Antimicrobial resistance and biofilm-associated infections present major challenges in oral healthcare, necessitating sustainable nanomaterials with multifunctional efficacy. This study reports the green synthesis of zinc oxide nanoparticles (ZnO NPs) from Pergularia daemia (P. daemia) fibre (PDF) extracts and evaluates their structural, thermal, and biological properties for dental and biomedical applications. ZnO NPs were synthesised using aqueous PDF extracts as natural reducing and stabilising agents. Structural crystallinity was examined by X-ray diffraction (XRD), functional groups by Fourier-transform infrared spectroscopy (FTIR), morphology by scanning electron microscopy (SEM), and thermal stability by thermogravimetric analysis (TGA). Antibacterial performance against Klebsiella pneumoniae and Streptococcus mutans was assessed via agar well diffusion, while antibiofilm efficacy was evaluated using confocal laser scanning microscopy (CLSM). XRD confirmed a semi-crystalline ZnO phase with a crystallite size of 28.6 nm and a crystallinity index of 21%. FTIR revealed hydroxyl, carbonyl, and carboxylate groups contributing to nanoparticle stabilisation. SEM micrographs showed irregular, porous, and agglomerated morphologies spanning nanometre to submicron scales. TGA indicated multi-step degradation with a stable residual fraction of ∼14% at 670 °C. Antibacterial assays demonstrated strong inhibition zones (27 mm, 32 mm at 75 µg; 31 mm, 41 mm at 100 µg), comparable to streptomycin (34 mm and 43 mm). CLSM confirmed significant antibiofilm activity through membrane disruption and reduced bacterial viability. The enhanced antibacterial and antibiofilm performance of PDF-derived ZnO NPs arises from synergistic effects of nanoparticle cores, reactive oxygen species generation, and phytochemical surface functionalization. Their stability and bioactivity underscore their promise as sustainable nanomaterials. PDF-mediated ZnO NPs show potential for dental applications, including caries prevention, root canal disinfection, and biofilm-resistant coatings for restorative and implant materials. Their multifunctional profile further supports broader biomedical use in antimicrobial therapy, drug delivery, and composite engineering.

Agricultural HDPE pyrolysis for environmental management: Feedstock complexity, reaction dynamics, and circular resource recovery.

Mesalamine premix-based delayed release formulation and its efficacy assessment using a 3D in-vitro gut model for inflammatory bowel disease.

Synthesis, structural characterization, computational studies, and anticancer evaluation of novel rufloxacin Schiff base metal complexes with involvement of Mcl-1 modulation in breast cancer cells.

Bio-upcycling of bioplastic wastes into polyhydroxyalkanoates.

High-pressure solid-state (mechanochemistry) synthesis of corn starch tartrates.

The accumulation of plastic waste, particularly from high-density polyethylene (HDPE) and polyethylene terephthalate (PET), poses significant environmental challenges due to their persistence and the complexity of recycling mixed polymer. Accordingly, this study was conducted to investigate the thermal degradation behavior and kinetic parameters of virgin HDPE, PET, and their binary mixture to support waste-to-energy applications. Thermogravimetric analysis (TGA) and Differential thermogravimetry (DTG) were performed under pyrolytic conditions using nitrogen as the carrier gas at multiple heating rates, and degradation kinetics were evaluated using five isoconversional methods: Friedman (FR), Kissinger–Akahira–Sunose (KAS), Flynn–Wall–Ozawa (FWO), Starink (STK), and Vyazovkin (Vy). Results showed that both HDPE and PET undergo single-step degradation, with HDPE decomposing at higher temperatures in a narrower range (449–497 °C) than PET (394–471 °C) at 15 °C/min. The HDPE–PET blend showed a broader decomposition range (417–495 °C) with an onset temperature between PET and HDPE. Comparatively, the Friedman (FR) method provided reliable activation energies for HDPE and PET (259.55 ± 7.3 and 193.16 ± 17.07 kJ/mol), as it effectively captures the single-step degradation of individual polymers with minimal variation across conversion levels. For the HDPE–PET binary blend, the Vyazovkin (Vy) method yielded the most consistent activation energy profile (173.51–217.45 kJ/mol; average 210.47 ± 7.2 kJ/mol), demonstrating its robustness in handling the complex, overlapping decomposition behaviors of mixed polymer systems. Model-fitting via y(α)/y(0.5) analysis identified the autocatalytic model 1 − α n α m + α ∗ as the most appropriate for all samples, with simulated curves showing excellent agreement with experimental data (R 2 > 0.92). These findings demonstrate the feasibility of predicting pyrolysis behavior for both individual and mixed plastics, contributing to improved strategies for managing mixed plastic waste streams. • At β = 15 °C/min, the HDPE–PET blend showed a broader decomposition range (417–495 °C). • Eα by Fr averaged 259.55 kJ/mol for HDPE, 193.16 kJ/mol for PET, and Vyazovkin 210.47 kJ/mol for the blend. • The autocatalytic model obtained the f(α) for degradation kinetics for HDPE, PET, and their blend. • Simulated autocatalytic model curves matched experimental data (R 2 > 0.92),

Dendritic mixed-mode stationary phases prepared by thiol-epoxy click reaction for the determination of bisphenols in a variety of complex samples.

Biopolymers, particularly polysaccharides such as pectin, chіtosan and alginate, offer significant potential in addressing numerous current environmental and health issues. In contrast to synthetic polymers, natural polysaccharides possess valuable properties such as biodegradability, biocompatibility, and non-toxicity. Due to that, they have proven their efficiency in biomedical applications for drug encapsulation and delivery, wound healing and tissue engineering. Moreover, their natural origin and environmental compatibility make them highly suitable for applications in agriculture, particularly in soil conditioning and remediation. These well-known, commercially available biopolymers have unique functional properties which, when combined, can improve their physicochemical properties synergistically. Methods of Calcium Alginate and mixed polysaccharides based on Alginate and Pectins A and LM synthesis in the form of spherical beads with adjustable diameter were developed, and the influence of the nature and concentration of the components on their properties was analysed. The morphology of the synthesized polysaccharide gels (based on Alginate, Alginate-Pectin A and Alginate-Pectin LM) was examined by means of electron microscopy (SEM), while their chemical structure was confirmed by FTIR. The elemental composition of the synthesised polysaccharides was studied using energy-dispersive X-ray spectroscopy (EDX), while their thermostability and thermolysis processes were analysed using thermogravimetric analysis. It was demonstrated that the synthesised polysaccharide beads could withstand steam sterilisation at 121 °C without undergoing significant changes. This opens up the possibility of using them in various biomedical technologies. Studying the swelling kinetics of polysaccharide gels in different solvents (water, saline and phosphate-buffered saline (PBS)) enabled us to determine their inherent Fick diffusion type. The developed mixed polysaccharides show promise as a synthetic soil conditioner for agricultural use and for targeted delivery and controlled release of medicine.

In the present study, an exopolysaccharide (EPS)-producing bacterial strain was isolated and identified as Sphingobium yanoikuyae SS02 using 16S rRNA gene sequencing. Optimization of the culture medium through a one-factor-at-a-time (OFAT) approach enhanced EPS yield to 6.5 ± 0.2g/L under mesophilic conditions. The purified EPS was structurally and functionally characterized using UV-Visible spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Nuclear Magnetic Resonance (NMR), and Thermogravimetric Analysis (TGA). Spectroscopic analyses confirmed a glucose-rich heteropolysaccharide backbone with diverse functional groups, exhibiting moderate crystallinity and thermal stability, with major decomposition occurring between 150°C and 330°C. Biological evaluation revealed that the EPS possessed concentration-dependent antioxidant activity, with an IC50 of 0.635mg/mL in the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and 92.5% and 78.3% inhibition for ascorbic acid and EPS, respectively, in the phosphomolybdenum assay. The EPS also exhibited notable anti-inflammatory activity with 72.57% inhibition at 800µg/ml, and broad-spectrum antibacterial activity against Staphylococcus aureus, Klebsiella pneumoniae, Bacillus subtilis, and Escherichia coli, with the highest sensitivity observed in S. aureus. These findings demonstrate the multifunctional bioactivity and biocompatibility of S. yanoikuyae SS02-derived EPS, suggesting its potential as a natural therapeutic agent for pharmaceutical and biomedical applications.

The structures and thermal responses of the calcium uranates α-Ca3UO6 and Ca2UO5 were investigated using in situ synchrotron x-ray diffraction and neutron powder diffraction. Rietveld refinement yielded accurate structural models, with α-Ca3UO6 adopting the rhombohedral R3̅ space group and Ca2UO5 crystallizing in monoclinic P21/c. Thermal behavior was examined using thermogravimetric analysis under varied atmospheres combined with in situ diffraction measurements. α-Ca3UO6 exhibits oxygen loss on heating, manifested as changes in U─O bond lengths within the UO6 octahedra. These changes induce progressive distortion and strain in the CaO6 polyhedra, preceding a distinct structural event observed by synchrotron x-ray diffraction at ∼530°C. Ca2UO5 undergoes two thermally driven events, including oxygen loss at ∼600°C. The presence of trans short U─O (uranyl-like) bonds is considered to play a key role in constraining UO6 octahedral distortion at elevated temperatures. In contrast, the CaOx polyhedra display substantial bond-length variability in response to the rigidity of the U─O framework. At higher temperatures under vacuum, anomalous U─O bond expansion correlates with mass-loss events. These results highlight the complex, environment-dependent thermal behavior of calcium uranates, and the structural significance of short trans U─O bonds.

Abstract The use of CO 2 exposure in hardened cementitious composites can be employed as a treatment to enhance mechanical performance and capture CO 2 in precast elements. Understanding the role of exposure age on the effectiveness of treatment is crucial to leveraging this approach. This study investigates the influence of CO 2 exposure age on the flexural and microstructural development of cement paste. The samples were divided into two groups. One group was exposed to 24-h accelerated CO 2 exposure on 6-day-old specimens, while the other was exposed to 24-h accelerated CO 2 exposure on 27-day-old specimens. Samples of both groups were tested at 28 days for flexural strength, thermogravimetric analysis (TGA), and quantitative X-ray diffraction (XRD). Besides, additional samples were tested at 7 days. The 28-day flexural strength slightly increased (+ 7%) when the CO 2 exposure was performed at 6 days, while it increased 60% with CO 2 exposure at 27 days, with respect to, in both cases, the 28-day flexural strength of unexposed samples. 7-day XRD and TGA results indicate that the samples exposed at 6 days exhibit lower belite content and lower total hydration products than unexposed samples, suggesting a carbonation of belite and a subsequent reduction in hydration due to the early CO 2 exposure. The 28-day results for TGA and XRD of the samples exposed on the 27th day showed similar CaCO 3 content to the samples exposed on the 6th day, but with more hydration products, purer calcite, and greater crystallinity. Late CO 2 exposure yields greater benefits than early exposure on hydration and carbonate formation, providing better flexural performance.

A composite catalytic system composed of choline chloride, p-chlorophenol, and zinc acetate was developed for the efficient glycolysis of waste polyethylene terephthalate (PET). Under optimal conditions (185°C, 4 h, 2.5 wt% catalyst), PET was depolymerized into high-purity bis(2-hydroxyethyl) terephthalate (BHET) with a yield of 96.3%. The catalyst structure was characterized by Fourier-transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance. Key reaction parameters, such as temperature, ethylene glycol/PET ratio, and catalyst loading, were optimized. The obtained BHET was repolymerized by way of melt polycondensation to produce regenerated PET, which exhibited thermal and structural properties comparable with commercial PET, as confirmed by thermogravimetric analysis, differential scanning calorimetry, FTIR, and nuclear magnetic resonance. The catalyst demonstrated excellent reusability, maintaining over 82% BHET yield after six cycles. This study proposes a sustainable, highly efficient, and fully recyclable strategy for closed-loop PET recycling. Specifically, by harnessing a synergistic Lewis–Brønsted acid system, the strategy demonstrates outstanding scalability and thus holds considerable promise for near-term industrial application.

Nowadays, steel has become an important part of our life due to its extensive applications in automotive, household appliances, business machine and heavy construction such as marine and chemical industries. Mild steel is selected for construction because of its mechanical properties and machine-ability at a low price, while at the same time; they have to be resisted against corrosion phenomena. Nano TiO2 can be used for high lubrication‚ high conductivity‚ and high adsorption rate as well as catalytic performance‚ chemical industry‚ aerospace, and other fields. Characterization of this TiO2 are made by X-ray diffraction, Particle size analysis, Scanning electron microscopy, Energy dispersive X-ray spectroscopy, Thermo gravimetric and differential thermal analysis techniques.

Studying the pyrolysis behavior of oil shale provides important guidance for its in-situ or external conversion. The pyrolysis characteristics of Chang 7 sulfur-rich lacustrine shale kerogen were investigated using coupled thermogravimetric analysis, Fourier-transform infrared spectroscopy and mass spectrometry (TG-FTIR-MS) and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) analyses. The TG results revealed four distinct stages: desorption, kerogen conversion, bitumen cracking, and aromatization, with major weight loss occurring between 400 and 600 °C. FTIR and MS analyses indicated that SO2 is generated within 200–700 °C, primarily originating from the decomposition of organic sulfur, while the formation of H2S dominates above 500 °C under a hydrogen radical environment accompanied by substantial hydrocarbon production. Py-GC/MS results showed a temperature-dependent evolution of products from long-chain alkanes to olefins and aromatics, with fatty acids indicating algal-derived kerogen. By integrating real-time gas evolution with temperature-resolved product composition, a multistage pyrolysis mechanism was proposed, demonstrating the coupled evolution of organic matter and sulfur species. This study provides mechanistic insight into the thermal decomposition pathways and differentiated sulfur gas release behavior of sulfur-rich kerogen, which is relevant for understanding sulfur behavior during oil shale thermal conversion.

A study was conducted to examine the effects of graphene nanoplatelets (GNPs) on the thermal characteristics of polymer nanocomposites, which are extensively utilised in packaging, biomedicine, and microelectronics. Following ASTM guidelines, samples of GNPs and epoxy were made by shear mixing and solution compounding. Thermo Gravimetric Analyzer (TGA) and Differential Scanning Calorimetry (DSC) were used to examine the samples' thermal stability and glass transition temperature. The results showed that weight retention improved with increasing graphene content, while the addition of GNPs considerably improved thermal properties. As the GNP content increased from 20% to 30%, the glass transition temperature (Tg) climbed from 50°C to 53°C. This study provides important information for material developers by highlighting the possibility for enhanced thermal performance of graphene-dispersed polymer nanocomposites.

In this study, sol–gel-synthesized nanoparticles were characterized by various physicochemical techniques, including scanning electron microscopy (SEM), X-ray powder diffraction (XRD), UV-Vis spectrophotometry, and thermogravimetric analysis (DTA/TG). The as-obtained powders were tested for their antimicrobial activity against the Gram-positive bacteria Staphylococcus aureus and Enterococcus faecalis, as well as the fungal strains Candida albicans and Saccharomyces cerevisiae. Additionally, the photocatalytic performance of the samples was evaluated under simulated solar light. The results are promising for possible environmental applications. The antimicrobial assessment also revealed notable effects, with varying degrees of growth inhibition observed across the tested microorganisms. The main approach in this study consists of the combination of physicochemical characterization with antibacterial and photocatalytic evaluations, resulting in promising multifunctional materials.

Using montmorillonite (MMT) as raw material, Fe3O4 nanoparticles were loaded on the surface of MMT by a solvothermal method to prepare magnetic montmorillonite (M-MMT). The MMT and M-MMT were functionalized with quaternized chitosan (QC) to obtain nanoparticle (NP) demulsifiers of MMT-QC and M-MMT-QC, respectively. The chemical composition and surface properties of the modified montmorillonite nanoparticles were characterized with scanning electron microscopy, X-ray diffraction, thermogravimetric analysis, zeta potentiometer, and vibrating sample magnetometer, which confirmed the successful preparation of the NP demulsifiers. The demulsification performance of the NP demulsifiers for crude oil-in-water emulsion was evaluated by using bottle tests. The effects of demulsification time, pH, demulsifier dosage, and temperature on the demulsification efficiency were investigated. Results showed that under the condition of 25 °C, 1000 mg/L dosage, and pH 6, the demulsification efficiency of MMT-QC and M-MMT-QC was 98.00% and 98.82%, respectively. In addition, the magnetic NP demulsifier of M-MMT-QC has good recycling performance, with no significant decrease in demulsification efficiency within eight cycles. The demulsification mechanism was revealed and proposed. It is believed that the QC-modified magnetic nanoparticles can firmly combine with the protective film through electrostatic attraction and hydrogen bonds. Under stirring or oscillating conditions, the nanoparticles acquire sufficient kinetic energy to destroy the protective film at the oil-water interface, thereby promoting the oil droplet coalescence and enabling fast oil-water separation at room temperature.

This work focused on the enhanced prediction of methyl orange removal (MO) from water by activated carbon synthesized from banana peels. Characterization was done using powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET). Modeling and prediction of process variables, pH (5-9), time (3-60min), and temperature (25-50°C), was carried out using Box-Behnken design (BBD), artificial neural networks (ANN), and adaptive neuro-fuzzy inference system (ANFIS). Performance metrics of R2, Adjusted R2, Pearson's r, mean squared error (MSE), root mean squared error (RMSE), and mean absolute error (MAE) were used to evaluate the models. The regression coefficients from the modeling and prediction showed that BBD (R2 = 0.9849), ANFIS (R2 = 0.9934), and ANN (R2 = 0.9921), which describes the high prediction capacity of the three models. The performance metrics showed that ANFIS had superior capacity in data modeling and prediction compared to BBD and ANN when analyzing complex non-linear relationships. The Elovich, pseudo-first-order, intraparticle diffusion, and pseudo-second-order kinetic models had high R2 values. The data obtained showed that the pseudo-second-order fitted the data well; as such, chemisorption was the most dominant mechanism. In addition, the isotherm models of Freundlich, Temkin, Langmuir, and Dubinin-Radushkevich were determined. The Freundlich model shows the highest R2, as such adsorption occurs on heterogeneous multilayer surfaces. This study therefore shows the efficiency of ANFIS, ANN, and BBD in the prediction of dye removal by activated carbon synthesized from banana peels.

Reliable quantification of the chemical composition of graphene-related 2D materials (GR2M) as powders and liquid suspensions is a challenging task. Analytical methods such as X-ray photoelectron spectroscopy (XPS), inductively coupled plasma mass spectrometry (ICP-MS), thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FTIR) are recommended by standardization bodies. The specific parameters to be measured are also defined, e.g., the oxygen-to-carbon (O/C) atomic ratio, the trace metal impurities, or the functional groups. In this contribution, for the first time, results of a systematic study on the capability of energy-dispersive X-ray spectroscopy (EDS) at a scanning electron microscope (SEM) to reliably quantify the O/C ratio and impurities remained from the synthesis of selected GR2M are reported. The robustness of SEM/EDS analysis is verified for various measurement conditions (different excitations and EDS detectors) and the validity of the results is tested by comparison to the established XPS analysis. Moreover, an ionic liquid is used as a reference material for the quantification of the light elements such as C, N, O and F. The study clearly demonstrates the reliability of the fast and widely available SEM/EDS as a standard method for the quantification of the elemental composition of GR2M and generally of light materials.