Sulfate Type Research Articles

Effect of sulfate on the compatibility between polycarboxylate superplasticizer and cement-based materials with or without silica fume

Polycarboxylate superplasticizer (PCE) is a crucial raw material used for preparing concrete. However, there has always been a compatibility issue between PCE and different types of cementitious materials due to their varying qualities. In concrete raw materials, the types and contents of sulfates have a significant impact on compatibility, and it is well-established that a competitive adsorption exists between PCE and sulfate ions solubilized in the interstitial solution of cement paste, which may cause a loss of the dispersing properties. However, previous studies focused on the effect of sulfate on the compatibility between PCE and cement, and there was a lack of research on silica fume. In this study, the workability of fresh cement and cement-silica fume paste and the mechanical properties of harden mortar were evaluated in the presence of different concentrations of five types of sulfates (Na2SO4, K2SO4, MgSO4, KAl(SO4)2, and CaSO4·2H2O) added in aqueous solution. The results show that soluble sulfates have a more adverse effect on the compatibility between PCE and cement-based materials with or without silica fume than slightly sulfate. And the effects of different sulfates on saturation points of PCE in cementitious materials and the mechanical properties of cement and cement-silica fume mortar are various. Finally, it is important to note that a high sulfate content in the solution can lead to salt precipitation of PCE, which is highly undesirable.

Source identification and potential health risks of fluoride and nitrate in groundwater of a typical alluvial plain

A comprehensive understanding of the role of natural and anthropogenic factors in groundwater pollution is essential for sustainable groundwater resource management, especially in alluvial plains with intensive anthropogenic activities. Numerous studies have focused on the contribution of individual factors on groundwater pollution in alluvial aquifers, but distinguishing the effects of natural and anthropogenic factors is limited. In this study, 64 wells were sampled in different seasons from the Yellow River alluvial plain in China for hydrochemical and isotopic analysis to investigate the spatiotemporal distribution, sources and health risks of fluoride and nitrate in alluvial aquifers. Results showed that fluoride contamination was widely distributed without significant seasonal variation, and 78.1 % of the dry season samples and 65.6 % of the wet season samples showed fluoride concentrations above the permissible limit (1.5 mg/L). High-F− groundwater was generally accompanied by Na-HCO3 and Na-HCO3·SO4 water types. Fluoride was from a natural origin mainly associated with mineral dissolution, competitive adsorption, cation exchange, and evaporation. Groundwater nitrate contamination was spatially sporadic and showed significant seasonal differences. Only 13.6 % of the dry season samples and 3.2 % of the wet season samples had NO3− concentrations exceeded the permissible limit of 50 mg/L. The hydrochemical phase evolved from bicarbonate or sulfate type to chloride type with increasing nitrate concentration. Manure and sewage attributed to agricultural activities contributed the most nitrogen to groundwater, followed by soil organic nitrogen and chemical fertilizers, revealing the anthropogenic origin of nitrate. Nitrification was the dominant nitrogen transformation process in the wet season, and denitrification was prevalent in the dry season. Oral ingestion of high fluoride groundwater was a major threat to human health, especially for infants. This study provided a significant reference for water resources management in alluvial aquifers.

Structure-based modeling of critical micelle concentration (CMC) of anionic surfactants in brine using intelligent methods

Critical micelle concentration (CMC) is one of the main physico-chemical properties of surface-active agents, also known as surfactants, with diverse theoretical and industrial applications. It is influenced by basic parameters such as temperature, pH, salinity, and the chemical structure of surfactants. Most studies have only estimated CMC at fixed conditions based on the surfactant’s chemical parameters. In the present study, we aimed to develop a set of novel and applicable models for estimating CMC of well-known anionic surfactants by considering both the molecular properties of surfactants and basic affecting factors such as salinity, pH, and temperature as modeling parameters. We employed the quantitative-structural property relationship technique to employ the molecular parameters of surfactant ions. We collected 488 CMC values from literature for 111 sodium-based anionic surfactants, including sulfate types, sulfonate, benzene sulfonate, sulfosuccinate, and polyoxyethylene sulfate. We computed 1410 optimized molecular descriptors for each surfactant using Dragon software to be utilized in the modelling processes. The enhanced replacement method was used for selecting the most effective descriptors for the CMC. A multivariate linear model and two non-linear models are the outputs of the present study. The non-linear models were produced using two robust machine learning approaches, stochastic gradient boosting (SGB) trees and genetic programming (GP). Statistical assessment showed highly applicable and acceptable accuracy of the newly developed models (RSGB2 = 0.999395 and RGP2 = 0.954946). The ultimate results showed the superiority and greater ability of the SGB method for making confident predictions.

Study on the Effect of Three Types of Calcium Sulfate on the Early Hydration and Workability of Self-Compacting Repair Mortar.

Despite having a high early mechanical strength and using sulfoaluminate cement as the primary cementitious material, self-compacting repair mortar (SCRM) suffers from rapid hydration rates leading to construction time constraints. This study examined how several forms of calcium sulfate, including hemihydrate gypsum, anhydrite, and dihydrate gypsum, affected SCRM's workability, hydration process, and microstructure. The outcomes demonstrated that adding hemihydrate gypsum sped up SCRM's early hydration rate and boosted its expansion rate. For a cement with 8% hemihydrate gypsum, 6 h after adding the water, the flexural strength and compressive strength increased by 39.02% and 34.08%, respectively. The hydration rate of SCRM can be efficiently delayed by dihydrate gypsum, although the result is subpar. The material exhibited the lowest fluidity loss in 20 min, the setting time was extended, and the 28-day flexural and compressive strengths were raised by 26.56% and 28.08%, respectively, after adding 8 percent anhydrite.

Geochemistry of Salt Lakes of East Kazakhstan

The main purpose of this study is to determine the chemical composition of salt lakes in the borovoye, Delbegetei and Chagan-Shar sites (East Kazakhstan). For the study, samples were selected for analytical studies, as well as field surveys were conducted on the geometrization and linking of lakes within the borovoye, Delbegetey and Chagan-Shar sites and sampling of Water, bottom sediments, rapes. 44 water samples, 66 rapes and bottom sediments were taken. The main cation is sodium, which contains from 50.28 to 2539.04 mg/l, with an average value of 798.9 mg/L (60 mg-EQ %). The relative composition of the second is 25 mg-EQ % of calcium, and magnesium is 15 mg-eq % [1]. Only the sulphate type of lakes differs in the ash-Shar section. According to the chemical composition of lakes of the sulphate type, all 11 lakes are characterized by relatively low mineralization, with an average pH range of 7.4 to 8.8 and belong to freshwater. High values of hydrocarbonates are observed in Lake 7SH at 2976 mg/L, on average, the proportion of sulfate ions is 46 mg-EQ%. It was found that the increase in salinity in the waters of the studied lakes of East Kazakhstan is not due to the accumulation of sulfates and chlorides in the water, and the composition increases in proportion to the salinity.

Metastable Phase Formation in Electrodeposited Co-Rich Co-Cu and Co-Ni Alloys

In a previous work [El-Tahawy et al., J. Magn. Magn. Mater. 560, 169660 (2022)], we reported that from a sulfate type bath, hcp-Co can be electrodeposited at high pH and low current density and investigated the structure and magnetoresistance (MR) characteristics of such hcp-Co electrodeposits. Based on this earlier work, Co-rich Co-Cu and Co-Ni alloy electrodeposits were prepared under the same conditions by adding varying amounts of CuSO4 and NiSO4, respectively, to the CoSO4 bath. According to the results of detailed structural studies by various X-ray diffraction (XRD) geometries, in both the Co-Cu and Co-Ni systems an hcp phase formed exclusively up to about 2 at% of the alloying element. Above this concentration, a significant fcc phase fraction appeared in Co-Cu and a minor fcc fraction in Co-Ni up to about 8 at%. This means that the destabilization effect of Cu on hcp-Co is higher than that of Ni. Although the reduction of the stability of hcp-Co with increasing Cu and Ni content is a well-known phenomenon, a quantitative comparison of this effect in Co-Cu and Co-Ni alloys is missing from the literature. The measured lattice constants are analyzed in comparison with Vegard’s law for the Co-Cu and Co-Ni element pairs deduced from data previously reported for the hcp and fcc phases of all three pure elements. For Co-rich Co-Ni alloys, the concentration dependence of the lattice parameters was found to follow Vegard’s law for both the hcp and fcc phases due to the miscibility of the two components. For the Co-rich Co-Cu alloys, the data indicate a positive deviation from Vegard’s law for both the hcp and fcc phases in agreement with the known similar behavior of fcc Co-Cu alloys for the whole composition range. The positive deviation from Vegard’s law in the Co-Cu system is due to the excess mixing volume required for solid solution alloy formation of these immiscible elements in either phases. The MR data are discussed in the light of the observed phases and of the MR parameters reported in our previous work on the hcp and fcc phases of pure Co.

Chemical admixtures for concrete: Effects of accelerators on the volume stability of cement-based materials

In this study, the addition of sodium aluminate type alkali liquid accelerator (AR), aluminum sulfate type alkali-free liquid accelerator (AS), and fluoroaluminate type alkali-free liquid accelerator (AF) were used to test the volume stability, mass loss, and internal humidity change of cement mortar. The impact of various accelerators on the volume stability of cement mortar was examined through a comprehensive analysis utilizing MIP, XRD, IR, SEM, and other characterization techniques. The results show that the shrinkage deformation of the cement mortar mixed with AR type alkali accelerator was more serious than that of the mortar mixed with the other two alkali-free accelerators, and the shrinkage deformation of the cement mortar was more significant with the increase of the dosage of the three accelerators. The most significant reason for the shrinkage and deformation of the AR type alkali accelerator is that the conversion of AFt to AFm reduces the volume of swellable substances and the pore size distribution of 10–50 nm produces more significant capillary negative pressure. The reason for the smaller shrinkage deformation of the mortar mixed with two alkali-free accelerators is that its main component contains a certain amount of SO42-, and the undersulfated reaction will occur relatively less frequently. Furthermore, the 10–50 nm pore size distribution is less than mortar with AR type alkali accelerator, and the capillary negative pressure is lower. Additionally, quantitative analysis of the components was conducted to confirm the factors responsible for the varying levels of shrinkage deformation in the cement mortars with three accelerators.This paper offers valuable guidance for effectively employing accelerators in shotcrete applications.

Biogeochemical State of Salinized Irrigated Soils of Central Fergana (Uzbekistan, Central Asia)

The Central Fergana region is one of the overpopulated regions of Central Asia, which includes parts of Uzbekistan, Kyrgyzstan, and Tajikistan. Here, in the dry subtropical climate are the most ancient, irrigated oases used for agriculture. Fergana valley is the key to the food security of the region as a whole. The article provides information on diversity and chemical composition of newly developed, new and old-irrigated Calcisols soils formed on alluvial and alluvial–prolluvial sediments. Soils are poor with organic matter (0.37–0.81% of organic carbon), with high nitrogen content (C/N ratio is 4.92–5.79), and with neutral (7.01–7.30) pH values. Data on the content and the ratio of the key components of soil salinity (Na2CO3, Ca(HCO3)2, CaSO4, MgSO4, Na2SO4, NaCl) and the bulk content of salts in soils under different irrigation regimes are presented. It was shown that Na2CO3 concentration is minimal in all the soils, and this salt presents only in ground waters (0.100–0.135 g L−1). Newly irrigated soils are characterized by higher content of salts than old irrigated soils. All the soils investigated are characterized by increasing salinity rate within the soil depth with the highest content of all salts in ground waters. This chloride–sulfate type of salinization is most pronounced in all the soils studied. Gypsum content in agricultural soils results in limited water and nutrient retention and the potential for dissolution, primarily in response to irrigation. The soils of the Fergana Valley are also subjected to polychemical pollution, so the content of trace elements in them was studied. Irrigated meadow-takyr and meadow-saz soils show low levels of environmental hazard, but irrigation results in accumulation of such trace elements as nickel (30 mg kg−1), arsenic (11.75 mg kg−1), bromine (5.00 mg kg−1), antimony (1.48 mg kg−1), cesium (5.00 mg kg−1), and hafnium (2.97 mg kg−1). Irrigation also affects the soil texture and thus increases fine particle percentages in the superficial soil horizons. Thus, the complex chemical characteristics of salinized soils are presented for numerous irrigated landscapes of the region.

Resistance to Sulfate Attack Under Drying–wetting Cycles of Reactive Magnesia–microbial Cured Electrolytic Manganese Residue

The reactive MgO (r-MgO)-microbial curing technology can not only effectively improve the strength of electrolytic manganese residue (EMR) but also repair heavy metal ions. By conducting unconfined compressive strength (UCS) test, heavy metal leaching test, X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), and mercury intrusion porosimetry (MIP), the effects of the type and concentration of sulfate on the strength and repair of heavy metals of the cured EMR under drying–wetting (DW) cycles were studied, and the strength and the evolution mechanism of heavy metal remediation is elucidated. The results indicate the following: With the increase in the number of DW cycles, the dry density of the samples in high concentration of MgSO4 first increased slightly and then decreased gradually and became stable. The dry density of the samples in Na2SO4, low concentration of MgSO4, and water generally showed a downward trend. The pH of the soaking solution slightly decreased, and the leaching concentration of heavy metal Mn2+ ions always remained at a low level. The UCS of the samples in MgSO4 first increased slightly and then decreased gradually, and then became stable. The amount of cured products first increased and then decreased, and the size of internal pores first decreased and then increased. The UCS of the samples in Na2SO4 and water gradually decreased and became stable. The amount of cured products gradually decreased, and the size of internal pores gradually increased. The research results provide a theoretical basis for the evaluation of resistance against the sulfate corrosion of cured EMR under DW cycles.

Interactions Evaluation between the Jouamaa Hakama Groundwater and Ouljat Echatt River in the North of Morocco, Using Hydrochemical Modeling, Multivariate Statistics and GIS

The processed discharges from Tangier Automotive City’s (TAC) Chrafate Wastewater Treatment Plant (WWTP) contaminate the Jouamaa Hakama groundwater and the Ouljat Echatt river. We aimed to study the unknown interactions between surface water (SW) and groundwater (GW). A total of nine Jouamaa Hakama GW samples and eleven Ouljat Echatt SW samples were taken and analyzed in 2021 and 2022 to determine 16 physical and chemical parameters (pH, temperature (T), electrical conductivity (EC), dissolved oxygen (DO), total hardness (TH), turbidity (TURB), and total dissolved solids (TDS), cations: Na+, K+, Mg2+ and Ca2+, anions: Cl−, CO32−, HCO3−, NO3−, and SO42−). For exploitation of the data, we used a methodology based on hydrochemical modeling (HM), principal component analysis (PCA), Water Quality Index (WQI), Irrigation Water Quality Index (IWQI), inverse distance weighted interpolation (IDW) using Geographic Information Systems (GIS), and regression analysis (RA). We studied the interaction of the surface water of the river (contaminated by discharges from the WWTP) with the shallow groundwater on a strip of 100 m on either side of the river to understand the transverse and longitudinal dispersion of this pollution The investigations indicated that the major ions found in GW and SW were characterized in a different order in the anion list order Cl− > CO32− > NO3− > HCO3− > SO42− and Cl− > SO42− > CO32− > NO3− > HCO3−, respectively, while the concentrations of cations showed the same order for both: Na+ > Ca2+ > Mg2+ > K+. As a result, GW showed in the Piper diagram the type of sodium chloride to magnesium carbonate, while SW belongs to the sodium chloride to magnesium sulfate type. The WQI showed that the river waters are all unsuitable for use (WQI > 100), while the GW is of poor quality (WQI > 76). Moreover, the results of the GW–SW interaction along the river revealed a significant relationship (R2 = 0.85), which means that strong circulation and the infiltration of contaminated SW into shallow GW occur in this area. The approaches followed have been proven effective in evaluating water quality for human and animal uses. These results can help decision-makers in the region take suitable management measures to mitigate this environmental problem.

Analisis Karakteristik Tipe Fluida Mata Air Panas Di Hutan Pinus Lahendong Dengan Menggunakan Spektrofotometri

Pine Forest is one of the tourist attractions in Lahendong Village, which has geothermal manifestations in the form of hot springs, which shows that the area has geothermal potential. The purpose of this study was to determine the type of fluid manifested by hot springs in the Pine Forest using geochemical methods. The results of this study indicate that the temperature at the manifestation is 40°C while the degree of acidity of the pH of hot water has a value of 4 which indicates the acidity level of hot water is acidic. The type of fluid that exists in the manifestation area of hot water in the Pine Forest is the type of fluid sulphate water and sulfate water is a fluid that is formed at shallow depths and is formed as a result of the condensation process of geothermal gas towards near the surface. This is because the results of chemical analysis show that the element SO4 is the most dominant element and contains SO4 gas. Hot water that has a sulfate type is water that is formed at shallow depths and is formed as a result of the process of condensing geothermal gas towards near the surface. The geothermal gas with gas content (water and carbon) is basically dissolved in the fluid content which is located in the deep zone but separated from the chloride water. Sulphate water is usually at the boundary and not far from the main upflow zone.

Wpływ zanieczyszczeń na zawartość składników odżywczych w glebie

Soil degradation occurs as a result of the ingress and accumulation of excessive amount of pollutants in the soil. The article presents the results of theoretical and experimental studies of the complex effect of soil contamination (concentration of petroleum products, toxic salts, dense residue, sodium ions, sulfate ions, magnesium ions, calcium, chloride ions, bicarbonate ions) on the content of nutrients (alkaline hydrolyzed nitrogen, phosphorus, potassium, humus). A detailed analysis of scientific papers has been carried out, based on which the main scientific tasks solved in the article have been formulated. It has been established that soil-salt processes are insufficiently studied and are the object of scientific research in recent years. At the first stage of research, sampling was carried out and the content of nutrients and pollutants in the soil was determined. Determination of element concentrations was performed by collecting soil samples and their subsequent laboratory testing. At the second stage, a correlation-regression analysis of the obtained data was performed and multiple linear regressions were established. The interaction of substances in the soil was determined by analyzing the obtained multiple linear regressions. Two types of soils were studied: with chloride and with sulfate type of salinization. For soils with chloride type of salinity, dependences have been established for the content of humus, alkaline nitrogen and potassium, while in case of phosphorus multiple linear regression does not exist. For soils with sulfate type of salinization, multiple linear regression dependences of concentrations of alkaline nitrogen, phosphorus, potassium have been determined. It is established that the complex influence of the studied elements is decisive. No regression dependence was found for the humus content, which indicates that the concentration of the studied elements has almost no effect on the humus content in the soil. Comparison of the obtained multiple linear regressions with the results of laboratory studies showed a good correlation between these data series. The obtained regularities of pollutant and nutrient interactions in soils are expected in future to enable creation of scientific bases for development of new methods of desalination of soils polluted by formation waters as well as for planning effective reclamation actions.

Analysis of the mechanism for H2S generation and the main factors controlling gas production in coal seams

H2S is a poisonous and reactive gas found in coal mines, and it brings serious risks to coal mining. However, research on the mechanism for H2S generation in coal seams is rare, and information on the causes of the concentration anomalies is relatively limited. Simulations of coal thermal evolution and the mechanism for coal thermochemical sulfate reduction (TSR) are also scarce. Herein, the processes for H2S generation from coal under different conditions were simulated by combining high-temperature and high-pressure sealed simulations of TSR under different conditions. Gas formation in the TSR reactions occurring during pyrolysis, different sulfate types, salinities and coal particle sizes were discussed, H2S and other gas products were compared, the assumptions regarding TSR reactants and the product generation from coal were illustrated, and the H2S generation mechanism occurring during coal pyrolysis and the TSR reaction were revealed. H2S, CH4, C2-C5, and nonhydrocarbon gases were detected after the pyrolyses. The TSR reaction was the main source of thermogenic H2S and can be divided into the TSR starting stage, the TSR and coal pyrolysis symbiotic H2S stage, and the TSR autocatalytic reaction stage. TSR reactions exhibit different reactivities under different sulfate conditions and starting temperatures. The concentrations and yields of the H2S generated by the TSR reactions of MgSO4, CaSO4 and Na2SO4 decreased successively. The stronger the electronic induction effect of a cation was, the lower the energy barrier for the TSR reaction. High salinity led to contact ion pairs (CIP) involving sulfates and then accelerated the TSR reaction and H2S generation. Smaller coal particle sizes promoted heat and mass transfer during the TSR reaction, which enhanced H2S production.

Hydrogeochemistry Study of Groundwater and Identify their Origin in the Region Surrounding of Ramadie City in Al - Anbar Province, Iraq

Hydrogeochemical study and identify the origin of water wells were curried out in the region surrounding of Ramadie city in Al-Anbar province, Iraq. Results of the study showed that the groundwater in the study area mostly is very hard and alkaline nature as hardness values ranged 324.2 to 1763.5 and as pH values ranged 7.12 to 7.81 respectively. It has conducted a test of accuracy of the chemical analysis for collected water samples and shows it's very accurate and within the permissible limits and reliable in the chemical interpretation. In the present study "Piper diagram" have been used for manipulating analytical data to estimate the chemical type of groundwater in the study area. Depending on this diagram the groundwater in the study area is considerably dominated by Sulfate type and four hydrochemical facies of water have been detected. These facies are "Na+- SO42- ", "Na+- Cl- "," Mg2+- SO42- " and " Ca2+- SO42- ". To decide the groundwater origin of hydrochemical functions such as rCa / rCl rMg / rCl, rNa / rCl, rK / rCl, and rSO4 / rCl in the studied water samples have been calculated and compared with the standard values of the seas and oceans waters. The result shows that the origin of the water in the study area is infiltrated meteoric.

Geochemistry of Brine and Paleoclimate Reconstruction during Sedimentation of Messinian Salt in the Tuz Gölü Basin (Türkiye): Insights from the Study of Fluid Inclusions

The halogenesis of the Messinian Tuz Gölü Basin corresponds to the sulfate type and the magnesium sulfate subtype. Compared to the Messinian Sea brines, they have a slightly higher [Na+] concentration, which is 96.6–116.4 g/L, and a much lower [K+] concentration, ranging from 0.1 to 2.35 g/L. During salt sedimentation, the [Mg2+] concentration ranged from 6.1 to 14.0 g/L, and the [SO42−] concentration from 18.2 to 4.5 g/L. Physical–chemical reactions in the basin’s near-surface and bottom waters during the suspension of halite deposition had a decisive influence on the significant reduction of [SO42−] sedimentation brines. During these periods, there was an intensive influx of Ca(HCO3)2 into the sedimentation basin and the formation of glauberite layers. The formation of the glauberite resulted from the slow dissolution of pre-deposited finely dispersed metastable minerals—gypsum, sodium syngenite, or mirabilite. In fluid inclusions in the halite, the sulfate minerals being allogenic crystals of calcium sulfate, are represented by gypsum, bassanite, and anhydrite. Additionally, as the other sulfate minerals, glauberite, anhydrite, and thenardite are found within halite crystals. Sharp fluctuations in daytime air temperatures characterized climatic indicators of the summer period in the Tuz Gölü region: 15.6–49.1 °C. In the spring or cool summer–autumn period, the daytime air temperature in the region ranged from 15.7–22.1 °C, and in late spring and early summer, it ranged from 20.6 °C to 35.0 °C. During some periods, the Tuz Gölü halite crystallized at 61.8–73.5 °C. The extreme high-temperature crystallization regime at the bottom of the salt-bearing basin was achieved due to the emergence of a vertical thermohaline structure. The “greenhouse effect” in the Tuz Gölü was established only briefly but was periodically renewed due to the influx of “fresh” waters.

Comparison of Two Sulfate-Bearing Soils Stabilized with Reactive Magnesia-Activated Ground Granulated Blast Furnace Slag: Swelling, Strength, and Mechanism

Sulfate-bearing soils, which causes many engineering problems, e.g., cracking, collapse, and pavement layer settlement, are often encountered in the construction of pavements. Ground granulated blast furnace slag (GGBS)-magnesia (MgO) has been regarded as an effective curing agent in the treatment of sulfate-bearing soil containing gypsum. However, field sulfate-bearing soils usually include other forms of sulfates, such as sodium sulfate (Na2SO4) and magnesium sulfate (MgSO4). Currently, few studies have investigated the effect of the type of sulfate on the properties of sulfate-bearing soil stabilized with GGBS-MgO. In this study, GGBS-MgO was used to treat Ca-sulfate-soil and Mg-sulfate-soil. Swelling, unconfined compressive strength (UCS), X-ray diffraction (XRD), and scanning electron microscopy (SEM) tests were employed to investigate the properties of the stabilized soils. The results showed that when suitable GGBS:MgO ratios were achieved, the swelling of the two types of sulfate-bearing soils could be well suppressed. However, the trend that the swelling varied with the decrease in the GGBS:MgO ratios was opposite between the two soils. The UCS of Mg-sulfate-soils was much lower than that of the Ca-sulfate-soils after the stabilization of GGBS-MgO irrespective of the curing or soaking stage. CSH significantly occurred in Ca-sulfated soils treated by GGBS-MgO. Ettringite was not observed in the soil with GGBS-MgO = 9:1 but was observed in 6:4. Compared to Ca-sulfate-soils, MSH and less CSH were formed in Mg-sulfate-soils stabilized with GGBS-MgO, which caused the lower strength of the stabilized Mg-sulfate-soils. No ettringite was formed in such soils. Hence, the sulfate type contained in the soils had a significant effect on the swelling and strength properties of sulfate-bearing soils with GGBS-MgO, and so the sulfate needs to be identified before the soil’s stabilization.

Experimental investigation on the influencing factors of preparing three-phase foam

A three-phase foam is considered one of the promising advanced materials for fighting fires. However, the preparation conditions, cost and effect are key factors for industrial applications. In this study, new three-phase foam systems with fly ash and a complex surfactant are proposed. Five types of surfactants alcohol polyoxyethylene ether sodium sulfate, coconut oil diethanolamine, sodium lauryl sulfate, polyacrylamide and polyether-modified silicone resin emulsion were selected as foaming agents. Through laboratory experiments, the effect on the expansion ratio and foam stability of the surfactant type/concentration, fly ash particle concentration/size and pH were investigated. The foaming condition was determined by numerical optimization. The results of this study may serve as a reference for understanding the preparation of a novel threephase foam. It is hoped that this work could provide useful guidance for the preparation of efficient three-phase fire-extinguishing foam for the safe guarding of process safety in the field of chemical production, transportation, and storage suitable for drug delivery than Al12P12 and Al12N12 based on their recovery times.

Istraživanja antibakterijskih svojstva tkanine od banane bojenjem prirodnim bojama

Natural fibres, which are always biodegradable, organic, and non-toxic, find wide demand in technical textiles. Banana, a cellulosic fibre acquired from the banana plant, is a natural fibre that contributes to conserving the environment. The present study envisages extracting banana fabric using natural dyes such as henna, turmeric, and indigo. The banana fabric was pre-mordanted with two types of mordants, i.e., copper sulphate and alum. The banana fabric was dyed with turmeric, henna, and indigo. The henna shows a brown colour, the indigo shows a light blue colour, and the turmeric shows a rich yellow colour. Among those three dyes, turmeric shows the best colour, i.e., a rich yellow colour, and it also shows good antibacterial properties.

Analysis of Extracellular Vesicle-Associated Proteoglycans.

Extracellular vesicles (EVs) have emerged as a central mechanism of intercellular communication in physiology and disease. EVs participate in paracrine exchange of nucleic acids as well as lipids, proteins, and glycans to elicit a complex biological response in target cells. Proteoglycans (PGs) are widely expressed in EV-producing cells and are sorted to the membrane of secreted EVs to participate in some of the key processes in EV-mediated signaling. Most notably, PGs mainly of the heparan sulfate (HS) type are involved in EV biogenesis and cellular uptake of EVs through endocytic processes. EV-associated PGs may serve as short- and long-range chaperones of signaling molecules with potential implications for intercellular information exchange, most importantly in cancer development. This motivates the development of approaches targeting EV-HSPG interactions as a strategy in cancer treatment. Moreover, the importance of PG remodeling and alterations in their expression in cancer, together with the fact that EVs mimic their cell or tissue of origin, point at an important role of EV-associated PGs as disease biomarkers. Here, we provide methodological insights into the analysis of EV-PGs isolated from cell cultures as well as patient plasma liquid biopsy.

Spatio - temporal analysis of the lakes of the Kamyshlovsky Log of the Omsk region and their impact on the soil cover

The article presents data on changes in the state of the lakes of the Kamyshlovsky Log of the Omsk region based on spatio-temporal data of satellite images and analysis of the chemical composition of water. It is shown that the sodium sulfate type of water in the lakes of the region is formed in the foci of continental salinization – in the Kamyshlovsky Log. It is shown that the decisive role in the formation of lakes is played by their feeding with groundwater enriched with sodium chlorides. The data of the spatial-temporal analysis of the lakes of the Kamyshlovsky Log indicate the course of the process of salinization in the period from 2016 to 2020. Chlorides are of decisive importance in terms of chemical composition in lakes, the type of salinity in all lakes is sulfate-chloride. The exception is Kamyshnoye Lake – according to 2016 data, the type of salinity in the lake is sulphate, which by 2018-2020 was replaced by sulphate-chloride. The soil cover is mainly represented by soils of the saline range, mainly salt marshes, near Lake Piketnoe – solonets, near Kamyshlov – lugovo-chernozem saline saline soil. The type of salinization in the presented soils is sulphate.