Composition Of Mixture Research Articles

On the issue of the manufacture of ceramic structures in orthopedic dentistry

The article presents a review of ceramic materials used in modern orthopedic dentistry. Currently, the main types of orthopedic structures containing dental porcelain are metal-ceramic, metal-free ceramic crowns, as well as prostheses made using pressed ceramic technology, in particular veneers. All types of prostheses produced using dental porcelain have a common manufacturing technology, which consists in the sequential application of ceramic layers with their subsequent firing. Moreover, for each group of teeth, there are additional masses for firing, for example, masses of the cutting edge, masses simulating various effects (for example, blue, yellow and other shades, imitation of tooth growth lines). These masses are created in order to give future crowns the most natural and aesthetic appearance. All structural components (layers) of ceramics used in the manufacture of ceramic prostheses have a similar chemical composition. The raw material is feldspar glass with inclusions of crystalline quartz. Depending on the conditions of the reactions, the composition of mixtures can be varied and compounds with desired properties can be obtained using the phase analysis method, which will expand the range of domestic ceramic materials produced, which are currently quite scarce. This is especially relevant in modern conditions of import substitution.

Swelling kinetics of mixtures of soybean phosphatidylcholine and glycerol dioleate

Lipid-based drug delivery systems offer the potential to enhance bioavailability, reduce dosing frequency, and improve patient adherence. In aqueous environment, initially dry lipid depots take up water and form liquid crystalline phases. Variation of lipid composition, depot size and hydration-induced phase transitions will plausibly affect the diffusion in and out of the depot. Lipid depots of soybean phosphatidylcholine (SPC) and glycerol dioleate (GDO) mixtures were hydrated for varying time durations in a phosphate-buffered saline (PBS) buffer and then analyzed with Karl Fischer titration, magnetic resonance imaging (MRI) and gravimetrically. Mathematical modeling of the swelling process using diffusion equations, was used to estimate the parameters of diffusion. Both composition of lipid mixture and depot size affect swelling kinetics… The diffusion parameters obtained in Karl Fischer titration and MRI (with temporal and spatial resolution respectively) are in good agreement. Remarkably, the MRI results show a gradient of water content within the depot even after the end of diffusion process. Apparently contradicting the first Fick’s law in its classical form, these results find an explanation using the generalized Fick’s law that considers the gradient of chemical potential rather than concentration as the driving force of diffusion.

SYNTHESIS OF SURFACTANTS FROM NATURAL RAW MATERIALS

This article presents a surfactant synthesized from a mixture of palmitic, oleic, and stearic acids obtained by the distillation and fractionation of oils and fats, as well as ethanol. The synthesis was carried out in 4 stages, which involved the initial formation of an acid mixture, followed by esterification, sulfonation, and ultimately saponification. The composition of the fatty acid mixture was analyzed using chromatography, revealing that palmitic acid makes up the largest proportion at 64.3%, followed by oleic acid at 29.1%. The structure and properties of the surfactant were investigated using modern methods and instruments. The average particle size of the surfactant indicates that it can be classified as a highly dispersed system, with particle diameters ranging from 10 nm to 1 μm. It was observed that the particle size of the surfactant increases once the critical concentration of micellization is reached. The stability of the system in the substance is indicated by a ζ-potential that falls outside the range of 30 mV < ζ < -30 mV. The resulting product exhibits good surface-active properties such as detergency, emulsification, wetting, and foaming ability. According to hydrophilic-lipophilic balance calculations, the synthesized surfactant is classified as a detergent. It demonstrates a high ability to remove pigment-oil and protein contamination at a concentration of 4.0 g/dm3, regardless of the fabric type. Additionally, it was found that the synthesized surfactant exhibits significant emulsifying ability towards industrial oils. The analysis of the surface tension of the surfactant showed that its critical concentration for micelle formation is 4.0 g/dm3. The surfactant demonstrates high wetting abilities on both hydrophilic and hydrophobic surfaces. The foaming properties of the surfactant are satisfactory compared to known surfactants from petrochemical raw materials. Moreover, stable foaming is observed, which directly depends on the surfactant concentration. For citation: Lutfullina G.G., Valeeva E.E. Synthesis of surfactants from natural raw materials. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2024. V. 67. N 6. P. 45-54. DOI: 10.6060/ivkkt.20246706.6984.

STUDY OF HYDROGEN-HELIUM PERMEABILITY OF SILICATE MICROSPHERES AND SORBENT BASED ON THEM

The work is devoted to research on the applicability of the membrane-sorption method for the separation of hydrogen-helium mixtures. The sorption dependences of hydrogen and helium absorption were experimentally obtained for synthetic hollow microspheres made of sodium borosilicate glass of the MS-V-1L type, silica microspheres and granular sorbent based on MS-V-1L microspheres. A significant difference in the rates of sorption processes of hydrogen and helium for the sorbents under study was shown. Based on the gas diffusion model, the kinetic characteristics of absorption, permeability and selectivity coefficients, and dynamic characteristics of the processes of sorption of hydrogen and helium of heliumhydrogen mixtures of various compositions by these sorbents were determined. For silica microspheres, the selectivity coefficient with respect to hydrogen and helium at T = 24 C exceeds 130, and for a granular sorbent based on MS-V-1L microspheres it is about 1000 at T =110 C. The high selectivity values of the studied sorbents confirm the possibility and efficiency of using the membrane-sorption method for the separation of hydrogen-helium mixtures.

Frost Resistance of Silicate Bricks

The article presents the results of a research frost resistance of silicate bricks one of the Russian factories produced in different periods. The change in appearance, weight and strength of silicate bricks during alternate freezing-thawing was evaluated. It has been established that silicate bricks, can meet high frost resistance grades F150-200, in terms of appearance, while the reduction in compressive strength does not exceed 9%. Some increase in brick strength at the initial stage of testing was noted, which is probably explained by the processes of carbonization of free calcium hydroxide and high-basic calcium hydrosilicates, accompanied by their recrystallization into low-basic ones, which is confirmed by the results of differential-thermal and X-ray phase analysis. It is concluded that the frost resistance of silicate bricks is decisively influenced by the mineralogical composition of the cementitious bond. High strength and frost resistance of silicate concrete is provided by the simultaneous presence of low-basic calcium hydrosilicates and α-C2S hydrate in the composition of the new formations. The condition for the formation of such composition of neoplasms is excessive content of lime in the composition of the raw material mixture.

Design and simulation of an efficient gas-liquid separation device for component regulation of zeotropic mixtures

ABSTRACT Improving the overall energy efficiency of thermodynamic cycles relies heavily on the replacement of traditional pure fluids with zeotropic mixtures. The selection of the optimal components within the zeotropic mixture depends on the specific operating conditions of the thermodynamic cycle. Therefore, significant enhancements in performance can be achieved across varying operating conditions by effectively controlling the composition of zeotropic mixtures in the cycle. According to the gas-liquid equilibrium characteristics of the zeotropic mixtures, the adjustment of the medium components and the boundary conditions can be realized if the components can be adjusted through the gas-liquid separation. In this study, a novel device is proposed for automatically regulating the speed of gas-liquid separation in order to separate the components of the zeotropic mixtures. The CFD simulation was utilized to analyze the structural parameters and boundary conditions that impact the efficiency of gas-liquid separation. The results indicate that the adjustable mass flow range of the optimal structure is broadened by 5.5 times compared to conventional gas-liquid separation devices, ranging from 0 kg/s to 0.15 kg/s. Additionally, within this range, the gas-liquid separation efficiency exceeds 95%, representing a 10% improvement over traditional phase separators.

Analysis of the geotechnological potential of heavy oil/bitumen production based on the improved method of well hydraulic production

The work provides an analysis of technologies for the intensification of heavy oil and bitumen production. A variant of its improvement based on the technology of borehole hydraulic production supplemented by the processes of dissolution with hydrocarbon solvents and catalytic aquathermolysis is proposed. The technology involves transfer of main operations of technological chain “extraction-preparation” to the productive layer (transfer of rock to composition of hydraulic mixture; viscosity reduction as a result of heating, dissolution with hydrocarbon solvents, destruction as a result of catalytic aquathermolysis; flotation of oil/bitumen droplets and gravitational separation of the rock). At the same time, in order to increase the efficiency of the technology and use of catalyst, it is proposed to implement the catalytic destruction of asphaltenes starting from mining and continuing after extraction to the surface in a technological installation. Moreover, the required volume of the solvent fraction (taking into account its irreversible losses) is expected to be obtained directly at the deposit as a result of catalytic aquathermolysis and distillation at the final stage of preparation. The improvement will allow to ensure the maximum coefficient of extraction of hydrocarbons with simultaneous modernization to the level suitable for transportation by pipelines without additional preparation.

Effect of SHS powder processing on structure formation and optical transmittance of MgO–Y2O3 composite ceramic

Extending the transparency range of MgO–Y2O3 composite ceramic to wavelength less than 3 μm is highly desirable, as it broadens their potential applications in infrared (IR) optics. This study illustrates the effectiveness of deagglomerating a mixture of magnesium oxide and yttrium sesquioxide powders, derived from self-propagating high-temperature synthesis (SHS), in achieving this goal. The impact of powder deagglomeration on the microstructure and porosity defects of hot-pressed MgO–Y2O3 ceramic was analyzed using electron and IR microscopy. The results showed that the deagglomeration enhanced the homogeneity of the composite grain mixture, slowed down the grain growth, suppressed the formation of large grains, and significantly reduced the number of porosity microdefects in the material. The optical transmittance increased from 42 % to 77 % at a wavelength of 2 μm (for samples with a thickness of 1.2 mm) when deagglomerated powders were used, compared to non-deagglomerated ones.

Modelling and optimization of cryogenic mixed-refrigerant cycles for the cooling of superconducting power cables

For the green energy transition, the transport of large amounts of electrical energy is needed both in densely populated areas and over long distances. Superconducting power cables represent one possible solution, requiring energy-efficient liquid nitrogen re-cooling stations for an economical operation at cable lengths longer than about 1 km to 2 km.In this contribution, a model for simulating cryogenic mixed-refrigerant cycles (CMRC) based on the Joule-Thomson effect and an associated optimization algorithm are presented. The distinctive feature of CMRC is the combination of good scalability of the cooling capacity, adaptability of the mixture to the specific application and an inexpensive process design. While the process is relatively simple, the identification of ideal operating conditions and mixture compositions requires complex modelling. In order to optimize these characteristics for CMRC processes, the Differential Evolution algorithm is adapted to a model built in Mathematica. Thermodynamic property data is calculated with the Peng-Robinson Equation of State as part of CoolProp, an open-source thermophysical property library. First simulation results are presented and further improvements are being discussed.

Experimental investigation on CO2-based zeotropic mixture composition-adjustable system

CO2 is a promising natural working fluid for its environment-friendly, property-stable and low-cost, and CO2-based zeotropic mixture could enhance the comprehensive performance of combined cooling and power cycle (CCP). Generally, CCP operates in a wide temperature range, and the fixed operating composition could not realize the optimal match for two sub-cycles. Zeotropic mixture composition adjustment could realize targeted thermal match of sub-cycles and further enhance the performance of CCP. However, systematic research on composition-adjustable CCP is limited in theoretical simulation, and there is still a lack of experimental evidence for the performance enhancement of composition adjustment on CCP. Besides, the feasibility of composition adjustment on CCP has not been fully verified through experimental method yet. In this study, an experimental prototype of CO2-based composition-adjustable CCP is established, the approach to realize composition adjustment is investigated, and the systematic test is carried out. Experimental results show that the introduction of composition adjustment is beneficial to the performance of CCP. Under the same boundary conditions and similar refrigeration conditions, composition-adjustable CCP could export 13.72 % more net power than composition-fixed CCP when the initial charged CO2 mass fraction equals 0.246, and the improvement is more apparent when the initial charged composition gets larger.

Combined ns pulsed-RF excitation and impedance matching considerations for the production of moderate E/n atmospheric pressure discharges for gas conversion

Sub-breakdown radiofrequency (RF) discharges enabled by a nanosecond (ns) pulse ignition source are studied at atmospheric pressure in a range of gas mixtures from completely inert (in Ar) to completely reactive (in CO2). An electrical characterisation of the continuous wave (CW) RF discharge (13.56 MHz) is performed to determine plasma impedance and plasma power dissipation. Two different measurement methods to electrically characterize the system are described and compared. One method uses in-situ measurements of discharge parameters (voltage, current and the phase angle), and the other method performs ex-situ measurements of the load circuit using a vector network analyser. It was found that RF plasma power deposition depended on the applied RF power as well as the gas mixture composition. Using the in-situ voltage, current and phase angle measurements, plasma power deposition was calculated to be as much as 85% and 76% of the applied RF power for the pure Ar and pure CO2 cases, respectively. A preliminary qualitative assessment of the plasma composition was performed by optical emission spectroscopy, and CO2 conversion by mass spectrometry. CO2 to CO conversions of 11.2% and 5.5% in a 20:80 (CO2:Ar) mixture and in 100% CO2, respectively, were observed. This study demonstrates a RF plasma source for gas conversion applications at atmospheric pressure in a completely reactive gas.

Working process model development of the gas turbine engine combustor fueling on methanol

The use of methanol as a fuel for aircraft and stationary gas turbine engines (GTE) is a priority direction in engine building. It is well known that when modeling the GTE performances using first-level mathematical models, there is an error in calculating specific fuel consumption, which is caused by the simplified description of the GTE combustor working process. The object of the study is the working process in the GTE combustor fueling on methanol. The peculiarity of the developed mathematical model of the working process of the GTE combustor is the use of enthalpy dependencies on temperature, pressure, and mixture composition. Enthalpy dependencies in this form implicitly account for the effect of thermal dissociation and allow for the correct formulation of the equivalent combustion reaction path. For two components (H2O and CO2), accounting for pressure leads to the fact that at standard temperature and partial pressures exceeding the saturation pressure, these components exist in a liquid state. This situation, with a constant enthalpy increment in the equivalent process of heating the combustion products from the standard temperature to the temperature at the end of adiabatic heat supply, decreases this temperature. Clarification of the temperature at the combustor outlet leads to changes in all calculated combustor performances, including the combustor fuel air ratio. The calculation results of the fuel air ratio are compared with known experimental data of the General Electric CF6-80A engine combustor (USA). The average calculation error of the fuel air ratio does not exceed 4 %. The developed model can be implemented in existing and developing mathematical models of gas turbine engines for temperatures at the end of the combustion process below 2,600 K

Effect of Mixture Composition on the Photophysics of Indoline Dyes in Imidazolium Ionic Liquid-Molecular Solvent Mixtures: A Femtosecond Transient Absorption Study.

We conducted a study on the photophysics of three indoline dyes, D102, D149, and D205, in binary mixtures of ionic liquids (IL) and polar aprotic molecular solvents (MS). Specifically, we examined the behavior of these dyes in IL-MS mixtures containing four different imidazolium-based ILs and three different polar aprotic MSs. Our investigation involved several techniques, including stationary absorption and emission measurements, as well as femtosecond transient absorption (TA) spectroscopy. Through our analysis, we discovered a peculiar behavior of several photophysical properties at low IL mole fractions (0 < XIL < 0.2). Indeed, in this range of mixture composition, the absorption maximum wavelength decreases noticeably, while the emission maximum wavelength and the Stokes shift, expressed in wavenumbers, reach a maximum. while a minimum occurs in the relative quantum yield and the excited state lifetime. These results indicate that the solvation of dye undergoes a large change in this range of mixture composition. We found that, at high ionic liquid content, the excited relaxation times are correlated with the high viscosity, while at low content, it is the polarity of the solvent that influences the behavior of the excited relaxation times. At a mixture composition of around 0.10, the behavior of the photophysical properties of the studied IL-MS mixtures indicates a crossover between situations where the solvation is dominated by that of ions and that dominated by the solvent.

Comparison of Predictive Modeling Concrete Compressive Strength with Machine Learning Approaches

Accurately predicting concrete compressive strength is fundamental for optimizing mix designs, ensuring structural integrity, and advancing sustainable construction practices. Increased demands for safer, more durable infrastructure necessitate effective predictive concrete compressive strength models. This research aims to compare the effectiveness of six machine learning models such as Linear Regression, Random Forest, Support Vector Regression (SVR), K-Nearest Neighbors (KNN), Gradient Boosting, and XGBoost to predict concrete compressive strength. Used a dataset of 1030 instances with varying mixture compositions, conducted extensive exploratory data analysis, and applied feature engineering and data scaling to enhance model performance. Assessments were performed with a 5-fold cross-validation approach with the R-squared (R²) metric. In addition, the SHAP value is used to understand the influence of each feature on the compressive strength results. The results revealed that XGBoost significantly outperformed other models, achieving an average R² value of 0.9178 with a standard deviation of 0.0296. Notably, Random Forest and Gradient Boosting also demonstrated robust capabilities. Based on our experiment, these models effectively predicted compressive strengths close to actual measured values, confirming their practical applicability in civil engineering. SHAP values provided insights into the significant impact of age and cement quantity on model outputs. These results highlight the advanced ensemble methods' effectiveness in concrete compressive strength prediction and underscore the importance of feature engineering in enhancing model accuracy.

Physical, Nutritional, Textural and Sensory Properties of Wheat Bread Supplemented with Soybean: Finger Millet and Flax Seeds flour

Two-third population of the world is under-nourished, and lack in required quantity of minerals and proteins. United Nations launched 17 Sustainable Development Goals (SDGs) of which SDG-3 is “health and well-being” to improve the position of malnutrition worldwide. Proteins are essential to human health and in post-covid-19 era, plant proteins production industry is booming to meet the demand of enhanced requirement of vegetative proteins by consumers. Proteins Digestibility-Corrected Amino Acid Score (PDCAAS) of soy protein is 1.00 which is closer to some of the proteins from animal sources. Soy proteins contain balanced amounts of essential amino acids except sulfuric-amino acids like methionine. The blended flour contained equal quantities of soybeans, finger millet, and flax seeds and was added at varying proportions (10%, 15%, 20%, and 25%) with refined wheat flour for fortification purpose. The comprehensive evaluation encompassed nutritional, sensory, and physical attributes of the resulting multigrain bread when compared with a control loaf made exclusively from wheat flour. The bread fortified with a 10% composite flour mixture exhibited properties equivalent to the control bread across parameters such as expansion, specific volume, color, and crumb hardness but with enhanced nutritional value. The data revealed that supplementation of bread with 10% composite flour blend led to a discernible increase in levels of dietary fiber and proteins. We may safely conclude that the incorporation of a well-balanced composite flour blend, comprising soybeans, finger millet, and flax seeds, at 10% level offers a promising avenue to fortify wheat flour bread with enhanced nutritional content that may be helpful in improving the nutritional status of people as a part of Sustainable Development Goals of UN as the bread is a common food item of the poor also. Objective: Bread is the common food of all people throughout the world and wheat flour the most abundant component that contain high quantity of gluten and is deficient in balanced nutrients. The purpose of this study was to develop highly nutritious multi-grain bread to fight with malnutrition as a part of Sustainable Development Goal-3 of UN. Methodology: Composite flour containing equal amounts of soybean, finger millet and flax seed was prepared. The bread was prepared using different combinations of wheat flour with 10, 15, 20 and 25% composite flour. Physio-chemical and sensory properties of wheat flour (control) and different combinations with composite flour were measured using standard parameters and protocol. Results: The nutritional, sensory, and physical attributes of the multigrain bread when compared with a control wheat flour loaf, revealed that the bread fortified with a 10% composite flour mixture possessed similar expansion, specific volume, color, and crumb hardness with that of control wheat flour bread but showed enhanced nutritional value. The data further revealed that the supplementation of bread with 10% composite flour blend led to a discernible increase in levels of dietary fiber and proteins. These augmented nutritional components may contribute to the overall health benefits of multigrain bread.

Assessment of CH4 Emissions in a Compressed Natural Gas-Adapted Engine in the Context of Changes in the Equivalence Ratio

The results of diagnostic tests under steady-state speed conditions of an unloaded engine do not fully reflect the emissivity of vehicles adapted to run on natural gas. Therefore, it is reasonable to pay attention to the emissions performance of these vehicles under dynamic conditions. In this regard, the tests were carried out on a chassis dynamometer with the engine fueled by gasoline and natural gas. Due to the area of operation of natural gas vehicles being usually limited to urban areas, the urban phases of the NEDC (New European Driving Cycle) and WLTC (Worldwide harmonized Light-duty vehicles Test Cycle) were adapted. While CO2 emissions are lower when fueled by natural gas, CH4 emissions can be high, which is related to momentary changes in the composition of the combustible mixture. Although CH4 emissions are higher when the engine runs on natural gas, the CO2eq value is, depending on the driving cycle, about 15–25% lower than when running on petrol. Additionally, studies have shown that in engines adapted to run on CNG (compressed natural gas), it is advisable to consider the use of catalytic converters optimized to run on natural gas, as is the case with vehicles which are factory–adapted to run on CNG.

Theoretical analysis and numerical validation of the mechanisms controlling composition noise

A new definition of entropy fluctuation is provided in this paper, that allows properly separating entropy and mixture composition fluctuations. This decomposition into linearly independent variables prevents from overestimating compositional noise in indirect noise prediction. When considering quasi one-dimensional flow in nozzles, a new resulting system of linearized Euler equations is obtained. Two analytical solutions of this system of equations are investigated in this study, one dedicated to low-frequency perturbations and another one for all frequency perturbations. This new theory is then validated by comparing the model predictions with direct numerical simulation of nozzle flows in which composition fluctuations are pulsed. To do so, new Navier–Stokes characteristics boundary conditions to account for the new properly defined entropy wave are provided. Furthermore, non-reflecting inlet boundary conditions have been newly derived, relaxing on the axial mass-flow rate, static temperature and species mass fractions. Finally, a parametric study based on an air-kerosene (equivalent C10H20) mixture and an ideal framework shows that composition noise can reach a maximum of 10% of entropy noise for lean combustion and choked nozzle while for rich combustion, composition noise and entropy noise show comparable levels.

Processing-microstructure relationships in ferrous alloys via mixed powder laser powder bed fusion

Three different approaches to control the phase formation in powder bed fusion - laser beam (PBF-LB) printing using a powder mixture of duplex stainless steel (DSS) 2507 and austenitic stainless steel 316 L were examined: (i) in situ solid state reheating, (ii) utilization of an island scan strategy, and (iii) switching process parameters between layers of a build. Analytical modeling was used to determine the time-temperature profiles during each of these processes, and was combined with thermodynamic simulations through Thermo-Calc to predict and explain the phase formation measured experimentally. It was found that the reheating from additional layers was critical to the nucleation of austenite, even with the increased Ni content in powder mixtures. This was evident in the island scan strategy prints where the corners of the islands showed significantly less austenite (∼45%) as compared to the centers of the islands (∼96%), as well as in the multi-layer samples where alternating laser power for fixed chemical composition of powder mixture resulted in varying content from ∼75% (lower power) to ∼90% (higher power). Additionally, in situ reheating using a lower power laser was capable of minimally increasing the austenite content layer-by-layer, by raising the temperature of the layer above the nucleation temperature of austenite. These results showcase the capability of PBF-LB to manipulate phase structure in ways not possible through traditional manufacturing techniques, as well as the ability of Thermo-Calc to accurately predict the trends observed that can be applied to other alloy systems.

Exploring the geotechnical and microstructural properties of composite mixtures for landfill liner materials: an experimental investigation.

The present study directs the need for the development of an economical composite mix comprised locally available soil and industrial waste which satisfy the design parameters of the municipal solid waste (MSW) landfill. The local soil, bentonite, and fly ash mixtures are mixed in different proportions to evaluate the geotechnical and microstructural characteristics for suggesting an optimum composite mix that fulfills the design parameters of landfill liners. The curing periods of different mixes are also considered while evaluating the unconfined compressive strength (UCS) characteristics. The microstructure of the mixtures is examined using advanced imaging techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDAX) to gain insights into the changes at the microscale level due to the inclusion of fly ash. It is observed that soil-bentonite-fly ash composite mix in a ratio of 65:15:20 aligns with the optimal design characteristics required for a landfill liner. Notably, for this composite mix, both liquid limit (LL) and plastic limit (PL) show a significant increase of 48.57% and 32.33% respectively, while the optimum moisture content (OMC) rises by 11.25%. Conversely, maximum dry density (MDD) experiences an 8.79% decrease. Moreover, the free swell index (FSI) escalates by 113%, whereas hydraulic conductivity (HC) records a substantial reduction of 96.04%. Moreover, the UCS exhibited a notable increase of 209% after a 28-day curing period. The highest strength is achieved initially by soil mixed with 20% fly ash, followed by a blend containing 15% bentonite. Therefore, proper fly ash content in filler and other binder materials is an effective and sustainable approach that not only solves the disposal issue but also enhances the material's engineering characteristics, justifying its suitability to be used as a landfill liner.

Productivity of the ewe's lambs Romanov breed when using a complex of mineral and vitamin supplements in diets

Relevance. It is known that the mineral composition of the feeds of the Republic of Bashkortostan used in animal diets, in terms of calcium, phosphorus, magnesium, copper, cobalt and sulfur, does not meet the needs of animals. The deficiency of minerals is especially high in growing young animals.In this regard, the development and scientific justification of the use of a complex mineral and vitamin feed additive (hereinafter CMVFA) in the diets of growing young sheep, which stimulate digestion and digestibility of nutrients in the diet, thereby increasing productivity, is of particular importance.Methods. To study the effectiveness of feeding KMVKD in the diets of the Romanov breed yarok on the indicators of body weight gain in peasant farming conditions, 4 groups of yarok were formed on the principle of pairs of analogues (10 heads each). Yarki of the control group received in addition to the main diet at the rate of 20 g of monocalcium phosphate and 15 g of premix per head (P81-1-89). The yarks of the experimental groups of KMVKD were introduced into the composition of crushed grain mixtures: made according to recipes No. 1 — for the first, No. 2 — for the second, No. 3 — for the third (35 g per head per day).Results. With a small difference in the intake of substances between the groups, the use of UMVD of 35 g per head per day had a significant impact on body weight gain. During the experiment period, the average daily weight gain in animals of the control group was 165 g, and in the experimental groups, respectively, 174.75 g, 183.52 g and 190.68 g, or more by 5.91%, 11.22% and 15.56% compared with the control. The level of profitability of production in the experimental groups increased by 10.60%, 16.03% and 20.54% compared with peers from the control group.