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In the framework of the functional model of the influence of atmospheric parameters on the growth of conifers, it is shown how changes in the level of UV-B radiation, indirectly related to changes in stratospheric ozone, affect the density of annual rings. Phytohormones initiate tree adaptation mechanisms by regulating the growth rate of tree cells. The simulation results showed that there is a strong relationship between the rates of changes in density and total ozone content.

The response of the total ozone (TO) at subarctic latitudes to volcanic eruptions, products of which were injected into the stratosphere, is analyzed. It is established that the behavior of the series of average annual TO values according to the TOMS, SCIAMACHY, and GOME space equipment data averaged for 55°–65° N latitudes agrees with the activity of explosive volcanic eruptions. The series of the TO satellite monitoring instrumental data are extended by 200 years into the past using a reconstruction from the dendro-chronologic data. An analysis of the series of TO reconstructed values indicates that volcanogenic perturbations of the subarctic ozonosphere initiate long-term negative TO deviations. In this case, the TO negative deviation depth depends on the frequency of the ozonosphere volcanogenic perturbations and the phase of quasiperiodic oscillation cycles rather than on the strength of a single volcanic explosion.

This paper presents images of wood structure for various measurement regimes of X-ray microtomography. This is done by obtaining tomographic slices (iSee, CTvox), averaging them with the help of a statistical script called Adobe Photoshop, converting the average images into multidimensional data sets, and then averaging the image profiles (OriginCalc) to finally obtain a two-dimensional array of dendrochronological series of tree-ring density. The results of measurements are checked by a weight method to confirm the reliability of the data processing algorithm. For dendrochronological measurements of the ring density, it is shown that, depending on the width, two modes can be used: 80-µm (for wide rings) and 30-µm (for narrow rings). A measurement mode of less than 10-µm is used to display the structure of the wood inside a ring. The results of XCT-density measurements performed with an 8-µm resolution are given to assess the daily changes in wood density during the growing season.

A probabilistic-statistical parameterization of time series characterizing geological and climatic processes allows determining some regularities by an autocorrelation analysis of signals which differ in nature. The use of the autocorrelation method for analyzing data related to solar and tectonic activity and characterizing the level of stratospheric ozone (total ozone content), hydrothermal regimes (De Martonne aridity index), and wood structure (maximum density of annual rings) allows us to find regularities in time series of various natural processes. Data on the maximum density of Siberian larch trees growing in the Altai Mountains made it possible to calculate the past changes in total ozone content and the aridity index in the Altai Mountains from 1900 to 2014 based on some similarities in the series and a separation of a dendrochronological signal into its main components.

The paper presents the results of analysis of data of spatiotemporal variations of ozonosphere using modified Caterpillar method of main components (Saint Petersburg University). We use as the studied sample the TOMS satellite data of total ozone (TO) and data of TO reconstruction from annual ring density of coniferous trees for midlatitudes. We explored the possibility of approximation of TO time series based on simple components separated by this method.

Measurements have been made on the thermal conductivity and thermal diffusivity for corundum refractories based on hollow granules having apparent densities of 0.3–0.6 g/cm3, as well as foam corundum ones at about 0.5 g/cm3, which cover the range 200–1700°C. A conduction model has been devised that gives a qualitative explanation of the temperature and porosity effects.

Experimental data on the thermal conductivity of refractory fills based on MgO, Y2O3, ZrO2, and Al2O3 with different fraction composition were obtained. The limits of applicability of the model of thermal conductivity of granular systems for materials of this class were determined.

On a prepare un programme pour calculer sur ordinateur l'erreur de mesure de la conductivite et de la diffusivite thermique resultant de la distorsion du champ de temperature pour differentes methodes d'installation des transducteurs de temperature

This paper describes a method of measurement of the thermal diffusivity of refractory powders at temperatures of 400-2100 K in different gaseous media in the p = 10/sup 2/-10/sup 5/ Pa pressure range. The method developed is based on the rules of steady heating of cylindrical specimens. The calculation equation has a form characteristic of regular conditions of the second order in an infinite cylinder with corrections for the deviation from quasisteadiness and for the nonuniformity of the temperature field in the specimen. Thermal diffusivities of magnesite powder and PIT-1 yttrium oxide powder are shown in different gaseous media. The method developed possesses satisfactory accuracy and makes it possible to obtain information on the thermal divusivity and conductivity of refractory powders in a broad temperature range and in the area of high temperature.