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Abstract Three novel Schiff base polymers were synthesized by using the Schiff base monomer obtained using aldehyde containing boric acid and amines containing hydroxyl groups as the starting materials. The polymers were synthesized at the same temperature and using the same amount of oxidizing agent by the oxidative polycondensation method. The characterization of all polymers and monomers was achieved by using Fourier transform infrared spectroscopy (FT-IR), ultraviolet–visible spectroscopy (UV–vis), nuclear magnetic resonance spectroscopy (1H-NMR), liquid chromatography-mass spectrometry (LC–MS), gel permeation chromatography (GPC) and scanning electron microscopy (SEM). The thermal stability of these compounds was studied by employing thermogravimetric analysis (TGA), and thermodynamics parameters such as activation energy (Ea), enthalpy (∆H), entropy (∆S), and Gibbs free energy(∆G) for the decomposition process were calculated using the Flynn–Wall–Ozawa method.

Abstract 2,6-Di-tert-butyl-4-methylphenol (BHT) is an excellent antioxidant that is easily oxidized to 2,6-di-tert-butyl-4-hydroperoxyl-4-methyl-2,5-cyclohexadienone (BHTOOH). For the safety of BHT production and usage, it is meaningful to study the thermal stability and decomposition properties of BHT and BHTOOH. In this paper, the thermal decomposition properties of BHT and BHTOOH were compared by the mini closed pressure vessel test (MCPVT) and differential scanning calorimetry (DSC). Their kinetics of thermal decomposition were studied using thermogravimetric analysis (TGA). The thermal decomposition products of BHT and BHTOOH were analyzed by gas chromatography-mass spectrometry (GC–MS). The results show that there was no significant change in temperature pressure when BHT was warmed up under a nitrogen atmosphere, indicating that BHT was stable within 400 K. The thermal decomposition reaction of BHTOOH was rapid with an initial reaction temperature of 375.2 K. The initial exothermic temperature (Ti) and heat release (QDSC) of DSC were 384.9 K and 865.0 J g−1, respectively. The apparent activation energies (Ea) for the thermal decomposition reactions of BHT and BHTOOH calculated by the Kissinger method were 151.8 kJ mol−1 and 66.07 kJ mol−1, respectively. The main decomposition products of BHT were isobutene and 2-tert-butyl-4-methylphenol. The thermal decomposition products of BHTOOH included BHT, 2,6-di-tert-butyl-4-ethylphenol, 3,5-di-tert-butyl-4-hydroxybenzaldehyde, 4,4′-(1,2-ethanediyl) bis [2,6-bis (1,1-dimethylethyl) phenol, etc. Based on the thermal decomposition behavior and products, the reaction pathway has been described. These results indicate that BHT is a potential thermal hazard during production, storage and application. For the safety of the chemical industry, the oxidation of BHT should be avoided.

In the realm of crystal growth, the utilization of dopant materials plays a pivotal role in tailoring the properties of single crystals. This research explores the incorporation of natural dyes, specifically the pigment derived from the Pisolithus Arhizus fungus extract, as a dopant material in the growth process of Guanidinium Carbonate (GC) single crystals. Comparative analyses were carried out between the dye-doped crystals and their undoped counterparts, revealing significant enhancements in the growth period, optical properties, mechanical properties, thermal properties and second harmonic generation (SHG) efficiency of the dye-doped crystals. Structural characterizations, including single crystal and powder X-ray diffraction techniques, confirmed the crystalline nature of both undoped and dye-doped crystals. Fourier Transform Infrared (FTIR) analysis validated the existence of functional groups, while Energy Dispersive X-ray Analysis (EDAX) confirmed the presence of dye molecules within the crystal lattice. UV–Visible spectroscopy and microhardness studies revealed enhanced optical and mechanical characteristics in dye-doped crystals compared to undoped ones. Thermogravimetric and Differential Thermal analysis (TG-DTA) indicate improved thermal stability in dye-doped crystals. The non-linear optical characterization showed 1.73 times increase in SHG efficiency in dye-doped crystals compared to undoped GC crystals. Therefore, including dye molecules in the crystal lattice improved the optical, thermal, mechanical properties and SHG efficiency, making dye-doped crystals suitable candidates for various optical applications.

This work provides data on strategies for single GdSrFeO4 phase solid state synthesis. Earlier works have shown that under the solid-state synthesis conditions, the GdSrFeO4 preparation is hampered by the formation of non-target product: Gd2SrFe2O7. This work approach led to the solid-phase synthesis GdSrFeO4 scheme change. GdSrFeO4 was characterized by X-Ray, scanning electron microscopy/energy dispersive X-ray spectroscopy, dilatometry and complex thermal analysis methods. GdSrFeO4 is stable in the wide range of studied temperatures 40–1,400°C in air. The sintering start temperature was determined to be 985°C. GdSrFeO4 has a thermal expansion coefficient of 30 × 10−6 K−1. The thermal stability is excellent for further investigation and potential for application of the materials as SOFC, for example. The study of catalytic stability of the obtained GdSrFeO4 is to be a subject of future work as well.

This study investigates the pyrolytic decomposition of apple and potato peel waste using thermogravimetric analysis (TGA). In addition, using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS), the influence of pyrolysis temperature on the physicochemical characteristics and structural properties of biochar was studied. The degradation of biomass samples was studied between 25 °C and 800 °C. Although apple and potato peel decomposition present similar thermogravimetric profiles, there are some differences that can be evidenced from DTG curves. Potato peel showed one degradation peak in the range 205–375 °C with 50% weight loss; meanwhile, the apple peel exhibited two stages: one with a maximum at around 220 °C and about 38% weight loss caused by degradation of simple carbohydrates and a second peak between 280 °C and 380 °C with a maximum at 330 °C, having a weight loss of approximately 24%, attributed to cellulose degradation. To gain more insight into the phenomena involved in biomass conversion, the kinetics of the reaction were analyzed using thermal data collected in non-isothermal conditions with a constant heating rate of 5, 10, 20, or 30 °C /min. The kinetic analysis for each decomposed biomass (apple and potato) was carried out based on single-step and multi-step type techniques by combining the Arrhenius form of the decomposition rate constant with the mass action law. The multi-step approaches provided further insight into the degradation mechanisms for the whole range of the decomposition temperatures. The effect of temperature on biomass waste structure showed that the surface morphologies and surface functional groups of both samples are influenced by the pyrolysis temperature. A higher pyrolysis temperature of 800 °C results in the disappearance of the bands characteristic of the hydroxyl, aliphatic, ether, and ester functional groups, characteristic of a porous surface with increased adsorption capacity. Therefore, this study concludes that biomass waste samples (apple and potato) can produce high yields of biochar and are a potential ecological basis for a sustainable approach. The preliminary adsorption tests show a reasonably good nitrate removal capacity for our biochar samples.

Strontium titanate (STO) and its variants have emerged as leading materials in photocatalysis, particularly for degrading nitrogen oxides (NOx), due to their non-toxic nature, structural adaptability, and exceptional thermal stability. Although the one-pot sol-gel method leads to high-quality photocatalysts, areas remain for improvement. This study examines the impact of ethanol as a cosolvent in STO synthesis, focusing on optimizing the water-to-ethanol volume ratio. The findings reveal that a 1:3 ratio significantly enhances macropore formation and photocatalytic efficiency, achieving 42% NOx degradation under LED within three hours. Furthermore, incorporating 8.0 wt.% Ag into STO substantially improves visible light absorption and enables complete NOx elimination, thanks to enhanced charge separation and localized surface plasmon resonance. Even at high temperatures (1100 °C), the Ag-STO photocatalyst maintains partial activity, despite exceeding silver’s melting point. These results highlight the potential of STO-based materials for industrial applications, positioning them as a promising solution for effective NOx mitigation.

Betacyclodextrin (β-CD)-assisted extracts of green rooibos displayed elevated polyphenolic content and antioxidant activity compared with aqueous extracts. This study aimed to analyse the physicochemical properties of aqueous green rooibos and 15 Mm β-CD at 40 °C for 60 min. Sorption isotherms and colour (L*a*b*C*) were evaluated. Thermogravimetric analysis and Fourier transform infrared were conducted to verify encapsulation. Sorption isotherm studies revealed that β-CD reduced water uptake, resulting in a reduction in the monolayer value of GRE (7.90) to 6.40 for β-GRE. Betacyclodextrin contributed to increased lightness (L*) and decreased redness (a*) of green rooibos. However, storing extracts at varied water activity resulted in a reduction in L* and chroma (C*), with a higher reduction observed for GRE than β-GRE. Thermogravimetric analysis revealed that GRE degraded at 180 °C, followed by β-GRE at 260 °C and β-CD at 340–375 °C. Betacyclodextrin increased the thermal stability of green rooibos; as a result, β-GRE displayed a superposition of GRE and β-CD in its thermogram, confirming the formation of inclusion complexes. Fourier transform infrared spectra indicated the disappearance or shifting of characteristic peaks, with the formation of hydrogen bonds between GRE and β-CD at the 1255 cm−1 band depicting C–O stretching of carboxylic acid.

Pomace, a waste product, generates a huge problem in the fruit and vegetable industry. Numerous studies prove that pomace and fibre are valuable sources of many nutrients. Due to their properties, their popularity is growing in many industries. Water vapour isotherms and kinetics were determined for selected fruit fibre and pomace. The activity and water content, colour, apparent and bulk density, and material structure were also investigated. In addition, the thermal stability of the tested fibres and pomace was examined. Fibre and pomace from chokeberries, apples and currants were used in the research. The determined kinetic curves proved that apple fibre absorbed more water vapour. The isotherms were found to have a shape characteristic of type III sorption isotherms. The Guggenheim–Anderson–de Boer model (GAB) described experimental data for sorption isotherms well (taking an RMS value of less than 10% as a good fit of the model to the sorption data). Thermogravimetric analysis showed good thermal stability, and all analysed fruit fibre and pomace showed similar behaviour in the three main stages of weight loss. The results suggest that the analysed waste materials can be used for different applications, including flour replacements for food products or filling materials in edible packaging films.

Large-scale distillation is a challenge in many respects. Particularly difficult is the purification by distillation of a compound with limited thermal stability. This article describes various aspects of these difficulties with some possible solutions. Special emphasis is placed on the collaboration of different disciplines to find pragmatic solutions to these challenges. The purification of diketene in quantities of several 1000 ta–1 is an excellent example to illustrate the different requirements. Although the distillation of diketene has been carried out by several companies for many years, there are still some aspects that deserve special attention.

In this study, the effects of high-intensity ultrasound (HIU) treatment combined with hydrogen peroxide (H2O2) addition on the thermal stability of myofibrillar protein (MP)–stabilized emulsions in low-salt conditions were investigated. Results showed that compared to using either HIU or H2O2 treatment alone, HIU treatment combined with H2O2 was most effective in enhancing the physical stability of emulsions. Moreover, the emulsion stabilized by MPs co-treated with HIU and H2O2 exhibited the most uniform distribution, highest absolute zeta potential, and optimal rheological properties upon heating. This combination effect during heating was caused by the inhibition of disulfide bond cross-linking of myosin heads by H2O2 and the dissociation of filamentous myosin structures using the HIU treatment. In addition, the results of oxidative stability analysis indicated that the addition of H2O2 increased the content of oxidation products; however, the overall influence on the oxidative stability of emulsions was not significant. In conclusion, the combination of HIU and H2O2 treatment is a promising approach to suppress heat-induced MP aggregation and improve the thermal stability of corresponding emulsions.

The potential applications of epoxy-based solid polymer electrolytes are continually expanding because of their versatile characteristics. These characteristics include mechanical rigidity, nonvolatility, nonflammability, and electrochemical stability. However, it is worth noting that pure epoxy-based solid polymer electrolytes inherently exhibit lower ion transport capabilities when compared to traditional liquid electrolytes. Striking a balance between high mechanical integrity and superior ionic conductivity at room temperature poses a significant challenge. In light of this challenge, this review is dedicated to elucidating the fundamental concepts of epoxy-based solid polymer electrolytes. It will explore various preparation techniques, the incorporation of different nanomaterials into epoxy-based solid polymer electrolytes, and an evaluation of their multifunctional properties. This comprehensive evaluation will cover both mechanical and electrical properties with a specific focus on their potential applications in batteries and structural supercapacitors.

Encapsulating enzymes in a tailored scaffold is of great potential in industrial enzymatic catalysis, which can enhance the stability of enzymes thus expanding their applications. Metal–organic frameworks (MOFs) are emerging as promising candidates for enzyme encapsulation due to their precise pore structure, ease of synthesis and good biocompatibility. Despite the fact that enzymes encapsulated in MOFs can obtain enhanced stability, there has been little discussion about the thermal stability of enzyme-MOF composites in solid state under extremely high temperatures. Herein, we fabricated the enzyme-MOF composites, CALB-ZIF-8, via a convenient coprecipitation method in aqueous solution, which exhibited good thermal stability at 180 °C. It was found that the activity of CALB encapsulated in ZIF-8 retained nearly ~80% after heating for 10 min at 180 °C. A finite element method was applied to investigate the heat transfer process within a ZIF-8 model, indicating that the air filled in cavities of ZIF-8 played a significant role in hindering the heat transfer and this may be an important reason for the outstanding thermal stability of CALB-ZIF-8 at 180 °C, which paves a new path for expanding the industrial application of enzyme-MOF composites.

A new series of flexible polyamide (PA) aerogels was synthesized using terephthaloyl chloride (TPC), 2,2′-dimethylbenzidine (DMBZ) and cross-linked with an inexpensive, commercially available tri-isocyanate (Desmodur N3300A) at polymer concentrations of 6–8 wt.% total solids and repeating units, n, from 30 to 60. The cross-linked DMBZ-based polyamide aerogels obtained, after supercritically drying using liquid CO2, had shrinkages of 19–27% with densities ranging from 0.12 g/cm3 to 0.22 g/cm3, porosity and surface areas up to 91% and 309 m2/g, respectively, and modulus values ranging from 20.6 to 109 MPa. Evidence suggests that a higher flexibility could be achieved using DMBZ in the polyamide backbone with N3300A as a cross-linker, when compared to previously reported TPC-mPDA-BTC PA aerogels, N3300A-polyimide aerogels, and N3300-reinforced silica aerogels.

Colloidal quantum dots (CQDs) are valuable for their potential applications in optoelectronic devices. However, they are susceptible to thermal degradation during processing and while in use. Mitigating thermally induced sintering, which leads to absorption spectrum broadening and undesirable changes to thin film electrical properties, is necessary for the reliable design and manufacture of CQD-based optoelectronics. Here, low-temperature metal–oxide atomic layer deposition (ALD) was investigated as a method for mitigating sintering while preserving the optoelectronic properties of mercury telluride (HgTe) CQD films. ALD-coated films are subjected to temperatures up to 160 °C for up to 5 h and alumina (Al2O3) is found to be most effective at preserving the optical properties, demonstrating the feasibility of metal–oxide in-filling to protect against sintering. HgTe CQD film electrical properties were investigated before and after alumina ALD in-filling, which was found to increase the p-type doping and hole mobility of the films. The magnitude of these effects depended on the conditions used to prepare the HgTe CQDs. With further investigation into the interaction effects of CQD and ALD process factors, these results may be used to guide the design of CQD–ALD materials for their practical integration into useful optoelectronic devices.

In this paper, we present the synthesis, characterization and evaluation of antiproliferative activity for four compounds carrying the 4-amino-5-mercapto-1,2,4-triazol-3-yl scaffold. The synthesis of 1,n-bis-(4-amino-5-mercapto-1,2,4-triazol-3-yl) alkanes was carried out using as starting reagents the dihydrazides of oxalic, malonic, succinic and adipic acids, using mercaptoacetic acid dianion as a leaving group, by a one-pot synthesis method implemented in our research group for the synthesis of 3-substituted-5-mercapto-1,2,4-triazoles. The compounds were obtained with modest yields (12–60%) but with good purity and were characterized by elemental analysis, FTIR, 1H-NMR and 13C-NMR spectroscopy. Also, the stability of the synthesized bis-triazoles was investigated under controlled thermal stress in a dynamic oxidative atmosphere. The last part of the study consisted of biological activity evaluation, by evaluating the antiproliferative activity against the A375 line (human malignant melanoma), as well as on viability of the BJ fibroblast cell line, using MTT and LDH assays.

Although various degradable gel materials have been developed for temporary plugging in oil fields, they often degrade too quickly in high-temperature environments. To address this issue, an unstable crosslinker was synthesized to prepare a high-temperature degradable gel. This gel does not degrade excessively fast at high temperatures. Temperature and crosslinker concentration are the primary factors influencing gel degradation time, followed by monomer and initiator concentrations. Increased temperature and decreased crosslinker concentration both reduce degradation time, which can be adjusted within the range of 90–130 °C by varying the crosslinker concentration. The molecular structure and thermal stability of the degradable gel were analyzed using FTIR, 13C NMR, and TG. Furthermore, the viscoelastic properties, compressive performance, plugging performance, and core damage performance of the gel were evaluated. Within the test range of 0.1–1000 Pa, the storage modulus is higher than the loss modulus. The gel prepared at 130 °C exhibited a compressive stress of 0.25 MPa at 50% strain. The plugging pressure of the gel in sand-filled tubes with varying permeabilities (538.2–2794.1 mD) exceeded 15 MPa while maintaining a core damage rate below 5%. SEM analysis indicated that the degradation mechanism of the gel may involve the collapse of its three-dimensional network structure due to the hydrolysis of amide groups in the crosslinker. The viscosity of the degradation liquid was below 11 mPa·s, enabling it to be brought back to the surface with the formation fluid without the need for further breaking operations.

We analyzed the thermal stability of the BstHPr protein through the site-directed point mutation Lys62 replaced by Ala residue using molecular dynamics simulations at five different temperatures: 298, 333, 362, 400, and 450 K, for periods of 1 μs and in triplicate. The results from the mutant thermophilic BstHPrm protein were compared with those of the wild-type thermophilic BstHPr protein and the mesophilic BsHPr protein. Structural and molecular interaction analyses show that proteins lose stability as temperature increases. Mutant and wild-type proteins behave similarly up to 362 K. However, at 400 K the mutant protein shows greater structural instability, losing more buried hydrogen bonds and exposing more of its non-polar residues to the solvent. Therefore, in this study, we confirmed that the salt bridge network of the Glu3–Lys62–Glu36 triad, made up of the Glu3–Lys62 and Glu36–Lys62 ion pairs, provides thermal stability to the thermophilic BstHPr protein.

This study aims to enhance the optical and thermal properties of cesium-based perovskite nanocrystals (NCs) through surface passivation with organic sulfonate (or sulfonic acid) ligands. Four different phenylated ligands, including sodium β-styrenesulfonate (SbSS), sodium benzenesulfonate (SBS), sodium p-toluenesulfonate (SPTS), and 4-dodecylbenzenesulfonic acid (DBSA), were employed to modify blue-emitting CsPbBr1.5Cl1.5 perovskite NCs, resulting in improved size uniformity and surface functionalization. Transmission electron microscopy and X-ray photoelectron spectroscopy confirmed the successful anchoring of sulfonate or sulfonic acid ligands on the surface of perovskite NCs. Moreover, the photoluminescence quantum yield increased from 32% of the original perovskite NCs to 63% of the SPTS-modified ones due to effective surface passivation. Time-resolved photoluminescence decay measurements revealed extended PL lifetimes for ligand-modified NCs, indicative of reduced nonradiative recombination. Thermal stability studies demonstrated that the SPTS-modified NCs retained nearly 80% of the initial PL intensity when heated at 60 °C for 10 min, surpassing the performance of the original NCs. These findings emphasize the optical and thermal stability enhancement of cesium-based perovskite NCs through surface passivation with suitable sulfonate ligands.

Polymer-based coatings are widely used as a protective barrier to corrosion, but their performance is not sufficiently sustainable for industrial applications due to the formation of micropores and microcracks during solidification. Graphene is a promising reinforcing element acting as a filler for polymeric coatings. This study used 1–5 wt% graphene synthesized by the electrochemical exfoliation process as a reinforcing nanofiller to manufacture graphene-reinforced epoxy nanocomposite (GREN) coatings. Copper was used as a substrate material for coating with GREN by a bar coating method. GREN coatings were characterized by X-ray diffraction, Raman spectroscopy, FTIR spectroscopy, FESEM, and EDX. A comprehensive investigation was conducted on the various multi-physical properties of GREN coatings, including coating thickness, surface roughness, adhesiveness, surface wettability, water absorptivity, thermal stability, electrical conductivity, and anti-corrosion capabilities. The results exhibited that graphene fills micro-pores produced in epoxy during solidification. The surface roughness significantly decreased to 0.25 µm with the addition of 5 wt% graphene in pure epoxy. In addition, the adhesiveness, thermal stability, and electrical conductivity of GREN coatings increased with the increase in graphene content. The GREN coatings containing 3 wt% and 5 wt% graphene revealed hydrophobic surface showing 94° and 102° water contact angle, respectively. In the electrochemical analysis and immersion test in 3.5 % NaCl solution for 600 h, the GREN coatings showed higher corrosion resistance without compromising their electrical conductivity compared to the pure epoxy. Based on the results, GREN can be a promising coating material for aerospace, mining, and electronic packaging applications. Apart from this, the results of this work will explore the new significance in industry, where multi-physical properties from a single nanocomposite coating are crucial.

The growing demand for lithium‐ion batteries to power electric vehicles and other energy‐dense devices continues to fuel the need for cathodes of increasingly higher nickel in cathodes. The relentless pursuit of high Ni content, however, raises concerns on compromising cell lifetime and safety, especially under high‐voltage operation. Alternative to the traditional design of uniform or core–shell composition, we report a rational control of local stoichiometry in high‐Ni cathodes, enabling their high thermal and cycling stabilities—up to 258 °C at the fully charged state and 91.4% capacity retention for 100 cycles between 2.7 and 4.4 V. Multimodal synchrotron X‐ray characterization unveils the heterostructure of secondary particles, featuring a high‐Ni core (LiNi0.90Mn0.05Co0.05O2) covered by a thin Ni‐gradient layer that remains stable over prolonged cycling due to suppressed oxygen release and structural deterioration. This work underlines, the intricate interplay between local stoichiometry and redox reactions in stabilizing high‐Ni cathodes for high‐voltage operation while ensuring safety.

To prepare an innovative thermal stabilizer for polyvinyl chloride (PVC), the micro-nano powders of alkoxyl tin (RxOSn) were synthesized via a solid phase reaction at room temperature, using the surfactant sodium benzene sulfonate (SBS) as a catalyst. Theoretical calculation of deprotonation reaction energy of monobasic alcohol and tin chloride was performed with the framework of DFT, and their structures were characterized by XRD, SEM, FT-IR, XPS, and its surface wetting performance was carried out by contact angle (CA). Meanwhile, the multi-stage thermal stability of PVC with 10% RxOSn sample, and the role of alkyl groups (Rx, x = 2 ∼ 5) in the RxOSn/PVC were investigated. The results show that the RxOSn samples exhibit a microstructure akin to the rutile of SnO2. Multi-stage kinetic studies of exothermic reactions has confirmed that the alkoxyl wetting performance of stabilizers becomes a determining factor, while the variation in activation energy (Ea) values seems to be mainly influenced by the Rx alkyl groups in the RxOSn samples. Besides, the differences in the lattice parameter a of RxOSn were validated to have a certain impact on the stabilizing effect of PVC, and the Ea of PVC degradation is closely related to the relative value of exposed crystal surfaces (D(110)/D(101)). This series of materials is easily synthesized and can effectively enhance the thermal stability of PVC, offering a wide range of potential applications.

The manufacture of vibration damping material from natural rubber (NR) required an increase in dynamic properties, thermal stability, and resistance to heat. Using the Carbon Black N990 as a filler in NR vulcanizates can potentially increase on these properties. This research aims to study the effect of using Carbon Black N990 on dynamic properties, thermal stability, and aging resistance to heat in NR vulcanizates. The dynamic properties of NR vulcanizates were determined by Rubber Process Analyzer (RPA), while the thermal stability properties were studied by TGA, and heat resistance was determined by the thermal aging test. The RPA test results showed that adding 50 phr Carbon Black N990 in the NR compound could increase the value of the complex shear modulus to 65%. Furthermore, the results of the TGA test showed that the thermal stability properties of unfilled NR vulcanizates were better than that of NR vulcanizates containing Carbon Black N990. Unfilled NR vulcanizates were heat stable up to 353oC, while NR vulcanizates containing 15, 30, and 50 parts per hundred rubber (phr) Carbon Black N990, respectively, were heat stable up to 348.1oC, 348oC, and 349oC. Based on the requirements of ISO 4632-1, it showed that the NR compound containing Carbon Black N990 has good heat resistance properties. The NR compound formula contains 30 phr Carbon Black N990 showing good dynamic properties and heat resistance in accordance with EN 15129 requirements so that it has the potential to be used as a vibration damping material for earthquake-resistant structures.

Nanocrystalline carbonyl iron (CI) particles are promising microwave absorbents at elevated temperature, whereas their excessive grain boundary energy leads to the growth of nanograins and a deterioration in permeability. In this work, we report a strategy to enhance the thermal stability of the grains and microwave absorption of CI particles by doping a SiBaFe alloy. Grain growth was effectively inhibited by the pinning effect of SiBaFe alloy nanoparticles at the grain boundaries. After heat treatment at 600 °C, the grain size of CI particles increased from ~10 nm to 85.1 nm, while that of CI/SiBaFe particles was only 32.0 nm; with the temperature rising to 700 °C, the grain size of CI particles sharply increased to 158.1 nm, while that of CI/SiBaFe particles was only 40.8 nm. Excellent stability in saturation magnetization and microwave absorption was also achieved in CI/SiBaFe particles. After heat treatment at 600 °C, the flaky CI/SiBaFe particles exhibited reflection loss below −10 dB over 7.01~10.11 GHz and a minimum of −14.92 dB when the thickness of their paraffin-based composite was 1.5 mm. We provided a low-cost and efficient kinetic strategy to stabilize the grain size in nanoscale and microwave absorption for nanocrystalline magnetic absorbents working at elevated temperature.

Conventional hole transport layer (HTL) Spiro-OMeTAD requires the addition of hygroscopic dopants due to its low conductivity and hole mobility, resulting in a high preparation cost and poor device stability. Cuprous thiocyanate (CuSCN) is a cost-effective alternative with a suitable energy structure and high hole mobility. However, CuSCN-based perovskite solar cells (PSCs) are affected by environmental factors, and the solvents of an HTL can potentially corrode the perovskite layer. In this study, a Co3O4/CuSCN/Co3O4 sandwich structure was proposed as an HTL for inorganic Cs2PbI2Cl2/CsPbI2.5Br0.5 PSCs to address these issues. The Co3O4 layers can serve as buffer and encapsulation layers, protecting the perovskite layer from solvent-induced corrosion and enhancing hole mobility at the interface. Based on this sandwich structure, the photovoltaic performances of the Cs2PbI2Cl2/CsPbI2.5Br0.5 PSCs are significantly improved, with the power conversion efficiency (PCE) increasing from 9.87% (without Co3O4) to 11.06%. Furthermore, the thermal stability of the devices is also significantly enhanced, retaining 80% of its initial PCE after 40 h of continuous aging at 60 °C. These results indicate that the Co3O4/CuSCN/Co3O4 sandwich structure can effectively mitigate the corrosion of the perovskite layer by solvents of an HTL and significantly improves the photovoltaic performance and thermal stability of devices.

Samaria-doped ceria (SDC) overlayers were deposited on Ag cathodes by sputtering. The SDC sputtering time was varied to investigate the properties of the Ag–SDC overlayer cathode-coated fuel cells depending on the thickness of the SDC overlayers. Among the fabricated fuel cells, Ag with a 10-nm-thick SDC overlayer (Ag-SDC10) cathode-coated fuel cell exhibited the highest peak power density of 6.587 mW/cm2 at 450 °C, showing higher performance than a pristine Pt-coated fuel cell. Moreover, electrochemical impedance spectroscopy revealed that the Ag-SDC10 cathode-coated fuel cell significantly mitigated polarization loss originating from enhanced oxygen reduction reaction kinetics compared to the pristine Ag-coated fuel cell.

All-inorganic CsPbI3–xBrx perovskite solar cells (PSCs) are advantageous in terms of high thermal stability, while its efficiency lags behind those of organic-inorganic hybrid perovskite counterparts. Defect passivations have been extensively applied for enhancing efficiency of all-inorganic PSCs, which are mainly based on univocal defect passivation of perovskite layer. Herein, we incorporated a bis-dimethylamino-functionalized fullerene derivative (abbreviated as PCBDMAM) as an interlayer between ZnO electron transport layer (ETL) and all-inorganic CsPbI2.25Br0.75 perovskite layer, accomplishing synchronous defect passivations of both layers and consequently dramatic enhancements of efficiency and thermal stability of PSC devices. Upon spin-coating PCBDMAM onto ZnO ETL, the surface defects of ZnO especially oxygen vacancies can be effectively passivated due to the formation of Zn−N ionic bonds. In addition, PCBDMAM incorporation affords effective passivation of PbI and IPb antisite defects within the atop perovskite layer as well via coordination bonding with Pb2+. As a result, the regular-structure planar CsPbI2.25Br0.75 PSC device delivers a champion power conversion efficiency (PCE) of 17.04%, which surpasses that of the control device (15.44%). Moreover, the PCBDMAM-incorporated PSC device maintains ~ 80% of its initial PCE after 600 h heating at 85 °C hot plate in N2 atmosphere, whereas PCE of the control device degrades rapidly to ~ 62% after 460 h heating under identical conditions. Hence, PCBDMAM incorporation benefited dramatic improvement of the thermal stability of PSC device.

Objectives. The study aimed to develop new effective heat stabilizers based on glycerol esters of monocarboxylic acids for industrial chlorinated paraffins and to select of the optimal ratio of active ingredients in the stabilizing composition in order to provide the maximum thermostabilizing effect.Methods. The thermostabilizing effect of the studied samples on chlorinated paraffins was evaluated according to the standard method for determining the thermal stability of liquid chlorinated paraffins in terms of the mass fraction of split off hydrogen chloride. Quantitative and qualitative analysis of the obtained mixtures of monocarboxylic acid glycerides was carried out using chromato-mass spectrometry.Results. Glycerides of monocarboxylic acids (oleic, octanoic, hexanoic, and propionic acids) were obtained and identified, and the compositions of the resulting mixtures of mono-, di- and triesters were determined. The stabilizing effect of the obtained mixtures of glycerides of monocarboxylic acids in the amount of 0.5–2.0 wt parts per 100 wt parts of unstabilized industrial chlorinated paraffin CP-30 was determined. The combined use of glycerides of monocarboxylic acids with calcium-containing compounds as a complex stabilizer with a molar ratio of esters/Ca 0.93–0.86/0.07–0.14, respectively, was investigated. Chloroparaffin CP-470, stabilized by the developed complex stabilizer, was successfully used in a polyvinyl chloride composition for cable compound of the brand OM-40.Conclusions. A proposed variant of a complex stabilizer for chlorinated paraffins based on Russian raw materials for import substitution will expand the range of effective stabilizers for organochlorine substances. Glycerides of monocarboxylic acids are shown to exhibit a thermostabilizing effect on industrial chlorinated paraffins. The relationship between the length of the hydrocarbon substituent of the carboxylic acid in the ester and the thermostabilizing effect is obtained. With an increase in the number of carbon atoms in the hydrocarbon substituent of the carboxylic acid, the heat-stabilizing ability decreases. The minimum sufficient concentration of glycerides of carboxylic acids was 0.05 ± 0.005 mol/kg, above which no increase in the thermostabilizing effect on chloroparaffin was observed. A synergistic ratio of the components of the stabilizing mixture in terms of thermal stability—glycerides of monocarboxylic acids/calcium-containing compounds—was found equal to 0.85–0.9/0.15–0.1.

Butylated hydroxytoluene (BHT) is an excellent antioxidant widely used in food, polymer materials, and other fields. In order to understand the hazards of BHT, it is necessary to study its thermal stability, oxidation properties, and reaction products. This paper investigated BHT's oxidation characteristics and products using a mini-closed pressure vessel test (MCPVT), UV radiation reaction method, iodometric method, and gas chromatography-mass spectrometry (GC–MS). The MCPVT results showed that no chemical reaction of BHT was observed under a nitrogen atmosphere even when the temperature was increased to 450 K, which indicated that it was stable. However, BHT was readily oxidized under an oxygen atmosphere with an initial oxidation temperature of 332 K. Notably, oxidation reactions can occur as low as 293 K under 365 nm UV radiations in the atmosphere. The kinetics of the initial oxidation of BHT was investigated. The kinetics of the reaction of BHT in MCPVT was a second-order reaction with the kinetic equation lnk = -1.2194 × 104(1/T) + 21.4. And Ea = 101.4 kJ mol−1. The difference is that a pseudo-first-order reaction was shown under UV radiation, with a linear relationship between the apparent activation energy and the logarithm of the light intensity (I): Ea = -1.878 lnI + 74.56, the apparent activation energy was significantly reduced compared to the former, indicating that UV light has a great effect on the oxidation of BHT. The peroxide value of the BHT oxidation product in MCPVT was determined with the iodometric method. When the reaction was carried out at 358 K for 8 h, the peroxide value of BHT was 3.2 mmol kg−1. The main oxidation products of BHT were identified with GC–MS, such as 2, 6-di-tert-butyl-p-benzoquinone, 1-(2, 4, 6-trihydroxyphenyl) butanone, 3, 5-di-tert-butyl- 4-hydroxybenzaldehyde, 3, 5-di-tert-butyl-4-hydroxyacetophenone. Based on these oxidation products, the oxidation pathway of BHT was described. In conclusion, the oxidation characteristics of BHT were studied in detail with MCPVT, and a method for evaluating thermal stability was developed. UV radiation made BHT more susceptible to oxidation reactions. These data provided a reference for BHT's storage, transportation, and safety evaluation.

One of the significant problems of drilling with water-based muds in oil and gas wells is the instability in the Shale Formations. Conventional additives cannot plug nanometer-sized pore throats of Shale. Today, Nanotechnology is used to improve the performance of water-based muds. Adding some Nanoparticles with unique properties to drilling fluids has remarkably improved the mud’s properties. Therefore, this study synthesized Amorphous Mesoporous Silica Nanoparticles (AMSN) with heightened purity and suitable Special Surface Area (SSA) using the sol–gel method. Then AMSN was employed in an eco-friendly water-based mud to investigate the effect on rheological properties, filtration, thermal stability, and Shale recovery.Several analyses were conducted on AMSN synthesized by TEM, FESEM, EDX, DLS, XRF, XRD, BJH, and BET. According to the results, AMSN has an amorphous phase, and its purity, SSA, and total pore volume stand at 98.99%, 226.13 (m2.g−1), and 1.0539 (m3.g−1). Under two conditions, the AMSN was incorporated into the water-based drilling fluid at four concentrations: 0.1, 0.5, 1, and 2% W/W. The primary condition is Before Hot Rolling (BHR), conducted at a temperature of 43.3 °C. A second trial was conducted after hot rolling (AHR) at simulated downhole temperatures of 121.1 °C and 148.8 °C, respectively. In both conditions, the results indicate that the ideal concentration of AMSN is 0.1% by weight and improves the rheological properties, thermal stability, and Shale recovery. Comparatively to base mud, an optimal concentration of AMSN can increase apparent viscosity by 12.5% and reduce fluid loss by 55% in AHR conditions.

Electrostatic accumulation is associated with almost all powder-conveying processes which could bring about electrostatic discharges. In most cases of industrial accidents, electrostatic discharge is proven to be the primary source of ignition and explosion. Herein, a surface modification process of polyaniline (PANI) is proposed to construct highly exothermic special powders, namely, HMX@PANI energetic composites, with low charge accumulation for improving powder electrostatic safety. Pure HMX are encapsulated within the PANI-conductive polymer layer through simple hydrogen bonding. Simulation results demonstrate that the forming process of HMX/aniline structure is a spontaneously thermodynamical process. The resultant inclusion complex exhibits excellent thermal stability, remarkable compatibility and intensive heat release. Importantly, PANI possesses superior electrostatic mobility characteristics because of the π-conjugated ligand, which can significantly reduce the accumulated charges on the surface of energetic powders. Moreover, the modified explosive has a narrower energy gap, which will improve the electron transition by reducing the energy barrier. The electrostatic accumulation test demonstrates that HMX@PANI composites possess a trace electrostatic accumulation of 34 nC/kg, which is two orders of magnitude lower than that of pure HMX (−6600 nC/kg) and might indicate a higher electrostatic safety. In conclusion, this surface modification process shows great promise for potential applications and could be extensively used in the establishment of high electrostatic safety for special powders.

The thermal stability of bovine serum albumin (BSA) in Tris buffer, as well as the effect of sinapic acid (SA) on protein conformation were investigated via calorimetric (differential scanning microcalorimetry—μDSC), spectroscopic (dynamic light scattering—DLS; circular dichroism—CD), and molecular docking approaches. μDSC data revealed both the denaturation (endotherm) and aggregation (exotherm) of the protein, demonstrating the dual effect of SA on protein thermal stability. With an increase in ligand concentration, (i) protein denaturation shifts to a higher temperature (indicating native form stabilization), while (ii) the aggregation process shifts to a lower temperature (indicating enhanced reactivity of the denatured form). The stabilization effect of SA on the native structure of the protein was supported by CD results. High temperature (338 K) incubation induced protein unfolding and aggregation, and increasing the concentration of SA altered the size distribution of the protein population, as DLS measurements demonstrated. Complementary information offered by molecular docking allowed for the assessment of the ligand binding within the Sudlow’s site I of the protein. The deeper insight into the SA–BSA interaction offered by the present study may serve in the clarification of ligand pharmacokinetics and pharmacodynamics, thus opening paths for future research and therapeutic applications.

Graphene is a fundamental unit of carbon materials and, thus, primary sp2-bonded carbon material. Graphene is, however, easily broken macroscopically despite high mechanical strength, although its natural degradation has rarely been considered. In this work, we evaluate the natural degradation of two-layer graphene in vacuo, in low-humidity air, and in high-humidity air at 300, 400, 450, and 500 K. Over 1000 days of degradation at 300 K, the graphene structure was highly maintained in vacuo, whereas the layer number of graphene tended to decrease in high- and low-humidity air. Water was slightly reacted/chemisorbed on graphene to form surface oxygen groups at 300 K. At 450 and 500 K, graphene was moderately volatilized in vacuo and was obviously oxidized in high- and low-humidity air. Surprisingly, the oxidation of graphene was more suppressed in the high-humidity air than in the low-humidity air, indicating that water worked as an anti-oxidizer of graphene by preventing the chemisorption of oxygen on the graphene surface.

Perovskite solar cells (PSCs) have been significantly improved by utilizing an inorganic hole-transporting layer (HTL), such as nickel oxide. Despite the promising properties, there are still limitations due to defects. Recently, research on self-assembled monolayers (SAMs) is being actively conducted, which shows promise in reducing defects and enhancing device performance. In this study, we successfully engineered a p-i-n perovskite solar cell structure utilizing HC-A1 and HC-A4 molecules. These SAM molecules were found to enhance the grain morphology and uniformity of the perovskite film, which are critical factors in determining optical properties and device performance. Notably, HC-A4 demonstrated superior performance due to its distinct hydrophilic properties with a contact angle of 50.3°, attributable to its unique functional groups. Overall, the HC-A4-applied film exhibited efficient carrier extraction properties, attaining a carrier lifetime of 117.33 ns. Furthermore, HC-A4 contributed to superior device performance, achieving the highest device efficiency of 20% and demonstrating outstanding thermal stability over 300 h.

Cathode active materials and conductive additives for thermal batteries operating at high temperatures have attracted research interest, with a particular focus on compounds offering high thermal stability. Recently, FeF3 has been proposed as a candidate for high-voltage cathode materials; however, its commercialization is hindered by its low conductivity. In this study, conductive additives, such as Ni-coated carbon composites (multi-walled carbon nanotubes (MWCNTs) and carbon black (CB)), were utilized to enhance the thermal stability and conductivity of FeF3. The incorporation of metal–carbon conductive additives in the FeF3 composite increased the thermal stability by more than 10 wt.% and ensured high capacity upon conductivity enhancement. The FeF3@Ni/MWCB 15 wt.% composite containing 30 wt.% Ni exhibited a discharge capacity of ∼86% of the theoretical capacity of 712 mAh/g. The use of Ni-coated carbon-based conductive additives will allow the application of FeF3 as an effective high-temperature cathode material for thermal batteries.

The enzyme PAL (phenylalanine ammonia lyase) mediates the key entry point to the general phenylpropanoid pathway, which is involved in the lignification process and in the formation of a myriad of secondary compounds in plants that show a variety of biological activities. Soluble fractions containing PAL extracted from Piper and Peperomia species had the optimal catalytic activity analyzed by statistical design model. This analysis revealed that the best conversion of L-phenylalanine to trans-cinnamic acid was pH 9.3 and 58 °C after 25 h, corroborating interesting thermal stability. Additionally, the pre-purification of PAL using ammonium sulfate precipitation (25-55%) increased its specific activity, approximately 133% in P. aduncum and more than 900% in P. crassinervium. The content of lignin was higher for P. tuberculatum (25.71%), while only a small amount of lignin was observed in Peperomia blanda (11.95%). It is interesting to note that Peperomia plants are succulent and without significant amounts of lignin. However, the phenylpropanoid biosynthetic pathway is apparently addressed to produce predominantly tetrahydrofuran lignans with biological interest.

Abstract The use of deuterium are critical for promoting the fundamental understanding of aggregate materials and their new functions. Particularly, the solution structure of conjugated polymers can be hardly resolved without deuteration. However, studies about the isotopic effects of casting solvents on the aggregated structures of photovoltaic polymers and their bulk‐heterojunction blends are deficient. Here, the impact of deuterated solvents on the thermal behavior, aggregated structures, and device performance of photovoltaic polymers is clearly delineated for the first time by multiple techniques. The enhanced π‐π stacking order of photovoltaic polymers is highly relevant to their relatively poor miscibility with deuterated solvents. Benefiting from higher crystallinity and optimized morphology of deuterated solvents processed films, the devices are able to achieve better efficiency and notable improvement in thermal stability. Our results highlight the isotopic effects of solvents on the aggregated structure of conjugated polymer systems and reveal the potential of innovative approaches to fabricate thermally stable high‐efficiency solar cells.

The p53 protein is a transcriptional regulatory factor and many of its functions require that it forms a tetrameric structure. Although the tetramerization domain of mammalian p53 proteins (p53TD) share significant sequence similarities, it was recently shown that the tree shrew p53TD is considerably more thermostable than the human p53TD. To determine whether other mammalian species display differences in this domain, we used biophysical, functional, and structural studies to compare the properties of the p53TDs from six mammalian model organisms (human, tree shrew, guinea pig, Chinese hamster, sheep, and opossum). The results indicate that the p53TD from the opossum and tree shrew are significantly more stable than the human p53TD, and there is a correlation between the thermostability of the p53TDs and their ability to activate transcription. Structural analysis of the tree shrew and opossum p53TDs indicated that amino acid substitutions within two distinct regions of their p53TDs can dramatically alter hydrophobic packing of the tetramer, and in particular substitutions at positions corresponding to F341 and Q354 of the human p53TD. Together, the results suggest that subtle changes in the sequence of the p53TD can dramatically alter the stability, and potentially lead to important changes in the functional activity, of the p53 protein.

In this paper, an equimolar blend of bisphenol A dipropargyl ether and cyanate ester was selected to study the effect of different catalysts on the curing reaction of a bisphenol A dipropargyl ether and cyanate ester blended resin system, and the thermal stability and mechanical properties of the catalytically cured blended resin system were investigated. Acetylacetone salts of transition metals and dibutyl ditin laurate reduced the curing temperature of bisphenol AF-type di cyanate ester, and copper acetylacetonate at a mass fraction of 0.3% significantly reduced the curing temperature of bisphenol AF-type di cyanate ester to less than 473 K. Bisphenol A dipropargyl ether pr-polymerized and equimolarly blended with bisphenol A di cyanate ester and bisphenol E-type di cyanate ester also cured below 473 K under the same conditions. Among the cured compounds of the blended resins of bisphenol A dipropargyl ether with bisphenol AF-type di cyanate ester, bisphenol A-type di cyanate ester and bisphenol E-type di cyanate ester, the blended resins of bisphenol A-type di cyanate ester and bisphenol E-type di cyanate ester have better overall performance. The residual rate of 873 K in air was 38%, and the flexural strength, flexural modulus, and impact strength were 129.4 MPa, 4.3 GPa, and 27.3 kJ·m−2, respectively. This kind of blended resin is expected to be used in the liquid oxygen storage tanks of rockets.

The objective of this work was to improve the thermal stability, flame resistance, and surface properties of black poplar (Populus nigra L.) wood via different impregnation methods. The impregnation methods were employed through two distinct modalities: vacuum impregnation and immersion impregnation. Here, poplar wood was impregnated with calcium oxide solutions (1%, 3% and 5%). Fourier-transform infrared spectroscopic analysis revealed a shift in the typical peaks of cellulose, hemicellulose, and lignin depending on the impregnation method and solution ratio. Thermogravimetric analysis and the limiting oxygen index indicated that the samples impregnated with lime solutions exhibited higher thermal stability than the unimpregnated wood. Both impregnation methods caused a decrease in water absorption and thickness swelling of the sample groups. Using a scanning electron microscope, the effect of the impregnation process on the structure of the wood was examined. In terms of surface properties, it was determined that the surface roughness value increased. On the contrary, it was observed that the contact angle value also increased. A significant difference emerged between the applied methods. In conclusion, the applied lime minerals are suitable substances to increase the flame resistance and thermal stability of black poplar wood.

In this work, we prepared heat-treated aramid pulp/silica aerogel composites (AP/aerogels) and investigated in detail the feasibility of improving thermal stability and thermal insulation via tailored heat treatment. The microstructure and FTIR spectra reveal that AP/aerogels are formed by a physical combination of the silica aerogel matrix and aramid pulps. When the heat treatment temperature increases, the density slightly decreases and then increases to the maximum due to the significant volume shrinkage. The pyrolysis of aramid pulp and the collapse of silica skeletons occur during heat treatment; nevertheless, the typical structures of AP/aerogels do not change significantly. It is also found that both the hydrophobicity and the thermal insulation decrease with the increasing heat treatment temperature. We note that when the heat treatment is at 600 °C, the AP/aerogel still maintains a low density of 0.19 g/cm3 and a contact angle of 138.5°. The thermal conductivity is as low as 26.11 mW/m/K, measured using the transient hot wire method. Furthermore, the heat-treated AP/aerogels can avoid heat shock and possible thermal hazards during practical thermal insulation applications. The onset temperatures of the thermal decomposition of AP/aerogels increase from 298.8 °C for an untreated one to 414.7 °C for one treated at 600 °C, indicating that the thermal stability of AP/aerogels is improved significantly. This work provides a practical engineering approach to expand the thermal insulation applications of silica aerogel composites.

Soft magnetic metallic absorbents suffer from severe oxidation, reduction in permeability and deterioration in microwave absorption when exposed to high temperatures. In this study, we prepared flaky 304 stainless-steel powders as new microwave absorbents via deformation-induced ferromagnetism. The 304 stainless-steel powders showed significant increases in saturation magnetization (Ms) from 1.03 to 82.46 emu/g when their shape was changed from spheroids to flakes; the Ms further increased to 92.29 emu/g after heat treatment at 500 °C in air. The permeability of 304 alloy powders also showed an obvious increase after ball milling and remained roughly stable after heat treatment at 500 °C in air. Moreover, the permittivity exhibited a sharp decrease after heat treatment, enabling the improvement of impedance matching and microwave absorption. After heat treatment at 500 °C in air for 100 h, the simulated reflection loss of 304 stainless-steel powders with wax still showed attractive levels, giving a minimum value of −22 dB and remaining below −6 dB over 8.5–16.5 GHz at a thickness of 2 mm. Our work can help to include paramagnetic alloy systems as new microwave absorbents for working in harsh environments.

Bio-based foams are growing and promising materials to replace petroleum-based foams because of their beneficial qualities including their affordability, outstanding fire resistance, high thermal insulation performance, eco-friendliness and the bio-sourced origin of the feedstock components. This study produced rigid bio-based foams using chemicals derived from plants, primarily from furfuryl alcohol and polyol derived from lignin. Lignin-based polyol and furfuryl alcohol were used to produce furan-lignin foams, which are free of formaldehyde and ozone damaging substances. Seven different furan-lignin foams were produced by substituting the toxic formaldehyde with a more eco-friendly glyoxal as a hardener while using diethyl ether and bentonite as blowing agent and filler respectively. Effects of these reagents on the quality of foams produced were assessed by varying their contents in the formulations. The properties of the produced bio-based foams such as compressive resistance, water absorption capacity, density and moisture content were evaluated. Further product characterizations: elemental composition, thermo-gravimetric analysis, Fourier transforms infrared spectroscopy and Scanning electron microscopy were carried out on the foams. The reaction leading to foam production was spontaneous at room temperature with an acid catalyst. Results showed that the concentrations of the blowing agent, hardener and filler, all had effects on the quality of the bio-based foams produced. Scanning electron microscopy results showed that the foams possessed closed cell morphologies, a rigid foam characteristic for good thermal and acoustic performance but modest water absorption, with cell widths of 10–200 μm, having high densities and strong compressive strengths as inherent characteristics. The results of the characterization indicated that the foams may be used as a thermal barrier or a support in construction and packaging applications because they had strong thermal stability, high compressive strengths, and a modest capacity to absorb water.

PVA-alginate hydrogel is a promising material for use in biomedical applications due to its desirable characteristics: biocompatible, durable, non-toxic, and low cost. However, the low gel strength of this composite limits its use in biomedical applications. This study aims to develop enhanced mechanical and thermal properties of poly(vinyl alcohol) PVA-alginate composite yarn by adding nanocellulose isolated from the sustainable oil palm empty fruit bunches (OPEFBs). The PVA-alginate composite yarns reinforced with nanocellulose were prepared with various nanocellulose contents (1 wt.%, 2 wt.%, and 5 wt.%). The composite's tensile strength exhibited an increasing trend with the addition of nanocellulose, while the elongation at break showed the opposite trend. Moreover, it was demonstrated that the composite's thermal degradation shifts to higher temperatures with the addition of nanocellulose. The observed activation energies for the thermal degradation calculated using the Coats-Redfern method exhibited a significant increment for the composites reinforced with nanocellulose. These results show that the addition of nanocellulose into the PVA-alginate matrix enhances the chemical and thermal properties of the resulting hydrogel. All these improvements have resulted from more abundant and robust hydrogen bonds generated by the nanocellulose presence.

Nanoscale FeS and FeS2 mixed phases were synthesized by one-pot decomposition of (N-anil-N-piperldtc)Fe1 as FeS#1), (N-piperldtc)Fe2 as FeS#2) and (N-anildtc)Fe3 as FeS#3) complexes as precursors, with the help of tri-n-octylphosphine oxide (TOPO) coordinating solvent. Their morphology, stability, size, optical and structural characteristics were observed using various material characterization instruments. In comparison to the FeS#2 nano-flower shape, FeS#1 and FeS#3 have a uniform nano-rod shape. A one-step decomposition pattern was obtained from the thermal gravimetric analysis (TGA) results with 3% final mass residual. The high-resolution transmission electron microscopy (HRTEM) image reveals an aggregation and size diameter of around 14.47–30.25 nm for the three samples. The optical response between 3.8 and 4.2 eV from the three samples shows that they are inconsiderable materials for solar cells application. The diffraction peaks for the three samples matched well with the FeS/FeS2. These nanoscale materials can be used in a variety of applications, including lithium-ion batteries, biosensors, hydrogen evolution, and multifunctional nanocomposite materials.

1%Pd/CeO2-SnO2 catalysts with varying Ce/Sn ratio were synthesized by counter-precipitation followed by calcination in a wide temperature range. The catalysts with Ce/Sn

Abstract Solar cells featuring polythiophenes as donors are one of the optoelectronic devices that hold notable promises for commercial application, profiting from the lowest synthetic complexity and excellent scalability. However, the complex phase behaviors of polythiophenes and their blends put constraints on modulating electrical performance and thus realizing stable performance under thermal stress. In this contribution, we present a multi‐technique approach that combines calorimetry, scattering, spectroscopy, and microscopy to thoroughly probe the thermodynamic mixing, thermal properties of materials, the evolution of nanoscale domain structure, and device performance of poly(3‐hexylthiophene) (P3HT) with a range of nonfullerene acceptors (NFAs) such as ITIC, IDTBR, and ZY‐4Cl. Accordingly, two blending guidelines are established for matching these popular NFAs with P3HT to enable highly efficient and thermally stable cells. First, blend systems with weak vitrification and hypo‐miscibility are excellent candidates for efficient solar cells. Furthermore, high thermal stability can be achieved by selecting NFAs with diffusion‐limited crystallization. The P3HT:ZY‐4Cl blend was found to endow the best performance of over 10% efficiency and an exceptionally high T80 lifetime of >6000 h under continuous thermal annealing, which are among the highest values for P3HT‐based solar cells. This realization of high thermal stability and efficiency demonstrates the remarkable potentials of simple polythiophene :nonfullerene pairs in electronic applications.

The effect of ultrasound treatment (300 W; 0, 5, 10, 15, 20 and 25 min) on the extractability of acid soluble collagen from yellowfin tuna skin and its structural, physicochemical and functional properties were investigated. Ultrasound treatments significantly increased collagen extraction yield from the tuna skin up to 2.7 times, compared to the conventional extraction with acetic acid. The level of proline, hydroxyproline and thermal stability of collagens increased by applying ultrasound while their native triple-stranded helical structure was well-preserved, as revealed by X-ray diffraction and FTIR spectroscopy. However, ultrasound treatment reduced the particle size of the collagens which increased their pH and salt induced solubility. The water holding capacity and the emulsifying properties of ultrasound treated collagens were also higher than those produced with the conventional method. Altogether, the results suggested that ultrasonication can be a promising assistant technology for improving native collagen extraction efficiency from tuna skin and its functionality but its duration should be carefully optimized.

Since their discovery in 2004, carbon dots (CDs), with particle sizes < 10 nm, have found use in various applications, mainly based on the material’s fluorescent properties. However, other potential uses of CDs remain relatively unexplored when compared to other carbon-based nanomaterials. In particular, the use of CDs as catalysts and as supports for use in catalytic reactions, is still in its infancy. Many studies have indicated the advantages of using CDs in catalysis, but there are difficulties associated with their stability, separation, and aggregation due to their small size. This small size does however allow for studying the interaction of small catalyst particles with small dimensional supports, including the inverse support interaction. However, recent studies have indicated that CDs are not stable under high temperature conditions (especially >250 °C; with and without a catalyst) suggesting that the CDs may agglomerate and transform under some reaction conditions. The agglomeration of the metal in a CD/metal catalyst, especially because of the CDs agglomeration and transformation at high temperature, is not always considered in studies using CDs as catalysts, as post-reaction analysis of a catalyst is not always undertaken. Further, it appears that under modest thermal reaction conditions, CDs can react with some metal ions to change their morphology, a reaction that relates to the metal reducibility. This review has thus been undertaken to indicate the advantages, as well as the limitations, of using CDs in catalytic studies. The various techniques that have been used to evaluate these issues is given, and some examples from the literature that highlight the use of CDs in catalysis are described.

Silica aerogels and their derivatives have outstanding thermal properties with exceptional values in the thermal insulation industry. However, their brittle nature restricts their large-scale commercialization. Thus, enhancing their mechanical strength without affecting their thermal insulating properties is essential. Therefore, for the first time, highly thermally stable poly(acrylamide-co-acrylic acid) partial sodium salt is used as a reinforcing polymer to synthesize hybrid P(AAm-CO-AAc)-silica aerogels via epoxy ring-opening polymerization in the present study. Functional groups in P(AAm-CO-AAc) partial sodium salts, such as CONH2 and COOH, acted as nucleophiles for the epoxy ring-opening reaction with (3-glycidyloxypropyl)trimethoxysilane, which resulted in a seven-fold enhancement in mechanical strength compared to that of pristine silica aerogel while maintaining thermal conductivity at less than 30.6 mW/mK and porosity of more than 93.68%. Moreover, the hybrid P(AAm-CO-AAc)-silica aerogel demonstrated improved thermal stability up to 343 °C, owing to the synergetic effect between the P(AAm-CO-AAc) and the silica aerogel, corresponding to the thermal stability and strong covalent bonding among them. These excellent results illustrate that this new synthetic approach for producing hybrid P(AAm-CO-AAc)-silica aerogels is useful for enhancing the mechanical strength of pristine silica aerogel without impairing its thermal insulating property and shows potential as an industrial heat insulation material.

Nanometric multilayers composed of immiscible Ag and Ni metals were investigated by means of molecular dynamics simulations. The semi-coherent interface between Ag and Ni was examined at low temperatures by analyzing in-plane strain and defect formation. The relaxation of the interface under annealing conditions was also considered. With increasing temperature, a greater number of atomic planes participated in the interface, resulting in enhanced mobility of Ag and Ni atoms, as well as partial dissolution of Ni within the amorphous Ag. To mimic polycrystalline layers with staggered grains, a system with a triple junction between a silver single layer and two grains of nickel was examined. At high temperatures (900 K and 1000 K), the study demonstrated grain boundary grooving. The respective roles of Ni and Ag mobilities in the first steps of grooving dynamics were established. At 1100 K, a temperature close but still below the melting point of Ag, the Ag layer underwent a transition to an amorphous/premelt state, with Ni grains rearranging themselves in contact with the amorphous layer.