Foam Index Research Articles

Digital foam index for evaluating fly ash air entrainer interactions

Real-time evaluation of fly ash and air-entrainer (AEA) interaction was performed by acquiring and analyzing videos of the evolving foam layer in cement-fly ash-water mixtures using the foam index test. This modified foam index test or digital foam index, defines two fundamental parameters linked to foam generation and stability, and thus can be used to improve concrete air-entrainment for freeze-thaw durability. The AEA dosage required to produce a metastable foam is defined as foam stability dosage, whereas the incremental AEA dosage beyond the foam stability dosage to achieve a foam layer covering the entire container surface is termed foam efficiency dosage, and the summation of these dosages is the traditional foam index. The foam stability and efficiency dosages are independent parameters as a vinsol resin-based AEA had a higher foam efficiency dosage but a lower foam stability dosage than a sulfonate–based AEA.

Optimization of the alcalase and trypsin hydrolysis conditions of an isolated protein from Scenedesmus obliquus microalgae and characterization of its functional properties

This study focused on fine-tuning the enzymatic hydrolysis variables, specifically the duration and enzyme concentrations of alcalase and trypsin, for Scenedesmus obliquus protein using response surface methodology (RSM) with a central composite design (CCD). The aim was to characterize the amino acids, separate hydrolysates based on molecular weight, and assess functional activities such as antioxidant, emulsifying, fat-binding, and foaming capacities. After fractionating the hydrolysates, bioactivities were evaluated through standard assays. The optimal hydrolysis conditions—10.24 g/100 mL alcalase and 2.56 g/100 mL trypsin—yielded the highest protein extraction. Peptides smaller than 5 kDa demonstrated 80% DPPH inhibition and superior fat-binding capacity. Emulsifying capacity peaked at 112 m2/g for peptides under 10 kDa, and the highest foaming index was observed for peptides below 5 kDa. The application of RSM effectively optimized the hydrolysis of microalgal protein isolates for maximum efficiency, highlighting microalgae's potential as a sustainable source of functional ingredients.

Effect of SiO2 and Al2O3 on the Thermophysical Properties and the Foaming Index of Electric Arc Furnace Slag from the Production of Construction Steel

Viscosity, density, and surface tension of an industrial electric arc furnace (EAF) slag from production of construction steel with varying SiO2 and Al2O3 contents are investigated using a rotating viscometer and the maximum bubble pressure method. In addition, influence of thermophysical properties on foaming index is discussed. To predict the behavior of the solid phase in the slag at different temperatures, thermodynamic calculations are performed using FactSage 8.1 software. The experiments demonstratethat SiO2 and Al2O3 act as network formers in the studied slag systems, resulting in increased viscosity values in the liquid‐dominant region and decreased density of the slag. The presence of alumina and silica altered the behavior of the slag in the liquid‐dominant region, shifting the breaking point of the slags. Furthermore, the addition of silica decreases the surface tension of the slag, confirming its role as a surfactant. However, the addition of Al2O3 increases the surface tension due to the high surface tension of pure alumina. Consequently, the foaming index of the slag can increase by ≈40%, primarily due to the polymerization of the slag.

Measuring concrete air-entraining admixture adsorption on coal ash using three-phase equilibrium and fluorescence-based methods

This manuscript presents two novel methods of evaluating the adsorption of air-entraining admixtures (AEAs) by coal ashes used in cementitious mixtures. A developed three-phase equilibrium (TPE) method measures fly ash adsorption capacity accounting for carbon adsorption, Ca2+ interactions with AEA, and the equilibrium between the two. A fluorescence-based method (FBM) was also developed, utilizing a non-ionic NP-10 surfactant as a representative for AEA. This study verifies the applicability and accuracy of the TPE and FBM methods using seven class C and F coal ashes with a wide range of loss on ignition values, varying from 0.2 to 15.6 %, and three commercial AEAs. Verified with foam index test results, the TPE method was applicable to all tested AEAs and coal ashes. The results were consistent between the FBM and TPE methods when comparing rosin- and fatty acid-based AEAs, but less consistent when using a sulfonate-based AEA. These findings help us understand the applicability and limitations of the TPE and FBM methods and provide two methods for quantifying adsorption in fly ash samples.

Stability Analysis of Anionic-CO2-Soluble Surfactant Di-(2-ethylhexyl) Sodium Sulfosuccinate-Assisted Oily Foam Based on Statistical Analysis of Bubble Dynamic Characteristics.

Currently, oily foam stability in CO2 injection for heavy oil recovery exhibits inadequacies that considerably constrain its extensive application. Some scholars have conducted research demonstrating that CO2-soluble surfactants can assist in inducing heavy oil to form oil-based foams (oily foam). In this study, stability tests for the oily foam were conducted at different surfactant concentrations using a visualized PVT cell. Oily foam stability was assessed by calculating the comprehensive foam index (S) and analyzing the bubble images. The research indicates that AOT can effectively reduce the interfacial tension between oil and gas. At a concentration of 0.1 wt % AOT, the interfacial tension can be effectively reduced from 1.75 to 1.14 mN/m. The concentration of 0.3 wt % AOT represents a turning point, with an S of 16 101.7 mL·min. Beyond this concentration, the increase in S becomes less pronounced. As the concentration of CO2-soluble surfactant is increased from 0.1 to 0.5 wt %, the average bubble radius decreases from 2.74 to 0.43 mm, while the number of bubbles per unit area increases from 5.56 to 81.1 per cm2. With an increasing concentration of the CO2-soluble surfactant, the system generates more and smaller gas bubbles within the oily foam, resulting in a slower bubble coalescence. The findings of this study are poised to play a pivotal role in enhancing heavy oil recovery efficiency.

Influence of physical properties and chemical compositions of bitumen on foam characteristics

This study explores the influence of intrinsic bitumen properties on foam characteristics, considering physical properties (penetration, softening point, viscosity), chemical compositions (SARA components, FTIR indices), and physico-chemical characteristics [surface free energy (SFE)]. Ten distinct bitumen samples from two different sources were analyzed. The results reveal that physical properties alone do not sufficiently account for variations in foaming potential among bitumen types. However, chemical compositions and SFE proved to be more informative, explaining the differences in maximum expansion ratio and foam index, specifically for bitumen from the same source. In contrast, when bitumen originates from different sources, none of these intrinsic properties can clarify foaming potential. Notably, intrinsic bitumen properties fail to elucidate the variability in the half-life of foamed bitumen, even when the bitumen types share the same source. These findings underscore the significance of considering multiple factors when assessing bitumen's foam characteristics, particularly when evaluating materials from diverse sources.

CHEMICAL ANALYSIS AND BIOLOGICAL ACTIVITY OF TURKESTAN SOAPROOT ALLOCHRUSA GYP-SOPHILOIDES (REGEL) SCHISCHK GROWING IN THE SOUTH OF KAZAKHSTAN

Allochrusa gypsophiloides (Regel) Schischk. Turkestan soaproot (TSR), a Central Asian endemic has commercial value as a producer of triterpene saponins. Spectrophotometric determination of saponins was carried out in the roots and the aerial part of wild plants during vegetation in the south of Kazakhstan. The level of saponins, phenols, and flavonoids in the seeds, aerial parts, and roots was assessed. The following ascending order in the saponins content: seeds-aerial part-root, was revealed. An increase in the saponins levels in the roots during the growing season with a maximum of 9.6% in fruiting was established. A high saponins amount (6%) was detected in the aerial part during the flowering which decreased twice at the fruiting. The antioxidant activity and foaming index of the total ethanol extracts from the initial and deposited plant materials were determined. The maximum antioxidant activity (35.5%) and antiradical properties (IC50 1480) in vitro were found in extracts from the aerial part with the highest content of flavonoids and phenols. It was revealed that long-term storage of roots contributes to an increase in saponins levels and in their surfactant properties. The data obtained indicate the possibility of alternative use of the aerial parts of Allochrysa gypsophiloides at the flowering for obtaining triterpene saponins and phenolic substances with antioxidant activity.

Synergistic effects between anionic surfactant SDS and hydrophilic silica nanoparticles in improving foam performance for foam flooding

In foam flooding, foams stabilized by conventional anionic surfactants are usually raptured in contacting with crude oil, which behaves as a strong defoamer. In this article the synergistic effects between anionic surfactant SDS and negatively charged hydrophilic silica nanoparticles in stabilization of aqueous foams were examined. The results show that in either deionized (DI) water at 25 °C or Daqing simulated connate (SC) water with a total salinity of 6,778 mg/L at 45 °C, in absence of oil adding low concentration of silica nanoparticles into the SDS aqueous solutions can improve the foam performance of SDS mainly by increasing foam stability, as indicated by a synergistic effect index Se(d/s) (ratio of the composite foaming index of dispersion to that of solution) of 2.7 to 2.8. In presence of oil the foam performance of SDS in SC water at 45 °C can still be improved as indicated by an increased Se(d/s) of 3.7, but the maximum composite forming index is catastrophically reduced from 3222 Ls in absence of oil to 470 Ls in presence of oil. As similarly charged nanoparticles the silica nanoparticles do not adsorb at gas/liquid or oil/water interface to stabilize Pickering foams or Pickering emulsions but can improve emulsification of the oil, and the emulsified oil droplets together with the silica nanoparticles distribute in aqueous lamellae enhancing liquid viscosity and slowing down the liquid drainage in the foams. However, this effect weakens at high surfactant concentration, and addition of silica nanoparticles does not significantly reduce the interfacial tensions involved. The Enter (E), Spreading (S) and Bridging (B) coefficients of the oil in the foam systems are therefore still positive. The defoaming action of the oil in this system is not eliminated by only partially inhibited by addition of silica nanoparticles.

Foaming Properties of Lignosulfonates in the Flotation Process.

The widely used technology for the selective flotation of copper and molybdenite using sodium hydrosulfide (NaSH) to depress copper sulfides creates environmental issues related to the potential emissions of toxic hydrosulfide gas (H2S) and bad odors. Previous studies showed that molybdenite flotation can be depressed by the action of lignosulfonates, but no significant progress has been made in studying the effect that these reagents have on the foaming/frothing phenomena in flotation. The objective of this work was to investigate the foaming properties of three samples of lignosulfonates through measurements of surface tension, foamability, bubble size distributions, and water recovery. A sugared sodium lignosulfonate (NaLS), a calcium lignosulfonate (CaLS), and a sample prepared by sulphomethylation of kraft lignin (KLS) were tested. It was found that all lignosulfonates displayed surface activity that decreased with pH and was related to the degree of anionicity and molecular weight. The NaLS lignosulfonate showed the highest dynamic foamability index (DFI) value, compared to that of the CaLS and KLS samples. The lignosulfonates tested in this study strongly affected bubble size. Water recovery tests performed using flotation experiments in a two-phase system showed that the KLS and NaLS samples had the strongest effect, which correlated with the surface tension, foamability, and bubble size results.

Influences of admixture combinations on the formation and stability of air bubbles in fresh cementitious materials

Various mineral and chemical admixtures have been widely added to modern concrete mixtures but few studies have investigated the characteristics of air bubbles in fresh cementitious materials under different admixture combinations. This study aimed to explore the influences of mineral and chemical admixture combinations including one Class F fly ash, three different air entraining admixtures (AEAs), and two various polycarboxylate superplasticizers (SPs) on the formation and stability of air bubbles in fresh cementitious systems. The foam index tests on fresh cementitious paste were utilized to explore the impacts of fly ash, AEA types, and SP on foam ability. Also, twelve fresh concrete mixtures were produced in laboratory, then the air volume content and air bubble spacing were measured within 60 min to assess the air bubble stability. Test results suggested that adding fly ash decreased the foam ability of AEA, while the SP addition improved the foam ability. The neutralized vinsol-resin based AEA1 had a higher foam ability than synthetic AEA2 and AEA3. The foam index of paste with SP addition showed a higher correlation with the AEA dosage for fresh concrete than those without SP addition. The air bubble stability in fresh concrete was highly affected by the admixture combinations. Overall, neutralized vinsol-resin based AEA1 produced more stable air bubbles than synthetic AEA2 and AEA3.

Characterization of crude saponins from stem bark extract of Parinari curatellifolia and evaluation of its antioxidant and antibacterial activities

Abstract Saponins are surface active glycosides which occur in plants as one of the secondary products of primary metabolism. Saponins have been reported to demonstrate antimicrobial, antioxidant and other biological activities. This study was designed to characterize the crude saponins extracted from stem bark of Parinari curatellifolia and to study the antibacterial and antioxidant activities. The saponin was extracted using standard protocol and was subjected to physicochemical characterization. Foaming and haemolysis tests as wells as determination of foaming index were conducted to confirm the presence of saponins. The solubility of the crude saponins was tested in various organic solvents at room temperature. The nature of the aglycone moiety was identified using Salkowski’s and Liebermann–Burchard’s tests. The glycone moiety was identified using Fehling’s test. Fluorescence test was conducted using UV light at 254 and 366 nm. The TLC separation profile was determined in suitable solvent system. The saponin was subjected to UV and FTIR finger printings using standard methods. Silver nanoparticles were synthesized and characterized using standard method. The saponins were evaluated for antioxidant and antibacterial activities using standard procedures. The foaming index was found to be 1666.6. The crude saponin showed different degrees of solubility in the solvents tested and was found to be highly soluble in methanol, ethanol and DMSO. Generally, the saponins were found to be insoluble in non-polar solvents. The aglycone moiety was found to be triterpenoidal in nature and the glycone was found to be a reducing sugar. The crude saponin produced fluorescence at 254 nm which indicated the presence of some chromophores. The TLC showed the presence of some metabolites with varying Rf values. The UV analysis revealed two absorption peaks at 480 nm and 580 nm. The FTIR finger printing showed absorptions characteristic of some functional groups at different frequencies. The crude saponin and silver nanoparticles demonstrated free radical activity against DPPH free radical with IC50 of 5.878 mg/mL and IC50 0.2477 mg/mL, respectively while the H2O2 radical had IC50 of 5.750 mg/mL. The saponin inhibited the growth of Staphylococcus aureus with zone diameter of inhibition between 2 and 3 mm. The saponins are triterpenoidal in nature and demonstrated antioxidant and antibacterial activity.

High-Performance Thin Layer Chromatography Method Development to Estimate Phytoconstituents in Hedychium species

Objective: The H. coronarium (Zingiberaceae) is a perennial herbaceous plant. Chinese immigrants introduced the H. coronarium species as an ornamental plant in 1888. Its attractive fl owers make it a desirable ornamental plant. The present study aims to evaluate the physiochemical characteristics and development of the (HPTLC) Fingerprint sequence profi le of Hedychium coronarium leaves. Method: Pharmacognostic characteristics and physiochemical parameters were performed according to the method prescribed. The mobile phase confi rmation was completed using by performing (TLC). The development of the HPTLC fi ngerprint was performed with some modifi cations to get exact separation of phytochemicals using mobile phases such as Toluene: chloroform: ethanol (4:4:1). Result: Pharmacognostic study reported the presence of unicellular trichomes, vessels, epidermal cells, oil globules, and vascular bundles. Pharmacognostic and physiochemical parameters like color, nature, odor, taste, foreign organic matter, loss on drying, ash value, extractive value, and the foaming index were found to be satisfi ed as documented in the results. The HPTLC fi ngerprinting reveals the presence of various chemical compounds expressed as Rf value. Conclusion: From current scientifi c research work, Hedychium coronarium can be useful in modern medicine as various bioactive secondary metabolites were detected.

Effect of high γ-irradiation dosage on physico-chemical, functional and emulsion properties of almond gum powder

Almond gum is a natural biopolymer produced by Almond tree that is non-toxic, biodegradable, and biocompatible. These features make it suitable for applications in the food, cosmetic, biomedical, and packaging industries. To ensure its wide application in these fields, green modification process is necessary. Gamma irradiation is often used as a sterilisation and modification technique, due to its high penetration power. Thus, evaluating its effects on the physicochemical and functional properties of gum after exposure is important. To date, limited studies have reported the use of high dose of γ-irradiation on the biopolymer. Therefore, the present study demonstrated the effect of a high dose of γ-irradiation (0, 24, 48, and 72 kGy) on the functional and phytochemical properties of almond gum powder. The irradiated powder was studied for its color, packing, functional, and bioactive properties. The results revealed a significant increase in water absorption capacity, oil absorption capacity, and solubility index. However, a decreasing trend was observed in the foaming index, L value, pH, and emulsion stability with the radiation dose. Besides, sizable effects were observed in the IR spectra of irradiated gum. Phytochemical properties were significantly improved with an increase in dose. The emulsion was prepared from irradiated gum powder, where the highest creaming index was observed at 72 kGy and a decreasing trend in zeta potential. These results suggested that γ-irradiation treatment is a successful method to generate desirable cavity, pore sizes, functional properties, and bioactive compounds. This emerging approach could modify the natural additive with distinct internal structure for specific uses in wide range of food, pharmaceutical and other industrial applications.

Phytochemical Investigation of Tectona Grandis Lin. by different Solvent Fractions

Abstract: The objective of the present work is to carry out the phytochemical screening of different fractions obtained from methanolic extract of Tectona grandis leaves. Physicochemical analysis was done to determining total ash, acid insoluble ash, water soluble ash, sulphated ash, extractive value, moisture content, crude fiber content and foaming index. Phytochemical investigations were carried out on different fractionto determine various active constituents present in it by using standard preliminary phytochemical tests. The inorganic element, such as calcium, magnesium, sodium, potassium, iron, copper, zinc and manganese were found in the extract of leave Florescence analysis of the fractions were reported which gives the sensitivity of the chemical in different chemical reagents. Preliminary phytochemical screening of different fractions of Alcoholic extract showed the presence of the phytoconstituents like alkaloids, glycoside, proteins and amino acid, carbohydrates, flavonoids, terpenoids, tannins, saponins and sterols.

Chemical and Foaming Analysis on Cold Mix Asphalt Performance with Recycled Asphalt Pavement

Cold-mix asphalt has been developed in recent years by combining foamed asphalt and recycled asphalt pavement (RAP). However, manufacturers struggled due to the less standardized specification. Foaming and mixing performance cannot be accurately controlled and are usually treated with a foaming agent (FA). This research focused on the relationship between the chemical composition of bitumen and its foaming properties. Three groups of AC-20 bitumen and organo-modified siloxanes based FA with water content of 1.5%, 2.0%, 2.5%, 3.0%, 3.5%, 4.0% and 4.5%. were analyzed. Chemical components of different bitumen types were evaluated using the Gaestel colloidal index (CI). The half-life (HL), expansion ratio (ER), Foam index (FI), and bubble surface area index (SAI) were used to evaluate the workability of the binders and discuss the effects of the values on the performance of the mixture. The CI observation revealed that FA obviously changed the saturates value and greatly improved the foam properties in terms of stability and expansion. FI change was found to be 71% of the change in the CI. Similarly, the resulting FI and SAI reach up to 88% in terms of correlation.

Compatibility of carbon nanotubes in concrete with air entrainer and superplasticizer

Multi-walled carbon nanotubes (MWCNTs) have great potential to improve performance of cementitious material in terms of mechanical, durability and electrical. This study quantitatively investigates the compatibility between MWCNTs, admixtures of superplasticizer and air entrainer (AE) in concrete materials, by performing experimental tests of surface tension, foam index and air content. Through applying various combination of admixtures and MWCNTs in concrete samples, the study finds that for concrete with MWCNTs, superplasticizer and air entrainer (AE), the surface tension, foam index, and air content could decrease up to 33%, 42%, 60%, respectively, and this significant change of air system can damage concrete freeze–thaw resistance. The significant decrease of air void content indicates the interaction between carbon nanotubes, superplasticizer and air entrainer. This interaction is further verified considering various levels of water/cement ratio or different brands of air entrainer. The study discovered the potential conflict during the application of nano materials and traditional admixtures and focused on much complicated concrete material.

Quantitative Determination of Metabolites of Turkestan Soaproot (Allochrusa gypsophiloides (Regel) Schischk.) Grown in Kazakhstan

Allochrusa gypsophiloides (Regel) Schischk. (Caryophyllaceae Juss.), Turkestan soaproot (TSR) is a super producer of triterpene saponins with a wide spectrum of pharmacological activity and high surface-active properties. The realization of his full commercial potential requires biochemical studies with a focus on the metabolites dynamics at various phases of plant development and in connection with the storage duration of raw plant material. Spectrophotometric determination of saponins in terms of oleanolic acid was carried out in roots with different morphometric parameters and the aerial part from wild plants collected in the south of Kazakhstan. The content of saponins, carbohydrates, phenols, and flavonoids as well as the foaming properties of ethanol extracts obtained from air-dried TSR roots before and after their long-term storage were evaluated. The maximum quantity of saponins was revealed in average roots from middle-aged and mature generative plants in fruiting. A high level of saponins was detected in the aerial part of plants during the flowering, which decreased twice at the fruiting stage. After long-term storage of the roots, an increase in the initial content of saponins and flavonoids combined with a decrease in carbohydrates was noted. Saponins accumulation was confirmed by a 12-fold increase in the foaming index in the aqueous extract from the deposited roots relative to its initial value in the extract from the original roots. The data obtained indicate the possibility of alternative use of the aerial part of the original plants of A. gypsophiloides at the flowering stage to obtain triterpene saponins.

Functionality of glycomacropeptide glycated with lactose and maltodextrin.

The Maillard reaction (MR), under proper environmental conditions, has been used to improve protein functionality. In the present work, 2 high temperatures (50-80°C) and water activity (Aw; 0.45-0.67) were used to promote exogenous glycosylation of glycomacropeptide (GMP) while minimizing processing times (0, 8, 24, 48, and 96 h at 50°C; 0, 2, 4, 8, and 24 h at 80°C). Maltodextrin, a polysaccharide commonly used in the food industry as a functional ingredient, was used as a reducing sugar, and compared with lactose, a native milk sugar. The progression of MR was evaluated by tracking changes in molecular weight using SDS-PAGE, the formation of Amadori compounds, and browning. Aqueous glycosylated GMP solutions (5 to 20% wt/vol) were tested for solubility, rheological properties, and foam formation. As expected, MR progression was faster with Aw = 0.67 and 80°C. Glycosylated GMP powders showed no change in their solubility after MR. However, the apparent viscosity (γ˙=30s-1) of the 20% wt/vol suspensions exhibited a slight increase when GMP was glycosylated with maltodextrin for 24 h at 80°C, and a 2-log increase when GMP was glycosylated with lactose, with a high browning development in both cases. The foam expansion index of the resuspended glycosylated powders was increased by between 25 and 66% compared with the nonglycosylated powders. Better foam stability (approximately 2 h) and no browning development were observed for GMP glycosylated with maltodextrin for 2 h at Aw = 0.67 and 80°C. The results show that GMP has undergone further glycosylation by means of controlled MR, which improves viscosity and foaming index without negatively affecting solubility. These preliminary studies provide a basis for the future creation of a new ingredient with GMP and reducing sugars.

Wet storage effects on fly ash properties relevant to its use in air-entrained concrete

With the retirement of coal-fired power stations, wet-stored stockpile fly ash is increasingly receiving attention for use in concrete. An important consideration for dry fly ash in this application is its impact on air entrainment, which can be affected by unburnt carbon present, influencing bubble stability and air-entraining admixture (AEA) dose requirements. Preliminary tests suggest wet storage can influence the process and the present study examined this for laboratory-moistened and stockpile fly ashes. The research indicated that chemical processes lead to product formation on particle surfaces and increases in loss-on-ignition in the material. Agglomeration of fly ash also occurred with wet storage, developing with time. While median particle size and specific surface area (by nitrogen (N2) adsorption) of fly ash increased, both foam index and Acid Blue 80 adsorption were less with wet storage. Mortar tests mainly gave increased air content at fixed AEA dose for material held under these conditions. The data suggest admixture accessibility to wet-stored fly ash particles influenced behaviour and this increased with the breakdown of particle agglomerates (by grinding). Some influences of particle surface chemistry on the process were also found. A pilot-scale processing trial with stockpile fly ash gave general agreement with effects observed in the laboratory.

Influence of pH‐value and ionic concentration on the dynamic foamability index of flotation frothers

Influence of pH‐value and ionic concentration on the dynamic foamability index of flotation frothers