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AbstractIn this paper, the authors synthesize and study the phase formation of yttrium–iron garnet (YIG) using the supercritical antisolvent precipitation technique (SAS) at the initial stage for the first time. The effect of supercritical CO2 on the solution of acetates in the quasi-equilibrium state causes an abnormally high mobility of the structure’s elements. As a result, it becomes possible to form the equilibrium phase of the YIG solid product directly (without the appearance of transition oxides) at temperatures much lower than by solid-phase synthesis. The temperature decrease is due to a significant decrease in the activation energy of the solid solution.

The influence of cobalt additives on the phase composition, structural parameters, and morphology of indium oxide containing a mixture of crystalline phases is studied. The hydrothermal synthesis method is used to obtain the corresponding systems. It is shown that during the hydrothermal reaction, a mixture of phases of indium hydroxide and oxyhydroxide is formed, which, in turn, after thermal decomposition, transform into cubic and rhombohedral indium oxide, respectively. Depending on the concentration of the introduced cobalt, the ratio between the phases changes. At a concentration of 0.05 at % Co, the cubic phase is prevalent, while at an introduction of 0.25 at %, the rhombohedral phase is prevalent compared to the undoped sample. An increase in the concentration of cobalt leads to a decrease in the particle size, as well as an increase in the specific surface area and porosity of the composites. At the same time, the introduction of cobalt does not significantly affect the morphology of the resulting systems.

The microstructure and thermoelectric properties of materials based on p-type Bi0.5Sb1.5Te3 and n-type Bi2Te2.4Se0.6 solid solutions doped with graphene are studied. The samples are obtained by spark plasma sintering of powders prepared by melt spinning and crushed in a ball mill together with graphene plates, which are introduced in an amount of 0.05, 0.1, and 0.15 wt %. Scanning electron microscopy is used to study the composition and microstructure. The samples with p-type conductivity have a fine-grained (on the order of hundreds of nanometers) structure with microsized tellurium-based eutectic inclusions. The samples with n-type conductivity contain grains with melted edges. The thermoelectric parameters are measured: Seebeck coefficient, electrical conductivity, thermal conductivity at room temperature and in the temperature range from 100 to 700 K; and the thermoelectric figure of merit is calculated. When adding 0.15 wt % of graphene plates to a p-type solid solution, the maximum thermoelectric figure of merit (ZT)max of the material increases by 13% and is equal to 1.3 at 420 K. For a sample with n-type conductivity doped with graphene, the highest value of (ZT)max = 0.83 at 470 K is obtained by adding 0.1 wt % of graphene plates.

Basal melting of ice shelves around Antarctica contributes to formation of Antarctic Bottom Water and can affect global sea level by altering the offshore flow of grounded ice streams and glaciers. Tides influence ice shelf basal melt rate (wb) by contributing to ocean mixing and mean circulation as well as thermohaline exchanges with the ice shelf. We use a three‐dimensional ocean model, thermodynamically coupled to a nonevolving ice shelf, to investigate the relationship between topography, tides, andwb for Larsen C Ice Shelf (LCIS) in the northwestern Weddell Sea, Antarctica. Using our best estimates of ice shelf thickness and seabed topography, we find that the largest modeled LCIS melt rates occur in the northeast, where our model predicts strong diurnal tidal currents (∼0.4 m s−1). This distribution is significantly different from models with no tidal forcing, which predict largest melt rates along the deep grounding lines. We compare several model runs to explore melt rate sensitivity to geometry, initial ocean potential temperature (θ0), thermodynamic parameterizations of heat and freshwater ice‐ocean exchange, and tidal forcing. The resulting range of LCIS‐averagedwb is ∼0.11–0.44 m a−1. The spatial distribution of wb is very sensitive to model geometry and thermodynamic parameterization while the overall magnitude of wb is influenced by θ0. These sensitivities in wbpredictions reinforce a need for high‐resolution maps of ice draft and sub‐ice‐shelf seabed topography together with ocean temperature measurements at the ice shelf front to improve representation of ice shelves in coupled climate system models. Key Points Tide‐topography interactions influence ice shelf basal melt distribution Ice shelf geometry uncertainties limit our ability to accurately predict tides Better data are needed to quantify tide‐topography interactions

Molecular surveillance of FMD epidemiology is a fundamental tool for advancing our understanding of virus biology, monitoring virus evolution, and guiding vaccine design. The accessibility of genetic data will facilitate a more comprehensive delineation of FMDV phylogeny on a global scale. In this study, we investigated the FMDV strains circulating in Russia during the 2013–2014 period in geographically distant regions utilizing whole genome sequencing followed by maximum-likelihood phylogenetic reconstruction of whole genome and VP1 gene sequences. Phylogenetic analysis showed congruence in the topology of the phylogenetic trees constructed using the complete genome and VP1 gene sequence, clearly demonstrating that the isolates analyzed belong to two distinct genetic lineages: A/SEA97 in the Far East and Iran-05 in the North Caucasus. The A/SEA97 isolates exhibited a close genetic identity to those from China and Mongolia, whereas the Iran-05 isolates demonstrated clusterization with those from Turkey. The vaccine-matching studies with isolates from the Far East and North Caucasus revealed no antigenic homology with A/SEA-97 (r1 = 0.015–0.29) and A/Iran 05 (r1 = 0.009–0.17). The close genetic relationship of FMDV in the reported outbreak waves to those from neighboring countries indicates that animal movement could contribute to spillover and virus dispersal. The phylogenetic data reported here provide insight into the molecular epidemiology of FMD in the Eurasia region, elucidating the circulation pattern, molecular evolution, and genetic diversity, which is highly valuable for guiding vaccine designs and improving regional eradication policies.

The influence of the method used for synthesizing ZnO-In2O3 composites (nanopowder mixing, impregnation, and hydrothermal method) on the structure, conductivity, and sensor properties is investigated. With the nanopowder mixing, the size of the parent nanoparticles in the composite remains practically unchanged in the range of 50–100 nm. The impregnation composites consist of 70 nm In2O3 nanoparticles with ZnO nanoclusters < 30 nm in size located on its surface. The nanoparticles in the hydrothermal composites have a narrow size distribution in the range of 10–20 nm. The specific surface of hydrothermal samples is five times higher than that of impregnated samples. The sensor response of the impregnated composite to 1100 ppm H2 is 1.3–1.5 times higher than the response of the mixed composite. Additives of 15–20 and 85 wt.% ZnO to mixed and impregnated composites lead to an increase in the response compared with pure In2O3. In the case of hydrothermal composite, up to 20 wt.% ZnO addition leads to a decrease in response, but 65 wt.% ZnO addition increases response by almost two times compared with pure In2O3. The sensor activity of a hydrothermal composite depends on the phase composition of In2O3. The maximum efficiency is reached for the composite containing cubic In2O3 and the minimum for rhombohedral In2O3. An explanation is provided for the observed effects.

Terdiurnal atmospheric tides induce an S3 radiational ocean tide, similar to radiational tides S1 and S2 in the diurnal and semidiurnal bands. Although of small amplitude, the terdiurnal tide has some intriguing properties. The tide has an unusually pronounced seasonal variation, manifested by annual sidelines here denoted R3 and T3, which causes the tide to nearly vanish during times near an equinox. Forcing is generally largest in the winter hemisphere. Complicating matters, the two sideline frequencies coincide with those of nonlinear compound tides SK3 and SP3. Whether radiational tides or nonlinear tides (or both) are appearing at any given tide gauge can usually be determined by the relative amplitudes and phase differences of the two sidelines. The amplitudes of R3 and T3 are generally comparable; the amplitudes of SK3 and SP3 are not. Proper identification can lead to a small improvement in tidal prediction, but more importantly can lead to improved physical interpretation. An example from recent measurements under the Ross Ice Shelf bears on the role of nonlinearity in interactions between the ocean tide and the floating ice shelf.

Altimeter measurements are corrected for several geophysical parameters in order to access ocean signals of interest, like mesoscale or sub-mesoscale variability. The ocean tide is one of the most critical corrections due to the amplitude of the tidal elevations and to the aliasing phenomena of high-frequency signals into the lower-frequency band, but the internal-tide signatures at the ocean surface are not yet corrected globally. Internal tides can have a signature of several centimeters at the surface with wavelengths of about 50–250 km for the first mode and even smaller scales for higher-order modes. The goals of the upcoming Surface Water Ocean Topography (SWOT) mission and other high-resolution ocean measurements make the correction of these small-scale signals a challenge, as the correction of all tidal variability becomes mandatory to access accurate measurements of other oceanic signals. In this context, several scientific teams are working on the development of new internal-tide models, taking advantage of the very long altimeter time series now available, which represent an unprecedented and valuable global ocean database. The internal-tide models presented here focus on the coherent internal-tide signal and they are of three types: empirical models based upon analysis of existing altimeter missions, an assimilative model and a three-dimensional hydrodynamic model. A detailed comparison and validation of these internal-tide models is proposed using existing satellite altimeter databases. The analysis focuses on the four main tidal constituents: M2, K1, O1 and S2. The validation process is based on a statistical analysis of multi-mission altimetry including Jason-2 and Cryosphere Satellite-2 data. The results show a significant altimeter variance reduction when using internal-tide corrections in all ocean regions where internal tides are generating or propagating. A complementary spectral analysis also gives some estimation of the performance of each model as a function of wavelength and some insight into the residual non-stationary part of internal tides in the different regions of interest. This work led to the implementation of a new internal-tide correction (ZARON'one) in the next geophysical data records version-F (GDR-F) standards.

The results of geochemical studies of Paleoproterozoic volcanic rocks in the structure of the Polmak–Pechenga–Imandra–Varzuga belt of the northeastern part of the Fennoscandian Shield are presented. Taking into account new geochronological data, the volcanic series are correlated with subvolcanic and intrusive rocks of the Murmansk and Kola–Norwegian terranes. The comparative analysis of sections of volcanic rocks of the Imandra–Varzuga and Pechenga structures indicate asynchronous evolution of these fragments of the belt in a range of 2.51–2.40 Ga and a significant time gap (probably, >300 m.y.) in evolution of both the Imandra–Varzuga and Pechenga structures. The geochemical evidence is provided for the cyclic plume-lithospheric interaction during magmatism of the Sumian–Sariolian period, which shows that basic melts mostly generated from facies of spinel lherzolites exhibit features of significant crustal contamination as a result of their interaction with rocks of the Archean basement.

The study of the volcano–sedimentary sequence in the lower part of the Zaonega formation in the Paleoproterozoic Onega structure (Karelian craton, Fennoscandian Shield) has shown that tuffaceous and high-silica rocks predominate in its composition. High-silica rocks (SiO 2 up to 94 wt %) are depleted in all elements and probably represent chemogenic siliceous silts. Tuffaceous rocks vary broadly in composition and were formed during mixing of tuffogenous basalt material and high-silica chemogenic sediments. In terms of levels of contents and the distribution character of trace elements, tuffogenous rocks are close to N-MORB volcanic rocks. This rock association is typical of the early stages of continental rifting in the Phanerozoic and may indicate the formation of volcano–sedimentary complexes of the Zaonega formation in the environment of continental rifting. The tuffaceous rocks in the lower part of the Zaonega formation are geochemically identical to dolerite dikes and MORB-type volcanic rocks 2.10–2.14 Ga in age. Their formation was probably related to this episode of large-scale extension and thinning of the continental lithosphere of the Karelian craton in the Middle Paleoproterozoic. In this case, the age limit of the Zaonega and underlying Tulomozero formations should be somewhat older than the 2.06–2.10 Ga interval accepted in the modern regional stratigraphic schemes of the Paleoproterozoic Fennoscandian shield.