Wetting Layer Research Articles

A comparative study of the atmospheric water vapor in the Atacama and Namib Desert

The importance of water vapor in arid and hyperarid regions motivates a comparative study in the Atacama and Namib deserts, a natural laboratory to test the role of topography in present-day climate. Based on ERA5 reanalysis evaluated by satellite and ground-based instruments, we focus on the climatological water vapor seasonal cycle and interannual variability offshore the deserts, distinguishing between the free troposphere (FT) and the marine boundary layer (MBL) moisture. In the Namib, moisture variability is strongly controlled by air mass transport. For example, between austral fall and winter, an easterly continental warm and cloud-free air mass settles over the coast, reducing the MBL height to a few hundred meters and decreasing humidity. In summer, the easterly winds are also present, bringing moisture from the center of the continent to the FT of the Namib, along with clouds and rainfall. This feature is intensified during the cold phase of ENSO (La Niña). In contrast, the Andean Cordillera blocks any air mass exchange between the continent and the MBL in the Atacama, allowing the development of stable southerly winds along the coast that transport cold air over warmer waters due to the early westward turn of the Humboldt Current. This induces a strong coupling between SST and MBL moisture, which is enhanced by a permanent stratocumulus cloud cover. In addition, the FT remains drier than the Namib for most of the year due to the predominance of westerly dry air in the region. ENSO is not correlated with the MBL moisture offshore Atacama, and it is the local SST that plays a major role in modulating interannual moisture variability. Only in winter, ENSO seems to impact the FT by increasing the moisture transport from the mid-latitudes during the warm phase (El Niño). We hypothesize that the differences in moisture seasonality and its controlling mechanisms are strongly related to differences in topography and the resulting circulation patterns. Furthermore, similar moisture transport and variability may have been part of a Paleo-Atacama when its topography was similar to the present-day Namib Desert.

Analysis of an Arctic cold air outbreak during autumn and related air mass transformations forced by surface changes and advection in higher altitudes

During marine cold air outbreaks (MCAOs), cold and dry Arctic air masses are transported from the central Arctic southward across the closed sea ice and much warmer open oceans. They experience significant transformations including a rapid heating and moistening, often leading to cloud formation. While intense wintertime MCAOs have been analyzed widely, the air mass transformations during other seasons have been studied sparsely. We address this gap by investigating an MCAO case observed in September 2020. To study the transformation processes, we combine the fifth generation of atmospheric reanalyses of the global climate (ERA5), trajectory calculations, as well as shipborne and airborne measurements. In the central Arctic, observations acquired from aboard the research vessel (RV) Polarstern during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition characterized the initial state of the air mass over closed sea ice. Trajectories indicated the pathway the air mass took from RV Polarstern southward to the Fram Strait. For the first 24 h of the southbound drift, the air masses remained quasi-stationary. Then, still 15 h ahead of the marginal sea ice zone, differential advection across the boundary layer flow introduced humidity and clouds at higher altitudes between 1.5 and 2.5 km. ERA5-derived temperature and humidity tendencies indicated complex vertical interactions. Radiative cloud-top cooling, entrainment, and turbulence were significantly reduced in the lower and enhanced in the upper advected cloud layer. Eventually, the lower cloud deck dissipated. After this confluence of 2 different air masses, observations gathered by Polar 5 in Fram Strait as part of the MOSAiC Airborne observations in the Central Arctic campaign revealed cloudy, moist layers throughout the lowest 3.5 km and an increasing boundary layer height. Comparing the initial with the final state 48 h later, the largest net heating of +8 K was found close to the surface, yet the largest net moistening of +2.5 g kg−1 at an altitude of 1 km, as the initial profile was exceptionally dry here. We conclude that the observed air mass transformations were driven by the surface changes from sea ice to open ocean but additionally strongly impacted by the differential advection of clouds and moisture across the near-surface MCAO flow.

Microstructure and performance enhancement of the TiN/Fe-based cladding layer induced by mechanical vibration assisted underwater wet laser cladding

It is challenging to obtain the underwater wet laser cladding layer with excellent properties while maintaining formability. In this paper, the method of using synchronous mechanical vibration assisted in the underwater wet laser cladding process of TiN/Fe-based cladding layer was introduced. The effect of mechanical vibration frequency on the dilution rate, microstructure, corrosion resistance, tribo-corrosion behavior of the cladding layer was studied. The result displayed that with increase of mechanical vibration frequency, the dilution effect of the substrate was obviously weakened and the phase changed from ferrite to ferrite and austenite, and TiN particles were evenly distributed. In addition, the grain size of the cladding layer showed a tendency to decrease first and then increase. When the mechanical vibration frequency was 400 Hz, the grain refinement phenomenon was the most obvious and the average grain size was 8.39 μm. Based on the effect of dispersion strengthening and fine grain strengthening, the microhardness and wear resistance of the cladding layer assisted at 400 Hz were improved, and the wear rate was 1.17 × 10−15m3N−1 m−1. While the cladding layer assisted at 400 Hz exhibited better corrosion resistance by forming a dense passivation film. In addition, the mechanism of mechanical vibration on microstructure evolution and performance enhancement of the cladding layer was also analyzed. This study provided the theoretical support for the formability of the underwater laser wet cladding assisted by mechanical vibration.

Effect of metal seed layer on the critical thickness and photoelectric properties of ultrathin Ag films

To decrease the critical thickness for Ag to form a continuous film and improve the photoelectric properties of the transparent conductive film, the metal seed layer was introduced as a wetting layer, and the metal seed/Ag/AZO composite film was prepared on K9 glass substrates by the magnetron sputtering equipment. The effects of the metal seed layer on both the critical thickness of continuous Ag layer and the photoelectric properties of composite film were investigated. The Al seed layer reduces the critical thickness of the Ag layer to 10 nm, and the square resistance of the Al/Ag (10 nm)/AZO composite film decreases by 5.53 Ω/sq compared to the Ag(10 nm)/AZO bilayer film, while its average transmittance of visible light (380–780 nm) increases by 2.33 %. The Cu seed layer further reduces the critical thickness of the Ag film to 8 nm, and the square resistance of the Cu/Ag(8 nm)/AZO composite film decreases to 9.26 Ω/sq, of which average visible light transmittance reaches 69.34 %. The square resistance of the Cu/Ag (10 nm)/AZO composite film is as low as 7.43 Ω/sq, which is 8.48 Ω/sq lower than that of the Ag (10 nm)/AZO bilayer film.

Study of contemporary climate changes in the Ukrainian humid zone (on the example of the Volyn Region)

Modern agricultural production is under the direct influence of climatic changes, which is also reflected in the water regime formation of the soil during the cultivation of crops. Calculations were made and graphical materials were created for average daily, average decadal, and average monthly values of temperatures and the amount of precipitation per day, month, and year. The influence of modern climatic factors on the water regime formation of the soil (according to the data of the weather station of the city of Kovel, Volyn region) over the last 11-year period has been established. It was determined that the distribution of precipitation is as follows: the share of light precipitation (< 3 mm) is on average 13.9%, moderate (4–14 mm) is 43.3%, significant (15–49 mm) is 36.4%, strong (50–79 mm) is 5.4%, and extraordinary (80–100 mm) is 1% of the total amount. It was determined that the active layer of the soil is formed due to the influence of moderate and significant precipitation. Informational materials on the distribution of atmospheric precipitation by year in quantitative and percentage indicators and their repeatability are presented in an interactive visual report with graphic materials (dashboard), which allows the processing of large arrays of data. It was determined that modern climatic changes (increased air temperature, uneven distribution, change in the nature, intensity, and structure of precipitation, and the increase in the number of cases of heavy downpours that are local in the warm period of the year) don’t allow for the effective accumulation of moisture in the active soil layer. The obtained information materials are the basis for developing a methodology for substantiating the parameters of the management of the soil-water regime on reclaimed lands, taking into account the peculiarities of its formation in modern economic conditions and climate changes.

Relative-Humidity Dependence of Electrochemically Active Surface Area in Porous Carbon Catalyst Layers

Polymer-electrolyte fuel cells (PEFCs) utilize porous catalyst layers (CLs) formed of carbon supports on which Pt particles are deposited and ionomer films are distributed. Carbon supports themselves have varying degrees of porosity, where high-surface-area carbon (HSC) supports possess nanometer-sized interior pores that are suitable for Pt nanoparticle deposition but prevent deleterious ionomer penetration. However, this requires protons to transport through water pathways inside the pores. To understand the generation of such pathways, we examine the various mechanisms of water uptake by PEFC CLs, and the subsequent impact of water uptake on Pt utilization through developing a multiphysics model of the water wetting phenomena as a function of relative humidity. The model details water uptake via ionomer absorption, capillary condensation in the hydrophilic pores, and surface adsorption using molecular potential that account for various water and surface dipole interactions. The results quantify how mesoporous carbons with highly hydrophilic pores increase Pt utilization through the development of wetted layers, which at the same time enable optimized gas-transport pathways. It also demonstrates the impact of pore-size distribution (PSD) and physical and chemical parameters on the water uptake phenomena, allowing for future CL particle and structure optimization.

Vegetation communities and summer net ecosystem CO2 exchange on western Axel Heiberg Island, Canadian High Arctic

Climate change is expected to result in the Arctic transitioning from a carbon sink to a carbon source environment, with models predicting half of the carbon stock of the upper 3 m soil layer to be released by the year 2300 (van Huissteden and Dolman 2012). However, uncertainty in latitudinal warming and changes in Arctic ecosystem functions, such as gross carbon ecosystem exchange (GEE), are poorly understood, in part a reflection of a high variability in vascular plant community diversity that is dependent upon and sensitive to physiographic controls, such as soil moisture, topography, and seasonal active layer depth (Walker et al. 2005). This heterogeneity complicates assessments of carbon fluxes on a landscape scale and how they will change in the future (Shaver et al. 2007), especially given their sensitivity to local changes in climate, such as warming and higher rates of rainfall (Bintanja 2018, Bintanja and Andry 2017). As part of the creation of a long-term ecological and environmental monitoring program at the McGill Arctic Research Station at Expedition Fiord, western Axel Heiberg Island, field-based studies in 2021-2022 of plant surveys and summer net ecosystem CO2 exchange monitoring were undertaken to: define the major vegetation communities; quantify and investigate CO2 fluxes with chambers and their analogous biophysical variables; and upscale plot level CO2 measurements to the landscape scale using high spatial resolution remote sensing data. define the major vegetation communities; quantify and investigate CO2 fluxes with chambers and their analogous biophysical variables; and upscale plot level CO2 measurements to the landscape scale using high spatial resolution remote sensing data. The Expedition Fiord area is recognized as a polar oasis, with high plant species richness existing within an environment of heterogeneous physiography. At the moment, five vegetation communities have been identified (xeric dwarf shrub barren, xeric-mesic dwarf shub barren, mesic dwarf shrub tundra, cassiope heath, and sedge meadow) that varied as a function of species diversity, percent cover, soil moisture, and net ecosystem carbon exchange. Barren vegetation communities having stronger respiration fluxes (i.e., carbon source environments) while more vegetated communities have stronger photosynthesis fluxes (i.e., carbon sink environments). Landcover classification revealed with high accuracy (79.3%) that barren ground and barren vegetation communities cover a much larger area compared to wetter habitats. Upscaling summer season measured carbon fluxes based on the landcover map revealed that Expedition Fiord is a carbon source environment, with an average efflux of +94.6 g CO2/day. Ongoing work focuses on the expansion of carbon flux and subsurface monitoring locations, as well as studies of soil carbon and microbial diversity across the different land cover classifications, which will help to better resolve how soil microorganisms, plant detritus, labile organic carbon, soil moisture, slope, aspect, and bedrock geology influence CO2 fluxes throughout the summer season in this high Arctic setting.

Effect of nano-ZrO2 protective layer on the microstructure and surface property strengthening mechanism of underwater wet laser Fe-based cladding layer

Underwater wet laser cladding technology has become one of the research hotspots in the marine engineering, but the existence of the water environment inevitably leads to process instability and defects. In this study, the nano-ZrO2 protective layer was used to increase the viscosity of the molten pool surface to resist the impact force generated by the high-speed water jet, and the underwater wet laser Fe-based cladding layer with good forming quality and desirable performance was successfully prepared. The nano-ZrO2 protective layer improved the formability of the cladding layer and guaranteed the depth of the melt pool, while reducing the depth of the heat affected zone. The addition of nano-ZrO2 particles reduced the average grain size of the cladding layer from 4.90 μm to 3.66 μm. In addition,the corrosion resistance of the cladding layer was greatly improved with the application of the nano-ZrO2 protective layer, with the evident passivation region of 0.74 V. The wear rate of the cladding layer with the nano-ZrO2 protective layer (0.64×10-15m3N-1m-1) was significantly lower than that of the substrate (9.01×10-15m3N-1m-1), and the excellent wear resistance of the cladding layer with nano-ZrO2 protective layer benefited from the good carrying capacities and high microhardness of the microstructure with ZrO2 particles. This study reveals the strengthening mechanism of nano-ZrO2 protective layer on the Fe-based cladding layer, which can provide theoretical guidance for the development of the underwater laser cladding.

Preliminary identification of a series of finds from the excavation site on the territory of the town of the first Kostroma Kremlin

In 2022, a series of finds characterising the early history of the city of Kostroma was revealed on the territory of the town of the first Kostroma Kremlin, in close proximity to the Volga River, where the groundwater level is particularly high (the so-called wet cultural layer). The excavation site identified the location of the wooden Church of the Assumption of the Blessed Virgin Mary with side chapels, which had first been mentioned in the Scribe’s Book of 1629, as well as the stockade separating the church territory with the necropolis from the Assumption Lane. The stockade, made of stakes dug in close to each other, was revealed literally two meters from the church, and immediately behind it is the wooden pavement of the pre-regular Assumption Lane. A medieval necropolis has been identified between the stockade and the church, on the church territory. Later, in 1783, a stone church of the same name was erected on the site of the wooden church. It is noteworthy that some finds also give an idea of how the funeral rites changed with the adoption of Christianity among the local population.

MA-SARNet: A one-shot nowcasting framework for SAR image prediction with physical driving forces

Remote sensing imagery is one of the most widely used data sources for large-scale Earth observations with consistent spatial and temporal quality. However, the current usage scenarios of Earth’s surface remote sensing images, such as those generated from Landsat, Sentinel 2, and SAR, are largely limited to retrospective tasks, as they are often used to reconstruct existing phenomena, such as land use change, flood inundation, and wildfire. This study proposes MA-SARNet, a one-shot nowcasting framework built with a modified MA-Net structure and ResNet50 as the backbone, to predict the backscatter values of Synthetic-Aperture Radar (SAR) images using the previous SAR observations, precipitation, soil moisture, and geomorphic data layers as input. The model was trained, validated, and tested with SAR images collected during the catastrophic 2019 Midwest U.S. Floods that affected several states on the Missouri and Mississippi River tributaries. Compared to the benchmark performance, model predictions show an increase of 31.9% and 17.8% for the mean and median AAI (Assemble Accuracy Index) and an increase of 37.9% and 15.1% for the mean and median NSE (Nash-Sutcliffe Efficiency) on the test set. Results showed that the flood extent derived from backscatter predictions has less misclassifications caused by pixel-level noise compared to the flood map derived using the real backscatters. Results from spatial and temporal robustness tests demonstrate that the model has sufficient generalization potential and does not require further fine-tuning to work with new data, and therefore proves its usefulness in real-time Earth surface prediction tasks that are aimed at fast response to and mitigation for upcoming floods on a tight time schedule.

Solid wetting layer, interphase formation, and thin-film nanomaterials. Brief review

A review of the results on the formation of the interface between 3d metals and silicon silicides under identical conditions for various parameters of the deposited vapor, crystallographic orientation and substrate temperature is presented. A generalization of the results has been carried out, which consists of the fact that during the process of deposition of hot vapor on a colder substrate, the transition from the surface phase to the bulk phase occurs through a solid wetting layer (SWL). A classification of substrate-stabilized phases, including SWL, is proposed. It has been shown that SWL has an electronic density different from bulk phases, a smooth or nanostructured morphology, optical, electrical, and magnetic properties, and plays an important role in the formation of interfaces between bulk phases, their epitaxial films and multilayer nanostructures. These studies suggest the promise of SWL as a new nanotechnology object for the creation of thin-film nanomaterials. The studied problem is the formation of interfaces in thin-film nanomaterials. The purpose of the article is to substantiate the discovery of nonequilibrium solid wetting layers, their uniqueness and their role in the formation of the above-mentioned interfaces. This is important research for nanomaterial technologies. A review and generalization of the results of the study of the metal–silicon interface obtained under identical conditions was carried out. The review shows the detection a new type of transition state of the film under nonequilibrium conditions, a solid wetting layer, and the generalization justifies its role in the formation of the interface. Solid wetting layers are important as a new concept for the development of the theory of thin film growth, as well as a new object of nanotechnology for the production of thin-film nanomaterials

Thermal Regime of Permafrost on the Western Yamal Under Climate Warming

Climate change observed in the Arctic affects all components of the natural environment, including the state of permafrost. The purpose of this study is to quantify the response of permafrost in various landscapes to changing climatic parameters. The results of long-term field observations (1978-2021) of the thermal regime of permafrost on the Western Yamal are presented. Along with the increase in mean annual air temperatures, the mean annual ground temperature over the past 43 years has increased by 1.5-2.2°C. The maximum increase of permafrost temperature values is observed on flat and polygonal tundra, the minimum increase is typical for flooded lake basins. A decrease in the annual permafrost temperature amplitude was revealed. That is caused by a rapid increase in the air temperature of the cold period, an increase in the snow thickness and an increase in soil moisture in the active layer. The shrinking in ground temperature amplitude at a depth of 5 m is 0.5-3.6°C. A trend of reducing depth of zero annual amplitude from 12-18 m (1980) to 13-16 m (2021) has been revealed.

Utilizing shallow seismic reflection for mitigating seismic and geo-environmental hazards in the development project of Gabal Ataqa Area, Cairo–Suez District, Egypt

Nowadays, development projects are becoming so rapid in many developing countries worldwide. The study of interest focuses on Cairo–Suez District, which represents the most important location in Egypt for major infrastructure projects and urbanization expansion. Consequently, it is very important to reduce the hazards surrounding this area from natural disasters, so all information that supports geo-environmental hazards assessment is importantly needed. The Gabal Ataqa area has socioeconomic importance as it is considered the industrial zone in the national project for developing the northern part of the Gulf of Suez. The situation of Gabal Ataqa area for being rich with numerous geological structures, and its socioeconomic importance calls the need for the delineation of the subsurface structural features in this area using the appropriate method. The geological framework has recognized all Quaternary faults in the Gabal Ataqa area as they are exposed to the surface, at the same time, no seismic reflection data has been acquired in the Gabal Ataqa area. Accordingly, the shallow seismic reflection method is applied in the Gabal Ataqa area to detect the Quaternary faults that are not exposed to the surface and also to detect any subsurface features that may cause construction problems, such as water-wet sands, sabkhas, and limestone cavities. Three lines of 2D seismic profiles are acquired in the study area. After applying seismic data processing and interpretation, two Quaternary faults have been recognized in the first and third lines. The location of the first seismic line has been chosen to be between two historic earthquake events, increasing the probability that the sources causing these two events will be located on the newly recognized quaternary fault. A dim spot has been recognized in the second seismic line at a depth of 50 m, which may indicate the presence of a groundwater aquifer or wet sandstone layer. Based on these results, changing the industrial zone place to another side to be away from the area of the three seismic lines is highly recommended.

Penetration of a solid spherical particle into artificial and natural wet granular ice layers: Dynamic strength characterization

The strength of wet granular ice layers is an important quantity for modelling the behaviour of ice accretions encountered in aircraft engine icing since it determines the dynamics of the collision of ice crystals, their penetration into the layer, breakup and the characteristics of the ejected material. In the present study, impact tests of 3.18 mm nylon spheres are conducted on wet granular ice layers for a dynamic strength characterization. An experimental setup and methodology are designed to measure the crater depth for impact velocities ranging from 5 ms−1 to 90 ms−1. Experiments are conducted using both ice layers generated by ice crystal accretion on a solid substrate inside an icing wind tunnel and artificial ice layers prepared in a laboratory environment. By fitting the Poncelet penetration equation to the experimental data, two dimensionless parameters are derived that characterize the strength of the investigated ice layers in relation to the layer inertial resistance and apparent yield strength. A key finding is that strong connections between individual ice particles exist for ice layer generated in the wind tunnel, originating from re-freezing of liquid water near the particle contacts. Only by re-enforcing the ice particle connections in ice layers prepared in the laboratory, comparable strength values are obtained. The presented methodology enables measurement of ice layer strength and comparison at different facilities as well as conducting advanced experiments with realistic ice layers in a laboratory environment.

Mixtures of self-propelled particles interacting with asymmetric obstacles.

In the presence of an obstacle, active particles condensate into a surface "wetting" layer due to persistent motion. If the obstacle is asymmetric, a rectification current arises in addition to wetting. Asymmetric geometries are therefore commonly used to concentrate microorganisms like bacteria and sperms. However, most studies neglect the fact that biological active matter is diverse, composed of individuals with distinct self-propulsions. Using simulations, we study a mixture of "fast" and "slow" active Brownian disks in two dimensions interacting with large half-disk obstacles. With this prototypical obstacle geometry, we analyze how the stationary collective behavior depends on the degree of self-propulsion "diversity," defined as proportional to the difference between the self-propulsion speeds, while keeping the average self-propulsion speed fixed. A wetting layer rich in fast particles arises. The rectification current is amplified by speed diversity due to a superlinear dependence of rectification on self-propulsion speed, which arises from cooperative effects. Thus, the total rectification current cannot be obtained from an effective one-component active fluid with the same average self-propulsion speed, highlighting the importance of considering diversity in active matter.

A facile preparation of high flux NaA zeolite membranes by direct secondary growth of wet gel layer

NaA zeolite membranes were first applied in industrial organic solvent dehydration in 1999. However, issues such as poor reproducibility, low flux, and high cost of NaA zeolite membrane preparation have hindered its industrial progress. In this work, a direct secondary growth of wet gel layer method is employed. Specifically, a wet gel layer is coated to the outer surface of the seeded support, which is then placed into the Teflon-lined autoclave without additional hydrogel inside. Under the conditions of conventional secondary growth (100 °C for 4 h), high flux NaA zeolite membranes can be prepared. The pervaporation performance in the 90 wt% ethanol/water solution is tested at 75 °C, showing the flux up to 4.59 kg m−2 h−1 and the separation factor above 10,000. The controlling factors involved in the preparation of high flux NaA zeolite membranes using the direct secondary growth of wet gel layer are investigated. It is found that the introduction method of the seed layer and wet gel layer, the size of the seed, the state of the gel, and the immersion time play significant roles in the formation of zeolite membranes with superior separation performance. This method provides a new idea for the preparation of high performance, low cost and reproducible zeolite membranes with prospects for industrial application.

Effects of different irrigation methods on regional climate in North China Plain: A modeling study

Agricultural irrigation is important in boosting crop yields in especially water-stressed regions, but little is known about the distinct climatic effects induced by different irrigation methods, particularly in the North China Plain (NCP) where irrigation is applied extensively. Here we examine the climatic effects of flood (FI), sprinkler (SI) and drip irrigation (DI) over NCP during the growing season using dynamic irrigation schemes implemented into a coupled land-atmosphere model. The model generally captures the spatial distribution of surface temperature, relative humidity and precipitation. The changes in regional average surface temperature induced by FI, SI and DI are –0.43, –0.53 and –0.19 °C, respectively. The relatively larger cooling effect for SI than that for FI is associated with enhanced cloud formation. By shifting the surface energy balance, FI and SI cause a wet, cool, cloudy and shallow planetary boundary layer, while DI exhibits the smallest effect and indeed inhibits cloud formation. The increases in convective available potential energy and precipitable water induced by FI and SI enhance convective precipitation over NCP by 0.8–1.2 mm d–1. In contrast, the reduced precipitation due to surface cooling within DI leads to a warmer and drier surface from June to August, which likely increases upper-level geopotential heights and in turn suppresses precipitation in a series of climate feedbacks. The distinct hydrometeorological interactions and feedbacks arising from different irrigation methods are likely related to different irrigation rates, frequencies and approaches of water application. While DI is recognized as the most water-saving method, it also generates the least surface cooling among the three methods and is thus less effective in safeguarding grain yields against rising temperatures. Our study emphasizes the need for more sustainable and adaptive irrigation methods to ensure food security, water conservation and climate stability in the face of climate change.

The impact of abiotic and key environmental factors on barley yield

The purpose of the study is to determine the influence of agrometeorological factors (temperature, precipitation, dry weather), soil moisture, agrofon nutrition and precursor on the yield of barley in crop rotations and permanent sowing. The research is carried out from 2017 to 2022 on southern chernozems in the central zone of the Orenburg region. The scheme of the experiment consists of six options for growing barley on a fertilized and natural agrofone of a stationary experimental site for multi-fields and monocultures, laid down in 1990. The following methods of research are used in the experiments: field, thermostatic-weight method and dispersion analysis. As a result of observations, the air temperature during the growing season of barley is 20.7 ° C, precipitation – 111-112 mm, dry days – 68. The hydrothermal coefficient is 0.5 units, which characterizes the growing season as medium dry. The level of spring soil moisture in the meter layer of soil is from 97.0 to 123.8 mm in all variants of the experiment. In the second variant of the experiment, an increase in the yield of barley is observed in the aftereffect of millet and on the fertilized agrophone is 1.65 t, on the natural one – 1.51 t / ha. The yield of barley of the other variants is in the range from 1.26 to 1.61 t/ha. There is an increase in grain from mineral fertilizers by 0.03-0.27 tons for all variants of sowing barley. The best effect of atmospheric precipitation, spring reserves of soil moisture, precursors, mineral fertilizers on the yield of barley in the aftereffect of millet, peas and durum wheat in crop rotations has been established. The reasons for the decrease in the yield of permanent sowing of barley have been identified. The results of the study are of crucial importance in the development of agriculture and the production of feed grain in the steppe zone of the Southern Urals.

The effect of relative humidity on multicomponent organic vapor adsorption on composite beds with micro-fibrous entrapped activated carbon

Composite bed involves an alternative technique in which a layer of micro-fibrous entrapped composite material is added at the downstream end of a conventional fixed bed to strengthen the mass transfer process. In this study, our purpose was to compare the ability of composite beds to remove volatile organic compounds (VOCs) and Freon refrigerants with conventional fixed beds and analyse the effect of relative humidity (RH) on multicomponent organic vapor adsorption on composite beds. This would be used to guide the design of composite beds and their application in air purification. A series of micro-fibrous entrapped activated carbons (MFECs) were prepared using the wet layer paper-making/sintering technologies. The 1,1,1,2-tetrafluoroethane (R134a) and C6H6 breakthrough curves and times on composite beds were systemically evaluated under dry and wet conditions. Results show that under dry condition, due to the enhanced mass transfer, the R134a and C6H6 breakthrough times on composite beds were longer than on fixed beds. Under wet conditions, due to the water vapor competitive adsorption and the difference in organic vapor boiling point, the composite bed prolonged the C6H6 breakthrough time but weakened the R134a breakthrough time. Multicomponent competitive adsorption process (R134a/C6H6) under wet conditions was revealed and divided into six stages including Co-adsorption, H2O and R134a breakthrough, R134a desorption, R134a and H2O adsorption equilibrium, C6H6 breakthrough, and dynamic adsorption equilibrium. These findings indicated that composite beds may improve the breakthrough time of low-concentration C6H6 and lengthen the service life of conventional fixed beds at any RH, thereby displaying potential for use as an application in air purification.

Влияние погодных условий, основной обработки почвы, продуктивной влаги и питательных веществ на урожайность зерновых культур

Abstract. The aim of work – to establish the impact of weather factors, the content of productive moisture and nutrients in the soil on increasing the yield of field crops in grain-pair crop rotations. Research methods: field, thermostatic-weight, ionometric, Machigin’s. Scientific novelty. For the first time, the impact of agrometeorological conditions (2014–2021), the content of productive moisture and nutrients on the yield of grain crops after zero and flat-cut processing (25-27 cm) of soil on parts of the slope was assessed. Results. It was found that, on average, during the growing season (May – August), the air temperature (18.8 °C) and dry days (74) negatively affect the yield of barley (1.10 and 0.86 t/ha) on the upper part of the slope and amount to 55.72 and 66.55 % for flat-cut tillage compared to zero (control) – 43.88 and 55.38 % (P ≤ 0.05). Atmospheric precipitation (92.0 mm) has a positive effect on the yield of durum wheat (0.99 and 0.83 t/ha) on the middle part of the slope and amounts to 47.39 % on the flat-cut and 52.03 % without tillage (P ≤ 0.05). Spring productive moisture (105.0 and 101.0 mm) in the meter layer of soil favorably affects the yield of soft wheat (1.05 and 0.78 t/ha) on the upper part of the slope and amounts to 64.15% for flat-cut processing compared to 76.80 % control (P &lt; 0.05). The increase in the yield of soft wheat (1.42 t/ha) and barley (1.43 t/ha) depends on the influence of the content of mobile phosphorus (3.7 and 3.5 mg / 100 g) in the soil layer 0–30 cm on the lower part of the slope for flat-cut processing and amounts to 54.15 and 55.98 % (P &lt; 0.05). Thus, dry weather conditions, the content of productive moisture, nitrate nitrogen, mobile phosphorus and potassium for the remaining sowing options do not affect the increase in yield.