Search Results (2,701)

Pea albumin is a high-quality plant-based protein with growing relevance in food applications, yet the effects of pH and thermal treatment on its structural and functional properties remain insufficiently understood. This study investigated the effects of environmental factors, namely pH (3, 5, 7, 9) and temperature (40, 60, 80, 100 °C), on the structural behavior and functionality of pea albumin. Structural changes were characterized through particle size, Zeta potential, surface hydrophobicity, and intrinsic fluorescence. Functional properties, including solubility, foaming ability, and emulsifying capacity, were evaluated and compared with untreated controls. Under alkaline conditions (pH 9), stronger electrostatic repulsion led to a 29.5% reduction in particle size, a 76.47% increase in Zeta potential, enhanced protein unfolding, and a 19.06% increase in surface hydrophobicity. At this pH, solubility increased by 24.8%, accompanied by notable improvements in foaming and emulsifying performance. Moderate heating (40, 60 °C) induced partial unfolding, resulting in decreased particle size and enhanced solubility, which further contributed to improved functional behavior. Pearson correlation analysis demonstrated significant associations between structural indicators (particle size, Zeta potential, surface hydrophobicity) and functional properties, highlighting the structure–function relationship of pea albumin. This work provides a comprehensive understanding of environmental factor-induced changes in pea albumin and offers valuable insights for its optimized application in plant-based foods. Full article

Biomass liquefaction is a thermochemical process that converts lignocellulosic materials into reactive liquid intermediates, enabling the production of bio-based polyols as a sustainable alternative to petroleum-derived chemicals. This study investigates the liquefaction of two lignocellulosic biomasses, Red Angico (Anadenanthera colubrina) and Mahogany (Swietenia macrophylla), using a glycerol–ethylene glycol polyalcohol system, chosen for its renewable origin and high solvating efficiency. The resulting polyols were used to produce polyurethane (PU) foams, and their properties were evaluated in relation to biomass composition. The chemical composition of each biomass significantly influenced its liquefaction behavior and polyol characteristics. Mahogany achieved higher liquefaction efficiency, whereas Red Angico polyols generated PU foams with superior mechanical performance, highlighting the influence of species-specific chemistry. Water content and isocyanate index were found to modulate foam structure and compressive strength. This work demonstrates how tailored liquefaction strategies using polyalcohol systems can optimize bio-based PU foam properties, providing a sustainable route for high-performance polymer materials. Full article

This paper discusses the total replacement of egg white (EW) with faba bean protein concentrate (FPC) in a marshmallow formulation. The physico-chemical and techno-functional characterizations of the ingredients revealed that FPC, with a protein content of 68%, exhibited an interesting foaming capacity (200%) compared to EW, which had comparable foaming stability. The physico-chemical properties of the final products indicated that the FPC marshmallow (FPCM) had a higher density (0.519 g/mL), lower moisture (17.337%), and a water activity within the recommended range for this type of product. The FPCM had the highest hardness and elasticity values but the lowest cohesiveness and adhesiveness. Scanning electron microscopy showed that the FPCM structure is similar to that of the EW marshmallow (EWM). In front-face fluorescence spectroscopy measurements, the FPCM exhibited higher emission intensity for tryptophan with a maximum at 382 nm and vitamin A with a maximum located around 338 nm. FTIR analysis presented higher peaks at 850, 918, and 1034 cm⁻¹ for the EWM compared to the FPCM. In a hedonic evaluation, the majority of descriptors (hardness, odor, and general acceptability) showed similar scores for both formulations. All results demonstrated the success of the total substitution of egg white by FPC in the marshmallow formulation. Full article

The aim of this work is to develop structurally enhanced and highly hydrophobic polyurethane (PU) foams for the efficient remediation of liquid organic pollutants. For this purpose, PU foams were modified with renewable activated biochar derived from marine algae (AC) and a hydrophobic polydimethylsiloxane (PDMS) coating, producing four systems: pristine PU, PU-AC, PU/PDMS, and the hybrid PU-AC/PDMS composite. The study evaluates how AC incorporation and PDMS surface functionalization influence the microstructure, chemical composition, wettability, thermal stability, and sorption behavior of the foams. SEM images revealed progressive reductions in pore size from 420 ± 80 μm (PU) to 360 ± 85 μm (PU-AC/PDMS), with AC introducing heterogeneity while PDMS preserved open-cell morphology. FTIR confirmed the presence of urethane linkages, carbonaceous structures, and PDMS siloxane groups. Surface hydrophobicity increased markedly from 88.53° (PU) to 148.25° (PU-AC/PDMS). TGA results showed that PDMS improved thermal stability through silica-rich char formation, whereas AC slightly lowered degradation onset. Sorption tests using petroleum-derived oils and hydrophobic organic liquids demonstrated a consistent performance hierarchy (PU < PU/PDMS < PU-AC < PU-AC/PDMS). The ternary composite achieved the highest uptake capacities, reaching 44–56 g/g for oils and up to 35 g/g for hydrophobic solvents, while maintaining reusability. These findings demonstrate that combining activated biochar with PDMS significantly enhances the functional properties of PU foams, offering an efficient and sustainable material for oil–water separation and organic pollutant remediation. Full article

The flow around circular cylinders is a classic problem in fluid mechanics with significant implications for offshore engineering. While extensive numerical and experimental research has focused on the subcritical and critical Reynolds regimes, the supercritical and postcritical regimes remain challenging and relatively unexplored, primarily due to the complex nature of turbulence and the high computational requirements. In this study, we perform three-dimensional detached eddy simulations using the finite volume method in OpenFOAM v1906, employing Menter’s k-$\omega$ SST turbulence model, to systematically investigate the flow past an infinitely long smooth cylinder from the subcritical through the postcritical regimes. The numerical setup ensures accurate near-wall resolution and reliable representation of unsteady flow features. We present a detailed analysis of vortex shedding patterns, wake evolution, and statistical properties of lift and drag coefficients for selected Reynolds numbers representative of each regime. The simulation results are benchmarked against experimental data from the literature, demonstrating good agreement for Strouhal number and mean drag. Special emphasis is placed on the evolution of wake topology and force coefficients as the flow transitions from laminar to fully turbulent conditions. The findings contribute to the limited numerical literature on flow around circular cylinders across subcritical, critical, supercritical, and postcritical Reynolds number regimes, providing insights that are fundamentally relevant to the broader scope of understanding vortex shedding phenomena. Full article

The N Oilfield is the first offshore extra-heavy oilfield developed using thermal recovery methods, adopting cyclic steam stimulation (CSS) and commissioned in 2022. The development of offshore heavy oil reservoirs is confronted with numerous technical and operational challenges. Key constraints include limited platform space, stringent economic thresholds for single-well production, and elevated operational risks, collectively contributing to significant uncertainties in project viability. For effective exploitation of the target oilfield, a comprehensive strategy was proposed, which consisted of effective artificial lifting, steam channeling and high water cut treatment. First, to achieve efficient artificial lifting of the extra-heavy oil, an integrated injection–production lifting technology using jet pump was designed and implemented. In addition, during the first steam injection cycle, challenges such as inter-well steam channeling, high water cut, and an excessive water recovery ratio were encountered. Subsequent analysis indicated that low-quality reservoir intervals were the dominant sources of unwanted water production and preferential steam channeling pathways. To address these problems, a suite of efficiency-enhancing technologies was established, including regional steam injection for channeling suppression, classification-based water shutoff and control, and production regime optimization. Given the significant variations in geological conditions and production dynamics among different types of high-water-cut wells, a single plugging agent system proved inadequate for their diverse requirements. Therefore, customized water control countermeasures were formulated for specific well types, and a suite of plugging agent systems with tailored properties was subsequently developed, including high-temperature-resistant N₂ foam, high-temperature-degradable gel, and high-strength ultra-fine cement systems. To date, regional steam injection has been implemented in 10 well groups, water control measures have been applied to 12 wells, and production regimes optimization has been implemented in 5 wells. Up to the current production round, no steam channeling has been observed in the well groups after thermal treatment. Compared with the pre-measurement stage, the average water cut per well decreased by 10%. During the three-year production cycle, the average daily oil production per well increased by 10%, the cumulative oil increment of the oilfield reached 15,000 tons, and the total crude oil production exceeded 800,000 tons. This study provides practical technical insights for the large-scale and efficient development of extra-heavy oil reservoirs in the Bohai Oilfield and offers a valuable reference for similar reservoirs worldwide. Full article

The recycling of ultralight foam concrete (ULFC), both with and without phase-change material (PCM), involves crushing it and using the resulting recycled foam concrete powder (RFCP) as a partial substitute for cement or sand in cement composites. These recycling paths remain insufficiently explored in the literature regarding practical feasibility. Since both RFCP and PCM reduce the flowability of fresh mortars, incorporating RFCP with PCM is, in practice, only feasible with the addition of a superplasticizer (SP). The primary objectives of this study were to determine: (1) the effect of RFCP with PCM, when used to replace cement or sand, on mortar properties, and (2) its influence on the performance of the superplasticizer (SP), to assess the feasibility of using RFCP with PCM in cement composites. The addition of RFCP, both without PCM (RFCP_0) and with PCM (RFCP_PCM), deteriorates the properties of fresh and hardened mortars compared to reference mortars. The negative impact of RFCP is less pronounced when it replaces sand rather than cement. Compared to RFCP_0 mortars, RFCP_PCM mortars exhibit reduced flowability. PCM delays setting and reduces heat evolution during the first 48 h of hardening. PCM does not significantly affect strength or water absorption but increases shrinkage and lowers thermal conductivity. While RFCP_PCM does not impair SP efficiency, PCM causes SP to significantly retard setting and hardening. Full article

Aluminum foam is attracting attention as a multifunctional, ultra-lightweight material. To apply this aluminum foam to actual industrial materials, aluminum foam plates are required. In addition, it is expected that a multi-layer aluminum foam composed of dissimilar aluminum alloy foam layers can further enhance its functionality. In this study, we attempted to fabricate a three-layer aluminum foam composed of commercially pure aluminum AA1050 and Al-Mg-Si aluminum alloy AA6061 by heating and foaming a total of three pieces of AA1050 precursor and AA6061 precursor arranged alternately, followed by immediate roller joining. It was found that, by traversing a roller immediately after foaming the AA1050 and AA6061 precursors, the aluminum foam could be joined while forming it into a flat plate. In addition, X-ray CT images of the fabricated samples revealed that material flow induced by roller traversing ruptured the surface skin layer. Numerous pores were observed within the sample, indicating pores were maintained during the roller traversing and no significant differences in porosities were identified between AA1050 aluminum foam and AA6061 aluminum foam. Furthermore, from the four-point bending test and the observation of samples after bending test, although quantitative mechanical properties were not obtained due to the as-joined samples were used for the bending test, pores were observed at the fracture surfaces, confirming that roller joining achieved seamless joining. Full article

The invasive fish Atherina boyeri constitutes an ecologically disruptive yet underexploited biomass with strong potential for transformation into value-added biofunctional ingredients. This study investigates the functional, antioxidant, and antimicrobial properties of protein hydrolysates that were produced from fish collected in the Hirfanlı and Yamula reservoirs using three commercial proteases (alcalase, bromelain, and flavourzyme). Bromelain produced the highest degree of hydrolysis, yielding higher proportions of low-molecular-weight peptides and greater radical-scavenging activity. Flavourzyme hydrolysates exhibited the most favorable emulsifying properties, Alcalase hydrolysates produced the highest foaming capacity and stability. All hydrolysates showed high absolute zeta-potential values across pH 3–9, demonstrating strong colloidal stability. Protein solubility remained above 80% across most pH levels, indicating extensive peptide release and improved compatibility with aqueous media. The Oil-binding capacity (2.78–3.75 mL/g) was consistent with reported values for marine hydrolysates. Antioxidant and antimicrobial evaluations revealed clear enzyme-dependent patterns, with Bromelain exhibiting the strongest DPPH activity and Alcalase and Flavourzyme showing the most pronounced inhibition of major foodborne pathogens. Additionally, all hydrolysates exhibited measurable ACE-inhibitory activity, with flavourzyme-derived peptides showing the highest inhibitory activity, underscoring their potential relevance for antihypertensive applications. These findings highlight the strategic valorization of A. boyeri through enzymatic hydrolysis, demonstrating its potential as a sustainable, clean-label functional ingredient source. Full article

Grape polysaccharide extracts derived from winemaking by-products have been shown to affect key wine characteristics. This study aimed to investigate the application of different grape-derived, polysaccharide-rich extracts and commercial yeast products in white sparkling wines, since no other studies have been found. The impacts of these products on the volatile, phenolic and polysaccharide compositions, as well as on the foam properties and sensory characteristics, were evaluated. After 15 months of aging, the products used did not influence the color and phenolic composition of the sparkling wines. However, they had a positive effect on the volatile compounds, with treated wines showing a general increase compared with the control, mainly in ethyl esters and alcohol acetates, compounds associated with fruity and floral notes. The treated wines showed clear sensory differences compared with the control, including aromatic complexity, which may reflect better preservation of certain aromatic compounds over time. In addition, improvements in wine taste were observed, likely due to a reduction in perceived acidity and bitterness. These results demonstrate the potential of grape-derived polysaccharide extracts to preserve volatile compounds in sparkling wines and to enhance their aromatic complexity and mouthfeel, thus improving overall sensory quality. Full article

This study reports on the use of degraded lignin in combination with tannins to develop sustainable, formaldehyde-free, and bio-based phenolic foams. Mechanical, thermal, and flame-retardant properties of the different foams were systematically evaluated using compression testing, thermogravimetric analysis (TGA), mass loss cone calorimetry (MLC), and UL-94 flammability tests. Lignin degradation/activation was carried out via a hydrothermal process in the presence of ethanol. Ethanol-induced lignin hydrogenolysis and thermal degradation were deemed a necessary step to obtain foams with satisfactory mechanical, morphological, and thermal insulation properties. Meanwhile, the fire resistance assessed by MLC remains comparable to that of tannin-based foams, with a similarly low peak heat release rate (pHRR). Full article

Surfactants are commonly employed in cleaning, cosmetic, and pharmaceutical formulations due to their ability to lower surface tension and facilitate the formation of emulsions, foams, and dispersions. Recent research highlights the advantages of synergistic interactions between anionic and nonionic surfactants to improve overall performance. In this study, the physicochemical properties and performance of binary mixtures of the anionic surfactant sodium lauryl sulfate (SLS) and the amphoteric surfactant lauryl dimethyl amine oxide (LDAO) at varying ratios (100% SLS, 90:10, 80:20, 70:30, 60:40, and 50:50) were investigated. Key parameters analysed included critical micelle concentration (CMC), surface tension (γ), foam volume, and potential irritability, assessed via the Zein test. The results revealed a clear synergistic effect between SLS and LDAO: all mixtures showed reduced CMC and minimum surface tension compared to the individual surfactants, while exhibiting enhanced foam volume and stability. Regarding irritability, increasing LDAO content consistently led to decreased protein denaturation, indicating lower irritancy levels. Furthermore, the results obtained in the Zein test confirmed that mixtures induced less protein denaturation than the sum of their individual surfactant components, with formulations ranging from moderately to non-irritating. The results obtained indicate that the more stable mixed micelle systems (SLS + LDAO) might improve the performance of cleaning formulations (γ, CMC, foam) while reducing the irritability. Full article

Shape-memory polymers (SMPs) are a class of smart materials capable of recovering their original shape from a programmed temporary shape in response to external stimuli such as heat, light, or magnetic fields. SMPs have attracted significant interest for biomedical devices and soft robotics due to their large recoverable strains, programmable mechanical and thermal properties, tunable activation temperatures, responsiveness to various stimuli, low density, and ease of processing via additive manufacturing techniques, as well as demonstrated biocompatibility and potential bioresorbability. This review summarises recent progress in the fundamentals, classification, activation mechanisms, and fabrication strategies of SMPs, focusing particularly on design principles that influence performance relevant to specific applications. Both thermally and non-thermally activated SMP systems are discussed, alongside methods for controlling activation temperatures, including plasticisation, copolymerisation, and modulation of cross-linking density. The use of functional nanofillers to enhance thermal and electrical conductivity, mechanical strength, and actuation efficiency is also considered. Current manufacturing techniques are critically evaluated in terms of resolution, material compatibility, scalability, and integration potential. Biodegradable SMPs are highlighted, with discussion of degradation behaviour, biocompatibility, and demonstrations in devices such as haemostatic foams, embolic implants, and bone scaffolds. However, despite their promising potential, the widespread application of SMPs faces several challenges, including non-uniform activation, the need to balance mechanical strength with shape recovery, and limited standardisation. Addressing these issues is critical for advancing SMPs from laboratory research to clinical and industrial applications. Full article

Running shoe midsoles are designed to attenuate impact forces while maintaining or improving performance. However, the literature is equivocal, likely due to measurement systems, whereas in vitro testing is conclusively favourable. This study investigated three densities of ATPU foam, comparing in vitro mechanical properties with in vivo plantar force spectral characteristics derived from individualised pressure distributions during treadmill running at varied speeds. In vitro results of slab foam and shoes showed strong positive relationships between impact variables normalised to total impact energy and foam density (r² > 0.90), and strong negative relationships for time-domain variables normalised to deformation (mm) as density increased (r² > 0.89). During running, lower midsole density increased ground contact time across speeds (p = 0.041), while spatially resolved high-frequency PSD and peak impact force both decreased (p = 0.043; p = 0.030). However, there were no differences between total vertical force and midsole density (p = 0.232). Relationships between in vitro Peak G and high-frequency PSD were strong across all speeds (r² = 0.63–0.91). Conversely, reducing midsole density increased active peak force across speeds (p = 0.003), which was strongly related to in vitro energy return (r² > 0.89). Therefore, plantar force spectra and spatially resolved analyses demonstrate how foam density properties translate from in vitro to in vivo treadmill running, with lower-density foam improving impact attenuation but elevating propulsive forces. Future work needs to verify this in an outdoor setting. Full article

The “Double High—Double Extra High” stage of offshore oilfields, where large pumps lift liquids, leads to a rapid rise in water concentration, which triggers a decrease in rock strength and exacerbates the risk of sand production; this leads to a blockage of the reservoir, thus restricting the release of production capacity. In this paper, for the typical weak cementation strength of unconsolidated sandstone of a Class I reservoir in the P oilfield, numerical simulation and indoor experimental methods are utilized to explore the plugging mechanism and law of the water-contenting conditions, with micro-sand and mud conditions, on the screen. Considering the combined effects of reservoir particulate transport plugging and near-well sand control media plugging, the additional pressure drop and skin factor calculation model is constructed, and a dynamic capacity prediction model for sand control wells is formed. By matching the physical properties of the target reservoir and optimizing the sand control method, the production capacity prediction model and the sand control optimization design method for the high water-content period of the unconsolidated sandstone reservoir are finally obtained. The results show that the median sand size of well A1 in the P oilfield Class I reservoir is 220 μm, the sand transportation diameter is about 15–20 m, the serious plugging area near the well is distributed in 2–2.5 m, and the predicted loss of production capacity is about 18%. The use of a foam metal screen can significantly reduce the plugging pressure and increase the flow of crude oil, which is 2.2 and 1.2 times higher than that of the precision mesh and pre-filled screen, respectively. These research results can provide technical support and theoretical guidance for the sustained, efficient, and stable production of sand reservoirs in the Bohai Oilfield. Full article