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Eu2+‐doped phosphors have attracted the great attention of researchers in the past decade. However, Eu2+ dopant in inorganic hosts often suffers from the self‐oxidation effect, therefore causing the attenuated emission intensity and quantum efficiency. In this regard, developing Eu2+ doped phosphors with the prohibited self‐oxidation effect of Eu2+ and increased thermal stability is urgently required. Herein, an innovative cyan‐light emitting Li2CaSiO4:Eu2+/Eu3+, Lu3+ (LCSO) phosphor is designed. Both experimental results and theoretical calculations demonstrate that adding Lu3+ restricts the self‐oxidation of Eu2+ into Eu3+, thus improving the emission of Eu2+. Meanwhile, the Lu3+ introduction brings out excellent thermal stability. Finally, an efficient WLED with a color temperature (CCT) of 4573 K and a high color rendering index (Ra) of 84.2 is obtained using the as‐prepared phosphor due to the perfect compensation of the cyan light. As the introduction of Lu3+ improves the stability of Eu2+, a much greater difference in PL decay rate between Eu2+ and Eu3+ in LCSO is reached, thereby improving their sensitivity in temperature sensing. The strategy of Lu3+ introduction for prohibiting the self‐oxidation of Eu2+ for efficient and stable Eu2+ emission may stimulate some new ideas in designing high‐performance phosphors for more diverse applications. [ABSTRACT FROM AUTHOR]

Even though there have been significant advancements in the development of Cr3+‐activated near‐infrared (NIR) phosphors, the challenge still remains to develop highly efficient and thermally stable NIR phosphors. Here, the Ca4‐xZnxHfGe3O12:0.03Cr3+ solid solution phosphors with 834–806 nm NIR emission are constructed by substituting Zn2+ for Ca2+, thereby facilitating the formation of [ZnO6] luminescence site. The coexistence of [HfO6] and [Zn/CaO6] luminescence centers is confirmed through DFT calculation, time‐resolved photoluminescence (TRPL) spectroscopy, and low‐temperature‐photoluminescence (77 K) spectroscopy. The formation of [ZnO6] effectively resolves the issue of lattice mismatch between Cr3+ and Ca2+. Furthermore, the simultaneous enhancement of luminescence intensity and thermal stability is realized through a synergistic combination of lattice distortion and rigidity enhancement. By optimizing the substitution concentration of Cr3+, the internal quantum efficiency (IQE) of 92% and an external quantum efficiency (EQE) of 29% are finally achieved. Meanwhile, the thermal stability is also enhanced from 59%@400 K (x = 0) to 81%@400 K (x = 0.8). The developed NIR phosphor‐converted light‐emitting diodes (pc‐LEDs) exhibit promising prospects in the fields of security, biomedicine, non‐destructive testing and rapid identification. [ABSTRACT FROM AUTHOR]

The ever‐increasing demand for efficient and economic photonic materials has hastened the quest for robust, multifunctional phosphors. Herein, a dual‐mode luminescent SrLaLiTeO6:Er3+, Yb3+ double perovskite phosphor whose concentration‐dependent up and down‐conversion luminescence are investigated and underlying mechanisms are discussed. Temperature‐dependent up‐conversion luminescence of 2H11/2→4I15/2 transition exhibits negative thermal quenching, owing to the thermalization process from the 4S3/2 level. Temperature dependent Raman analysis confirms a decrease in the phonon lifetime from 0.43 to 0.28 ps indicating an increased number of phonon decay channels, which explains the rapid thermal quenching of up‐conversion emission at elevated temperatures. The diverse thermal quenching of the thermally coupled levels contributes to the exceptionally high relative sensitivity of 4.49 %K−1 at 140 K. A maximum sensitivity, Sr of 0.84 %K−1 (698 K) is obtained from the Raman‐PL intensity ratio (RPIR) of the ν1${\nu _1}$ band (719 cm−1) and the 986 nm emission band (4I11/2→4I15/2) of Er3+. Hence, by employing multi‐mode temperature sensing techniques a single phosphor can be used for optical thermometry for a broad temperature range from 90 to 698 K. In addition, the Near Infra‐Red (NIR)‐II emission of Er3+ corresponding to 4I13/2→4I15/2 transition shows excellent thermal stability, maintaining 72% of the room temperature intensity at 500 K. [ABSTRACT FROM AUTHOR]

New Nd3+-doped cadmium molybdato-tungstates with the chemical formula of Cd1−3x▯xNd2x(MoO4)1−3x(WO4)3x (where x = 0.0283, 0.0455, 0.0839, 0.1430, 0.1875, 0.2000, 0.2500, and ▯ denotes a vacant site in the crystal lattice) were successfully synthesized by the high-temperature solid state reaction method, using CdMoO4 and Nd2(WO4)3 as the initial reactants. The structure and change in their lattice parameters as a function of Nd3+ ion concentration were investigated by the XRD (X-ray diffraction) method. The surface morphology and grain size of the doped materials were characterized by SEM (scanning electron microscopy). Their thermal properties and initial reactants were analyzed by DTA-TG (differential thermal analysis coupled with thermogravimetry) techniques. The optical properties of the Nd3+-doped cadmium molybdato-tungstates, such as optical band gap, were determined by UV–vis–NIR (ultraviolet–visible–near infrared) spectroscopy. The EPR (electron paramagnetic resonance) technique provided information on the type of magnetic interactions between Nd3+ ions. [ABSTRACT FROM AUTHOR]

The ambient stability of copper oxide layers produced through thermal oxidation is a critical factor for their application in advanced photovoltaic devices. This study investigates the long-term stability of thermally grown sodium-doped copper oxides fabricated at 300 °C, 500 °C, and 700 °C. The structural, optical, and electronic properties of these oxide layers were examined after a 30-day period to understand how thermal oxidation temperature and sodium doping influence the durability and properties of copper oxide films. The results indicate that the stability of thermal copper oxide increases with oxidation temperature. The film produced at 700 °C maintained consistent optical properties, work function value, and structural integrity over time, demonstrating their robustness against environmental degradation. In contrast, the layers produced at lower temperatures (300 °C and 500 °C) showed more significant changes due to continued oxidation and adsorption from ambient. [ABSTRACT FROM AUTHOR]

Porous polymeric microspheres are among the most effective adsorbents. They can be synthesized from numerous monomers using different kinds of polymerization techniques with a broad selection of synthesis factors. The main goal of this study was to prepare copolymeric microspheres and establish the relationship between copolymerization parameters and the porosity and thermal stability of the newly synthesized materials. Porous microspheres were obtained via heterogenous radical copolymerization using 3-(trimethoxysilyl)propyl methacrylate (TMPSM) as functional monomers and trimethylolpropane trimethacrylate (TRIM) as the crosslinker. In the course of the copolymerization, toluene or chlorobenzene was used as the pore-forming diluent. Consequently, highly porous microspheres were produced. Their specific surface area was established by a nitrogen adsorption/desorption method and it was in the range of 382 m2/g to 457 m2/g for toluene and 357–500 m2/g in the case of chlorobenzene. The thermal degradation process was monitored by thermogravimetry and differential scanning calorimetry methods in inert and oxidative conditions. The copolymers were stable up to 269–283 °C in a helium atmosphere, whereas in synthetic air the range was 266–298 °C, as determined by the temperature of 5% mass loss. Thermal stability of the investigated copolymers increased along with an increasing TMPSM amount in the copolymerization mixture. In addition, the poly(TMSPM-co-TRIM) copolymers were effectively used as the stationary phase in GC analyses. [ABSTRACT FROM AUTHOR]

C14‐alkoxy/alkyl PBTTT‐OR‐R, a derivative of the prototype PBTTT polymer, is relevant for optoelectronic applications because it combines PBTTT‐like intercalation behavior with enhanced charge‐transfer absorption at longer wavelengths. Additionally, fundamental insights are achieved by comparing this alternating conjugated polymer in the presence and absence of homocoupling defects. While the homocoupling‐free oxidative variant, PBTTT‐OR‐R(O), as well as the Stille polymer with 19% homocoupling defects, PBTTT‐OR‐R(S), can both form co‐crystals when stoichiometrically mixed with PC61BM, the co‐crystal of the latter shows properties which are highly dependent on the thermal processing conditions because of the presence of these defects. The PBTTT‐OR‐R(S):PC61BM co‐crystal shows a low thermal stability and PC61BM can progressively be expelled upon heating. In cooling from the melt and depending on the cooling rate, mixtures of PBTTT‐OR‐R(S) and PC61BM show a competition between co‐crystallization (fast cooling) and separate crystallization (slow cooling). The PBTTT‐OR‐R(O):PC61BM co‐crystal is much more stable up to at least 260 °C and is not influenced by the applied cooling rate. These findings also translate to the device level. The performance of PBTTT‐OR‐R:PC61BM photodiodes is severely deteriorated after isothermal annealing in case of PBTTT‐OR‐R(S), whereas the thermally robust co‐crystals of PBTTT‐OR‐R(O) allow a more flexible design of optimized devices. [ABSTRACT FROM AUTHOR]

BACKGROUND: Algae oil has garnered widespread acclaim due as a result of its high purity of docosahexaenoic acid (DHA) and excellent safety profile. The present study aimed to develop stable nanoemulsions (NEs) systems containing DHA from algae oil through thermal sterilization by combining modified whey protein concentrate (WPC) with low methoxyl pectin (LMP), as well as to investigate the impact of LMP concentration on the thermal stability and the gastrointestinal delivery efficiency of DHA NEs. RESULTS: The addition of LMP enhanced the stability of the emulsion after sterilization, at the same time as improving the protective and sustained release effects of DHA in the gastrointestinal tract. Optimal effect was achieved at a LMP concentration of 1% (10 g kg−1 sample), the stability of the emulsion after centrifugation increased by 17.21 ± 5.65% compared to the group without LMP, and the loss of DHA after sterilization decreased by only 0.92 ± 0.09%. Furthermore, the addition of 1% LMP resulted in a substantial reduction in the release of fatty acids from the NEs after gastrointestinal digestion simulation, achieving the desired sustained‐release effect. However, excessive addition of 2% (20 g kg−1 sample) LMP negatively impacted all aspects of the NEs system, primarily because of the occurrence of depletion effects. CONCLUSION: The construction of the LMP/WPC‐NEs system is conducive to the protection of DHA in algae oil and its sustained‐release in the gastrointestinal tract. The results of the present study can provide reference guidance for the application of algae oil NEs in the food field. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Mullite–cordierite saggar materials commonly used in the industry are easily corroded by LiNixCoyMn1−x–yO2 (LNCM) materials during the synthesis of Li‐ion batteries. To extend their service life, the influence of varying the proportion of calcium hexaluminate (CA6) ranging from 0 to 12 wt% on the sintering behavior of the mullite–cordierite system was investigated. These samples were then tested to evaluate their physical characteristics, resistance to corrosion by LNCM materials, and thermal shock stability. The experimental results show that the open‐pore structure formed by the interstacking grains of CA6 effectively impedes further penetration of the corrosion phase. Moreover, the addition of CA6 resulted in the in situ formation of anorthite within the material, enhancing its sintering and bonding properties and significantly improving the material's corrosion resistance. Consequently, incorporating CA6 effectively enhances the saggar's thermal shock stability and corrosion resistance. [ABSTRACT FROM AUTHOR]

Polymerization of primary amine‐containing monomers is challenging because the amine inhibits polymerization catalyst activity. An alternative approach to access primary amine functionalized polymers is postpolymerization modification. To this end, the hydroaminoalkylation of vinyl‐terminated polyolefins with N‐(trimethylsilyl)benzylamine is used to prepare primary amine‐terminated polyolefins, with the free primary amine substituent being revealed upon hydrolytic work up. These materials are spectroscopically characterized, and an investigation of thermal properties by differential scanning calorimetry and thermogravimetric analysis is completed. These results show that the primary amine substituent increases the glass transition temperature and improves thermal stability. The reactive primary amine functionality is used in the photo‐oxidative dimerization of polyolefins to demonstrate how this elusive functionality can be applied in oligomer valorization. [ABSTRACT FROM AUTHOR]

Ion migration presents a formidable obstacle to the stability and performance of perovskite solar cells (PSCs), hindering their progress toward commercial feasibility. Herein, the degradation mechanism of PSCs caused by iodide ion migration, which leads to abnormal changes in photoluminescence transients at the buried interface of perovskite films, is investigated. In light of this problem, a novel strategy is proposed to mitigate ion migration by introducing poly(2‐vinylnaphthalene) into poly[bis(4‐phenyl)(2,4,6‐trimethylphenyl)amine] as the hole transport layer with improved ion‐blocking capability. Consequently, this layer effectively reduces defect concentration, suppresses ion migration, and modulates energy level alignment, leading to an impressive efficiency exceeding 23% for doctor‐bladed FAPbI3 PSCs. Moreover, the corresponding unencapsulated devices demonstrate remarkable durability, maintaining over 80% of their initial value after undergoing rigorous stress tests in accordance with the International Electrotechnical Commission 61215 standard for temperature, humidity, and illumination. These tests include 1000 h of thermal cycling and a long‐term operational test lasting 600 h under maximum power point tracking. [ABSTRACT FROM AUTHOR]

Semi‐interpenetrating polymer networks (semi‐IPNs), composed of two or more polymers, forming intertwined network‐architectures, represent a significant type of polymer combination in modern industry, especially in automotive and medical devices. Diverse synthesis techniques and plentiful raw materials highlight semi‐IPNs in providing facile modifications of properties to meet specific needs. An initiator‐free synthesis of semi‐interpenetrating polymer networks via Bergman cyclization (BC) is reported here, acting as a trigger to embed a second polymer via its reactive enediyne (EDY) moiety, then embedded into the first network. (Z)‐oct‐4‐ene‐2,6‐diyne‐1,8‐diol (diol‐EDY) is targeted as the precursor of the second polymer, swollen into the first polyurethane network (PU), followed by a radical polymerization induced by the radicals formed by the BC. The formation of the semi‐IPN is monitored via electron paramagnetic resonance (EPR) spectroscopy, infrared‐spectroscopy (FT‐IR), and thermal methods (DSC), proving the activation of the EDY‐moiety and its subsequent polymerization to form the second polymer. Stress−strain characterization and cyclic stress−strain investigations, together with TGA and DTG analysis, illustrate improved mechanical properties and thermal stability of the formed semi‐IPN compared to the initial PU‐network. The method presented here is a novel and broadly applicable approach to generate semi‐IPNs, triggered by the EDY‐activation via Bergman cyclization. [ABSTRACT FROM AUTHOR]

A family of ten amino‐containing bis(arylimino)acenaphthene‐nickel (II) bromide complexes varied in the electronic properties of para‐substituents (R = Me, iPr, tBu, OMe, Cl, F, NO2) as well as two amino‐free comparators (R = Me, Cl) are synthesized in good yield from their corresponding unsymmetrical N,N'‐ligands. All organic compounds are well characterized by different analysis techniques. On activation with Me2AlCl, all nickel complexes exhibit moderate to high activities with a maximum activity up to 14.19 × 106 g (PE) mol−1 (Ni) h−1 and deliver narrow dispersed polyethylene (PDI: 1.85–2.65) with adjustable molecular weight values (Mw: 5.27–18.49 × 105 g mol−1). The presence of remote fluoro‐ group and (4‐amino‐3,5‐dimethylphenyl)(phenyl)methyl group has their own unique influence on activity due to their different electronic and steric properties. Nevertheless, the latter with higher steric hindrance results in better thermal stability of the current catalytic system. Moreover, all polyethylene is highly branched and exhibits typical characteristics of thermoplastic elastomers, especially good mechanical properties (εb up to 1175%) and elastic recovery rate (up to 86%). [ABSTRACT FROM AUTHOR]

Brain‐inspired computing, reconfigurable optical metamaterials, photonic tensor cores, and many other advanced applications require next‐generation phase‐change materials (PCMs) with better energy efficiency and a wider thermal and spectral range for reliable operations. Germanium ditelluride (GeTe2), with higher thermal stability and a larger bandgap compared to current benchmark PCMs, appears promising for THz metasurfaces and the controlled crystallization of atomically thin 2D materials. Using high‐energy X‐Ray diffraction supported by first‐principles simulation, the atomic structure in semiconducting pulsed laser deposition films and metallic high‐temperature liquids is investigated. The results suggest that the structural and chemical metastability of GeTe2, leading to disproportionation into GeTe and Te, is related to high internal pressure during a semiconductor–metal transition, presumably occurring in the supercooled melt. Similar phenomena are expected for canonical GeS2 and GeSe2 under high temperatures and pressures. [ABSTRACT FROM AUTHOR]

Ge‐rich GeSbTe chalcogenide alloys have gained significant attention in the field of phase‐change materials due to their remarkable thermal stability and thus their suitability for integration in nonvolatile memories targeting embedded automotive applications. Herein, the effects of different encapsulating materials on the evolution and on the crystallization kinetic of N‐doped Ge‐rich GeSbTe films are focused on. These films are annealed with temperatures compatible with the back‐end‐of‐line of the complementary metal‐oxide‐semiconductor (CMOS) fabrication. First, it shows how the encapsulation layer thickness should be tuned in order to protect the layer from oxidation and at the same time to avoid delamination phenomena. TaN, C, TiN, SiC, and SiN used as encapsulating layers are compared. The segregation and crystallization of Ge‐rich GeSbTe alloys appear more homogeneous in the case of C, TiN, and SiC. On the contrary, the effects of an interfacial heterogeneous nucleation in the case of TaN and SiN are observed. It results in a different final morphology of the chalcogenide layer after annealing depending on the encapsulation, with different grain sizes and kinetic of phase separation. [ABSTRACT FROM AUTHOR]

The binuclear paddle‐wheel copper(II) complex tetrakis(μ‐3,4‐diethoxybenzoato‐κ2O:O′)bis[(ethanol‐κO)copper(II)], [Cu2(C11H13O4)4(C2H6O)2], has been synthesized and characterized. In each molecule, two CuII centres are bridged in a syn–syn fashion by four equatorial 3,4‐diethoxybenzoate ligands, the two axial positions being occupied by ethanol molecules. The thermal stability has been studied by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) techniques. The magnetic behaviour, studied by SQUID magnetometry, shows a CuII–CuII antiferromagnetic exchange interaction with 2J = −288 cm−1, a value that fits with a magnetic structure correlation established for compounds of this kind. [ABSTRACT FROM AUTHOR]

A new three‐dimensional (3D) coordination polymer, namely, poly[diaqua[μ5‐2,2′‐(1,3,5,7‐tetraoxo‐1,2,3,5,6,7‐hexahydropyrrolo[3,4‐f]isoindole‐2,6‐diyl)diacetato]barium(II)], [Ba(C14H6N2O8)(H2O)2]n, (I), has been synthesized by the microwave‐irradiated reaction of Ba(NO3)2 with N,N′‐bis(glycinyl)pyromellitic diimide {BGPD, namely, 2,2′‐(1,3,5,7‐tetraoxo‐1,2,3,5,6,7‐hexahydropyrrolo[3,4‐f]isoindole‐2,6‐diyl)diacetatic acid, H2L}. The title compound was structurally characterized by single‐crystal X‐ray diffraction analysis and powder X‐ray diffraction analysis, as well as IR spectroscopy. In the crystal structure of (I), the BaII ion is nine‐coordinated by six carboxylate O atoms from five symmetry‐related L2− dianions and one imide O atom, as well as two water O atoms. The coordination geometry of the central BaII ion can be described as a spherical capped square antiprism. One carboxylate group of the ligand serves as a μ3‐bridge linking the BaII cations into a one‐dimensional polynuclear secondary building unit (SBU). Another carboxylate group of the ligand acts as a μ2‐bridge connecting the 1D SBUs, thereby forming a two‐dimensional (2D) SBU. The resulting 2D SBUs are extended into a 3D framework via the pyromellitic diimide moiety of the ligand as a spacer. The 3D Ba framework can be simplified as a 5‐connected hexagonal boron nitride net (bnn) topology. The intermolecular interactions in the 3D framework were further investigated by Hirshfeld surface analysis and the results show that the prominent interactions are H...O (45.1%), Ba...O (11.1%) and C...H (11.1%), as well as H...H (11.1%) contacts. The thermal stability, photoluminescence properties and UV–Vis absorption spectra of (I) were also investigated. The coordination polymer exhibits a fluorescence emission with a quantum yield of 0.071 and high thermal stability. [ABSTRACT FROM AUTHOR]

Two new two‐dimensional (2D) coordination polymers (CPs), namely, poly[diaqua[μ4‐2,2′‐(1,3,5,7‐tetraoxo‐1,2,3,5,6,7‐hexahydropyrrolo[3,4‐f]isoindole‐2,6‐diyl)diacetato‐κ4O:O′:O′′:O′′′]cadmium(II)], [Cd(C14H6N2O8)(H2O)2]n (1), and poly[[tetraaqua[μ4‐2,2′‐(1,3,5,7‐tetraoxo‐1,2,3,5,6,7‐hexahydropyrrolo[3,4‐f]isoindole‐2,6‐diyl)diacetato‐κ4O:O′:O′′:O′′′][μ2‐2,2′‐(1,3,5,7‐tetraoxo‐1,2,3,5,6,7‐hexahydropyrrolo[3,4‐f]isoindole‐2,6‐diyl)diacetato‐κ2O:O′]dizinc(II)] dihydrate], {[Zn(C14H6N2O8(H2O)2]·H2O}n (2), have been synthesized by the microwave‐irradiated reaction of Cd(CH3COO)2·2H2O and Zn(CH3COO)2·2H2O, respectively, with N,N′‐bis(glycinyl)pyromellitic diimide {BGPD, namely, 2,2′‐(1,3,5,7‐tetraoxo‐1,2,3,5,6,7‐hexahydropyrrolo[3,4‐f]isoindole‐2,6‐diyl)diacetic acid, H2L}. In the crystal structure of 1, the CdII ion is six‐coordinated by four carboxylate O atoms from four symmetry‐related L2− dianions and two coordinated water molecules, furnishing an octahedral coordination geometry. The bridging L2− dianion links four symmetry‐related CdII cations into a 2D layer‐like structure with a 3,4‐connected bex topology. In the crystal structure of 2, the ZnII ion is five‐coordinated by three carboxylate O atoms from three different L2− dianions and two coordination water molecules, furnishing a trigonal bipyramidal coordination geometry. Two crystallographically independent ligands serve as μ4‐ and μ2‐bridges, respectively, to connect the ZnII ions, thereby forming a 2D layer with a 3,3‐connected hcb topology. Crystal structure analysis reveals the presence of n→π* interactions between two carbonyl groups of the pyromellitic diimide moieties in 1 and 2. CP 1 exhibits an enhanced fluorescence emission compared with free H2L. The framework of 2 decomposes from 720 K, indicating its high thermal stability. A comparative analysis of a series of structures based on the BGPD ligand indicates that the metal‐ion size has a great influence on the connection modes of the metal ions due to different steric effects, which, in turn, affects the structures of the SBUs (secondary building units) and frameworks. [ABSTRACT FROM AUTHOR]

The 0.29PSN-0.36PMN-0.35PT: x mol Nd2O3 (x = 0, 0.01, 0.015, 0.02, 0.025, and 0.03) piezoelectric ceramics are fabricated manufactured through the high-temperature sintering. Nd3+ doping significantly enhanced the piezoelectric and dielectric properties of PSN-PMN-PT, with the ceramic containing 0.025 mol Nd3+ exhibiting the optimal performance: d33 = 890 pC N−1, ɛr = 5735, d33* = 1094 pm V−1, Ec = 4.32 kV cm−1, Tm = 136 °C, and Pr = 4.32 µC cm−2. Phase structure analysis and Rayleigh analysis results show that the excellent dielectric and piezoelectric responses of the ceramic are mainly due to the synergistic effect of MPB and the significant improvement of nano-scale local structural heterogeneity. Moreover, the variation rate of d33 remained as low as 5% in the temperature range from room temperature to 120 °C. These comprehensive findings demonstrate that PSN-PMN-PT: 0.025 mol Nd2O3 ceramics excel in both their piezoelectric capabilities and thermal stability, thus rendering it an attractive material for high sensitivity sensor. [ABSTRACT FROM AUTHOR]

Because the commonly used phthalate plasticizers have adverse effects on the environment and health, there is a need to develop plasticizers with renewable material sources, non-toxic synthesis, and high plasticizing efficiency. In this study, an eco-friendly bio-based plasticizer, ALCE with excellent migration resistance was synthesized using linoleic acid (LA) and cinnamyl alcohol (CA) from biomass. The composition of ALCE was characterized and confirmed using FTIR and 1H NMR. The thermal stability, mechanical properties, and migration resistance of polyvinyl chloride (PVC) films plasticized with ALCE were compared to those plasticized with conventional plasticizers di(2-ethylhexyl) phthalate (DOP) and di(2-ethylhexyl) terephthalate (DOTP). The plasticizing mechanism of ALCE was elucidated through quantum chemical calculations. The initial decomposition temperature of ALCE-50 was found to be 43.66 °C higher than that of DOTP-50, making it more suitable for high-temperature applications. In tensile testing, PVC films containing 50 phr of ALCE exhibited an elongation at a break of 730.25%, demonstrating superior mechanical properties. Migration experiments also revealed that the migration quantities of ALCE were lower than those of DOP and DOTP. Overall, ALCE, as a plasticizer, enhances PVC's performance in various aspects and offers a new pathway for the development of eco-friendly plasticizers utilizing biomass resources. [ABSTRACT FROM AUTHOR]

Summary: This study investigated the impact of heating temperatures (70 °C to 90 °C for up to 14 h) on lycopene and β‐carotene degradation kinetics in gac aril paste. Carotenoids extracted via low‐volume hexane‐assisted ultrasonic extraction revealed a first‐order degradation pattern with high correlation coefficients (0.96–0.97). Lycopene degraded faster at 90 °C (k = 12.05 × 102 h−1) than at 70 °C (5.41 × 102 h−1), while β‐carotene displayed relatively slower degradation. Corresponding half‐life (t1/2) values for lycopene ranged from 5.75 to 12.81 h, while β‐carotene displayed values of 9.48–20.2 h. β‐carotene showed superior thermal stability compared to lycopene across all temperatures. Additionally, colour changes indicated decreased brightness with increasing temperature. The DPPH radical scavenging activity and FRAP values decreased during gac fruit heating. Overall, this study emphasises temperature‐induced declines in lycopene and β‐carotene levels in gac aril paste and offers insights into their degradation kinetics under thermal processing. [ABSTRACT FROM AUTHOR]

Modular synthesis can combine different functional modules to flexibly regulate comprehensive properties and study the diversity of compounds. This study established a modular bicyclic synthesis strategy of combining polynitro energetic module with iodine‐containing biocidal module. Compounds 1–6 with high iodine content (48.72–69.56 %) and high thermal stability (Td: 172–304 °C) were synthesized and exhaustively identified. By modular synthesis, the detonation properties and gas‐production of 3–6 improved greatly expanding their biocidal efficacy and maintained the iodine atomic utilization of iodine‐containing module. Notably, 4,5‐diiodo‐3,4',5'‐trinitro‐1,3'‐bipyrazole (5) and 3,5‐diiodo‐4,4',5'‐trinitro‐1,3'‐bipyrazole (6) exhibit high detonation velocities (D: 5903 m s−1, 5769 m s−1, respectively) and highest gas production of 212.85 L mol−1 and 217.66 L mol−1 after decomposition. This study diversifies polyiodio‐nitro compounds, and also inspire the implementation of similar synthesis strategies to provide family‐level synthetic solutions to energetic biocidal materials. [ABSTRACT FROM AUTHOR]

Organogels are polymer networks extended by a liquid organic phase, offering a wide range of properties due to the many combinations of polymer networks, solvents, and shapes achievable through 3D printing. However, current printing methods limit solvent choice and composition, which in turn limits organogels' properties, applications, and potential for innovation. As a solution, a method for solvent‐independent printing of 3D organogel structures is presented. In this method, the printing step is decoupled from the choice of solvent, allowing access to the full spectrum of solvent diversity, thereby significantly expanding the range of achievable properties in organogel structures. With no changes to the polymer network, the 3D geometry, or the printing methodology itself, the choice of solvent alone is shown to have an enormous impact on organogel properties. As demonstrated, it can modulate the thermo‐mechanical properties of the organogels, both shifting and extending their thermal stability range to span from ‐30 to over 100 °C. The choice of solvent can also transition the organogels from highly adhesive to extremely slippery. Finally, the method also improves the surface smoothness of prints. Such advances have potential applications in soft robotics, actuators, and sensors, and represent a versatile approach to expanding the functionality of 3D‐printed organogels. [ABSTRACT FROM AUTHOR]

The new microporous metal organic framework [La2(H2O)5(H2TPPE)]·3H2O (CAU‐54), is obtained in a hydrothermal reaction of the linker 1,1,2,2‐tetrakis(4′‐phosphonophenyl)ethylene (H8TPPE) and La3+ ions. The extensive characterization including temperature‐dependent crystal structures and spectroscopic properties allowed to understand the unique, multi‐responsive material properties. CAU‐54 exhibits rarely observed reversible photochromism as well as turn‐on photoluminescence by various external chemical or physical stimuli including change of pressure, solvent exchange, and temperature variation. These properties can be unequivocally assigned to the presence of tetraphenylethylene (TPE) moieties of the linker molecules within the MOF, i.e., the ordered spatial arrangement of the linker molecules, the presence of accessible pores as well as the coordination flexibility of the phosphonate groups and the rotational freedom of the linker. By temperature‐dependent steady‐state and time‐resolved luminescence studies, it is shown that this compound exhibits a) blue fluorescence that becomes effectively quenched at room temperature, b) green efficient luminescence with thermal stability up to 400 K, and c) red phosphorescence correlated to the observed photochromism. In addition, CAU‐54 shows unusual thermal expansion properties as shown by temperature‐dependent powder X‐ray diffraction measurements with identified transition points that correlate with the observed temperature‐dependent changes in the photoluminescence. [ABSTRACT FROM AUTHOR]

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

The need to increase thermal power stability and energy conservation have spurred the interest in various renewable energies. A diverse range of fabrication techniques and architectures have been developed to meet the global energy demand. Perovskite solar power technologies are the next emerging generation of photovoltaic thermal power systems for an enhanced and stable power supply. Thus, this project examines the thin radiation thermal stability of combined magneto-hybrid silicon oxide (SiO2) and aluminum oxide (Al2O3) nanoparticles in exothermic propylene glycol (C3H8O2)-Williamson fluid for perovskite thermal cells improvement. Without particles agglomeration, the fluid flow is influenced by lower wall velocity, Joule heating and Williamson shear stress in a bounded domain. An invariant coupled differential model is obtained through the similarity transformation of the governing model. The solutions to the invariant model is provided using semi-discretized finite difference method. The outcomes revealed that nanoparticles thermal propagation for perovskite power generation is strengthened with rising Brinkman number, radiation, and Frank-Kamenetskii terms. Also, criticality is raised at the unstable thermal region but damped at the stable thermal regime. [ABSTRACT FROM AUTHOR]

Zearalenone, a prominent mycotoxin produced by Fusarium spp., ubiquitously contaminates cereal grains and animal feedstuffs. The thermal stability of zearalenone creates serious obstacles for traditional removal methods, which may introduce new safety issues, or reducing nutritional quality. In contrast, biological technologies provide appealing benefits such as easy to apply and effective, with low toxicity byproducts. Thus, this review aims to describe the occurrence of zearalenone in cereals and cereal-based feedstuffs in the recent 5 years, outline the rules and regulations regarding zearalenone in the major countries, and discuss the recent developments of biological methods for controlling zearalenone in cereals and cereal-based feedstuffs. In addition, this article also reviews the application and the development trend of biological strategies for removal zearalenone in cereals and cereal-based feedstuffs. [ABSTRACT FROM AUTHOR]

A series of Ni-substituted LaCu1-xNixO3 (x = 0, 0.1, 0.3, 0.5 and 0.7) catalysts were prepared by a mechanochemical synthesis method and the prepared samples were used in catalytic combustion of methane. The catalytic results indicated that the partial substitution of Ni affected the catalytic performance and the increase in nickel content increased the catalytic activity and among the prepared catalysts the LaCu0.5Ni0.5O3 sample possessed the highest catalytic activity and thermal stability. The results showed that methane conversion reached from 7.8 to 73.8% at 500 °C with the substitution of Ni in the amount of x = 0.5. Also, the addition of Ni instead of Cu in the LaCu1-xNixO3 led to an increase in total pore volume and specific surface area and a decrease in average crystalline size. According to O2-TPD profiles of the LaCu1-xNixO3 catalysts, mobility of lattice oxygen (O2−) has a crucial role in determining the performance of these catalysts. The H2-TPR results indicated that the addition of Ni slightly improved the reducibility of catalysts. Furthermore, a decrease in calcination temperature of LaCu0.5Ni0.5O3 catalyst resulted in an increase in the catalytic activity due to the enhancement in the concentration of oxygen vacancy and specific surface area. Also, the results revealed that the increase in feed ratio (CH4/O2) leads to an increment in methane conversion. [ABSTRACT FROM AUTHOR]

In the present study, the effect of varying titanium dioxide (TiO2) nanoparticles on the dielectric, thermal, and corrosion characteristics of PI-based composites prepared by spark plasma sintering was investigated. The results obtained revealed that the TiO2 nanoparticles were uniformly dispersed within the PI matrix. Addition of TiO2 into the neat PI markedly reduced its dielectric constant and electrical conductivity by 72.7% and 82.3%, respectively, as well as enhancing its breakdown strength by 16.7% at 8 wt% TiO2 loading. The nanocomposites depict better thermal stability and heat-resistance index characteristics when compared to the PI. Additionally, the produced nanocomposites exhibit improved corrosion resistance than that of the neat PI. The remarkable improvement in the dielectric, thermal stability, and corrosion resistance of the nanocomposites is achieved by better dispersion of the TiO2 particles in the polymer matrix. The enhancement in properties suggests TiO2/PI-based nanocomposites potential for a variety of applications in electrical insulation, thermal management, and harsh environment. [ABSTRACT FROM AUTHOR]

A novel phenylethynyl-terminated siloxane-containing ortho -hydroxy polyimide (O-SPI) was synthesized and physically blended with thermoplastic polyimide (PI) to enhance both the thermal and mechanical properties of polyimide, addressing the growing demand for high-performance materials in harsh environments. The blend underwent conversion to semi -Interpenetrating Polymer Networks (semi -IPNs) and benzoxazole structures through thermal curing of reactive phenylethynyl groups and thermal rearrangement of ortho-hydroxy imide units. The trends in thermal and mechanical properties were investigated in relation to the chemical structures and varying mass fraction of O-SPI. The covalent incorporation of semi -IPNs and rigid benzoxazole structures restrict segmental motion while the backbone linkage confers the toughness of the blends. These synergistic effects insure the cured blends with high glass transition temperatures (472.51°C) and tensile strength (117.81 MPa) simultaneously, demonstrating their potential for applications in challenging conditions. [ABSTRACT FROM AUTHOR]

Poly(butylene succinate) (PBS) exhibits many advantages, such as renewability, biodegradability, and impressive thermal and mechanical properties, but is limited by the low melt viscosity and strength resulted from the linear structure. To address this, vitrimeric network was introduced to synthesize PBS vitrimers (PBSVs) based on dynamic imine bonds through melt polymerization of hydroxyl-terminated PBS with vanillin derived imine containing compound and hexamethylene diisocyanate using trimethylolpropane as a crosslinking monomer. PBSVs with different crosslinking degrees were synthesized through changing the content of the crosslinking monomer. The effect of crosslinking degree on the thermal, theological, mechanical properties, and stress relaxation behavior of the PBSVs was studied in detail. The results demonstrated that the melt viscosity, melt strength, and heat resistance were enhanced substantially without obvious depression in crystallizability, thermal stability, and mechanical properties through increasing crosslinking degree. In addition, the PBSVs exhibit thermal reprocessability with mechanical properties recovered by more than 90% even after processing for three times. Furthermore, PBSV with improved melt properties shows significantly improved foamability compared to commercial PBS. This research contributes to the advancement of polymer technology by successfully developing PBS vitrimers with improved properties, showcasing their potential applications in sustainable and biodegradable materials. [ABSTRACT FROM AUTHOR]

Nitrocellulose (NC) has been used since the late 1800ʹs in numerous energetic formulations; however, the effect of processing agents (solvents, etc.) on performance has not been thoroughly detailed. For illuminate applications, this is critical as spectral purity and dominant wavelength must meet specifications. In this effort, six processing agents (water, ethanol (EtOH), isopropyl alcohol (IPA), ethyl acetate (EtAc), acetone, and tetrahydrofuran (THF)) are evaluated and the effect they have on the NC fibers and subsequent performance is detailed. XRD and FTIR analysis indicates that the choice of processing agent directly affects the molecular integrity of the NC fibers due to the inhibition of NO2 bonds as well as freeing of hydrogen bonds between polymer chains during solubilization. Time-step FTIR analysis indicated that the weak nitrate ester bond (RCH2-ONO2) is targeted when processed in tetrahydrofuran, ethyl acetate, or acetone, and if heavy solvent interaction occurs, can lead to the autocatalytic decomposition of NC, when heat treated at 110°C. Spectral performance is detrimentally impacted as a result of such interactions. While all six processing agents for red-light illuminant formulations met the military requirements (i.e., spectral purity and wavelength), only ethanol and isopropyl alcohol processed formulations met the military required wavelength of 540 ± 20 nm for green-light illuminants. The IPA processed formulations exhibited the best results with spectral purity values of 69.0% and 94.8% for green and red-light illuminants, respectively. [ABSTRACT FROM AUTHOR]

The industrial world exposes living organisms to a variety of metal pollutants. Here we investigated whether such elements affect G-rich sequences susceptible to fold into G-quadruplex (GQ) structures. Thermal stability and conformation of these oligoncleotides was studied at various molar ratios of a variety of heavy metal salts using thermal FRET, transition-FRET (t-FRET) and circular dichroism. Metal ions affected the thermal stability of the GQs to different extents; some metals had no effect on T m while other metals caused small to moderate changes in T m at 1:1 or 1:10 molar ratio. While most of the metals had no major effect, Al3+, Cd2+, Pb2+, Hg2+ and Zn2+ altered the thermal stability and structural features of the GQs. Some metals such as Pb2+ and Hg2+ exhibit differential interactions with telomere, c-myc and c-kit GQs. Overall, toxic heavy metals affect G-quadruplex stability in a sequence and topology dependent manner. This study provides new insight into how heavy metal exposure may affect gene expression and cellular responses. • Heavy metal ions affect the thermal stability of the G-quadruplexes to different extents. • Al3+, Cd2+, Pb2+, Hg2+ and Zn2+ altered the thermal stability and structural features of the GQs. • Pb2+ and Hg2+ exhibit differential interactions with telomere, c-myc and c-kit G-quadruplexes. • Toxic heavy metals affect stability of G-quadruplexes in a sequence and topology dependent manner. • Heavy metal exposure may affect gene expression and cellular responses through direct DNA binding. [ABSTRACT FROM AUTHOR]

The role of phosphate-coordinating arginine residues in the thermal stability of uridine phosphorylase from Shewanella oneidensis MR-1 was investigated by mutation analysis. Uridine phosphorylase mutant genes were constructed by site-directed mutagenesis. The enzyme mutants were prepared and isolated, and their kinetic parameters were determined. It was shown that all these arginine residues play an important role both in the catalysis and thermal stability. The arginine residues 176 were demonstrated to form a kind of a phosphate pore in the hexameric structure of uridine phosphorylase, and they not only contribute to thermal stabilization of the enzyme but also have a regulatory function. The replacement of arginine 176 with an alanine residue resulted in a significant decrease in the kinetic stability of the enzyme but led to a twofold increase in its specific activity. [Display omitted] • Phosphate-binding arginines are essential for enzyme catalysis and thermal stability. • Mutations of active-site arginines to lysine lead to a decrease in enzyme activity. • Temperature optimum is lower for A rg28Lys and Arg46Lys mutants, higher for Arg89Lys. • Arginines 176 of three subunits of hexamer form an additional phosphate-binding site. • Arg176Ala mutant has lower thermal stability and affinity for phosphate. [ABSTRACT FROM AUTHOR]

Chitosanase plays a pivotal role in the production of chitooligosaccharide. Nevertheless, there is untapped potential for enhancing both its catalytic efficiency and thermostability, which could significantly bolster its therapeutic and biotechnological applications. In this study, two computer-aided protein design methods, namely Fireprot and PROSS, were utilized to pinpoint 6 single Bacillus subtilis chitosanase BsCsn46A mutants (S126A, D191A, K70A, L159I, K104P, and A129L) as well as 4 multiple mutants (K70A/S126A, K70A/S126A/K104P, K70A/S126A/L159I, and K70A/S126A/K104P/L159). The wild-type (WT) and all 10 BsCsn46A mutants displayed robust adaptability across a broad pH range, exhibiting peak activity within the pH spectrum of 5.5 to 9.5. The results demonstrated that, compared to the WT, 9 out of 10 mutants exhibited significantly heightened chitosanase activity, with the sole exception being the D191A mutant, which displayed activity levels nearly identical to the WT. Notably, the A129L displayed an impressive 20% increase in the enzyme activity at elevated temperatures, specifically in the range of 55–80°C. Assessing protein stability, results indicated that all samples maintained stability when incubated at 30°C for 1 h. However, when subjected to a higher temperature of 40°C for 1 h, only the A129L mutant retained stability, which persisted even after an extended incubation period of 3 h at 40°C. Furthermore, a thermal stability analysis revealed noteworthy differences between the WT and the mutants. The WT chitosanase activity diminished by 50% after brief 30-min incubation at 50°C, whereas the K70A/S126A, K70A/S126A/K104P, and A129L mutants maintained 50% of their activity for approximately 2 h under the same conditions. In summary, the study provides valuable insights into the thermostability and catalytic activity of chitosanase, highlighting promising candidates for industrial chitosanase applications. [ABSTRACT FROM AUTHOR]

Current research presents the nonlinear static/dynamic response of functionally graded (FG) porous nanotubes in the thermal pre- and post-buckling regimes. The case of temperature-dependent FG nanotubes with even distributed porosities subjected to uniform temperature rise is considered. The stability and vibration characteristics are analyzed for the uniformly heated nanotube surrounded by a nonlinear elastic foundation. The nonlinear equations of motion are derived using the Hamilton principle for the thermally pre/post-buckled nanotube in the framework of nonlocal strain gradient theory. The size-dependent governing equations are established based on the uncoupled thermoelasticity, the von Kármán assumption and the high-order shear deformation theory. The nonlinear governing equations are reduced for the nonlocal strain gradient-based model of nanotubes with immovable simply supported boundary conditions. The system of equations is solved for the nonlinear problems of free vibration and post-buckling of the heated tube using two-step perturbation technique and Galerkin procedure. The novel parametric examples are carried out to investigate the effect of nonlocal and length scale parameters, porosity distribution, functionally graded pattern, elastic foundations and geometrical parameters on the thermoelastic response of tubes. The obtained results highlight the importance of static/dynamic analysis of FG porous nanotubes in the thermal pre-buckling and post-buckling regimes. [ABSTRACT FROM AUTHOR]

A series of biodegradable composites, including maleic acid-grafted recycled poly(lactic acid) (g-rPLA) and chemically modified lyocell (m-lyocell), were successfully synthesized. The rPLA was obtained from waste PLA-based single-use coffee cups. The storage modulus at −20°C of g-rPLA was increased from 1920 MPa for pure PLA to 3370 MPa for 5 wt% g-rPLA/m-lyocell composites, which is more than 75% enhancement. The number-average molecular weight after photodegradation for 60 days of g-rPLA and 5 wt% g-rPLA/m-lyocell composites was decreased by about 67.12% and 26.17% as compared to the samples before photodegradation, respectively. The results of photodegradations for composites indicate that the change of number-average molecular weight after photodegradation decreased by increasing the loading of m-lyocell. This result suggests that the existence of m-lyocell improved the UV protection ability of the g-rPLA. With the enhancement of mechanical properties and UV protection ability, this work provides an appropriate approach for the applications to reuse the waste PLA-based single-use coffee cups. [ABSTRACT FROM AUTHOR]

In recent years, nickel-based composite coatings have been widely used in aerospace, petrochemical, energy industry, and other fields due to their excellent wear resistance, corrosion resistance, and thermal stability. As a surface strengthening technology, laser cladding has the advantages of low dilution rate and heat-affected zone, and has obvious advantages in the preparation of nickel-based composite coatings. In this paper, the research progress of Ni-based composite coatings prepared by laser cladding is reviewed. Firstly, the characteristics and properties of the new material system of nickel-based composite coating are summarized. Secondly, the factors affecting the properties of nickel-based composite coatings were analyzed. The influence mechanism of cladding powder and process parameters on the microstructure, mechanical properties, and mechanical properties of the coatings was discussed in detail, and the measures to improve the properties of nickel-based composite coatings were proposed. Finally, the problems faced by the preparation of nickel-based composite coatings by laser cladding are introduced, and the future development trend is prospected. This paper will help to quickly understand the development status of this field and provide reference for solving practical production problems. [ABSTRACT FROM AUTHOR]

In this study, alkali-soluble polysaccharide from Manilkara zapota (MZAP) was extracted and polysaccharide-iron complexes MZAP-Fe (III) was synthesized. Structural characterization, antioxidant and digestive properties were used to evaluate the feasibility of MZAP-Fe (III) as an iron supplement. The results showed that when the reaction temperature was 70 ℃, the pH was 9 and the addition of sodium citrate was 0.025 g, MZAP- Fe (Ⅲ) had the highest iron content (14.68 %) and its average molecular weight increased compared to MZAP. The UV and FT-IR results indicated that MZAP- Fe (Ⅲ) was formed by the carboxyl and hydroxyl groups in MZAP with the iron group to form Fe-O bonds. MZAP-Fe (III) maintained high thermal stability over the temperature range of 20°C to 450℃. When the concentration of MZAP- Fe (Ⅲ) was 1.0 mg/mL, hydroxyl radical-scavenging activity and DPPH radical scavenging activity reached 57.03 % and 82.21 %, respectively, and both were significantly higher than the antioxidant activity of MZAP. Moreover, in the simulating human digestion, MZAP- Fe (Ⅲ) was more stable than FeSO 4 and less likely to be destroyed by stomach acid. The present study demonstrated the potential of MZAP-Fe (III) as a novel iron supplement. [Display omitted] • MZAP-Fe(Ⅲ) was successfully synthesized with MZAP. • MZAP-Fe (III) possessed superior antioxidant activity than MZAP. • MZAP-Fe (III) could be better utilized in simulated in vitro digestion. [ABSTRACT FROM AUTHOR]

The caseinolytic protease (ClpP)-producing strain CHFM, isolated from Algerian goat milk, was identified as Lactiplantibacillus pentosus through 16 S rRNA sequence analysis. The optimal conditions for ClpP expression by Lpb. pentosus CHFM were determined in a modified MRS medium, where peptone was replaced with casein. The most favourable conditions were a pH of 8.0, a temperature between 25°C and 55°C, and an incubation period of 48 h. PCR screening and subsequent cloning and sequencing of the ClpP-encoding gene from the Lpb. pentosus CHFM genome revealed two conservative substitutions: threonine to serine at position 161, and aspartic acid to glutamic acid at position 182. Bioinformatic analysis indicated an instability index value of 40.51 for ClpP CHFM, suggesting stability, with an alpha-helix being the predominant secondary structure element, followed by a random coil. The aliphatic index was 97.60, indicating thermal stability. The GRAVY index was −0.23, suggesting enhanced interaction with water. The molecular weight was found to be 25.5 kDa with an isoelectric point (pI) of 4.78. The structural and docking analysis demonstrated that ClpP CHFM possesses the ability to hydrolyze αS1-casein. [Display omitted] • The growth of Lpb.pentosus CHFM at high temperatures above 50°C. • New strategy for the production of caseinolytic endopeptidase from Lpb.pentosus CHFM. • Sequencing of the ClpP CHFM-encoding gene revealed two conservative substitutions. • Docking analysis demonstrated that ClpP CHFM are capable of hydrolysing αS1-casein. [ABSTRACT FROM AUTHOR]

The room temperature ionic conductivity of polyethylene oxide (PEO)-based polymer electrolytes is low, the electrochemical window is narrow, and the mechanical strength is relatively poor. In this work, a cross-linking gel-based solid composite polymer electrolyte (CG-SCPE) was synthesized by introducing electrochemically stable carbonate-based functional groups. The synthesized CG-SCPE presents excellent tensile strength (26 MPa) and a wide electrochemical stability window (> 4.5 V vs. Li/Li+). Meanwhile, the in situ polymerization method induced by thermal heating resulted in good compatibility between electrodes/electrolytes. In addition, the assembled LiNi0.5Co0.2Mn0.3O2/CG-SCPE/Li battery exhibited satisfactory electrochemical performance. Therefore, the gel polymer electrolyte CG-SCPE with cross-linking network provides the possibility for future application of safe and high-performance solid-state lithium metal batteries. The results indicate that the introduction of cross-linking framework can simultaneously improve the mechanical strength, thermal stability, and electrochemical performance of solid polymer electrolyte. [ABSTRACT FROM AUTHOR]

Environmental pollution by toxic heavy metals is increasing at an alarming rate which demands the development of an appropriate analytical method to investigate and quantify the target analytes. In response to this call, polyaniline Titanium (IV) tungstomolybdate (PANI/TWM) nanocomposite was synthesized by incorporating polyaniline into Titanium (IV) tungstomolybdate using sol–gel method. The material was then characterized using X-ray diffraction (XRD), UV-Vis, Fourier transform infrared (FTIR), Thermogravimetric analysis (TGA-DTA), and Scanning electron microscope (SEM-EDX). It was amorphous with appreciable thermal stability as it retained 65.2% of its ion exchange capacity (IEC) up to 600 OC. It acts as a bifunctional strong acid cation exchanger with an IEC of 1.58 meq/g for Na+ ions. Moreover, the high distribution coefficients (Kd) of 1572 and 928 mL/g for Pb(II) and Co(II), respectively, indicate its potential to treat these ions in an aqueous matrix selectively. Real sample treatment with the prepared material was undertaken for binary separation of selected metal ions in column mode and practically appreciable efficiency (90.3 to 96.8%) was achieved. Therefore, the synthesized material can be considered as a promising cation exchanger to treat an environmental matrix containing toxic heavy metals. [ABSTRACT FROM AUTHOR]

The purpose of this study was to compare the efficacy of citrus peel phenolic compounds extracted using carboxylated multi -walled carbon nanotubes (MWCNT –COOH) with common synthetic antioxidants [butylhydroxyanisole (BHA) and butylhydroxytoluene (BHT)] in stabilizing sunflower oil (SO) during frying (180 ± 5 °C, 24 h). To evaluate the antioxidant activity of these compounds, total phenolic, and flavonoid contents, reducing power, ABTS scavenging activity, β -carotene bleaching ability, and 1, 1 -diphenyl - 2 - picrylhydrazyl (DPPH) radical scavenging activity were measured. Extracts were combined at various concentrations (100 -1000 ppm) with SO, and both synthetic antioxidants were standardized at 200 ppm. Thermal -oxidative stability was investigated by assessing the change in peroxide value (PV), color, free fatty acid (FFA) content, conjugated diene value (CDV), and thiobarbituric acid (TBA). Bitter orange peel extract (BPE) displayed a higher content of phenolic compounds and antioxidant activity. At 1000 ppm, it showed a lower FFA content, PV, TBA, and CDV. It can be used as an alternative to synthetic antioxidants. As a result, citrus peel phenolic compounds extracted with MWCNT –COOH can be used as preservatives in frying oils. [ABSTRACT FROM AUTHOR]

Layered structures show low thermal conductivity in the out-of-plane direction. But layer-by-layer structures coatings are rarely reported for the thermal insulation applications due to the difficulty in preparation methods. It is feasible to prepare the layer-by-layer structures from 2D materials by nanotechnology. However, achieving high ordering of nanoceramic coatings and maintaining thermal stability of layered structures after solution processes remains a significant challenge. Herein, we first reported a strategy using electrospray deposition to prepare layer-by-layer nanosheet coatings. The obtained coatings exhibit a low out-of-plane thermal conductivity. After annealing at 800 ℃, they show an ultra-low thermal conductivity of 0.07 W·m-1·k-1 due to the nano-pore structure. Furthermore, by doping large-sized metal ions, we improved the thermal stability of the layered structures from 600 ℃ to 800 ℃. The Ca 2 Nb 3 O 10 - nanosheet coatings also exhibit superior anti-corrosion and antioxidant abilities on zinc-coated iron, implying broad prospects for their application. • Layer-by-layer stacked Ca 2 Nb 3 O 10 - nanosheet coatings is applied to thermal insulation coatings. • Electrospray deposition is used to prepared layer-by-layer stacked Ca 2 Nb 3 O 10 - nanosheet coatings. • Layer structure of the coatings survives after heating at 600 °C and can be maintained up to 800 ℃ after doping K+. • The coatings show a low thermal conductivity, excellent corrosion and oxidation resistance. [ABSTRACT FROM AUTHOR]

Owing to the ferroelectric-ferroelectric phase transition and macrodomains switching during the polarization process, it is challenging to achieve both large strain with low hysteresis in ferroelectric ceramics, which severely limits their usefulness for practical applications. In this work, an effective strategy of constructing multiple local polarization configurations is designed in lead-free (100-x)Na 0.52 K 0.48 Nb 0.9 Sb 0.1 O 3 -xBaZrO 3 (NKNS-xBZ) ceramics. The incorporation of BZ regulates both the polymorphic phase transition temperature and relaxor behavior of the NKNS matrix, leading to the coexistence of nanoscaled rhombohedral, orthorhombic, and tetragonal phases with ergodic relaxor at room temperature. Consequently, these polar nanodomains with multiple symmetries significantly decrease the polarization and strain hysteresis, leading to the high electrostrictive-like strain (∼0.2 %) and extremely low strain hysteresis (∼7.4 %) with good thermal stability (strain decrease < 10 % from 20 °C to 160 °C) at x = 4. This work provides effective guidance for obtaining high strain with low hysteresis in relaxor ferroelectrics. [ABSTRACT FROM AUTHOR]

High-entropy ceramics have sparked renewed interest in compositionally complex ceramics since the first introduction in 2015. The kaleidoscopic array of compositions and structures harnessed by this idea has unlocked an unprecedented opportunity to tailor materials for specific applications, including catalysis, thermal barriers, and electrochemical energy storage. Within the family of oxides, a competition exists between rock-salt and spinel structures. The rock-salt structure is highly symmetrical, consisting of a single cation sublattice, while the spinel structure offers more flexibility to accommodate various cations in two distinct sublattices. Herein, we aimed at stabilizing and expanding the thermal stability range of the spinel-structured oxide, successfully synthesizing novel, single-phase, compositionally complex materials by capitalizing on entropy stabilization, all while avoiding the ubiquitous use of nickel and chrome, notorious for their negative environmental impact. The right combination of cations resulted in the synthesis of a seven-metal oxide that is thermally stable up to the remarkable temperature of 1473 K. [ABSTRACT FROM AUTHOR]

Broadband near-infrared (NIR) phosphor-converted light-emitting diodes (pc-LEDs) have become important as new NIR light sources in NIR spectroscopy and NIR imaging techniques. However, currently developed broadband NIR phosphors commonly suffer from weak emission and poor thermal stability. In this work, a series of Gd 3 Lu 2 Ga 3 O 12 : Cr3+ phosphors were synthesized via high-temperature solid-state reaction. Under 460 nm excitation, the phosphors exhibit an intense emission spanning from 650 to 1150 nm with a full width at half maximum (FWHM) of 122 nm. After introducing Yb3+ as a co-dopant, the emission of the phosphor has been broadened greatly. Interestingly, the studied phosphors demonstrate super high thermal stability in a wide temperature range of 35–560 K, with the integrated emission intensity fluctuating within 10 %. At 435 K, the emission intensity of Gd 3 Lu 2 Ga 3 O 12 : 0.03Cr3+ remains 99.5 % and Gd 3 Lu 2 Ga 3 O 12 : 0.03Cr3+, 0.01 Yb3+ keeps 102.7 % of the initial intensity at room temperature. These NIR phosphors have been encapsulated with a common commercial 460 nm blue LED chip to fabricate a pc-LED device. The NIR output power of the device reaches 23.93 mW@100 mA, with a photoelectric conversion efficiency of 9.81 % at 20 mA current. The applications of the prepared NIR light source in night vision, and bioimaging have been demonstrated. The results show that these Cr3+/Yb3+ doped garnet phosphors can be effectively used in NIR light sources. [ABSTRACT FROM AUTHOR]

Due to the adoption of fluorescent powder encapsulated by organic resin, commercial light emitting diodes (LEDs) suffer from low thermal stability and poor light quality under high temperature, and luminescent glass is one of the effective ways to solve this problem. A series of borosilicate (B 2 O 3 –SiO 2 –Al 2 O 3 –PbO-Dy 2 O 3 –Eu 2 O 3 , marked as BSAP: DyEu) was prepared by the gas suspension technique. The basic characterization test indicate that the prepared glass has excellent thermal stability and stable structure. The optical properties of the luminescent glass were investigated in detail. By changing the Eu3+ doping amount, the Dy3+/Eu3+ co-doped glass can realize warm white light emission. The temperature-variable fluorescence spectra of BASP: Dy1.25Eu1.0 were analyzed, and the glass can produce strong warm white light emission in a wide temperature range. At 700 K, the luminous intensity of the glass remains above 38.49 % of the room temperature, and the chroma shift ΔC = 8.57 × 10−3. In addition, the w- LED device based on commercial GaN chip and BSAP: DyEu glass realizes warm white light output with excellent correlated color temperature (3063 K) and high color rendering index (90.3). The analysis shows that Dy3+/Eu3+ co-doped borosilicate glass can be used as a candidate material for w- LED applications. [ABSTRACT FROM AUTHOR]

In recent decades, numerous red phosphors have been designed and developed. Nevertheless, many of them are unsatisfactory due to their low brightness and poor thermal stability. Look at these shortcomings; present study reports on Eu3+ doped Y 2 Si 2 O 7 (YPS) phosphors, synthesized through low temperature based urea assisted gel-combustion method. Comprehensive investigations were conducted on phase purity, luminous characteristics, energy transfer mechanism, quantum efficacy, morphology, elemental makeup, band gap and thermal stability. XRD analysis was employed to verify the preparation of Y 2 Si 2 O 7 matrix with triclinic structure (P-1 space group). Morphology and elemental investigations of the fabricated materials was evaluated via TEM and EDX techniques respectively. Under the illumination at 393 nm, the most strong emission band is shown in PL spectra at 613 nm (electric dipole 5D 0 →7F 2 transition). Additionally, the dipole-quadrupole (d-q) interaction was found to be the predominant route of energy transfer among nearby Eu3+ ions and it was concluded that 3 mol % was the optimal doping concentration of Eu3+ ions. The Judd-Ofelt (J-O) theory was used for current phosphors in order to establish their Ω 2 and Ω 4 with other radiative parameters. The assessment of thermal stability yielded highly promising results with activation energy of 0.241 eV. Present research indicates that Y 2 Si 2 O 7 :Eu3+ is a promising candidate of red emitting phosphor for white light-emitting diodes. [Display omitted] • Gel-combustion derived Eu3+ doped Y 2 Si 2 O 7 nanophosphors were crystallized into triclinic symmetry with P–1 space group. • Dominance of electric dipole 5D 0 →7F 2 transition at 613 nm was observed which define the red color of synthesized nanophosphors. • The luminous thermal stability revealed 69.4 % of luminescence at 498 K with activation energy of 0.241 eV. • Colorimetric investigation of the synthesized Y 2 Si 2 O 7 :Eu3+ nanophosphors validate their applicability in white light applications. [ABSTRACT FROM AUTHOR]

The preparation and characterization of composite materials composed of polypropylene (PP) as the base mixed with halloysite nanotubes (HNT) at various weight percentages (0.5, 1.5, and 3 wt.%) using a melt extrusion method operated at a temperature between 190 °C and 200 °C is described. The impact of the addition of the HNT filler on the PP nanocomposites was investigated based on the thermal and mechanical properties. The thermal characterization was conducted by differential scanning calorimetry (DSC). Significant increases in the rheological properties were observed with the addition of a high content of HNTs. The water absorption decreased with increasing HNT. The SEM micrographs showed that the HNT fillers were homogeneously dispersed throughout the entire PP matrix. [ABSTRACT FROM AUTHOR]