Search Results (6,267)

Walnut kernels are highly susceptible to lipid oxidation because of their high content of unsaturated fatty acids. This study screened five lipid-soluble antioxidants—tert-butylhydroquinone (TBHQ), butylated hydroxytoluene (BHT), propyl gallate (PG), dilauryl thiodipropionate (DLTP), and ascorbyl palmitate (AP), and further evaluated binary and ternary formulations based on BHT. Treated walnut kernels were subjected to accelerated oxidation, and the oxidative stability was assessed using peroxide value, thiobarbituric acid-reactive substances (TBARS), DPPH radical scavenging activity, electron spin resonance, fatty acid composition, thermogravimetric analysis, and sensory evaluation. Among the individual antioxidants evaluated at their respective maximum permitted concentrations, BHT showed the most consistent protective effect, with the lowest oxidation indices, the strongest DPPH radical scavenging activity, and the weakest thermally induced radical signal. The BHT + TBHQ formulation performed significantly better than BHT alone in several oxidation indices (p < 0.05). The ternary BHT + TBHQ + DLTP formulation showed the best overall performance, with antioxidant activity comparable to that of the commercial antioxidant blend and significantly lower TBARS values than the BHT + TBHQ group (p < 0.05). Linoleic, oleic, and α-linolenic acids remained at 58.78–62.54%, 17.62–21.33%, and 10.64–11.31%, respectively. No significant differences in aroma or flavor were observed among treatments (p > 0.05). These findings indicate that BHT + TBHQ + DLTP effectively improves the oxidative stability of walnut kernels during accelerated storage. Full article

A nonionic type V deep eutectic solvent (DES) combining hydrophobic (−)-menthol and hydrophilic resorcinol was prepared and investigated as a solvent for amphiphilic caffeine. Differential scanning calorimetry and thermogravimetric analysis were first used to determine the eutectic composition and characterize its thermal behavior. The menthol-to-resorcinol molar ratio of 2:1 was subsequently selected for physicochemical investigation. Clear homogeneous solutions containing up to 0.701 mol·kg⁻¹ caffeine were prepared, corresponding to 136 g of caffeine per kilogram of DES. Density, speed of sound, and viscosity were measured over the temperature range from 293.15 to 313.15 K. These data were used to evaluate the thermal expansion, volumetric and acoustic properties, intermolecular free length, and concentration and temperature dependences of viscous flow. The viscosity results were further analyzed using the Arrhenius, Jones–Dole, and Eyring–Feakins approaches and compared with the behavior of caffeine in water, ethylene glycol, and methyl salicylate. DFT calculations and molecular electrostatic potential surfaces were used to examine the local organization of the DES and the possible incorporation of caffeine through interactions with both its polar and less-polar regions. The combined experimental and computational approach provides a molecular and thermodynamic basis for evaluating this DES as a caffeine-solubilizing and delivery medium. Full article

This work presents the design of a novel multi-component surface-coating system incorporating expandable graphite (EG), ammonium polyphosphate (APP), aluminium tri-hydroxide (ATH), alginate, and D-glucosamine hydrochloride (DGH). Importantly, the coated polyurethane (PU) foams demonstrated performance within the corresponding Hazard Level 3 limits for the measured parameters, including Maximum Average Rate of Heat Emission (MARHE), smoke density, and toxicity, providing preliminary indications of their potential for railway fire safety applications. Systematic variations in EG loading revealed substantial improvements in flammability metrics, with the EG-rich formulation achieving a limiting oxygen index (LOI) of 73%, MARHE of 18 kW m⁻², and significantly reduced smoke production. EG transformed the fire behaviour even at high external heat fluxes from flaming to self-extinguishing and only smouldering, promoting rapid formation of a dense, thermally insulating char. Combined interactions between EG, inorganic, and biobased additives reinforced char integrity, suppressed degradation rates, and enhanced condensed-phase protection. Thermogravimetric analysis confirmed increased residue yields (up to 52 weight percentage at 600 °C). Overall, this multi-functional coating offers a cost-effective, low-toxicity strategy for producing flame-resistant PU foams for demanding transportation and construction applications. Full article

Backgorund/Objectives: Respiratory diseases represent a substantial global health burden and require effective localised pulmonary delivery strategies, particularly for poorly water-soluble therapeutic molecules. Nanoparticle-based drug delivery systems, especially those manufactured using microfluidics, have emerged as promising approaches to overcome pulmonary barriers, enhance local drug retention, and reduce systemic side effects. Among these nanocarriers, solid lipid nanoparticles (SLNs) and solid hybrid nanoparticles (SHNs) combine biocompatibility with controlled release and improved formulation stability. Methods: In this study, SLNs and lipid–chitosan SHNs were developed using microfluidic technology as candidate platforms for pulmonary drug delivery, with Cyclosporine A (CyA) used as a model hydrophobic cyclic peptide. Nanocarriers were produced using 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and cholesterol as lipids, with low-molecular-weight chitosan incorporated to obtain hybrid systems. Physicochemical properties were evaluated using dynamic light scattering (DLS) and ζ potential measurements, while morphology and structural organisation were investigated using transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). Results: The microfluidic approach enabled the production of nanoparticles with controlled sizes below 200 nm, narrow size distributions, and good reproducibility. In addition, the SHNs exhibited a positive surface charge, high encapsulation efficiency (~80%), and good colloidal and thermal stability. In vitro release studies showed an initial burst release followed by sustained CyA release, reaching approximately 94% cumulative release within 6 h. The Korsmeyer–Peppas model was used as the standard kinetic model. No blank nanoparticles were used as controls in the EE and release assay. Conclusions: Overall, these findings support further investigation of microfluidic-produced lipid and hybrid nanoparticles as candidate platforms for pulmonary drug delivery. Full article

Conventional partially hydrolyzed polyacrylamide (HPAM) suffers severe chain coiling, viscosity attenuation and precipitation under high-temperature and high-salinity reservoir brines, restricting its tertiary oil recovery efficiency. Herein, a novel carbon quantum dot hybrid terpolymer (QDHSTP) was synthesized via free-radical copolymerization, where silane-modified nitrogen-doped carbon quantum dots (FNCQDs) were covalently bonded to acrylamide (AM)/2-acrylamido-2-methylpropane sulfonic acid (AMPS)/diallyldimethylammonium chloride (DMDAAC) backbones. FTIR, ¹H NMR and thermogravimetric analysis (TGA) verified successful grafting of FNCQDs, while SEM revealed a continuous three-dimensional entangled network constructed by polymer chains. Steady and oscillatory rheology systematically characterized the solution viscoelasticity: QDHSTP solutions followed the power-law shear-thinning model, with flow behavior index n decreasing from 0.698 to 0.676 and consistency factor k rising from 80.91 to 131.13 mPa·sⁿ as concentration increased from 2000 to 3000 mg/L. All samples behaved as viscosity-dominated viscoelastic fluids, with elastic modulus exhibiting stronger frequency dependence. Benefiting from embedded FNCQDs, QDHSTP retained 79.74% and 76.06% of initial viscosity in 1.0 × 10⁴ mg/L NaCl and CaCl₂ brine, respectively, markedly better than that of the polymer without incorporated FNCQDs respectively, and maintained thickening capacity at 90 °C. Artificial sandstone core flooding demonstrated an incremental oil recovery of 29.8% over baseline waterflooding, attributed to mobility control and elastic residual oil stripping. This covalent nanohybrid strategy provides a facile route to construct thermo-salt tolerant polyacrylamides, offering a promising candidate polymer for harsh oil reservoir chemical flooding. Full article

Background/Objectives: Bisoprolol fumarate (BF) is a cardioselective beta-blocker used to treat pediatric heart failure and certain tachyarrhythmias. Currently, it is administered mainly as extemporaneously prepared suspensions from crushed tablets, which may cause issues with dose accuracy, stability, and palatability. Orodispersible minitablets (MODTs) may facilitate administration and individualized dosing, while prolonged release could potentially reduce peak-to-trough fluctuations and, thus, minimize adverse effects such as hypotension or bradycardia. This proof-of-concept study aimed to develop spray-dried prolonged-release microparticles containing BF, incorporate them into MODTs, and evaluate the effect of compression on drug release. Methods: Microparticles were prepared by spray drying ethanolic solutions of BF and ethylcellulose at 40 °C, 50 °C, and 60 °C. Their characterization included scanning electron microscopy, X-ray diffraction, differential scanning calorimetry, thermogravimetric analysis and dissolution studies. Selected microparticles were compressed into 3 mm MODTs, which were evaluated for mechanical properties, disintegration, and BF release. Results: Formulations containing 10% BF and 90% ethylcellulose released from 52.6% to 73% of BF after 2 h, increasing to 84.8–90.0% after 8 h and reaching 96% after 24 h. Solid-state analyses indicated complete amorphization of the drug in these microparticles. The spray-drying temperature affected process efficiency but did not significantly impacted morphology or dissolution behavior. The optimized MODTs disintegrated in less than 30 s and had a tensile strength of up to 2.62 MPa. Importantly, compression increased the initial BF release from 26.4% for the microparticles to 43.9% for the MODTs at 0.5 h, resulting in f₂ values of 45.04–48.46. Despite the higher initial BF release, the moderately prolonged-release profile was maintained in the case of MODTs. Conclusions: These findings demonstrate the feasibility of combining prolonged-release microparticles with orodispersible minitablets as a proof-of-concept for a pediatric drug delivery approach. Full article

Gasification is a route for cattle manure resource utilisation and emission mitigation, but its mass-change mechanism under an O₂/H₂O atmosphere remains unclear. This work aims to reveal the staged apparent mass-gain behaviour and its underlying coupling mechanism during cattle manure thermochemical conversion under O₂/H₂O atmospheres, so as to provide support for biomass gasification process optimisation and industrial circulating fluidised-bed gasifier parameter regulation. Thermogravimetric (TG) experiments were conducted under five O₂:H₂O mass ratios (1:4, 1:2, 1:1, 2:1 and 4:1), set with reference to the typical gas–steam ratio of circulating fluidised beds, combined with four heating rates (5, 10, 15 and 20 °C min⁻¹), and the mass-change behaviour was interpreted using multiple characterisation techniques. The strongest peak appeared at 634 °C at an O₂:H₂O mass ratio of 1:2 and a heating rate of 10 °C min⁻¹, with a maximum mass-gain rate of 11.0% min⁻¹. The main mass-loss peaks occurred between 242 and 291 °C and were associated with organic-structure cracking and volatile release. The medium-temperature (297–457 °C) mass gain was attributed to oxidative adsorption on active char surfaces and transient oxygen-containing intermediates, whereas the high-temperature (521–864 °C) response was linked to ash mineral restructuring and char–mineral interfacial reactions. Full article

The increasing adoption of additive manufacturing in the construction sector has intensified the demand for lightweight, recyclable cement-based composites with low environmental impact, suitable for automated 3D printing. Foamed concrete reinforced with dispersed fibers and incorporating recycled constituents represents a promising class of multifunctional materials. However, its environmental performance remains insufficiently characterized. This study provides a comprehensive evaluation of thermal stability, leaching behavior, and microbial resistance of 3D-printable fiber-reinforced foamed cement composites produced with recycled components. Thermogravimetric–Fourier transform infrared (TG–FTIR) analysis confirmed a characteristic three-stage thermal decomposition pathway typical of hydrated cementitious systems. All composites exhibited high thermal stability, with residual masses of 88.56–90.17% at 900 °C. The binder type exerted a stronger influence on decomposition behavior than atmospheric exposure or freeze–thaw conditioning. Leaching tests revealed strongly alkaline eluates (pH 11.0–11.4), low total organic carbon (<0.6 wt.%), and only trace concentrations of BTEX (35–41 μg/kg), PAHs, and PCBs. Alkali activation increased the release of chromium (3.6–4.0 mg/kg), arsenic (1.2 mg/kg), copper (4.5 mg/kg), antimony (0.26 mg/kg), and sulfates (2700–4700 mg/kg), accompanied by elevated total dissolved solids (~18,000 mg/kg). Nevertheless, all environmentally relevant constituents remained well below the waste acceptance criteria (WAC), confirming effective immobilization of hazardous species within the hardened matrix. The results provide new insights into the relationships among material composition, porous microstructure, and environmental safety, demonstrating that the developed 3D-printable foamed composites exhibit robust performance, suitability for safe and durable applications, and favorable environmental performance. Full article

This study presents a comparative thermochemical and combustion analysis of biomass pellets derived from softwood, hardwood, sunflower husks, wheat straw, and lavender residues. This investigation was performed using thermogravimetric analysis (TG), derivative thermogravimetric analysis (DTG), and differential scanning calorimetry (DSC) to evaluate the thermal degradation behavior, combustion reactivity, heat-release characteristics, and ash-forming tendencies of the investigated biomass types. The results revealed substantial differences between woody biomass and agricultural residues in terms of thermal stability, thermal degradation behavior, and energy output. Softwood pellets exhibited the highest thermal reactivity, the most intense devolatilization process, and the highest heat release during combustion, indicating higher thermal reactivity and favorable fuel properties. Hardwood pellets demonstrated improved thermal stability due to increased lignin content, resulting in broader thermal decomposition regions and more gradual heat release. In contrast, sunflower husk and wheat straw pellets showed lower thermal reactivity and significantly higher residual mass, indicating elevated ash content and reduced thermal decomposition behavior. Lavender pellets exhibited intermediate thermochemical behavior associated with the presence of volatile extractives and moderate thermal stability. The integrated TG-DTG-DSC approach enabled a direct comparison of woody biomass and agricultural residues under identical experimental conditions and expanded the available thermochemical data for lavender-derived pellets. The results provide a comparative framework for assessing biomass resources intended for energy applications. Full article

Hyaluronic acid (HA) is a high-molecular-weight glycosaminoglycan whose cross-linked hydrogels are widely used as injectable fillers; their controlled degradation is clinically important but, in practice, achievable only enzymatically with hyaluronidase. Here we compared the enzymatic, ultrasonic and photothermal degradation of a single cross-linked HA macromolecular network and characterised the resulting structural, thermal and chromatographic changes. A cross-linked HA hydrogel (Regenyal Idea, 25 mg/mL) was embedded in an ex vivo porcine skin matrix and treated in six groups: untreated control; hyaluronidase; microfocused ultrasound (7 MHz, 3 mm focal depth); and irradiation with 1064 nm Nd:YAG, diode or alexandrite lasers. Degradation was characterised by FT-IR spectroscopy, thermogravimetric analysis (TGA) and high-performance liquid chromatography (HPLC). FT-IR showed retention of the HA backbone with partial loss of the cross-linked network, while TGA revealed treatment-dependent decreases in thermal stability. By HPLC, hyaluronidase released the most soluble HA (58.2 ± 2.9% at day 1; ~88% plateau by day 2). Among the energy-based methods, only the 1064 nm Nd:YAG laser produced comparable degradation (57.3 ± 5.2%), whereas microfocused ultrasound, the diode and the alexandrite lasers released little soluble HA (3.2–5.3%). The wavelength dependence is consistent with a water-mediated photothermal scission of the HA chains. These findings identify long-pulsed 1064 nm irradiation as an effective non-enzymatic route to degrade the cross-linked hyaluronic acid macromolecule, with hyaluronidase remaining the reference standard. Full article

The growing demand for multifunctional textile materials has stimulated extensive research into the development of antimicrobial finishing agents capable of providing long-term protection against pathogenic microorganisms while preserving the performance characteristics of fabrics. In this study, cotton fabrics were functionalized using a nitrogen- and sulfur-containing antiseptic composition based on sulfosalicylic acid, copper acetate treated fabrics were characterized by Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA/DTG) to investigate their structural, morphological, and thermal properties. The antimicrobial activity of the modified fabrics was evaluated against representative microorganisms. In addition, the influence of the antiseptic treatment on the functional properties of the cotton fabrics, including tensile strength, elongation at break, wrinkle resistance, abrasion resistance, hygroscopicity, air permeability, color fastness, and water permeability, was assessed. The results demonstrated successful incorporation of the antiseptic composition onto the fiber surface, improved thermal stability, and pronounced antimicrobial activity. Furthermore, the treated fabrics retained satisfactory mechanical and hygienic properties, indicating the suitability of the developed composition for the production of protective and hygienic textile materials. The proposed approach offers a promising route for the fabrication of multifunctional cellulose-based textiles with enhanced performance and biological protection. Full article

To promote the value-added circular utilization of coastal driftwood, a single salt-exposed driftwood specimen was thermally converted into porous carbon materials by slow pyrolysis. Highly porous carbons are attractive for applications such as adsorption and catalyst support because accessible micro- and mesopores provide a large interfacial area. Prior to carbonization, the thermochemical characteristics of the driftwood were evaluated by proximate analysis, elemental analysis, calorific-value determination, and thermogravimetric analysis (TGA). Pyrolysis was conducted at 400, 500, 600, 700, and 800 °C with residence times of 0, 30, and 60 min at a heating rate of 10 °C/min. The crude biochar products were subsequently washed with reverse-osmosis water. Carbonization temperature was the principal process variable governing pore development. The condition producing the maximum measured porosity was 800 °C with a 60 min residence time, for which the crude biochar yield was 22.98 wt%. The instrument-reported BET surface area and total pore volume of DW-800-60 were 777.5 m²/g and 0.47 cm³/g, respectively. Re-evaluation of the same N₂ isotherm using the Rouquerol consistency criteria gave a physically consistent BET estimate of approximately 944.0 m²/g over P/P₀ = 0.0051–0.0597. Gas adsorption indicated a predominantly microporous structure with an additional mesoporous contribution, whereas the scanning electron microscope (SEM) showed inherited micrometer-scale wood channels. DW-800-60 contained 87.6 wt% carbon. Because the botanical species and mineral-salt composition were not identified and practical adsorption or catalytic performance were not tested, the results should be regarded as specific to the investigated specimen and as a basis for future application-oriented evaluation. Full article

In this research, the catalytic pyrolysis properties, kinetics, thermodynamic characteristics, and composition of the vapor evolved from the thermal decomposition of copper-incorporated nylon fishing net (CuFN) waste were investigated. The analysis was performed on CuFN composed mainly of nylon and copper (3 wt.%) as an anti-corrosion element. A comparative catalytic study was conducted using two types of zeolite catalysts, ZSM-5 (CuFNz) and Y-type (CuFNy). Reaction complexity in the presence of both catalysts was investigated through linear and nonlinear kinetic approaches, along with estimation of the relevant thermodynamic parameters. In addition, a well-trained artificial neural network was used to predict the catalytic thermal decomposition properties of both batches under untested heating conditions. Thermogravimetric results indicated that the catalyst type moderately influenced the decomposition profiles, with CuFNz achieving complete decomposition at 495 °C (44 wt.%), compared to 475 °C (52 wt.%) for CuFNy. Also, the type of catalyst did not affect the functional groups in TG-FTIR, which showed two main peaks at 1712 cm⁻¹ (Carbonyl group) and 2933 cm⁻¹ (C-H stretching band), but the alkyl C-H band was dominant in the case of CuFNy. Meanwhile, gas-chromatography–mass-spectrometry results indicated that caprolactam (88.21%) was a major GC compound in the CuFNz sample and 5-Cyano-1-pentene (70.43%) was dominant in the vapor of the CuFNy sample. However, the presence of the catalyst increases the complexity of the reaction, reflected by higher pyrolytic activation energies of 244.8 kJ/mol (CuFNz) and 296.3 kJ/mol (CuFNy). Moreover, the mysterious catalytic thermal decomposition of CuFN was fully recognized by the optimized ANN algorithm with R = 1. The study demonstrates that catalytic pyrolysis can convert CuFN into valuable products, including caprolactam using a ZSM-5 catalyst and 5-Cyano-1-pentene using a Y-type catalyst, potentially leading to significant environmental and economic benefits. Full article

Cadmium contamination in water poses a serious environmental and health concern due to its high toxicity and persistence. In this context, the development of efficient and low-cost adsorbent materials has attracted increasing attention. This work examines the removal of Cd(II) from aqueous solution using a cellulose acetate–clay composite membrane as an adsorbent material. To evaluate the impact of clay inclusion, membranes were fabricated with varying clay concentrations (0%, 12.5%, and 25%). A Box–Behnken design was used to optimize the process; thermogravimetric analysis, X-ray diffraction, and Fourier-transform infrared spectroscopy were used to analyze the produced composite membranes. The characterization results confirmed the successful incorporation of clay into the cellulose acetate matrix and revealed important changes in the membrane structure and surface morphology. The adsorption performance was strongly affected by operating conditions, particularly temperature, contact time, and clay content. Under the optimal conditions of 30 °C, 4 h, and 5% clay content, the CA-Clay composite membrane achieved a maximum Cd(II) removal efficiency of 93.93% and an adsorption capacity of 12.35 mg/g. These results demonstrate that the composite membrane has a high affinity toward Cd(II) ions, exhibiting its high potential as a low-cost and efficient adsorbent for the removal of Cd(II) from aqueous solution. Full article

With rapid development of 5G/6G communication and high-power electronic devices, electromagnetic interference (EMI) shielding textiles are urgently required to mitigate electromagnetic pollution. Traditional metallic shielding suffered from heavy weight, poor corrosion resistance, and secondary electromagnetic reflection, while continuous basalt fibers (CBFs) exhibit excellent mechanical strength, lightweightness, thermal/chemical resistance, and electrical insulation, which makes CBFs ideal substrates for EMI devices. Herein, a multifunctional waterborne polyurethane (WPU) sizing agent (coating emulsion) integrated with Mn-Zn spinel ferrite was developed for in situ lubrication on the as-spun CBFs. The composite sizing agents consisted of a WPU matrix, water-soluble epoxy, mineral oil lubricant, CTAB surfactant, KH-570 coupling agent, and micro-sized Mn-Zn ferrites. Characterizations including particle size distribution, thermogravimetric analysis, water contact angle (WCA), water absorption, FTIR, XRD, and SEM were conducted to verify uniform anchoring of ferrites on the CBF surfaces. Increasing ferrite dosages induced slight particle aggregation, elevated surface hydrophobicity (WCA = 42.4° → 99.43°), and reduced water absorption (65% → 35%), which greatly improved the moisture resistance of the CBFs. The X-band EMI shielding tests revealed that the total shielding effectiveness (SET) of modified CBF fabrics increased from 0.11 dB (pristine fiber without ferrite) to 58.57 dB at a loading of 8.0 g/L ferrite. The absorption loss (SEA) dominated the shielding performance over reflection loss (SER). The low-to-moderate contents (1.5–3.0 g/L) of ferrite achieved ultra-high absorption, while higher ferrite loading (5.0–8.0 g/L) intensified the impedance mismatch and enhanced surface reflection. This work establishes a scalable fabrication of absorption-prioritized lightweight CBF shielding, which provides a feasible pathway for flexible EMI shielding textiles. Full article