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In order to improve the comprehensive performance of thermosetting phthalonitrile resin (PN) composites, a novel molten hybrid (Nd2O3@DM35) was successfully prepared by loading Neodymium Oxide (Nd2O3) on the surface of low melt‐point molten oxide (DM35). In thermal gravimetric analysis, the addition of 30 wt% Nd2O3@DM35 postponed the temperature of 5% mass loss (T5%) of PN hybrid (PN‐NdD30) from 485 to 521°C. A series of thermal aging experiments were designed to prove the thermal stability of modified PN. The surface morphology of PN‐NdD30 was mostly maintained after thermal aging. Compared with pure PN, the flexural strength (FS) and interlaminar shear strength (ILSS) of PN‐NdD30 composites at room temperature increased by 31.4% and 32.8%, respectively. After aging at 400°C for 20 min, the FS and ILSS retention rates of PN‐NdD30 composites were 78.4% and 91.5%, respectively. In this work, the introduction of novel hybrid improved the thermal stability of PN composites, while enhancing their mechanical properties at different temperatures. Based on all the results, the heat resistance and mechanical mechanism of PN‐NdD30 composites were carefully analyzed. Highlights: A molten hybrid was prepared by Nd2O3 and low melt‐point molten oxide.The novel hybrid can form a continuous protective layer at high temperatures.In the aging test, the mass loss of PN‐NdD30 was significantly reduced.Mechanical properties of PN composites at different temperatures were improved.A novel molten concept was introduced in the heat resistance modification of PN. [ABSTRACT FROM AUTHOR]

The present study investigated the use of expanded perlite (e‐perlite) as a sustainable and cost‐effective filler for EPDM (ethylene propylene diene monomer) rubber composites. Various amounts of e‐perlite were incorporated into EPDM to assess its impact on the composite properties, such as curing characteristics, physical and mechanical properties, crosslink density, thermal conductivity, thermal stability, surface roughness, and contact angle. The composite with 15 phr of e‐perlite exhibited approximately 20% higher crosslink density and a 12% increase in hardness, while slight decreases were observed in elongation at break and tensile strength. The FE‐SEM (field emission‐scanning electron microscopy), atomic force microscopy, and contact angle analysis have been performed to investigate the surface morphology and the hydrophobicity. The thermal properties of the composites were assessed through thermogravimetric analysis, thermal aging tests, and thermal conductivity measurements. The results showed that e‐perlite significantly improved the aging resistance and the thermal stability. The composites with 15 phr e‐perlite exhibited a 21% reduction in thermal conductivity and enhanced thermal isolation properties compared to the EPDM composite without e‐perlite. This work demonstrated the potential utilization of e‐perlite in EPDM as a green sustainable filler to enhance the thermal insulation and the stability properties of the composites, which may have practical applications in automotive, aerospace, construction, and electronic industries. Highlights: E‐perlite enhances the thermal insulation property of EPDM rubber composites.Higher e‐perlite content increases composite hardness and crosslink density.The thermal conductivity of EPDM is reduced by increasing e‐perlite content.EPDM/e‐perlite exhibits improved thermal stability and aging resistance.Potential uses in automotive, aerospace, construction, and defense industries. [ABSTRACT FROM AUTHOR]

Recent advances in luminescent materials highlight the significant impact of hydrogen isotope effects on improving optoelectronic properties. However, the research on the influence of the boron isotope effects on photophysical properties remains underdeveloped. This study focused on exploring the boron isotope effects in boron‐cluster‐based luminogens. In doing so, we designed and synthesized carborane‐based luminogens containing 98 % 10B and 95 % 11B, respectively, and observed distinct photophysical behaviors. Compared to the 10B‐enriched luminogens, the 11B‐enriched counterparts can significantly enhance luminescence efficiency, prolong emission lifetime, and reduce full‐width at half‐maximum. Additionally, increased thermal stability, redshifted B−H vibrations, and a fourfold enhanced electrochemiluminescence intensity have also been observed. On the other hand, the biological assessments of a 10B‐enriched luminogen reveals low cytotoxicity, high boron uptake, and excellent fluorescence imaging capability, indicating the potential application in boron neutron capture therapy (BNCT). This work presents the first comprehensive exploration on the boron isotope effects in boron clusters, and provides valuable insights into the rational design of organic luminogens for advanced optoelectronic and biomedical applications. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION Emulsions are thermally unstable systems. This research aimed to investigate the thermal stability of fish gelatin (FG) oil‐in‐water emulsions in the presence of poly‐γ‐glutamic acid (γ‐PGA) as an additive after heat treatment. The study assessed how γ‐PGA influences the thermal stability of FG emulsions over time, focusing on their properties, structure, and food application potential.The incorporation of γ‐PGA significantly enhanced the thermal stability of FG emulsions, preserving their morphology after heating. Emulsions containing 0.1% γ‐PGA showed no significant changes after 24 h at 90 °C, while emulsions without γ‐PGA experienced noticeable delamination. Rheological evaluations revealed that the energy storage modulus and loss modulus of FG–γ‐PGA emulsions remained consistently higher than those of FG emulsions, regardless of heating duration. Particle size analysis indicated minimal changes for FG–γ‐PGA emulsions (413 nm after 24 h) compared to a substantial increase for FG emulsions (1598 nm). After heating, FG–γ‐PGA emulsions demonstrated significantly higher emulsifying activity index (EAI) (74 m2 g−1 versus 22.7 m2 g−1) and emulsifying stability index (ESI) (97% versus 76%). Additionally, the texture properties of meat mince formulated with FG‐γ‐PGA emulsions were comparable to those containing fat, showcasing their potential as a fat replacement.The study concludes that γ‐PGA enhances the thermal stability of FG emulsions, maintaining their integrity and improving functional properties under heat treatment. These findings offer valuable insights for the formulation of thermally stable emulsions, presenting promising opportunities for innovative applications in the food industry. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

As the efficiency of single‐junction organic solar cells (OSCs) is about to break 20%, more research effort is needed to achieve long‐term device stability for commercialization. The complex active layer microstructure of bulk‐heterojunctions challenges the degradation mechanism study, especially for the morphological changes under thermal stress. In this work, this issue can be overcome by employing planar‐heterojunction (PHJ) OSCs with well‐defined bi‐layered structures, which enables effective control of the microstructure of polymer donor layers. The evolution of photovoltaic parameters of the PHJ OSCs under thermal stress is specifically revealed, which is strongly related to the inter diffusion of small molecular acceptors into the amorphous phases of the polymer donors. Increasing the crystallinity of polymer donors can effectively stabilize the donor/acceptor interfaces and the photovoltaic performances. The work puts forward effective strategies to improve the morphological stability of OSCs and alternative approaches for mechanistic studies on the thermal stability of OSCs. [ABSTRACT FROM AUTHOR]

The exploitation of borate‐based phosphors is garnered tremendous attention in wLEDs. Although previous research provided some insights into borates from the viewpoints of synthesis, structure, and defect evolutions, their photoluminescence (PL) with dopants is still insufficient for actual application, especially on aspects of efficiency/stability. Herein, to alleviate the above issues, a new type of lesser‐known high symmetry Ba3Y2B6O15 (BYB) codoped with Dy3+/Eu3+ phosphors are synthesized via multistep solid‐state reaction and possessed controllable PL based on nUV excitation, defect‐induced (self‐) PL, and energy transfer (ET) from Dy3+ to Eu3+. The origin of blue self‐PL is clarified based on oxygen‐related defects and optimized via adjusting synthetic atmosphere (air/Ar) and (co)doping dopants to control the defect content. Thanks to dense connectivity, and highly symmetric structure with perfectly ordered octahedral sites of Y3+ for accommodation of Dy/Eu and ET, “cool” white and red PL from Dy3+ and Eu3+, respectively, show high PL efficiency with narrow full width at half the maximum (fwhm). The phosphor also exhibits excellent thermal stability because of high bandgap and low electron‐phonon coupling. Finally, a high‐quality phosphor‐converted wLED (pc‐wLED) device is assembled via remote “capping” packaging by adopting the BYB: Dy/Eu and a 350 nm nUV LED chip. [ABSTRACT FROM AUTHOR]

Vitrimers are promising next‐generation materials, often exhibiting superior properties such as mechanical strength and solvent resistance compared to their thermoplastic counterparts, while still featuring recyclability due to their dynamic covalent crosslinks. The most common strategy to recycle vitrimers is via mechanical reprocessing at high temperatures, while others utilize chemical degradation to reobtain the constituent monomers. This work presents a new approach toward reprocessing by selectively breaking of the vitrimer's crosslinks, turning it back into a thermoplastic. This allows for reprocessing to be achieved in a more sustainable manner such as at lower temperatures and shorter times. After the desired shape has been obtained, facile re‐crosslinking turns the material into a vitrimer, with full restoration of thermal stability, mechanical properties, and gel fraction. To achieve this, a carbene C─H insertion strategy is utilized to introduce an imine‐based crosslinker into various thermoplastics and plastic mixtures to convert them into vitrimers. Properties typical of vitrimers such as a retained polymer network at high temperatures, and an Arrhenius‐type relationship between stress relaxation rate and temperature are observed, while its mechanical properties such as elongation at break and tensile toughness, particularly for plastic mixtures are significantly enhanced, first by crosslinking, then further enhanced up to 8 folds by the reversible crosslinking process. [ABSTRACT FROM AUTHOR]

At present, phosphor-in-glass is regarded as a superior encapsulation material substituting for organic materials to resolve the poor thermal stability of WLEDs. However, the serious erosion reaction between commercial red phosphor and the glass matrix restricts the development and application of red phosphor-in-glass. In this work, a novel Sr4Al14O25:Li+,Mn4+ (SAO) red phosphor-in-glass film (PiGF) with precursor glass xB2O3–(85 − x)Bi2O3–5Al2O3–10CaO was prepared using a low-temperature sintering technique. Crystallization was observed in the precursor glass with 40% and 45% B2O3 content at 570 °C for 30 min, with the crystalline phase mainly being Bi4B2O9. The glass transition temperature gradually increases from 420 to 496 °C with an increase in B2O3 content from 40 to 60%. The DSC simulation and experimental results show that the degree of erosion of SAO phosphors decreases with an increase in B2O3 content from 50 to 60% and with an increase in the co-sintering temperature from 570 to 590 °C, while the glass surface smoothness of the PiGFs decreases with increasing B2O3 content. 55% B2O3 and 570 °C are the optimal parameters. The PL and PLE of the PiGFs show that the luminous intensity increases and then decreases with increasing B2O3 content, with 55% B2O3 also being the optimal value. The PiGF shows a quantum efficiency of 46.62%, and the luminous intensity maintains 85.1% of its initial intensity at 348 K. [ABSTRACT FROM AUTHOR]

AbstractIn this article, n-eicosane@MUF phase change microcapsules were prepared by in-situ polymerization with n-eicosane as the core material and melamine urea-formaldehyde (MUF) resin as the shell material. The effects of pH values from 3.5 to 6.0 on the surface morphology, particle size distribution, latent heat of phase transformation, encapsulation degree, thermal stability, and permeability resistance of the microcapsules were investigated. The results showed that the surfaces of the microcapsules gradually became smooth with the increase of pH value, and their encapsulation degree and impermeability also increased roughly. When the pH = 5.5, the particle size of the microcapsule samples ranged from 1.5 to 9.7 μm, the melting enthalpy was 178.8 J/g, and the encapsulation degree was 86.6%, which had the best thermal stability and impermeability. However, when the pH = 6.0, the phenomenon of microcapsule shell rupture occurred and the above performance no longer occurred. [ABSTRACT FROM AUTHOR]

Given the highly temperature-sensitive nature of the polymorphic phase boundaries, attaining excellent piezoelectric coefficient with superior temperature stability in lead-free piezoceramics via direct compositional design remains a formidable challenge. We demonstrate the synergistic improvement of piezoelectric coefficient and thermal stability in lead-free piezoceramics via atomic-scale local ferroelectric structure design. Via modulation of the local Landau energy barrier at doping sites, we effectively mitigate fluctuations in piezoelectric d33. Our approach achieves an impressive d33 of ~430 pC/N with a minimal temperature fluctuation range (△d33 ~ 7%) across the room temperature to 100 °C in potassium sodium niobate ceramics. Further optimization through annealing extends this temperature up to 150 °C (△d33 ~ 8%) while maintaining a high d33 of ~380 pC/N, rivaling the performance of classic temperature stable lead zirconate titanate. This work establishes a framework for addressing the dilemma between high piezoelectric coefficient and inadequate temperature stability in lead-free piezoceramics. The authors reveal that the incorporation of doping elements with varying electronic structures and ionic radii alters the atomic-scale configuration, thereby affecting the local energy barrier associated with polarization rotation. [ABSTRACT FROM AUTHOR]

In this study, poly(butylene adipate‐co‐terephthalate) (PBAT) biocomposites were generated from spent coffee grounds (SCGs) or torrefied SCG (TSCGs) using a melt compounding process. TSCGs were obtained at torrefaction temperatures of 230, 245, 260, 275, or 290°C for a duration of 60 min. Torrefaction enhanced the hydrophobicity, grindability, and biomass stability of the resulting composites by eliminating hemicellulose. Various concentrations of SCGs (10 and 20 wt.%) and TSCGs (10, 20, and 30 wt.%) were compounded into PBAT. The thermal, mechanical, and degradation properties of PBAT biocomposites were investigated. As SCGs and TSCGs were introduced, the crystallization temperature drastically increased. Compared with PBAT biocomposites with SCGs, PBAT biocomposites with TSCGs exhibited higher thermal stability and hydrophobicity, and improved mechanical properties. Further, alkaline hydrolysis occurred at a faster rate for biocomposites with biofillers than for neat PBAT. Therefore, this study demonstrated the improved compatibility between SCGs and PBAT by torrefaction. [ABSTRACT FROM AUTHOR]

The effect of cyclization degree of nitrogen thermal pretreatment on the radial structure difference of polyacrylonitrile(PAN) oxide fibers is explored. In this paper, PAN fibers were isothermally heated in nitrogen at 170°C, 190°C and 210°C for 0, 10, 20, 30, 40, and 50 min, respectively, so as to obtain pre‐treated fibers with cyclization degrees of 0%, 19.96%, 35.18%, 38.92%, 42.80%, and 53.12%, respectively. The pre‐treated fibers were further stabilized in an oxygen atmosphere. The scanning results show that the radial structure difference of oxide fibers first decreases and then increases with cyclization degree increasing. Through FTIR, SEM and Raman characterization, it is found that this phenomenon is mainly related to the influence of nitrogen thermal pretreatment on oxygen diffusion. Therefore, to improve the thermal stability efficiency of PAN fibers by means of nitrogen thermal pre‐treatment, it is necessary to control the degree of cyclisation, and the appropriate degree of cyclisation in the present work is about 35%. [ABSTRACT FROM AUTHOR]

In order to study the availability of maltol-β-D-glucoside in cigarette flavoring, a comparative study was conducted on the stability, thermal pyrolytic behavior rate and fragrance application effect of maltol and maltol-β-D-glucoside. The results showed that the placement stability and thermal stability of maltol-β-D-glucoside were significantly higher than those of maltol. The main thermal cracking product of maltol-β-D-glucoside was maltol. Adding maltol-β-D-glycoside to cigarettes in different ways could achieve different flavoring effects. The thermal decomposition transfer rate of maltol-β-D-glucoside to mainstream smoke particulate matter was 1.46%, which was lower than the transfer rate of maltol (3.83%). However, cigarettes with added maltol-β-D-glucoside had better aroma release uniformity and stability than those with maltol. Therefore, maltol-β-D-glucoside was a precursor of flavors with good stability and aroma uniformity, which had certain advantages in the field of cigarette flavoring. [ABSTRACT FROM AUTHOR]

The wheat Angiotensin Converting Enzyme (ACE) inhibitory peptide was prepared by ultrasonic-assisted enzymatic hydrolysis method, and the inhibitory rate of ACE was the main index, and the degree of hydrolysis of gluten powder was the secondary index. The preparation process was optimized by single factor test and response surface method, and the stability of the inhibitory peptides was studied. The results showed that alkaline protease was suitable for enzymatic hydrolysis of gluten powder to produce wheat ACE inhibitory peptides. The optimal preparation conditions were ultrasonic time of 17 min, ultrasonic power of 300 W, enzymatic hydrolysis temperature of 60 °C, enzymatic hydrolysis time of 2.7 h, enzyme dosage of 3600 U/g, and gluten powder mass fraction of 5.1%. Under these conditions, the ACE inhibition rate of the prepared wheat ACE inhibitory peptides was 72.90%, and the hydrophobic amino acid content was 29.37 g/100 g. When the relative molecular weight of the inhibitory peptides was less than 3 kDa, it had good environmental stability and thermal stability, and also had good stability in a certain concentration of K+ and Mg2+, and could still maintain 79.26% of the original activity after simulated digestion in vitro. Therefore, ultrasound-assisted enzymatic hydrolysis method is an effective method to prepare wheat ACE inhibitory peptides. [ABSTRACT FROM AUTHOR]

In order to expand the application range of chickpea protein isolate (CPI) and improve the stability of low oil emulsion systems, this study used CPI as an emulsifier in oil-in-water (O/W) type CPI emulsions and investigated the effect of ultrasound treatment (20 kHz, 450 W) with different durations (0 min, 3 min, 6 min, 9 min, and 12 min) on the stability of CPI emulsions. The results showed that ultrasound treatment could significantly improve the stability of CPI emulsions compared with the untreated CPI emulsions. At 12 min of ultrasound treatment, the emulsification activity index (EAI) and emulsion stability index (ESI) were increased to (51.67±0.12) m²/g and (99.32±0.13) min, respectively. The average particle size became the smallest ((3.52±0.25) µm), resulting in finer and more uniform oil droplets. The absolute value of zeta-potential was the largest (52.57±1.31 mV), the Turbiscan stability index (TSI) was the lowest, and the storage, thermal and freeze-thaw stability of the CPI emulsions were all improved. As revealed by cold-field electron microscopy, CPI emulsions treated by ultrasound had a dense and regular internal structure, with smaller droplets and less spacing. In conclusion, a certain duration ultrasound treatment could improve the stability of CPI prepared emulsions, and the better effect was achieved at 12 min of ultrasound treatment. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) is a biodegradable polymer extensively used in packaging; however, its mechanical and barrier properties require enhancement for wider applications. Chitin-derived nanoflakes (CNFL), a two-dimensionally separated nanomaterial derived from α-chitin, possess high strength and toughness, making them ideal additives for improved PLA performance. This study investigated the effect of CNFL on the properties of PLA composite films. Incorporating CNFL significantly enhanced the mechanical properties of PLA, increasing its tensile strength and stiffness while preserving flexibility. This enhancement was attributed to the nucleating effect of CNFL, which increases crystallinity. Additionally, CNFL improved the thermal stability of the composite films by mitigating thermal deformation. Notably, the oxygen barrier properties of CNFL-filled PLA composites were also enhanced, demonstrating a significant reduction in oxygen permeability at optimal CNFL concentrations due to increased tortuosity of the oxygen diffusion path. Overall, CNFL-filled PLA composites exhibit great potential as renewable packaging materials, particularly for protecting sensitive products, such as food and pharmaceuticals, from oxidative degradation, thereby extending shelf life and maintaining quality. These findings suggest that CNFL-filled PLA composites are promising materials for advanced applications, offering a combination of enhanced mechanical performance, improved thermal stability, and superior oxygen barrier properties. [ABSTRACT FROM AUTHOR]

The thermal performance of natural-based composites remains a significant challenge in their industrial applications, especially in plat heat exchanger (PHE). This study aims to address this challenge by developing a bio-composite material using Green-epoxy biodegradable resin reinforced with banana fibre (Bn-GBC) and silicon carbide (SiC) as a filler, with the goal of improving its thermal conductivity and for fabrication PHE polymer biocomposite based. The study explores the effects of adding 2 mass% and 8 mass% SiC to the Bn-GBC, and an intumescent fire retardant (IFR) coating consisting of 29 mass% ammonium polyphosphate (APP) and 1 mass% boric acid was applied to the Bn-GBC/SiC samples. The manufacturing process involved the use of vacuum bag resin transfer moulding (VBRTM) technique. The study conducted Thermogravimetric analysis (TGA) tests under an O2 atmosphere, with processing parameters such as temperature and variation in heating rates set at 303–1173 K and 5, 10, and 15 °C min−1, respectively. The kinetic mechanism in the material was examined by calculating the kinetic parameters. The activation energy (Ea) was evaluated using model-free (the Friedman and KAS approaches) and fitting model of the Expanded Prout-Tompkins (Bna). In conclusion, all samples defined their kinetic parameter, the use of IFR reveals that increases Ea value by approximately 10–14%. TGA and cone calorimeter results indicated that the use of 8 mass% SiC improved the thermal stability of the composite compared to 2 mass% SiC. Moreover, from both thermal tests indicate that the application of a 16 mass% IFR (29Exolit/1BA) coating helped maintain the thermal stability and delay decomposition process. Thus, the PHE prototype was developed with 8 mass% SiC addition and without SiC addition. The Experimental and numerical heat assessment analysis was performed, it is proven that PHE/8SiC has a higher heat transfer compared to PHE/0SiC. [ABSTRACT FROM AUTHOR]

The development of lithium-ion batteries (LIBs) has progressed from liquid to gel and further to solid-state electrolytes. Various parameters, such as ion conductivity, viscosity, dielectric constant, and ion transfer number, are desirable regardless of the battery type. The ionic conductivity of the electrolyte should be above 10−3 S cm−1. Organic solvents combined with lithium salts form pathways for Li-ions transport during battery charging and discharging. Different structures, proportions, and forms of electrolytes become crucial under conditions conducive to Li-ions transport. The critical aspects of electrolytes during operation include their impact on capacity due to cycling efficiency, thermal stability, and the growth of lithium dendrites after multiple charge–discharge cycles. Research from the past to the present has primarily evolved around exploring these electrochemical parameters. Functional electrolytes address the drawbacks by incorporating different additives to mitigate issues arising from extreme environmental temperatures, lifespan, and thermal runaway of LIBs during operation. The concentration of additives used to improve cycle life typically does not exceed 5%. Apart from discussing general electrochemical properties, safety-related impacts, such as internal material effects from chemical reactions during charging and discharging, heat tolerance, and gas generation during thermal runaway, are primary focal points in this field. In addition, the review emphasizes recent advancements in quasi-solid and solid-state electrolytes that show promise for future applications due to their enhanced thermal stability and safety profiles. Furthermore, integrating deep eutectic solvents (DES) and ionic liquids (ILs) into electrolytes is explored for their potential to improve ionic conductivity and thermal stability, presenting a comprehensive overview of the evolving landscape in LIB electrolyte research. [ABSTRACT FROM AUTHOR]

In large scale manufacturing, polymeric materials for cable jackets are subjected to high temperature and shear, what can induce degradation processes. In result, changes in structure of polymer materials can occur what is critical for their applications. Permanent market pressure on increase of productivity and product reliability as well as rigorous administrative regulations in telecommunication industry are the driving forces for development and introduction of new advanced Flame Retardant Non-corrosive jacketing materials. Despite many studies, their behavior is still neither well characterized nor understood in large-scale production. The object of studies was characterization of a relationship between processing conditions and effects of degradation of FRNC cable materials. The main goal was to find the processing factors limiting the production speed. Materials taken into consideration were two commercially available thermoplastic FRNC compounds dedicated to fiber optic cables, based on linear low-density polyethylene/ethylene–vinyl acetate composites with high loading of aluminum trihydroxide and magnesium dihydroxide fillers. Thermal degradation of cable materials was studied with use of thermogravimetry and rheometry. The series of jacket samples under different processing conditions were produced. Material processing behavior was characterized, and tensile and heat aging performance of cable jacket were tested. The results showed that the primary limiting factors for line speed increase were the melt pressure and jacket tensile performance, but neither the shrinkage nor extruder motor load. The result and general approach to the FRNC investigation can be successfully used in cable industry or in other industries involving the extrusion of FRNC materials. [ABSTRACT FROM AUTHOR]

Non-isocyanate polyurethanes (NIPUs) are considered as a class of environmentally-safe polymers that show promising properties, such as chemical and mechanical resistance. An important feature that may limit some important applications is the thermal degradation behavior of NIPUs and their composites and hybrids. Hence, this article comprehensively reviews recent developments in these materials groups, focusing on the thermal stability and degradation routes. Influence of urethane linkage vicinity, molar mass and ratio of carbonate and amine components, and chemical structure on NIPU thermal degradation behavior was discussed. The onset temperature of degradation was found to be mainly influenced by urethane bonds concentration and crosslinking density of NIPU material. Chain length of amine component has also a significant impact on the thermal degradation profile. The incorporation of bio-sourced and nano-scaled additives (carbon- and silica-based nanoparticles) and their impact on thermal stability of NIPU matrix was analyzed, too, and future outlooks were given. [ABSTRACT FROM AUTHOR]

It is known that both the type and possibilities of application of cerium molybdates(VI) largely depend on the methods of their synthesis. Despite this, information on the type of molybdates(VI) formed as a result of a waste-free and environmentally friendly reaction occurring in the solid state between CeO2 and MoO3 in the air atmosphere, are divergent. The conducted research indicates that CeO2 and MoO3 react in air and in the temperature range of 500–650 °C to form two compounds, i.e. Ce5Mo8O32 and/or Ce2Mo4O15. Only the Ce5Mo8O32 compound, for the first time, was obtained as a pure phase. The synthesis of Ce5Mo8O32 takes place through an intermediate stage. In this stage, with the evolution of oxygen, the compound Ce2Mo4O15 is formed, which then reacts with excess CeO2 to Ce5Mo8O32. The obtained compound was characterized by XRD, DTA–TG, FTIR and UV–Vis/DRS methods. Ce5Mo8O32 has a green-olive colour and a density of 4.82 ± 0.05 g cm−3. It was found that this compound melts incongruently at the temperature of 960 ± 5 °C with the separation of solid CeO2. The value of the energy gap Eg ~ 2.59 eV allows the Ce5Mo8O32 compound to be classified as a semiconductor. The previously unknown properties of the compound with mixed cerium valence (Ce43+Ce4+Mo86+O32), characterized in this work, will constitute the basis for its application research. [ABSTRACT FROM AUTHOR]

Influence of titanium dioxide concentration on thermal properties of germanate-based glasses has been studied. Germanate glasses varying with TiO2 content were examined using DSC methods. The DSC curves exhibit two exothermic peaks, when GeO2 is substituted by TiO2. Based on DSC measurements, characteristic temperatures were determined. The studies demonstrate that glass transition temperature increases, whereas thermal stability parameters are reduced with increasing TiO2 concentration. The DSC curves were also acquired with different heating rates, and the Kissinger method was used to calculate the activation energy. X-ray diffraction analysis for germanate-based glass with TiO2 indicates that crystallization processes are more complex and several phases are formed during annealing. The absorption and emission spectra of glass samples doped with Er3+ ions were also examined before and after annealing process. [ABSTRACT FROM AUTHOR]

Natural fibre-based polymer composites have better improvements owing to their thermal and mechanical properties besides environmentally friendly quality. In the present work, biocomposite fabricated at kenaf fibres (KF) loading (30, 40, 50, and 60 mass%) with bio epoxy matrix by the hot compression moulding method, and their thermal and dynamic mechanical characterisation were investigated and examined. This study was conducted to investigate the thermal behaviour through thermogravimetric analysis (TGA) and the derivative of thermogravimetric analysis (DTG: the maximum thermal decomposition; Tmax), dynamic mechanical analysis (DMA) and thermomechanical analysis (TMA). The presented findings from TGA and DTG curves showed that the thermal stability improved with increasing the KF loadings, as evidenced by the higher residual mass % and the lower mass loss %. On the other hand, it was found that the biocomposite sample (50 mass% KF) exhibited higher thermal stability up to 558.82 °C. Furthermore, the DMA findings obtained exhibited the greatest value of the storage modulus (E') with the following order of KF bio composite (KF-50 > KF-60 > KF-40 > KF-30). On the other hand, the values of loss modulus (E'') were increased as follows KF-30 > KF-40 > KF-50 > KF-60. However, the results showed that 50 mass% of KF into epoxy biocomposites recorded higher loss modulus value (323.56 MPa) among all other bio composite samples, while the values of tan δ were increased as follows: KF-30 > KF-40 > KF-50 > KF-60. The results obtained for the TMA revealed a better coefficient of thermal expansion (CTE) for the sample (KF-50) compared to other samples. [ABSTRACT FROM AUTHOR]

Phase relations in the subsolidus area of the MgO–P2O5–Cr2O3 system were reinvestigated. The reactions were carried out by the method of multi-stage calcination of samples in the temperature range of 350–1150 °C. As a result of the conducted research, a new pyrophosphate with the formula Mg5Cr2 (P2O7)4 was discovered. This compound, crystallizing in the orthorhombic system, most likely exhibits the Fe52+Fe23+ (P2O7)4 structure. The infrared spectrum of the new pyrophosphate was presented. Mg5Cr2 (P2O7)4 melts incongruently at 1330 °C depositing Mg3Cr4 (PO4)6. The developed division of the MgO–P2O5–Cr2O3 system into subsidiary subsystems differs significantly from the one known from the literature. First of all, unlike in the literature, it takes into account the existence of the compound just discovered, as well as the other two phosphates, i.e. Mg3Cr4 (PO4)6 and Cr2P4O13. The melting points of mixtures of phases coexisting in the equilibrium state were estimated by the pyrometric method. All phosphates (V) with mixed cations, i.e. Mg5Cr2 (P2O7)4, Mg3Cr4 (PO4)6 and MgCr2 (P2O7)2, were tested for their use for colouring lead-free glaze fired once at 1050 °C. It turned out that the investigated phosphates act as dyes and ceramic layers of good quality and interesting colours were obtained. The optimal concentration of the applying phosphates was close to 3 mass%. [ABSTRACT FROM AUTHOR]

Vanadium-containing heteropoly compounds (HPCs), both in homogeneous and heterogeneous forms, represent a very promising class of materials with adjustable acid and oxidative properties. Herein, a catalytically active HPCs of H3+xPMo12–xVxO40 (x = 1–4) gross-composition were prepared by an environmentally friendly H2O2-affected approach and heterogenized in the form of insoluble salts with Cs+ counterion to obtain stable oxidation catalysts. Structural and textural characteristics of prepared compounds with Cs2.5+xH0.5PMo12–xVxO40 (x = 1–4) gross-composition were investigated by XRD, TGA, IR-ATR, ICP-AES, and N2 adsorption-desorption techniques, and their catalytic properties were tested in the oxidation of 5-hydroxymethylfurfural (5-HMF), a valuable biomass-derived platform chemical. The obtained materials were established to demonstrate retention of the initial Keggin structure during precipitation, low solubility in water, and high structural stability upon fourfold treatment with H2O for 3 h, as well as thermal stability up to 400°C. It was shown that a simple method of replacing H+ ions with large Cs+ cations allows a traditional homogeneous catalyst to function heterogeneously, which simplifies the process of its separation and recycling. The catalytic performance was shown to decrease gradually with reducing x value. The attained Cs5.5H0.5PMo9V3O40 and Cs6.5H0.5PMo8V4O40 solids revealed high activity in 5-HMF transformation to 2,5-diformylfuran with a yield of up to 93%, which opens up prospects for their application in various important fields of synthetic chemistry as heterogeneous oxidation catalysts. [ABSTRACT FROM AUTHOR]

The non-toxic and organic–inorganic double perovskite material (FA)2BiCuI6, has garnered significant curiosity as a double perovskites solar cell (DPSC) absorber layer owing to its exceptional optoelectronic characteristics, making it well-suited for photovoltaic (PV) applications. To assess the viability of (FA)2BiCuI6 as a prospective material for the solar cell absorption layer, the SCAPS-1D simulation tool is used to explore the optimal configuration of solar cell involving the different electron transport layer (ETL) and hole transport layer (HTL). ETLs such as PCBM, Ag2S, ZnO0.3S0.7, C60, Nb2O5, and ZnSe, along with HTLs like Mg-CuCrO2, CBTS, CFTS, GO, SWCNT, and CuI, are thoroughly considered for integration with the absorber layer. Each ETL is methodically examined in combination with each HTL to identify the optimal pairing with (FA)2BiCuI6. This analysis leads to the identification of a champion DPSC configuration, which is then further optimized to achieve higher efficiency. The champion device structured as FTO/Nb2O5/(FA)2BiCuI6/Mg-CuCrO2/Se demonstrates highest power conversion efficiency approximately 24.42%, open-circuit voltage = 1.077 V, short-circuit current density = 26.03 mA/cm2 and fill factor of 87.12% are observed after optimization of various solar cell parameters. This proposed configuration aims to optimize light absorption, charge carrier transport, and extraction efficiency to achieve high solar cell performance. This work proposes the most suitable DPSC configurations for PV applications, analysing on the basis of variables such as absorber layer thickness, shallow acceptor density, defect density, and interfacial defect density. Additionally, the investigation delves into the influence of series and shunt resistances on proposed DPSC structures. To gain deeper insights, the analysis incorporates JV curves and quantum efficiency plots for the proposed champion configuration. Device performance is stable with temperature at 300 K. [ABSTRACT FROM AUTHOR]

Water-based drilling fluids (WBDF) are often used over oil-based drilling fluids due to economic reasons and environmental regulations. Bentonite-free WBDF is preferred to aid in the reduction of formation damage. In many cases, this WBDF is formulated with xanthan gum. The performance of drilling operations is mainly affected by the drilling fluid formulation. The complex interactions among polymer concentration, thermal, and shear histories influence the rheological behavior of drilling fluids. The present study aims to analyze the effects of xanthan gum concentration on the rheological behavior of water-based drilling fluids. The experimental results performed in rotational rheometers revealed a relationship between concentration, yield stress, and thixotropic phenomena. The increase in xanthan gum concentration not only enhances the stability of the drilling fluid, allowing for more prolonged process interruptions without risking the fluid degradation but also improves the thermal stability of the sample. These findings show that the concentration of xanthan gum improves water-based drilling fluids' rheological and thermal stability. [ABSTRACT FROM AUTHOR]

Mayonnaise is an oil‐in‐water emulsion with 65–85% oil, and its physicochemical and sensory characteristics are greatly influenced by the type of oil used. The nutritional value and oxidation resistance of Pistacia atlantica oil (PAO) are very desirable due to the essential fatty acids (oleic and linoleic) and antioxidant compounds (phenolics and tocopherols). In this research, the physicochemical and sensory characteristics of mayonnaise sauce (MNS) with different levels of PAO (15% (MNS‐PAO15%), 30% (MNS‐PAO30%), and 100% (MNS‐PAO), as a substitute for soybean oil (SBO)) were compared with sauces containing SBO with antioxidants (MNS‐SBOA) or without antioxidants (MNS‐SBO) during storage for 30 days at 25°C. The results showed that MNS‐PAO and MNS‐SBO exhibited the lowest physical and thermal stability. The MNS‐PAO had the lowest values in peroxide (2.18 meq/kg oil) and thiobarbituric acid (0.21 mg MDA/kg oil) at the end of the storage period. Increasing the PAO level in the mayonnaise formula increased the b* value, but a decreasing trend of b* in these samples was observed during the storage period. The panelists gave the lowest sensory score to the MNS‐PAO sample, but they did not consider a significant difference between the samples containing SBO and the sample containing 15% PAO in terms of color, aroma, and overall acceptance. In general, mayonnaise containing 15% PAO was suggested as a desirable sauce in terms of emulsion and oxidation stability and sensory characteristics. [ABSTRACT FROM AUTHOR]

To enhance the applied value of transglutaminase (TGase), various methods have been employed to improve its catalytic properties. However, most modifications have targeted the N-terminus, while the role of the C-terminus in determining TGase properties has been overlooked. In this study, we focused on enhancing the thermal stability of Streptomyces hygroscopicus TGase by engineering its C-terminal region. Modeling revealed that the C-terminal loop interacts with the N-terminal loop through hydrogen bonds between Trp331 and N-terminal residues (Asp19, Ala20, Tyr21). Removing the last C-terminal residue (Ser322) had no significant effect on TGase stability, but deleting additional residues (Trp331, Gly330, Gln299) led to inactivation. Substituting Trp331 with Ala reduced TGase's half-life at 50 °C and specific activity by 50% and 70%, respectively, highlighting the importance of C-terminal interactions in TGase stability. We also attempted to fuse three self-assembling amphipathic peptides (SAPs) (EAK16, KL15, ELK16) and a C-terminal sequence (IGCIILT) from Sulfolobus tokodaii RNase HI to TGase. The fusion of IGCIILT increased TGase's half-life by 1.5-fold without affecting specific activity, while the three SAPs had little effect on stability. Structural analysis showed that the fusion of IGCIILT raised TGase's melting temperature by 5.2 °C and altered its tertiary structure. Our results indicate that the C-terminus is important for modulating TGase properties, and fusing "stabilization tags" like IGCIILT at the C-terminus is a promising strategy to enhance thermal stability. [ABSTRACT FROM AUTHOR]

A 220 GHz GaN‐based monolithic integrated frequency doubler with high continuous‐wave output power has been developed. The doubler achieves improved heat dissipation by establishing the terahertz (THz) monolithic integrated circuit topology with GaN Schottky barrier diodes integrated on a high thermal conductivity SiC substrate. It features six anodes to enhance the power‐handling capabilities. A refractory Schottky metal stack is adopted for better thermal stability. The doubler realizes satisfactory performance by introducing the suspended microstrip and an all‐in‐one output structure. For verification, a prototype of the proposed frequency doubler was fabricated and tested. Measured results show that the proposed doubler produces a continuous‐wave output power of 255 mW at 220 GHz with an efficiency of 14.6%, exhibiting excellent potential for powerful THz sources. [ABSTRACT FROM AUTHOR]

Nanocellulose is considered a promising and sustainable biomaterial, with excellent properties of biorenewability with improved mechanical properties. As a unique natural biopolymer, it has been applied to many different industries, where efficient and environmentally friendly productions are in demand. For the first time, ferns from the class Polypodiopsida were used for the isolation of cellulose fibers, which was performed using a chemo-mechanical method. As chemical treatment plays a crucial role in the isolation of nanocellulose, it affects the efficiency of the extraction process, as well as the properties of the resulting nanocellulose. Therefore, mechanical fibrillation was performed via grinding, while the chemical process consisted of three different treatments: alkali treatment, bleaching, and acid hydrolysis. In three different experiments, each treatment was separately prolonged to investigate the differing properties of isolated nanocellulose. Structural analysis and morphological analysis were investigated by SEM, EDS, FT-IR, and DLS. The thermal stability of cellulose fibers was investigated by TGA/DSC. The morphology of obtained nanocellulose was confirmed via SEM analysis for all samples, with particles ranging from 20 nm up to 600 nm, while the most consistent sizes were observed for NC3, ranging from 20 to 60 nm. FT-IR spectra showed prominent absorption peaks corresponding to cellulose, as well as the absence of absorption peaks, corresponding to lignin and hemicellulose. The EDS confirmed the elemental purity of nanocellulose, while TGA/DSC indicated higher thermal stability of nanocellulose, compared to untreated fern, which started to degrade earlier than nanocellulose. Such characteristics with unique properties make nanocellulose a versatile biomaterial for the industrial production of cellulosic materials. [ABSTRACT FROM AUTHOR]

'Rhythmite', Ca29(SiO4)8Cl26, an anthropogenic calcium chloride silicate from the Chelyabinsk coal basin (South Ural, Russia), was investigated using chemical microprobe analysis, in situ single-crystal X-ray diffraction analysis (27–727 °C), and Raman spectroscopy. 'Rhythmite' is orthorhombic, Pnma: a = 17.0749(6), b = 15.1029(5), c = 13.2907(4) Å, and V = 3427.42(18) Å3 (R1 = 0.045). The crystal structure of 'rhythmite' consists of a porous framework formed by Ca-O bonds and SiO4 tetrahedra with additional Ca2+ cations and Cl− anions in the structure interstices. The framework is built up from multinuclear [Ca15(SiO4)4]14+ fundamental building blocks (FBBs) cut from the crystal structure of α-Ca3SiO4Cl2 ('albovite'). The FBBs are linked by sharing common Ca atoms to form a network with an overall pcu topology. The empirical chemical formula was calculated as Ca29.02(Si7.89Al0.05P0.05)Ʃ7.99O32Cl26 (on the basis of Cl + O = 58). 'Rhythmite' is stable up to 627 °C and expands slightly anisotropically (αmax/αmin = 1.40) in the ab and bc planes and almost isotropically in the ac plane (α33/α11 = 1.02) with the following thermal expansion coefficients (×106 °C−1): α11 = 14.6(1), α22 = 20.5(4), α33 = 15.0(3), and αV = 50.1(6) (room temperature). During expansion, the silicate tetrahedra remain relatively rigid with average bond length changes of less than 0.5%. A structural complexity analysis indicates that 'rhythmite' is complex, with IG,total = 920.313 (bits/u.c.), which significantly exceeds the average value of structural complexity for silicates and is caused by the modular framework construction and the presence of a large number of independent positions in the crystal structure. [ABSTRACT FROM AUTHOR]

Background: A pelletizer paired with hot-melt extrusion technology (HME) was used to develop colon-targeted pellets for ketoprofen (KTP). Thermal stability and side effects in the upper gastrointestinal tract made ketoprofen more suitable for this work. Methods: The pellets were prepared using the enzyme-triggered polymer Pectin LM in the presence of HPMC HME 4M, followed by pH-dependent Eudragit® S 100 coating to accommodate the maximum drug release in the colon by minimizing drug release in the upper gastrointestinal tract (GIT). Box–Behnken Design (BBD) was used for response surface optimization of the proportion of different independent variables like Pectin LM (A), HPMC HME 4M (B), and Eudragit® S 100 (C) required to lower the early drug release in upper GIT and to extend the drug release in the colon. Results: Solid-state characterization studies revealed that ketoprofen was present in a solid solution state in the hot-melt extruded polymer matrix. The desired responses of the prepared optimized KTP pellets obtained by considering the designed space showed 1.20% drug release in 2 h, 3.73% in the first 5 h of the lag period with the help of Eudragit® S 100 coating, and 93.96% in extended release up to 24 h in the colonic region. Conclusions: Hence, developing Eudragit-coated hot-melt extruded pellets could be a significant method for achieving the colon-specific release of ketoprofen. [ABSTRACT FROM AUTHOR]

Biodiesel (methyl esters) has been produced using numerous catalysts to enhance its quality and related productivity. Generally, the raw materials for biodiesel production and its catalysts significantly impact the produced biodiesel's quality. In addition, the heterogeneous catalysts are promising as catalysts in the transesterification for biodiesel production and can be used continuously during this production. In particular, these catalysts are essential for green biodiesel production because of their high activity, thermal stability, and reusability. Hence, several homogeneous and heterogeneous (acidic and alkaline) catalysts for biodiesel production, particularly the naturally derived heterogeneous catalysts, are reviewed in this article. Further, the different heterogeneous catalysts for biodiesel production have been studied extensively as replacements for the respective homogeneous catalyst. Specifically, this replacement is aimed at the simultaneous esterification and transesterification of the nonedible and low-cost biomasses under moderate conditions producing biodiesel. Moreover, this study analyzes biodiesel's impact and long-term performance in various applications. Finally, it also reports the advancements in biodiesel production in terms of the catalysts used in it and its processes to aid further developments in biodiesel production. [ABSTRACT FROM AUTHOR]

A new "cardo" bisphenol viz., 1-(2-(1,1-bis(4-hydroxyphenyl)-3-oxoisoindolin-2-yl)ethyl)-3,4-dimethyl-1H-pyrrole-2,5-dione (PPH-MA) was synthesized in a two-step reaction sequence starting from phenolphthalein. PPH-MA was utilized as a step-growth monomer for the synthesis of a homo- and fourco-polycarbonates bearing pendant 2,3-dimethylmaleimido groups (PC-MAs) via solution polycondensation of PPH-MA or various mol % compositions of PPH-MA and bisphenol-A, respectively, with triphosgene.1H NMR spectroscopy confirmed the chemical structure and composition of PC-MAs. Inherent viscosity and number average molecular weight values of PC-MAs were in the range 0.45–0.64 dL g−1 and 18,300 − 36,200 g mol−1, respectively, indicating the formation of polymers of medium to reasonably high molecular weights. Tough, transparent and flexible films of PC-MAs could be cast from chloroform solution. X-ray diffraction studies indicated the amorphous nature of PC-MAs. The 10% weight loss temperature (T10) values of PC-MAs were in the range 373–443 °C indicating their good thermal stability. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries are widely used due to high specific energy, but the ethylene carbonate in the electrolyte reacts violently with the oxygen component produced by the nickel-rich cathode, leading to lithium precipitation. For this reason, we propose a new electrolyte with Fluorine ethylene carbonate as the main solvent, which replaces the reaction source. It is verified that the capacity retention rate of the FEC-based battery reaches 96% after 300 cycles. Besides, FEC-based batteries withstand severe nail penetration tests without thermal runaway. In a heating test, the thermal runaway trigger for the FEC-based battery was delayed by 54 s. This work provides ideas for the subsequent development of safe electrolytes. [ABSTRACT FROM AUTHOR]

The fuel cell carries the promise of being ecologically beneficial and being one of the renewable energy choices. Solid acids have super‐protonic behavior, allowing them to act as conductors. It can operate at high temperatures. Hydration, on the other hand, can be employed to increase the solid acid and performance. Furthermore, the size of the electrolyte membrane influences the conductivity, stability, and crystal structure of the fuel cell solid acid compounds. Very few studies have been conducted on solid acid fuel cells, which are still being researched in order to make them feasible as well as a trustworthy alternative to clean renewable energy. This review presents an outline of the variables or attributes and current challenges that influence the technical efficacy and performance of the unique super‐protonic conductors for solid acid fuel cells. [ABSTRACT FROM AUTHOR]

Vanadium‐based polyanionic materials are promising electrode materials for sodium‐ion batteries (SIBs) due to their outstanding advantages such as high voltage, acceptable specific capacity, excellent structural reversibility, good thermal stability, etc. Polyanionic compounds, moreover, can exhibit excellent multiplicity performance as well as good cycling stability after well‐designed carbon covering and bulk‐phase doping and thus have attracted the attention of multiple researchers in recent years. In this paper, after the modification of carbon capping and bulk‐phase nitrogen doping, compared to pristine Na3V2(PO4)3, the well optimized Na3V(PO3)3N/C possesses improved electromagnetic induction strength and structural stability, therefore exhibits exceptional cycling capability of 96.11% after 500 cycles at 2 C (1 C = 80 mA g−1) with an elevated voltage platform of 4 V (vs Na+/Na). Meanwhile, the designed Na3V(PO3)3N/C possesses an exceptionally low volume change of ≈0.12% during cycling, demonstrating its quasi‐zero strain property, ensuring an impressive capacity retention of 70.26% after 10,000 cycles at 2 C. This work provides a facial and cost‐effective synthesis method to obtain stable vanadium‐based phosphate materials and highlights the enhanced electrochemical properties through the strategy of carbon rapping and bulk‐phase nitrogen doping. [ABSTRACT FROM AUTHOR]

Metal organic framework (MOF) materials have attracted widespread attention due to their tunable structure, high porosity, and large specific surface area. MOF modified with functional groups were introduced into ionic polymers that could provide proton conduction, which could prepare proton exchange membranes with high proton conductivity. In this paper, UiO-66-NH2 were introduced into sulfonated polyphosphazene (SPFPP) to prepare composite proton exchange membranes, the thermal stability, swelling degree, water uptake, and proton conductivity were characterized. Composite membranes exhibits excellent thermal stability, the swelling degree of the composite membranes are lower than that of the pure SPFPP membrane. UiO-66-NH2 could improve the water retention capacity of composite membranes, resulting in higher water uptakes of composite membranes than pure SPFPP membranes. This higher water retention capacity could improve the proton conductivity of the membrane under high humidity conditions. The proton conductivity of composite membranes SP/UiO-66-NH2 -0. 6 reaches up to 0. 179 S/cm under 80 ℃, 100% RH, while the proton conductivity of pure SPFPP membranes is 0. 120 S/cm under the same conditions. [ABSTRACT FROM AUTHOR]

A series of La2 Mg4/3 Sb2/3 - x O6 ∶xMn4 + red phosphors were prepared via traditional high-temperature solid-reaction method, and their structure, morphology and spectral properties were investigated. The results show that La2 Mg4/3 Sb2/3 O6 belongs to the double-perovskite structure as La2 Mg4/3 Nb2/3 O6 does, and the incorporation of Mn4 + has no influence on the structure of the phosphors. La2 Mg4/3 Sb2/3 - x O6 ∶ xMn4 + phosphor exhibits two broad excitation bands at 360 and 510 nm, corresponding to the 4A2g→2T2g and 4A2g→4T2g transitions of Mn4 + respectively. Upon 360 nm excitation, La2Mg4/3Sb2/3 -x O6∶xMn4+ phosphor gives rise to a intense red emission band at 710 nm, which belongs to the 2 Eg→4 A2g transition of Mn4 +. The optimal concentration of Mn4+ in La2 Mg4/3 Sb2/3 O6 host was determined to be 0. 004, with quantum yield and color purity up to 89. 6% and 99%, respectively. A crystal field analysis for Mn4+ in the La2 Mg4/3 Sb2/3 O6 matrix was conducted based on the excitation and emission spectra, and the crystal field parameters Dq, B and C were calculated. The temperature quenching process of La2 Mg4/3 Sb2/3 - x O6 ∶xMn4 + phosphor was analyzed with the configurational coordinate diagram of Mn4 +, and the activation energy was calculated to be 0. 355 eV. Finally, a comparison between the emission spectra of La2Mg4/3Sb2/3 -x O6∶xMn4 + phosphor and the absorption spectra of phytochrome PR and PFR was provided, and the application prospect of La2 Mg4/3 Sb2/3 -x O6 ∶xMn4 + phosphor in LED plant illumination was preliminarily evaluated. [ABSTRACT FROM AUTHOR]

Levoglucosenone (LGO), a renewable compound obtained from cellulose biomass, has been utilized to prepare novel monomers bearing alkene functional groups. These monomer derivatives of LGO were subsequently cured via ultraviolet (UV)‐initiated radical thiol‐ene "click" chemistry with commercially available multifunctional thiols to obtain colourless, optically transparent cross‐linked thermosets. The monomers prepared in this work are unique due to utilising the internal double bond of the LGO ring during polymerization as part of the cross‐linked network. The thermal and mechanical properties along with the degradation of thermosets containing both ether and ester linkages within the LGO monomers were studied. These thermosets had tensile strengths of 1.3–3.3 MPa, glass transition temperatures between 23.2 and 27.2 °C, and good thermal stability of up to 300 °C. [ABSTRACT FROM AUTHOR]

In this study, the feasibility of using bamboo bark fibers as modifiers to enhance asphalt mortar performance was investigated. Bamboo bark fibers were modified with NaOH, KH570 silane coupling agent, and nano-SiO2, and their preparation methods were established. The modified fibers were assessed for their oil absorption, thermal stability, and hydrophobicity. The asphalt mortar was evaluated for three key indicators: rutting resistance, deformation resistance, and durability at high temperatures. The microscopic morphology and modification mechanisms of the fibers were also studied. The results showed that modification with NaOH increased fiber porosity and surface roughness, while KH570 and its hydrolysis products enabled nano-SiO2 grafting onto the fibers, improving their adsorption to asphalt. The NaOH-KH570-nano-SiO2 ternary-composite-modified bamboo bark fiber (NKSBF) demonstrated superior hydrophobicity, oil absorption, and thermal stability at the asphalt mixing temperature. Among the modified fibers, asphalt mortar containing 3% NKSBF showed the best performance based on three key indicators, increased the shear strength by 96.4% and the softening point by 7.1% compared to the base asphalt, and increased the ductility by 1% compared to lignin fiber asphalt mortar. The incorporation of 3% bamboo bark fibers improved the rutting resistance, deformation resistance, and durability of short-term-aged asphalt mortar, with NKSBF showing the most significant improvement. [ABSTRACT FROM AUTHOR]

Optically transparent polyimide (PI) films with good atomic oxygen (AO) resistance have been paid extensive attention as thermal controls, optical substrates for solar cells or other components for low Earth orbit (LEO) space applications. However, for common PI films, it is usually quite difficult to achieve both high optical transparency and AO resistance and maintain the intrinsic thermal stability of the PI films at the same time. In the current work, we aimed to achieve the target by using the copolymerization methodology using the fluorinated dianhydride 9,9-bis(trifluoromethyl)xanthene-2,3,6,7-tetracarboxylic dianhydride (6FCDA), the fluorinated diamine 2,2-bis [4-(4-aminophenoxy)phenyl]hexafluoropropane (BDAF) and the polyhedral oligomeric silsesquioxane (POSS)-containing diamine N-[(heptaisobutyl-POSS)propyl]-3,5-diaminobenzamide (DABA-POSS) as the starting materials. The fluoro-containing monomers were used to endow the PI films with good optical and thermal properties, while the silicon-containing monomer was used to improve the AO resistance of the afforded PI films. Thus, the 6FCDA-based PI copolymers, including 6FCPI-1, 6FCPI-2 and 6FCPI-3, were prepared using a two-step chemical imidization procedure, respectively. For comparison, the analogous PIs, including 6FPI-1, 6FPI-2 and 6FPI-3, were correspondingly developed according to the same procedure except that 6FCDA was replaced by 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA). Two referenced PI homopolymers were prepared from BDAF and 6FDA (PI-ref1) and 6FCDA (PI-ref2), respectively. The experimental results indicated that a good balance among thermal stability, optical transparency, and AO resistance was achieved by the 6FCDA-PI films. For example, the 6FCDA-PI films exhibited good thermal stability with glass transition temperatures (Tg) up to 297.3 °C, good optical transparency with an optical transmittance at a wavelength of 450 nm (T450) higher than 62% and good AO resistance with the erosion yield (Ey) as low as 1.7 × 10−25 cm3/atom at an AO irradiation fluence of 5.0 × 1020 atoms/cm2. The developed 6FCDA-PI films might find various applications in aerospace as solar sails, thermal control blankets, optical components and other functional materials. [ABSTRACT FROM AUTHOR]

The current research is devoted to the development and characterization of green antimicrobial polymer biocomposites for food packaging applications. The biocomposites were developed by melt compounding on the basis of two different succinate polymer matrices with varying chain stiffness—polybutylene succinate (PBS) or its copolymer with 20 mol.% of polybutylene adipate (PBSA). Fungi chitosan oligosaccharide (C98) and crustacean chitosan (C95) were used as antimicrobial additives. The rheological properties of the developed biocomposites were determined to clear out the most suitable temperature for melt processing. In addition, mechanical, thermal, barrier and antimicrobial properties of the developed biocomposites were determined. The results of the investigation revealed that PBSA composites with 7 wt% and 10 wt% of the C98 additive were more suitable for the development of green packaging films because of their higher ultimate elongation values, better damping properties as well as their superior anti-microbial behavior. However, due to the lower thermal stability of the C98 additive as well as PBSA, the melt processing temperatures of the composites desirably should not exceed 120 °C. Additionally, by considering decreased moisture vapor barrier properties, it is recommended to perform further modifications of the PBSA-C98 composites through an addition of a nanoclay additive due to its excellent barrier properties and thermal stability. [ABSTRACT FROM AUTHOR]

Thermoplastic polyimides (TPIs) are promising lightweight materials for replacing metal components in aerospace, rocketry, and automotive industries. Key TPI attributes include low density, thermal stability, mechanical strength, inherent flame retardancy, and intrinsic fluorescence under UV light. The application of advanced manufacturing techniques, especially 3D printing, could significantly broaden the use of TPIs; however, challenges in melt-processing this class of polymer represent a barrier. This study explored the processability, 3D-printing and hence mechanical, and fluorescence properties of TPI coupons, demonstrating their suitability for advanced 3D-printing applications. Moreover, the study successfully 3D-printed a functional impeller for an overhead stirrer, effectively replacing its metallic counterpart. Defects were shown to be readily detectable under UV light. A thorough analysis of TPI processing examining its rheological, morphological, and thermal properties is presented. Extruded TPI filaments were 3D-printed into test coupons with different infill geometries to examine the effect of tool path on mechanical performance. The fluorescence properties of the 3D-printed TPI coupons were evaluated to highlight their potential to produce intricately shaped thermally stable, fluorescence-based sensors. [ABSTRACT FROM AUTHOR]

This research study employs a comparative Multi-Criteria Decision-Making (MCDM) approach to select optimal thermoplastic materials for hybrid vehicle battery packs in the automotive industry, addressing the challenges posed by high-temperature environments. Through a detailed evaluation of materials based on criteria such as thermal stability, mechanical strength, chemical resistance, and environmental impact, the research identifies materials that enhance battery efficiency, longevity, and vehicle performance. Utilizing SWARA-ARAS, SWARA-EDAS, and SWARA-TOPSIS methods, the study systematically assesses and ranks various polymers, providing recommendations that prioritize safety, performance, and sustainability. The findings offer valuable insights for manufacturers in making informed material selection decisions, contributing to the advancement of sustainable automotive technologies. This research not only highlights the importance of material selection in the context of hybrid vehicle battery packs but also sets a foundation for future studies to explore emerging materials and decision-making frameworks, aiming to further enhance the efficiency and sustainability of hybrid vehicles. [ABSTRACT FROM AUTHOR]

A natural extract, i.e., urushiol, was employed to effectively cross-link and modify commercial wet-cured polyurethane acrylic resin. Comprehensive characterization of the paint film was performed using techniques such as FTIR, SEM, and TGA. The results indicated that the incorporation of urushiol significantly increased the cross-linking density of the resin, which in turn enhanced the film-forming properties, mechanical strength, and thermal stability of the paint film. Additionally, the study discovered that under isothermal conditions, the dynamic moduli (G′ and G″) of the paint film are related to the gel point frequency by a power law, aligning with the predictions of percolation theory. The application of the autocatalytic model has provided a novel approach to studying non-isothermal kinetic reactions, offering valuable insights for process optimization and further development of urushiol-based polyurethane. [ABSTRACT FROM AUTHOR]

The development of poly(lactic acid) (PLA) nanocomposites incorporating urchin-like WO3 particles through a cost-effective solution-casting method has led to significant enhancements in structural, thermal, optical, and rheological properties. The incorporation of these WO3 particles up to 7 wt% resulted in the formation of an irregular honeycomb-like morphology with broad pore sizes ranging from 14.1 to 24.7 µm, as confirmed by SEM and EDX analysis. The urchin-like WO3 particles acted as effective nucleating agents, increasing the crystallinity of PLA from 40% to 50% and achieving an impressive overall crystallinity rate of 97%. Differential scanning calorimetry (DSC) revealed an 11 K reduction in the crystalline phase transition temperature while maintaining stable melting (Tm) and glass transition (Tg) temperatures. Thermal analysis indicated a significant decrease in the onset of degradation and maximum thermal stability (Tmax), with a reduction of 21 K due to the incorporation of the WO3 particles. Optical measurements showed enhancement of UV-blocking properties from 9% to 55% with the WO3 particle loading. Rheological tests demonstrated substantial improvements in viscoelastic properties, including a remarkable 30-fold increase in storage modulus, suggesting enhanced gel formation. Although the nanocomposites showed minimal antibacterial activity against Escherichia coli and Staphylococcus aureus, they exhibited significant antifungal activity against Candida albicans. These results underscore the potential of the PLA/WO3 nanocomposites for advanced material applications, particularly where enhanced mechanical, thermal, optical, and antifungal performance is required. [ABSTRACT FROM AUTHOR]

Near‐infrared (NIR) phosphor‐converted light‐emitting diodes (pc‐LEDs) are considered as promising next‐generation light sources for optoelectronic and biomedical applications. Nevertheless, NIR phosphors with large bandwidths, long emission peaks, high external quantum efficiencies (EQEs) and valuable thermal stabilities are challenging to develop. Herein, this study reports a novel gallium germanate host, Ga3Al3Ge2O13 (GAGO), with a large bandgap and rigid host lattice for Cr3+ ion doping. The blue LED excitable GAGO:0.012Cr3+ phosphor can produce broadband NIR emission with a maximum intensity at 816 nm and a full‐width at half‐maximum (FWHM) of 187 nm. Notably, the phosphor also exhibits an excellent EQE of 35.8% and perfect thermal stability (I423 K/I298 K = 67.4%). Moreover, an attractive NIR afterglow duration of more than 24 h is achieved in the GAGO:0.004Cr3+ phosphor. The type and origin of the traps are discussed, and a possible long persistent luminescent (LPL) mechanism is proposed. Finally, an NIR pc‐LED based on a GAGO:0.012Cr3+ phosphor is fabricated. The results demonstrate that the obtained phosphors show great potential for use in night vision, nondestructive detection, bioimaging and information encryption. This study provides new insight into the development of broadband NIR luminescent materials with high efficiency, good thermal stability and extraordinary afterglow performance. [ABSTRACT FROM AUTHOR]

The increasing demand for white light‐emitting diode (WLED) has prompted the development of phosphors, in which Ce3+‐activated garnet has been representative and widely investigated. The optimization and improvement of performance have long been a focus in the phosphor area. However, the trade‐off of phosphor performance always exists and is difficult to satisfy simultaneously, thereby necessitating a better understanding of the design principles that tune spectra performance comprehensively. Herein, the defect‐induced spectral tuning mechanism in a Ce‐doped garnet solid‐solution phosphor Ca1.5‐xY1.5+xAl3.5+xSi1.5‐xO12:Ce3+ (CYAS:Ce3+) is promoted. The enhancement of luminescence intensity and thermal stability together with red‐shift of emission can be achieved by chemical unit co‐substitution of [Y3+‐Al3+] for [Ca2+‐Si4+], which originated from the increasing anti‐site vacancy. The related mechanism is fully elucidated by combining structural and spectral analysis with density functional theory (DFT) calculations. This study provides a subtle control for the performance‐tuning of phosphors, which can deepen the understanding of the design principle inside‐out and the subsequent development and exploration of novel optoelectronic functional materials. [ABSTRACT FROM AUTHOR]