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The formation of AlN/AlGaN short period superlattices (SPSLs) was investigated though the introduction of a constant Ga overpressure during the metal modulated epitaxy (MME) growth of AlN. A combination of x-ray diffraction (XRD) and scanning transmission electron microscopy (STEM) analyses found that control over the Al composition in the AlGaN layer was achieved through modulating the Ga beam equivalent pressure (BEP), with a minimum partial pressure of 3 × 10−7 Torr needed for Ga to incorporate at a growth temperature of 825 °C. A minimum Al composition in the AlGaN layer of 72% was achieved for a Ga BEP of 1 × 10−6 Torr using this method. An apparent limit of the AlGaN layer thickness of 3–4 ML indicated that the incorporation of Ga was confined to the consumption region of the MME growth process. Determination of this behavior made clear the requirements of having both XRD and STEM in order to be able to fully characterize the SPSL layer structure. Finally, AFM imaging highlighted that the presence of Ga on the surface behaved as a surfactant, with a minimum RMS roughness of 0.46 nm achieved at the maximum Ga BEP of 1 × 10−6 Torr. [ABSTRACT FROM AUTHOR]

In this study, semiconductive poly (lactic acid) (PLA)/carbon nanotube (CNT) nanocomposites have been simultaneously subjected to melt-compounding and foaming using a continuous and single-step extrusion foaming process. The extrusion foaming process with the ability to be developed on an industrial scale is a complex process for a biopolymer in the presence of nanoparticles, chemical foaming agent, and chain extender, and to control it, knowledge about the phenomena occurring during the process and the structural properties of the foam is required. Although the extrusion foaming of PLA has been studied before, the simultaneous effects of chain extender content and nanoparticle loading on the microstructure and phenomena during the PLA extrusion foaming process have not been thoroughly investigated. The results of this study show that the two investigated variables have a strong interaction with each other. Increasing the chain extender content has led to a change in the rheological properties of the melt, as a result, it has been significantly effective in the nanoparticle dispersion state. Besides, the loading of nanoparticles has a powerful effect on the intensity of the chain extension reaction of PLA chains by the chain extender additive. The lightest extruded foams (with a void fraction of 0.52) with the highest cell density (5 × 106 cells/cm3), the smallest cell size (about 50 and 200 µm for number- and volume-average cell diameters), and the most uniform cell size distribution have been obtained in the middle values of the chain extender content (5 phr) and the lowest values of the nanoparticle loading (0.25 phr). [ABSTRACT FROM AUTHOR]

Lipid-based foam systems (LBFs) have grown in popularity recently because of their effectiveness and potential uses. As a result, in order to stabilize them, considerable work has been put into developing more biodegradable and environmentally friendly materials. However, the use of natural stabilizing agents has been constrained due to a lack of thorough knowledge of them. This review offers insightful data that will encourage more studies into the development and use of LBFs. Emulsifiers or gelling agents, as well as new preparation and characterization methods, can be used to increase or prolong the functional performance of LBFs. Special emphasis has been given on the connections between their structures and properties and expanding the range of industries in which they can be applied. In conclusion, it is crucial to gain a deeper understanding of the preparation mechanisms and influencing factors in order to improve the quality of foam products and create novel LBFs. [ABSTRACT FROM AUTHOR]

We present here a passive and label-free droplet microfluidic platform to sort cells stepwise by lactate and proton secretion from glycolysis. A technology developed in our lab, Sorting by Interfacial Tension (SIFT), sorts droplets containing single cells into two populations based on pH by using interfacial tension. Cellular glycolysis lowers the pH of droplets through proton secretion, enabling passive selection based on interfacial tension and hence single-cell glycolysis. The SIFT technique is expanded here by exploiting the dynamic droplet acidification from surfactant adsorption that leads to a concurrent increase in interfacial tension. This allows multiple microfabricated rails at different downstream positions to isolate cells with distinct glycolytic levels. The device is used to correlate sorted cells with three levels of glycolysis with a conventional surface marker for T-cell activation. As glycolysis is associated with both disease and cell state, this technology facilitates the sorting and analysis of crucial cell subpopulations for applications in oncology, immunology and immunotherapy. [ABSTRACT FROM AUTHOR]

The objective of the proposed investigation is to examine the influence of cationic, anionic, and neutral surfactants on the Cu(II) facilitated L-Phenylalanine (Pheala) oxidation using chromic acid. The oxidation rate is ascertained by measuring the decrease in absorbance at a wavelength of 350 nm, which is an indicator of the Cr(VI) concentration. The reaction's advancement is assessed employing the pseudo-first-order condition as a gauge for [H+], [Cr(VI)], ionic strength, [Pheala], [Cu(II)], [Surfactant], and temperature. Pheala and Cr(VI) interact stoichiometrically in a ratio of 3:2. Across the spectrum of concentrations examined, the studied reaction reflects fractional-first-order kinematics in relation to both [Pheala], and Cu(II), first-order reliance on the [Cr(VI)], and fractional-second-order for [H+]. A zero salt effect is suggested by the observed constancy in oxidation rate with the inclusion of electrolyte. The oxidation rate is 3.5 times enhanced by Cu(II) solution (as a catalyst) at ppm concentration. SLS micellar media enables a further twofold increase in the rate of Pleala oxidation. TX-100 also promotes Pheala oxidation, however, CTAB, a cationic surfactant, inhibits it. As a catalyst, SLS exhibits the best compatibility with Cu(II) metal salt. [ABSTRACT FROM AUTHOR]

Ethanol is considered a clean, cost-effective, carbon-neutral fuel. In this study, the effect of a surfactant (Span 80/Tween 80) and cosolvent (furan) on the macroscopic and microscopic mutual solubility characteristics of diesel-ethanol blending were assessed. At the macroscopic level, the study investigated the impact of compound emulsifier proportions and ethanol volume ratio on the stability of the diesel-ethanol fuel. At the microscopic level, the conductivity and particle size of the blended fuels were analyzed. Additionally, fuel properties such as lower heating value, viscosity, and price per unit volume of fuel were investigated. The results indicated that Span 80 and furan were more effective in enhancing the mutual solubility of diesel and ethanol, reducing the maximum dosage by 98.55% and 92.24% by volume, respectively. Besides, compared with furan-diesel-ethanol, emulsifiers increased the conductivity of the mixture by two orders of magnitude. Furthermore, the lower heating value (LHV) of microemulsion produced by Span 80 showed the LHV closest to that of diesel and the cost was even cheaper. Considering the effectiveness of cosolvents and surfactants in stabilizing diesel-ethanol blends and their resulting fuel properties, diesel-ethanol-Span 80 stands out as a promising option for diesel engine applications, showcasing the renewed relevance of traditional emulsifiers in diesel-ethanol blends. [ABSTRACT FROM AUTHOR]

Foam is widely used in soil conditioning during EPB shield tunnelling to ensure the efficiency and safety of face support and muck flow. Currently, the concentration of the foaming agent solution is chosen based on the recommendations of foaming agent suppliers, the half-life time of foam or the properties of the foam-soil mixture. This paper studies the foaming agent concentration (Cf) choice taking surface tension into consideration. Test results show that the Cf should be higher than the critical micelle concentration (CMC) to offset the influence of the expanding surface area during foam generation in shield tunnelling. The comparison between the capillary rise method and the platinum plate method shows that this offset can almost be accomplished when Cf is higher than 1% and fully accomplished when Cf is higher than 3%. Foam generation tests show that despite the differences in foam generation methods, the foaming ability of foaming agent solution and the stability of the generated foam are close to optimum at Cf of 1% and reach optimum at Cf of 3%. Slump tests show that foam with Cf lower than 1% is not stable enough in the foam-sand mixture for shield tunnelling. Both slump tests and field validation show that when Cf is higher than 3%, the increase of Cf has limited influence on soil conditioning performance. [ABSTRACT FROM AUTHOR]

Over the past few decades, researchers have focused on developing new compositions and preparation techniques for geopolymers, as multifunctional products, to optimize their characteristics for use in multiple applications. Therefore, this paper investigates metakaolin geopolymer foam and introduces new geopolymer foams based on hybrid metakaolin and wollastonite mineral precursors for water purification. The geopolymer foams were prepared using an alkaline activator, mineral-based powders (wollastonite and metakaolin), a foaming agent (aluminum powder), and a foam stabilizer (olive oil). In addition to mechanical tests and assessments of the adsorption capacity of heavy metal ions, the geopolymer foams were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The geopolymer foams exhibited unique pore structures, containing four classes of pore networks with diameters around 1000 µm, 25 µm, 3 µm, and a well-arranged mesopore network of 50 nm. The utilization of wollastonite (CaSiO3) alongside metakaolin as a hybrid precursor led to fundamental changes in the composition of the geopolymer binders: a new crystal phase, Ca5(SiO4)2(OH)2, was formed, and the Si-Al-Na crystal phase disappeared, which led to an increase in the amorphous phase from 87% to 92%. The adsorption rate of heavy metal ions, namely Cr, Co, Cu, Zn, Pd, and As, increased upon introducing wollastonite as a precursor, with absorption rates ranging from 11% to 68%. The findings also revealed that wollastonite significantly increased the geopolymers foams' compressive strength and elastic modulus from 30 KPa to 67 KPa and from 31 MPa to 126 MPa, respectively. [ABSTRACT FROM AUTHOR]

In hospitals, IV bags can be prepared in advance for logistical and microbial safety reasons in a compounding unit and then transported to wards. Transport of protein drugs using a pneumatic tube system has been reported to result in high particle levels. In this study, pneumatic tube transport of trastuzumab in saline polyolefin bags was compared to delivery by hospital porters using an electric platform truck in an underground tunnel system. The transport was tracked using designed smart labels. Two strategies to prevent particle formation, removing headspace and adding the surfactant polysorbate 20 were evaluated. The transport by pneumatic tube had a higher level of shock and vibration than truck delivery. The total particle count measured using flow microscopy also increased more for pneumatic transport than for transport by vehicle. Removing the headspace decreased particle formation for both transports. Surfactant decreases particles over 10 µm for trastuzumab in saline IV bags but increases the total particle levels. Pneumatic tube transport of saline in polyolefin bags resulted in high particle levels and surfactant increased the total particle count. Removing headspace is a measure that can be incorporated into compounding practices to cover for inadequate surfactant levels in IV bags. [ABSTRACT FROM AUTHOR]

In this paper, the effect of surfactant type (cationic, anionic, nonionic, and zwitterionic) on the detachment of hexadecane droplets from the quartz surface was investigated. The results indicated that the oil detachment performance was controlled by the adsorption behavior of surfactant molecules at the interface between the solid and liquid phases, which could alter the solid–liquid interfacial tension (IFT). In the cationic solution, IFTs of solid-oil and solid-water decreased and increased, respectively, ascribed to the electrostatic attraction occurring between the positively charged hydrophilic group and the negatively charged quartz surface. Conversely, in the anionic solution, the anionic surfactant with a negative head group increased the oil-solid IFT because of its electrostatic repulsion with the quartz surface, increasing the oil contact angle and subsequently oil droplet detachment under the hydrodynamic effect. In addition, the results obtained from the adhesive force test showed that nonionic and zwitterionic surfactants had the capability of preventing the re-adhesion of solid and oil, whereas the anionic surfactant had the best performance among the four types of surfactant for oil detachment from quartz surface. [ABSTRACT FROM AUTHOR]

Rubber tends to adhere to molds during production due to its high viscosity at elevated temperatures, affecting product quality. The use of release agents facilitates the removal of rubber from molds, enhancing production efficiency and extending mold lifespan. With increasing emphasis on environmental protection, development and selection of high-performance, eco-friendly release agents have become pressing issues. This paper reviews recent advancements in rubber release agents, highlighting common features and selecting suitable surfactants for water-based, eco-friendly release agents. The study presents our recent progress in rubber release agents, comparing different surfactants used to formulate release agents. Particle size tests, emulsion stability tests, and release effect tests during tire production demonstrated promising results. [ABSTRACT FROM AUTHOR]

Objective: The prevention and treatment of burn wounds has improved over the years, leading to decreased incidence, severity and mortality. However, burn injuries, particularly partial-thickness burns, have a painful treatment course which, if not optimised, can cause undue suffering to patients and prolonged recovery. Although silver sulfadiazine has been the most commonly accepted treatment for partial-thickness burns due to its strong hindrance of infection, wide availability and low cost, it requires daily dressing changes which are labour intensive and painful. Exploring alternative techniques, such as using cultured keratinocytes, to prevent and treat burn wounds may provide a path to better optimising the path to recovery. Method: This paper presents two cases that use two alternative treatments, either PluroGel (a gel surfactant, Medline Industries, US) or cultured keratinocytes, in the treatment of partial-thickness burns to minimise pain and enhance treatment experience. Results: Using surfactant-based treatments, such as the gel surfactant, in partial-thickness burns exhibited prohealing outcomes via enhanced antimicrobial effects, a strengthened physical barrier and cell salvage. Conclusion: Using cultured keratinocytes and a highly concentrated surfactant may achieve more rapid re-epithelialisation of partial-thickness burn wounds. These alternative techniques may offer significant advancement in the quality of care in burn injury treatment. [ABSTRACT FROM AUTHOR]

Foam, as a gas‐in‐liquid colloid, has a higher appearance viscosity than the one of both gas and liquid that form it. Adjusting the mobility ratio of the injected fluid–oil system and increasing gas diffusion in the foam injection process increase oil production. With these properties, foam as an injection fluid in fractured reservoirs has a major effect on oil production from the matrixes and prevents premature production of injection fluid. Surfactants are common foaming agents in injection water. Saponins are known as plant‐derived surfactants for forming stable foam. This feature, along with its cheap price and availability, can make them candidates for enhanced oil recovery (EOR) by the foam injection method. However, the utilization of CO2 as the gaseous phase in foam introduces additional machanisms of CO2 injection to the oil recovery operations. In this assessment, a non‐ionic green surfactant derived from the Anabasis setifera plant was used as a foaming agent, while CO2 served as the gas phase. A series of surface tension tests in CO2 environment were performed to determine the optimal concentration of the surfactant. Foaming tests were performed by a designed foam generator. The produced CO2‐foam was then injected into a fractured carbonate plug with six matrixes (with one horizontal and two vertical fractures). Based on the results, the water–CO2 surface tension was reduced to 20.549 mN/m. The optimum salinity based on the foam stability was 10,000 ppm. The half‐life of the foam was determined to be 40 min. Also, the foam characterization showed that the foamability of the surfactant was favourable for increasing oil production so that by secondary flooding, an oil recovery of more than 66% was achieved from the fractured carbonate plug. [ABSTRACT FROM AUTHOR]

In this study, a new type of thermal insulation protective material with good thermodynamic properties was successfully prepared. Using boron hybrid silicone rubber (B-SR) as matrix and hollow ceramic microsphere (HCM), hollow silica microsphere (HSM) and hydroxy silicone oil foaming agents (OH-3#) as thermal insulation phase, a single thermal insulation phase (HCM/B-SR, HSM/B-SR, OH-3#/B-SR) was prepared, and the influence of single thermal insulation function on the performance of thermal insulation material was studied. Based on the influence of single thermal insulation function phase on the performance of thermal insulation material, orthogonal experiment was designed to study the influence of composite thermal insulation function phase on the performance of thermal insulation material. The influence of single and composite thermal insulation function phase on thermal performance and mechanical properties of insulation materials were studied by scanning electron microscopy, thermogravimetric analysis plate thermal conductivity meter and universal testing machine, respectively. Through the orthogonal design experiment and further optimization, the final formula of boron hybrid silicone rubber-based thermal insulation protection material was obtained. When B-SR: HCM: HGM: OH-3# = 100: 15: 25: 18, the comprehensive performance of multiphase composite insulation materials was the best. The results showed that the thermal conductivity of the thermal insulation material under the formula is 0.064 W/(m K), T10 is 549.9 °C, Tmax is 621.3 °C, R1000 is 77.5%, tensile strength is 2.43 MPa, elongation at break is 73.6%, compression modulus is 11.7 MPa, hardness is 43°. The good synergistic effect of different thermal insulation function phases ensured the technical requirements of warhead thermal insulation protection materials for low thermal conductivity, high heat resistance and structural strength to the greatest extent. This study is of great significance for preparing highly efficient thermal insulation materials through the organic combination of HM filling and chemical foaming. [ABSTRACT FROM AUTHOR]

AbstractThe purpose of this work was to create and assess Lornoxicam (LOR) loaded Novasomes (Novas) for the efficient treatment of ulcerative colitis. The study was performed using a 23 factorial design to investigate the impact of several formulation variables. Three separate parameters were investigated: Surface Active agent (SAA) type (X1), LOR concentration (X2), and SAA: Oleic acid ratio (X3). The dependent responses included encapsulation efficiency (Y1: EE %), particle size (Y2: PS), zeta potential (Y3: ZP), and polydispersity index (Y4: PDI). The vesicles demonstrated remarkable LOR encapsulation efficiency, ranging from 81.32 ± 3.24 to 98.64 ± 0.99%. The vesicle sizes ranged from 329 ± 9.88 to 583.4 ± 9.04 nm with high negative zeta potential values. The release pattern for Novas’ LOR was biphasic and adhered to Higuchi’s model. An in-vivo study assessed how LOR-Novas affected rats’ acetic acid-induced ulcerative colitis (UC). The optimised LOR-Novas effectively reduced colonic ulceration (p < 0.05) and reduced the inflammatory pathway via inhibiting Toll-like receptor 4 (TLR4), Nuclear factor kappa β (NF-κβ) and inducible nitric oxide (iNO). At the same time, it elevated Silent information regulator-1(SIRT-1) and reduced glutathione (GSH) colon contents. Thus, the current study suggested that the formulation of LOR-Novas may be a viable treatment for ulcerative colitis. [ABSTRACT FROM AUTHOR]

Improving the stability of CO2 foam is a core concern in CO2 foam flooding oil recovery technology. Using hydrophobic nano‐SiO2 to enhance the stability of CO2 foam is a common approach, but hydrophobic nano‐SiO2 faces challenges, such as easy aggregation, difficult dispersion, and performance needs to improve. In this article, a novel dispersion of styrene‐phenylamine monomer copolymer (PSSN) nanosphere with primary amine groups on the surface was synthesized. The synthesis conditions of PSSN were optimized, and its performance for stabilizing CO2 foam was evaluated. The experimental results demonstrated that PSSN had better performance for stabilizing CO2 foam than that of hydrophobic nano‐SiO2 when using cocamidopropyl betaine (CAB) as the foaming agent. With the CAB concentration of 4000 mg/L and PSSN concentration of 100 mg/L in the brine having salinity of 8460 mg/L, the half‐life of CO2 foam at 90°C was 131 min, which was 43 min longer than that stabilized by hydrophobic nano‐SiO2 under the same conditions. This is for the first time that polystyrene microspheres with amine groups on the surface was used to stabilize CO2 foam. The study provides a new nanoparticle option for stabilizing CO2 foam. [ABSTRACT FROM AUTHOR]

Low toughness and brittleness limit its application range of thermosetting epoxy resin (EP) based foams. In current research, inorganic particles are commonly utilized as heterogeneous nucleating agents to enhance foaming quality and EP toughness. However, the increasing inorganic particle content usually leads to particle agglomeration, which negatively impacts foaming quality and reduces EP performance. Block copolymers, which appear as liquid to effectively mitigate agglomeration, are employed as toughening materials for EP. In this study, a small number of modified calcium silicate particles (MCS) were used as anchor points to induce the distribution of block copolymers (P‐F68) to improve EP toughness and effectively enhance cell nucleation, thus, EP/MCS/P‐F68 foams performance was improved. The research results showed that EP foams obtained excellent cell structure and very small foam density (0.256 g/cm3) at the P‐F68 content of 10 wt%. The continuous increase of P‐F68 content would lead to the thickening of cell wall and the increase of cell size. Simultaneously, the core‐shell structure formed by P‐F68 in EP effectively enhanced the toughness of EP foams and mitigated its brittleness, offering crucial theoretical guidance for toughening and regulating the cell structure of EP foams. [ABSTRACT FROM AUTHOR]

AbstractThis study evaluated albendazole (ABZ) nanostructured lipid carriers (NLCs) for hepatocellular carcinoma treatment. ABZ-NLCs were prepared using emulsification-ultrasonication and optimised using a Box-Behnken design. Independent variables—lipids concentration (X1), surfactant concentration (X2), and sonication duration (X3)—were assessed for their effect on mean diameter (Y1), PDI (Y2), and entrapment efficiency (Y3). The optimised formulation exhibited a mean diameter of 166.13 ± 3.72 nm, a PDI of 0.17 ± 0.01, a zeta potential of −39.86 ± 1.84 mV, an entrapment efficiency of 94.25 ± 6.12%, and a loading capacity of 99.93 ± 7.15 mg/g. Following chitosan coating (ABZ-CS-NLCs), all parameters were maintained, and the zeta potential developed to +24.61 ± 1.32 mV, improving cellular interaction. The cytotoxicity assays revealed that ABZ-CS-NLCs were more effective than uncoated NLCs and free ABZ, with an IC50 value of 8.89 μM in HepG2 cells. Overall, ABZ-CS-NLCs demonstrate a promising and effective delivery platform for targeted hepatic cancer therapy. [ABSTRACT FROM AUTHOR]

High-Density Polyethylene (HDPE) and Low-Density Polyethylene (LDPE) films were used to create nanoplastic (NP) models, with the shape of delamination occurring during degradation. In the case of HDPE, selective degradation occurred not only in the amorphous part, but also in the crystalline part at the same time. Some of the lamellae that extend radially to form the spherulite structure were missing during the 30-day degradation. The length of these defects was less than 1 µm. HDPE disintegrated within units of spherulite structure by conformational defects in lamellae, and the size of the fragments obtained had a wide distribution. LDPE was synthesized by radical polymerization, so it contained a cross-linked part. The part was not sufficiently fused, and when it degraded, it delaminated and separated preferentially. The zeta potential reached a minimum value of approximately −20 mV at the degradation time of 21 days, and then increased. This complex dependence on degradation time was due to NP particle aggregation. The addition of 1% Triton(R) X-114 surfactant was effective in stabilizing the NP dispersion. The particle size remained constant at around 20 nm for degradation times of 15–30 days. [ABSTRACT FROM AUTHOR]

In organic synthesis, the solvent is the chemical compound that represents the largest proportion of the process. However, conventional solvents are often toxic and dangerous for the environment, and an interesting alternative is to replace them by water. In this context, catalyst surfactants allow both organic reagents in water to be solubilized and organic reactions to be catalyzed. This article describes the synthesis of new biobased organocatalytic surfactants soluble in water, composed of a hydrocarbon chain grafted onto an imidazolidinone moiety. The imidazolidinone moiety acts as catalyst, but also as the polar head of the surfactant, while the fatty chain constitutes the hydrophobic tail. The five steps of the synthesis were optimized, respecting the principles of green chemistry, and two organocatalytic surfactants were obtained with a good selectivity. Surface properties in an aqueous medium were then evaluated with the use of tensiometric analysis. Their molecular organization in vesicles was characterized by Dynamic Light Scattering. The presence of vesicles allows reactions to be carried out in an organized aqueous medium. Model catalytic reactions performed in aqueous medium validated the feasibility of replacing conventional hazardous organic solvents. The newly synthesized biobased surfactants showed satisfactory catalytic activity and allowed the expected products to be obtained with good enantioselectivity. [ABSTRACT FROM AUTHOR]

[Display omitted] The monoalkyl diamine surfactant, N -dodecylpropane-1,3-diamine (DPDA), is expected to exhibit a pH-dependent charge switchability. In response to pH changes, the interfacial self-assembly of DPDA becomes an intermediary constituent that can potentially modify the interfacial interactions and structural assembly of both the oil and water phases. Hence, we hypothesize that as we change the pH, DPDA will respond to it by changing its charge and alkyl tail conformation as well as the conformation of adjacent phases at the molecular level, consequently affecting emulsion formation and stability. A neutral pH, resulting in a mono-cationic dialkyl amine, affects the conformation, driving an ordered self-assembly and stable emulsion. The pH-sensitivity and interfacial activity of DPDA were evaluated through pH titration and interfacial tension measurements. Subsequently, a molecular-level study of DPDA, as a pH-sensitive switchable surfactant, was performed at the dodecane-water interface using SFG spectroscopy. The interpretation of the vibrational spectra was further reinforced by determining the gauche defects in the interfacial alkyl chain organization and the extent of hydrogen (H) bonding between the interfacial water molecules. By adjusting the pH of water, the charge of the adsorbed DPDA molecules, their self-assembly, the organization of interfacial molecules, and ultimately the stability of the emulsion were tuned. At pH 7.0, the SFG spectra of DPDA showed that the interfacial alkyl chains were relatively well-ordered, while water molecules also had stronger H-bonding interactions. As a result, the oil–water emulsion showed improved stability. When water was at a high pH, the water molecules had fewer H-bonding interactions and relatively disordered alkyl chains at the interface, providing desirable conditions for demulsification. These observations were compatible with the observation in bulk emulsion preparation, confirming that alkyl chain packing and water H-bonding interactions at the interface contribute to overall emulsion stability. [ABSTRACT FROM AUTHOR]

Porous anorthite ceramics, as emerging green materials, garner significant interest in applications such as catalyst carriers, thermal insulation, and sound absorption due to their distinctive structural and functional attributes. In the present study, porous ceramics with anorthite as the main phase were prepared using the natural minerals kaolin, calcite, and quartz as raw materials, combined with a simple and environmentally friendly foam gel-casting method. By adjusting the additive content, we optimized the viscosity and stability of the slurry, and further investigated the impact of the slurry's foaming capacity on the resulting porosity, pore size, mechanical strength, and other key properties of the ceramics. Notably, the porous anorthite ceramic with 15 g/L of foaming agent demonstrated a porosity of 70.57 %, a bulk density of 0.81 g/cm3, and a thermal conductivity of 0.26 W/(mK), along with a commendable compressive strength of 8.85 MPa due to the homogeneous sub-spherical pore structure and plate-like anorthite grains. The suitability of these porous ceramics for catalyst carrier applications was confirmed through the effective photodegradation of a methyl orange solution. [ABSTRACT FROM AUTHOR]

Malassezia furfur is the primary etiological agent of dandruff (Pityriasis capitis). Although herbal shampoos are preferred for their natural, mild ingredients over synthetic counterparts, they are often perceived as less effective in managing flaky scalp conditions or furfuration causing dandruff. The study compares the antifungal efficacy of herbal and synthetic shampoos against M. furfur. Seven shampoos including herbal (HS_Adv, HS_M&P, HS_Aloe), synthetic (SYN_01, SYN_02, SYN_03) and an antifungal shampoo containing ketoconazole (KETO) were employed in the study. Experiments were designed to stimulate real-world conditions, utilizing disc-diffusion assay, 3-minute shampoo contact at mild dilutions (1% and 5%), recurrent 3-minute shampoo contact every 24 h with intermittent recovery. Both disc diffusion and 3-minute shampoo contact demonstrated that all shampoos were effectively inhibiting the viability of M. furfur. However, a single 3-minute shampoo contact followed by a prolonged recovery of 72 h revealed SYN_01 and KETO with maximal antifungal action. In contrast, herbal shampoos were as effective as synthetic options when M. furfur was subjected to 3-minute shampoo contact every 24 h with intermittent recovery. Comprehensive ingredient analysis revealed the robust antifungal activity in SYN_01 was probably because of the presence of various surfactants, allergens and a potent synthetic antifungal agent, Piroctone olamine. This study experimentally demonstrates that herbal shampoos are as effective as synthetic options in managing M. furfur-induced dandruff when applied consistently. The findings highlight the importance of regular scalp cleansing for dandruff management and provide valuable insights into the antifungal potential of both herbal and synthetic formulations. [ABSTRACT FROM AUTHOR]

There is little information on how widespread surfactants affect the adsorption of norfloxacin (NOR) onto iron oxide minerals. In order to elucidate the effects of various surfactants on the adsorption characteristics of NOR onto typical iron oxides, we have explored the different influences of sodium dodecylbenzene sulfonate (SDBS), an anionic surfactant, and didodecyldimethylammonium bromide (DDAB), a cationic surfactant, on the interactions between NOR and ferrihydrite under different solution chemistry conditions. Interestingly, SDBS facilitated NOR adsorption, whereas DDAB inhibited NOR adsorption. The adsorption-enhancement effect of SDBS was ascribed to the enhanced electrostatic attraction, the interactions between the adsorbed SDBS on ferrihydrite surfaces and NOR molecules, and the bridging effect of SDBS between NOR and iron oxide. In comparison, the adsorption-inhibition effect of DDAB owning to the adsorption site competitive adsorption between NOR and DDAB for the effective sites as well as the steric hindrance between NOR-DDAB complexes and the adsorbed DDAB on ferrihydrite surfaces. Additionally, the magnitude of the effects of surfactants on NOR adsorption declined with increasing pH values from 5.0 to 9.0, which was related to the amounts of surfactant binding to ferrihydrite surfaces. Moreover, when the background electrolyte was Ca2+, the enhanced effect of SDBS on NOR adsorption was caused by the formation of NOR-Ca2+-SDBS complexes. The inhibitory effect of DDAB was due to the DDAB coating on ferrihydrite, which undermined the cation-bridging effect. Together, the findings from this work emphasize the essential roles of widely existing surfactants in controlling the environmental fate of quinolone antibiotics. [ABSTRACT FROM AUTHOR]

Currently, the world faces serious challenges in meeting the growing demand for clean water. The present paper demonstrates the possibility of using the ultrafiltration (UF) process to reuse water from wastewater generated in car washes. Car washes commonly use foaming agents with dyes, which, although they are not necessary for washing cars, may hinder water reuse. For this reason, the aim of this work was to investigate the effect of the dyes present in car wash wastewater on the membrane fouling intensity. For this purpose, experimental tests were conducted with the application of a pilot plant with an industrial PCI B1 membrane module. The module was equipped with tubular FP100 (100 kDa) polyvinylidene fluoride (PVDF) membranes. For the feed, two types of cleaning agents and synthetic wastewater were used. The results obtained in the current study demonstrated that the UF membranes allowed the obtainment of the permeate characterized by high quality. In addition, it has been shown that the presence of Indigo carmine dye in the wastewater led to an increase in the fouling intensity. To sum up, it should be pointed out that the findings presented in the current study may be of key importance in the design of pilot installations used for the treatment of car wash wastewater. [ABSTRACT FROM AUTHOR]

Surfactants and polymers are widely used as shape-directing agents in the synthesis of colloidal plasmonic nanostars, consequently acting as non-negligible players in all those high-performance applications in which processes occur at their interfaces, such as surface enhanced Raman spectroscopy (SERS) and plasmon-induced catalysis. Therefore, elucidating surfactant- and polymer-metal interactions is critical to rationally improving the performance of nanostars in the same range of applications. In this mini-review, we present traditional and state-of-the-art characterization methods that can be used to investigate the ligand-surface interactions that occur on mature nanostars. Due to historically based limitations in the availability of nanostar-specific literature, we utilize nanorod literature as a starting point to critically infer which analytical approaches can be seamlessly translated to nanostar systems, and which instead need to be adapted to intercept the peculiar needs imposed by the branched nanoparticle morphology. [ABSTRACT FROM AUTHOR]

Cephalosporin C (CPC) is a critical raw material for cephalosporin antibiotics produced by Acremonium chrysogenum. During fermentation, the oxygen supply is a crucial factor limiting the efficient biosynthesis of CPC. This study demonstrated that the addition of exogenous surfactants significantly increased the dissolved oxygen (DO) level, extracellular catalase content, and final CPC titer. Consequently, we hypothesized and examined a correlation between catalase and CPC biosynthesis in A. chrysogenum through both the exogenous addition of hydrogen peroxide (H₂O₂) and the endogenous modulation of the catA expression level. The results indicated that both the addition of H₂O₂ and the ∆catA mutation exhibited similar fermentation trends, leading to decreased extracellular catalase activity and increased intracellular reactive oxygen species (ROS) content, which resulted in reduced CPC production. Conversely, strains that overexpress varying levels of the catA accelerated hyphal differentiation under DO-limiting conditions, reducing intracellular ROS accumulation and decreasing cellular apoptosis, which stabilized CPC yield during the later stages of fermentation. This study provides a critical foundation for further investigations into the regulatory mechanisms governing CPC biosynthesis in A. chrysogenum. [ABSTRACT FROM AUTHOR]

Bead-foaming technology effectively addresses production cycles, polymerization control, and cellular structure defects in conventional bulk foaming, especially in high-performance PMI foams. In this work, highly expandable PMI beads were synthesized based on the aqueous suspension polymerization of methacrylic acid-methacrylonitrile-tert-butyl methacrylate (MAA-MAN-tBMA) copolymers. The suspension polymerization was stabilized by reducing the solubility of MAA by the salting-out effect and replacing formamide (a common PMI foaming agent) with tBMA. The polymerization process was optimized by varying salting-out agents, dispersants, water-to-oil ratio (WOR), and stirring speed to achieve uniform bead sizes (0.2–0.4 mm) and high bead yields (>70%). The expansion ratio of the beads can be easily tuned by adjusting tBMA content and foaming time and temperature. Beads with 10%tBMA can reach up to 64 times under a free-forming process at 240 °C, which serves as an excellent precursor toward high-performance in-mold foaming PMI. The beads exhibit excellent in-mold foaming capabilities, thermal stability (Td = 392 °C), and mechanical properties. This work provides a technical foundation for the bead-foaming technology of PMI foams, reducing the cost of PMI foam production and providing the possibility to expand the application of PMI foam in civilian use. [ABSTRACT FROM AUTHOR]

Conventional PP with a linear chain structure is not suitable for foam processing due to its poor rheological properties. In this study, PP was modified with PE through reactive melt blending of maleic anhydride-grafted PP (MA-PP) with a small amount of PE bearing glycidyl groups on its backbone (G-PE), with the aim of enhancing the melt rheological properties of PP to make it suitable for foam processing. An anhydride–epoxy reaction occurred between MA-PP and G-PE during the melt processing, resulting in the formation of a crosslinked polymer network, which was confirmed by FTIR spectroscopy, a solubility test, and the presence of a rubbery plateau above the melting point. Melt rheological tests demonstrated that the modified PP showed a pronounced shear-thinning effect and higher elasticity compared to pristine PP. Foaming tests using supercritical carbon dioxide as a foaming agent in an autoclave demonstrated that the modified PP could produce a microcellular foam with a closed-cell structure, which was not achievable with neat PP. [ABSTRACT FROM AUTHOR]

Introduction: The European guideline for treatment of respiratory distress syndrome recommends less invasive surfactant administration (LISA) as the preferred method of surfactant administration in spontaneously breathing preterm infants. However, there is limited evidence on practical aspects such as sedation and catheter types, leading to considerable variability between centers. Methods: An anonymous online survey (www.soscisurvey.de) was sent to 164 tertiary neonatal intensive care units (NICUs) in Germany including 43 questions on practical aspects of LISA. Results: Of 122 (74%) participating NICUs, 117 (96%) reported experience with LISA with 82% of those reporting LISA as their preferred method of surfactant administration. Indications for surfactant administration differed widely between NICUs. Most (89%) used FiO2-thresholds only or in combination with other criteria, such as Silverman score/signs of dyspnea (41%) or lung ultrasound findings (3%). Prophylactic surfactant was administered by 42%. Differences in use of LISA in extremely immature infants were reported (e.g., 36% did not perform LISA in infants below 24–26 weeks). Preferred drugs for sedation were (Es-)Ketamine, followed by Propofol and Midazolam. Minimum time interval between subsequent LISA procedures was 4 (2–6) h. Catheters specifically designed for LISA were used by most NICUs (69%). Conclusion: This survey shows that LISA is common practice in German NICUs, but with considerable variability in practical aspects. These data may serve as a guidance for NICUs that have not yet implemented LISA and might be helpful design clinical trials with the aim to standardize and/or optimize LISA. [ABSTRACT FROM AUTHOR]

A comprehensive review of recent research on niosomes was conducted using a mixed methodology, including searches in databases such as Scopus, PubMed, and Web of Science (WoS). Articles were selected based on relevance. The current review examines the historical development of niosomes focusing on the methods of preparations and the contemporary strategies and prospective advancements within the realm of drug delivery systems, highlighting innovative approaches across transdermal, oral, and cellular delivery. This review reported the method of niosomes preparations including a new and novel approach for the preparation of niosomes known as the ball milling method (BM). This technique allows for the precise manipulation of size and shape, leading to improvements in drug release, encapsulation efficiency, and uniformity compared to traditional methods. Niosomes can serve as carriers for delivering various types of drugs, including hydrophobic, hydrophilic, and amphiphilic. This improves the efficiency of encapsulating different drugs, the size of targeted particles, and the desired zeta potential. This is achieved by using a specific charge-inducing agent for drug delivery and targeting specific diseases. These efforts are crucial for overcoming the current limitations and unlocking the full therapeutic potential of modern medicine. [ABSTRACT FROM AUTHOR]

Gas channeling treatment is a huge challenge for oil displacement and CO2 sequestration in the practical CO2 flooding process. The foaming agents can be used in the gas flooding process, which presents good application potential for gas channeling blockage. However, high temperature can affect surfactant foaming properties. This work takes a high-temperature heterogenous sandstone oil reservoir as an example; the foaming performance of different surfactants was evaluated via foamability, thermal stability, crude oil tolerance ability, and dynamic blocking capacity. The profile control performance of the optimized foaming agent was investigated via dual-core gas flooding experiments. (1) The results show that QPJ-c featured good foaming stability, which made it present the largest foam comprehensive index, although its foaming volume was slightly lower than that of QPJ-b. Its foaming volume retention rate was 83.2%, and its half-life retention rate remained 88.9% after 30 days aging at a temperature of 110 °C. (2) The foam resistance factor increased from 7 to 17 when the core permeability increased from 2 mD to 20 mD. This indicated that the high-permeability zone could be preferentially blocked by foam during the foam injection. (3) The dual-core flooding experiments verified that the fractional flow of the high-permeability core severely decreased due to the blockage of foam. The incremental oil recovery of the low-permeability core was 27.1% when the permeability ratio was 5. It increased to 40% when the permeability ratio was increased to 10. (4) Our work indicates that temperature-resistant CO2 foam could be a good candidate for profile control during CO2 flooding in the target reservoir. [ABSTRACT FROM AUTHOR]

[Display omitted] Lysopalmitoylphosphatidylcholine (LysoPC) is a soluble single-chain surfactant product of the innate immune system degradation of double-chain phospholipids. LysoPC adsorption to the air–water interface in lung alveoli can be modeled using alveolar-sized bubbles of constant surface area in a capillary pressure microtensiometer to show that adsorption is diffusion limited both below and above the critical micelle concentration (CMC). Above the CMC, a local equilibrium model is proposed in which depletion of the local monomer concentration drives dissociation of micelles in a region near the bubble surface. A capillary pressure microtensiometer in which a feedback loop maintains a constant bubble radius and surface area is used to measure dynamic surface tension during LysoPC adsorption. Direct numerical solution of the spherical diffusion equations, a new three parameter virial equation of state for interface thermodynamics, and a local equilibrium model of micellization above the CMC are used to accurately model the dynamic surface tension experiments both below and above the LysoPC CMC. LysoPC adsorption is shown to be diffusion-limited over concentrations ranging from below to well above the CMC, and to be well described by a local equilibrium model at concentrations above the CMC. Modelling the dynamic surface tension provides a reliable estimate of the micelle diffusivity near the CMC that is difficult to obtain by other methods in systems with low CMCs. [ABSTRACT FROM AUTHOR]

High‐strength foamed ceramics were synthesized employing silicon‐manganese slag (SM) and fluorgypsum (FG) as raw materials, with SiC serving as the foaming agent. Investigations into the influence of firing temperature and FG content on the phase structure, microstructure, and physical properties of foam ceramics were conducted. Characterization of the samples was performed through X‐ray diffraction and scanning electron microscopy. Results indicate that an increase in FG content lowers the matrix melting point, promotes crystal growth, enhances compressive strength, and forms a uniform pore structure. At an FG content of 11%, ceramics prepared at a firing temperature of 1130°C exhibit a density of 0.56 g/cm3, porosity of 78.45%, and compressive strength of 3.05 MPa. This study explores the use of FG as a cost‐effective alternative to borax, demonstrating a sustainable approach for foam ceramics preparation using silicomanganese slag and FG synergy. [ABSTRACT FROM AUTHOR]

The production of foamed ceramics from recycled solid waste using the innovative and eco-friendly gel casting method represented a significant advancement in materials synthesis. The foamed ceramics for architectural decoration (PTFCs) were prepared through the foaming gel casting process by using phosphorus tailings as raw material with the addition of sodium dodecyl sulfate (SDS) as a foaming agent. The rheology and gelation of the slurry were examined, and the properties of PTFCs were determined at different foaming agent concentrations, solid loadings, and heat treatment temperatures. The growth and proliferation of micelles enhanced the foaming ability of the slurry, leading to a significant reduction in the bulk density of PTFCs from 1.17 g/cm3 to 0.47 g/cm3 by adjusting the concentration of SDS (0 wt% - 1.5 wt%). PTFCs containing 70 wt% phosphorus tailings demonstrated superior pore structure and mechanical properties compared to specimens with low solids loading. The strength of PTFCs was enhanced by optimizing the heat treatment temperature (875 °C – 975 °C). The introduction of air into the slurry through high-speed stirring, the foaming action of SDS, and the formation of numerous pores during the synthesis of PTFCs due to the high-temperature decomposition of phosphorus tailings, collectively contributed to a significant improvement in the comprehensive performance of PTFCs. The bulk density, porosity, and compressive strength of PTFCs synthesized by adding phosphorus tailings powder (with a content of 70 wt%) and SDS (with a concentration of 0.6 wt%) and heat treatment at 925 °C were determined to be 0.71 g/cm3, 77.58 %, and 4.73 MPa. This innovative technology enabled the large-scale recycling of phosphorus tailings into the development of lightweight and eco-friendly porous building materials. [ABSTRACT FROM AUTHOR]

In recent years, mortar bricks or autoclaved aerated concrete (AAC), also known as foamed concrete, have been widely used as masonry wall materials. Foamed concrete, like bricks, can be produced by adding a foaming agent to achieve the desired weight and density, while meeting requirements for strength and durability. However, the search for sustainable construction materials has become imperative, including the use of waste materials to partially replace cement. The incorporation of SCM in the production of cement-based materials, such as foamed concrete, has a significant impact on reducing CO2 emissions and promoting a sustainable environment. POFA, a secondary product derived from the palm oil industry that is typically left on the ground, poses environmental problems. Due to its good performance and pozzolanic reactions, POFA-based construction materials have great potential as alternatives to ordinary Portland cement. Unlike previous studies, this research evaluates the strength and durability of foamed concrete with variations in foam agent dosages, including finer particles of POFA (100µm) as a partial cement replacement. The study produced a total of 6 batches of foamed concrete, measuring compressive strength, porosity, water absorption, and electrical resistivity. Additionally, the research examined the correlation between compressive strength and porosity, as well as compressive strength and electrical resistivity. This study concludes that an ideal content of 10% POFA with a foaming agent-to-water ratio (fa/w) of 1/60 can achieve the best strength of foamed concrete. Furthermore, a partial cement replacement with 20% POFA could potentially increase the compressive strength to levels similar to those of normal foamed concrete (without POFA). [ABSTRACT FROM AUTHOR]

Rice husk is a typical solid waste generated during rice processing, typically disposed of by combustion or landfills. One promising method for repurposing rice husk ash is as a pozzolan in geopolymer foam. This study explores additives like hydrogen peroxide and sodium alcohol ether sulfate (SAES) to enhance the properties of porous geopolymer foam made from rice husk ash. Hydrogen peroxide is utilized as a foaming agent to enhance porosity, while SAES acts as a stabilizer to influence the structure of the foam. The foam was prepared by mixing sodium silicate, sodium hydroxide, rice husk ash, genioperl, hydrogen peroxide, and stabilizer in specific ratios. Two variables are hydrogen peroxide (0.0, 0.1, 0.2, 0.3, and 0.4 wt.%) and SAES (0.0, 0.5, 1.0, 1.5, and 2.0 wt.%). The compressive strength and total porosity tests are conducted according to standards. The results show that increased hydrogen peroxide increased total porosity but decreased compressive strength. On the other hand, SAES improved the foam's structural integrity and maintained the compressive strength without significantly increasing porosity at 1.0 wt.% concentrations. The optimal total porosity and compressive strength were achieved with 0.40 wt.% hydrogen peroxide and 1.0 wt.% SAES. This study contributes to agriculture science and technology by exploring the potential use of rice husk ash-based geopolymer foam and determining the optimum formulation for its production. The findings also suggest that this foam can be utilized in various agricultural applications such as buildings, pipelines, and agriculture fields. [ABSTRACT FROM AUTHOR]

Due to the significant amount of solid waste generated annually in China, the rational use of these wastes has become increasingly important. The production of foam ceramics is considered an effective method for the large-scale utilization of such solid waste. In this study, granite sawing mud was selected as the raw material, with SiC and MnO2 serving as foaming agent to prepare foam ceramics. The foaming behavior of sintered samples using different foaming agent was investigated to determine the most suitable type and amount of foaming agent for obtaining foam ceramics with excellent pore structures. Additionally, the effects of the foaming agent on the pore structure and physical mechanical properties of the foam ceramics were studied in detail. The results showed that SiC and MnO2 both resulted in the pronounced expansion to different extent, and increasing the content of foaming agent enhances foam expansion. The best dosage of SiC was 1%, the optimum additive amount of MnO2 is 2–3%. For SiC, the oxidation reduction reaction occurred between SiC and O2 to generate CO2/CO. For MnO2, firstly, the reduction of MnO2 to Mn2O3 occurred, and then the Mn2O3 dissolved in the glass melt and, subsequently, Mn3+ was reduced to Mn2+, leading to gas formation and foaming. Under the same dosage of foaming agent and preparation conditions, the sample prepared with SiC as the blowing agent has higher compressive strength, lower water absorption, and a more uniform pore structure. [ABSTRACT FROM AUTHOR]

Nitrogen foam is a promising enhanced oil recovery (EOR) technique with significant potential for tertiary oil recovery. This improves the efficiency of the oil displacement during the gas drive processes while expanding the swept volume. However, in the high-temperature, high-salinity reservoirs of the Tahe Oilfield, conventional N2 foam systems show suboptimal performance, as their effectiveness is heavily limited by temperature and salinity. Consequently, enhancing the foam stability under these harsh conditions is crucial for unlocking new opportunities for the development of Tahe fracture-vuggy reservoirs. In this study, the Waring–Blender method was used to prepare weathered coal particles as a foam stabilizer. Compared to conventional foam stabilizers, weathered coal particles were found to enhance the stability of the liquid film under high-temperature and high-salinity conditions. Firstly, the foaming properties of the six foaming agents were comprehensively evaluated and their foaming properties were observed at different concentrations. YL-3J with a mass concentration of 0.7% was selected. The foaming stabilization performance of four types of solid particles was evaluated and weathered coal solid particles with a mass concentration of 15% and particle size of 300 mesh were selected. Therefore, the particle-reinforced foam system was determined to consist of "foaming agent YL-3J (0.7%) + weathered coal (15.0%) + nitrogen". This system exhibited a foaming volume of 310 mL at 150 °C and salinity of 210,000 mg/L, with a half-life of 1920 s. Finally, through interfacial tension and viscoelastic modulus tests, the synergistic mechanism between weathered coal particles and surfactants was demonstrated. The incorporation of weathered coal particles reduced the interfacial tension of the system. The formation of a skeleton at the foam interface increased the apparent viscosity and viscoelastic modulus, reduced the liquid drainage rate from the foam, and mitigated the disproportionation effect. These effects enhanced the temperature, salinity resistance, and stability of the foam. Consequently, they contributed to the stable flow of foam under high-temperature and high-salinity conditions in the reservoir, thereby improving the oil displacement efficiency of the system. [ABSTRACT FROM AUTHOR]

The fracture-cavity carbonate reservoir in Tahe oilfield is buried deep (more than 5000 m). The reservoir has low permeability, strong heterogeneity, large size, diverse forms of connectivity, and complex spatial distribution. In conventional water flooding, it is difficult to improve oil recovery effectively because of small water flood sweep and large injection pressure. Pressure flooding is a new water injection technique that can change the reservoir pore space. Combined with an oil displacement agent, pressure flooding is expected to improve the recovery rate of carbonate reservoirs. In this paper, the influence factors of pressure flooding technology are studied, and a set of surfactant systems suitable for high-temperature and high-salt reservoirs is developed. The results show that only an appropriate injection flow can produce microfractures. Only an appropriate displacement rate can optimize the effects of pressure flooding. With an increase in crude oil viscosity, the recovery rate after pressure flooding decreases gradually. A complex fracture network is formed in reservoirs after pressure flooding. The new surfactant system has good interfacial tension reduction properties and excellent stability. Pressure flooding experiments with the addition of a surfactant showed that the system can help to improve the recovery of pressure flooding. [ABSTRACT FROM AUTHOR]

In response to global energy, resource, and climate challenges, foamed concrete—a sustainable, low-carbon building material—offers advantages due to its lightweight nature and high thermal insulation. This study focused on alkali-activated foamed concrete (A07 grade, average density of 723 kg/m3) prepared from slag and fly ash under alkaline conditions. Using S95-grade slag powder and I-grade ground fine fly ash as raw materials, a sodium silicate and NaOH solution as the activator, and YS-200 composite cement foaming agent, alkali-activated foamed concrete with a density grade of A07 was prepared by physical foaming. The effects of water–binder ratio, fly ash content, and alkali equivalent on compressive strength, water absorption, drying shrinkage, and frost resistance were investigated. With a dry density of 300–1800 kg/m3 (1/10 to 1/3 of conventional concrete), it reduced building weight by 25–40%. [ABSTRACT FROM AUTHOR]

Interfacial properties significantly influence emulsifying and foaming stability. We here explore the interfacial behavior of egg yolk granules (EYGs) combined with various Span emulsifiers (Span 20, 40, 60, 80) to assess their solution properties, interface dynamics, and effects on emulsifying and foaming stability. The results unveiled that as the Span concentration increased, particle size decreased from 7028 to 1200 nm, absolute zeta potential increased from 4.86 to 9.26 mv, and the structure became increasingly loosened. This loose structure of EYGs-Span complexes resulted in reduced interfacial tension (γ), higher adsorption rate (Kd), and improved interfacial composite modulus (E) compared with native EYGs. These effects were more pronounced with shorter hydrophobic chain Spans but diminished with longer chain lengths. Enhanced interfacial properties contributed to better emulsification and foaming stability, with EYGs-Span complexes displaying increased emulsifying ability and stability compared with natural EYGs. Emulsifying and foaming stability improved in the order of Span 20 > Span 40 > Span 60 > Span 80 as the Span concentration increased. The correlation analysis (p > 0.05) indicated that emulsifying stability was positively associated with interfacial composite modulus and negatively correlated with particle size. Consequently, EYGs-Span composites demonstrate considerable potential for use as effective emulsifiers in food industry applications. [ABSTRACT FROM AUTHOR]

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Nowadays, the post-consumer polyethylene terephthalate (PET) waste from the packaging industry is one of the largest plastic waste streams worldwide. While clear PET waste is commonly recycled and is reused for textile and packaging applications (even with food contact), coloured PET waste's degraded state limits its reusing potential. This highlights the urgent need to upgrade low-value PET waste. This study focuses on enhancing coloured recycled PET (rPET) quality by introducing an epoxide chain extender (CE) from 0 to 1 wt%, to improve rheological behaviour. Simultaneously, upcycling opportunities are explored by incorporating an eco-friendly phosphorous-based flame retardant (FR) from 0 to 10 wt%, to reduce flammability and thus enabling electrical and electronic applications, among others. The impact of each additive, as well as their combination, is evaluated on the chemical structure, thermal, rheological and burning behaviour of undervalued rPET. The optimal CE content is determined at 0.8 wt%, promoting branched and higher molecular weight polymer chains. Regarding FR, 6, 8 and 10 wt% highly enhance the fire resistance. Furthermore, the combination CE/FR enables a synergistic effect, notably improving burning behaviour. Additionally, the foaming potential of the resulting high-value rPET is assessed for the first time through one-step batch foaming using supercritical CO2 as foaming agent, aiming to develop lightweight materials endowed with superior burning behaviour. The material containing 0.8 wt% CE reaches the lowest density (200 kg/m3) and a closed cellular structure with smaller cell diameters (8 ± 3 μm). Meanwhile, the combination of 0.8 wt% CE and 6 wt% FR gives rise to a foamed material with density of 659 kg/m3 and cell diameter of 7 μm. Thus, this batch procedure in one-step enables the formation of microcellular foams based on coloured rPET (cell size below 10 μm). [ABSTRACT FROM AUTHOR]

The use of cellulose fiber-filled polypropylene (PP) composites in combination with foam injection molding has enabled the lightweight design of injection-molded parts. The study provides achievements for the physical foam injection molding (MuCell®) process of PP–cellulose fiber compounds by using CO2 as the direct foaming agent, including a comparison of MuCell® foaming with N2 and a comparison to a chemical foaming process. Weight and density reductions, foam structure and specific mechanical properties are highly dependent on the applied processing parameters. The maximum weight reduction reached values of up to 16%, and density reduction even reached 33% in relation to the compact plates. The extent of weight and density reduction could be adjusted, among other factors, by a reduction in the shot volume. Setting the density reduction to 22% allowed for simultaneously decreasing weight while sustaining the specific flexural properties and limiting the loss of specific impact strength. By using optimized FIM parameters, the mechanical performance could be improved, with specific modulus values even outperforming the compact reference sample. This presents a significant benefit for the preparation of lightweight products and sets the basis for further optimization and modeling studies. [ABSTRACT FROM AUTHOR]