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The impact of the depth of selection of narrow gas oil fractions of Azeri-Chirag-Guneshli oils on the yield and quality of catalytic cracking products was studied. The impact of fractional and group hydrocarbon composition on the main directions of cracking is analyzed. 5 types of gas oil fractions selected in the range of 200-360, 200-410, 200-440, 200-460, and 200-500°C were used as feedstock for catalytic cracking. The results of catalytic cracking of narrow gas oil fractions of Azeri-Chirag-Guneshli oils indicate a nonlinear nature of the dependences on the boiling point limits. The highest total yield of light oil products was obtained by cracking gas oil fractions boiling in the range of 200-410 and 200-440°C, reaching 60.5 and 60.8%, respectively. At the same time, the main contribution to this indicator was made by the gasoline fraction (31.5-33.2%). It was based on paraffin-naphthenic hydrocarbons. The yield of the diesel fraction changed symbiotically with the increasing weight of the fractional composition of the raw material, reaching maximum values of 9.9% during the cracking of the gas oil fraction, boiling in the range of 200-500°C. Based on a comparison of the ratio of iso-butane to iso-butylene, it was concluded that the cracking of gas oil at 200-440°C was accompanied by a significant contribution of bimolecular hydrogen transfer reactions. [ABSTRACT FROM AUTHOR]

The most important component of the concept Quality-by-Design (QbD) is the provision of a scientific approach to substantiation and optimization of each critical process parameter (CPP) and identification of the link between CPPs and critical quality indicators. Wet granulation is one of the most critical stages of the technological process in GSB-106 tablet production technology. The process of optimizing the wet-granulation stage using regression analysis was considered in the present study in relation to determination of the granulation process time for a low shear force mixer. Samples of tablet masses taken at various time points from 10 to 60 min were analyzed for several indicators such as the particle-size distribution, flowability, bulk density before and after compaction, and Carr and Hausner indices. Tablets were produced from the selected model samples at various pressing forces and assessed for hardness and disintegration. The results were analyzed using regression analysis to obtain linear regression equations describing the dependence of pharmaceutical and technological characteristics on the duration of wet granulation. Critical indicators were identified. The optimum time for a given technological process was determined. Dynamic equilibrium in the granule agglomeration process was shown to occur between 30 and 40 min of mixing. The optimal duration of the technological process was set from 40 to 50 min. [ABSTRACT FROM AUTHOR]

Synthetic graphite of complex fractional composition was mixed with phenolic resin as a binder and pore-forming component. The mixtures were pressed and subsequently heat-treated to obtain porous matrices. The structural transformations of phenolic resin by heating up to 900 °C in oxygen and inert gas media were studied and the patterns of amorphization of fixed carbon formed on the walls of the pore system during carbonization were investigated. We found regularities in the changes in matrix volume density in the function of the open porosity and the average pore diameter. It is shown that, in order to obtain graphitized carbon matrices with a density of 1 g/cm3 and an open porosity of at least 50%, it is necessary to introduce no more than 20% of phenolic resin into the molding powder with an equal content of 60, 100 and 250 μm graphite fractions. This allows for high intensity and completeness of bulk silicon infiltration. [ABSTRACT FROM AUTHOR]

Bark is a large-tonnage waste in a number of wood processing technologies requiring efficient use. One of the promising areas of bark use is the production of boards without synthetic binders. Research has been conducted on the production of structural boards from Pinus sylvestris bark without a binder. The method is based on preliminary hydrodynamic activation of bark. The initial bark undergoes primary crushing in a hammer mill. After that, it is mixed with water at a concentration of 6 %. Then the resulting mass is activated in a rotary pulsation disperser, a carpet is formed from it, cold pressing is carried out, and then hot pressing. As a criterion for assessing the degree of mass activation, water-retaining capacity is adopted. The dependencies have been determined between the duration of treatment and water-retaining capacity, as well as the strength of the boards and water-retaining capacity. The latter made it possible to obtain the optimal value of the water-retaining capacity equal to 290 %. A multifactorial experiment has been conducted to develop the optimal hot pressing mode. As a result, the optimal mode for pressing the boards has been determined: temperature – 190 °C; specific process duration – 2.8 min/mm; pressing pressure – 4.4 MPa. The properties of the boards produced in this mode are: density – 980 kg/m 3 ; bending strength – 24 MPa; swelling during soaking for 24 hours – 5 %; water absorption – 9 %. After soaking and subsequent drying to a moisture content of 5 %, the boards retain 75 % of their before soaking. In this case, the geometric dimensions return to the original ones. The resulting boards can be used as a sheet finishing and structural material, in house-building (as a base for floor and roofing materials), in furniture production, especially in severe temperature and humidity conditions. The conducted research shows the possibility of producing board materials with high performance properties from pine bark without binders.

In the complex of priority directions for development of potato production in the Russian Federation, the most urgent task is to increase efficiency of using varietal resources of the best domestic breeding achievements, as well as development of modern technological schemes for production of initial, original and elite seed potatoes. Recently, many attempts have been made to improve the technology of growing potato mini-tubers, which belong to the category of starting material in seed production, in order to obtain the maximum number of tubers per unit area. The main goal of the research was to study the effect of biological agents: Albit (poly-beta-hydroxybutyric acid + magnesium sulfate + potassium phosphoric acid + potassium nitrate + carbamide), BisolbiSan (Bacillus subtilis, strain H-13 + metabolites obtained during the cultivation of the strain), Prorastin (N, P2O5, K2O, Cu, Co, Zn, humic acids, auxins, gibberellins, cytokinins), Polystine (N, P2O5, K2O, Cu, Co, Zn, fulvic acids, auxins, gibberellins, cytokinins) and aproduct based on fungal arbuscular mycorrhiza (Rhizophagus irregularis) on yield of conditioned mini-tubers of potato cv. Ariel and cv. Sadon and their average weight by fractions in protected soil conditions. The one-factor experiment was carried out in agreenhouse of spring-summer type. Potato micro-plants were grown in 5L plastic pots filled with soil Agrobalt-C. Experiment variants: 1)Control (without treatment); 2)Albit, pre-treatment + two foliar dressings; 3)BisolbiSan, pre-treatment+3foliar dressings; 4)Prorastin + Polystin, pre-treatment (Prorastin) + 2 foliar dressings (Polystin); 5)Product based on the fungal arbuscular mycorrhiza (Rhizophagus irregularis), pre-treatment of micro-plants. It was found that Prorastin and Polystin and treatment of the root system of micro-plants before planting with bioagent based on the fungal arbuscular mycorrhiza (Rhizophagus irregularis) provided the best indicators for yield of conditioned mini-tubers cv. Ariel and average weight of tubers of both cultivars.

This article presents the results of studies into the physicochemical properties of Arctic crude oil and its fractions. According to its characteristics and group composition, the Arctic shelf oil is a bituminous, high-sulfur, and low-paraffin oil with the content of light fractions less than 50 wt %. Approaches to its refining are proposed. [ABSTRACT FROM AUTHOR]

An analysis of methods for separating metal powders of different sizes for gas-thermal coating technologies was carried out. The results of research on the development of a new method for separating different fractions of powders of a given granulometric composition and an installation for their preparation are presented. An algorithm for operating an experimental installation for separating powder materials into fractions is analyzed in detail. The features of reducing the degree of fluctuation increases and the process of fluidization of material particles in the process of their separation are described. Data were obtained to determine and evaluate the relaxation of the gas flow in the proposed installation. [ABSTRACT FROM AUTHOR]

The process of blast furnace production relies heavily on the quality and composition of its charge materials, among which iron ore sinter plays a crucial role. The consistency in the fractional composition is intrinsically linked to the method employed for their fragmentation. This fragmentation, or crushing, is influenced by the type of load applied and is inherently dependent on the design and functionality of the crushing machinery utilized. Based on the mechanics of the crushing process, a mathematical model has been developed to describe the interaction between the sprocket teeth and the material being crushed. This model aids in determining the optimal conditions that facilitate the material entry into the active crushing zone of a toothed rotary crusher. Through this analysis, it becomes evident that rotors outfitted with chevron and spiral-configured sprocket teeth significantly outperform those with a linear arrangement. Experimental investigations into the agglomerate crushing process have shed light on the outcomes of different deformation methods. When subjected to compression deformation, it was observed that the resulting material contained 17.2% of fines smaller than 5 mm and a -10 mm fraction amount to 31.1%. Conversely, a more controlled process emerges during stretching in bending, which remarkably reduces the −10 mm fraction to only 1.6%. Building upon these insights, a modernized toothed rotary crusher featuring a nonlinear rotor was developed and implemented in the sintering production of Branch No. 1 AISW of SMMC. The introduction of this advanced crusher led to notable improvements in the screening process of hot sinter. After employing this upgraded machinery, there was a 2–4% increase in the amount of return material alongside a significant 6–7% reduction in screenings during the classification stage on the conveyor path for supplying blast furnace No. 1 with charge materials. Moreover, this optimization ensured the elimination of oversized pieces, specifically those exceeding 80 mm. [ABSTRACT FROM AUTHOR]

The aim of this work is to study the transformation of priority pollutants compounds, i.e., of Pb and Cd in soils with different buffer capacity and pollution level. The object of study is southern chernozem (Haplic Chernozem), calcareous, heavy loamy, collected in a virgin site in the Rostov-on-Don region, the layer 0–20 cm. Lead and Cd nitrates were added separately in doses of 2, 5, 10 approximately permissible concentration (APC) of metal (130 mg/kg for Pb and 2 mg/kg for Cd) into soil samples of the model experiment containing quartz sand in the ratios 1 : 0.25, 1 : 0.5, 1 : 0.75 of the soil mass. The buffer capacity of soils in relation to Pb and Cd was assessed according to the method of V.B. Il'in (1995), based on the content of physical clay, organic matter, carbonates, R2O3, and pH. The ability of soils to firmly bind Pb and Cd was studied proceeding from the results of fractional group composition of metals using a combined fractionation scheme. In unpolluted heavy loamy Haplic Chernozem, the buffer capacity of soils in relation to Pb and Cd is high and is ensured by strong retention of metals by silicates and clay minerals (50–64% of the total fractions). Dilution of the initial soil with quartz sand reduces its buffer capacity from high to medium and low. When soil is contaminated, organic matter plays the most active role in the interaction with Pb; and Fe–Mn oxides are most important in the case of Cd. With a decrease in soil buffer capacity and growing pollution, the group of loosely bound compounds increases by 6–54%, mainly due to complex compounds in the case of Pb, and due to exchangeable and specifically sorbed by Fe–Mn oxides in the case of Cd. At the application dose of 10 APC Pb, the soil buffer capacity changes from low to very low. The data obtained are important for predicting and normalizing pollution of soils with different physicochemical properties. [ABSTRACT FROM AUTHOR]

The catalytic vacuum gas oil oxycracking process in the presence of zeolite-containing OMNIKAT-210P catalyst was studied. It was observed that temperature and degree of oxidation have the same effect on the degree of feedstock conversion and the yield of reaction products, whereas temperature and contact time are antithetical. Introduction of oxygen was found to facilitate diesel fraction and hydrocarbon gas formation. Determination of physicochemical characteristics of narrow fractions made it possible to assess the quality of the potential commercial straight-run products of vacuum gas oil oxycracking, depending on the technological conditions of the process. [ABSTRACT FROM AUTHOR]

Since spelt grain is one of the most promising non-conventional types of plant material for healthy food products, it is important to investigate environmentally friendly technologies for post-harvest processing of this crop. The purpose of this study was to determine the physical changes in spelt wheat grain under the influence of microwave electromagnetic radiation. The study presented the results of research on how the electromagnetic field of ultra-high frequencies and the duration of processing affect the quality characteristics of spelt grain of the Holikovska wheat variety harvested in Cherkasy region in 2020 and 2021. During the experimental study, physical methods of grain quality research were used following the developed and existing methods and industry standards. The complex structural changes in spelt grains during their treatment with an ultra-high frequency electromagnetic field with an increase in grain size, shape, and volume were investigated. Analysis found that the grain fractional composition changed towards reducing the passage depending on the processing time by 1.5-4.0 times. It was found that the treatment of spelt grain with high-frequency waves for 20-180 s reduces grain moisture content by 2-36% compared to the control, with a significant decrease after the first minute of exposure. Moreover, during the first minute of intensive grain heating, the grain temperature increased, while during the next two minutes, the intensity of grain heating decreased by 1.5-3 times. It was also proved that irradiation with ultra-high frequencies decreased the number of vitreous grains, while the number of floury grains, on the contrary, increased. The analysis also found that the vitreousity of treated spelt wheat grain by electromagnetic waves of ultra-high frequency decreases by 1.3-1.5 times during the last 2-3 minutes of treatment. The developed recommendations for the use of ultra-high frequency electromagnetic waves in the technological processes of storage and processing of spelt grain can be used by enterprises to intensify the production of environmentally friendly products

Proteins of the collagen family were identified in the dermal emulsion of a freshwater fish, the African clary catfish (Clarias gariepinus). Acumulative assessment of their physicochemical properties gave reason to consider the emulsion obtained using the developed method as a source of functional biopolymers, particularly collagen proteins. The fractional composition, charge state, molecular mass, and the ability for hydrolysis by Clostridium histolytica collagenase were experimentally determined. Evaluation of the amino-acid composition allowed the analogy and features of collagen proteins of animal and fish origin to be identified. The studied emulsions were shown to contain negatively charged proteins with molecular masses >100 kDa, the fractions of which contained predominantly collagen. The results supported the assumption that a significant part of the hydrobiont collagen was type I collagen, which made it possible to consider them in the future as a basis for various substances and served as a starting point for understanding the physicochemical functioning essentials and assessing the possibility of using them in pharmaceutical technologies. [ABSTRACT FROM AUTHOR]

Background: The background of this research lies in the pivotal role of protein breakdown during the mashing process for producing high-quality beer. Abnormal protein degradation can adversely impact beer properties and stability. This study explores the effects of different heat treatment temperatures on unmalted barley, aiming to enhance our understanding of how such treatments influence the fractional nitrogen composition of beer wort, thus contributing to improved brewing practices and product quality. Methods: The methodology includes complex research steps, including malt preparation, mash production, and a thorough analysis of nitrogen fractions, which allows for a detailed study of the dynamics of proteolysis during beer mashing. Results: In the obtained results, evaluating the amine nitrogen content in wort through chemical analysis unveils a consistent amine nitrogen level when thermal treatment of unmalted mash occurs between 100-138°C. Beyond this range, as the processing temperature of unmalted mash increases, there is a subsequent decrease in amine nitrogen content. Despite the efficient hydrolytic cleavage of starch in unmalted raw material due to elevated temperature treatment, the nitrogen content of the beer wort remains largely unaffected. Conclusion: The authors conclude that increasing the heat treatment temperature of unmalted barley has a significant impact on the total soluble nitrogen content in the resulting beer wort. This increase is mainly attributed to the high-molecular-weight nitrogenous substances of fraction A, showcasing the potential for controlled proteolysis. Furthermore, the study suggests that achieving optimal proteolysis by employing malt with high proteolytic activity and conducting proteolysis of unmalted barley proteins prior to heat treatment enhances the overall brewing process. [ABSTRACT FROM AUTHOR]

Diesel fuel is the main fuel for transport and power generation for remote areas, especially the Arctic. For these territories, it is important to produce low-freezing fuel grades. The most effective way to improve the low-temperature properties of diesel fuels (cloud point, pour point, and cold filter plugging point) is the use of depressant additives. Existing research shows that the depressant additives' effectiveness is influenced by many factors. The most important factors are diesel fuel composition, additive concentration, and the temperature of additive introduction into the fuel (adding temperature). The purpose of this work is to find ways to increase the efficiency of depressant additives for the production of low-freezing diesel fuels by choosing the most effective additive concentration and adding temperature for fuels of various compositions. During the work, low-temperature properties were determined and the effectiveness of three depressant additives was assessed on four samples of diesel fuel at four concentrations (0.5, 1.0, 2.0, and 5.0 c.u., where c.u. (conditional unit) is the concentration recommended by the manufacturer of the additives). In addition, low-temperature properties for blends of six depressant additives and two samples of diesel fuel at five adding temperatures (15, 25, 35, 45, and 55 °C) were determined. In this work, in contrast to existing works, it was established for the first time that the composition of the fuel affects not only the depressant additives effectiveness, but also the dependence of the additive effectiveness on the concentration in which it is used. It is shown that the higher the content of paraffins in the composition of the diesel fuel, the less the depressant additive's effectiveness in relation to cold filter plugging point depends on the concentration and the more the depressant additive's effectiveness in relation to the power point depends on the concentration. An inverse relationship was revealed for the content of aromatic hydrocarbons in diesel fuel. It was also found for the first time that an increase in the adding temperature of depressant additives up to 35–55 °C enhances the effectiveness of their action in relation to the cold filter plugging point (maximum at 6–7 °C). It is shown that the greater additive effect on the cold filter plugging point of the diesel fuel, the more strongly the depressant effectiveness depends on the adding temperature. The work provides recommendations for obtaining the most low-freezing classes of fuel based on the samples considered. The regularities identified in the work will make it possible, depending on the composition of the fuel, to select the optimal concentration of the additive and the temperature of its adding, which will increase the efficiency of the additives, as well as the volume of low-freezing grades of diesel fuel production. [ABSTRACT FROM AUTHOR]

The kinetic features of the decomposition of fuel pellets formed from birch phloem and its composites with the addition of oil-containing waste (OCW) were studied by methods of thermogravimetric analysis carried out in various atmospheric conditions. The characteristic temperature ranges of thermal decomposition of the materials from which pellets are formed were identified. The rates of mass loss and activation energy at the main stages of thermal decomposition were evaluated. And the combustion indices of composite compositions were determined to identify the possibility of using such compositions as alternative fuels. By evaluating activation energies for each stage of sample decomposition, the limiting influence of certain stages of the thermal destruction process was established. [ABSTRACT FROM AUTHOR]

The properties of coke depend on numerous factors, including the density of the compacted coal cake. The influence of batch compacting (stamp charging) on the properties of metallurgical coke produced in coke shop 3 at Alchevsk Metallurgical Complex, SMMC, is studied in the present work. The distribution of the batch density over the height is determined with different compacting conditions in the compacting–charging–discharge machine. In different stamping conditions, the density of the charge gradually decreases with increase in height; the difference may reach 13%. The granulometric composition and strength of the metallurgical coke and the yield of volatiles are determined in different compacting conditions and at different sampling heights. With increase in batch density from 0.87 to 1.08 g/cm3, the content of the 40–60 mm fraction increases by 10%; the yield of volatiles is decreased by a factor of 1.6; and the strength remains unchanged. In the upper part of the coke cake, where the initial batch density is lower, the coke quality is significantly worse: the content of the 40–60 mm fraction falls by 33.3%; the yield of volatiles is increased by a factor of 1.6; and the coke strength M25 falls by 2.9%. Topics for further research are suggested, with a view to improving the quality of the metallurgical coke produced in coke shop 3 at Alchevsk Metallurgical Complex. [ABSTRACT FROM AUTHOR]

We demonstrate that an increase in the area of fused sections relative to the total area of the construction platform deteriorates the quality of the recycled powder owing to accumulating oxidized emissions. The quality of synthesized material deteriorates both as a result of cross-contamination caused by oxide particles (emissions) and metal condensate penetrating the construction zone and owing to the use of recycled powder. The different mechanisms of contamination are established for the metal synthesized at high filling densities of the construction platform. A dense arrangement of samples and dominating exposure of the base metal result in better segregation of chromium oxides at the grain interfaces. A significant decrease in strength and ductility is obtained at a temperature of 1000°C after the second run. These parameters remain practically the same during further testing. The long-term strength slightly increases in the samples obtained in the second and the third run. The heat resistance of synthesized VZh159 alloy depends very little on the use of recycled powder. [ABSTRACT FROM AUTHOR]

The growing demand for biomass is forcing attention toward alternative resources, including agricultural by-products such as fiber hemp (Cannabis sativa L.). Growing hemp for seed produces about 10 tons of dry matter by-products per hectare. Processing-conversion technologies used in practice change the properties of primary raw materials, give them higher added value, and prepare them for various needs. In addition to economic benefits, biochar contributes to carbon sequestration and increases the sustainability of agricultural production. This study evaluated the effect of thermochemical treatment in an oxygen-free environment on some physicochemical properties of the fiber hemp by-products of the Felina 32 variety. At a heating temperature of 700 °C, the biomass yield of biochar from stems was 28.4 ± 0.5% and from seed husks was 30.6 ± 0.6%. At that time, the carbon concentration in fiber hemp stems biochar increased 1.82 times, from 45.0 ± 2.26% to 81.9 ± 8.46%, and in seed husk biochar by 1.20 times, from 56.5 ± 11, 6% to 67.9 ± 7.47%. Furthermore, the changes in the fractional composition, density, calorific value, ash content, and ash melting characteristics that occurred during the conversion of primary raw material of fiber hemp into biochar were evaluated.

The influence of the type (grits from an ingot, a quick-cooled plate) and size of the fraction of a modifier and the REM content on the structural of camshaft castings made of ChVG40 vermicular graphite iron (VGI) are studied. [ABSTRACT FROM AUTHOR]

Specific features of the organic matter transformation in peat eutrophic soils (Hypereutric Sapric Histosols) and peaty gleezems (Eutric Histic Gleysols) 20 years after a forest–peat fire are discussed within the ecological direction of studying humus using traditional methods and terms. The study object is represented by a green-moss–hypnum spruce forest (Picea obovata Ledeb.) on the eastern slope of the Kuznetsk Alatau (at the altitude of 622 m above sea level). The composition of organic matter of pyrogenic soils (0–30 cm) is characterized by high variability (the variation coefficient is 12–92%). According to the factor analysis, the total variance is related to a combination of humic substances (76%) and to polysaccharides (24%). Cluster analysis enables us to identify two groups of objects, and their statistical reliability is confirmed by the discriminant analysis. Soil clusters reflect the peculiarities of pyrogenic processes: underground focal smoldering below the point of ignition and open intensive and moderate fire. Carbon content decreases to 26.5 and 13.4%, respectively, relative to the background (41% in peats not affected by fire). The formation of humification products is almost equal: (∑HA + ∑FA) is 55.4 and 53.7%, mainly due to fulvic acids (CHA/CFA = 0.2–0.6). The peculiarity of the thermal effect is mainly seen at the fractional level. The specificity of underground smoldering consists of an increased formation of fulvic acids of the first fraction free and loosely bound to R2O3. An open fire is accompanied by the predominating formation of humic and fulvic acids bonded to calcium. According to standardized coefficients of canonical analysis, the first and second fractions of humic and fulvic acids make the greatest cumulative contribution to cluster discrimination, and the maximal personal weight is related to HA-2, FA-1, and FA-2. Based on previously obtained data on the group composition of buried peats and the important role of anaerobiosis in the formation of humic acids, which better correspond to the restored substance when compared to fulvic acids, it may be assumed that peat formation, continuing in the fire area, can cause the transformation of fulvate humus into fulvate-humate and/or humate one. In the case of burial of a pyrogenic peat layer 0–30 cm in thickness, the transformation may occur over about 270 years, taking into account the rate of linear peat growth in spruce forests of the Kuznetsk Alatau: 1.12 mm/year. The research results confirm that the traditional division of humic acids into fractions is reasonable. [ABSTRACT FROM AUTHOR]

This study focuses on the impact of pre-planting irradiation of seed potatoes on the phenophases of the root crop and proliferation of fungus Rhizoctonia solani on the new crop tubers. A two-year monitoring of seed potatoes after irradiation shows that treatment of tubers with 30–40 Gy decreases the spread of fungal infection on the surface of the tubers. It was found that low-energy electrons used in the experiment are the most effective irradiation treatment since they penetrate in the upper layers of potato tubers affected by the fungus. [ABSTRACT FROM AUTHOR]

It is not uncommon that subways count as densely populated areas, so air quality standards, including fine dust concentration, have been established for them. As passengers and subway staff are exposed to potentially harmful airborne particles, addressing this issue is vital to ensuring a safe and healthy environment on the subway. To reduce the dust concentration in subway systems, the authors propose installing filters to capture dust in ventilation failures between subway tunnels near metro stations. A novel aspect of the proposed method is the fact that airflow will be moved through filters by using the piston action of trains passing through the tunnels. The result of this research provides empirical evidence regarding dust content and mass concentrations of PM2.5 and PM10 in subway environments. While some existing literature discusses air quality in subways, the inclusion of specific measurements and data from the experiment strengthens the understanding of the severity of dust-related air quality issues in such environments. The data for this study were collected in the Almaty subway (Republic of Kazakhstan) at four stations: Raiymbek Batyr, Almaty, Baikonur and Alatau. Measuring points were located on passenger platforms, in the halls and at the entrances to the station. The lab scale tests determined the percentage of particles by their diameters relative to the total volume of dust, the percentage of dust particles smaller than a certain diameter, the percentage of various metal oxides and the average dust density. A preliminary energy assessment has been done on the proposed method of air purification from dust. With a frequency of 24 pairs of trains per hour, the energy savings per ventilation failure will be 240.170 kWh. [ABSTRACT FROM AUTHOR]

Smokeless tobacco products are products that do not require a pyrolysis process and / or the production of tobacco aerosol (smoke) at the time of use. In the absence of data on the toxicological risks of smokeless tobacco, their consumption is potentially on the rise. The variety of non-smoking tobacco products creates certain problems in identifying chewing tobacco and sucking tobacco (banned for sale in the Russian Federation) as products that are identical in terms of physiological effects, method of consumption, and component composition. A methodology has been developed for a comprehensive assessment of non-smoking products, including the determination of consumer properties and technological indicators by instrumental methods, as well as the determination of the level of toxic components (nicotine, TSNA, B(a)P). The difference between the types of smokeless tobacco is mainly in the granulometric composition of the product: snus – finely ground tobacco, chewing tobacco – snatches of tobacco with a removed middle vein. Identification indicators have been determined: the presence of raw tobacco, the size of its particles and the number of large fragments in the finished product. The presence of raw tobacco can be determined by optical microscopy and/or luminescent analysis, and the quantitative content can be determined by sieve analysis. The quantitative content of the coarse fraction in chewing tobacco (not less than 15 %) is the main indicator of the product. The use of the fractionation method makes it possible to differentiate between sucking and chewing tobacco. A «Method for determining the fractional composition of non-smoking tobacco products for oral consumption by the method of sieve analysis» was developed (Certificate No. 022-01.00281-2013-2022). To certify the methodology, a set of studies was carried out, the data were obtained as a result of five parallel measurements by three performers for each sample. The technique is registered in the State Register of Measuring Instruments (FR.1.31.2022.43935 of 09/02/2022). Technological indicators of SLT samples were established: humidity (11,4-53,3) %, pH level 5,7-9,7, coarse fraction content (0,4-56,9) %, dust fraction content (0,2-76,3) %. The results of identification of commercial samples of a segmental product are presented.

The growing demand for biomass is forcing attention toward alternative resources, including agricultural by-products such as fiber hemp (Cannabis sativa L.). Growing hemp for seed produces about 10 tons of dry matter by-products per hectare. Processing-conversion technologies used in practice change the properties of primary raw materials, give them higher added value, and prepare them for various needs. In addition to economic benefits, biochar contributes to carbon sequestration and increases the sustainability of agricultural production. This study evaluated the effect of thermochemical treatment in an oxygen-free environment on some physicochemical properties of the fiber hemp by-products of the Felina 32 variety. At a heating temperature of 700 °C, the biomass yield of biochar from stems was 28.4 ± 0.5% and from seed husks was 30.6 ± 0.6%. At that time, the carbon concentration in fiber hemp stems biochar increased 1.82 times, from 45.0 ± 2.26% to 81.9 ± 8.46%, and in seed husk biochar by 1.20 times, from 56.5 ± 11, 6% to 67.9 ± 7.47%. Furthermore, the changes in the fractional composition, density, calorific value, ash content, and ash melting characteristics that occurred during the conversion of primary raw material of fiber hemp into biochar were evaluated. [ABSTRACT FROM AUTHOR]

The particle size distribution of woodworking residues influences the quality of the biofuels made of these materials. Hence, it is essential to investigate the fractional composition of raw materials for pellet production. Tested materials originated from ten parquet manufacturing facilities located in western Poland. The research material consisted of uncontaminated oak (Quercus spp.) wood particles. The tested material had a moisture content ranging from 8.8% to 11.4% and a density of 210.7 ± 1.79 kg/m3. A sieve analysis method segregated the tested material into four distinct size fractions (<1.0 mm, 1.0-2.5 mm, 2.5-5.0 mm, and >5 mm). The average mass shares in these fractions were 53.72 ±0.51%, 35.14 ±0.27%, 9.59 ±0.36%, and 1.55% ±0.11%, respectively. The particle size distributions of wood particles generated in all the facilities demonstrate remarkable similarity. No substantial differences were observed in terms of tilt angle and calorific value. Factors such as variations in raw material species, geographical origins, density, humidity, and technological processes appear to have minimal influence on the sieve-size distributions of the generated sawdust. All these solid wood processing residues can undergo processing into high-quality solid biofuel production. [ABSTRACT FROM AUTHOR]

This paper presents the outcomes derived from an environmental assessment of microplastic pollution resulting from solid waste landfills in the Akmola Region, situated in North Kazakhstan. This research represents a pioneering investigation conducted on microplastics within this specific region. This study encompasses a comprehensive examination of plastic waste disposal sites across the Akmola region, with a particular emphasis on evaluating the status of the municipal solid waste management system. To characterize the plastic content within the waste present at the landfill sites, quantitative techniques were employed. Through experimental means, the composition and fractionation of plastics within the municipal solid waste (MSW) at the landfills were determined. These data were subjected to a comparative analysis, aligning them with official statistics and previously published scientific data from both Kazakhstan and other regions globally. The methodologies employed focused on the "soft" removal of organic substances through the use of oxidants which do not damage plastics, and were tested using a water-bath therapeutic treatment. Furthermore, an analysis of soil samples taken from the landfills unveiled the ultimate retention of microplastic particles, attributed to leachate and rainwater runoff. Extracts were obtained from the subsoil samples using a density-based separation process, involving a three-step extraction followed by subsequent filtration of the resulting supernatants. In addition, the soil samples underwent examination through dry-phase particle fractional separation. The particles were meticulously enumerated and classified, and their dimensions were measured employing microscopic techniques coupled with photographic documentation. The outcomes stemming from these diverse tests will serve as fundamental input for the forthcoming numerical modeling endeavor, which aims to simulate the behavior of microplastics within both soil and water. This endeavor represents a continuation of the research project, the preliminary findings of which are expounded upon in this paper. [ABSTRACT FROM AUTHOR]

Abstract This paper addressed the effect of copper acetate on the combustion characteristics of anthracite depending on the fractional composition of fuel and additive introduction method. Anthracite was impregnated with 5 wt% of Cu(CH3COO)2 by mechanical mixing and incipient wetness impregnation. Four anthracite samples of different fraction with d

The soil-forming process is closely related to the accumulation and circulation of organic substances, which are a source of nutrients for plants released during the mineralisation of humus, so research on determining the qualitative composition of humus is relevant. In this regard, the purpose of this paper is to determine humic and fulvic acids in typical chernozem, depending on the fertiliser system. The leading approaches to solving this problem are conducting field and laboratory studies to determine the quality indicators of humus and dispersion methods to establish the accuracy and reliability of experimental data. Based on the conducted studies, it was observed that the application of an organo-mineral fertiliser system leads to an increase in the content of humic acids, while the insoluble residue shows an increase in carbon content. The utilisation of organo-mineral fertilisers resulted in a reduction in the excessive accumulation of non-humified organic substances. Additionally, the soils in these areas exhibited a higher level of organic substance humification. The combination of organic matter at a rate of 11.5 tonnes per hectare (8 tonnes of manure and 3.5 tonnes of by-products) and mineral fertilizer N27P38K45 in a crop rotation resulted in an increasing trend of the buffering capacity of typical chernozem soil. In this scenario, there was an increase in absorption capacity at the end of the second rotation for grain-legume crop rotation by 6.05 mg/equiv per 100 g, specialised grain-legume rotation by 3.9 mg/equiv per 100 g, and legume rotation by 3.06 mg/equiv per 100 g of soil compared to the beginning of the first rotation. The use of organo-mineral fertilisers increases the third fraction of fulvic acids in specialised grain-legume rotation, which affects the ratio of humic acids to fulvic acids in favour of the humic type of humus formation. The ratio of humic acids to fulvic acids in the grain-planting crop rotation in the organo-mineral system was 2.84 at the end of the second rotation, and 2.24 at the beginning of the first rotation. The research materials are of practical importance for farmers when analysing the fractional-group composition of typical chernozem humus

Studies of the physicochemical properties of traditional gasoline (G), innovative gasoline (IG) and high-quality gasoline (HQG) have been carried out. The purpose of this work was to analyze the physicochemical properties of innovative, high-quality grades of gasoline, to compare the performance of these fuels with those of conventional fuel that does not contain substances that improve the operational and environmental qualities. The research of the properties of gasolines was carried out using an automatic apparatus for distillation of petroleum products ARNS-1E, indicator (octanometer) OKTAN-IM, gas analyzer INFRACAR 5M3T, single-cylinder, 4-stroke, overhead valve engine (Biggs Stratton). It has been established that the density of gasolines, the final boiling point, the residue in the flask and the acidity correspond to the GOST standards. A six-month storage period for fuel samples does not affect the parameters of the fuel, its physical and chemical stability. It is shown that substances that improve the properties of innovative and high-quality fuels do not affect the result of measuring the octane number of gasoline. It has been established that the chemical stability of improved grades of gasoline is higher than that of traditional fuel. It is shown that innovative and high-quality gasoline is superior to gasolines that do not contain combustion-improving substances in terms of combustion efficiency. A similar conclusion was made for nitrogen oxides, the content of which is associated with the presence in gasoline of components that increase the temperature of gases that occur in the combustion chamber of the power unit.

The condition for stable fixation of a collector on the surface of diamonds and their flotation is the use of collectors of the optimal fractional composition and the choice of the optimum temperature regime of the process. To determine the parameters of the diamond flotation regime, the regularities of the phase transitions of asphaltene-tar fractions at increasing temperature and diluting F-5 with technical diesel fraction were established. It was demonstrated that increasing the collector temperature leads to the transfer of asphaltenetar fractions to a dissolved and finely dispersed state. To an even greater extent, dissolving asphaltene-tar fractions is facilitated by the addition of medium- and low-molecular weight fractions of oil, for instance, a technical diesel fraction. It was revealed that the KM-10, KM-14, and KM-18 reagents, being compounds of F-5 fuel oil with technical diesel fraction (10–18 % DF), were characterized by optimal viscosity and ability to displace aqueous phase from a diamond surface, thus ensuring stable hydrophobization and high floatability of diamonds. The optimal temperature regime has been selected, which involved maintaining the temperature at the stage of conditioning with the collector at +30–40 °С, at which the maximum selective fixation of compound collectors on the diamond surface, characterized by the value of the limiting wetting angle, was achieved. The flotation tests have confirmed that the best results are achieved at a temperature of +30–40 °С at the conditioning stage and +14–24 °С at the flotation stage. At +24 °С, the best results were obtained for the relatively less diluted KM-10 and KM-14 fuel oils obtained by diluting F-5 fuel oil with a technical diesel fraction at the diluent volume fractions of 10 and 14 %. The diamond recovery achieved in the flotation tests was 3.8–4.5 % higher than when using the traditional collector, F-5 fuel oil. At +14 °С, the highly diluted fuel oil, KM-18 with a volume fraction of 18 % of the technical diesel fraction, demonstrated better collecting abilities. The optimal compositions of the collector and the regimes of feed preparation and flotation were tested at a foam separation unit. The tests showed that it is possible to increase diamond recovery into concentrate by 2.3–4.5 %. The recommendations are provided on the use of thermal conditioning in the foam separation cycle and maintaining the conditioning medium temperature at +30–40 °С and the foam separation temperature at +14–24 °С.

Coal tar pitch is important as a binder in the production of construction materials and as the raw material in the production of pitch coke. It is widely used, under the name of electrode pitch, as a binder in the production of electrodes and anode mass. Various modifications improve the characteristics of electrode pitch. In the present work, the practicality of modification by low-temperature thermal oxidation (up to 300°C) is considered. Specifically, experiments are conducted on the thermal oxidation of Altai Koks electrode pitch. The apparatus employed consists of a reactor, a compressor, and a heating system. The softening point, fractional composition, and yield of the oxidation products are determined. Low-temperature thermal oxidation permits the production of higher-quality electrode pitch. The duration of low-temperature thermal oxidation and the maximum temperature corresponding to increase in the softening point of the pitch are established. This outcome of oxidation is of great interest. The experiments show that the content of the α1 fraction does not increase in the low-temperature thermal oxidation of electrode pitch. The increase in softening point is associated with increase in the α2 fraction during oxidation. [ABSTRACT FROM AUTHOR]

Diesel fuel is the main fuel for transport and power generation for remote areas, especially the Arctic. For these territories, it is important to produce low-freezing fuel grades. The most effective way to improve the low-temperature properties of diesel fuels (cloud point, pour point, and cold filter plugging point) is the use of depressant additives. Existing research shows that the depressant additives’ effectiveness is influenced by many factors. The most important factors are diesel fuel composition, additive concentration, and the temperature of additive introduction into the fuel (adding temperature). The purpose of this work is to find ways to increase the efficiency of depressant additives for the production of low-freezing diesel fuels by choosing the most effective additive concentration and adding temperature for fuels of various compositions. During the work, low-temperature properties were determined and the effectiveness of three depressant additives was assessed on four samples of diesel fuel at four concentrations (0.5, 1.0, 2.0, and 5.0 c.u., where c.u. (conditional unit) is the concentration recommended by the manufacturer of the additives). In addition, low-temperature properties for blends of six depressant additives and two samples of diesel fuel at five adding temperatures (15, 25, 35, 45, and 55 °C) were determined. In this work, in contrast to existing works, it was established for the first time that the composition of the fuel affects not only the depressant additives effectiveness, but also the dependence of the additive effectiveness on the concentration in which it is used. It is shown that the higher the content of paraffins in the composition of the diesel fuel, the less the depressant additive’s effectiveness in relation to cold filter plugging point depends on the concentration and the more the depressant additive’s effectiveness in relation to the power point depends on the concentration. An inverse relationship was revealed for the content of aromatic hydrocarbons in diesel fuel. It was also found for the first time that an increase in the adding temperature of depressant additives up to 35–55 °C enhances the effectiveness of their action in relation to the cold filter plugging point (maximum at 6–7 °C). It is shown that the greater additive effect on the cold filter plugging point of the diesel fuel, the more strongly the depressant effectiveness depends on the adding temperature. The work provides recommendations for obtaining the most low-freezing classes of fuel based on the samples considered. The regularities identified in the work will make it possible, depending on the composition of the fuel, to select the optimal concentration of the additive and the temperature of its adding, which will increase the efficiency of the additives, as well as the volume of low-freezing grades of diesel fuel production.

This paper addressed the effect of copper acetate on the combustion characteristics of anthracite depending on the fractional composition of fuel and additive introduction method. Anthracite was impregnated with 5 wt% of Cu(CH3COO)2 by mechanical mixing and incipient wetness impregnation. Four anthracite samples of different fraction with d < 0.1 mm, d = 0.1–0.5 mm, d = 0.5–1.0 mm, and d = 1.0–2.0 mm were compared. According to EDX mapping, incipient wetness impregnation provides a higher dispersion of the additive and its uniform distribution in the sample. The ignition and combustion characteristics of the modified anthracite samples were studied by thermal analysis and high-speed video recording of the processes in a combustion chamber (at heating medium temperature of 800 °C). It was found that copper acetate increases anthracite reactivity, which was evidenced by decreased onset temperature of combustion (ΔTi) by 35–190 °C and reduced ignition delay time (Δτi) by 2.1–5.4 s. Copper acetate reduces fuel underburning (on average by 70%) in the ash residue of anthracite and decreases the amount of CO and NOx in gas-phase products (on average by 18.5% and 20.8%, respectively). The mechanism for activation of anthracite combustion by copper acetate is proposed. [ABSTRACT FROM AUTHOR]

The cracking of oil shale from the Kashpir deposit was studied at various temperatures (425, 450, and 475°C) and process durations (40, 60, 80, and 100 min.). It was shown that the highest yields of liquid products and oils in their composition were achieved at a cracking temperature of 450°C and a duration of 100 min. An increase in the temperature and duration of cracking led to an increase in the concentration of С1–С5 hydrocarbons in the gaseous products by a factor of 2–5. Oils isolated from the liquid products of oil shale cracking consisted of 30–45% polycyclic aromatic hydrocarbons. It was established that an increase in the temperature and duration of cracking led to an increase in the concentration of IBP–360°C fractions in the composition of liquid products. [ABSTRACT FROM AUTHOR]

It is not uncommon that subways count as densely populated areas, so air quality standards, including fine dust concentration, have been established for them. As passengers and subway staff are exposed to potentially harmful airborne particles, addressing this issue is vital to ensuring a safe and healthy environment on the subway. To reduce the dust concentration in subway systems, the authors propose installing filters to capture dust in ventilation failures between subway tunnels near metro stations. A novel aspect of the proposed method is the fact that airflow will be moved through filters by using the piston action of trains passing through the tunnels. The result of this research provides empirical evidence regarding dust content and mass concentrations of PM2.5 and PM10 in subway environments. While some existing literature discusses air quality in subways, the inclusion of specific measurements and data from the experiment strengthens the understanding of the severity of dust-related air quality issues in such environments. The data for this study were collected in the Almaty subway (Republic of Kazakhstan) at four stations: Raiymbek Batyr, Almaty, Baikonur and Alatau. Measuring points were located on passenger platforms, in the halls and at the entrances to the station. The lab scale tests determined the percentage of particles by their diameters relative to the total volume of dust, the percentage of dust particles smaller than a certain diameter, the percentage of various metal oxides and the average dust density. A preliminary energy assessment has been done on the proposed method of air purification from dust. With a frequency of 24 pairs of trains per hour, the energy savings per ventilation failure will be 240.170 kWh.

In recent years, the use of all types of fertilizers has sharply decreased, which negatively affected the state of the agroecosystem, its stability and constancy, therefore, it is extremely important to replenish nutrients, including microelements, to maintain the stability of yields. The increasing attention of scientists and industrialists deserves the question of the use of micronutrient fertilizers in the plant nutrition system, as an important element of the technology of growing crops. It is especially important to study the various forms, types and timing of their introduction. The article presents the research results for 2019-2021 according to the effect of microfertilizer Oracle multicomplex (1.5 l/ha) applied foliarly during the development phases of plants of the mid-early hybrid Orzhitsa 237 MB (VVSN 13-15, VVSN 16-18, VVSN 59) against the background of mineral nutrition – N150P90K90. It has been established that on gray forest surface-gley soils of the Western Forest-Steppe zone, a high grain yield of the mid-early corn hybrid (FAO 200-299) of the Orzhitsa 237 MV ripeness group was provided both by favorable weather conditions and by the influence of the Oracle multicomplex. Foliar application of the Oracle multicomplex microfertilizer in the phase BBCH 13-15 (3-5 leaves) increased the yield increase versus control (without micronutrient fertilization) by 0.82 t/ha, by meeting the needs of plants of this period in available forms of phosphorus, nitrogen, zinc, when panicle axes were laid on the tops of the shoots, and lateral apical meristems (future cobs) formed in the leaf axils. The highest yield by 1.19 t/ha was obtained with foliar application of micronutrient fertilizer in the phase of 6-8 leaves (VVSN 16-18). In this phase, panicle flowers, pollen grains in the stamens, the number of ears and grains in a row were laid, therefore, the content of S, Ca, Mg, Mn, Zn in the fertilizer positively influenced the formation of the reproductive organs of maize plants. Under the influence of micronutrient fertility introduced into the phase of full panic appearance (VVSN 59), blooming and pollution of maize effectively taken place, which ensured an increase in grain yield – 1.27 t/ha. The difference in this indicator between the VVSN 16-18 and VVSN 59 phases was unreliable (0.09 t/ha). Balanced nutrition of plants with macroelements (N150P90K90 with a gradual introduction of nitrogen) and micro – Mn, Cu, Zn, Fe, Co, S, Mo contributed to the formation of a 55-59 g higher weight of 1000 grains. The total yield of the coarse and medium grain fractions was 91.5-92.1%, the fine one decreased by 30.6%

The paper provides an overview of Russian and foreign articles devoted to the study of the tree litter production and decomposition in forest ecosystems subjected to natural and anthropogenic factors. The spatial variability (below crown and between crown spaces) and the seasonal features of the tree litter production, its chemical composition, and decomposition processes are poorly studied. In addition, most of the works, both in Russia and foreign countries science, highlight the influence of natural factors on the litter production and the processes of its decomposition, while the impact of local sources of industrial air pollution is rarely considered. The study of the variability of the size, fractional and chemical composition and processes of decomposition of tree litter under conditions of industrial air pollution is important for predicting the dynamics of forest ecosystems subjected to the combined action of natural and anthropogenic factors and reducing the negative impact of production processes on forests.

Today, considerable attention is paid to the intensification of grain production, which depends on the accelerated introduction of highly productive varietal resources with the preservation of the properties of the variety in the process of further reproduction, the production of high-quality and competitive products for the sub-markets of pre-basic, basic, and certified seeds. Improved technologies for growing soft winter wheat should be based on the effective use of the soil and climatic conditions of the studied region, the biological, the genetic potential of varieties, technological innovations in agrotechnical methods of growing crops and the optimal use of material and technical resources. They should be effective for both the producer and the consumer of seed products. The purpose of the research was to determine the features of the formation of seed productivity and sowing qualities of soft winter wheat seeds, depending on the levels of mineral nutrition of plants in the Western Forest Steppe of Ukraine. The methodological basis consisted of general scientific and special research methods. Studies have established that with the low natural fertility of grey forest surface-gley soils of the Western Forest Steppe and considering climate change towards warming with a decrease in precipitation, the introduction of new more productive varieties of intensive type, complex forms of mineral fertilisers, microfertilisers, growth regulators into agricultural production, the questions of the nutrition system of soft winter wheat plants are insufficiently substantiated in this region. The research results presented in the article from 2019 to 2021 demonstrate the issues of the influence of the norm of application of mineral fertilisers with stage-by-stage feeding with nitrogen in different phases of organogenesis on the formation of indicators of seed productivity of varieties of the forest steppe ecological type of soft winter wheat. It was found that the rate of yield of conditioned seeds was the lowest in the control without fertilisers and grew by 16-20% for the application of mineral fertilisers. The seed yield varied from 1.58 t/ha in the control to 4.59 t/ha at the rate of N220P90K160S28, and the multiplication factor, respectively, from 6.3 to 19.8 units. According to this option, the total yield of the large and medium fractions was from 94.9 to 95.2%. A balanced complex of macroelements positively influenced the formation of indicators of sowing qualities of seeds, increasing the weight of 1000 seeds by 5.3-7.5 g, germination energy – from 4.8 to 8.4%, laboratory germination – from 13.6 to 14.4%

Copyright of Plant & Soil Science is the property of National University of Life & Environmental Sciences of Ukraine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The accumulation and distribution of heavy metals (Cu, Zn, Mn, Cr, Ni, Co, Pb, and Cd) in soils of the largest cities in the Amur region, such as Blagoveshchensk, Belogorsk, and Svobodny, are studied. It is found that Zn, Pb, Mn, and Cu are the main technogenic pollutants of urban soils in these cities. The estimation of the fractional distribution of heavy metals (HMs) has shown that the metals found in urban soils accumulate mainly in the following fractions: Cu in the fraction associated with organic matter; Mn in the fraction associated with Fe and Mn oxides and hydroxides; Zn and Cd in the specifically adsorbed fraction associated with Fe and Mn oxides and hydroxides; Ni, Co, Pb, and Cr in the fraction associated with Fe and Mn oxides and hydroxides and organic matter. The proportion of HM mobile forms (oxides associated with organic matter and specifically adsorbed) grows with an increase in the technogenic load. Compared to the background area, the potential mobility of heavy metals increases in urban soils. Among the elements studied, Zn, Cd, and Mn with the potential mobility corresponding to a high level of risk pose the greatest danger. The moderate risk of input into food chains is typical of Pb, Ni, and Co. [ABSTRACT FROM AUTHOR]

Due to the rapid growth in the production and consumption of shisha tobacco in the Russian Federation, it has become necessary to improve the technology using optimal ingredient composition in order to create a high-quality and safe tobacco product. The aim of the research is to improve the technology of manufacturing shisha tobacco based on the optimization of its ingredient composition; to study the influence of the fractional composition of raw tobacco on its quality indicators. Fractional composition of raw tobacco in the production of shisha tobacco, as well as for other tobacco products, is important and affects its quality characteristics. Virginia and Burley tobaccos of the American type are the most demanded ones in the manufacture of shisha tobacco [1]. Sometimes oriental-type tobaccos are used in the bag, which are distinguished by high taste and aromatic qualities. Due to the fact that recently there has been an increase in the demand for Doha Arabian tobacco raw material (this tobacco is known as a high-quality product with a high strength and a pleasant, full and harmonious taste), the idea has arisen to manufacture prototypes of shisha mixtures in which Doha tobacco is used [2]. The article presents the research results: to determine the optimal ingredient composition of hookah tobacco; to study the optimal fractional composition of raw tobacco of various types. As a result of the research the chemical composition of raw tobacco of various types has been analyzed, the tasting and organoleptic evaluation of the prototypes carried out and the tobacco raw material most suitable for the production of shisha tobacco determined; the nicotine content in the condensate of prototypes of shisha mixtures with different fractions of raw tobacco determined; the optimal fractional composition for various types of tobacco raw materials, necessary for the production of a quality product determined.

The transformations of oil components from the Zyuzeevskoye field during catalytic aquathermolysis in the presence of a nickel-containing catalyst precursor and hydrogen donors were studied. It was found that the yield of gasoline and diesel fractions increased by more than 36% in the case of catalytic aquathermolysis in the presence of tetralin. The maximum conversion of asphaltenes was achieved with a simultaneous slowing down of coke formation by four times. The calculation of the structural-group parameters of initial asphaltenes and the products of thermal cracking and catalytic aquathermolysis was made, and the hypothetical construction of their molecular structures was proposed. It was established that the phase composition, ratio, and morphology of nickel catalysts after catalytic aquathermolysis (CA) and catalytic aquathermolysis with tetralin (CA+T) depend on the amount of "free" hydrogen and are represented by Ni0.96S and Ni9S8. [ABSTRACT FROM AUTHOR]

Copyright of German International Journal of Modern Science / Deutsche Internationale Zeitschrift für Zeitgenössische Wissenschaft is the property of Artmedia24 and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

One of the main tasks in the search for environmentally friendly crop-growing methods is to increase soil fertility by improving its physical, chemical and biological parameters. The aim of this study was to determine the effect that the long-term annual application of different types of soil fertility agents (exogenous organic matter: 1. manure, 2. straw in combination with nitrogen fertilization and liming and 3. the addition of biostimulants) had on organic matter properties, including humic acid (HAs) properties. The research was carried out on the basis of soil samples from a ten-year pot experiment which was set up as single-factor pot experiment with four replications. PVC pots with perforated bottoms were filled with soil samples taken from the tilled layer of an arable field where winter wheat was grown in monoculture. The pots were exposed directly to the weather and were left without vegetation. The soil samples were assayed for the content of total organic carbon (TOC), total nitrogen and fractional composition of humus. HAs were extracted with the Schnitzer method and analyzed for the elemental composition, spectrometric parameters in the FT-IR and UV-VIS range and hydrophilic and hydrophobic properties. In addition, EPR spectra were produced. The results showed that the content of organic matter compared to soil without additives increased with the use of manure and the use of straw in the CaO variant and in the form of a mulch. The content of dissolved organic carbon (DOC) ranged from 124.6 to 286.1 mg kg−1 and had strong positive correlation with TOC content. The values of the ratio of carbon content in humic acids to carbon content in fulvic acids (CHAs/CFAs) ranged from 0.71 to 0.99. The use of a biostimulator—with or without the addition of straw—increased carbon sequestration in humic acid molecules, as well as their oxidation level and their share of hydrophobic fractions with the longest retention time. Thus, the addition of UGmax intensifies humification processes, leading to the formation of stable humic acid molecules. [ABSTRACT FROM AUTHOR]

The paper provides an overview of Russian and foreign articles devoted to the study of the tree litter production and decomposition in forest ecosystems subjected to natural and anthropogenic factors. The spatial variability (below crown and between crown spaces) and the seasonal features of the tree litter production, its chemical composition and decomposition processes are poorly studied. In addition, most of the works, both in native and foreign countries science, highlight the influence of natural factors on the litter production and the processes of its decomposition, while the impact of point sources of industrial air pollution is rarely considered. The study of the variability of the size, fractional and chemical composition and processes of decomposition of tree litter under conditions of industrial air pollution is important for predicting the dynamics of forest ecosystems subjected to the combined action of natural and anthropogenic factors and reducing the negative impact of production processes on forests.

The article analyzes the factors that determine the necessity of oil refinery construction in the Kaliningrad region of the Russian Federation. The assessment of the existing and prospective raw material base is performed. The data for the development of the feasibility study for an oil refinery construction are formed and analyzed. Taking into account the outdated data on the parameters of hydrocarbon raw materials produced in the region, as well as significant changes in the raw material base due to the tendency to develop offshore, rather than continental, fields the physical and chemical parameters of the oil fields of the Kaliningrad region are investigated for the possibility of their further use in oil refining in order to obtain high-quality gasoline and diesel fuel. The laboratory studies of oil samples on viscosity, density, fractional composition, content of sulfur, chloride salts, mechanical impurities, water, and flash point determination are carried out on the basis of the Russian state standards. The different variants of the refinery layouts are analyzed, considering the available raw material base. Taking into account the initial data obtained, a preliminary pre-design study of the technological scheme and the refinery mass balance is carried out and presented in the article.

The relevance of the study is caused by the need to reduce the additional aerodynamic load on the main fans associated with the occurrence of pressure drop caused by water build-up effect in mine ventilation shafts. This negative effect can lead to significant increase in the air resistance of the mine and to subsequent unstable operation mode of main fan. Avoiding this effect is important not only for energy save mine ventilation, but also for preventing emergency stop of the main fan. Purpose: finding out the causes and mechanism of the water build-up effect with obtaining qualitative and quantitative estimates of the pressure drop value depending on the air velocity, shaft depth and intensity of the groundwater inflows. Objects: ventilation shafts. Methods: analytical modeling of moisture condensation and droplet movement in an ascending air flow in ventilation shaft; comparative analysis of experimental and model data. Results. The authors have analyzed the experimental data on formation and movement of droplet moisture in the ventilation shafts of various mines. It is noted that the water build-up effect is observed in the range of air velocities from 7 to 12 m/s, but in some cases the effect is absent even despite the presence of thick fog and abundant condensation of moisture on the surface of the shaft lining and other equipment. Three possible scenarios of the effect are considered: accumulation of a large number of drops of a certain size hanging in the air; drops of large size fall along the entire depth of the shaft with a source of moisture release in its upper part and multidirectional movement of drops depending on their size with a source of moisture release located at arbitrary depth. It is established that the first two models do not allow us to obtain a quantitative estimate of the water build-up effect value due to the uncertainty of the fractional composition of drops, the critical size of which increases the pressure drop to infinity. This drawback was eliminated in the third model by introducing the droplet size distribution function, which made it possible to obtain quantitative results. It is proved that the release of moisture from the air cannot be the cause of the water build-up effect, and the cause is the ground water flows into the shaft with intensity of an order of magnitude higher than moisture condensation. Based on the results of numerical modeling, it is shown that the maximum pressure drop occurs when surface groundwater enters the shaft.

It is shown that the fractional composition for heavy oils and gas oils of catalytic cracking can be estimated from the parameters of the optical absorption spectra. The characteristics of the normal distribution of the composition according to the true boiling point (TBP) curves were obtained by processing the experimental data using the Newton– Raphson optimization method. Relationships linking the average boiling points and the dispersion of the normal distribution law for the composition are established. The obtained relationships can be used to obtain initial estimates of the fractional composition of the feedstock and the efficiency of the fractionating columns of the refinery. [ABSTRACT FROM AUTHOR]

Hydrostabilization of straight-run naphtha pyrolysis condensate in the presence of a commercial nickel–chromium catalyst at 80–120°С, hydrogen-to-feed ratio of 0.3–0.8 m3/L, and process time of 30– 120 min was studied. The hydrostabilized pyrocondensate yield increases with an increase in the hydrogen content. The degree of hydrogenation has pronounced temperature dependence at a low-hydrogen hydrogen-to-feed ratio, whereas with an increase in this ratio the temperature dependence levels off. A detailed study of the fractional and component composition of the hydrostabilized pyrocondensate revealed significant differences in the catalyst selectivity depending on the reaction conditions. Low process temperature and high hydrogen-to-feed ratio favor intense formation of aromatic hydrocarbons (at 100°С and hydrogen-to-feed ratio of 0.8 m3/L, the yield was 82 wt %), whereas at elevated temperatures and low hydrogen content the formation intensity shifts toward isoparaffins (at 120°С and 0.5 m3/L H2, the yield was 32 wt %). A possible hydrogenation mechanism ensuring the selectivity of the nickel–chromium catalyst in the process was outlined. The parameters of the fractional and hydrocarbon compositions and the octane numbers of the distillates obtained allow them to be suggested as components of motor fuels. [ABSTRACT FROM AUTHOR]

Conversion of mixtures of fuel oil with iron-containing substrates (carbon adsorbent and lignin, both modified with 0.5 wt % Fe) to hydrocarbon products and hydrogen was studied. The use of microwave radiation in the presence of the above-indicated iron-containing substrates capable of its absorption with the generation of breakdown phenomena and plasma is a promising approach to rapid processing of stable organic compounds of petroleum and natural origin into hydrocarbon products used in organic synthesis and for production of fuel components. [ABSTRACT FROM AUTHOR]