Homoleptic Poly(nitrato) Complexes of Group 14 Stable at Ambient Conditions

Using a novel approach in homoleptic nitrate chemistry, Sn(NO3)62− (3c) as well as the previously unknown hexanitrato complexes Si(NO3)62− (1c), Ge(NO3)62− (2c) were synthesized from the element tetranitrates as salt-like compounds which were isolated and characterized using 1H, 14N, and 29Si NMR and IR spectroscopies, elemental and thermal analyses, and single-crystal XRD. All hexanitrates are moderately air-sensitive at 298 K and possess greater thermal stability toward NO2 elimination than their charge-neutral tetranitrato congeners as solids and in solution. The complexes possess distorted octahedral coordination skeletons and adopt geometries that are highly symmetric (3c) or deformed (1c, 2c) depending on the degree of steric congestion of the ligand sphere. As opposed to the κ2O,O′ coordination mode reported for Sn(NO3)4 previously,1 all nitrato ligands of 3c coordinate in κ1O mode. Six geometric isomers of E(NO3)62− were identified as minima on the PES using DFT calculations at the B3LYP/6-311+G(d,p) level of which two were observed experimentally

Electroanalytical methods. Publications in 1999-2004

The scientometric study of publications on electrochemical methods of analysis (EMA) in a number of journals and proceedings of some conferences for 1999-2004 has been carried out. The contribution of papers on EMA to the total number of publications on analytical chemistry and the contribution of papers on individual methods (amperometry, voltammetry, including stripping and cyclic voltammetry, polarography, etc., potentiometry, including potentiometry with ion-selective electrodes, conductometry, coulometry, and other methods) to the total number of publications on EMA are estimated. Significant changes in the subject of publications, as well as in methodology and terminology, are noted over the period under review and compared to those over the earlier period. This is due to going from traditional studies to studies in the field of micro-and nanosized samples. The contributions of amperometry, electrochemiluminescence, chronoamperometry, chronopotentiometry, impedance measurements, spectroelectrochemical methods, and electrochemical microscopy have increased. It is noted that voltammetry and potentiometry are less used, but they are applied to the study of micro-and nanosized samples. In Russian publications, traditional trends of studies are retained. The contribution of publications on EMA to the total number of publications in analytical chemistry for 1946-2004 is estimated. It is ∼ 20% on the average in the last 25 years. © Nauka/Interperiodica 2006

History of voltammetry in Russia

The paper considers the evolution of electroanalytical methods in the former Soviet Union and Russia for more than 50 years, including the establishment of scientific research centers, the development of new methods, and the formation of scientific schools. The history of voltammetry (VA) can be conventionally subdivided into two periods, the history of polarography (from the late 1930s to 1981-1987) and the history of VA in different versions. The material is obtained from original publications, reviews, and proceedings of specialized conferences. The role of academicians V.I. Vernadsky and A.P. Vinogradov in the formation and development of VA in the former Soviet Union is noted. It is shown that the first work on polarography in the former Soviet Union was published by E.N. Varasova, a colleague of Vernadsky and a former student of J. Heyrovsky and the translator of his first monograph. The statistics of conferences on polarography and conferences on electrochemical methods of analysis is presented; the high scientific and experimental level of Russian research centers is demonstrated; and the role of the school of electrochemistry established by A.N. Frumkin is shown. © 2009 Pleiades Publishing, Ltd

ETEKOS experimental ecological system

The problem of changes in the ecology resulting, for example, in increases in water temperature because of discharges from large thermal power plants is considered. An experiment creating a model of such an ecological system is described

Industry choice by young entrepreneurs in different country settings: The role of human and financial capital

Entrepreneurial entry happens as a consequence of a general choice of an individual to become an entrepreneur. While most entrepreneurial entry studies rarely consider an entry into a particular industry to be an aspect of entrepreneurial decision making process, we address this issue taking into account individual, industrial, and country specific attributes. Using data from the Global University Entrepreneurial Spirit Students' Survey (2013-2014) on young and active entrepreneurs and extending it with objective indicators derived from World Bank, Global Entrepreneurship Monitor, and International Property Rights Index datasets, we investigate how various factors influence entrepreneurial industry choice on an aggregated level of industrial typology: knowledge-intensive and capital-intensive industries. Drawing on the RBV and contingency approach, we link an industry choice with the level of human capital development and an access to financial capital and test for possible country-specific moderation effects. Our findings indicate that both types of capital have a significant impact on industry choice by young nascent entrepreneur. Our results also suggest that specific country environment serves as a moderator in this relationship. Thus, our study contributes to entrepreneurial entry research stream extending the understanding of entrepreneurial entry decision making nuances relate to individual access to resources and both industry- and country-level contingencies.Research has been conducted with financial support from Russian Science Foundation grant (project No. 14-18-01093

Environmental controllers for carbon emission and concentration patterns in Siberian rivers during different seasons

Despite the importance of small and medium size rivers of Siberian boreal zone in greenhouse gases (GHG) emission, major knowledge gaps exist regarding its temporal variability and controlling mechanisms. Here we sampled 11 pristine rivers of the southern taiga biome (western Siberia Lowland, WSL), ranging in watershed area from 0.8 to 119,000 km2, to reveal temporal pattern and examine main environmental controllers of GHG emissions from the river water surfaces. Floating chamber measurements demonstrated that CO2 emissions from water surface decreased by 2 to 4-folds from spring to summer and autumn, were independent of the size of the watershed and stream order and did not exhibit sizable (>30 %, regardless of season) variations between day and night. The CH4 concentrations and fluxes increased in the order “spring ≤ summer 99.5 % CO2; <0.5 % CH4) from the watersheds of 11 rivers were equal to the total downstream C export in this part of the WSL. Based on correlations between environmental controllers (watershed land cover and the water column parameters), we hypothesize that the fluxes are largely driven by riverine mineralization of terrestrial dissolved and particulate OC, coupled with respiration at the river bottom and riparian sediments. It follows that, under climate warming scenario, most significant changes in GHG regimes of western Siberian rivers located in permafrost-free zone may occur due to changes in the riparian zone vegetation and water coverage of the floodplains