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Using hydrophobic aerogel (AGL) as the carrier, the catalyst supported p-toluene sulfonic acid (p-TSA) is synthesized, and the impact of the hydrophobicity of the catalyst on the formaldehyde–ethylene condensation reaction is investigated. Water contact angle, XRD, N2 adsorption/desorption, IR, and thermogravimetric analysis are used to characterize the catalyst. The outcomes demonstrate the ability of p-TSA to be loaded onto the carrier and the strong hydrophobicity of the catalyst when using AGL as the carrier. The elemental analysis results indicate that when AGL is employed as the carrier, the catalyst not only has more active sites than the SiO2-supported catalyst, but can also effectively limit the loss of active sites, reducing the loss rate from 25.82% to 15.03%. The findings demonstrate that 1,3-dioxane (1,3-DX) had a higher selectivity, rising from 16.2% to 33.3% when using AGL as the carrier. It is discovered that 1,3-propanediol (1,3-PDO) can be directly synthesized with a selectivity of up to 80.5% by employing acetic acid as a solvent in place of water. [ABSTRACT FROM AUTHOR]

Nanostructured ZnNiBi-NO3-Layered Double Hydroxides (LDHs) was synthesised, followed by the simple co-precipitation method using Zn(NO3)2.6 H2O, Ni(NO3)2.6 H2O and Bi(NO3)3 as the precursors. Synthesised LDHs was characterised by various techniques such as infrared (IR) spectroscopy, x-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive x-ray (EDX) and thermal gravimetric analysis (TGA). ZnNiBi-NO3 LDHs were applied as efficient adsorbents for speciation analysis and preconcentration/separation of Cr(VI)/Cr(III) ions in aqueous samples prior to their trace determinations by microsample injection system-coupled flame atomic absorption spectrometry (MIS-FAAS). ZnNiBi-NO3 LDHs worked well for speciation and preconcentration/separation of Cr(VI)/Cr(III) ions at an optimum of pH 3.0 and adsorbent dosage of 400 mg. LOD and LOQ of Cr(VI) ions were calculated to be 0.03 and 0.10 μg L−1, respectively with a preconcentration factor of 400. The total saturation capacity of ZnNiBi-NO3 LDHs for Cr(VI) ions was investigated and found to be 46.0 mg g−1. The mthod was reproduced with RSD ≤1.4% of five replicates. The accuracy of method was evaluated by analysing 10–100 μg L−1 Cr(VI) ions standard solutions, and Cr(VI) ions were recovered ≥96.9% with RSD ≤2.4%. The developed method worked well on wastewater samples. [ABSTRACT FROM AUTHOR]

The TiO2/AC nanosorbent was prepared via the impregnation method. The prepared material was characterised by using X-ray diffraction (XRD), Fourier transform Infra-Red (FT-IR), Thermal gravimetric analysis (TGA) and Scanning electron microscopy (SEM) equipped with energy dispersive X-rays (EDX) to examine crystalline size and structure, purity, morphology, surface area and thermal stability. The prepared TiO2/AC nanosorbent exhibits enhanced surface area and high porosity. The adsorption capacity of the TiO2/AC nanosorbent was evaluated at both laboratory and industrial scales. The effect of contact time, adsorbent dose and heavy metals' initial concentration on the adsorption rate of Pb (II) and Cd (II) were also examined to optimise the adsorption performance of nanosorbent. Under the optimised condition, the percent removal efficiency for Pb (II) and Cd (II) was 91.48 and 93.13, respectively. Different isotherms and kinetic models have been applied to study the adsorption mechanism which suggested that adsorption is exothermic and physical in nature. The maximum adsorption capacity for Pb (II) and Cd (II) obtained by the Langmuir adsorption isotherm was found to be 101.01 and 24.45 mg/g, respectively. Among different kinetic models, Elovich and Weber-Morris intraparticle diffusion fitted well which suggested that the adsorption involves intraparticle diffusion. In addition, the fixed bed column prototype was designed to treat steel industry samples. [ABSTRACT FROM AUTHOR]

The activated carbon (AC) has been widely used in the field of electromagnetic protection because of its porous, hollow microstructure and excellent electrical conductivity. In this paper, AC was prepared through KOH activation process. The ACs/polyimide foam (PIF) composite was prepared in situ during the synthesis of PI and the ACs. In this paper, AC was prepared using the potassium hydroxide (KOH) activation process. The AC/PIF composites were prepared by mixing ACs and pyromellitic dianhydride (PMDA) with methylene diphenyl diisocyanate (MDI). The pore structure and surface morphology of the ACs were observed using nitrogen adsorption–desorption isotherms and scanning electron microscopy (SEM). After KOH activation with KOH, the surface area and total pore volume of ACs significantly increased by 79.31% and 0.9539 cm3/g, respectively, mainly were the microporous structure. X‐ray photoelectron spectroscopy (XPS) results confirmed an increase in the oxygen content of ACs after KOH activation, indicating an increase in the relative hydroxyl content on the surface. The SEM resulting of the ACs/PIF composite has a well‐developed open cell structure. Thermal gravimetric analysis (TGA) revealed that ACs significantly improved the thermal stability of the ACs/PIF composite. The compressive strength of the ACs/PIF‐3 increased from 518 to 834 KPa, significantly enhancing its mechanical properties. Simultaneously, the microwave absorption performance can be controlled and regulated by optimizing the impedance gradient of the skeleton. Results showed that when ACs constituted 8 wt% of the PIF, the real permittivity (ɛ′) and imaginary permittivity (ɛ″) of ACs‐PIF‐5 were approximately 2.03 and 0.025, respectively. [ABSTRACT FROM AUTHOR]

In this study, the performance and potential applicability of polyamide‐12 (PA12) as an alternative to polyamide‐11 (PA11), which is currently used in the coating processes of sliding tools present in cardan shafts, was investigated. The advantages of PA12 powder instead of PA11 in cardan shafts' coating include ease of supply and cost‐effectiveness, while still achieving similar performance. Therefore, PA12 is a more economical choice for coating applications. The PA11 and PA12 neat polymers were characterized via differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA) and dynamic mechanical analysis (DMA). Based on the analyses, PA12 demonstrated substantial advantages over PA11. It showed a 16°C improvement in decomposition temperature and a 50% increase in crystallinity, enhancing stability under operational conditions, whereas PA11 exhibited approximately 6–7% higher values in crystallization and melting temperatures. The wettability behavior of the steel substrates coated with those polyamides was measured via contact angle analysis. Wear properties and morphologies of coatings were examined using a ball‐on disc test and scanning electron microscopy, respectively and comparatively. Furthermore, PA12 typically displays 30% lower wear rates and similar deformation patterns in tests, thereby presenting itself as a cost‐effective and widely accessible option for coating applications in comparison to PA11. [ABSTRACT FROM AUTHOR]

The comprehensive characteristics of an ecologically viable cellulosic fiber from the leaf sheath of Licuala grandis L tree are alkaline modified and investigated in this study. The percentage of cellulose in ideally alkali‐modified Licuala grandis leaf sheath fiber (IALGLSF) increased by 15.8% following a 1 h treatment with a 5% (w/v) alkali buffer. Comparing IALGLSF to raw Licuala grandis leaf sheath fiber (LGLSF), an individual strand tensile testing revealed a 13.2% rise in tensile characteristics. Crystallinity index (CI) analysis using x‐ray diffraction (XRD) showed that IALGLSF had a 12.5% greater CI over LGLSF. Also, Fourier transform infrared spectroscopy (FTIR) experiments validated partial removal of noncrystalline constituents from IALGLSF as a consequence of alkali alteration. Additionally, thermogravimetric (TGA‐DTG) study, which is supported by differential scanning calorimetry (DSC) inquiry, demonstrated that alkali alteration‐enhanced IALGLSF's thermal resistance from 223 to 229°C. Similarly, scanning electron microscopy (SEM) has shown that rougher surface appearance of IALGLSF results from selective removal of noncrystalline constituents, which also provides better matrix contact during reinforcement for the production of eco‐friendly composites. The indicated outcomes validated that IALGLSF serves as a beneficial substitute for potentially harmful synthetic fibers in the production of sustainable biocomposites. [ABSTRACT FROM AUTHOR]

Five varieties of beans from Laibin, Guangxi, China, including mung beans, soybeans, black beans, red beans, and adzuki beans, were chosen as study subjects for multi-index determination and full assessment. Data on the fat, ash, crude fiber, trace element, thermogravimetric analysis and combustion heat of five different types of beans were gathered. The results showed that the order of combustion heat of the 5 kinds of beans was black beans>soybeans>mung beans>adzuki beans>red beans, the order of combustion stability was soybeans>mung beans>black beans>red beans>adzuki beans, the order of fat content was soybeans>red beans>adzuki beans>black beans>mung beans, the order of ash content was black beans>soybeans>adzuki beans>mung beans>red beans, the order of crude fiber content was red beans>soybeans>adzuki beans, and the order of multi-index stoichiometric analysis was soybeans>red beans>black beans>mung beans>adzuki beans. The quality of the food was assessed and classified using the stoichiometric approach, while the food nutrition was assessed from the perspectives of fat, ash, crude fiber, trace elements, thermogravimetric analysis and combustion heat. This work provides a solid scientific foundation for the assessment and investigation of the thermo gravimetric analysis of food combustion stability. This study's multi-index comprehensive evaluation approach offers a novel concept for food nutrition. [ABSTRACT FROM AUTHOR]

Physicochemical profile, phytochemical constituents, bioactivity, and thermal stability of the hydro-distilled essential oil (EO) for T.schimperi and T.serrulatus were investigated. EO yield for T.schimperi and T.serrulatus was 2.05± 0.09% and 1.2 ± 0.3% (w/w) respectively. The chemical profiles of the EO were analyzed using GC-MS (Gas Chromatography-Mass spectrometry).Twenty one (99.99 %) and Twenty (98.59%) EO components were identified from T. schimperi and T.serrulatus, respectively. The two stage mass losses, the first one (38%) was from 37°C to 164°C and (55%) from 46°C to 178°C for T.schimperi and T.serrulatus EO respectively and the second one was (11%) from 164°C to 220°C for T.schimperi and (8%) from 178°C to 223°C for T.Schimperi and T.serrulatus EO respectively were observed for TGA analysis.The essential oils in this study showed a strong antioxidant effect for different tests. IC50 value of 0.17 μg/mL on DPPH assay for both species; 73 ± 0.50 and 64 ± 3.4% inhibition for ABTS assay 4.6 ± 0.42 and 8.04 ± 0.9 mM Fe+2/mL percent in FRAP assay for T.schimperi and T.serrulatus respectively. Antimicrobial activities for both species EOs were investigated on Escherichia coli, Staphylococcus aureus, Salmonella typhi, and Streptococcus epidermidis. MIC values for E.coli and S.typhi were 0.5 and 1 μL/mL for T.schimperi, 2 and 4 μL/mL of T.serrulatus EO, for S.aureus and Streptococcus epidermidis were 0.2 and 4 μL/mL for T.schimperi, 2 and 0.5 μL/mL for T.serrulatus EO's. MBC values for both E.coli and S.typhi were 2 μL/mL for T.schimperi and 4 μL/mL for T.serrulatus EO, While for S.aureus and Streptococcus epidermidis were 1 and 4 μl/ml for T.schimperi, 2 and 8 μL/mL for T.serrulatus EO. [ABSTRACT FROM AUTHOR]

Polycaprolactone/polybutylene adipate terephthalate blends (PCL/PBAT) (90/10, 75/25, and 50/50 wt/wt) containing 1, 3, and 5 phr hydroxyapatite (HA) nanoparticles were prepared using solvent-casting technique. Scanning electron microscopic studies confirmed a homogeneous morphology for the blends and nanocomposites. Some agglomeration can be recognized using energy-dispersive spectroscopy mapping in the blends containing 5 phr HA. The DSC results confirmed the presence of nanoparticles in each phase, particularly in the crystalline region, and wetting coefficient confirmed the localization of nanoparticles at the interface. Thermal stability and degradation kinetics were analyzed using thermogravimetric analysis (TGA). Based on the TGA results, a multi-step degradation process resulted in the blends and blend nanocomposites and the PCL/PBAT blends showed better thermal stability and exhibited higher Tmax and residual mass. PCL/PBAT blends were more stable at higher temperatures compared to PCL and PBAT. Various kinetics evaluation techniques, including Friedman, Flynn–Ozawa–Wall, and Kissinger–Akahira–Sunose methods, were utilized to determine the activation energy of degradation. PCL/PBAT blends were more difficult to thermally degrade and showed the highest degradation activation energy. Incorporating HA led to lower thermal stability and, therefore, lower degradation activation energy. Incorporation of only 5 phr of HA resulted in greater thermal stability at higher temperatures (T90%). [ABSTRACT FROM AUTHOR]

In the 21st century, pathogenic deformities contribute significantly to global morbidity and mortality. Our research investigates the antimalarial, antimicrobial, and antioxidant activities of newly synthesized hydrazones and their organotin (IV) complexes, derived from 2‐benzoyl‐1H‐indene‐1,3(2H)‐dione and 2‐phenoxypropanehydrazide/2‐(2,4‐dichlorophenoxy)propanehydrazide. Structural confirmation was achieved through multinuclear nuclear magnetic resonance (NMR), UV–Vis, IR, HRMS, thermogravimetric analysis (TGA), and scanning electron microscopy (SEM)‐energy‐dispersive X‐ray analysis (EDAX), revealing tridentate coordination of ligands to the tin metal via imine nitrogen and two enolic oxygens, forming a pentacoordinated geometry. The SEM analysis revealed that hydrazone ligand (1) exhibits a rectangular bar‐like microstructure, whereas its complex (5) shows a rugged surface with distinct territorial patches. Compounds (5) [Bu2SnL1] and (6) [Ph2SnL1] stood out with significant bioactivity, with antimalarial IC50 values ranging from 0.54 ± 0.07 to 0.67 ± 0.06 μM and antioxidant IC50 values from 4.39 ± 0.02 to 4.67 ± 0.01 μM. Additionally, compounds (6) [Ph2SnL1] and (10) [Ph2SnL4] exhibited the highest antimicrobial activity, with MIC values ranging from 0.0045 to 0.0042 μmol/mL, respectively, comparable to standard drugs. Complementing the experimental data, in silico molecular docking studies were performed on the most effective ligand (1) [H2L1] and its phenyl complex (6) [Ph2SnL1] with Plasmodium falciparum lactate dehydrogenase, revealing binding energies of −6.0 and −6.9 kcal/mol, respectively, and corroborating the experimental findings. Further, comprehensive absorption, distribution, metabolism, excretion, and toxicity (ADMET) evaluations were performed on each compound to gauge their suitability as drug candidates and potential for toxicity. [ABSTRACT FROM AUTHOR]

The primary aim of this study was to formulate a cake with high antioxidant activity through the incorporation of centrifugally spun gelatin-based fiber which was enriched with caffeic acid. Characterization analyses were conducted to evaluate fibers with different concentrations of caffeic acid (2% and 4%), while simultaneously the effects of thermal and citric acid crosslinking on the physical and functional properties of the encapsulated fibers were investigated. The study revealed varying encapsulation efficiencies of caffeic acid in gelatin fibers (56.34–94.55%), markedly affected by substantial reduction of thermal crosslinking, contrasting with citric acid's minimal impact. Additionally, citric acid increased total phenolic content (TPC), but thermal treatment notably decreased antioxidant activity (AOA) due to its impact on radical scavenging and phenolic group dissociation. The addition of citric acid significantly reduced water vapor permeability by 22% suggesting an induced crosslinking in both thermal-treated caffeic acid and citric acid samples. The study highlighted reduced AOA and phenolic content in thermally treated fibers (thermally treated gelatin with 2% caffeic acid vs thermally treated gelatin with 4% caffeic acid), suggesting lower water solubility and improved thermal stability with approximately 24% remaining weight after thermogravimetric analysis. Despite this, cakes with thermally treated fibers had higher AOA due to improved heat resistance of fibers. Generally, adding fibers to cakes decreased hardness and pH while increasing TPC, AOA, and volume index, showing a novel approach using centrifugally spun fibers to enrich foods with antioxidants. [ABSTRACT FROM AUTHOR]

A stepwise multi-temperature thermogravimetric analysis (SMT-TGA) method is a rapid and time- and material-efficient measurement procedure for oxidation kinetics over a wide range of temperatures. It is suitable for alloy design and material selection procedures. It involves subjecting a sample to a series of steps at increasing temperatures, followed by steps at decreasing temperatures to identify possible effects on the evolution of oxide layer microstructures on oxidation kinetics. This method has been tested for a wide range of metallic alloys in the present work, allowing for the mapping of possible ranges of parabolic oxidation kinetics of industrial alloys between 600 and 1300°C. Two examples of effects of thermal history have also been described in this publication. [ABSTRACT FROM AUTHOR]

This study investigates the thermal degradation kinetics of mesoporous triazine‐based polymers, namely triazine‐amine and triazine‐ether polymers. The synthesis, physicochemical characterization, and catalytic applications of these polymers were discussed in our previous report. Herein, the thermal stability parameters, including kinetic triplets and thermodynamic parameters, were determined using thermogravimetric analysis (TGA) and non‐isothermal mathematical approximations such as Coats‐Redfern, Broido, and Horowitz–Metzger methods. Triazine‐ether polymers exhibit thermal stability within the range of 200°C–300°C, while triazine‐amine polymer demonstrates superior thermal stability, reaching up to 450°C. According to the Coats‐Redfern method, the degradation follows reaction orders of 0.5 ≤ n ≤ 1. The activation energy of triazine‐amine polymer is notably high, particularly at the third degradation stage (e.g., 89.0 kJ/mol by the Broido method), attributed to its high nitrogen content. Conversely, the higher carbon content of triazine‐ether polymers reduces their activation energy to approximately 30 kJ/mol at all stages and thus, facilitates the degradation process. Thermodynamically, the degradation process is favorable yet non‐spontaneous, with intermediate states of the polymers exhibiting higher entropy, indicative of their enhanced degradation capability. [ABSTRACT FROM AUTHOR]

Sodium-rich zeolite A and zeolite X (FAU-type) samples were synthesised from LD-slag via fusion-assisted hydrothermal treatment. The physicochemical and thermal stability of the prepared samples were examined with the help of various characterisation techniques, namely, Fourier Transform Infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and thermogravimetric analysis (TGA) analysis at three different pH conditions and treatment time. Moreover, the sustainability of the crystalline phase and the corresponding zeolite network was evaluated from XRD, FTIR, TGA and Field-Emission Scanning Electron Microscopy (FESEM) analysis. Zeolite A depicts a unique cubical structure and is thermally more stable as compared to zeolite type-X. Also, zeolite A showed the highest dye removal efficiency of 98.13%, as compared to 94.47% for zeolite X, along with equilibrium sorption capacities of 25.30 and 23.57 mg g−1, respectively. In addition, the study proposes that both the synthesised adsorbents are effective and economically sustainable for cationic methylene blue adsorption. Furthermore, methylene blue adsorption was regulated by a multistage diffusion process that agreed with a pseudo-second-order kinetic model (R2 = 0.999 and 0.996 for A- and X-type zeolites). The Langmuir isotherm model best suited the equilibrium data, with monolayer adsorption capacities of 20 and 25.40 mg g−1, respectively. [ABSTRACT FROM AUTHOR]

The results of thermogravimetric analysis of polyacrylonitrile fiber samples after the process of oxidative thermal stabilization in air are presented. Based on a study of a commercial sample of PAN fiber, the dependences of the weight loss of the starting material on the final temperature of oxidative thermal stabilization and the heating rate are presented. A machine learning model was built using the results of the experiments in order to predict the dependence of the weight loss of the starting material on the technological parameters of the oxidative thermal stabilization process. [ABSTRACT FROM AUTHOR]

Biomass utilization has attracted great attention for decades, and the dried distiller's grains with solubles (DDGs) is an important source which is the by-product of brewing industries, as fermented from raw biomass such as rice, wheat and sorghum. Currently, there are a few studies on the kinetics and thermodynamics of distiller's grains biomass. Therefore, the physicochemical characterization, kinetic and thermodynamic analyses of DDGs and DDGs-biochar were studied. The characterization results confirmed that DDGs had high volatile matter (81.6%) and higher heating value (21.3 MJ kg−1). The pyrolysis kinetics of DDGs and DDGs-biochar at four heating rates of 5, 10, 20 and 40 K min−1 were investigated by non-isothermal thermogravimetric analysis. The isoconversional method such as Kissinger-Akahira-Sunose (KAS), analysis showed that the effective activation energy varied with the change in the conversion rates. For DDGs, it was 122–159 kJ mol−1 (α: 0.1–0.2), 160 ± 6.20 kJ mol−1 (α: 0.20–0.75) and 179–194 kJ mol−1 (α > 0.75), corresponded to thermal decomposition of hemicellulose, cellulose and part of lignin, and remaining lignin respectively; as to combustion of DDGs-biochar, it was 152 to 60.1 kJ mol−1 (α: 0.1–0.9) indicated that some of the more complicated structures in DDGs had been carbonized, making as-obtained biochar easier to burn owing to the lower activation energy. The changes in enthalpy, Gibbs free energy and entropy of DDGs and DDGs-biochar were calculated, and the results were helpful to evaluate the conversion efficiency and technical feasibility of DDGs pyrolysis and DDGs-biochar combustion processes. [ABSTRACT FROM AUTHOR]

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Wood-polymer hybrids demonstrate unique perspectives in green architecture, energy-efficiency building, optoelectronics, photovoltaic devices, and energy storage materials. The fabrication of wood-polymer hybrids preliminary involves the acquisition of delignified wood templates. In this framework, the potentiality of species diffused in the Mediterranean area is nearly unexplored. For such purpose, four hardwoods (Beech, European Hop Hornbeam, Turkey Oak and Paulownia) and one softwood (Corsican Pine) have been selected on the basis of their anatomical features, density, and potential exploitation of natural resources. The goal is to evaluate and compare the properties of delignified woods derived from the selected species for the fabrication of wood-polymer hybrids, including transparent wood products. Wood samples of different cut (longitudinal or transversal) and thickness (1 mm or 3 mm) were soaked in an alkaline sulfite solution and mildly bleached in hydrogen peroxide. Dry mass loss was determined in different experimental conditions. Macro- and microstructure of delignified woods have been investigated by optical microscopy, scanning electron microscopy, infrared spectroscopy and X-ray diffraction analysis. Thermal degradation profiles were acquired by thermogravimetry, the total transmittance measured in the UV–Vis range and mechanical properties evaluated by tensile tests. The dry mass loss ranged within 26–52%. Delignified hardwoods showed enhanced optical transmittance especially Paulownia (+ 80%) and Turkey Oak (+ 140%), characterized by large vessels and thin cell walls, while the macro- and mesostructure along with tensile properties were preserved. These cellulose-rich wood templates deserve to be further considered for the fabrication of wood-polymer hybrids and particularly transparent wood products. [ABSTRACT FROM AUTHOR]

Cellulose acetate (CA) has been extensively studied with minimal regard to end-of-life analysis. Cigarette filters predominantly comprise CA fibers and chemical additives for filtration and manufacturing, altering their physicochemical and thermal properties and influencing their interactions with the environment upon disposal. This research established and employed multifaceted analyses to determine the physicochemical and thermal properties of cellulose acetate sourced from unsmoked cigarette filters and pristine CA powder, including Fourier transform infrared spectroscopy (FTIR), optical and electron microscopy, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). FTIR analysis ascertained the structure of CA by resolving spectral peaks while pointing out the effects of additives, processing conditions, and the degree of substitution. An increase in the latter indicates reduced biodegradability and potentially longer persistence after disposal. The morphology was examined using electron and optical microscopies, revealing insights into FTIR results. TGA elucidated the decomposition response, evidencing moisture and volatile retention in the CA fibers extracted from unsmoked cigarette filters, suggesting unique decomposition behavior due to the reactivity of the additives with the surrounding environment. The thermal decomposition of unsmoked cigarette filters is insensitive to inter- and intra-filter variability. DSC analysis identified the thermal transitions of the CA fibers and powder, accentuating the effects of morphology, entanglements, and plasticizers on the structural stability of cellulose acetate. Our research establishes a baseline characterization of cigarette filters, laying the scientific foundations for further investigations into this pervasive pollutant. [ABSTRACT FROM AUTHOR]

Recently, direct methanol fuel cells (DMFCs) have been regarded as the greatest energy-producing owing to their low operating temperature, high production rate of methanol, and low greenhouse gas emission. However, the energy conversion efficiency of the DMFCs is still unsatisfactory due to the slow kinetics of the fuel oxidation reaction. So, an economic electrocatalyst with high efficiency and good stability is still needed. Herein, low-cost nanocomposites of (Ni/Cu/N) MOF and palm pollen-derived G-graphite were prepared with different ratios namely, (1:1), (1:2), and (2:1) through a solvothermal reaction. The nanocomposites were characterized via X-ray diffraction (XRD), Scanning electron Microscopy (SEM), Fourier transform infrared (FTIR), Thermal gravimetric analysis (TGA), and, (Brunauer–Emmett–Teller) technique (BET). Electrodes have been tested as electro-catalysts for methanol-oxidation reaction (MOR) in a basic medium. As revealed from the cyclic voltammetry measurements, all electrodes exhibit a good response to MOR, being the nanocomposite with the ratio between (Ni/Cu/N) MOF and G-graphite (2:1) is the best with an oxidation peak current density of 55 mA/cm2 at a scan rate of 50 mV/s, with an onset potential of 0.35 V, and stability reaches 96 %. The electrochemical impedance spectroscopy (EIS) test showed that the ratio (2:1) has the lowest charge transfer resistance, R CT , of 5.21 Ω which confirms its higher electrochemical activity. This superior performance of the (Ni/Cu/N) MOF and G-graphite (2:1) over other reported MOF-based electrocatalysts is attributed to the synergistic effect of the (Ni/Cu/N) MOF electrocatalyst, wherein Ni and Cu provide redox electrocatalytic active sites for MOR while the G-graphite contributes towards the chemical stability and electrical conductivity of the electrode, respectively. The good activity and stability of the prepared electrodes suggest the potential use of these electrodes as electrocatalysts for MOR in direct methanol fuel cells (DMFCs).This study opens the venue for valorizing the natural wastes derived graphitic material as stable supporting material in Mof based composites electrodes for MOR. • Green Graphite derived from palm pollen grains was prepared simply. • low-cost nanocomposites of (Ni/Cu/N) MOF pollen-derived G-graphite were prepared. • (Ni/Cu/N) MOF- based nanocomposites prepared with different ratios. • The prepared materials were tested as electro-catalysts for MOR. • Nanocomposite of (Ni/Cu/N) MOF and G-graphite with a ratio (2:1) display superior performance. [ABSTRACT FROM AUTHOR]

This study investigates the synthesis of zinc-based metal–organic frameworks (MOFs) using tetrahydrofuran (THF) as a solvent, focusing on forming distinct phases as models for potential battery applications. Contrary to expectations, the synthesis produced three unique phases: alpha, beta, and Zn-MOF-74a, instead of the anticipated Zn-MOF-74 structure. Comprehensive structural analysis using X-ray diffraction, infrared spectroscopy, and thermogravimetric analysis (TGA) revealed distinct crystallographic features for each phase, particularly the novel Zn-MOF-74a phase, which exhibits a heart-shaped pore structure and differs from the classic hexagonal MOF-74. The study also includes the first structural determination of the dry H4DOBDC precursor, providing crucial insights for future research. The results demonstrate the significant impact of solvent choice, temperature, and pH on MOF phase formation and offer potential applications in energy storage and catalysis, especially for larger molecules. Further investigation is required to fully understand the electrochemical properties and phase stability of the newly identified Zn-MOF-74a and beta phases. [ABSTRACT FROM AUTHOR]

A series of imidazolium gemini surfactants with three different hydrophobic chains have been synthesised and analysed by 1HNMR, 13CNMR, FTIR, ESI-MS and TGA. The conductivity of these surfactants has been taken at 293, 298, 303 and 308 K in water, and results have indicated that these gemini surfactants act as weak electrolytes. Thermodynamic properties calculated from conductance have confirmed that micellization was spontaneous and more favourable in comparison to dissociation process. Density as well as viscosity measurements were indicating that there exist significant interactions between these gemini surfactants and solvent (water) molecules. Surface active properties have confirmed that imidazolium gemini surfactants are excellent candidates to lower the surface tension at air/water interface and having affinity to form aggregates in the bulk solution after CMC. Thermogravimetric analysis (TGA) has indicated that all the three surfactants have thermal stability up to 535–600 °C. The thermal stability was increasing with increasing hydrophobic chain, and the activation energy for thermal decomposition was found in the range of 20.43–36.55 kJ/mol. Moreover, antimicrobial activities were examined and inferred that these compounds exhibit excellent antimicrobial activity against B. cereus and C. albicans. [ABSTRACT FROM AUTHOR]

The novel perovskite Sr 0.90 Ba 0.10 Co 0.95 Ti 0.05 O 3-δ has been designed as cathode material to be used in intermediate-temperature solid oxide fuel cells (IT-SOFC). To enlarge the unit-cell size and enhance oxygen diffusion, Sr atoms have been partially substituted by a 10 % of Ba. This new compound was characterized through X Ray Diffraction (XRD) unveiling a tetragonal phase at RT. An in situ Neutron Powder Diffraction (NPD) study between RT and 800 °C showed a transition to a cubic perovskite at 400 °C, which was also noticeable in the thermogravimetric analysis (TGA) and dilatometric analysis. Adequate chemical and mechanical compatibility were achieved with the components of the cell. Electrical conductivity peaked at 400 °C, with values over 200 S cm−1 , where it changed its behavior from semiconductor-like to insulator. Finally, polarization resistances as low as 0.062 Ω cm−2 were obtained for the working temperature of the cell in a symmetric cell, associated with the excellent power densities of 564 and 752 mW cm−2 obtained at 850 °C using pure H 2 as fuel for the conventional test fuel cell and in a Pd-infiltrated one. [ABSTRACT FROM AUTHOR]

This study probes two solvates of triphenylamine (TPA) bis-urea macrocycle 1 and their activated structures to evaluate their maximum photoinduced radicals (PIRs), the subsequent decay of the radicals, and their regeneration. The hierarchical assembly of TPAs shows promise in stabilizing less substituted derivatives, potentially expanding the utility of TPAs that lack stabilizing para-substituents. Single crystal structure analysis reveals that host 1 adopts a planar conformation with the two ureas pointing in opposite directions when dimethoxyethane (DME) is encapsulated within the channel. Whereas previously, 1 adopted a bowl-shaped conformation with the two ureas pointing in the same direction (syn) with dimethylsulfoxide (DMSO) bound within the channels. Removal of the guests gives identical activated structures. The bulk materials of 1 are characterized by powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). Finally, the process of radical generation under UV-irradiation, decay, and regeneration of radicals was monitored by electron paramagnetic resonance (EPR) spectroscopy. While macrocycle conformation and extended structure are important, the presence of guests was most significant for PIR percentages. [ABSTRACT FROM AUTHOR]

Magnetic superabsorbents have been successfully synthesized through aqueous solution polymerization, employing sodium alginate as the backbone material, acrylic acid and acrylamide as the polymeric monomers, Fe3O4 nano-particles as the magnetic component, N,N'-methylenebisacrylamide as the crosslinking agent, and ammonium persulfate serving as the initiator. The micro-morphology and thermal stability of these superabsorbents were thoroughly characterized using scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA), respectively. A comprehensive investigation was undertaken to examine the swelling capacity, water retention properties, magnetic responsiveness, and reusability of the magnetic superabsorbents. The findings reveal that these superabsorbents possess an impressive maximum water absorption capacity of 302.7 g/g in distilled water. Notably, their swelling ratios maintain high levels within a pH range of 5–10. Featuring a porous structure, the magnetic superabsorbents demonstrate rapid swelling kinetics, attaining swelling equilibrium within 30 min in a 1 wt% NaCl solution. Furthermore, the superabsorbents exhibit excellent magnetic responsiveness, characterized by a maximum saturation magnetization of 7.91 emu/g, allowing for swift separation under an external magnetic field. Lastly, the magnetic superabsorbents display outstanding reusability, with their water absorption capacity in distilled water still exceeding 90% of the initial swelling ratio after seven reuse cycles. [ABSTRACT FROM AUTHOR]

AbstractHexachlorocyclotriphosphazene (HCCP) was reacted with piperazine to obtain poly(cyclotriphosphazene-co-piperazine) particle (PCPS), which was used as the flame retardant for epoxy resin (EP). The structure of PCPS was determined by various methods. When PCPS was used alone and the addition amount of PCPS in the prepared flame-retardant EP (FR-EP) reached 4%, the obtained FR-EP cannot even pass the V-1 level in the Vertical burning (UL-94) test. However, PCPS showed a synergistic flame retardancy with aluminum diethylphosphinate (ADP). When the mixture of ADP and PCPS in EP was 4% and the weight ratio of ADP and PCPS was 3:1, the prepared FR-EP, EP-ADP/PCPS3:1, reached the V-0 level in the UL-94 test. The limiting oxygen index (LOI) value of EP-ADP/PCPS3:1 was 29.7%. Compared with pure EP, the peak heat release rate of EP-ADP/PCPS3:1 obtained by the micro-combustion calorimetry (MCC) test was reduced by 20.6%. Thermogravimetric analysis (TGA) result showed that, with the addition of ADP and PCPS, the char residual of EP-ADP/PCPS3:1 increased about 5.1% compared with EP. The combination of ADP and PCPS showed significant advantage in promoting the flame retardancy of EP. Compared with pure EP, the mechanical properties of EP-ADP/PCPS3:1 was hardly decreased with the addition of ADP and PCPS. [ABSTRACT FROM AUTHOR]

In this work, the comparison between nitrogen and air synthesis environments in obtaining In0.6Ga0.4N powders is presented, and the effect of how the air environment can reduce the pyrolysis temperature of In0.6Ga0.4N powders to 271 °C using the thermal gravimetric analysis, and derivative thermogravimetry methods. X‐ray diffraction patterns demonstrate the presence of a cubic phase in nanocrystallites, in addition to less presence of the hexagonal phase. In contrast, scanning electron microscopy micrographs show a surface morphology of irregular agglomerates with a porous appearance and the presence of nonuniform plates. Energy‐dispersive spectroscopy and X‐ray photoelectron spectroscopy spectra demonstrate the presence of elemental contributions of gallium, indium, and nitrogen. At the same time, transmission electron microscopy shows the cubic structure and an interplanar distance of 2.7 Å for the (200) plane. Raman scattering shows the presence of E2(high) vibration mode for the hexagonal phase with a value of 560 cm−1. Finally, the photoluminescence spectrum shows an energy emission at 1.39 eV (886 nm), which is associated with the emission of the In0.6Ga0.4N powders. [ABSTRACT FROM AUTHOR]

Magnetic superabsorbents have been successfully synthesized through aqueous solution polymerization, employing sodium alginate as the backbone material, acrylic acid and acrylamide as the polymeric monomers, Fe3O4 nano-particles as the magnetic component, N,N'-methylenebisacrylamide as the crosslinking agent, and ammonium persulfate serving as the initiator. The micro-morphology and thermal stability of these superabsorbents were thoroughly characterized using scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA), respectively. A comprehensive investigation was undertaken to examine the swelling capacity, water retention properties, magnetic responsiveness, and reusability of the magnetic superabsorbents. The findings reveal that these superabsorbents possess an impressive maximum water absorption capacity of 302.7 g/g in distilled water. Notably, their swelling ratios maintain high levels within a pH range of 5–10. Featuring a porous structure, the magnetic superabsorbents demonstrate rapid swelling kinetics, attaining swelling equilibrium within 30 min in a 1 wt% NaCl solution. Furthermore, the superabsorbents exhibit excellent magnetic responsiveness, characterized by a maximum saturation magnetization of 7.91 emu/g, allowing for swift separation under an external magnetic field. Lastly, the magnetic superabsorbents display outstanding reusability, with their water absorption capacity in distilled water still exceeding 90% of the initial swelling ratio after seven reuse cycles. [ABSTRACT FROM AUTHOR]

This study investigates the capabilities of various measurement techniques for quantifying the cellulose content in reject material from a carton recycling center, which consists of polyethylene, cellulose, and aluminum, along with impurities. Different measurement techniques, including Fourier Transform Infrared Spectroscopy combined with Attenuated Total Reflectance (FTIR-ATR), cellulose dissolution using cupri-ethylenediamine (CED) from plastic followed by gravimetric analysis, acid hydrolysis combined with chromatography, and Thermal Gravimetric Analysis TGA, are employed in this study. Acid hydrolysis combined with chromatography and TGA shows comparable results when compared to different techniques for analyzing pulper reject. Dissolution with CED showed also comparable results but shows higher variation than TGA or chromatography. FTIR absorbance ratio of 1025/2917 correlates with cellulose content, but it shows high variation and lacks sensitivity below 5% cellulose content in polyethylene. This limitation is attributed to factors such as the limited measurement area (1.8 mm) and the large particle size of the cellulose and LDPE mixtures, possibly caused by inadequate grinding of LDPE. In conclusion, TGA and acid hydrolysis combined with chromatography are the most reliable for quantifying cellulose content in recycling reject, providing more consistent and accurate results than FTIR-ATR or CED dissolution methods. [ABSTRACT FROM AUTHOR]

In this study, poly(lactic acid)‐poly(ethylene glycol)‐tetra‐n‐butylammonium hydrogen sulfate (PLA‐PEG‐HS) electrospun mats were fabricated by electrospinning as effective wound dressings against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), which are the most prevalent species of gram‐positive and gram‐negative bacteria, respectively. PLA is a polymer with high biocompatibility and biodegradability, but its structure is fragile. Therefore, we aimed to improve its structural properties using PEG as a plasticizer and to provide antibacterial properties with HS salt. The nanofibers characterized using differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectroscopy, thermal gravimetric analysis (TGA), and drying time tests. The addition of HS eliminated the beads in the PLA‐PEG nanofiber and improved the homogeneity of the fiber distribution. Concerning this result, when the liquid absorption capacity (LAC) test was evaluated, PLA‐PEG‐HS nanofiber production was achieved with the highest rate of 480.95%. The thermal properties of nanofibers increased with the addition of HS. Cytotoxicity test results of PLA‐PEG‐HS wound dressings showed high cell viability of 129.05% in L292 mouse fibroblast cells at the end of the 24th hour. PLA‐PEG‐HS nanofibers with 99.99% antibacterial activity against tow bacteria. Considering the modern wound dressing requirements, antibacterial wound dressing production has been successfully achieved. [ABSTRACT FROM AUTHOR]

Carbon particles (CP) with functional groups are one of the promising modifiers for polymer matrices to create pervaporation mixed matrix membranes (MMM) with tailored properties. In this context, a detailed study of the effect of polymer modification with various CP is required. Thus, in this study, highly efficient MMM based on chitosan (CS) for enhanced pervaporation dehydration of isopropanol were developed by modification with graphene oxide, fullerenol, carboxyfullerene, single- and multi-walled (MWCNT) nanotubes. The effect of CP introducing into the CS matrix was investigated, where the CS/MWCNT composite demonstrated optimal transport properties as a dense membrane material. To increase efficiency, an optimal cross-linking agent for improvement of the membrane stability in an aqueous media was selected, and supported membranes from CS/MWCNT composite were developed. The structural changes during modifications were investigated by spectroscopic (FTIR and NMR) and microscopic (SEM and AFM) methods. Physicochemical properties of MMM were studied by thermogravimetric analysis, measurements of contact angles and swelling degree. The optimal cross-linked supported membrane with a thin dense layer from CS/MWCNT (5%) composite had in 2–4 times increased permeation flux and higher water content in the permeate (99.9–98.5 wt.%) compared to the pristine dense CS membrane in pervaporation dehydration of isopropanol (12–50 wt.% water). This membrane also demonstrated high stability in separation till 90 wt.% water in the feed with the following transport parameters of 1 kg/(m2h) and 97.5 wt.% water in the permeate. [ABSTRACT FROM AUTHOR]

The application of polymer blends such as epoxidized natural rubber (ENR) and polyvinyl chloride (PVC) in immobilizing titanium dioxide (TiO2) photocatalysts has enticed many researchers. However, the presence of polymer limits the photocatalytic activity by hindering the surface‐active site of the immobilized TiO2. In this study, photoetching treatment with the presence of dye was successfully applied on the immobilized TiO2/ENR/PVC (TEP) to enhance the photocatalytic and photoelectrochemical (PEC) performance. Priorly, a dip coating technique was used to immobilize the TEP. The dye photoetching treatment was performed for several cycles to determine the reusability of the immobilized TEP. Furthermore, it demonstrated a significant enhancement of photocatalytic activity at which the best performance with the pseudo‐first‐order rate constant, k value of 0.1483 min−1 at the 13th cycle. The nonetched, photoetched TEP without dye and dye photoetched TEP have been characterized by scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET), X‐ray diffraction (XRD), thermal gravimetric analysis (TGA), and PEC. It is believed that the dye photoetched TEP will produce a good photocatalytic activity and PEC performance due to the presence of dye stimulant during the photoetching treatment. [ABSTRACT FROM AUTHOR]

Gene delivery has emerged as a novel and effective method in the treatment of malignancies within medical interventions by applying nanotechnology. Consequently, the development of appropriate nanocarriers is a key focus of this research. Dynamic light scattering (DLS), fourier transform infrared (FT-IR) spectroscopy, x-ray diffraction (XRD), and thermal gravimetric analysis (TGA) were employed for the characterization of the synthesized nanocarrier. Furthermore, to assess the gene transfer capability of the nanocarrier, various techniques such as gel retardation assay, nuclease resistance assay, cytotoxicity assay, flow cytometry, and transfection were employed. The average particle size and zeta potential of the GO-CS@Ca nanocarrier were obtained as 319.8 nm and + 92.8 mv, respectively. In the gel retardation test, it was observed that pDNA was effectively condensed by the GO-CS@Ca nanocarrier. The results of the MTT assay indicated that both GO-CS@Ca nanocarrier and the GO-CS@Ca/pDNA nanoplex with low toxicity. In flow cytometry analysis, it was observed that the complexation of pDNA with the GO-CS@Ca nanocarrier resulted in effective gene delivery to the MCF-7 cell line and consequently increased apoptosis induction. [ABSTRACT FROM AUTHOR]

Chicken eggshells (ESs) consist of 96%–97% calcium carbonate, while about 3%–4% consists of organic substances, mainly in the form of protein‐based membranes and occluded organic matter. Recently, ESs have been studied as a filler in polymer composite materials, which represents an innovative solution to address ES valorization. In this study, thermal and chemical treatments were investigated for membrane removal since the membrane may alter various properties when the ES fillers are added to the composite material. A nanoindentation method was used to measure changes in the ES mechanical properties. Scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and Fourier‐transform infrared (FT‐IR) spectroscopy were used to characterize the ES membrane removal through chemical treatment. The results showed that even at a heating temperature of 100°C, the ES mechanical properties were negatively affected, while a low concentration of bleach solution (25% bleach solution and 10 min of holding time) was able to remove the membrane without reducing the ES mechanical properties. The chemical treatment method offers a means for ES membrane removal while conserving the quality of the mineral fraction (calcite; CaCO3). [ABSTRACT FROM AUTHOR]

The physiochemical pretreatment was performed using different concentrations of oxalic acid (OA) as a simultaneous pretreatment and saccharification (SPS) process on rice straw to obtain reducing sugar from two‐phasic SPS process using enzymatic and acidic hydrolysis to subsequently ferment to bioethanol in order to maximize the yield of bioethanol. The optimal condition for pretreating rice straw using 0.5, 0.75, 1, and 1.5 M OA at 120°C for 1 h was evaluated. The morphological and structural changes after simultaneous pretreatment and SPS process were evaluated using Fourier‐transform infrared (FTIR), thermogravimetric analysis (TGA), X‐ray diffraction (XRD), and field‐emission scanning electron microscopy (FESEM) analysis. It was evaluated that optimum pretreatment conditions using a lesser concentration of OA had resulted in 30.37% of xylan removal from pretreated rice straw obtained after simultaneous pretreatment and SPS process. The ethanol production yield ranged from 0.42 to 0.37 g/g with fermentation efficiency of up to 57.18% and an overall ethanol production yield of 42.84% from the obtained hydrolysate of the two‐phasic SPS process. The highest ethanol concentration from the obtained hydrolysate was produced at 120°C for 1 h with 0.75 M OA; under this condition, maximum degradation of utilized lignocellulosic biomass takes place. [ABSTRACT FROM AUTHOR]

Six varieties of alkoxy polyhedral oligomeric silsesquioxanes (POSSs) featuring methoxy, ethoxy, n‐propoxy, isopropoxy, n‐butoxy, and n‐hexoxy as terminal groups were synthesized using the direct dehydrogenation condensation method. These POSSs were then incorporated as cross‐linking agents into hydroxy‐terminated polydimethylsiloxane (HPDMS) to create various formulations of room temperature vulcanized silicone rubbers (RTV SRs), denoted as SRM, SRE, SRP, SRI, SRB, and SRH. The morphology, thermal stability, and mechanical properties of the resulting SRs are analyzed using scanning electron microscopy (SEM), thermal gravimetric analysis (TGA) and universal tensile testing machine. The findings indicate that the incorporation of POSS into SRs results in significant enhancements in thermal stability and mechanical properties when compared to the control group (TEOS/SR). SRB and SRH exhibit the highest cross‐linking density and tensile strength. Specifically, SRB‐4 demonstrates the highest tensile strength at 2.66 MPa, representing an 8.6‐fold increase compared to TEOS/SR. The maximum decomposition rate temperature of SRP‐4 reaches 527°C and is 194°C higher than TEOS/SR. Because the alkoxy groups with different chain lengths on POSS have different chemical reactivity, they have a great effect on the dispersion of POSS in SRs, which affect the cross‐linking density, tensile strength, and thermal stability. [ABSTRACT FROM AUTHOR]

The high energy consumption of Carbon Capture Utilization and Storage(CCUS) promotes the research of integrated absorption and mineralization technology. A novel DEEA/AEP biphasic absorbent is used to absorb . After phase separation, only one phase enriched with the absorption product is sent into the mineralization system, then reacts with to produce at normal temperature and pressure. The effects of temperature, Ca/C and dispersion of the system were investigated, and cyclic utilization experiment was also conducted. The process was characterized and analyzed by Thermal gravimetric analysis (TGA), X-ray diffraction (XRD), and nuclear magnetic resonance (13C NMR). The results showed that at 50 C, Ca/C = 1, the extent of mineralization of -enriched phase mineralization was 95.73% after ultrasonic treatment for 30 min. During 6 cycles, the volume percentage of -enriched phase could be maintained at 52–55%, and the load was 11.92mol/L. The results above indicate that the -enriched phase mineralization technology after absorption by biphasic absorbent can effectively capture , realize recycling, and reduce CCUS energy consumption. [ABSTRACT FROM AUTHOR]

This study investigates the impact of acetylation treatment on Enterolobium cyclocarpum (Parota) starch, focusing Morphological, Physico‐chemical and thermal impact induced by varying acetylation levels. The research employed scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA) to examine the structural and thermal alterations resulting from acetylation. These analyses also evaluated the starch's thermal stability. Through titration, the degree of substitution and acetyl group content were quantified, demonstrating significant morphological transformations in the starch, such as increased particle size and the appearance of surface cracks on the granules. The study revealed that the degree of substitution, which changes with the duration of acetylation, markedly influences the starch's physicochemical properties, including hydrophobicity and thermal stability. Initially, acetylation reduced the gelatinization temperature, suggesting a decrease in the energy required for gelatinization. Over longer acetylation periods, however, the gelatinization temperature increased, likely due to enhanced crystallinity or molecular reorganization. These findings indicate that acetylated Parota starch has potential applications in the food industry as an encapsulating agent and in the thermoplastics industry as a plasticizer, dependent on the level of acetylation. This research underscores the utility of specific chemical modifications to adapt starch properties for various industrial applications. [ABSTRACT FROM AUTHOR]

In this study, the synthesis and characterization of the fluorescent metal–organic framework (MOF)‐polymer composites is reported based on zirconium‐based MOFs (UiO‐66 and UiO‐66(OH)₂) and a conjugated polyelectrolyte, poly(phenylene ethynylene) carboxylate (PPE‐CO₂‐108). The defect‐rich nature of these Zr‐MOFs facilitates strong interactions between the polyelectrolyte's carboxylic acid moieties and the open metal sites on the Zr clusters within the MOF nanoparticles. The composites are prepared by a simple impregnation approach, where MOF nanocrystals suspended in HEPES buffer are added to the polymeric solution under sonication for 10 min. The obtained MOF composites (i.e., UiO‐66‐CPE and UiO‐66 (OH)2‐CPE) are characterized using powder X‐ray diffraction (PXRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), Brunauer‐Emmett‐Teller (BET) surface area, zeta potential measurements, and UV–vis spectroscopy. The characterization confirmed the homogeneous distribution of the MOF nanocrystals on the polymer as seen in the SEM images, and the interaction with PPE‐CO₂‐108 is confirmed by the decrease in the surface areas from 1050 to 590 m2 g−1 for UiO‐66‐CPE and from 500 to 137 m2 g−1, for UiO‐66(OH)2‐CPE. Fluorescence microscopy revealed strong fluorescence in the microparticles, confirming robust polymer‐MOF interaction. The composites also exhibit improved photostability of the conjugated polyelectrolyte, suggesting their potential for applications in biomedical imaging and other areas requiring stable and bright fluorescent systems. [ABSTRACT FROM AUTHOR]

Thrombin was immobilized on magnetic core‐shell mesoporous silica nanoparticles (Fe3O4@nSiO2@mSiO2) for the first time and used to screen enzyme inhibitors from extracts of Notopterygium incisum. The immobilized thrombin was characterized by Fourier‐transform infrared spectroscopy, transmission electronic microscopy, thermal gravimetric analysis, and vibrating sample magnetometry. The results demonstrated that the immobilized thrombin possessed good thermal stability and high‐temperature resistance for feasible storage and reuse. Two ligands, notopterol (1) and isoimperatorin (2) were fished out from the extract of N. incisum using the immobilized thrombin. They inhibited thrombin with IC50 values of 59.35 ± 1.420 and 107.8 ± 1.660 µM, respectively. This is the first report of thrombin‐inhibitory activity associated with notopterol and isoimperatorin. Meanwhile, the inhibition mechanism of both compounds was investigated by enzyme kinetic analysis and molecular docking. The method used enables rapid screening for thrombin inhibitors from medicinal plants, providing an efficient tool for the discovery of anti‐thrombotic active compounds. [ABSTRACT FROM AUTHOR]

In the current study, we attempt to remove 3‐monochloropropane‐1,2‐diol fatty acid ester (3‐MCPD ester) from palm oil with developed composite adsorbent (Tween80 modified activated carbon [AC]), and scanning electron microscopy‐energy dispersive spectrometer, Fourier transform‐infrared spectroscopy, X‐ray diffraction, nitrogen content adsorption‐desorption and thermogravimetric analysis were used to characterize the modifications. We further examined the adsorption capability of the composite adsorbent for 3‐MCPD ester and found that the highest removal efficiency was 87.36% (5.3% of adsorbent dose at 104°C for 29 min). This is approximately three times higher than that of pristine AC, implying that the composite can be employed as a novel adsorbent for 3‐MCPD ester reduction. Along with the adsorption mechanism of Langmuir, Freundlich, Dubinin–Radushkevich, and Temkin models were also tested. It has been suggested that Freundlich model could best describe the adsorption process. Adsorption was found to be well‐fitted by pseudo‐second‐order kinetics according to the kinetic study. An endothermic and spontaneous adsorption mechanism was demonstrated by the thermodynamic studies. [ABSTRACT FROM AUTHOR]

Oligomeric poly(α-methyl-β-alanine)with vinyl end-group (PmBA) was synthesized via base-catalyzed hydrogen-transfer polymerization (HTP) of molten methacrylamide (MAm) in the presence of sodium tert-butoxide (t-BuONa). The PmBA was used as a comonomer in the synthesis of amphiphilic poly(2-hydroxyethyl acrylate-g-α-methyl-β-alanine) (PHEA-g-PmBA)via nitroxide-mediated polymerization (NMP)and "grafting through" approach.The graft copolymer formation was confirmed byproton nuclear magnetic resonancespectroscopy (1H-NMR), Fourier-transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and static light scattering (SLS)measurements. Thermogravimetric analysis of the amphiphilicPHEA-g-PmBAexhibited a multi-step decomposition curve corresponding to the α-methyl-β-alanine and the 2-hydroxyethyl acrylate blocks at about 306, 369, and 403 °C.DSC curve of the copolymer has a baseline shift at −12.87 °C attributed to the glass transition temperature. SLS analysis of the final product resulted in a weight average molecular weight of 83.6 kDa. The spectroscopic and thermal analyses proved that amphiphilicPHEA-g-PmBA was successfully synthesized through HTP and NMP. [ABSTRACT FROM AUTHOR]

In this paper, poly (acrylamide-co-N-vinylcaprolactam) [poly(AM-co-NVCL)] hydrogels were modified by aqueous solution polymerization using sodium carboxymethyl cellulose (CMC-Na) and Laponite. Their properties were characterized by infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD), rheological testing, and scanning electron microscopy (SEM). The swelling kinetics showed that the equilibrium swelling ratio of the xerogel was influenced by the monomer ratio, crosslinking agent, and modifier content. As the Laponite and CMC-Na content increased, the compressive strength of the composite hydrogel increased, while the elongation at break decreased. The modified composite hydrogel exhibited dual sensitivity to pH and temperature. DSC and rheological tests indicated that CMC-Na functioned as a physical crosslinking agent in the system, and with the increase in CMC-Na content, the crosslinking effect was enhanced. SEM demonstrated that the addition of Laponite and CMC-Na increased the number of pores in the hydrogel and decreased the pore size. [ABSTRACT FROM AUTHOR]

Thermal analysis is widely employed for the characterization of nanomaterials. It encompasses a variety of techniques that allow the evaluation of the physicochemical properties of a material by monitoring its response under controlled temperature. In the case of carbon nanomaterials, such as carbon nanotubes and graphene derivatives, thermogravimetric analysis (TGA) is particularly useful to determine the quality and stability of the sample, the presence of impurities and the degree of functionalization or doping after post-synthesis treatments. Furthermore, TGA is widely used to evaluate the thermal stability against oxidation by air, which can be, for instance, enhanced by the purification of the material and by nitrogen doping, finding application in areas where a retarded combustion of the material is required. Herein, we have evaluated key parameters that play a role in the data obtained from TGA, namely, gas flow rate, sample weight and temperature rate, used during the analysis. We found out that the heating rate played the major role in the process of combustion in the presence of air, inducing an increase in the temperature at which the oxidation of CNTs starts to occur, up to ca. 100 °C (from 1 °C min−1 to 50 °C min−1). The same trend was observed for all the evaluated systems, namely N-doped CNTs, graphene produced by mechanical exfoliation and N-doped reduced graphene samples. Other aspects, like the presence of impurities or structural defects in the evaluated samples, were analyzed by TGA, highlighting the versatility and usefulness of the technique to provide information of structural aspects and properties of carbon materials. Finally, a set of TGA parameters are recommended for the analysis of carbon nanomaterials to obtain reliable data. [ABSTRACT FROM AUTHOR]

Poly(vinyl alcohol) (PVA)-based films have drawn significant attention owing to their potential applications in various industries. The application of wax to PVA films enhanced their resistance to dissolution and water infiltration. Nevertheless, waxed PVA films often exhibit inadequate mechanical properties owing to crack formation. In this study, we evaluated the impact of glycerol as a plasticizer in varying concentrations of Carnauba wax (CW). The addition of glycerol to the PVA/CW blend led to enhanced mechanical properties compared to the blend without glycerol. The functional group and morphology of the blends confirm glycerol compatibility with PVA/CW films. Glycerol was fully dispersed to form a consistent polymer matrix and equally improved the film's contact angle. Furthermore, the thermal property from differential scanning calorimetry and thermogravimetric analysis highlights the plasticizing effect of glycerol in PVA/CW films, potentially broadening their use in food packaging and wrapping applications. [ABSTRACT FROM AUTHOR]

Microparticles derived from biomaterials are becoming increasingly popular for application in drug delivery systems. In this study, the water-in-oil (W/O) emulsification–diffusion method was used to create cellulose (C), silk fibroin (SF), and C/SF composite microparticles. We then observed the morphology of all obtained microparticles using scanning electron microscopy (SEM), evaluated their functional groups using attenuated total reflection–Fourier transform infrared spectroscopy (ATR-FTIR), and conducted thermogravimetric analysis using a thermogravimetric analyzer (TGA). SEM micrographs indicated that the native SF microparticles have the highest spherical shape with smooth surfaces. With blue dextran, the C microparticle was smaller than the native microparticle, while the drug-loaded SF microparticles were larger than the native microparticle. The morphological surfaces of the C/SF composite microparticles were varied in shape and surface depending on the C/SF ratio used. The spherical shape of the C/SF composite microparticle increased as the SF content increased. Furthermore, the size of the drug-loaded C/SF composite microparticles increased when the SF content gradually increased. The significant functional groups in the C and SF structures were identified based on the ATR-FTIR data, and a suggestion was made regarding the interaction between the functional groups of each polymer. When compared to both native polymers, the C/SF composite microparticles exhibit improved thermal stability. XRD patterns indicated that all prepared particles have crystalline structures and are directly affected by the released profile. The C/SF composite microparticle at a 1:3 ratio had the lowest drug release content, whereas the hydrophilicity of the C microparticle affected the highest drug release content. As a result, one crucial factor affecting the medication released from the microparticle is its structure stability. According to the obtained results, C, SF, and C/SF composite microparticles show promise as delivery systems for drugs with controlled release. [ABSTRACT FROM AUTHOR]

Injectable and temperature-responsive Poly(N-Isopropylacrylamide) (PNIPAAm)/Chitosan composite hydrogels reinforced with cellulose nanocrystals (CNCs) were successfully fabricated via photopolymerization. 0.1–3% (w/v) of cellulose nanocrystals were incorporated into the PNIPAAm/chitosan matrix to form thermo-responsive injectable composite hydrogels. FT-IR spectra confirmed the successful formation of these hydrogels, highlighting the characteristic peaks PNIPAAm, chitosan and CNCs. The inclusion of CNCs led to a reduced pore size as compared to the control hydrogels. The mechanical properties of the hydrogel were characterized under various temperature conditions. Rheology tests showed that storage modulus (G′) increased significantly above 30 °C, indicating gel-like behavior. Thermogravimetric analysis showed thermal stability up to 300 °C. The volume phase transition temperatures (VPTT) of the hydrogels were found to be in the range of 34–38 °C, close to physiological body temperature. The equilibrium swelling ratio (ESR) of the CNC-containing hydrogels was higher than that of the control. In vitro studies with Human Dermal Fibroblast adult (HDFa) cells showed the hydrogels to be non-toxic, suggesting their potential for biomedical applications. [ABSTRACT FROM AUTHOR]

Energy from municipal sewage sludge can be obtained by applying a thermal conversion method. In this study, the combustion kinetics of municipal sewage sludge were analyzed in an O2/CO2 atmosphere. Studies were conducted in different gaseous atmospheres consisting of varying proportions of oxygen and carbon dioxide. The participation of oxygen was as follows: 20, 40, 60, 80 and 100% vol. The experimental temperatures varied from 873 to 1273 K. The experimentally obtained results helped establish the basic kinetic parameters, such as the reaction order n, factor Ko and activation energy Ea of sludge grains. The values of the activation energy Ea and Ko were, respectively, 46 kJ/mol and 0.0127 mg/m2sPa. They show that the limiting factor of combustion is the diffusion of oxygen and that combustion reactions take place in the outer layer of the unreacted core. Therefore, sludge is promising for energy recovery because it has quite a high net calorific value (NCV) and a high gross calorific value (GCV). The GCV was 14.1 MJ/kg and the NCV was 12.8 MJ/kg. The experimental studies with a wide range of process parameters helped to create an array of apparent reaction rates as a function of the temperature and oxygen concentration, showing the significant effect of oxygen on the apparent reaction rate, in contrast to the effect of temperature. [ABSTRACT FROM AUTHOR]

Preventing severe corrosion incidents caused by air ingress accidents in high-temperature gas-cooled reactors (HTGRs) while improving heat removal efficiency from the core is of paramount importance. To enhance both safety and efficiency, a sleeveless silicon carbide (SiC)-matrix fuel compact has been proposed. This study evaluates the 10-hour oxidation of reaction-sintered SiC (RS-SiC)-matrix fuel compact under the conditions of an air ingress accident within the temperature range of 1000 to 1400 °C. The oxidation tests were conducted in a stagnant air environment without flow. As a result, it is demonstrated that RS-SiC exhibits exceptional resistance to air oxidation up to 1400 °C, as shown by the thermogravimetric analysis (TGA), with minimal mass loss due to the oxidation of free carbon. Scanning electron microscopy with energy-dispersive X-Ray spectroscopy (SEM–EDX) analysis reveals that the morphology and thickness of the SiO2 layer formed on the RS-SiC surface vary with temperature. At 1400 °C, uniform oxide layer thickness ranging from 1.59 to 4.10 μm and localized nodule-like oxide formations of approximately 10 μm are observed. In contrast, at 1000–1200 °C, thinner oxide layers are identified, indicating that oxide growth accelerates at higher temperatures. The oxidation rates measured provide insights into the mechanisms of oxide growth. [ABSTRACT FROM AUTHOR]

In this work, Gum ghatti-cl-poly(acrylic acid)/CoFe2O4 (GGAACF) hydrogels were synthesized using a free radical polymerization technique, with CoFe2O4 nanoparticles incorporated via a co-precipitation method using nitrates as precursors. Thermal gravimetric analysis (TGA) revealed that the inclusion of CoFe2O4 nanoparticles enhanced the thermal stability of the hydrogels. Swelling studies indicated that the addition of 30 mg of CoFe2O4 nanoparticles maximized water retention. Rheological assessments demonstrated non-Newtonian behavior, with flow curves fitted best by the Power Law model. The incorporation of CoFe2O4 nanoparticles significantly improved the hydrogel's elasticity and viscosity, as evidenced by a higher storage modulus (G′) compared to the loss modulus (G″) across all frequencies, indicating the elastic nature of the hydrogels. The decrease in complex viscosity with increasing frequency confirmed the pseudoplastic properties of the hydrogels, attributed to the random alignment of CoFe2O4 nanoparticles within the matrix. Tan δ values were below unity at all tested frequencies, underscoring the hydrogels' strong elastic properties. These findings highlight the effectiveness of rheological analysis in characterizing the viscoelastic behavior of polymer hydrogels, which can be tailored for various applications. [ABSTRACT FROM AUTHOR]