Search Results (634)

Cellulose-derived gel films are promising matrices for the immobilization and delivery of beneficial microorganisms in sustainable plant protection. This study evaluated the effects of polymer molecular weight and chemical structure on the physicochemical properties and biocontrol performance of hydroxyethyl cellulose (HEC) films of low, medium, and high molecular weight, as well as sodium carboxymethyl cellulose (CMC-Na), loaded with Bacillus subtilis. The films were characterized in terms of morphology, swelling behavior, mechanical properties, microbial viability, and antifungal activity against Fusarium avenaceum and Alternaria solani. Increasing HEC molecular weight produced progressively denser and more homogeneous gel networks, resulting in improved structural integrity, whereas CMC-Na formed dense but less stable networks. Swelling studies at pH 4, 7, and 9 showed high water uptake for all HEC systems, with enhanced structural stability observed in high-molecular-weight films, whereas CMC-Na dissolved rapidly under all conditions. Mechanical testing further confirmed that increasing molecular weight enhanced stiffness and tensile strength but reduced flexibility. Immobilized in gel matrices, B. subtilis remained viable after 12 months of storage and rapidly reactivated after rehydration. All biohybrid films inhibited fungal growth, with stronger formulation-dependent responses against F. avenaceum than against A. solani. In general, polymer molecular weight and structure were identified as key parameters controlling network organization, hydration behavior, mechanical performance, and biological functionality. These findings highlight the potential of cellulose-derived gel matrices as tunable carriers for microbial biocontrol applications. Full article

The global construction industry urgently requires sustainable alternatives to ordinary Portland cement (OPC) to mitigate its immense carbon footprint. Red mud (RM), a highly alkaline bauxite residue, presents tremendous but challenging potential as a supplementary cementitious material. This review systematically bridges the gap between atomic-level interfacial bonding mechanisms and macroscopic engineering performance, highlighting how these properties are significantly dictated by specific RM sources (e.g., Bayer vs. Sintering processes). We first elucidate advanced pretreatment strategies, notably CO₂ mineralization, which synergistically mitigates extreme alkalinity and sequesters carbon. Crucially, the fundamental bonding mechanisms are decoded: beyond physical filling, RM integration induces significant micro-morphological densification via intense aluminosilicate depolymerization—evidenced by the Al[VI] to Al[IV] coordination shift—and the quantitative integration of approximately 40% reactive iron phases into stable Fe-S-H networks. By clearly distinguishing between traditional hydration and clinker-free alkali-activation pathways, we evaluate holistic structural parameters beyond mere 28-day compressive strength (40–67 MPa), explicitly addressing flexural capacity, modulus of elasticity, and volume stability. Environmental assessments confirm exceptional heavy metal immobilization (>95% efficiency, leaching < 0.010 mg/L) and a substantial 50–80% reduction in Global Warming Potential (GWP), provided the environmental burden of alkaline activators is rigorously accounted for. Furthermore, the long-term risk of Alkali–Silica Reaction (ASR) is evaluated as a primary durability concern. Finally, to overcome persistent rheological bottlenecks, this paper highlights transformative future trajectories, particularly data-driven Machine Learning (ML) for complex mix optimization and 3D concrete printing for advanced infrastructure. Ultimately, this review provides a robust theoretical foundation and a pragmatic roadmap for upcycling RM into safe, high-performance, and ultra-low-carbon building materials. Full article

The obligate mutualism between Ficus and its pollinating wasps provides a suitable system to investigate these dynamics because it encompasses two contrasting pollination modes: active and passive. Here we compared pollen traits in an actively pollinated fig tree, Ficus citrifolia, and a passively pollinated species, F. obtusiuscula, examining pollen both at anther presentation and after deposition on the bodies of their pollinating wasps. Pollen morphology, hydration-related behavior, cytology, and reserve composition were characterized using scanning electron microscopy (conventional and modified), light and transmission electron microscopy, histochemical assays, and viability tests. Across species, pollen traits at anthesis showed broad overlap in morphology, viability and major reserve classes, indicating that these characteristics are not consistently predicted by pollination mode alone. In both species, pollen was bicellular, harmomegathic and highly viable at presentation, consistent with resilience during transport. The main divergence emerged after pollen transfer to the pollinator. In the actively pollinated species, pollen recovered from wasp thoracic pockets exhibited pronounced intracellular remodeling, including vacuolization, starch depletion, lipid redistribution and localized cytoplasmic degradation. By contrast, pollen of the passively pollinated species retained a comparatively stable cytological organization after transport despite changes in reserve distribution. These results suggest that the more pronounced cytoplasmic reorganization observed in the pollen of the actively pollinated species after deposition on the wasp body may represent a preparatory phase for rapid germination following pollination, reflecting the stronger dependence of larval development on successful flower fertilization in actively pollinated figs. More broadly, our study provides the first comparative account of pollen structural and cytophysiological dynamics on fig-wasp bodies, linking pollen cell biology to pollinator-mediated dispersal and highlighting how different pollination strategies may impose distinct selective pressures on male gametophytes. Full article

The recycling of waste clay bricks as raw materials for cement-based materials presents an effective solution to ecological pollution and resource shortages. Previous research has separately examined the effects of recycled brick fine aggregate and recycled brick powder on mortar or concrete, but few studies have investigated their combined use. This study aims to clarify the synergistic effect of recycled brick fine aggregate (RBA) and recycled brick powder (RBP) on mortar performance, quantify the influence of the RBP substitution rate on hydration characteristics and microstructural evolution, and determine the optimal mix proportion and curing system for fully recycled brick mortar. Mortar was prepared using 100% RBA and RBP at substitution rates of 0%, 10%, 20%, and 30%. The physical properties, mechanical performance, and durability of the mortar were evaluated, alongside an analysis of its microstructural morphology, mineral composition, and pore structure. The results indicate that adding an appropriate amount of RBP helped maintain the flowability of the mortar. As the RBP substitution rate increased, the mortar strength generally decreased in the early stages, but long-term curing (≥90 days) effectively mitigated this decline. The inclusion of RBP improved chloride ion permeability, with the 20% substitution rate achieving a favorable balance between compressive strength, fluidity, and durability without significantly affecting carbonation resistance. Microstructural analysis revealed that RBP regulated the morphology of hydration products and optimized the pore structure of the mortar, while the mineral composition of hydration products was similar to that of natural mortar. These findings provide a theoretical basis and technical support for the high-value utilization of construction and demolition waste in cement-based materials. Full article

The presence of impurities directly affects the properties of α-hemihydrate gypsum (α-HH) prepared from phosphogypsum (PG) as a raw material. However, the effect of soluble fluorine impurities on the properties of α-HH by autoclaving remains insufficiently understood. This study investigated the influence of sodium fluoride on the morphology, hydration, and hardening properties of α-HH, using XRD, XPS, SEM, MIP, and tests of setting time, evolution of hydration temperature increase, and strength. The results showed that during the preparation of α-HH, some F⁻ reacted with Ca²⁺ to form CaF₂, which adhered to the surface of the α-HH crystal, hindering the growth and development of the crystal and resulting in small crystals with rough surfaces. When α-HH hydrated, sodium fluoride caused the early, rapid nucleation of dihydrate gypsum (DH) crystals, accelerating the crystallization process of DH. The introduction of sodium fluoride inhibited the early hydration of α-HH and promoted its later hydration. The increase in sodium fluoride content caused the initial setting time of α-HH hydration to first increase and then decrease, while the final setting time continued to decrease. In the absence of sodium fluoride, the average pore diameter of the hardened paste was approximately 617.99 nm. When the NaF content was 0.2%, the DH crystals were prismatic and densely packed, which resulted in a decrease in the average pore diameter to 449.35 nm. When the NaF content was 0.6%, the DH crystals exhibited a plate-like morphology and were loosely interlocked, leading to an increase in the average pore diameter to 1169.58 nm. Based on these results, the sodium fluoride content in PG should be controlled below 0.2%. Full article

Conductive core–shell superabsorbent polymers (SAPs) are emerging as multifunctional additives for cementitious materials, combining moisture management with electrical functionality. In cement-based systems, a swellable polymeric core enables internal curing and crack-sealing through controlled water uptake and release, while a conductive shell introduces ionic and/or electronic charge transport, addressing key limitations of conventional non-conductive SAPs. This dual functionality provides a pathway toward smart cementitious composites with enhanced durability, self-sensing capability, and moisture-responsive behavior. This review focuses on the physical chemistry mechanisms governing conductive core–shell SAPs in cementitious environments, with emphasis on swelling thermodynamics, water transport kinetics, interfacial phenomena, and charge transport mechanisms. The roles of osmotic pressure, elastic network constraints, ionic effects, and pore solution chemistry are critically discussed, together with their impact on conductivity, hydration processes, microstructure development, and long-term performance. The relative contributions of ionic and electronic conduction are examined in relation to hydration state, shell morphology, and percolation of conductive networks. In addition, the relevance of core–shell SAP architectures to sustainable packaging is briefly discussed as a secondary application, illustrating how similar physicochemical principles—such as moisture buffering and functional coatings—apply beyond construction materials. Finally, key knowledge gaps are identified, including long-term stability in highly alkaline environments, trade-offs between swelling capacity and conductivity, environmental impacts of conductive phases, and the need for integrated experimental and modeling approaches. Addressing these challenges is essential for the rational design and practical implementation of conductive core–shell SAPs in next-generation cementitious materials. Full article

Wheat bran, as a major nutrient-rich agricultural by-product, is underutilized due to poor functional properties. This study investigated the synergistic effects of steam explosion (SE), enzymatic hydrolysis (EH), and SE combined with EH (SE-EH) on wheat bran to improve the dough properties, bread quality, and in vitro starch digestion. Results showed that SE destroyed the dense structure of wheat bran to form a porous surface morphology and promoted the conversion of insoluble dietary fiber (IDF) to soluble dietary fiber (SDF). This structural loosening facilitated further fiber degradation for subsequent EH and achieved the obvious improvements in hydration properties after combined treatment. For the dough system, the addition of SE-EH bran increased the water absorption, hardness, and viscosity, but reduced the development and stability time of the dough, in comparison with the control dough. These changes suggested that the modified bran altered dough hydration behavior and gluten network continuity, contributing to the increment of bread’s specific volume. The starch hydrolysis rate of bread adding SE-EH wheat bran was decreased; the slowly digestible starch (SDS) and resistant starch (RS) contents were 2.59-fold and 1.31-fold higher than the control group, respectively. Additionally, the incorporation of modified wheat bran delayed bread hardening during storage, with the SE-modified group showing the best effect. Wheat bran modification enhanced its processing functionality, providing a feasible approach for bread production to improve storage stability and nutritional quality. Full article

Epidermal Growth Factor (EGF) plays an important role in skin regeneration and repair by promoting cell proliferation and collagen synthesis. However, its topical application is limited by low stability, susceptibility to degradation, and poor penetration through the stratum corneum due to its hydrophilic nature and relatively large molecular size. Microencapsulation offers a strategy to protect sensitive bioactives and improve their delivery in cosmetic formulations. In this study, EGF was encapsulated in Arabic gum/gelatine A (AG/GE) coacervate microcapsules and incorporated into a hydrating cream. The work extends previous studies using the same microcapsule composition for lipophilic compounds, demonstrating its applicability for a hydrophilic bioactive and highlighting the versatility of the encapsulation platform. The resulting microcapsules exhibited spherical, multinucleated morphology with an encapsulation efficiency of 78.8 + 1.0%. Although diffusion of microencapsulated EGF in the cream could not be directly determined, the formulation showed trends towards improvement in several skin parameters during the volunteer evaluation, including reduction in surface spots (31%), brown spots (21%) and pore visibility (10%), and improved texture (22%). A 25% decrease in transepidermal water loss and a 33% increase in elasticity suggested improved skin barrier function. Volunteers reported high acceptance regarding non-irritancy, texture, and sensory experience. Full article

This study investigated the biosynthesis of magnetite nanoparticles mediated by chia mucilage (CM-Fe₃O₄ NPs) and their application in the co-encapsulation of Lactobacillus rhamnosus GG (LGG) using spray drying. CM-Fe₃O₄ NPs were synthesized by combining CM extract with iron salts, in which hydroxyl and carbonyl groups of CM acted as natural ligands for Fe²⁺/Fe³⁺ ions. A response surface design was applied to optimize synthesis parameters, focusing on size distribution and zeta potential, and confirming the influence of pH on colloidal stability. Characterization by FE-SEM, DLS, XRD, UV-Vis, and FTIR revealed spherical particles with an inorganic core (50–300 nm) and a hydrated organic coating (600–900 nm), consistent with a spinel structure functionalized by CM. Spray-drying encapsulation tests showed that incorporating CM-Fe₃O₄ NPs did not compromise bacterial viability, maintaining optimal moisture content and survival. Growth curves and confocal microscopy corroborated the physiological compatibility of the nanoparticles, with no alterations in LGG morphology or growth dynamics. Under simulated gastrointestinal conditions, co-encapsulated microcapsules exhibited slightly improved survival in the gastric phase and significantly greater viability in the initial intestinal phase. These results suggest that CM-Fe₃O₄ NPs modulate matrix degradation and promote controlled release, ensuring therapeutic concentrations of LGG in the intestine. Overall, the CM-Fe₃O₄ nanocomposite system integrates the protective properties of biopolymers with the functional advantages of iron nanoparticles, offering dual functionality: probiotic stabilization and potential iron supplementation. This innovative, food-grade approach supports the development of next-generation functional foods with combined therapeutic and nutritional benefits. Full article

Phyllanthus emblica (amla) exhibits anticancer activity, but its extracts often suffer from poor stability and bioavailability. This study developed amla extract-loaded niosomes to enhance delivery and evaluate their anticancer activity against MCF-7 and HCT116 cell lines, supported by in silico analyses. Methodology: Amla extract was prepared using a 50% aqueous–alcoholic solvent system and lyophilized. Niosomes were prepared by the thin-film hydration method and characterized for physicochemical properties. Anticancer activity was evaluated through in vitro cytotoxicity studies, supported by molecular docking and in silico pharmacokinetic analyses. Results: Optimized niosomes exhibited spherical morphology, good homogeneity (PDI < 0.30), anionic surface charge, high entrapment efficiency (70.5 ± 5.9%), and sustained diffusion-controlled release. In vitro cytotoxicity demonstrated a strong concentration-dependent anticancer activity of amla-loaded niosomes across a range of concentrations (31.25–1000 µg/mL) against both MCF-7 and HCT116 cell lines. At 1000 µg/mL, cell viability decreased to 7.0% and 5.4% in MCF-7 and HCT116 cells, respectively, with calculated IC₅₀ values of 245 µg/mL and 158 µg/mL. Molecular docking and pharmacokinetic predictions supported the potential multi-target anticancer relevance of major phytochemicals, including hydrolyzable tannins, phenolic acids, flavonoid aglycones and glycosides, and highlighted bioavailability limitations for certain high-affinity glycosylated flavonoids, reinforcing the rationale for vesicular encapsulation. Conclusions: Amla extract-loaded niosomes represent a promising vesicular system for enhanced, sustained delivery of anticancer activity in vitro, with complementary in silico findings supporting mechanistic plausibility and translational rationale. Further studies are warranted to evaluate their performance in vivo. Full article

Objectives: To evaluate the physicochemical properties of a novel strontium silicate-based root canal sealer (C-Root SP) in comparison with a calcium silicate-based sealer (TotalFill BC) and an epoxy resin-based sealer (AH Plus). Methods: Setting time, net mass change (apparent solubility behavior), pH changes, and surface characteristics were assessed based on ISO 6876 and ANSI/ADA Specification No. 57, with minor methodological modifications. Net mass change and pH were evaluated over 28 days. Surface morphology and elemental composition were analyzed after dry and aqueous aging in deionized water using scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy. Data were analyzed using one-way and repeated-measures ANOVA with Tukey’s post hoc test (α = 0.05). Results: AH Plus exhibited the longest initial and final setting times (10.93 ± 0.65 h and 37.33 ± 0.13 h), whereas TotalFill BC showed the shortest (7.98 ± 0.32 h and 30.18 ± 0.20 h); C-Root SP demonstrated intermediate values (9.35 ± 0.38 h and 32.75 ± 0.57 h) (p < 0.001). C-Root SP exhibited positive net mass change values (indicative of net mass loss), ranging from 5.32 ± 4.72% at 24 h to 6.83 ± 5.55% at 28 days, significantly higher than AH Plus and TotalFill BC (p < 0.001), which showed negative values indicative of apparent mass gain. All sealers demonstrated alkaline conditions, with C-Root SP maintaining the highest apparent pH values throughout the evaluation period (p < 0.001). Surface and compositional changes were observed in the bioceramic sealers following aqueous aging, with increased detectable strontium content in C-Root SP. Conclusions: C-Root SP exhibited physicochemical behavior consistent with a strontium-modified calcium silicate-based sealer, characterized by hydration-driven hydroxyl ion release resulting in apparent alkalinity and ion exchange-associated behavior, and dynamic surface changes consistent with those reported for bioceramic materials. Clinical Significance: Strontium incorporation may influence hydration-mediated physicochemical behavior; however, further in vitro and in vivo studies are required to determine its clinical relevance. Full article

The development of cementitious materials with multifunctional performance is increasingly important to address environmental demands and durability requirements in modern infrastructure. This study investigates calcium sulfoaluminate (CSA) cement partially substituted with blast furnace slag (BFS), fly ash (FA), and TiO₂ nanoparticles, aiming to combine sustainability with photocatalytic self-cleaning functionality. Phase analysis by X-ray diffraction confirmed the formation of characteristic CSA hydration products, including ettringite, ye’elimite, anhydrite, and calcite, indicating that partial substitution did not disrupt the primary hydration mechanisms. Microstructural observations revealed that the incorporation of BFS, FA, and TiO₂ induced noticeable morphological changes, with increased porosity and microstructural heterogeneity at higher replacement levels. Mechanical testing showed that moderate BFS contents of 5 to 10 wt% enhanced compressive strength in reference mixtures, while systems containing TiO₂ exhibited slightly lower strength values and increased dispersion, particularly at elevated slag contents. The photocatalytic performance, evaluated through Rhodamine B degradation under solar irradiation, demonstrated a marked improvement for TiO₂-containing samples, reaching degradation efficiencies of up to 80%, in contrast to negligible activity in unmodified systems. These results confirm that the combined use of industrial by-products and photocatalytic nanoparticles in CSA-based matrices represents a viable strategy for producing sustainable cementitious materials with added environmental functionality, without compromising fundamental structural performance. Full article

Fluid seepages and seabed pockmarks are widely observed on continental margins worldwide in hydrate- and non-hydrate-bearing sediment. Subsurface gas chimneys connecting seafloor pockmarks to underlying gas reservoirs are commonly revealed by seismic reflection data, indicating pathways of past and present fluid migration. Fluid seepage occurs when the seal of a gas reservoir is breached, allowing fluids to migrate upward and vent at the seafloor, forming pockmarks. In hydrate-bearing settings, gas reservoirs beneath hydrate layers typically consist of coexisting water and gas phases. However, quantitative constraints on gas saturation in free-gas zones beneath hydrates inferred from pockmark morphology remain limited. In this study, a two-phase pockmark model was developed to investigate gas-chimney growth and pockmark formation, and to estimate gas saturation in free-gas zones below hydrates using pockmark depth and gas-zone thickness as key parameters. The model was applied to the Storegga Slide region off Norway, where hydrates, pockmarks, and chimney-like seismic anomalies have been documented. Here, the application is intended to represent localized near-threshold (pre-seepage) conditions leading to pockmark initiation, rather than the present-day post-venting state. Model results for the initiation (near-threshold, pre-venting) stage indicate that the effective gas saturation in the free-gas reservoir beneath the hydrates was approximately 1.36–1.58% for gas-zone thicknesses of 50–100 m, and that the corresponding chimney-propagation timescale during initiation was on the order of ~200 years. These estimates represent threshold conditions required for seal breach and pockmark formation rather than present-day seepage states. During venting, methane gas may form hydrates within the chimney inside the hydrate stability zone, while authigenic carbonates precipitate in pockmarks and shallow sediments. These secondary hydrates and carbonates eventually seal the chimney, leaving behind a residual gas chimney in the subsurface sediment. Full article

Foaming technology can effectively reduce the viscosity of polymer-modified asphalt and significantly decrease energy consumption during pavement construction, making it an effective approach for achieving low-carbon pavement construction and maintenance. However, mechanically foamed asphalt relies on specialized equipment and requires strict parameter control. Although water-based foaming methods using zeolites or ethanol can alleviate these issues to some extent, they still present disadvantages such as significant variability in foaming performance and potential risks during transportation and construction. Therefore, this study investigates the feasibility of using crystalline hydrates with high water of crystallization for micro-foamed asphalt. Three types of micro-foamed SBS-modified asphalt (MFPA) were prepared using hydrates with different contents of water of crystallization. Physical property tests, foaming characteristic parameters, viscosity–temperature analysis, Fourier transform infrared spectroscopy (FTIR), adhesion tensile tests, scanning electron microscopy (SEM), and fluorescence microscopy were conducted to evaluate their effects on the physical and chemical properties, viscosity reduction performance, adhesion, and compatibility of SBS-modified asphalt. Furthermore, dynamic shear rheometer (DSR) tests, bending beam rheometer (BBR) tests, fatigue life modeling, and morphological analysis were employed to investigate the rheological properties, fatigue life, and bubble evolution behavior of the MFPA system. The results indicate that utilizing the thermal decomposition characteristics of crystalline hydrates with high water of crystallization (Na₂SO₄·10H₂O, Na₂HPO₄·12H₂O, and Na₂CO₃·10H₂O) to release H₂O and CO₂ in SBS-modified asphalt for micro-foaming is a short-term reversible physical viscosity reduction process. The maximum expansion ratio (ERmax) of MFPA reaches 8–10, the half-life (HL) remains stable at approximately 180 s, and the foaming index (FI) peak is about 1160. The construction temperature can be reduced by 10–15%, and the viscosity reduction effect remains stable within 60 min. Compared with unfoamed SBS-modified asphalt, the compatibility, rutting resistance, and fatigue life of MFPA increase by approximately 65%, 32%, and 30%, respectively, while the low-temperature performance decreases by 18%. Under the same short-term and long-term aging conditions, MFPA exhibits better aging resistance. Specifically, its rutting resistance increases by 37%, and fatigue resistance improves by 30% compared with aged SBS-modified asphalt, while the low-temperature performance remains essentially unchanged. Full article

Calcium silicate hydrate (C(-A)-S-H) and its aluminosilicate counterpart (C-A-S-H) constitute the principal binding phases in Portland cement and blended systems, governing mechanical strength and durability. This paper presents a summary of the work related to dehydration of C(-A)-S-H and rehydration of dehydrated C(-A)-S-H. Their thermal dehydration, a key process for cement recycling, induces profound multi-scale transformations: at the atomic level, it alters calcium and aluminum coordination environments and disrupts chemical bonding; at the chain-structure level, it causes depolymerization of the silicate/aluminosilicate networks; and at the microstructural level, it leads to changes in nanoscale particle morphology, aggregation state, and pore structure, creating a metastable, defect-rich, high-energy state distinct from the original C(-A)-S-H. The subsequent rehydration of this dehydrated C(-A)-S-H, which is not a simple reversal but a distinct dissolution–precipitation process, enables microstructural reconstruction and restored reactivity upon contact with water. This rehydration capacity is fundamentally exploited in thermally activated recycled cement—a novel binder concept that leverages dehydration-induced metastability for renewed strength development. Understanding these interconnected processes, influenced by factors like temperature, humidity, rate, and aluminum content, is critical for advancing sustainable cement technology, enabling the design of high-performance recycled cement and concrete, and facilitating the recycling of cementitious materials. Full article