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When studying the properties of candidate materials for fuel elements of designed nuclear power plants, the most important role is played by conducting reactor experiments. To obtain information about the temperature change of samples of experimental fuel rods in real time, they are instrumented with thermocouples. The correctness of the performed measurements depends on various factors, an important one of which is the quality of the thermocouple seal on the surface of the test sample. As part of the preparation for conducting fuel experiments at the IR-8 reactor of the National Research Center Kurchatov Institute, it is necessary to conduct pre-reactor tests of experimental fuel rods and their prototypes. This article discusses a computational and experimental method, the use of which makes it possible to obtain the inertia of thermocouples attached to the test object in various ways. Requirements for the inertia of thermocouples used during testing are determined on the basis of the parameters of the considered nonstationary processes. Comparison of the total inertias of the fixed thermocouples and the experimental prototype can also be used to draw conclusions about the quality of the embedment. To test the proposed method for determining inertia, a special laboratory rig was created on which experimental values were obtained for thermocouples attached to the surface of the sample in two ways. A description and results of testing an analytical model for determining the error in measuring the sample temperature using thermocouples are provided. The possibilities of using the developed computational and experimental method in preparing reactor research of experimental fuel rods are considered. [ABSTRACT FROM AUTHOR]

The effect of 10 at % Mn introduced into the classic FINEMET (Fe73.5Cu1Nb3Si13.5B9) at the expense of Fe on the magnetic properties, magnetic anisotropy, and structure, which are formed after nanocrystallizing annealing at 520°C for 10 min to 4 h in the presence of tensile stresses σ = 200 MPa and in the absence of them, is studied. It is shown that, for the Fe63.5Mn10Cu1Nb3Si13.5B9 alloy, like for the classic FINEMET, the annealing in the presence of tensile stresses results in inducing the transverse magnetic anisotropy; however, the constant of induced magnetic anisotropy decreases by 4 times. The coercive force of the Mn-containing alloy increases as the time of annealing both in the presence of tensile stresses and without them increases, whereas the coercive force of FINEMET is almost unchanged. It is shown that the Mn-containing alloy subjected to 10-min treatments already is characterized by the presence of the borides along with the α-Fe(Si, Mn) solid solution and Fe3Si phase. This leads to changing the ratio of volume fractions of structure constituents with the negative and positive magnetostriction, which is likely to cause the decrease in the induced magnetic anisotropy constant of the Mn-containing alloy. The average grain size in the Mn-containing alloy is shown to increase as the time of treatments increases; this fact, along with the formation of borides, leads to the increase in the coercive force. [ABSTRACT FROM AUTHOR]

The contribution of the morpho-physiological parameters of leaves and tubers of 22 potato varieties (Solanum tuberosum L.) to the formation of yield under conditions of insufficient soil moisture and high air temperatures is studied. Discriminant analysis found that the stomata size (12%), chlorophyll content (10%), number of tubers (29%), and average tuber weight (21%) determined the gradation of plants by yield. The specific surface density of leaves (38%), the content of chlorophyll (13%) and carotenoids (13%), and the leaf area (12%) made the greatest contribution to discrimination in relation to ecological plasticity. It is concluded that the number of stomata per unit area of the leaf, the specific surface density of the leaf, and the content of photosynthetic pigments are the key characteristics that contribute to both the high yield and the adaptive capacity of potatoes. [ABSTRACT FROM AUTHOR]

We studied phenocrysts and melt inclusions in order to evaluate physical and chemical conditions of petrogenesis of the Sulawesi Island (southwestern Pacific subduction belt) basalts. The compositions of the clinopyroxene and plagioclase phenocrysts hosted by basalts of the Lokon Volcano indicate two types of melts: primitive and differentiated. The primitive magmas produced high-anorthite plagioclases that are absent from the Lokon volcano andesites. The second type of melts produced clinopyroxenes and plagioclases of similar composition in basalts and andesites. Similarities in the compositions of homogeneous glasses of melt inclusions in minerals from the Lokon Volcano and other volcanoes of Sulawesi Island and the SW Pacific suggest similar P–T conditions for the formation of magmatic systems. In particular, inclusion data demonstrate that basaltic magmas of the Lokon and Soputan volcanoes are primitive melts (SiO2 = 48.2–51.5 wt % and MgO up to 8 wt %), which is consistent with the contents of other oxides. These inclusions plot at the beginning of the "andesitic" trends in variation diagrams. Accordingly, these melts could be the primary melts for the entire magmatic system that formed andesitic to basaltic effusive rocks of the Tondono caldera and the Lokon and Soputan volcanoes. Based on the compositions of melt inclusions and host minerals in Lokon basalts, we concluded that clinopyroxene phenocrysts crystallized at two levels: 20.6–14.5 km (1150–1130°С) and 13–6 km (1145–1105°С), and plagioclase phenocrysts crystallized at 1160–1120°С. In general, our data on melt inclusions and phenocrysts indicate fundamental differences in the PTX parameters of the magmatic systems that formed basalts and andesites of Sulawesi Island. The basalt-hosted clinopyroxene phenocrysts crystallized from compositionally stable melts at slightly decreasing temperatures and a significant pressure drop during magma ascent. In contrast, crystallization of phenocrysts in the andesites occurred with delays in deep intermediate chambers, at constant pressures and a significant drop in temperature, which facilitated the processes of fractionation and evolution of melts. [ABSTRACT FROM AUTHOR]

The aim of this research is to identify and recommend for production or practical breeding varieties and hybrid potato material of various genetic and geographical origin, combining high yield, field resistance to mosaic viruses, and adaptability to stressful abiotic environmental factors, as well as to optimize and improve the efficiency of field evaluation of potato varieties. The research was carried out in 2019–2021 in Bezenchuksky raion of Samara oblast. The year 2019 was characterized by a spring drought, while 2020 and 2021 by spring–summer droughts. The hydrothermal coefficients for these years were 0.45, 0.47, and 0.61, respectively. In conditions of high temperatures and insufficient moisture, 36 new and promising potato varieties of domestic selection were evaluated according to a complex of economically valuable characteristics. The standards for the corresponding maturity groups are the varieties of Gala (medium-early), Zhigulevskii (midseason), and Udacha (early-season). The experimental material was planted in four repetitions; the number of plants in each repetition was 50. The predecessor was spring wheat. The soil of the experimental site was terraced chernozem, ordinary, low-humus, medium-thick, heavy loamy. The increased yields in the medium-early group were obtained for the varieties Krasa Meshchery, Debut, and Sudarynya, which exceeded Gala standard by 9.9, 4.8, and 2.8 t/ha, respectively. The increased yields in the midseason varieties are Siverskii and Alaska (8.6 and 5.0 t/ha higher than Zhigulevskii standard, respectively), while the Terra variety was in the early-season group (5.0 t/ha above the standard Udacha). The same varieties have high levels of field virus resistance (seven to nine points) to the most harmful X and Y viruses in the conditions of the Middle Volga region. Three main components that have the most significant impact on the variability of the studied parameters have been identified. It is shown that field virus resistance is the main limiting factor of yield for the studied set of varieties under conditions of elevated air temperatures and insufficient humidification. The share of the first component accounted for 34.6% of the variation of signs. It includes, with maximum loads of –0.801, –0.640, and –0.604, the yield and resistance to potato viruses X, and S and M, respectively. [ABSTRACT FROM AUTHOR]

Twenty-four potato (Solanum tuberosum L.) varieties differing in ripening groups (early, middle-early, and mid-season-ripening) were studied. Potatoes were grown under the conditions of the Middle Volga region of Russia in 2019–2021. It was found statistically that the yield (t/ha) of the early and mid-season-ripening varieties was negatively correlated with the increase in average temperatures during the growing season from May to August (R = –0.97, p = 0.04). Soil moisture content at a depth of 20 cm was positively correlated with the yield of middle-early varieties (R = 0.97, p = 0.04). The average tuber weight in the early varieties was sensitive to the increase in average temperatures (R = –0.95, p = 0.04). An increase in soil moisture content was beneficial to the average tuber weight (R = 0.98, p = 0.04), though only in the middle-early and mid-season-ripening groups. However, the soil moisture content and the tuber numbers in the mid-season-ripening varieties were negatively correlated (R = –0.96, p = 0.05). [ABSTRACT FROM AUTHOR]

Using the pump-probe method, the short-lived induced and long-lived absorption capacity of a crystal violet (CV) dye is studied in various solvents. The solvents selected for this study are water, dimethyl sufoxide (DMSO), and isopropyl and ethyl alcohols. The formation of triplet-triplet states of CV is observed in these solvents under excitation by the 4-th harmonic nanosecond radiation of a Nd:YAG-laser (wavelength 266 nm, average power 25.5 mW, pulse repetition frequency 3 Hz, pulse duration 10 ns, and peak power 10−12 MW/cm2). It is shown that the nonstationary spectra of induced absorption of CV in ethanol contain two bands at 400 and 485 nm. In isopropyl alcohol, both singlet-singlet and long-lived triplet-triplet absorption of CV > 17.2 ns is recorded at room temperature in the region of 400–500 nm. [ABSTRACT FROM AUTHOR]

In the alloy Fe63.5Ni10Cu1Nb3Si13.5B9, which is conventional FINEMET with Fe replaced by 10 at % Ni, the effects of the temperature and time of nanocrystallizing annealing in the presence of tensile stresses (stress annealing, SA) on the magnetic properties, magnetic anisotropy, and structure are considered. In the entire studied SA temperature range (480–550°С), induced magnetic anisotropy (IMA) of the easy-plane type occurs in the studied alloy. The tensile stresses upon SA were 200 MPa. In the course of SA at the minimum temperature, anisotropy with the minimum IMA constant (200 J/m3) is induced. The maximum SA duration, i.e., 4 h, is required. At SA temperatures of 540–550°С, 10 min is sufficient to induce IMA with the maximum constant ~2000 J/m3. It is shown that the structural state (phase composition) is correlated with the magnetic properties and IMA. Thus, the increase in the coercivity with an increase in the SA duration at 540–550°С (as well as at 520°С) is due to the development of the tetragonal phase in the alloy. The α‑(Fe,Ni)Si solid solution and Fe3Si phases form upon treatment for 10 min. The decrease in the IMA constant with an increase in the SA time at 540–550°С from 10 min to 1 h is most likely due to the change in the volume fractions of the structural components of the alloy with negative and positive magnetostriction. [ABSTRACT FROM AUTHOR]

The quantum-chemical and spectroscopic methods make it possible to record the features of photoactivated processes occurring within and between molecules, as well as the structural rearrangements of molecules. To solve the fundamental problem of establishing a relationship between the photophysical and spectral-luminescent properties of organic molecules and their structure, a comparative analysis of the nature of electronically excited states and photoprocesses in coumarin and its related compounds (furocoumarin and 8-methoxypsoralen) has been carried out. To understand the mechanism of forming the absorption and fluorescence spectra of compounds, the schemes of electronically excited states of the molecules under study and the charge localization on the molecular orbitals have been calculated and analyzed. The investigated compounds are effective sensitizers, and the presence of the OCH3 group in the molecular structure has the strongest effect on the spectral-luminescent characteristics. This paper presents the results of studying the induced absorption spectra of 8-methoxypsoralen by the pumb-probe method with a delay of 30 ns in the range of 350–700 nm. The experimentally recorded induced absorption of 8-methoxypsoralen belongs to long-living photoproducts of a radical nature. [ABSTRACT FROM AUTHOR]

Rapidly quenched alloys of aluminum with cobalt and zirconium are investigated using a combination of means of physicochemical analysis to study the formation of finely dispersed structures that considerably enhance the strength characteristics of materials. Rapidly quenched alloys are studied, since it is a mode of alloy treatment that allows the maximum isolation of the strengthening phase. It is found that the transfer of the single-phase structure of a supersaturated solid solution of Alsupers(Co,Zr) to Als(Co,Zr) + ZrAl3 + Co2Al9 is accompanied by an increase in hardness, due to the sequential separation of the intermetallic phases in the finely dispersed state. It is shown that the value of the dispersion hardening effect depends largely on the temperature and time parameters of the decomposition of supersaturated solid solutions. [ABSTRACT FROM AUTHOR]

The structure of the Fe63.5Ni10Cu1Nb3Si13.5B9 alloy, which is a classic alloy of the FINEMET type with 10 at % Ni substituted for Fe, has been studied after crystallization in the presence of tensile stresses. It has been shown that, upon the crystallization of the alloy (520°C) both in the presence of a tensile load and without it, nanocrystals of an α-(Fe, Ni)Si solid solution and of the Fe3Si phase are formed with an increase in the duration of annealing from 10 min to 1 hour. When the length of the annealing is further increased from 1 to 4 hours, a tetragonal phase Fe3NiSi1.5 appears in the alloy. A relationship between the structural state (phase composition) of the Fe63.5Ni10Cu1Nb3Si13.5B9 alloy and its magnetic properties and the type of the induced magnetic anisotropy has been shown. The growth of the coercive force, which was previously observed in samples of this alloy as the duration of the annealing was increased to 4 hours, is therefore associated with the appearance of a tetragonal phase in the alloy. The transverse magnetic anisotropy, which is induced in the alloy in the process of nanocrystallizing annealing in the presence of a tensile load, is associated with the formation of nanocrystals of the α-(Fe, Ni)Si solid solution and of the Fe3Si phase with a negative magnetostriction. [ABSTRACT FROM AUTHOR]

A method and a scheme of obtaining a femtosecond pulse train without frequency comb offset and selectable carrier–envelope offset phase are proposed. [ABSTRACT FROM AUTHOR]

The effect of 10 at % Ni, which was introduced into the classic Finemet Fe73.5Cu1Nb3Si13.5B9 at the expense of the Fe content, on the magnetic properties of the composition has been considered. The alloy was subjected to nanocrystallizing annealing in the presence of tensile stresses and in their absence. It is shown that, similarly to the Ni-free alloy, in the Fe63.5Ni10Cu1Nb3Si13.5B9 alloy subjected to thermomechanical treatment, the magnetic anisotropy with the easy magnetization direction across the ribbon axis (transverse induced magnetic anisotropy) is induced. It was found that the 10 at % Ni addition almost does not affect the value of magnetic anisotropy constant induced under thermomechanical treatment and decelerates the process of magnetic anisotropy inducing at σ ≤ 200 MPa. The Ni-containing alloy subjected to nanocrystallizing annealing (at 520°C) in the presence of tensile stresses and in their absence demonstrates the more than 200-fold increase in the coercive force as the annealing time increases from 1 to 4 h, whereas the coercive force of the Ni-free alloy is almost unchanged. This is likely to be related to the appearance of new structural components in the Ni-alloyed composition upon annealing. [ABSTRACT FROM AUTHOR]

Abstract: The possibilities of improving the strength characteristics of alloys based on aluminum and niobium are studied. It is established that the use of scandium allows finely dispersed hardening intermetallide phases to be obtained. The maximum effect of dispersion hardening is observed upon annealing an alloy with the composition Al 99.0 at %, Nb 0.7 at %, and Sc 0.3 at % for 54 h at 300°С. [ABSTRACT FROM AUTHOR]

Abstract: Observed delays in the ground response to solar wind directional discontinuities have been explained as the result of larger than expected magnetosheath propagation times. Recently, Samsonov et al. (2017, https://doi.org/10.1002/2017GL075020) showed that the typical time for a southward interplanetary magnetic field (IMF) turning to propagate across the magnetosheath is 14 min. Here by using a combination of magnetohydrodynamic simulations, spacecraft observations, and analytic calculations, we study the dependence of the propagation time on solar wind parameters and near‐magnetopause cutoff speed. Increases in the solar wind speed result in greater magnetosheath plasma flow velocities, decreases in the magnetosheath thickness and, as a result, decreases in the propagation time. Increases in the IMF strength result in increases in the magnetosheath thickness and increases in the propagation time. Both magnetohydrodynamic simulations and observations suggest that propagation times are slightly smaller for northward IMF turnings. Magnetosheath flow deceleration must be taken into account when predicting the arrival times of solar wind structures at the dayside magnetopause. [ABSTRACT FROM AUTHOR]

For the purpose of developing materials with optimum magnetic properties for high-temperature applications (500-600°C), we have investigated the magnetic properties and structure of a nanocrystalline (FeCo)HfMoZrBCu alloy. The alloy was subjected to nanocrystallizing annealing (NA) at 620°C in the presence of an alternating magnetic field (magnetic heat treatment, MHT). The influence of the duration of the NA and of the amplitude value H of the ac magnetic field on the magnetic properties of the alloy and on their thermal stability has been studied. It has been established that the MHT carried out at 620°C is most efficient after holding in a magnetic field for 20 min. In this case, a decrease in the coercive force and an increase in the remanence have been observed. An increase in the time of the holding upon the MHT from 20 min to 4 h decreases the efficiency of the treatment. It has been shown that the MHT carried out at 620°C for 2 h and H = 9 kA/m leads to the smallest changes in the magnetic properties of the alloy after the subsequent holding at a temperature of 550°C for 30 h. However, this treatment does not ensure the thermal stability of the magnetic properties of the alloy at 550°C achieved earlier after the nanocrystallization of the alloy at 620°C for 20 min in the presence of tensile stresses (250 MPa). [ABSTRACT FROM AUTHOR]

Previous observations have shown a ∼10-15 min time delay in the ionospheric response to solar wind directional discontinuities marked by either southward or northward interplanetary magnetic field (IMF) turnings. We have studied one southward IMF turning observed by Time History of Events and Macroscale Interactions during Substorms (THEMIS) and GOES in the dayside magnetosphere. Using a global MHD model, we have reproduced the magnetopause motion in this event. We find that the observed delay in the ground response can be completely explained by deceleration of the directional discontinuity in the subsolar magnetosheath. We show that the speed of the discontinuity significantly decreases in the vicinity of the magnetopause where the magnetic barrier formed during the previous northward IMF interval. The southward turning can reach the magnetopause only after complete disruption of the magnetic barrier. The disruption or dissipation occurs via magnetosheath reconnection, as confirmed by high-speed jets in the magnetosheath. The magnetopause moves sunward as the directional discontinuity transits the magnetosheath. This sunward motion is followed by the earthward motion when the discontinuity strikes the magnetopause and magnetopause reconnection begins. [ABSTRACT FROM AUTHOR]

Background: Older adults with anxiety and/or depression experience additional memory dysfunction beyond that of the normal aging process. However, few studies have examined test bias in memory assessments due to anxiety and/or depressive symptoms. The current study investigated the influence of self-reported symptoms of anxiety and depression on the measurement equivalence of memory tests in older adults.Method: This is a secondary analysis of the Advanced Cognitive Training for Independent and Vital Elderly dataset, a randomized controlled trial of community-dwelling older adults. Baseline data were included in this study (n = 2802). Multiple indicators multiple causes modeling was employed to assess for measurement equivalence, differential item functioning (DIF), in memory tests.Results: The DIF was present for anxiety symptoms but not for depressive symptoms, such that higher anxiety placed older adults at a disadvantage on measures of memory performance. Analysis of DIF impact showed that compared with participants scoring in the bottom quartile of anxious symptoms, participants in the upper quartile exhibited memory performance scores that were 0.26 standard deviation lower.Conclusion: Anxious but not depressive symptoms introduce test bias into the measurement of memory in older adults. This indicates that memory models for research and clinical purposes should account for the direct relationship between anxiety symptoms and memory tests in addition to the true relationship between anxiety symptoms and memory construct. These findings support routine assessments of anxiety symptoms among older adults in settings in which cognitive testing is being conducted. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The Late Vendian (540-550 Ma) U-Pb zircon age of postcollisional granitoids in the Osinovka Massif was obtained for the first time. The Osinovka Massif is located in rocks of the island-arc complex of the Isakovka Terrane, in the northwestern part of the Sayany-Yenisei accretion belt. These events stand for the final stage of the Neoproterozoic history of the Yenisei Ridge, related to the completing accretion of the oceanic crust fragments and the beginning of the Caledonian orogenesis. The petrogeochemical composition and the Sm-Nd isotopic characteristics support the fact that the granitoid melt originated from a highly differentiated continental crust of the southwestern margin of the Siberian Craton. Hence, the granite-bearing Late Riphean island-arc complexes were thrust over the craton margin at a distance considerably exceeding the dimensions of the Osinovka Massif. [ABSTRACT FROM AUTHOR]

The interaction between elements in the transition zones of diffusion couples Mg + AgCd-alloy are studied. Isothermal sections of the Ag-Mg-Cd ternary system at 573 K are constructed. The existence of a Heusler phase based on H-AgMgCd compound is found in the field of the solid β′-solution. It is shown that the interdiffusion of components prevents the formation of ordered phases in the transition zones of bimetals, allowing us to determine the boundaries of second-type phase transitions in solid solutions. [ABSTRACT FROM AUTHOR]

Results from studying the effect zirconium has on solid-phase processes in aluminum-chromium alloys are presented. Rapidly quenched alloys are prepared via melt spinning. The quenching rate is ~10 K/s. By means of physicochemical analysis, it is shown that doping Al-Cr alloys with zirconium improves the thermal stability of supersaturated solid solutions and stabilizes their microcrystalline structure; this hinders the coagulation of intermetallic phases and thus improves the hardness of the alloys. It is found that supersaturated solid solutions of Cr and Zr in aluminum undergo stepwise decomposition; the temperature and time parameters of each step are shown in TTT diagrams. [ABSTRACT FROM AUTHOR]

Relative changes in the density, (d.d0)/d, of SiO2 glass in pressures up to 5·0 GPa were compared with the (d-d0)/d values of aluminosilicate and magnesium silicate glasses in the M2O(CaO)-Al2O3(MgO)-SiO2 system (M=Li, Na, K). It is shown that the silica glass is not the most highly compressible among the silicate glasses, as can be expected in the case of an ideal structure of SiO2 glass (the ideal structure of fused quartz is characterized by the absence of nonbridging oxygen atoms in the fully polymerized structural network, NBO/T≅0). The compressibility of silica glass is below that of aluminosilicate glasses with a high content of SiO2, such as KAlSi3O8 and NaAlSi3O8 glasses. This is related to the defect structure of SiO2 glass and the possible maintainance of abnormally high density of liquid silica in glass on cooling of the melt, due to its high viscosity. [ABSTRACT FROM AUTHOR]

The surfaces of the alloy based on ZrNi doped by silicon (3 at.%) in the amorphous and crystalline states and of the Zr and Ni foils were electrochemically modified for the first time. The modification was carried out in the ionic liquid in the galvanostatic regime. The much more uniform distribution of the nanosized fragments can be obtained and stability of their geometric shapes can be retained in the absence of intergrain boundaries and texture in the amorphous materials. [ABSTRACT FROM AUTHOR]

The effect of nanocrystallizing annealing in the presence of an ac magnetic field (magnetic heat treatment) and tensile stresses (thermomechanical treatment), as well as in the presence of both tensile stresses and an ac magnetic field (complex thermomechanical magnetic treatment) on the magnetic properties of the nanocrystalline (FeCo)HfMoZrBCu alloy and their thermal stability has been studied. It has been found that the nanocrystallization of the studied (FeCo)HfMoZrBCu alloy in the course of magnetic heat treatment, thermomechanical treatment, and thermomechanical magnetic treatment at low tensile stresses (6-30 MPa) leads to about a threefold decrease in the coercive force, but does not ensure the thermal stability of magnetic properties at high temperatures. In nanocrystallization, in the course of thermomechanical treatment at 620°С for 20 min under tensile stresses σ = 250 MPa has been found to be optimum for the high-temperature application (up to 550°С) of the studied alloy. [ABSTRACT FROM AUTHOR]

The thermal behavior of Na3H(SO4)2 is studied in the temperature range –180...220°C in a pre-vacuum. At 180°C, the compound decomposed into a mixture of phases: Na2SO4 (Cmcm), Na2SO4 (P63/mmc), Na2SO4 (Fddd), and Na2S2O7. The maximal thermal expansion was observed near the α33 axis. The anisotropy of thermal expansion sharply decreased together with the increase in temperature. [ABSTRACT FROM AUTHOR]

The thermal behavior of antiferromagnets FeBO3 and Fe3BO6 is investigated according to the low-temperature powder X-ray diffraction data. Unit cell parameters were refined by the Rietveld method. The coefficients of thermal expansion are calculated. The interrelation between the expansion and crystal structure is described. [ABSTRACT FROM AUTHOR]

The paper is devoted to the specifics in the chemical composition of synorogenic clay rocks in various environments: the Ural foredeep, Olyutorskii terrane, Dnestr pericratonic trough, Indus-Gang trough, etc. The compositions of the rocks are plotted in conventionally utilized discriminant paleotectonic diagrams. It is demonstrated that the bulk composition of such rocks, which were formed under active tectonic conditions typical of the collisional evolutionary phase of mobile belts, reflects the nature of the rock assemblages produced during both the divergent and the convergent (including collisional) phases. Their mean composition is the closest to PAAS as an integrated parameter of the average composition of the continental crust. The materials presented in the publication suggest that data on the bulk composition of clay rocks shown in conventionally utilized discriminant diagrams, such as SiO-KO/NaO, KO/NaO-SiO/AlO, are insufficient to reproduce the tectonic environments in which these rocks were formed. [ABSTRACT FROM AUTHOR]

The article presents study on age and pressure-temperature (P-T) parameters of metamorphism of metaterrigenous-carbonate deposits of the Derba Block in East Sayan, Russia. It mentions the Derba Formation includes graphite bearing calcite marble and graphite-micaceous quartzite. It adds the representation of granitoids by quartz diorite, biotite plagiogranite and microcline granite.

The effect of the temperature of nanocrystallizing annealing (NA) at temperatures of 670-750°C on the magnetic properties, structure, and thermal stability of the (FeCo)HfWMoZrBCu alloy has been studied. The NA was performed both in the presence of tensile stresses applied to samples and in the absence of stresses. It was found that the nanocrystallization of the alloy under applied tensile stresses induces the longitudinal magnetic anisotropy with an easy magnetization axis parallel to the long side of the ribbon. The optimum conditions for nanocrystallization of the alloy, which stabilize its magnetic properties at a fairly high temperature of 570°C, have been determined. [ABSTRACT FROM AUTHOR]

This article discusses the results of an investigation of the corrosion properties of fast-quenched and equilibrium alloys based on aluminum quenched with iron and vanadium. It has been demonstrated that the corrosion properties of the considered systems deteriorate with an increase of content of dopants, as well as with transition of alloys from a fast-quenched to equilibrium state. The observed effects are probably related to the deposition of new phases, which occur in an increase in content of dopant, as well as a result of thermal processing. The consequence of these processes is an increase in the total surface area of phase boundaries, which are the predominant locations of corrosion destructions. [ABSTRACT FROM AUTHOR]

It was established by a complex of physicochemical methods that are only phase based on the binary intermetallics ScAl and NbAl, containing neglible amount of doping additives, are found in in the system Al-Nb-Sc in equilibrium with aluminum. Aluminum and binary phases ScAl and NbAl come into eutectic equilibrium at 873 K. Joint doping of aluminum with niobium and scandium leads to a decrease in the extension of the range of a supersaturated solid solution based on aluminum. [ABSTRACT FROM AUTHOR]

Relative changes in the density (d-d0)/d of glasses in the CaO(Na2O)-Al2O3-SiO2 system, which characterise the compressibility of glasses, were compared with each other and compared with the values of their degree of depolymerization NBO/T. The results showed that, contrary to prevailing opinion, not all of the glasses with the ratio Al2O3/M(M2)O=1, containing Na+, have higher compressibility compared to that of similar glasses containing Ca2+. The compressibility of glasses agrees with the values of the degree of depolymerisation which were calculated considering oxygen triclusters, nonbridging oxygen atoms and highly coordinated aluminium. Aluminosilicate glasses follow the general dependence of the relative change in density on the degree of depolymerisation. [ABSTRACT FROM AUTHOR]

The phase equilibria in the Al-Ni-Cu-Zr quaternary system at 1123 K and a concentration of Zr higher than 30 at % have been determined using the methods of X-ray phase analysis, X-ray spectral microanalysis, scanning electron microscopy, and differential scanning calorimetry. An area of the existence of a quaternary liquid phase with a melting point of 1110 K at the concentrations of copper and zirconium equal to 15.1 and 58.0 at %, respectively, was detected in the system. The concentrations of other components vary in the range from 13.4 to 19.5 for Al and from 7.4 to 13.5 at % for Ni. For the first time, the existence of seven four-phase equilibria was determined experimentally. [ABSTRACT FROM AUTHOR]

Crystallization processes in the aluminum-rich region of the ternary Al-Cr-Zr system were studied via the complex of the methods of physical and chemical analysis. It was found that in the equilibrium crystallization of these alloys along the Cr: Zr = 14: 5 section, aluminum and the CrAl intermetallic compound are crystallized, whereas under non-equilibrium conditions at quenching rates of 10 degree s, ZrAl phase and aluminum-based supersaturated solid solution are formed. [ABSTRACT FROM AUTHOR]

The formation of an auroral bulge with a bright dynamical arc at its polar boundary is one of the main manifestations of the magnetospheric substorm expansion phase at the ionospheric level. At the same time, the region of discrete aurora broadens not only polewards but equatorwards as well. The discrete forms of auroras moving equatorwards form a dynamical equatorial boundary of the auroral bulge shifting together with them. The paper presents a spatial-time comparison of the drifting discrete auroras to the injection of energetic particles at the geostationary orbit. It is shown that bursts in the fluxes of energetic particles at the LANL geostationary satellites located in the same sector of MLT correspond to the majority of drifting discrete auroral structures observed by the all-sky camera. In the cases when the bursts in the fluxes are absent, the minimum latitude reached by the auroral structures at the equatorward drift is higher than the ionospheric projection of the geostationary orbit. A possible relation of the drifting discrete auroras to the plasma stream jets in the plasma sheet is discussed. [ABSTRACT FROM AUTHOR]

The effect of magnitude of tensile stresses (σ) applied to the (FeCo)HfWMoZrBCu alloy with refractory-metal additions during its nanocrystallization at 620°C for 20 min on the magnetic properties, structure, and thermal stability of the alloy is studied. It has been found that, during the nanocrystallization of the alloy under the effect of tensile stresses of 6-250 MPa, longitudinal magnetic anisotropy with an easy magnetization axis parallel to the long size of ribbon is induced in the alloy. The thermal stability of magnetic properties of the alloy under study has been shown to be determined by the thermal stability of induced magnetic anisotropy and to depend on the magnitude of tensile stresses applied during nanocrystallizing annealing (NA). The better thermal stability of magnetic properties has been observed for the alloy subjected to NA at σ = 170 MPa. After annealing at 570°C for 25 h, the magnetic properties of the alloy are unchanged. [ABSTRACT FROM AUTHOR]

The article discusses the first data gathered on the neoproterozoic granitoid magmatism found in Siberian craton's Sayan marginal uplift, a large structural element that spreads in the northwesterly direction from Lake Baikal to the basin of the Agul and Tumanshet rivers. It notes that the uplift's structures include the Buryusa and Sharyzhalgai superterranes that are connected to the Uriksko-Tumanshet collisional zone that contains widely abundant postcollision granitoid magmatism. It presents an exception by orphyry granodiorite of the Chernoziminskii Complex intruding coarse-clastic terrigenous rocks of the Ermosokhinskaya Suite that are deposited in the rift depression.

Nanocrystalline alloys (FeCo)HfBCu and (FeCo)HfBCu have been investigated to obtain materials with improved thermal stability and new features. In order to make the alloys produced by melt quenching on a rotating wheel nanocrystalline, they have been subjected to heat (HT) and thermomechanical (TMechT) treatments. The effect of HT and TMechT conditions on the magnetic properties, thermal stability, and structure of the alloys has been studied. The optimal HT conditions for obtaining the minimum values of the coercive force ( H) in the alloys have been determined. It is shown that TMechT of the alloys leads to the induced longitudinal magnetic anisotropy with the axis of easy magnetization along the long side of the ribbon in the studied temperature range of 520-620°C. It has been established that the alloys (FeCo)HfBCu and (FeCo)HfBCu are thermally unstable at temperatures above 500°C. [ABSTRACT FROM AUTHOR]

The alloy (FeCo)HfMoZrBCu is studied to obtain materials with improved thermal stability. The effect of the nanocrystallization conditions that occur during heat treatment (HT) and thermomechanical treatment (TMechT) in air at temperatures of 520-620°C on the structure of the alloy, as well as its magnetic properties and their thermal stability, is considered. Longitudinal magnetic anisotropy is shown to be induced in the alloy in the course of TMechT; the easy magnetization axis of the anisotropy is parallel to the long side of the ribbon. The alloy specimens subjected to heat and thermomechanical treatment have different magnetic characteristics. The (FeCo)HfMoZrBCu alloy is found to surpass the (FeCo)HfBCu and (FeCo)HfBCu alloys studied in [1] in the thermal stability of the magnetic properties. The magnetic properties of the alloy after nanocrystallization, which occurs in the course of TMechT (σ = 250 MPa) at 620°C for 20 min, hardly change during annealing at 550°C for 26 h. [ABSTRACT FROM AUTHOR]

Phase equilibria in ternary Al-Ni-Zr system have been studied using X-ray phase and electron probe microanalyses at 1123 K in the content range of 0-45 at % Al. A fragment of the isothermal section of this system has been plotted. The existence of three-phase equilibria ZrNi + ZrNi + ZrNi, τ-ZrNiAl + NiAl + ZrNi, NiAl + NiAl + ZrNi, ZrNi + ZrNi + τ-ZrNiAl at 1123 K has been established for the first time. Phase based of binary compound ZrNi dissolves up to 13 at % aluminum. The crystalline structure of the τ-ZrNiAl phase has been determined, including structure type USi, spatial group P4/ mbm ( a = 7.1852(7) Å, c = 3.3019(5) Å). [ABSTRACT FROM AUTHOR]

The paper reports data on metapelites (gneisses and crystalline schists) from various Early Precambrian lithostratigraphic units of the Yenisei Range (Kan and Yenisei complexes, Garevka Unit, and Teya Group). A representative selection of 57 samples from the examined vertical section were analyzed for major oxides, LILE, transition elements, HFSE, REE, radioactive elements, and other trace and minor elements. The most important distinctive geochemical feature of metapelites composing most of the vertical section is their elevated concentrations of Al, which are higher than in the Post-Archean Australian Shale (PAAS), K, Rb, Ba, Ga, Sc, Pb, Th, Nb, Y, and REE. These data and the systematics of elements in certain discriminant diagrams testify that the metasedimentary complexes in the sedimentation basin and the rocks associations composing the erosion area (crystalline massifs of the ancient basement of the Siberian craton) were strongly geochemically differentiated and mature. The composition of the eroded crustal material was close to the average composition of the post-Archean continental crust and PAAS. The metapelites of the Kuzeeva Unit in the Kan Complex and Penchenginskaya Formation in the Teya Group were the only ones that could have basic rocks as an additional source of material, as also follows from the elevated Cr concentrations of the rocks and their REE systematics. The three types of REE patterns of the metapelites largely correspond to the composition of the rocks that composed the ancient drainage areas and the degrees of the differentiation and averaging of their terrigenous material. The first predominant type corresponds to PAAS and the averaged composition of the upper continental crust. The second and third types of the REE patterns with high and low La/Yb ratios, respectively, and with or without negative Eu anomalies provide evidence of the contribution of tonalite-trondhjemite-granodiorite (TTG) or basite sources typical of granite-greenstone provinces. In certain diagrams, the compositional fields of Early Precambrian metapelites in the Yenisei Range almost exactly coincide with the compositional fields of regional fine-grained Riphean terrigenous rocks. This suggests that the Late Precambrian sedimentary rock sequences inherited their geochemical features from more ancient rocks. The reproduced ancient geodynamic environments in which the Early Precambrian metaterrigenous complexes of the Yenisei Range were accumulated correspond to ensialic continental marginal basins. The rocks of the Kan and Yenisei complexes and the Garevka Unit were formed mostly on active continental margins and, less frequently, on passive margins. The protoliths of metasedimentary rocks of the Teya Group were accumulated in a subplatform environment at a passive margin. [ABSTRACT FROM AUTHOR]

The article presents information a study related to the problems of the early stages of evolution of the crust in the Central Asian mobile belt. It informs that the processes are indicated by intraplate and riftogenic complexes widely abundant in the Late Neoproterozoic structures of the Yenisei Ridge which includes the problem of stratigraphic position of volcanic products and host sedimentary series. It further informs that the Neoproterozoic volcanogenic-sedimentary series occupied a higher stratigraphic level and had a different tectonic position.

X-ray diffraction and electron probe microanalysis were used to investigate phase equilibria in the ternary Cu-Al-Zr system at 1073 K in the Zr-rich region. The fragment of the isothermal section of the system was plotted. The regions of homogeneity of the ternary ZrCuAl and ZrCuAl phases were investigated. The type of phase equilibria between binary and ternary compounds of the Al-Cu-Zr system was established. It was found out that, at a Zr concentration above 55 at %, ternary compounds are not formed, and the ZrAl and ZrCu phases were in equilibria with α-Zr at 1073 K. [ABSTRACT FROM AUTHOR]