polarization due to the accumulation of charge carriers at the electrode–composite layer respectively.

Dendroclimatology and historical climatology of Voronezh region, European Russia, since 1790s

Abstract: Existing high-resolution reconstructions of hydroclimate variability in Europe are lacking natural proxy data from European Russia. For this reason, developing new hydroclimate proxies for this vast region is crucial. It is even more important, because drought evidences from the forest-steppe region of European Russia will elucidate the eastern borders of large-scale meteorological events that had been covering large parts of Europe in the past. In this study, we provide new tree-ring chronologies of Pinus sylvestris L. for the site in the southernmost natural pine forest in European Russia. Based on these chronologies, we develop a quantitative drought reconstruction and disclose the driest years in the region since 1790s. The reconstruction of Standardized Precipitation Evapotranspiration Index explains 29–39% of instrumental period variability, it adequately tracks low-frequency (30–50 years) variations of drought indices as well as extreme events. Collection of historical evidences from periodicals of the 19th century and other historical evidences helped to verify the new reconstruction. Using gridded precipitation reconstruction over Europe, we showed a possible existence of large-scale hydroclimate events that had occurred in the East European forest-steppe region in the 19th century. Possible connections of drought events in European Russia with Atlantic Multidecadal Oscillation and Scandinavian teleconnection pattern are discussed. We argue that being a complex natural archive, ring width of pine in Voronezh region can be successfully used as an estimator of prolonged droughts (1–2 years).

Determination of acetone and ethanol vapors using semiconductor sensors

Abstract: Sensors with gas-sensing layers based on tin dioxide with nanosized catalytic additives of palladium, platinum, antimony, and lanthanum have been used to determine ethanol and acetone vapors in air. The use of nonstationary temperature modes, allowed us to reach record-breaking low detection limits for acetone (∼0.1 ppm). For the first time ethanol and acetone have been selectively determined with a single sensor.

Influence of Sodium Selenite on the mRNA Expression of the Mammalian Selenocysteine-Containing Protein Genes in Testicle and Prostate Cancer Cells

Abstract: The sodium selenite concentration that reduces the viability of Du-145 human prostate adenocarcinoma cells and F-9 mouse testicular teratocarcinoma cells was determined. We investigated the effect of sodium selenite on the mRNA expression level of the genes encoding mammalian selenocysteine-containing glutathione peroxidases and thioredoxin reductases (key antioxidant enzymes involved in the regulation of intracellular thiol redox balance), endoplasmic reticulum selenoproteins, and selenoproteins located in the testes and prostate.

Pyrazole-3(5)-diazonium salts in the synthesis of novel pyrazolo[5,1-c][1,2,4]triazines

Abstract: Coupling of pyrazole-3(5)-diazonium salts with cyclic 1,3-dicarbonyl (active methylene) compounds followed by cyclocondensation of the resulting hetarylhydrazones gave novel pyrazolo[5,1-c][1,2,4]triazines.