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The paper presents the results of a study of the charge and energy characteristics of multiply charged ions excited on the surface of a single-element and hydrogen-containing multi-component element targets under the influence of laser radiation with a power density (q=108-1012 W/cm2). It has been experimentally shown that, for all used values of q laser radiation, laser-induced plasma from gas-containing targets is characterized by a lower relative yield (dN/dE) of multi-charged ions with a charge number of Z>+3, compared to the plasma produced on the surface of the single element target. Moreover, the tendency to reduce dN/dE of multi-charged ions of the multi-element target, in comparison with the relative yield of ions from the plasma of the single-element target, is more significant and it depends on the charge of the excited ions. The increase in the charge and energy state, duration, and yield of ions of the heavy component, which occurs with an increase in the content of the light component in the target, has been established. This is explained by a decrease in the efficiency of recombination processes caused by an increase in the expansion velocity of a plasma plume due to a decrease in its average mass.

The article provides an assessment of climatic characteristics and changes in floodplain soils after the implementation of a drainage system. The study was conducted in the northern forest-steppe zone of the East European Plain (Republic of Bashkortostan, Russia). Through the analysis of long-term meteorological observations from 1961 to 2020, it was found that there was a steady increase in air temperature in all months and throughout the year, an increase in the period with positive temperatures, a slight increase in annual precipitation, and a reduction in precipitation during certain months of the warm season. Over the past 40 years, the drainage system has transformed the soil cover from Gleysols to Anthrosols, due to a decrease in the level of groundwater, agricultural use, as well as warming of the climate in the region. Thus, the transformation of soil cover can potentially contribute to climate change through the depletion of soil organic carbon stocks and increased greenhouse gas emissions. Nevertheless, currently, the natural and climatic conditions, morphological, water-physical, and agrochemical properties of Anthrosols allow for the production of two harvests of fodder crop (Bromus inermis L.) during the vegetation period. In general, the change in climatic indicators in the study area is consistent with the global trend. Our results underscore the sensitivity of soil systems to climatic variations and human activities, highlighting the need for local studies to understand regional and global environmental changes.

The primary data of micro- and macroplastics in the aquatic environment of Lake Markakol, located in the mountainous area of East Kazakhstan, are presented. The determination of micro- and macroplastics in water is based on sieving, drying, liquid oxidation, density separation and visual sorting using a microscope with a magnification of 40×. The detected plastic fragments in the aquatic environment include fishing line nets, Styrofoam balls, plastic bags, plastic bottles, wrappers, food labels and packages and other types of plastic waste. The sizes of the plastic fragments were ˃25 mm, 1.0–5.0 mm and 0.315–1.0 mm. The concentration of plastic in Lake Markakol was 837.5 µg/m3 in the tributaries and 482.1 µg/m3 in the lake water. The detected plastic mainly corresponded to sieve mesh sizes of 1.0–5.0 mm and 0.315–1.0 mm. The main sources of plastic pollution are fishing, tourism and the lack of adequate infrastructure for household waste management. These data emphasize the importance of measures to regulate plastic waste management in order to preserve the Lake Markakol ecosystem and maintain human health.

The research presented in the article is devoted to the study of the influence of phase compounds on the friability of the Fe-Si-Mn-Al complex alloy. The urgency of the problem lies in the development of technology for producing a non-scatterable alloy from manganese-containing ores and high-ash coals. The main goal of this work is to determine the range of alloy compositions and the resulting phases that affect the dispersibility of the alloy, which is critically important for its industrial implementation. Research methods include thermodynamic diagram analysis (TDA) using data on the standard enthalpy of formation of intermetallic compounds, as well as experimental tests in an ore-thermal electric furnace with a capacity of 200 kV*A. The results show that Fe-Si-Mn-Al complex alloys form a variety of silicide and aluminide phases, including intermetallic compounds and ternary systems, which is critical for understanding and controlling their physicochemical properties. When melting a complex alloy, the content of leboite (Fe3Si7) in the Fe-Si-Mn-Al system plays a significant role. The development of melting process technology will be aimed at avoiding the FeSi2-Fe3Si7-F2(FeAl3Si2)-Mn11Si19 tetrahedron area. This approach to controlling the composition of a complex alloy is critical to ensuring its consistent friability properties in industrial applications. Thus, this work represents an important step in understanding the physical properties and stability of Fe-Si-Mn-Al complex alloys, which have potential for widespread use in metallurgical and other industrial applications.

Nowadays, biodegradable metals and alloys, as well as their corrosion behavior, are of particular interest. The corrosion process of metals and alloys under various harsh conditions can be studied via the investigation of corrosion atom adsorption on metal surfaces. This can be performed using density functional theory-based simulations. Importantly, comprehensive analytical data obtained in simulations including parameters such as adsorption energy, the amount of charge transferred, atomic coordinates, etc., can be utilized in machine learning models to predict corrosion behavior, adsorption ability, catalytic activity, etc., of metals and alloys. In this work, data on the corrosion indicators of Zn surfaces in Cl-, S-, and O-rich harsh environments are collected. A dataset containing adsorption height, adsorption energy, partial density of states, work function values, and electronic charges of individual atoms is presented. In addition, based on these corrosion descriptors, it is found that a Cl-rich environment is less harmful for different Zn surfaces compared to an O-rich environment, and more harmful compared to a S-rich environment.

Lake Markakol is located in a metal-rich mountain area of Kazakhstan. Metal input into the lake water and in the bottom sediments can be expected. Lead, cobalt and nickel monitoring in both near-surface and deep-water layers and in bottom sediments was carried out using flame atomic absorption spectrometric analyses. Lead contamination of surface water ranging from 2.6 to 6.8 µg/L occurs in all water samples with the exception of the surface water layer. In the deep-water section concentrations reach up to 13.0–16.2 µg/L. Cobalt concentrations range from 36.8 to 67.5 µg/L in the surface layer and from 25.5 to 69.2 µg/L in the deep-water layer. High values of nickel were found in the surface and bottom layers of the water, ranging from 13.5 to 49.0 and 17.2 to 49.0 µg/L, respectively. High concentrations of lead, cobalt and nickel were identified in all samples of the bottom sediments. The lead content in bottom sediments reaches 11.3, cobalt reaches 10.3–18.0 and nickel reaches 15.0 mg kg−1. The results and their assessment can serve as a basis for future monitoring and measures to reduce pollution, restore the lake ecosystem and ensure the safety of fishery products for humans.

This study investigates the physical, mechanical, and structural characteristics of handmade paper samples derived from cellulose extracted from grass clippings using two distinct methods as follows: (1) alkali treatment and (2) alkali treatment followed by bleaching, coupled with the incorporation of barium sulfate as a mineral filler. Our investigation revealed that the handmade paper samples’ densities, moisture contents, and thicknesses varied within the ranges of 0.436 to 0.549 g/cm3, 5.60 to 2.51%, and 0.41 to 0.50 mm, respectively. The tensile strength and folding endurance of the papers produced through alkali treatment with barium sulfate were notably superior to those produced from bleached pulp and barium sulfate. Our analysis indicates that several critical factors, including paper density, thickness, the crystallinity index, and the microfibrillar structure of cellulose, intricately influence the mechanical and strength properties of the samples. Using Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) techniques, we identified characteristic cellulose bonds and examined cellulose’s crystalline and amorphous phases. Additionally, the crystallinity index of the samples was determined using both the Segal and peak deconvolution methods. Scanning electron microscopy (SEM) micrographs revealed interconnected networks of cellulose fibers with varying thicknesses and lengths, along with incorporated mineral filler within the cellulose fiber structure. Variations in mineral particle retention were attributed to the presence or absence of cellulose microfibrils. These findings contribute to our understanding of the observed strength characteristics of the paper samples and underscore the potential applications of cellulose derived from grass clippings, especially when combined with barium sulfate as a mineral filler in paper production.

Background: Hypoxia and old age impair postural control and may therefore enhance the risk of accidents. We investigated whether acetazolamide, the recommended drug for prevention of acute mountain sickness, may prevent altitude-induced deterioration of postural control in older persons.Methods: In this parallel-design trial, 95 healthy volunteers, 40 years of age or older, living

We present a systematic search for optical counterparts to 13 gravitational wave (GW) triggers involving at least one neutron star during LIGO/Virgo's third observing run (O3). We searched binary neutron star (BNS) and neutron star black hole (NSBH) merger localizations with the Zwicky Transient Facility (ZTF) and undertook follow-up with the Global Relay of Observatories Watching Transients Happen (GROWTH) collaboration. The GW triggers had a median localization area of 4480 deg2, a median distance of 267 Mpc, and false-alarm rates ranging from 1.5 to 10-25 yr-1. The ZTF coverage in the g and r bands had a median enclosed probability of 39%, median depth of 20.8 mag, and median time lag between merger and the start of observations of 1.5 hr. The O3 follow-up by the GROWTH team comprised 340 UltraViolet/Optical/InfraRed (UVOIR) photometric points, 64 OIR spectra, and three radio images using 17 different telescopes. We find no promising kilonovae (radioactivity-powered counterparts), and we show how to convert the upper limits to constrain the underlying kilonova luminosity function. Initially, we assume that all GW triggers are bona fide astrophysical events regardless of false-alarm rate and that kilonovae accompanying BNS and NSBH mergers are drawn from a common population; later, we relax these assumptions. Assuming that all kilonovae are at least as luminous as the discovery magnitude of GW170817 (-16.1 mag), we calculate that our joint probability of detecting zero kilonovae is only 4.2%. If we assume that all kilonovae are brighter than-16.6 mag (the extrapolated peak magnitude of GW170817) and fade at a rate of 1 mag day-1 (similar to GW170817), the joint probability of zero detections is 7%. If we separate the NSBH and BNS populations based on the online classifications, the joint probability of zero detections, assuming all kilonovae are brighter than-16.6 mag, is 9.7% for NSBH and 7.9% for BNS mergers. Moreover, no more than 10-4, or φ > 30° to be consistent with our limits. We look forward to searches in the fourth GW observing run; even 17 neutron star mergers with only 50% coverage to a depth of-16 mag would constrain the maximum fraction of bright kilonovae to

The authors publish the results of architectural and archaeological research of the medieval bath house carried out on the territory of the settlement Khankurgan in 2015–2016. During the excavations, six rooms were unearthed, two of which were built of burned bricks and turned out to be “steam rooms” with an underfloor heating system, the remaining four were frame rooms – “washing rooms”. All rooms are covered with waterproof mortar and plaster. Their original layer was decorated with red-brown drawings, carved stucco and moldings. The plaster has been updated more than twenty times in the course of multiple repairs. Two major reconstructions of the bathhouse were recorded, which did not affect the "hot" rooms, due to which their original layout was preserved. The stages of restructuring and repair work for the entire period of operation of the hammam are determined. The Khankurgan bath house is well preserved and is a unique example of medieval architecture of the Samanid era, it belongs to rather early examples of such structures that arose at the middle of the 9th century. Functioning until the middle of the 11th century, it gives us a represent of the features of the architectural and construction techniques used in the building of the baths of the pre-Mongolian era in Kazakhstan. Hammam Khankurgan, being a vivid example of the medieval architecture, allows to determine the time of the emergence of this culture in the Ispidzhab historical and cultural region, clarifying its planning, constructive and shaping principles, reflecting in general the cultural and economic connection of the region with the Muslim world.

Reverse osmosis desalination facilities operating on microgrids (MGs) powered by renewable energy are becoming more significant. A leader-follower structured optimization method underlies the suggested algorithm. The desalination plant is divided into components, each of which can be operated separately as needed. MGs are becoming an important part of smart grids, which incorporate distributed renewable energy sources (RESs), energy storage devices, and load control strategies. This research proposes novel techniques in economic saline water treatment based on MG architecture integrated with a renewable energy systems. This study offers an optimization framework to simultaneously optimize saline as well as freshwater water sources, decentralized renewable and conventional energy sources to operate water-energy systems economically and efficiently. The radial Boltzmann basis machine is used to analyse the salinity of water. Data on water salinity were used to conduct the experimental analysis, which was evaluated for accuracy, precision, recall, and specificity as well as computational cost and kappa coefficient. The proposed method achieved 88% accuracy, 65% precision, 59% recall, 65% specificity, 59% computational cost, and 51% kappa coefficient. HIGHLIGHTS Novel method in economic saline water treatment based on microgrid architecture integrated with a renewable energy system.; An effective and cost-effective water-energy system can be operated by using an optimization framework that simultaneously improves salty and freshwater water sources as well as decentralized renewable and conventional energy sources.; Salinity of water is analysed using a radial Boltzmann basis machine.;

Bilgi ve iletişim teknolojilerinin kurum ve kuruluşlar tarafından benimsenmesi hızla sürerken, durumun ülkelere göre, sektörlere göre farklılık göstermesi de bilinen bir gerçektir. Bu çalışmada Kırgızistan’da faaliyet göstermekte olan özel ve devlet üniversitelerinin Instagram kullanım durumları değerlendirilmektedir. Çalışmada öncelikle Instagram’ı aktif olarak kullanmakta olan üniversiteler belirlenmiş ve onların paylaşımları içerik analizine tabii tutulmuştur. İçerik analizi takipçi sayısı, paylaşımların formatı, dile göre dağılımı, takipçilerin tepkisi gibi kriterlere göre yapılmış ve karşılaştırmalı olarak analiz edilmiştir.Araştırma sonuçlarına göre, Kırgızistan’da üniversitelerin %43,3’ünün Instagram’a kayıtlı oldukları ve çok az bir kısmının aktif olarak kullandıkları tespit edilmiştir. Çalışmanın sonuçları Kırgızistan’daki üniversitelerin sosyal medya pazarlaması konusundaki genel durumunu görmeleri ve daha etkili olabilmeleri için gerekli olan ipuçlarını sağlaması açısından önemlidir.