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Radical polymerization of unsaturated alkoxy-NNO-azoxy compounds was explored. Polymethoxy-NNO-azoxyethene, the first energetic polymer based on alkoxy-NNO-azoxy compounds, was obtained, and its major characteristics were studied. Thermodynamic calculations show that poly(methoxy-NNO-azoxyethene) may be of interest as a polymer component of active binders for solid composite rocket propellants.

Newly developed millennial δ13C larch tree-ring chronology from Siberia allows reconstruction of summer (July) vapor pressure deficit (VPD) changes in a temperature-limited environment. VPD increased recently, but does not yet exceed the maximum values reconstructed during the Medieval Warm Anomaly. The most humid conditions in the Siberian North were recorded in the Early Medieval Period and during the Little Ice Age. Increasing VPD under elevated air temperature affects the hydrology of these sensitive ecosystems by greater evapotranspiration rates. Further VPD increases will significantly affect Siberian forests most likely leading to drought and forest mortality even under additional access of thawed permafrost water. Adaptation strategies are needed for Siberian forest ecosystems to protect them in a warming world.

Currently, to determine the productive characteristics and diagnose the state of the bottomhole zone of wells (BHZ) operating the gas condensate deposits of the Beregovoye field, studies are being carried out, which include a set of interrelated methods that differ in theoretical basis, technology and execution technique. The purpose of these studies is to obtain information on the thermobaric parameters of the formation fluid in the reservoir, on the productive characteristics of wells, on the filtration-volumetric and mechanical properties of the porous medium. In this case, the curve of the derivative of the pressure drop at the bottom of the well with respect to the logarithm of time, built in two logarithmic axes, is widely used. To construct this diagnostic curve, three types of data are used: pressure recovery curve (HPC); pressure stabilization curve at constant well flow rate and studies with arbitrary change in flow rate and bottomhole pressure. Using the curve of the derivative of the pressure drop over the logarithm of time, a very wide range of possible structure of the wellbore area, the shape of its drainage boundaries, fractures, double media, etc., is diagnosed. When determining the productive characteristics during the development of the reservoir, the nature of the pressure change over the reservoir area was studied. The frequency of measurement of reservoir pressure by wells was established taking into account the geological features of the Beregovoye field and the rate of formation gas withdrawal from the reservoir.

Reservoir simulation models are utilized by oil and gas companies with a purpose to develop fields. Expansions and improvements in simulation software have lessened the time to develop a model. Simulating the reservoir aims to realize fluid flow, physical, and chemical procedures happening in a hydrocarbon reservoir adequately well for the reason of improving hydrocarbon recovery under various working stipulations. Grid-orientation effects are complicated problem in numerical reservoir simulation. These influences were coming when utilized of numerical utilization mechanism to conditions characterizing physically inconstant displacement procedure. These impacts happen in an assortment simulation of inappropriate and favourable mobility ratio displacements. The current study presents a building static and dynamic model and suggests a development plan for the reservoir under study and change the orientation of the grids to examine the effects of these changes on the values of oil production rate, water cut, pressure, cumulative oil production, and recovery factor. The case studies for an Iraqi oil field which is located in the South East of Iraq. Different values of recovery factors were obtained when the orientation of the grids had been changed.

In this work, four wells were analyzed at the Srednebotuobinskoye oil, gas and condensate field located in the Republic of Sakha (Yakutia). Production of oil reserves is complicated by the problem of gas breakthrough from the gas cap into the oil area of the reservoir, which leads to gasification of production wells up to their full shutdown. The field is characterized by the presence of a thin oil rim. That is why there is an urgent need to develop innovative technologies capable of ensuring higher oil recovery rates. The result of the conducted analysis is the object of implementation of the research results of this work.

The kinetic and molecular weight characteristics of the copolymers of n-butyl acrylate and styrene (95: 5 wt.%) obtained by the method of radical polymerization with reversible chain transfer were studied. The dependence of the refractive index on the molecular weight of the copolymers of n-butyl acrylate and styrene is shown.

The results of dating of extreme climatic events by damage to the anatomical structure and missing tree rings of the Siberian larch in the upper forest boundary of the Altai Republic are given. An analysis of the spatial distribution of the revealed dates over seven plots (Kokcy, Chind, Ak-ha, Jelo, Tute, Tara, and Sukor) allowed us to distinguish the extreme events on interregional (1700, 1783, 1788, 1812, 1814, 1884), regional (1724, 1775, 1784, 1835, 1840, 1847, 1850, 1852, 1854, 1869, 1871, 1910, 1917, 1927, 1938, 1958, 1961), and local (1702, 1736, 1751, 1785, 1842, 1843,1874, 1885, 1886, 1919, 2007, and 2009) scales. It was shown that the events of an interregional scale correspond with the dates of major volcanic eruptions (Grimsvotn, Lakagigar, Etna, Awu, Tambora, Soufriere St. Vinsent, Mayon, and Krakatau volcanos) and extreme climatic events, crop failures, lean years, etc., registered in historical sources.

This article examines the effect of additional blowing on performance indices and production costs for the production of steel in the converter shop at the Chelyabinsk Metallurgical Combine. It is shown that deviations from prescribed steelmaking practices in the shop, the use of pig iron with an unstable chemical composition and temperature, the lack of information on the pig iron for use by the shop supervisor before the beginning of heats, the cold-charging of scrap with a low bulk density, the use of poor-quality lime, and other problems make it impossible to conduct the blow with the optimum blowing, temperature, and slag regimes. This makes it necessary to take corrective actions: heats are subjected to additional blowings to attain the required temperature and necessary contents of C, S, and P. More than 90% of the heats at the combine require additional blowing “for temperature” and as much as 18% need additional blowing “for phosphorus and sulfur.” It was established that the unit consumption of metallic charge materials and steel production costs are respectively 19.60 kg/ton and 249.39 rubles/ton higher for heats which receive additional blowing.

Highly compact (99%) solid electrolyte Ce0.8Gd0.2O1.9 with submicron (0.3 μm) grains is synthesized. The dilatometric (20–850°C) and conductivity (180–350°C) measurements are performed on the electrolyte in air and as a function of the partial oxygen pressure $$p_{O_2 } $$ (0.21−1×10−25 atm) at 600, 700, and 800°C. An inflection is found in the temperature dependences of the thermal coefficient of linear expansion and conductivity (impedance measurements) at ∼230°C, which is the evidence for a phase transition. The activation energies for conduction in the grain bulk and boundaries differ only slightly, indicating that the grain boundaries’ resistance is caused not by the precipitation of the second phase at the boundaries, but most probably by the presence of intergranular nanopores. The dilatometric measurements confirm a significant increase in the linear dimensions of Ce0.8Gd0.2O1.9 in the reducing atmospheres with a parallel increase in its electron conductivity. The electron conductivity and specific elongation increase proportionally to $$p_{O_2 }^{ - 1/4} $$ at all temperatures. The $$p_{O_2 } $$ values, at which the transport numbers of ions t i = 0.5, are determined. They are 10−22.5, 10−20, and 10−18 atm at 600, 700, and 800°C, respectively.

A complex investigation of solid electrolytes Ce1−x Sm x O2−δ (x = 0.10−0.30) is performed in a broad temperature interval by methods of x-ray diffraction analysis, electroconduction, dilatometry, differential scanning calorimetry, and thermogravimetry. Ceramic technology is used for the synthesis. The density of the obtained specimens is no lower than 95%. The dilatometry measurements reveal the presence of singularities in the curves obtained at temperatures in the region of 180–230°C, which may be ascribed to a phase transition of the type order-disorder of hypothetical phase Ce7SmO15.5. The electroconduction and dilatometry methods also point to the presence of singularities in the temperature dependences in the temperature interval extending from 800 to 870°C.

The effect of the composition and density of ceramics on the electroconductivity of solid electrolytes Ce1 − xGdxO2 − δ(x = 0.09–0.31) with a submicron (0.1–0.3 µm) grain size, which are prepared from nanosized powders, is investigated. The powders are synthesized by two methods, specifically, by evaporation of a target with the aid of the radiation of a pulsed carbon dioxide laser and by a chemical method of burning. The samples of ceramics are prepared by magnetopulsed or quasi-isostatic (200–500 MPa) pressing and subsequent caking in air at a temperature of 1100–1300°C. It is established that the electroconductivity of the obtained solid electrolytes is higher and the effective activation energy for conduction is considerably lower as compared with analogous electrolytes with a micron grain size.

Investigations of phase transitions in barium cerate are carried out by methods of dilatometry and differential scanning calorimetry. Thermal desorption of gases and temperature dependences of electroconduction in dry and humid air are studied. Barium cerate exhibits complex polymorphism, undergoing a number of structural conversions at 300– 1300 K. The peaks in the spectra of thermal desorption of CO2 and H2O correlate with variations in the crystal lattice. Structural changes in BaCeO3 affect activation energies for the carrier transport and the shares of partial conductivities.

Direct measurements of heat balance (turbulent heat transfer and evaporation heat consumption) by the method of turbulent pulsations in 1998-2000 and 2002-2004 were used to obtain information on the daily, seasonal, and annual dynamics of energy fluxes and mass transfer between the atmosphere and the typical ecosystems of Siberia (middle-taiga pine forest and raised bog, true four-grass steppe, with the use of data for typical tundra) along the Yenisei meridian (90 degrees E).

The laser induced nonlinear polarization rotation effect in a solution of Glycine has been investigated. The experimental data on polarization rotation of the laser beam are presented and have been used to determine of the third- order molecular susceptibility for the process of interest.

Rubidium vapor (1011 - 1014 cm-3) was irradiated by a dye-laser beam (10 kW(DOT)cm-2 - 2 MW(DOT)cm-2, pulse duration approximately 30 nsec, linewidth

Statistical analysis of high-frequency variations in the radial dimensions of tracheids was carried out using precise measurements of five radial rows in each annual tree ring for several coniferous species: Larix gmelinii, L. leptolepis, L. sibirica, Picea abies, Pinus sylvestris, P. rigida, and P. densiflora. More than 25 tree rings with a varying number of cells and width were measured for each species. High-frequency variations in radial dimensions were found to have a regular (cyclic) characteristic and accumulated 5 to 11% of the total variability. The cyclic pattern was identified using Fourier analysis of time-related or successive series statistical procedure. The first order autocorrelations (-0.45 to -0.74) and the mean cycle of high-frequency variations (2.1-2.5) did not depend on the number of cells in the annual ring, i.e., they are determined by internal causes. The cyclic pattern of high-frequency variation in tracheid dimensions is used to interpret the seasonal mechanism of xylem formation. Specifically, (1) high-frequency variations in the tracheid radial size take place during the last asymmetrical division of the xylem mother cell before transition to the elongation zone, (2) the final tracheid radial size is mostly determined within the zone of division due to the last asymmetrical division, and (3) acceleration of cell cycle from the initial to the periphery of the cambial zone. The results obtained are also discussed with respect to the mechanisms of xylem differentiation.

Reasons and ecological impacts of damaged forests are analyzed. The main aspects of ecological stabilization and steady development of the forest complex are discussed. Alternatives for change of forest utilization structure as well as a reasonable course for improving logging technologies and wood processing are considered. The decision to adopt an ecosystem forest management will promote forest-complex stability.