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Polyimide materials with high mechanical strength are widely used in various fields, but pose certain challenges in achieving sustainable material utilization. A poly(imide‐imide) vitrimer material (ADTA) based on multiple dynamic covalent bonds (imide, imine, and disulfide bonds) was constructed by preparing vanillin difunctionalized derivatives (DVA) for aldolamine condensation reactions with bis‐amine monomers (ATFA) and tris(2‐aminoethyl) amines (TAEA) with imide structures. The ADTA material has good 5% thermal stability Td5% (278.87°C), high energy storage modulus E (2421.26 MPa), and fast relaxation time (36.39 s). The thermal stability and mechanical properties of the material are enhanced by the more stable alicyclic structure of the imide structure. The material also demonstrated excellent solvent resistance and self‐healing properties. This study provides a new option for the development of sustainable utilization of polyimide materials. [ABSTRACT FROM AUTHOR]

The study aimed to explore the influence of pre-oxidation oxygen concentration on the mass variation and microstructure of coal oxidation using TG and FTIR experiments. The objective was to comprehend the thermal effects and mechanisms of coal oxidation under distinct pre-oxidation conditions. Employing fuzzy mathematics and multiple linear regression equations, the study sought to elucidate the influence mechanism of pre-oxidation oxygen concentration on the thermal effect. The findings reveal that pre-oxidation did not alter the overall weight loss pattern during the spontaneous combustion process of coal, yet significantly accelerated the rate of weight loss. Furthermore, the dry cracking temperature experienced a notable advancement. Through FTIR experiments, it was observed that pre-oxidation activated the reactivity of C=O, -CH2-, and aromatic hydrocarbons, thus leading to more intense reactions. The key functional groups influencing the mass change were identified as aromatic hydrocarbons and hydrogen bonds. Notably, the pre-oxidation effect on the thermal impact was most pronounced when the pre-oxidation oxygen concentration reached 15%. [ABSTRACT FROM AUTHOR]

Polyethylene (PE) foams are widely used for the advantages of light weight and reducing energy consumption. So, the preparation of environmental friendly and efficient blowing agent is essential. The use of supercritical carbon dioxide (CO2) as physical blowing agent requires harsh experimental conditions such as high‐pressure and temperature. In this study, CO2 was captured by 1, 2‐cyclohexanediamine (TRK) under atmospheric pressure, and reversibly released under heating as a blowing agent with nanosponges (NS) used as the carrier (NS:TRK‐CO2). Furthermore, three ethoxy silane coupling agents were selected to improve the compatibility between heterogeneous nucleating agent (cyclodextrin nanosponges, NS) and PE, so as to improve the nucleation effect of NS and the comprehensive properties of PE composites. Analyses showed that triethoxyvinyl silane (VTES) was a suitable candidate for improving the compatibility of NS and PE. The addition of NS:TRK‐CO2@VTES not only improved the crystallization performance, but also improved the complex viscosity and storage modulus, and enhanced the thermal properties of PE composites. The optimal cell morphology was obtained by introduction of NS:TRK‐CO2@VTES with 5 wt%, the minimum cell diameter was 50 μm, and the maximum cell density was 9.4 × 104 cells/cm3. Compared with the other PE composites, PE/NS:TRK‐CO2@VTES composites showed excellent mechanical, thermal, and sound insulation properties. The maximum impact strength was 7.62 KJ/m2, which was two times higher than pure PE. The thermal conductivity was 0.054 W/m k, the sound absorption coefficient was 0.836 at 1500 Hz. [ABSTRACT FROM AUTHOR]

To improve the mining efficiency of geothermal energy, this paper designed a mode II fracture test of double-edge notched cube granite samples after a thermal shock to study the shear fracture characteristics of hot dry rocks. First, the effects of temperature and normal stress on the shear parameters such as shear strength, cohesion, and internal friction angle of the specimens were analyzed. Then, the evolution of the specimens' morphology parameters such as fractal dimension and joint roughness coefficient were investigated. Finally, a multi-scale analysis of the differences between shear and morphology parameters was conducted based on thermogravimetric analysis and scanning electron microscope technology. The results show that the specimens' shear and morphology parameters have a quadratic function relationship with temperature and a linear positive correlation with normal stress. The threshold temperature of samples is 256.36 °C. When the thermal shock temperature is lower than the threshold temperature, the shear parameters strengthen and the morphology parameters decrease. Conversely, the shear parameters weaken, and the morphology parameter increases. The height of the bulges on the shear surface increases along the shear direction, resulting in an obvious climbing phenomenon. The mode II fracture characteristics of the samples can be described using the dislocation slip theory and rock bridge weakening mechanic model. The area of scratches on the shear surface can be used as a macroscopic representation of the morphology parameters. Water evaporation/separation and mineral dehydration/phase transition inside the granite samples are the main reasons for the differences between shear and morphology parameters. Highlights: Mode II fracture test on double-edge notched cube granite after thermal shock. Thermogravimetric technology is used to determine the threshold temperature. There is a climbing phenomenon along the shear direction on the shear surface. The samples' fracture characteristics obey rock bridge weakening mechanic model. Scratch can be used as a macroscopic representation of the morphology parameters. [ABSTRACT FROM AUTHOR]

Biomass, hydrochar, coal and hydrochar/coal blends have been proposed as alternative energy sources to coal. Given that the new fuels are derived from biomass, which is highly reactive, it is necessary to investigate their potential for spontaneous combustion (SPONCOM). Through the characteristics of coal discard, biomass, hydrochar, and hydrochar mixed at different ratios with discard coal, this study examined the factors that contribute to SPONCOM. The SPONCOM liability of these fuels was examined using the thermogravimetric analysis (TGA) and the Wits-Ehac index. The physicochemical analysis revealed an increase in the energy characteristic of the hydrochar produced from biomass. All samples showed a transmittance of the C=O stretch, which promotes SPONCOM, according to the results of the Fourier Transform Infrared Spectroscopy (FTIR) analysis. The TGA findings revealed that biomass is highly reactive, while discard coal was found to be non-reactive. A significant correlation was seen between the $T{G_{spc}}$ T G spc index and the physiochemical properties of the samples. The Wits-Ehac results showed that biomass had the lowest SPONCOM liability index, while the 50% hydrochar/50% discard coal blend had the highest SPONCOM liability index. There was no correlation between the TGA and Wits-Ehac results, as the Wits-Ehac results showed some inconsistencies, particularly for samples derived from biomass. This study establishes the mechanism responsible for SPONCOM of hydrochar blended with coal in relation to their properties using the TGA. In addition, contributed to the understanding of techniques for predicting the SPONCOM of likely fuels for this application. [ABSTRACT FROM AUTHOR]

Bio-polymer composites are emerging as a feasible substitute for conventional polymers in various major fields of applications. In the current research, the impact of hybridization of inter and intra-woven natural engineering fibers namely, brown flax, white flax, and jute of different amalgamations along with commingled SCF and novel nano IW filler has been studied. The composites are manufactured by hand layup process and physical and thermomechanical characteristics of the composites are experimentally studied. The composites mingled with IW filler demonstrated better dimensional stability and mechanical properties such as maximum tensile strength of 36.74 MPa, bending strength of 82.53 MPa, and hardness of 84.89 D compared to other composites. However, elastic and flexural modulus are maximum for composite without any filler. The composites mingled with SCF filler demonstrated the highest impact strength, energy absorption, and elongation. Thermogravimetric analysis and thermal conductivity study demonstrated that the composite with SCF filler exhibited better thermal stability and thermal resistance than the other hybrid composites. Fourier transform infrared spectroscopy study confirms the interaction of hydrogen bonds with different polymers, matrices, and fillers. It is established that the weaving pattern and the filler types greatly influences the mechanical and thermal characteristics of the composites. Filler addition and fabric hybridization optimizes the catastrophic failures and enhances the thermal stability, hence becoming more suitable for small interior structural components in aerospace and automobile applications. [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]

In this study, β-diketone derivative new carboxamide Eu(III) and Tb(III) lanthanide complexes were synthesized and characterized by FT-IR, elemental analysis, UV–Vis, and molar conductivity techniques. There is no electrolytic conductivity in the compounds. Moreover, the photoluminescence properties and thermal behavior of the synthesized lanthanide complexes were investigated. Photoluminescence data revealed that the Tb(III) complex showed metal-based f-f transitions. The β-diketone derivative carboxamide ligand exhibited as antenna that transmitted the excited energy to the emission energy levels of the Tb(III) ion. These metal complexes were screened in two different common cancer cell lines and a human normal embryonic kidney cell line for 48 h. The results showed that these complexes have more antiproliferative activities in the colon cancer cell line compared to the lung cancer cell line. [ABSTRACT FROM AUTHOR]

The objective of this work was to produce and use green pea pod lignin for improving the thermal stability, flammability, and creep resistance of pineapple fibre-reinforced epoxy composite. The lignin macromolecules are derived from waste green pea pods via thermo-chemical process and used as reinforcement. The composites were made using the compression moulding method followed by post curing at 120°C. The prepared composites are then machined for testing according to ASTM standards. The results of this research demonstrate that the decomposition temperature of the composite known as EF is improved by the incorporation of pineapple woven mats by a volume of 40%. Comparing to all the composite designations, the EFL3 offers the least loss of weight, the highest decomposition temperature (approximately 420°C), the highest storage modulus (about 7.5 GPa), and the lowest loss tangent (0.6). Accordingly, the EFL3 composite designation has been reported to have the lowest combustion rate of 5.88 mm/min and the highest DSC value of 0.6 mW/mg. However, the creep strain is reduced when adding lignin by 0.5, 1.0, and 2.0 vol. %. These eco-friendly waste converted green pea pod lignin strengthened pineapple fibre-epoxy composites could be used in high thermal applications including automotive insulation panels and domestic infrastructure. [ABSTRACT FROM AUTHOR]

The composition, structure, and morphology of dehydrated sewage sludge, a by-product of pulp and paper production, were studied. The thermal characteristics of sewage sludge were investigated. An elemental analysis of the sewage sludge was carried out, the results of which revealed a large number of noncombustible elements (5.5%), including heavy metals (vanadium, chromium, nickel, zinc, and strontium), compared to other types of fuel. Thermogravimetric studies on the thermal decomposition of dehydrated sediment were carried out. The thermogravimetric and differential thermogravimetric curves were described, and the temperature ranges of drying, release of volatile substances, and combustion of coke residue were determined. Microscope photos showed that the particle size of the sediment varied from 0.5 and 350 nm, and amorphous flakes and crystalline inclusions were the main elements of its structure. [ABSTRACT FROM AUTHOR]

In this work, a study of chicken litter pyrolysis was carried out in a thermal analyzer in a temperature range from 20 to 905°C at different heating rates of the raw material. Four peaks were obtained in a graph of the temperature dependence of the rate of weight loss. The first and second peaks were associated with the decomposition of plant biomass components; the third peak was due to the decomposition of plant and manure components, and the fourth peak characterized the decomposition of compounds from the mineral part of chicken manure. Spectral analysis of the gaseous products of chicken litter pyrolysis showed that they contained flammable components typical of gaseous products of thermal decomposition of plant biomass. The temperature range of the most intense formation of main carbon-containing compounds was 140–380°C. In addition, nitrogen-containing compounds associated with the decomposition of urea and proteins from chicken manure were found in the volatile components. [ABSTRACT FROM AUTHOR]

This study explored the extraction, characterization, and encapsulation of black cardamom oleoresin (BCO) for its potential applications in spices and other pharmaceutical industries. Solvent-extracted black cardamom with food-grade ethanol yielded concentrated oleoresin rich in bioactive compounds, viz., 1, 8-cineole (41.97%), α-terpineol (14.68%), α- terpinene (4.82%), and α-terpinyl acetate (4.70%), as confirmed by gas chromatography-mass spectroscopy (GC‒MS) analysis. Freeze-drying successfully preserved the stability and quality of the encapsulated powder, with analyses confirming low moisture content (2.49–3.51%) and water activity (aw) (0.44 to 0.52). Additional evaluation, such as powder flow property and thermal analysis, is crucial for ensuring the quality and stability of the encapsulates. Color properties, Fourier transform infrared-attenuated total reflectance (FTIR-ATR) spectroscopy, micro-Raman spectroscopy, and X-ray diffraction (XRD) analysis confirmed successful encapsulation and indicated structural changes post-encapsulation. Among the encapsulating materials employed, gum arabic (GA) exhibited the highest encapsulation efficiency at 64.71%. Thermogravimetric analysis (TGA) indicated good thermal stability and decomposition characteristics, as evidenced by a residual mass loss of 8.06%. Notably, oleoresin encapsulated with gum Arabic (GA) retained higher DPPH antioxidant activity (66.36 ± 1.02%) and phenolic content (80.27 ± 0.11 mg GAE/g) compared to other encapsulates. Principal component analysis (PCA) highlighted the impact of individual components on the overall quality and functionality of the encapsulated product. This work provides a valuable resource for developing encapsulated black cardamom oleoresin (BCO) with detailed studies on method of extraction and encapsulation materials to enhance the stability of oleoresin and to explore effective applications in various industries. [ABSTRACT FROM AUTHOR]

Investigating the thermal hysteresis and its effect on the kinetic behaviors and reaction model of vacuum residue pyrolysis is of significant importance in industry and scientific research. Effects of heating rate and heating transfer resistance on the pyrolysis process were examined with the thermogravimetric analysis. The kinetic characteristics of the vacuum residue pyrolysis were estimated using the iso-conversional method and integral master-plots method based on a three-stage reaction model through the deconvolution of Fraser-Suzuki function. Results showed that the reaction order models for the first and second stages were associated with the evaporation of vapor, while the nucleation and growth models for the third stage were linked to char formation. During the pyrolysis, the thermal hysteresis led to an increase in the reaction order in the first stage, which resulted in a delayed release of generated hydrocarbons due to high heating rate and enhanced heat transfer resistance. The reaction in the last stage primarily involved coking, where the presence of an inert solid acted as a nucleating agent, facilitating char formation and reducing the activation energy. The optimization results suggest that the obtained three-stage reaction model and kinetic triplets have the potential to effectively describe the active pyrolysis behavior of vacuum residue under high thermal hysteresis. [ABSTRACT FROM AUTHOR]

An experimental platform for fine water mist inhibition of polyurethane fire was set up to study the inhibition of polyurethane fire by a new type of spray nozzle fine water mist containing additives. The combustible material chosen for the experiment was polyurethane insulation foam board, a cold storage insulation material. Firstly, a venturi was installed in front of the nozzle, secondly, a surface tension meter was used to test the surface tension of the additives, and the pyrolysis products of the composite additives were analyzed by thermogravimetric analysis, and finally, the pressure was adjusted and a fine water mist with a concentration of 1% of the composite additives, and NaCl, CHSO4Na, KHCO3, and CO(NH2)2 were used to extinguish the polyurethane fire. The effectiveness of the fine water mist system in extinguishing fires at low concentrations of a single NaCl and green additive was investigated. The homemade additive package and the sodium chloride salt fine water mist system were compared. The experimental results showed that the synergistic effect of the physical and chemical additives significantly increased the suppression of polyurethane fires by fine water mist by about 16.7% relative to a single sodium chloride additive. [ABSTRACT FROM AUTHOR]

ABSTRACT Herein, we report the synthesis of an (E)‐N‐(pyridine‐3‐ylmethylene)pyridine‐2‐amine Schiff base (ENppa) and its Cu (II) complex (Cu‐ENppa) using 2‐aminopyridine (2APy) and pyridine‐3‐carbaldehyde (P3C). This study aimed to investigate the ADMET profiles, electronic features, antibacterial and anticorrosion activities of the synthesized ligand, and its Cu (II) complex. The compounds were characterized using various techniques, including CHN analysis, FT‐IR, 1H and 13C NMR, MALDI‐TOF MS, ICP‐MS, SEM, TGA/DTA, UV–visible spectroscopy, and powder X‐ray diffraction (PXRD). The Cu (II) ion exhibited tetrahedral geometry in the complex by coordinating with two nitrogen atoms, one from an imine group and the other from a pyridine ring. UV–visible spectroscopy and magnetic moment data also supported this geometry. TGA/DTA revealed three stages of decomposition at 141°C°C–255°C, 255°C°C–367°C, and 549°C°C–659°C, with CuO as the final residue. PXRD analysis identified ENppa and Cu‐ENppa as nanocrystallites, with crystallinities of 82% and 49%, respectively. Both compounds were highly effective in inhibiting mild steel corrosion in acidic media, with inhibition efficiencies of 97% and 98%, respective for Cu‐ENppa and ENppa. They also exhibited favorable ADME profiles, indicating potential as drug candidates for in silico ADME studies. The antibacterial activity results demonstrated promising efficacy, with Cu‐ENppa showing higher activity than ENppa. [ABSTRACT FROM AUTHOR]

As for cellulose‐based aerogels, a feature of inadequate mechanics and easy‐flammability seriously restricts their practical applications. To address this issue, herein a lightweight, mechanical elastic and flame‐retardant phosphorylated lignin‐based cellulose nanofiber (PLCNF‐B) aerogel with the aid of boric acid was successfully obtained by freeze‐drying method. Due to the uniform and tough network structure benefitting by strong hydrogen bond between phosphorylated fibers and boric acid, the resultant aerogel showed excellent mechanical performance, that is, high compressive strength of 8.9 kPa (strain: 50%) and outstanding cyclic reliability (remain 90% after 10 cycles). Meanwhile, PLCNF‐B aerogel possesses highly improved flame‐retardant property, that is, a high LOI value (up to 46%), significantly reduced peak heat release rate (11.2 W/g) and total heat release rate (0.47 kJ/g). Based on structural observation and analysis, the flame‐retardant behavior should be attributed to the formation of PxOy/amorphous boron oxide protective layer, which is derived from the phosphorus containing group of PLCNF and boric acid. The splendid overall performance of aerogel material offers a potential material tactic for design and development of advanced bio‐based aerogels for practical applications. [ABSTRACT FROM AUTHOR]

Thermogravimetric analysis (TGA) was performed on six samples of pine wood, poplar sawdust and olive residue, and the kinetic parameters were evaluated by using isoconversional models. The hemicellulose, cellulose and lignin contents were also estimated using the Fraser–Suzuki deconvolution method. In addition, a range of thermodynamic parameters and combustion indices was calculated. Significant correlations were found between the kinetic, thermodynamic and combustion parameters. The ignition index showed an inverse relationship with the activation energy, whereas the burnout index correlated with enthalpy values for most samples. Higher heating rates during TGA increased ignition and combustion efficiencies but decreased combustion stability. Differences in behaviour were detected between the olive residues, which had a much higher lignin content (51.2–56.9%), and the woody biomass samples (24.2–29.2%). Moreover, the sample with the highest ash content also exhibited some distinctive characteristics, including the lowest high heating value and ignition index, coupled with the highest activation energy, indicating a less favourable combustion behaviour than the other samples. The particle size of the samples was also found to be critical for both combustion efficiency and safety. [ABSTRACT FROM AUTHOR]

Coal remains one of the most used solid fuels for heat and electricity generation but burning coal releases large amounts of CO2 into the urban atmosphere in addition to harmful substances. In order to reduce the consumption of solid fossil fuels, it is necessary to search for fuels capable of replacing coal in terms of its thermal and environmental characteristics. One of the best alternative fuels is biomass, which is considered carbon neutral, but its thermal characteristics are worse than those of solid fossil fuels. In this work, an alternative to coal was studied for the first time, which was semi-coke, obtained by gasification at a temperature of 700–900 °C, the heat of combustion of which turned out to be higher than that of biomass before thermal treatment by 75%. We also studied fuel mixtures based on the resulting semi-coke. The aim of the work is to determine the main characteristics of combustion of semi-coke obtained from coniferous wood and mixtures based on them. The method of thermogravimetric analysis in oxidising medium at a heating rate of 20 °C/min was applied for the research. According to the results of this analysis, the ignition and burnout temperatures were determined, the combustion index was determined, the duration of coke residue combustion was determined, and synergetic interactions between the mixture components influencing the combustion characteristics were established. It was found that the ignition temperature of semi-coke is more than 50% higher than that of biomass and the burnout temperature is 10% higher. Adding 50% of biomass to semi-coke increases the combustion index by more than 30% and decreases the ignition temperature and burnout temperature. The mixture components synergistically interact with each other during combustion to reduce the value of maximum mass loss rate. It was found that the atomic ratios of O/C and H/C in semi-coke are lower than in biomass before gasification. [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]

A tremendous amount of waste black tea bags (BTBs) and date palm surface fibers (DPSFs), at the end of their life cycle, end up in landfills, leading to increased pollution and an increase in the negative impact on the environment. Therefore, this study aims to utilize these normally wasted materials efficiently by developing new composite materials for thermal insulation and sound absorption. Five insulation composite boards were developed, two were bound (BTB or DPSF with polyvinyl Acetate resin (PVA)) and three were hybrids (BTB, DPSF, and resin). In addition, the loose raw waste materials (BTB and DPSF) were tested separately with no binder. Thermal conductivity and sound absorption coefficients were determined for all boards. Thermal stability analysis was reported for the components of the tea bag (string, label, and bag) and one of the composite hybrid boards. Mechanical properties of the boards such as flexural strain, flexural stress, and flexural elastic modulus were determined for the bound and hybrid composites. The results showed that the thermal conductivity coefficients for all the hybrid composite sample boards are less than 0.07 at the ambient temperature of 24 °C and they were enhanced as the BTB ratio was reduced in the hybrid composite boards. The noise reduction coefficient for bound and all hybrid composite samples is greater than 0.37. The composite samples are thermally stable up to 291 °C. Most composite samples have a high flexure modulus between 4.3 MPa and 10.5 MPa. The tea bag raw materials and the composite samples have a low moisture content below 2.25%. These output results seem promising and encouraging using such developed sample boards as eco-friendly thermal insulation and sound absorption and competing with the synthetic ones developed from petrochemicals in building insulation. Moreover, returning these waste materials to circulation and producing new eco-friendly composites can reduce the number of landfills, the level of environmental pollution, and the use of synthetic materials made from fossil resources. [ABSTRACT FROM AUTHOR]

Efficient pretreatment methods are crucial for the generation of fermentable sugars from the renewable lignocellulose. In this study, γ-valerolactone (GVL), a biomass-derived green solvent, was used to fractionate corn stover (CS). The impact of different additives on the enzymatic hydrolysis and pretreatment of CS within the GVL/water system was carefully investigated. The results demonstrate that the use of H 2 SO 4 -assisted GVL/H 2 O (80:20, w/w) pretreatment at mild conditions successfully facilitates the depolymerization of CS, thereby improving the cellulase accessibility. Furthermore, by increasing the GVL pretreatment temperature to 160 °C with 100 mM H 2 SO 4 addition, the pretreated CS led to nearly 100 % of hydrolysis yield at 2 % (w/v) solid load. Finally, the thermogravimetric analysis (TGA) was performed to evaluate the thermal decomposition characteristics of untreated CS and enzymatic residues based on the H 2 SO 4 -assisted GVL/H 2 O pretreatment. The results indicate that the enzymatic residues had two depolymerization stages from 200 °C to 500 °C with a final residual mass of 22.73 %, which was higher than that of untreated CS (20.56 %). Overall, this study provides an efficient lignocellulose pretreatment for fermentable sugars production and valorization of enzymatic residues. [Display omitted] • Using H 2 SO 4 as γ-valerolactone (GVL) pretreatment additive enhanced xylan removal. • Glucose yield of GVL-pretreated corn stover (CS) was 3–5 folds higher than raw CS. • Sugars production reached 32.4 g/100 g CS by 50 mM H 2 SO 4 -assisted GVL pretreatment. • Enzymatic residues had two decomposition stages in 200–500 °C by thermal analysis. [ABSTRACT FROM AUTHOR]

As a typical forestry waste, bamboo has gained increasing attention for its potential applications. In order to optimize its valorization, understanding the kinetic and thermodynamic parameters of bamboo pyrolysis and combustion is crucial. In this study, thermogravimetric analysis (TGA) was employed to examine bamboo powder's pyrolysis and combustion behaviors under different temperature ramps in nitrogen and air environments, and the kinetic and thermodynamic parameters were evaluated using the Flynn–Wall–Ozawa (FWO), Kissinger–Akahira–Sunose (KAS), and Starink (STR) model-free approaches. The main findings are as follows. (1) The thermogravimetry (TG) and derivative thermogravimetry (DTG) (DTG) curves reveal that bamboo pyrolysis occurs in three distinct stages: drying, devolatilization, and carbonization. Similarly, combustion also proceeds through three stages: drying, devolatilization, and char combustion. Notable differences in the temperature ranges of the key stages were observed between pyrolysis and combustion. (2) The activation energies during the oxidative devolatilization stage of combustion are notably lower compared to those during pyrolysis devolatilization. The disparity in activation energy is even more pronounced in the third stage. (3) Thermodynamic analysis shows that the pyrolysis and combustion of bamboo are endothermic and non-spontaneous. It can be stably converted into value-added energy through the pyrolysis or combustion process. This study provides essential data to aid in designing and scaling up the thermochemical conversion processes for bamboo and promote its efficient valorization of bioenergy. [ABSTRACT FROM AUTHOR]

The present paper aims to elucidate the bioenergy potential of the invasive grass Eleusine indica based on its physicochemical characterization, pyrolysis kinetics, and thermodynamic parameters. The pyrolytic behavior of E. indica acquired from non-isothermal thermogravimetric experiments was kinetically represented by three independent parallel reactions, each corresponding to one pseudo-component (pseudo-hemicellulose (P-HC), pseudo-cellulose (P-CL), and pseudo-lignin (P-LG)). The pseudo-components were typified by their kinetic triplets (Ea, A, and f(α)) and thermodynamics parameters (ΔH, ΔG, and ΔS). The average activation energy values of E. indica pyrolysis estimated from four isoconversional methods (Friedman, Flynn–Wall–Ozawa, Kissinger–Akahira–Sunose, and Starink) varied between 98.5 and 101.8 kJ mol−1 for P-HC, 113.7 and 123.4 kJ mol−1 for P-CL, and 205.3 and 236.0 kJ mol−1 for P-LG. Pre-exponential factors of devolatilization of P-HC, P-CL, and P-LG estimated from the kinetic compensation effect were 1.73 × 109, 6.06 × 109, and 1.16 × 1019 min−1, respectively. The most plausible mechanisms for the E. indica pyrolysis included the F2 reaction model for P-HC, the A2 reaction model for P-CL, and the F6 reaction model for P-LG. The cumulative kinetic expression adequately represents the experimental kinetic curves, with R2 > 0.92 and Fit > 94.9%. Based on the thermodynamic analysis, the positive values of ΔH and ΔG showed that the E. indica pyrolysis was endothermic and nonspontaneous. In contrast, the ΔS was negative, revealing a lower reactive process characteristic. Overall, the results highlight the potential utilization of E. indica for bioenergy production and provide a solid basis for designing pyrolytic reactors using this invasive grass as a feedstock. [ABSTRACT FROM AUTHOR]

The electromagnetic frequency high-energy stir casting process was used to create the high-quality magnesium (Mg) dispersed with varied percentages of nano-sized B4C (0, 0.5, 1 and 1.5 wt%). The shape and distribution of Mg with nano B4C were validated by characterization research on nanocomposites utilizing energy-dispersive spectrum, scanning electron microscope and X-ray diffraction. Thermal and mechanical characteristics such as thermogravimetric analysis/differential thermal analysis and tensile strength were explored utilizing acoustic emission. During a tensile test, online monitoring using acoustic emission (AE) demonstrates a reduction in fracture development and propagation. The tensile test result exhibits that, Mg-1.5% B4C nanocomposite has a better tensile strength (σultimate = 125 MPa) than the Mg-0.5% B4C nanocomposite (σultimate = 115 MPa). AE results show that the hit begins at 26 µs for Mg-1.5% B4C nanocomposite, whereas for Mg-0.5% B4C nanocomposite, it begins at 14 µs. Thus, AE results show that an increase in B4C nanoparticles in the composites will prevent hits from occurring. The SEM and atomic force microscopy analyses were performed on the tensile-tested specimens to find the distinguishing characteristics. Owing to the inclusion of the B4C, the Mg-1.5% nano B4C composite has a longer ignition time in the thermogram of TGA and greater tensile strength than the Mg. [ABSTRACT FROM AUTHOR]

The work summarizes an innovative nanocomposite including synthesized copper nanoparticle (CuNP) impregnated wheat straw (WS) (the agronomic waste from an wheat plant) reinforced unsaturated polyester resin has been established. The addition of nanoparticles (NPs) increased the antifungal properties (~11%), durability (~9%), and strength (~39%) of the composites. Therefore, these nanoparticles have been synthesized from a copper chloride dihydrate precursor and they have been impregnated into wheat straw via cationization. This copper‐impregnated wheat straw (CuIWS) was formulated and employed to create a strong and long‐lasting nanocomposite with unsaturated polyester resin. Their morphological, mechanical, chemical, biodegradability (BD), and thermal properties were estimated and relationships were explicated systematically. Particularly, the tensile strength of polyester resin, crude and treated WS (cationized and copper‐impregnated) composites were 11.70, 14.20, 20.92, and 22.34 N/mm2 respectively. Therefore the reinforcement capability for crude, cationized and copper‐impregnated WS composites increased by ~22%, 75%, and 92% respectively. The residual ash was just about 16.23%, 12.04% and 6.56% for copper impregnated wheat straw composite (CuIWSC), Cationized wheat straw composite (CWSC) and untreated wheat straw composite (UTWSC) respectively point to the existence of ~4.1% Cu incorporated into the wheat straw which holds up the energy dispersive x‐ray (EDX) spectra of ~4.2% copper content. Thermogravimetric analysis (TGA) indicates that the nanocomposites are stable up to 325°C. These nanocomposites also show superlative crystallinity compared to other ones. Water uptake capacity followed typical Fickian diffusion law. The developed nanocomposites might be suitable for automobile and aircraft parts, furniture, and other indoor to outdoor applications. Highlights: TS of the composites increased by increasing the WS filling up to 15%.The crystallinity increased after the addition of nanoparticles.The typical water uptake properties followed the Fickian diffusion rule.Incorporation of nanoparticles increased 11% antifungal properties.The developed nanocomposites are used for inside and outside applications. [ABSTRACT FROM AUTHOR]

A series of poly(ether sulfone) random copolymers at various loading of diphenolic acid (DPA) units were synthesized and subjected to a comprehensive kinetics degradation study to assess their thermal behaviour. Poly(ether sulfones) were synthesized from different amounts of 4,4′dihydroxydiphenylsulfone, DPA and stoichiometric quantity of 4,4′-dichlorodiphenyl sulfone by nucleophilic aromatic displacement. The apparent activation energy (Ea) of degradation for the prepared compounds was determined by using a kinetics literature method, discussed and compared with each other and with those obtained in the past for similar polymers. The comprehensive thermal stability evaluation was completed with the assessment of the initial decomposition temperature of the prepared copolymer, showing a good thermal performance but, in the meantime, suggesting caution as regards the percentage of functionalization setting the limit beyond which a deterioration of the physical properties of the copolymers at 30% of pendant carboxylic acid groups was observed. [ABSTRACT FROM AUTHOR]

The black soldier fly (BSF) Hermetia Illucens can grow rapidly and on a wide variety of organic materials, and it is extensively used as a means of disposing of household organic waste. Different phases of the life cycle of BSF larvae (BSFL) are used in this work to extract chitin after the removal of lipids, mineral salts, and proteins. Multiple techniques, such as X-ray diffractometry, infrared spectroscopy, solid-state Nuclear Magnetic Resonance (13C ss-NMR) and thermogravimetric analysis, are used to investigate the chemical and physical characteristics of the extracted samples of chitin, which shows a high degree of acetylation (from 78% to 94%). The extracted chitin shows an increase of the thermal stability of 20 °C in the initial stage of life and 35 °C at the end of the life cycle if compared with a commercial standard. Moreover, the extracted chitin shows an increase in the crystallinity degree during the BSFL growth time (from 72% to 78%). [ABSTRACT FROM AUTHOR]

Simple physico-chemical techniques can be used to evaluate the composition, structure, and characteristics of plant seeds to determine their viability, quality, and possible uses in agriculture. Advanced analytical techniques, including thermo gravimetric analysis (TGA), electron paramagnetic resonance (EPR), and high-pressure liquid chromatography (HPLC), provide completely new insights and more precise information. They can be integrated to build up seed quality profiles, with great advantage to assess water content, organic compounds, and inorganic metals without the need to carry out many extraction procedures, as requested by more conventional methods. In this study, seed lots from three different plant species such as Triticum turgidum L. subsp. durum (wheat), Trigonella foenum graecum L. (trigonella or fenugreek), and Atriplex halimus L. (saltbush or sea orach) have been used to test the potential of TGA, EPR, and HPLC to discriminate between seed-specific features. A key finding of this study is that HPLC is essential in Principal Component Analysis (PCA) because various seeds (from the same species or other species) may contain compounds with varying polarity groups. The reported data confirm the efficacy of this approach. These data, fully available for other users, are coherently constructed and provide a proof of concept for future seed quality control studies. [ABSTRACT FROM AUTHOR]

The objective of this research is to address the rut problems in asphalt pavements and to resist the permanent plastic deformation with the increasing heavy traffic loads. In this paper, a new type materials of high modulus asphalt was developed by incorporating styrene–butadiene–styrene (SBS) and zinc oxide nanoparticles (nano ZnO) with an (EME)-type high modulus modifier, guided by the synergistic effects and the preparation methods of High-speed shear. The basic road performance, mechanical response and thermal stability of the new high modulus asphalt materials were analysed through basic physical indicator tests, dynamic shear rheometer tests, thermogravimetric analysis (TGA), the time–temperature superposition principle, the Refutas model, and the Christensen-Andersen-Marasteanu model. The optimal results demonstrate that the optimal blend ratio of the developed asphalt is 12% EME/8% SBS/1.5% ZnO. Under this composition, the road performance indicator values of softening point, penetration and ductility of the modified asphalt met the standard requirements. The dynamic shear rheometer tests demonstrates that the inclusion of SBS and nano ZnO considerably enhanced the shear resistance and recovery deformation capacity of EME, effectively improving the high-temperature deformation resistance of asphalt. Furthermore,the Refutas and the Christensen-Andersen-Marasteanu model fitting results showed that adding SBS and nano ZnO considerably improved the temperature sensitivity of the EME types high modulus modified asphalt and exhibiting low frequency sensitivity. Compared to PR Module-type high modulus modifier(PRM),TGA reveals that the maximum thermal weight loss of EME-SBS-ZnO decreased by 3.5441%, indicating better thermal stability and the major character of SBS,EME and asphalt is physical reaction. Moreover, EME-nano ZnO-SBS high modulus asphalt at 64 °C shows Jnr-diff = 9.5% and passes the "E" extreme traffic grade. Additionally, its cost is 4.67% lower than that of the PRM high modulus modified asphalt, presenting considerable economic benefits. [ABSTRACT FROM AUTHOR]

This work investigated the composites (PA6/BF) made of basalt fiber (BF) and nylon 6. To improve the interfacial bonding between the fibers and the polymer matrix, and to enhance the thermal and mechanical properties of the composites, polyhedral oligosilsesquioxanes (POSS) with epoxide groups was introduced to modify the surface of BFs using the slurry coating method. It is revealed that the mechanical properties of the composites increased and then decreased with increasing POSS coating. The composite PA6/BF‐POSS3 with BFs modified with a POSS solution of 3.0 wt% showed the best properties. The tensile strength of PA6/BF‐POSS3 was 130.8 MPa, 26.4% higher than that of the PA6/BF and 126.3% higher than that of neat PA6. In addition, PA6/BF‐POSS3 exhibited a 5% weight loss temperature of 417.7, 35.6°C higher than that of PA6/BF. The chemical bonding formed between the amide and epoxide groups, and the hydrogen bonding formed between the amide groups and hydroxyl groups were believed to be the main reasons for the improved interfacial interaction and improved properties. [ABSTRACT FROM AUTHOR]

China has abundant straw resources; however, the utilization of straw waste resource remains challenging. In this work, corn straw fiber and corn straw ash were applied to concrete as raw material after pretreatment. Through mechanical and thermal conductivity tests, it was concluded that the tensile strength of the corn straw fiber was 160.5 MPa after alkali treatment. The corn straw fiber and corn straw powder did not enhance the compressive strength of concrete. Compared with original concrete, the thermal conductivity of concrete added with 1.5% corn straw powder decreased by 25.9%, and the thermal conductivity of concrete with 5% corn straw ash was reduced by only 5.2%. Through thermogravimetric analysis of the concrete, it was found that the internal weakly bound water and strongly bound water will be lost in the range 100 °C to 160 °C, Ca(OH)2 will decompose from 420 °C to 500 °C, and CaCO3 will decompose approximately at 800 °C. It is recommended that corn straw powder and corn straw ash can be added at 1.5% and 5% concentrations to ensure that the mechanical properties can meet the engineering requirements and achieve good insulation performance. [ABSTRACT FROM AUTHOR]

This study introduces a methodology to easily estimate the composition of textile fibre mixtures, whether they are arranged in fabrics or fibre bundles, in order to assist the examination of fibre release from textiles, simplifying the process of analysis. The proposed method consists of the deconvolution of DTG signals, and the identification of the constituent associated with each peak. To assess the effectiveness of this method, the study analyses raw textile fibres, both individually and blended in different systems to characterize the thermal degradation of each one and their interaction when mixed. Such analysis of raw fibres is applied to commercial fabrics with known compositions and their released fibres in pilling experiments. The studied fibres are polyester (PET), cotton, wool and acrylic, while the blends encompass the systems PET + cotton, PET + wool, PET + cotton + acrylic. Hence, the method is evaluated. It can be applied to fast identification of textile compositions and can further aid in the identification of fibres in pilling tests. [ABSTRACT FROM AUTHOR]

The ammonium sulphate roasting process involves reacting mineral-bearing materials with ammonium sulphate via a solid–solid roasting process and subjecting the resulting roast residue to aqueous leaching. This process enables the simultaneous, non-selective co-extraction of strategic metals from the starting materials. However, effective separation of the extracted metals is often mandatory to produce quality products of high purity. In this study, the combined application of thermogravimetric analysis, X-ray powder diffraction and inductively coupled plasma optical emission spectrometry confirmed the non-selectivity of the process when applied to a South African diamond mine residue residue roasted with ammonium sulphate in a 1:2 mass ratio (m/m) at 450 °C for 2 h, with magnesium, iron and aluminium being co-extracted into water-soluble metal sulphates. Thermogravimetry was then applied to develop a multi-step, multi-temperature selective roasting process using mixtures of pure commercial metal sulphate salts. The first step of the modified process successfully separated iron and aluminium sulphates from magnesium-sulphates in the roast residues by thermally decomposing soluble iron and aluminium sulphates into insoluble oxides via calcination at 750 °C for 2 h. This temperature was lower than the one at which magnesium sulphates convert into magnesium oxide. In the second and final step, iron and aluminium were recovered from the oxide minerals via solid–solid re-roasting with ammonium sulphate at 450 °C for 1 h, causing the oxides to revert back to their water-soluble sulphate forms. The effectiveness of the modified process was subsequently verified using a diamond mine residue, showing that the soluble iron and aluminium contents in the magnesium-bearing leachate could be reduced by over 90%. [ABSTRACT FROM AUTHOR]

This work aims at comparing the ability of 7 modeling approaches to simulate the pyrolysis kinetics of spruce wood, wheat straw, swine manure, miscanthus and switchgrass. Measurements were taken using a thermogravimetric analyzer (TGA) with 4 heating rates comprised between 5 and 30 K min−1. The obtained results were processed using 3 isoconversional methods (Kissinger–Akahira–Sunose (KAS), Ozawa–Flynn–Wall (OFW) and Friedman), 1-step and 3-step Kissinger models, as well as an advanced fitting method recently proposed by Bondarchuk et al. [1] (Molecules 28:424, 2023, https://doi.org/10.3390/molecules28010424). Seventeen reaction models were considered to derive rate constant parameters, which were used to simulate the variation of the fuel conversion degree α as a function of the temperature T . To complement this benchmarking analysis of the modeling approaches commonly used to simulate biomass pyrolysis, a network model, the bio-CPD (chemical percolation devolatilization), was additionally considered. The suitability of each model was assessed by computing the root-mean-square deviation between simulated and measured α = f (T) profiles. As highlights, the model-free methods were found to accurately reproduce experimental results. The agreement between simulated and measured data was found to be higher with the Friedman model, followed by the KAS, FWO, 3-step, and 1-step Kissinger models. As for the bio-CPD, it failed to predict measured data as well as the above-listed models. To conclude, although it was less efficient than the Friedman, KAS or OFW models, the fitting approach from Bondarchuk et al. [1] (Molecules 28:424, 2023, https://doi.org/10.3390/molecules28010424) still led to satisfactory results, while having the advantage of not requiring the selection of a reaction model a priori. [ABSTRACT FROM AUTHOR]

We synthesized four new copper(II) complexes with acetato and chlorido ligands and methylammonium (MA), dimethylammonium (DMA), and tetramethylammonium (TMA) counterions: (MA)4[Cu2Ac4Cl2]Cl2·2H2O (1), (DMA)2[Cu2Ac4Cl2] (2), (DMA)4[Cu2Ac4Cl2]Cl2·2H2O (3), and (TMA)5[Cu2Ac4Cl]Cl4·4H2O (4). All compounds were characterized by single-crystal X-ray diffraction, magnetic measurements, FTIR spectroscopy, and thermogravimetric analysis. Complexes 1, 2, and 3 consist of a dinuclear coordination anion [Cu2(Ac)4Cl2]2− with bridging acetato ligands arranged in a paddle-wheel conformation and square-pyramidal coordination around Cu(II) atoms, while the coordination anion in compound 4 is a polymeric chain, parallel to the c axis, with Cu2(Ac)4 units connected through bridging chlorido ligands. Magnetic measurements carried out between 2 K and 300 K indicate strong antiferromagnetic interactions between Cu(II) ions. The effective magnetic moments range from 1.94   μ B to 2.21   μ B , exceeding the spin-only value for Cu(II) ions ( μ e f f = 1.73   μ B ) and suggesting significant orbital contributions to the magnetic moment. Thermogravimetric analysis of all complexes showed a multistep decomposition behavior yielding elemental copper as the final product. [ABSTRACT FROM AUTHOR]

AbstractFunctionally graded design transforms polymer composites without altering their properties. These composites change only the surface exposed to severe temperatures, leaving the rest unchanged. This study analyses ceramic additions’ effects on polymer thermal stability and crystallinity. Dynamic mechanical analysis (DMA) examined viscoelastic behaviour and thermogravimetric stability. Alumina, silicon carbide, and hafnium carbide ceramic powders increase thermal stability. DMA examined how ceramic additives affected composite viscoelasticity. The functionally graded design barely affects ceramic adhesive thermal properties. The ceramic adhesive remained stable at 800 °C with only 6% weight loss, while the other two disintegrated before 600 °C. [ABSTRACT FROM AUTHOR]

Polymer composites containing poly (methyl methacrylate) (PMMA) and barium titanate (BaTiO3) were synthesized using the solution mixing method. The electrical conductivity of PMMA is 6 × 10−9 S/cm, and adding 2% fillers reduces to 5 × 10−9 S/cm. The melting point of PMMA is 373 °C, and adding 2% and 4% fillers increased it to 376 °C and 379 °C, respectively. The polymer chains become less mobile and block macromolecules on the filler surface. The modulus of elasticity and mechanical tensile stress of the polymer composites with a 5-wt% of BaTiO3 are 759.3 MPa and 75.6 MPa, respectively. The breakdown strength of PMMA is 203 KV and reduces with the addition of 5% filler to 144 KV. The values of Ec/Em evaluated using the Tsai-Pagano, Christensen-Waals, ROM, Mori-Tanaka, and Halpin-Tsai models underpredict the modulus compared to experimental Ec/Em values. Fourier spectroscopy confirmed the presence of Ti-O and BaTiO3 bonds in the polymer composite. Scanning electron microscope images reveal spherical aggregates of BaTiO3 coated with PMMA and an interparticle network. The dielectric constant of PMMA is 3 and increased with the addition of 2% and 4% fillers to 4 and 4.3, respectively. [ABSTRACT FROM AUTHOR]

The degradation of different flexible polyurethane foams for molded application after thermal aging were compared. A reference sample using traditional higher emission additives and four samples of different composition using low-emission additives were compared. For the modified samples volatile organic compound (VOC) and semi-volatile organic compound (FOG/SVOC) contents fell well below the benchmarking limits, which indicates that the selected low-emission additives are incorporated into the polymer chain. To examine different material properties and for evaluating changes due to increased temperature exposure for a prolonged period of time mechanical and acoustic tests were carried out before and after dry heat aging. It was found that two low emission samples exhibited superior sound absorption compared to the reference sample along with less significant change after aging in the acoustic properties. The compressive strength was lower than the reference as a result of lower product densities. However, the change in compressive strength after aging was less than 15% (with one exception), which is acceptable according to the standard requirements. Thermogravimetric analysis was also performed and revealed that no significant difference can be observed between the examined samples due to heat degradation, indicating that the modifications made to reduce VOC content did not adversely affect the foam’s resistance to thermal degradation. [ABSTRACT FROM AUTHOR]

Developing a hybrid phenomenological model for predicting the sound absorption coefficient of a pineapple leaf fibre/waste tea leaf fibre/glass fibre/epoxy-based natural fibre-reinforced hybrid composites is the predominant topic of this article. Phenomenological models excel at extrapolating characteristic impedance and wave number whereas empirical models require fewer inputs but overlook wave propagation in pores. Existing models apply only to single-fibre-reinforced composites, necessitating the creation of a hybrid model for hybrid composites. The developed hybrid Zwikker–Kosten and Johnson–Champoux–Allard model shows good agreement with experimental data across the frequency range, with standard deviations of 0.001–0.029 and percent deviations of 1.11%–11.43%. The overall noise reduction coefficient between the model and experiments is 0.31 vs. 0.30, with a 3.33% deviation. Furthermore, the application of alkali treatment increased the surface roughness which in turn, enhanced the sound absorption capabilities of these composites. The increased fibre roughness also amplified friction between fibres and sound waves, resulting in higher sound absorption coefficients. In addition, X-ray diffraction, thermal stability (thermogravimetric analysis and differential scanning calorimetry), and scanning electron microscopy examinations were performed on the designated composition (5% by weight of pineapple leaf fibre and 25% by weight of waste tea leaf fibre) of the pineapple leaf fibre/waste tea leaf fibre/glass fibre/epoxy-based natural fibre-reinforced hybrid composite. [ABSTRACT FROM AUTHOR]

This study aims to develop alkyd-aldehyde and alkyd-ketone blends by modification of waste poly(ethylene terephthalate) (PET) based alkyd resin with urea-aldehyde (UA) and cyclohexanone formaldehyde (CHF) resins for use in coating applications. PET flakes were depolymerized by simultaneous hydrolysis-glycolysis reaction, and depolymerization product (DP) was used completely instead of the diol in the alkyd synthesis. For comparison, reference alkyds without PET were also synthesized. The effect of modifier resin at different ratios and the presence of DP on the coating and thermal properties of blend films were investigated. Medium-hard/hard and gloss/high gloss films with excellent adhesion and impact resistance were obtained from both blends. These films also demonstrated superior chemical and environmental resistance. Blends with CHF resin had better alkali resistance than those with UA resin. In PET-based blends, thermal resistance significantly increased with the addition of the CHF resin to the alkyd resin. Notably, the use of DP did not show a negative effect on the properties of alkyd resin and blend films. On the contrary, much better results were obtained than the alkyd resin alone. Overall, the modification with UA and CHF modifiers and using DP improved the coating properties of the blends. These blends are expected to be considered a sustainable and environmentally friendly alternative for designing versatile coatings for various applications.

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.

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.

The ash content of rubber was determined by thermogravimetric analysis (TGA) and the effects of sample amount, sample representativeness, heating rate, combustion temperature and combustion atmosphere on the test results were studied and the repeatability and reproducibility of the method were determined. The results showed that the optimal conditions of TGA were sample mass between 10 mg and 20 mg, heating rate of 20 ℃/min or 30 ℃/min, combustion temperature for raw rubber and compounded rubber (or vulcanized rubber) of 550 ℃ and 650 ℃, respectively. The repeatability and reproducibility of TGA were all good. When ash mass fraction of 4 types of different rubbers were from 0.29% to 5.12%, the repeatability within laboratory was from 0.110% to 0.303%, and the reproducibility between laboratories was from 0.283% to 0.676%.

Abstract Simple physico-chemical techniques can be used to evaluate the composition, structure, and characteristics of plant seeds to determine their viability, quality, and possible uses in agriculture. Advanced analytical techniques, including thermo gravimetric analysis (TGA), electron paramagnetic resonance (EPR), and high-pressure liquid chromatography (HPLC), provide completely new insights and more precise information. They can be integrated to build up seed quality profiles, with great advantage to assess water content, organic compounds, and inorganic metals without the need to carry out many extraction procedures, as requested by more conventional methods. In this study, seed lots from three different plant species such as Triticum turgidum L. subsp. durum (wheat), Trigonella foenum graecum L. (trigonella or fenugreek), and Atriplex halimus L. (saltbush or sea orach) have been used to test the potential of TGA, EPR, and HPLC to discriminate between seed-specific features. A key finding of this study is that HPLC is essential in Principal Component Analysis (PCA) because various seeds (from the same species or other species) may contain compounds with varying polarity groups. The reported data confirm the efficacy of this approach. These data, fully available for other users, are coherently constructed and provide a proof of concept for future seed quality control studies.

Abstract The objective of this research is to address the rut problems in asphalt pavements and to resist the permanent plastic deformation with the increasing heavy traffic loads. In this paper, a new type materials of high modulus asphalt was developed by incorporating styrene–butadiene–styrene (SBS) and zinc oxide nanoparticles (nano ZnO) with an (EME)-type high modulus modifier, guided by the synergistic effects and the preparation methods of High-speed shear. The basic road performance, mechanical response and thermal stability of the new high modulus asphalt materials were analysed through basic physical indicator tests, dynamic shear rheometer tests, thermogravimetric analysis (TGA), the time–temperature superposition principle, the Refutas model, and the Christensen-Andersen-Marasteanu model. The optimal results demonstrate that the optimal blend ratio of the developed asphalt is 12% EME/8% SBS/1.5% ZnO. Under this composition, the road performance indicator values of softening point, penetration and ductility of the modified asphalt met the standard requirements. The dynamic shear rheometer tests demonstrates that the inclusion of SBS and nano ZnO considerably enhanced the shear resistance and recovery deformation capacity of EME, effectively improving the high-temperature deformation resistance of asphalt. Furthermore,the Refutas and the Christensen-Andersen-Marasteanu model fitting results showed that adding SBS and nano ZnO considerably improved the temperature sensitivity of the EME types high modulus modified asphalt and exhibiting low frequency sensitivity. Compared to PR Module-type high modulus modifier(PRM),TGA reveals that the maximum thermal weight loss of EME-SBS-ZnO decreased by 3.5441%, indicating better thermal stability and the major character of SBS,EME and asphalt is physical reaction. Moreover, EME-nano ZnO-SBS high modulus asphalt at 64 °C shows Jnr-diff = 9.5% and passes the "E" extreme traffic grade. Additionally, its cost is 4.67% lower than that of the PRM high modulus modified asphalt, presenting considerable economic benefits.

The degradation of different flexible polyurethane foams for molded application after thermal aging were compared. A reference sample using traditional higher emission additives and four samples of different composition using low-emission additives were compared. For the modified samples volatile organic compound (VOC) and semi-volatile organic compound (FOG/SVOC) contents fell well below the benchmarking limits, which indicates that the selected low-emission additives are incorporated into the polymer chain. To examine different material properties and for evaluating changes due to increased temperature exposure for a prolonged period of time mechanical and acoustic tests were carried out before and after dry heat aging. It was found that two low emission samples exhibited superior sound absorption compared to the reference sample along with less significant change after aging in the acoustic properties. The compressive strength was lower than the reference as a result of lower product densities. However, the change in compressive strength after aging was less than 15% (with one exception), which is acceptable according to the standard requirements. Thermogravimetric analysis was also performed and revealed that no significant difference can be observed between the examined samples due to heat degradation, indicating that the modifications made to reduce VOC content did not adversely affect the foam’s resistance to thermal degradation.

Abstract Briquettes made from carbonized agricultural residues present sustainable material alternatives to wood charcoal and firewood for commercial and industrial applications. However, these briquettes are plagued by property weaknesses including low drop strength and thermal efficiency. Therefore, this study focuses on enhancing the physical, mechanical and thermal properties of composite briquettes produced from carbonized banana peels and waste glass. Composite briquettes comprised of banana peels biochar and waste glass powder (0%, 5%, 10%, 20%, 30%, 40%, and 50%) were developed, characterized, and evaluated using thermo-gravimetric analysis and bomb calorimetry to determine thermo-physical properties and higher heating values, respectively. The thermal efficiency and emissions (CO, CO2, and PM2.5) were assessed using the water boiling test and an emissions monitoring system. Proximate analysis revealed that moisture content, volatile matter, fixed carbon, and ash content of the developed briquettes ranged from 2.5 to 9.7%, 19.2 to 37.2%, 28.7 to 55.6%, and 7.2 to 44.9%, respectively. Drop strength for the briquettes was 84% without waste glass in the composite, increasing to 94–98% with waste glass included in the composite matrix. Higher heating values ranged from 20.1 to 35.8 MJ/kg. Thermal efficiency rose from 22% with no waste glass powder to 40% with 50% waste glass powder addition, while CO and CO2 emissions decreased from 41 to 11 ppm; and 50 to 15 ppm, respectively. PM2.5 remained constant across all banana peel biochar waste glass composites. Notably, even a modest 10% waste glass composition significantly improved drop strength and thermal efficiency, but higher waste glass percentages correlated with elevated ash values and reduced higher heating values. Therefore, the developed composite briquettes can be used in commercial and industrial applications including in some industrial boilers.

Thermal decomposition of hematite plays an important role during pelletization and the iron fine‐based smelting processes such as HIsarna and flash shaft smelter. The temperature at which pure hematite decomposition occurs depends on the partial pressure of oxygen in the gaseous atmosphere. In the air, that is, at po2 = 0.21, the hematite decomposes at 1386 °C. In the present work, for an ore of a given composition, the effect of gangue on the thermal decomposition of hematite is experimentally determined using thermogravimetric analysis (TGA). A decomposition temperature of 1320 °C is found in the platinum crucible after analyzing the TGA curve. Thermodynamic calculations have been carried out using FactSage8.1 to investigate the effect of gangue on the stability of hematite. Thermodynamics calculations confirm that the hematite present in the ore decomposes at a lower temperature with the increase in the gangue content. Additionally, if gangue content can affect the temperature at which dissociation of hematite occurs, it is expected that the crucible material can also affect the dissociation. Interestingly most of the reported TGA experiments are performed either in alumina crucibles or it was not reported in the literature. Therefore, the effect of crucible materials, namely alumina and platinum, is also investigated. [ABSTRACT FROM AUTHOR]

The thermal decomposition modeling of starch granules (rice, maize, and potato) is investigated in this work. Thermogravimetric analysis (TGA) under nitrogen conditions and different heating rates is carried out. First, a model‐free analysis is carried out to determine the variability of the activation energy with the relative conversion. The results reveal that the sequence of activation energy is rice > maize > potato. In turn, the activation energy is positively correlated (ρ = 0.98) with the relative crystallinity determined by X‐ray diffraction (XRD) analysis. Then, a fractional‐order version of the Sestak–Berggren equation is used to model the starch thermal decomposition. A least‐squares approach is used to estimate the underlying parameters by fitting non‐isothermal TGA curves. The results show that the parameters depend on the heating rate, but more strongly on the XRD relative crystallinity. Overall, the results reported in this study indicate that fractional‐order kinetics models provide an accurate description of the starch thermal degradation, without the use of the traditional TGA heuristic methods used for parameter estimation. [ABSTRACT FROM AUTHOR]