Short-term Mechanical Properties of Fe-Cr-Al-Si Alloys

The purpose of this work is to study the short-term mechanical properties of Fe-Cr-AlSi-based alloys. Within the framework of this work, alloys with a chromium content of 5 to 14 wt%, aluminum from 0 to 4 wt%, and silicon from 0 to 4 wt% are considered. The samples were tested in three different states - in the deformed state (cold rolling by 80%), and also after annealing at a temperature of 450 and 650 ∘C with a duration of 1000 h.As a result, the characteristics of the strength and plasticity of alloys in the deformed state, as well as after provoking annealing, were obtained. It is shown that embrittlement isn’t observed in the investigated composition region and annealing conditions, and the strength of the alloys is directly proportional to the sum of the alloying elements Al + Si. Keywords: cladding; VVER; tolerant fuel, ferrite steel; Corrosion-resistant steel, tensile strength, yield strengt

Layered and Hexagonal Perovskites as Novel Classes of Proton-Conducting Solid Electrolytes. A Focus Review

Received: 15 September 2022. Accepted: 28 September 2022.Solid oxide electrolytes have attracted significant attention due to their possible applications in energy conversion devices, including solid oxide fuel cells (SOFCs) and electrolysis cells (SOECs). Although a large amount of data has been accumulated to date, the design of new representatives of ionic electrolytes is of unquenchable interest. In this paper, a review of the new classes of proton-conducting solid electrolytes is provided. The physicochemical and transport properties of layered perovskites (BaNdInO4, BaNdScO4, SrLaInO4, BaLaInO4) and hexagonal perovskites (Ba7Nb4MoO20, Ba5Er2Al2ZrO13 and Ba5In2Al2ZrO13) were analyzed and summarized. Based on the performed analysis, the most promising compositions among the considered phases were identified and the effective approaches aimed at improving their functional characteristics were provided.This work was supported by the Russian Science Foundation (grant no 22-79-10003)

Protonic Transport in Layered Perovskites BaLanInnO3n+1 (n = 1, 2) with Ruddlesden-Popper Structure

The work focused on the layered perovskite-related materials as the potential electrolytic components of such devices as proton conducting solid oxide fuel cells for the area of clean energy. The two-layered perovskite BaLa2 In2O7 with the Ruddlesden–Popper structure was investigated as a protonic conductor for the first time. The role of increasing the amount of perovskite blocks in the layered structure on the ionic transport was investigated. It was shown that layered perovskites BaLanInnO3n+1 (n = 1, 2) demonstrate nearly pure protonic conductivity below 350◦C. © 2022 by the authors. Licensee MDPI, Basel, Switzerland

Spirulina: growth in continuous and batch bioreactors and response to stress conditions

The purpose of this work was to develop and compare methods for cultivating Spirulina platensis in two bioreactors, continuous and batch ones, and to assess the resistance of spirulina cells to environmental stress caused by the presence of household chemicals. It was shown that, at room temperature, the wet biomass yield was higher in the bioreactor than with batch cultivation in flask

High-temperature transport properties of BaSn1−xScxO3−δ ceramic materials as promising electrolytes for protonic ceramic fuel cells

Protonic ceramic fuel cells (PCFCs) offer a convenient means for electrochemical conversion of chemical energy into electricity at intermediate temperatures with very high efficiency. Although BaCeO3- and BaZrO3-based complex oxides have been positioned as the most promising PCFC electrolytes, the design of new protonic conductors with improved properties is of paramount importance. Within the present work, we studied transport properties of scandium-doped barium stannate (Sc-doped BaSnO3). Our analysis included the fabrication of porous and dense BaSn1−xScxO3−δ ceramic materials (0 ⩽ x ⩽ 0.37), as well as a comprehensive analysis of their total, ionic, and electronic conductivities across all the experimental conditions realized under the PCFC operation: both air and hydrogen atmospheres with various water vapor partial pressures (p(H2O)), and a temperature range of 500–900 °C. This work reports on electrolyte domain boundaries of the undoped and doped BaSnO3 for the first time, revealing that pure BaSnO3 exhibits mixed ionic-electronic conduction behavior under both oxidizing and reducing conditions, while the Sc-doping results in the gradual improvement of ionic (including protonic) conductivity, extending the electrolyte domain boundaries towards reduced atmospheres. This latter property makes the heavily-doped BaSnO3 representatives attractive for PCFC applications. [Figure not available: see fulltext.] © 2022, The Author(s).We would like to give special thanks to Natalia POPOVA and Thomas BEAVITT for their performed proofreading

Formation of a disk-structure and jets in the symbiotic prototype Z And during its 2006-2010 active phase

We present an analysis of spectrophotometric observations of the latest cycle of activity of the symbiotic binary Z And from 2006 to 2010. We estimate the temperature of the hot component of Z And to be \approx 150000 - 170000 K at minimum brightness, decreasing to \approx 90000 K at the brightness maximum. Our estimate of the electron density in the gaseous nebula is N_{e}=10^{10}-10^{12} cm^{-3} in the region of formation of lines of neutral helium and 10^6-10^7 cm^{-3} in the region of formation of the [OIII] and [NeIII] nebular lines. A trend for the gas density derived from helium lines to increase and the gas density derived from [OIII] and [NeIII] lines to simultaneously decrease with increasing brightness of the system was observed. Our estimates show that the ratios of the theoretical and observed fluxes in the [OIII] and [NeIII] lines agree best when the O/Ne ratio is similar to its value for planetary nebulae. The model spectral energy distribution showed that, in addition to a cool component and gaseous nebula, a relatively cool pseudophotosphere (5250-11 500 K) is present in the system. The simultaneous presence of a relatively cool pseudophotosphere and high-ionization spectral lines is probably related to a disk-like structure of the pseudophotosphere. The pseudophotosphere formed very rapidly, over several weeks, during a period of increasing brightness of Z And. We infer that in 2009, as in 2006, the activity of the system was accompanied by a collimated bipolar ejection of matter. In contrast to the situation in 2006, the jets were detected even before the system reached its maximum brightness. Moreover, components with velocities close to 1200 km/s disappeared at the maximum, while those with velocities close to 1800 km/s appeared.Comment: 18 pages, 19 figures, Accepted for publication in Astronomy Report

Impact of preoperative mild cognitive impairment on cerebrovascular events and cognitive status in patients undergoing coronary artery bypass grafting: data from 5-year follow-up

Aim. To assess the incidence of cerebrovascular events and cognitive status in the long-term period after coronary artery bypass grafting (CABG) in patients with and without preoperative mild cognitive impairment (MCI).Material and methods. This prospective study involved 115 patients aged 45 to 69 years, who were admitted to the hospital for elective on-pump CABG. All patients underwent clinical, laboratory, ultrasound, neuroimaging and neuropsychological examination 3-5 days before and 5-7 years after CABG. Cognitive functioning was assessed using screening neuropsychological scales and neuropsychological testing with an assessment of neurodynamics, attention and short-term memory. Pre-CABG MCI was diagnosed based on the criteria by R. Petersen et al. Therefore, the patients were divided into two groups: with (n=51) and without MCI (n=64).Results. It was found that strokes and dementia during the long-term postoperative period of CABG were observed only in the group of patients with preoperative MCI (7,84%). Five-seven years after CABG, a decrease in cognitive status according to neuropsychological scales was found in all patients (p≤0,05). A decrease in neurodynamics, attention and short-term memory compared to the preoperative level was found in 47,92% of patients with preoperative MCI, without MCI — in 40,63%. Neurodynamic disorders occurred equally frequently in both groups (63,8% and 57,8% of patients, respectively). Memory impairments were more often observed in patients with MCI (55,3%) compared to those without MCI (34,4%) (OR=2,36, 95% CI, 1,09-5,12, p=0,03). According to brain multislice computed tomography in the group with preoperative MCI, the number of patients with cysts and leukoaraiosis 5-7 years after CABG was higher than in those without MCI (p≤0,05).Conclusion. In the long-term (5-7 years) postoperative period of CABG, more than 40% of patients demonstrate a decrease in cognitive status, regardless of preoperative data. At the same time, preoperative MCI is associated with adverse cerebrovascular events and dementia, accompanied by morphological brain abnormalities. Due to the revealed facts, it is necessary to optimize approaches to drug treatment and secondary prevention of cognitive decline after cardiac surgery

Modification of Copper Alloyed Cast Irons

В работе исследовалось влияние модифицирования на чугуны, содержащие ~9 мас. % меди. Исследовалось влияние на стрктуру и механические свойства 0,3 мас. % NiMg (17 % Mg), РЗМ (цериевая группа) и SiCa.The work investigated the effect of modification on cast irons containing ~ 9 wt. % copper. The effect on the structure and mechanical properties of 0.3 wt. % NiMg (17 % Mg), rare earth metals (cerium group) and SiCa

Detection of Atmospheric Muon Neutrinos with the IceCube 9-String Detector

The IceCube neutrino detector is a cubic kilometer TeV to PeV neutrino detector under construction at the geographic South Pole. The dominant population of neutrinos detected in IceCube is due to meson decay in cosmic-ray air showers. These atmospheric neutrinos are relatively well-understood and serve as a calibration and verification tool for the new detector. In 2006, the detector was approximately 10% completed, and we report on data acquired from the detector in this configuration. We observe an atmospheric neutrino signal consistent with expectations, demonstrating that the IceCube detector is capable of identifying neutrino events. In the first 137.4 days of livetime, 234 neutrino candidates were selected with an expectation of 211 +/- 76.1(syst.) +/- 14.5(stat.) events from atmospheric neutrinos