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The concurrent enhancement of toughness, electrical conductivity, and thermal stability in polycrystalline diamond composites represents a formidable challenge. Here, a novel diamond-TiC composites (referred to as DTC) with high fracture toughness and conductivity were synthesized through a high-temperature and high-pressure reaction sintering process utilizing two precursors: diamond mixtures containing TiH 2 and Ti-coated diamonds. On the one hand, the inherent bonding and encasing of TiC onto the diamond matrix form a heterogeneous structure, providing high strength and excellent fracture toughness up to 11.6 MPa·m1/2. On the other hand, the established oxygen barrier and current pathway offer a thermal stability of 765 °C and high conductivity up to 837 S·m−1. Remarkably, this rare combination of mechanical, electrical, and thermal properties has been realized within a single material under relatively moderate sintering conditions, thus positioning diamond-TiC composites as a promising ceramic for electrical applications in high-stress environments. [ABSTRACT FROM AUTHOR]

Ceramic fibers are an important thermal insulation material that are not only widely used in extreme conditions, but also play an important role in energy conservation and energy efficiency for sustainable development. However, the practical application of conventional ceramic fibers has a high thermal conductivity in high-temperature environments, which hinders their widespread application. Here, a novel lamellar structured porous SiTiOC/C composite ceramic materials was designed and prepared with excellent thermal insulating properties. The unique microstructure endowed the porous SiTiOC/C composite ceramic materials with a high IR refractive index (93.81%) and an ultra-low thermal conductivity (0.0562 W·m−1 K−1 at 600 ℃). In addition, the porous SiTiOC/C composite ceramic materials not only exhibited excellent mechanical properties (4.46 MPa at 800 ℃), but also demonstrated impressive oxidation resistance and thermal stability. In summary, the proposed porous SiTiOC/C composite ceramic materials provide a reference for the development of high-temperature insulation with good mechanical properties. [ABSTRACT FROM AUTHOR]

Dy 2 O 3 –Sm 2 O 3 co-doped transparent glass ceramics (GCs) containing NaBi(WO 4) 2 crystalline phase were prepared by melt-curing-crystallization method. The optimal heat treatment condition is 580 °C/2 h. The optimum incorporation concentration of Dy 2 O 3 is 0.4%, exceeding which a quenching phenomenon dominated by quadrupole-quadrupole interactions emerges. Meanwhile, when the concentration of Dy 2 O 3 was fixed, the chromaticity coordinate of the sample moved the cool white light region to the warm white light region as the concentration of Sm 2 O 3 increased. The temperature-dependent emission spectra of the 0.4% Dy 2 O 3 -0.7% Sm 2 O 3 co-doped GC samples show that emission intensity at 575 nm at 185 °C still reaches 80% of the room temperature. The thermal quenching activation energy was 0.1537 eV and the activation energy after the addition of Mo6+ was 0.1957 eV. This study indicates that Dy 2 O 3 –Sm 2 O 3 co-doped GCs containing NaBi(WO 4) 2 crystalline phase can achieve light-color tunable emission, which is potentially valuable for solid-state color rendering and illumination applications. [ABSTRACT FROM AUTHOR]

In this study, a highly dense GdB 6 bulk ceramic material was fabricated using one-step in-situ reaction spark plasma sintering technology. The sample with a relative density of 96.7 % and a purity of 96.9 wt% was successfully obtained by sintering at 1800 °C for 30 min under a uniaxial pressure of 50 MPa. The Vickers hardness, elastic modulus and fracture toughness of the as-obtained GdB 6 bulk ceramics were 18.9 GPa, 209 GPa and 1.6 MPa·m1/2, respectively. The thermal conductivity of GdB 6 at room temperature was 28.68 W·m−1·K−1, 70 % of which was mainly attributed to phonon vibration, while the remaining 30 % to the electrical thermal conductivity. In addition, the as-obtained GdB 6 ceramics showed no phase transformation after heat treatment at a relatively high temperature of 2100 °C for 20 min in Ar atmosphere. The highly covalent octahedral boron framework played a critical role in maintaining the phase stability of the GdB 6 crystal lattice. This suggested that GdB 6 ceramics could be used as potential ultra-high temperature ceramics for aerospace applications and high-power vacuum electronic devices operated at high temperatures. [ABSTRACT FROM AUTHOR]

The ZrO 2 fiber paper exhibits excellent thermal insulation properties, however, its limited mechanical strength and insufficient thermal stability hinder its widespread applications. The composite fiber papers, using mullite fibers possessing a high aspect ratio and exceptional thermal stability combined with ZrO 2 fibers, were fabricated via a vacuum-assisted filtration method. This method involved the successive stacking of composite fibers with alumina sol, using vacuum-induced directed water flow to create a layered structure reminiscent of nacre. The layered structure of the nacre, which demonstrates remarkable strength and hardness, has also served as a source of inspiration for the architectural design of the fiber paper. The tensile strength of pure ZrO 2 fiber paper was significantly enhanced by the addition of 7 wt% mullite fibers, resulting in a remarkable increase to 0.1805 kN/m. The paper exhibited exceptional resistance to bending, maintaining 96 % of its bending strength even after undergoing 100 cycles. The thermal shrinkage of the composite paper, containing 15 wt% mullite fibers, was reduced from 17.75 % observed in pure ZrO 2 fiber paper to a mere 1.32 % after undergoing heat treatment at a temperature of 1300 °C for 2 h. The composite paper, measuring 5 mm in thickness and consisting of 7 wt% compositions, displayed exceptional thermal insulation properties when exposed to a hot side temperature of 1370 °C. It effectively insulated temperatures up to approximately 1000 °C. [ABSTRACT FROM AUTHOR]

Improvement in thermal stability is especially important for the oxide/oxide composites, which are widely applied at high temperatures. Herein, the continuous alumina fiber reinforced alumina matrix (Al 2 O 3 /Al 2 O 3) composites were fabricated at 1200–1400 °C using Al 2 O 3 powders with a mean size of 0.6 μm. The Al 2 O 3 /Al 2 O 3 composite fabricated at 1300 °C achieved a high flexural strength of 392.9 ± 20.1 MPa and a high interlaminar shear strength of 20.6 ± 1.0 MPa. After exposure at 1000 °C for 100 h and 1400 °C for 10 min, the 1300 °C fabricated Al 2 O 3 /Al 2 O 3 composite showed no significant reduction in mechanical properties. A slight decrease in mechanical properties was observed after aging at 1200 °C for 100 h. The high strength retention after the heat treatment benefited from the coarse Al 2 O 3 powders, which could not be easily sintered at high temperatures. This work can expand the selection of the Al 2 O 3 /Al 2 O 3 composites for potential applications at service temperatures as high as 1400 °C for a short term. [ABSTRACT FROM AUTHOR]

Current highly integrated devices require heat interface materials with excellent heat conductivity. A simple approach was employed to synthesize thermally conductive and outstanding thermal stability nanocomposite. Calcium carbonate nanoparticles (nano CaCO 3) reinforced with reduced graphene oxide (rGO) nanoparticles (rGO/CaCO 3) are synthesized using a novel process, and the effect of rGO in CaCO 3 structure is examined by Field Emission Scanning Electron Microscope, X-ray diffraction, TGA-DTA, and thermal conductivity. The experimental results show that adding rGO resulted in higher crystallinity and thermal stability. As the wt.% of rGO increases from 1 to 5%, the crystallite size was suppressed by 21.06%, 27.39%, 32.48%, 41.5%, and 45.30%, respectively, compared to the pure nano-CaCO 3. Additionally, rGO enhances the thermal conductivity by 35.31% and thermal diffusivity to 1.834 mm2/s by adding 5% rGO. [ABSTRACT FROM AUTHOR]

Melt-quenching techniques were employed to produce a series of Nd 2 O 3 doped Al 2 O 3 –Na 2 O–WO 3 –B 2 O 3 glasses. Structure, optical, and thermal properties were investigated to illustrate the effectiveness of the Nd3+ ions in enhancement performance and analyze their behaviour. Nd 2 O 3 demonstrably contributed to the composite, as evidenced by evaluating all features. The density marginally rises with the addition of Nd 2 O 3 instead of B 2 O 3. The relevant physical characteristics had been calculated. The structure was analyzed by FTIR measurement and identified the vibration modes of varied concentrations. From FTIR spectra, N 4 values were reckoned, and the conversion of the network structure unit from BO 3 to BO 4 was verified. Numerous significant peaks have been caught in the absorption bands of the UV–Vis–NIR measurement. Optical bandgap and band tail are determined. DSC measurements were utilized to identify the thermal characteristics. As Nd3+ ions increased, glass thermal stability improved. Overall, the Nd3+ ion modifier rule was realized. [ABSTRACT FROM AUTHOR]

Entropy plays a crucial role in designing new functional materials or enhancing material performance. The design of high entropy ceramics (HECs) introduces a larger composition space, thus the understanding of the correlation between the composition, entropy effect, and the performance of HECs is becoming increasingly important. In this work, to pursue superior properties, a series of CeNbO 4 -based solid solution ceramics with a maximum of 9 species cations in a single sublattice were synthesized by using high entropy configuration strategy. The interaction of composition, size disorder, and configurational entropy on the properties of HECs was emphasized. The potential conflict between high resistivity and low material constant of thermosensitive ceramics was overcome and thus achieving excellent thermal sensitivity properties having an extremely wide temperature range from room temperature to 1623 K and long-term high-temperature stability. This will bring innovative prospects for the design and application of high-temperature functional ceramics. [ABSTRACT FROM AUTHOR]

This study explored the effect of diverse coagulants (glucono-δ-lactone (GDL), gypsum (GYP), microbial transglutaminase (MTGase), and white vinegar (WVG)) on microstructure, quality, and digestion properties of tofu. The four kinds of tofu were significantly different in their structure, composition, and digestibility. Tofu coagulated with MTGase had the highest springiness and cohesiveness while GDL tofu had the highest enthalpy (6.54 J/g). However, the WVG and GYP groups outperformed others in terms of thermodynamic, and digestion properties. The WVG group exhibited the highest nitrogen release (84.3%), water content, denaturation temperature, and the highest free-SH content but the lowest S-S content. Compared to WVG, the GYP group had the highest ash content, hardness, and chewiness. Results demonstrated that the tofu prepared by WVG and GYP show high digestibility. Meanwhile, the former has better thermal properties and the latter has better texture properties. [Display omitted] • Tofu coagulated with GYP and WVG exhibited higher digestibility than others. • The WVG group showed the highest thermal stability, digestibility, and water content. • Compared with WVG,the GYP tofu had the highest ash content, hardness, and chewiness • Tofu coagulated with MTGase had the highest springiness and cohesiveness. [ABSTRACT FROM AUTHOR]

Due to their distinct physicochemical characteristics and outstanding biocompatibility, carbon quantum dots have shown to offer enormous potential in the field of temperature sensing. However, there is still much to learn about the mechanism underlying carbon quantum dots' thermal sensing capabilities, and developing incredibly precise thermometers based on it is still an enormous obstacle. Herein, we successfully fabricated carbon quantum dots with variable luminescence wavelength and temperature-sensitive properties by adjusting the ingredients to modify the composition of functional groups (-NH 2 , -OH, -COOH and -CH 2 OH) on the surface of quantum dots in a simple hydrothermal synthesis process, followed by encapsulation with polyvinyl alcohol (PVA). Subsequently, structural/optical characterisation and temperature-dependent studies were utilized for investigations into the quantum dot fluorescence mechanisms as well as the thermal sensing characteristics connected to surface functional groups, respectively. Notably, the designed red-emitting methylenated carbon quantum dot film probe displayed more linear segmented temperature sensing properties (R2>0.99), a wider temperature applicability range (20–160 °C), and high temperature reversibility (20–80 °C, at least 4 cycles). Finally, the mechanism by which functional groups affect the thermal characteristics of carbon quantum dots was addressed, and we hypothesized that intramolecular and intermolecular hydrogen bonding interactions are important factors affecting the thermal properties of carbon dots. This work presents great promise and theoretical guidance for the development of highly reliable carbon quantum dot temperature sensing systems. [Display omitted] • Carbon quantum dots/PVA probe was fabricated. • Optimal optical behavior & temperature response by tuning surface functional groups. • The probe presented outstanding temperature dependence and higher thermal stability. • Luminescence and thermal sensing mechanisms influenced by surface functional groups. • The probe exemplified the potential of CQDs as luminescent temperature sensors. [ABSTRACT FROM AUTHOR]

• A high energy density (W) value of 7.82 J/cm3 with energy storage efficiency (η) of 81.8% is acquired simultaneously. • A splendid thermal stability (Δ W rec : ∼ 2.9 %, Δ η : ∼ 3.9 %) within the temperature range of 20 ℃-100 ℃. • Further analysis of the influence of NaNbO 3 in KNN ceramics is investigated on the phase structure and microstructure. • Detailed discussions of evolution of domain structure and its influence on the energy storage properties after doping NaNbO 3. The advancement of high energy storage properties and outstanding temperature stability ceramics plays a decisive role in the field of pulsed power systems. The multi-component optimization strategy is conducted by introducing Li+, Bi(Ni 1/2 Zr 1/2)O 3 and NaNbO 3 into KNN-based ceramics. An excellent energy storage (W) of 7.82 J/cm3 along with a large efficiency (η) of 81.8 % is achieved at the breakdown strength (BDS) of 500 kV/cm for the ceramics. Simultaneously, the remarkable energy storage thermal stability (Δ W rec : ∼ 2.9 %, Δ η : ∼ 3.9 %) is acquired in the range from 20 ℃ to 100 ℃. The splendid charging-discharging performances (discharge energy density W d = 1.78 J/cm3, current density C D = 1376 A/cm2, power density P D = 124 MW/cm3) are also realized in the ceramics after doping. By investigating the evolution of crystal structure and domain structure, complex impedance and first-principle calculations, the internal mechanism of obtaining superior energy storage properties is analyzed. Thus, this research proves that the ceramics can effectively broaden the temperature range of the applications for the pulsed power systems while maintaining high energy storage properties, which offers a valuable approach for the improvement of dielectric capacitors. [ABSTRACT FROM AUTHOR]

In this work, Cu-1.5 wt%Y (Cu-Y) and Cu-0.75 wt%Y-0.75 wt%La (Cu-Y-La) were prepared by mechanical alloying combined with spark plasm sintering and hot rolling, followed with annealing at different temperatures. The effects of the introduction of La and annealing temperatures on the microstructures, mechanical properties, electrical conductivity and thermal stability of Cu-Y alloys were investigated. Both Cu-Y and Cu-Y-La obtain the heterogeneous mixed grain structures composed of coarse grains and fine grains, and oxide nanoparticles are uniformly dispersed in Cu matrix. With the introduction of La, the grains and oxide nanoparticles are refined, and LaYO 3 nanoparticles with the coherent interfacial structure can be observed in Cu-Y-La. After annealing at 500 ℃, both Cu-Y and Cu-Y-La obtain the most excellent comprehensive tensile properties and highest electrical conductivity (63 %IACS for Cu-Y and 62 %IACS for Cu-Y-La). Benefited from effectively enhanced grain boundary strengthening and particle strengthening mechanisms induced by the combination effect of La and Y, Cu-Y-La shows higher strength than that of Cu-Y (after annealing at 500 ℃, 244 MPa of yield strength for Cu-Y and 300 MPa for Cu-Y-La). Meanwhile, benefited from improved dynamics stability of the Cu matrix induced by significantly refined precipitates and the formation of LaYO 3 nanoparticles with the coherent interfacial structure after introducing La, the better softening resistance is achieved by Cu-Y-La in comparsion with Cu-Y, and almost 100 ℃ improvement of the softening temperature is achieved (966 ℃ for Cu-Y-La and 870 ℃ for Cu-Y). • A novel system of Cu-Y-La alloy for the field of ITER is designed and prepared. • Effects of heat treatment on microstructure and properties of Cu alloys reinforced by rare earth elements are studied. • The significant improvement of mechanical property of Cu-Y alloy is achieved through the combination effect of Y and La. • The softening resistance of Cu-Y alloy is successfully improved through the combination effect of Y and La. [ABSTRACT FROM AUTHOR]

• Lesser mealworm protein gel (LMPG): a potential vitamin B 12 encapsulant. • Improved LMPG by a synergy of transglutaminase (TGase) and ultrasound (US) • Enhanced thermal stability and gelling in TGase-induced LMPG after 60 min-US. • A high controlled release rate of cobalamin under in vitro simulated digestion. • Developing new gluten-free bread products with vitamin B 12 -loaded gel powders. A combined approach of microbial transglutaminase (MTGase) crosslinking and high-intensity ultrasound (HIU) was implemented to improve the physicochemical, rheological, structural, and thermal properties, as well as the targeted release of vitamin B 12 of lesser mealworm protein isolate (LMPI)-based gels. Prolonging HIU to 60 min significantly reduced LMPIs' size, polydispersity, zeta-potential, and fluorescence intensity while increasing surface hydrophobicity, free amino (FAGs), and sulfhydryl (FSGs) groups. The MTGase-catalyzed LMPI gels effectively decreased the content of FAGs and FSGs. LMPI gels from 60 and 75 min HIU and MTGase catalysis exhibited a shear-thinning flow behavior, superior thermal stability, and improved water retention and gel strength with the most controlled release of vitamin B 12 during in vitro simulated gastrointestinal digestion. Incorporating freeze-dried gel powders from 60 min HIU-treated MTGase-catalyzed LMPI and pea protein isolate into the dough of a new gluten-free bread improved physicochemical, textural, and sensory properties, with notable vitamin B 12 retention rate. [ABSTRACT FROM AUTHOR]

[Display omitted] • Oils improved emulsion gel properties of PSE-like protein isolate (PPI). • The added sunflower oil to PPI enhanced protein thermal stability. • PPI-sunflower oil gel has the highest water binding capacity. • Vegetable oils enhanced secondary structural stability of PPI. To enhance the gel properties of PSE (pale, soft, and exudative)-like chicken meat protein isolate (PPI), the effect of peanut, corn, soybean, and sunflower oils on the gel properties of PPI emulsion gels was investigated. Vegetable oils improved emulsion stability and gel strength and enhanced viscosity and elasticity. The gel strength of the PPI–sunflower oil emulsion gel increased by 163.30 %. The thermal denaturation temperature and enthalpy values were increased. They decreased the particle size of PPI emulsion (P < 0.05) and changed the three-dimensional network structure of PPI emulsion gels from reticular to sheet with a smooth surface and pore-reduced lamellar. They elevated the content of immobile water PPI emulsion gels, decreased the α-helix and β-turn, and increased the β-sheet and random coil. Vegetable oil improved the gel properties of PPI in the following order: sunflower oil > soybean oil > corn oil ≈ peanut oil > control group. [ABSTRACT FROM AUTHOR]

Polybenzoxazine-imine hybrid resins with good thermal and mechanical properties, as well as excellent shape memory and recycling properties, were prepared from bio-based benzoxazine synthesized from vanillin and a biobased diamine derived from furylamine and benzaldehyde (V-bfa), terephthalaldehyde (TA), and Jeffamine T403. The films have good thermal, mechanical, and recycling properties, influenced by the ratio of V-bfa and TA. The higher the percentage of V-bfa, the better the thermal properties, thermal stability, and shape memory properties of the films, unfortunately, the film with 100 % V-bfa content (Btt-10) exhibited brittleness and could not be fully recovered. Surprisingly, the film with half the amount of v-bfa (Btt-11) has excellent shape memory properties, unfolding over 90° in just 12 s after folding and returning to its original shape in 20 s, moreover, the rate of shape fixation (R f) and the rate of shape recovery (R r) is 90.56 % and 95.56 %, respectively. Meanwhile, the thermal, mechanical, and shape memory properties of the film were also not damaged in any way even after three recycling cycles. Therefore, Btts film are very low carbon and environmentally friendly, complying with the requirement to reduce carbon emissions. [Display omitted] • Bio-benzoxazine-imine hybrid resins with good thermal and mechanical properties are prepared. • The films exhibit excellent shape memory properties. • The film shows stable thermal, thermal stability and mechanical properties even after 3 cycles of recycling. [ABSTRACT FROM AUTHOR]

It has been always a daunting task to develop thermal systems with a wide range of thermochemical properties and high stability. It presents a significant challenge, especially when aiming to utilize them for heat storage and transfer applications. In this regard, the thermal characteristics and thermal stability behaviour of molten salt mixture as a heat transfer fluid (HTF) at high temperatures were explored. A novel ternary eutectic salt mixture (base mixture) made of cuprous chloride (CuCl), potassium chloride (KCl) and sodium chloride (NaCl) was investigated as HTF for thermal energy storage (TES) system with a range up to 653 °C in a concentrated solar power (CSP) plant. To extend the temperature span and stability, the effect of an additive was investigated. Different compositions were studied in detail concerning the properties and stability regarding the additive. The molten salt with 7 % CaCl 2 additive improved thermal stability and operating temperature from 653 °C to 700 °C. The transport characteristics and thermal stability of the eutectic mixture with and without the additive were measured by high-temperature thermal analyzers. The results indicated that the melting temperature decreased and the average specific heat capacity considerably increased with the addition of CaCl 2 additive compared to the ternary chloride base mixture. As the temperature increased, the eutectic salt mixture exhibited a reduction in viscosity and density. The viscosity and density of the salt mixture with and without the additive were almost uniform at 700 °C. The average thermal conductivity of the ternary salt mixture with and without additives was 0.72 W/(m°C) which is much more than that of Solar and Hitec salts. In a 100 h experiment of long-period isothermal stability, the eutectic salt mixture showed less than 4 % weight loss at 700 °C. It was defined as the highest operating temperature at which the eutectic salt mixture remained stable. The stability and recyclability of the salt mixture were confirmed through the short-period stability test. The effect of the CaCl 2 additive on thermal stability of base salt mixture was analyzed by X-ray Diffraction (XRD) and X-ray Photoelectron Spectroscopy (XPS) techniques. According to the results, this novel eutectic salt mixture had outstanding thermal stability up to 700 °C and could be employed as a viable TES material in CSP plants. • CuCl–KCl–NaCl eutectic mixture with a low melting point (144 °C) and high thermal stability (658 °C) was investigated. • Addition of 7 % CaCl 2 reduced the melting point to 138.3 °C and improved thermal stability to 700 °C. • The proposed salt mixture has an excellent operating temperature range of 200–700 °C. • The long and short period thermal stability exhibited excellent stability and recyclability up to 700 °C. [ABSTRACT FROM AUTHOR]

The temperature range within which phase change materials (PCM) in water emulsions can effectively function is limited to 0–100 °C. In contrast, non-aqueous emulsions offer a broader temperature range for heat storage and transfers, along with greater chemical stability. This research involved the preparation of a PCM in silicone oil phase change emulsion using the emulsion inversion point (EIP) method as an alternative to high-energy methods which known for their high energy consumption and low efficiency. The emulsion was produced by gradually adding silicone oil to a mixture of lauric acid and surfactant under low-speed stirring. The study focused on assessing dispersion stability and thermal properties of emulsions with varying PCM concentrations. Results showed that similar droplet sizes can be achieved compared to high-energy methods, with average droplet sizes ranging from 5.21 to 6.89 μm for emulsions containing 5%–20% lauric acid. The phase change enthalpy of the emulsions aligned with theoretical values, showing a supercooling below 3.0 °C when PCM concentration was between 10 and 20%. Additionally, the viscosity of the emulsions decreased as the PCM concentration increased. Moreover, the addition of nanoparticles increased thermal conductivity by 19.8%, with energy storage efficiency remaining at 97.3% after thermal cycling. The emulsions also demonstrated reduced pumping power requirements by 87.3% and 99.4% at 25 °C and 50 °C, respectively, compared to the base fluid, making them promising candidates for enhancing the utilization of renewable energy sources including solar energy. • Fatty acid in oil emulsions exhibited great storage stability for 5 months. • Viscosity of the emulsions decreased as mass fraction of PCM increased. • Inclusion of nanoparticles enhanced thermal conductivity of emulsion by 19.8%. • Energy storage efficiency remained 97.3% after 100 thermal cycles. • Pumping power reduced by 99.4% for the 20% emulsion compared to base fluid. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new type of FSCPCMs with a wide phase change temperature range were designed. • The latent heat of the prepared FSCPCMs could reach 142.5 J/g. • The FSCPCMs exhibit good thermal conductivity and thermal stability. Phase change materials (PCMs) with wide phase change temperature range, high latent heat, good thermal conductivity, and shape stability are essential for applications such as solar energy conservation and thermal management of electronic devices. Form-stable composite PCMs (FSCPCMs) with a broad phase change temperature range of 18–65 °C were successfully developed by using a mixture of eicosane and paraffin mixture along with cross-linking polyurethane as PCM, expanded graphite as thermally conductive filler and supporting material. The prepared FSCPCMs demonstrated excellent thermal stability and thermal conductivity with a latent heat up to 142.5 J/g. In conclusion, the synthesized FSCPCMs exhibit promising potential for practical applications in thermal energy storage. [ABSTRACT FROM AUTHOR]

A series of phthalonitrile resins were synthesized through innovative reactions between compounds derived from benzyl alcohol and nitro functionalities. The synthesis commenced with the reaction of specific alcohols (4-hydroxybenzyl alcohol, vanillyl alcohol, and 1,4-benzenedimethanol) with 4-nitrophthalonitrile, resulting in the formation of three phthalonitrile monomers. These monomers were then cured using 4,4′-diaminodiphenyl ether as a curing agent, resulting in the phthalonitrile resins, namely BCDPN, XCDPN, and DBDPN. The investigation revealed that these resins possessed remarkable properties, particularly in terms of thermal stability and dynamic mechanical behavior. Notably, BCDPN exhibited superior thermal stability, achieving a T d10 % of 534 °C. XCDPN and DBDPN demonstrated outstanding dynamic mechanical properties, characterized by a storage modulus exceeding 3400 MPa. The synthesis approach, leveraging compounds derived from benzyl alcohol and nitro reactions, not only broadens the scope of raw materials but also offers novel and alternative preparation strategies for phthalonitrile resins. This study enhances the understanding of the curing behavior and thermal properties of these resins, providing valuable insights into their potential applications in high-performance polymer materials. [Display omitted] • Synthesis of phthalonitrile resin uses compounds from benzyl alcohol & nitro reaction, expanding raw material sources. • Great thermal stability & dynamic mechanical props in BCDPN, XCDPN, DBDPN resins. • Curing behavior & thermal props insights for potential in high-performance polymer materials. [ABSTRACT FROM AUTHOR]

Obtaining lignin-based graphite-like microcrystallites at a relatively low carbonization temperature is still very challenging. In this work, we report a new method based on condensed structures, for regulating graphite-like microcrystalline structures via the incorporation of 4,4′-diphenylmethane diisocyanate (MDI) into the main structure of lignin. The effects of MDI on the thermal properties of lignin and the graphite-like microcrystalline structure of lignin-based ultrafine carbon fibers were extensively studied and investigated. The incorporation of MDI decreased the thermal stability of lignin, increased the carbon yield and enhanced the formation of graphite-like microcrystallites, which are beneficial for reducing energy consumption during the preparation of lignin-based carbon fibers. The modified lignin-based ultrafine carbon fibers (M-LCFs) demonstrated satisfactory electrochemical performance, including high specific capacitance, low charge transfer resistance, and good cycle performance. The M-LCFs-3/2 electrode had a specific capacitance of 241.3 F g−1 at a current density of 0.5 A g−1, and a residual ratio of 90.2 % after 2000 charge and discharge cycles. This study provides a new approach to control the graphite-like microcrystalline structure and electrochemical performance while also optimizing the temperature. • Lignin-based carbon fiber with graphite structure was prepared at a low temperature. • Condensed structure facilitate the formation of graphite-like structure. • MDI decreased the thermal stability of lignin and energy consumption of carbon fiber. • MDI-modified lignin shows fascinating application in supercapacitor. [ABSTRACT FROM AUTHOR]

• Quaternary chalcogenide glassy systems have been prepared by melt quenching method. • Compositional dependence of various thermal parameters has been studied by deploying DSC analysis. • The Meyer-Neldel rule is used to explain AC conduction mechanism. • Mott's and Greaves VRH model is used to investigate DC conduction mechanism. • Electrical conduction relaxation has been analyzed by using Pan and Ghosh model. Tunability of thermal, and electrical characteristics of Sb x Se 50-x Sn 20 Te 30 (x = 2, 4, 6, and 8 at. %) bulk glass systems with varying doping concentrations are the major objective of this study. The melt quenching technique has been employed to synthesize the samples. Various thermal parameters have been inspected by using DSC measurements. The effect of Sb addition on the glass transition temperature (T g), crystallization temperature (T c), peak crystallization temperature (T p), and melting temperature (T m) have been observed from DSC thermograms. The dependence of Tg, Tc, Tp, and Tm on the heating rate has been measured. The thermal analysis is performed under non-isothermal conditions at heating rates of 5, 10, 15, and 20 K/min. The activation energies for the glass transition temperature are estimated by using the Kissinger method and are found to decrease from (211.21-168.85) KJ.mol−1. Thermal stability and glass forming ability for all glassy compositions have been examined in terms of Hruby's parameter. In addition, electrical conductivity mechanisms over vast temperature and frequency ranges are analyzed. The DC conductivity mechanism has been analyzed by deploying Mott and Greaves's variable range hopping model, while the AC conductivity mechanism has been analyzed by deploying the modified correlated barrier hopping model. AC conductivity scaling property has been examined by using the Pan and Ghosh model. The influence of Sb addition has been observed as the DC and AC conductivity increases with the increase of doping concentration. [ABSTRACT FROM AUTHOR]

Two new MOFs were prepared under solvothermal conditions using 5-aminotetrazole as a ligand with high thermal stability, good detonation properties and low sensitivity, which are potentially safe energetic materials. [Display omitted] • Two new MOFs were prepared under solvothermal conditions using 5-aminotetrazole as the high-nitrogen energetic ligand. • Compound 1 possess an ABX 3 -type perovskite-like structure, whereas compound 2 forms a two-dimensional layer. • Both compounds demonstrated high thermal stabilities, good detonation properties and low sensitivity. Metal-Organic Frameworks (MOFs) have recently gained prominence as a novel class of energetic materials, owing to their systematic design and the ability to fine-tune properties such as energy content, sensitivity, and thermal stability. In this study, two new MOFs namely Cd(5-AT) 3 NH 2 (CH 3) 2 + (1) and Zn(5-AT)(AMP) (2) (5-HAT = 5-aminotetrazole) were prepared under solvothermal conditions using 5-aminotetrazole as the high-nitrogen energetic ligand. X-ray single crystal diffraction analysis revealed that compound 1 possess an ABX 3 -type perovskite-like structure, whereas compound 2 forms a two-dimensional layer. The high thermal stability of both compounds were confirmed through thermogravimetry (TG) and differential scanning calorimetry (DSC). Their constant-volume combustion heat (Δ c U) was first determined by oxygen-bomb calorimetry and then the standard molar enthalpy of formation (Δ f Ho) was calculated. Furthermore, both compounds demonstrated great detonation properties and low sensitivity, showing their potential application as new explosive materials (EMs). [ABSTRACT FROM AUTHOR]

This work reports a composite film using (3-Aminopropyl)triethoxysilane-modified boron nitride nanosheets (BNNS) incorporated in the aramid nanofibers (ANF) network via sol–gel method. High-resolution TEM, SEM, XPS, and XRD outcomes confirmed the imitation pearl layered structure—BNNSs as thermal conductive fillers were layer-by-layer overlapped on ANF. The reasonable coordination between interfaces and fillers stimulated the thermal conductivity (35.4 W/(m·k)) of composite film i.e., 338.43% higher than that of ANF. The composite film exhibited good cyclic thermal stability, high tensile strength (65.9 MPa), and high volume resistivity (2.424×1015 Ω∙cm). [Display omitted] • BNNS@APTES/ANF with imitation pearl layered structure was prepared via sol–gel method. • BNNS as thermal conductive fillers were layer-by-layer overlapped on the ANF. • High thermal conductivity of BNNS@APTES/ANF was 35.4 W/(m·k) higher than pure ANF. • BNNS@APTES/ANF exhibited excellent tensile property and high volume resistivity. • The thermal conductivity of BNNS@APTES/ANF did not decay during 8 cooling/heating cycles. This work reports a composite film using (3-Aminopropyl)triethoxysilane-modified boron nitride nanosheets (BNNS) incorporated in the aramid nanofibers (ANF) network via sol–gel method. High-resolution TEM, SEM, XPS, and XRD outcomes confirmed the imitation pearl layered structure—BNNSs as thermal conductive fillers were layer-by-layer overlapped on ANF. The reasonable coordination between interfaces and fillers stimulated the thermal conductivity (35.4 W (m·k)-1) of composite film i.e., 338.43 % higher than that of ANF. The composite film exhibited good cyclic thermal stability, high tensile strength (65.9 MPa), and high volume resistivity (2.424 × 1015 Ω∙cm). [ABSTRACT FROM AUTHOR]

The present study investigates the application of annealing and plasma-activated water (PAW) for starch modification, as alternative methods compared to the chemical one. Native potato starch was subjected to PAW, annealing with distilled water (DW-ANN), and the combination of the two (PAW-ANN) at different incubation times (1, 4, 8, and 12 h). The changes in rheological, pasting, and thermal properties were evaluated. The results showed that all treatments promoted significant modifications of the investigated parameters. In particular, while the pasting properties of the potato starch remained unchanged after the PAW treatment, G' (elastic) and G" (viscous) of the PAW-treated starch were significantly (p < 0.05) higher than those of the native. DW-ANN significantly increased all rheological parameters and reduced peak viscosity, breakdown, and setback and significantly (p < 0.05) incremented pasting temperature, holding strength, and final viscosities of the potato starch may be due to cross-linking reaction. The combination of treatment (PAW-ANN) showed a synergistic effect leading to strong gel formation up to 4 h, while further treatment reduced the possibility of depolymerization. In conclusion, the combined treatment is a promising new green method to modify the properties of starch and improve its stability within a short treatment time. • Plasma-activated water and annealing were combined for potato starch modification. • Effect of incubation time was investigated for the first time. • All treatments increased the starch viscosity. • The thermal stability and the stability against retrogradation were increased. • The treatments showed a synergistic effect, allowing to reduce total processing time. [ABSTRACT FROM AUTHOR]

The thermal properties of AlCrN coatings influence their application in harsh mechanical environments. This paper introduces a Si-Nb co-alloying strategy to prepare AlCrN-based coatings with good mechanical properties, excellent thermal stability and resistance to high temperature oxidation for developing high-performance tool coatings. The results indicate that, benefiting from the synergistic effect of replacing a portion of Si with an appropriate amount of Nb, Al 0.59 Cr 0.31 Si 0.06 Nb 0.04 N coating exhibits a fine columnar crystal structure different from the featureless dense structure of Al 0.60 Cr 0.32 Si 0.08 N coating. The different microstructure results in the difference of mechanical properties. Therefore, Al 0.59 Cr 0.31 Si 0.06 Nb 0.04 N has a higher hardness (32.3 ± 0.8 GPa) than Al 0.60 Cr 0.32 Si 0.08 N (28.8 ± 0.8 GPa). Meanwhile, the Al 0.59 Cr 0.31 Si 0.06 Nb 0.04 N coating get a better thermal stability and a comparable resistance to high temperature oxidation as Al 0.6 Cr 0.32 Si 0.08 N coating. The temperatures of thermal decomposition and oxidation resistance for Al 0.59 Cr 0.31 Si 0.06 Nb 0.04 N coating are increased by about 125 °C and 175 °C, respectively, compared with Al 0.66 Cr 0.34 N coating. In addition, the Si-Nb co-alloyed coatings maintain a better hardness after annealing. • Si-Nb co-alloying can improve the mechanical and thermal properties of AlCrN-based coatings. • Al 0.59 Cr 0.31 Si 0.06 Nb 0.04 N coating shows better hardness than Al 0.6 Cr 0.32 Si 0.08 N coating. • Nb addition retains the excellent thermal properties of Al 0.6 Cr 0.32 Si 0.08 N coating. • The thermal decomposition onset temperature of Al 0.59 Cr 0.31 Si 0.06 Nb 0.04 N coating is ~1075 °C. • The oxidation resistance onset temperature of Al 0.59 Cr 0.31 Si 0.06 Nb 0.04 N coating is ~1275 °C. [ABSTRACT FROM AUTHOR]

Tribological and thermophysical characteristics of a new hybrid nanolubricant that incorporates melamine functionalized graphene oxide (mGO) and imidazolium cation based ionic liquid (IL) in a polyalphaolefin (PAO-6) base oil have been investigated. Different formulations of nanolubricants with 0.05 wt%, 0.1 wt% nanosheets and 1 wt% ionic liquid were studied to examine the synergistic effects of surface functionalization and ionic liquid addition on the antifriction and antiwear properties of the PAO-6 base oil. Thermal stability studies involved Thermogravimetric analysis to analyze the oxidation onset and decomposition temperature of different formulatons at varying weight concentrations of nanoadditives. Anti-friction performance was quantified by the coefficient of friction (COF) reduction compared to neat lubricant. The highest reduction in COF was observed for 0.05 wt% mGO + 1 wt% IL with an outstanding 73.33% reduction followed by 0.05 wt% mGO and 0.05 wt% GO with 73% and 67% reduction respectively. Post-wear analysis of the wear scars was performed using 3D optical profiler, SEM micrographs, EDX elemental composition and Raman spectra. The highest reduction in wear depth was observed in the case of PAO-6 + 0.05% mGO with a value of 46.3% followed by a 39.9% reduction in the case of PAO-6 + 0.05% GO. The morphologies of samples containing both ionic liquid and nanosheets exhibited a much smoother surface with the absence of deep grooves and pits which was attributed to the formation of a strongly bonded tribofilm owing to the chemical interactions between ionic liquid capped nanosheets and metal substrate. Strong interfacial interactions also induced a significant increase in the thermal stability of the nanofluids. The maximum shift observed in the oxidation onset temperature compared to neat PAO-6 was 68◦C while the decomposition temperature increased by 61◦C. Due to their excellent friction, wear, and thermal properties, these hybrid nanofluids could be applied in various highly demanding industrial sectors such as automotive, machining operations, aerospace, thermal power plants and micro/nano-electromechanical systems. [Display omitted] • Hybrid nanolubricant incorporating melamine functionalized graphene oxide (mGO) and [EMIM][Tf2N] ionic liquid (IL) in polyalphaolefin (PAO-6) has been formulated. • 0.05 wt% mGO + 1 wt% IL formulation exhibited an outstanding 73.33% reduction in the coefficient of friction compared to neat PAO. • A maximum reduction of 46.3% in wear track depth (WTD) and 44.5% in wear track width (WTW) has been achieved. • The oxidation onset temperature increased by 68◦C while the decomposition temperature increased by 61◦C for PAO + 0.05% m-GO+ 1% IL formulation. • [EMIM][Tf2N] played a significant role in the formation of a robust, chemically bonded tribofilm as evidenced by the Raman and EDX data. [ABSTRACT FROM AUTHOR]

Mechanical recycling is a viable option for reducing plastic waste, especially for post-consumer waste and scraps from production processes. Biodegradable polymers have gained attention as alternatives to conventional ones, and their potential for reprocessing using standard techniques before composting needs to be explored. This study focused on a commercial biodegradable polymer blend which underwent ten extrusion cycles to assess the effects of mechanical recycling on mechanical properties, rheological behavior, and thermal stability. The results indicated that the blend's mechanical properties were largely maintained across the extrusion cycles, with only a 53 % decrease in ductility. The thermal stability slightly declined by 2.3 % in T 5% onset temperature. This can be attributed to a balance between molecular chain scission (resulting in an average molecular weight reduction of approximately 8.4 %) and crosslinking phenomenon (evidenced by an increase in complex viscosity throughout the extrusion cycles). Overall, the results suggest a suitable recycling attitude of this material. • The impact of mechanical recycling on a commercial polymer blend was studied. • The mechanical recycling was simulated using repeated extrusion/injection molding. • The mechanical, rheological and thermal properties of the blend were assessed. • The reprocessing had negligible effects on the thermal stability of the blend. • The crosslinking contributed in preserving good mechanical properties. [ABSTRACT FROM AUTHOR]

Over the past decade, the study of nanostructured high-entropy alloys (HEAs) has attracted great attention due to their high strength (grain boundary hardening) and improved thermal stability over conventional nanostructured metals and alloys. However, a lingering issue yet to be resolved by these studies is that of commercial viability; the synthesis processes used to date are costly, not easily scalable, and energy intensive. This work examines the thermal stability and mechanical properties of electrodeposited nanostructured HEAs, towards establishing a cost-effective and versatile synthesis route to commercialize this underutilized material class. Nanocrystalline, amorphous, and nanoglass alloys of NiFeCoW, NiFeCoMo, and NiFeCoMoW were systematically characterized to assess the stability of their structure and mechanical properties, compared against conventional nanocrystalline materials and HEA counterparts. The structural stability of these electrodeposited HEAs was shown to improve with increasing number of elements, from a peak temperature for grain growth of ∼270 °C in pure nanocrystalline Ni, to ∼500 °C in electrodeposited HEAs, corresponding to a near doubling of the activation energy for grain growth from 1.3 eV (Ni) to a maximum of 3.1 eV (NiFeCoW). This improved stability was matched with a 60 % increase in hardness after annealing to the point of nanograin nucleation (∼500 °C), to a maximum hardness of ∼8.4 GPa. Such hardening trends followed an extrinsic inverse-to-regular Hall-Petch relationship, where the inverse regime was largely dominated by grain boundary relaxation and nanoglass structural breakdown. With these results, we have established electrodeposition as a promising candidate route for fabricating nanostructured HEAs for applications at elevated temperatures. [Display omitted] • First comprehensive investigation of mechanical properties and thermal stability of electrodeposited nanostructured high-entropy alloys. • The family of NiFeCoMoW alloys is structurally stable up to ∼500 °C. • Annealing brings out an extrinsic inverse-to-regular Hall-Petch hardening transition. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) are grown uniformly on the surface of white porous boron nitride nanofibers (BNNFs) via a thermal reduction method to overcome the issue of nanoparticle aggregation. The optical characteristics of the AgNPs are retained, with different colors present depending on reduction temperature. This mainly depends on the white appearance of BNNFs. In addition, compared to boron nitride (BN) nanosheets and nanospheres, abundant pore structure and high specific surface area of the BNNFs enable superior AgNPs loading without agglomeration. The prepared AgNPs-loaded BNNFs (Ag-BNNFs) are then incorporated into poly (vinyl alcohol) (PVA) hydrogels fabricated through cyclic freeze-thaw techniques to develop antibacterial Ag-BNNFs/PVA composite hydrogels. The addition of 3 wt% Ag-BNNFs increases the tensile strength by 73.1% and compressive strength by 92.8% relative to the unmodified PVA hydrogels. Thermal stability also improves considerably, with the maximum PVA decomposition rate shifting from 280.9°C to 323.6°C in the composite hydrogels. Importantly, a potent bactericidal effect against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) are achieved, with 99.5% and 100% inhibition after 24 h exposure to the Ag-BNNFs/PVA composite hydrogels, respectively. This work demonstrates a new method of dispersing AgNPs with BNNFs, and the resulting Ag-BNNFs effectively enhance the mechanical properties, thermal stability and antibacterial activity of PVA hydrogels. [Display omitted] [ABSTRACT FROM AUTHOR]

Polyimide (PI) has been extensively used in 5G microelectronics however the relatively high dielectric constant (∼3.5) and moisture adsorption have greatly limit its practical applications in high-frequency region. Here hydrophobic PI/SiO 2 composite films with low dielectric constant and excellent thermal stability were synthesized by dispersing methyl modified hollow silica nanospheres (MHS) into polyamic acid solution prior to imidization treatment. Comparing with unmodified hollow silica nanospheres (HS), the MHS obtained through methyl modification can disperse uniformly in the PI matrix. Thus, the relaxation and orientation polarization of the PI chains as well as their electron migration are suppressed, resulting in a significant decrease in dielectric constant. The PI/MHS-10% film exhibits a stable low dielectric constant (1.9–2.3) in the high-frequency range (8.2 GHz–12.4 GHz), meanwhile maintains a high breakdown voltage (192 kV/mm), mechanical properties (64 MPa) and an excellent thermal stability (T d5% = 546.5 °C; T max = 589.0 °C). Moreover. PI/MHS demonstrates much lower linear expansion coefficient of 25.0 ppm/K that better matches the substrate. The surface contact angle of PI/MHS increases from 73° to 110° and the water absorption rate decreases from 3.1% to 1.6%, effectively avoiding the moisture adsorption. This work provides a simple method to prepare high-performance composite films for 5G practical applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Effects of agar on the rheological property and heat stability of casein micelle gels induced by rennet were investigated. The interactions between casein micelle and agar were investigated. Electrostatic interactions between casein micelle and agar were not observed. The movement of agar characteristic bonds indicated the hydrogen bond interaction existed in the casein micelle/agar mixture. The addition of agar promoted the casein micelles aggregation and decreased the rennet coagulation time (RCT) and the storage modulus (G'). The strip-like network microstructure changed into a sheet-like network after the addition of agar. The composite gels were present as a bicontinuous phase structure. The agar and protein were both present as continuous phases. The addition of 0.5% agar increased the water holding capacity (WHC) from 63.30% to 92.44% and decreased the gel hardness from 73.41 g to 60.57 g. The protein digestion rate of gels increased after agar addition during gastric digestion. The WHC increased from 35.20% to 83.56% and the microstructure of gels improved by the addition of 0.5% agar after heating at 80 °C for 30 min. In conclusion, the WHC and thermal stability of the gels improved after the addition of agar. [Display omitted] ● The hydrogen bond interaction existed in the casein micelle/agar mixture. ● The addition of agar decreased the rennet coagulation time and the storage modulus. ● The composite gels had a bicontinuous phase structure. ● The addition of agar improved the thermal stability of the gels. [ABSTRACT FROM AUTHOR]

Crowded environments, commonly found in the food system, are utilized to enhance the properties of soybean proteins. Despite their widespread application, little information exists regarding the impact of crowded environments on the denaturation behaviors of soybean proteins. In this study, we investigated how crowding agents with varying molecular weights, functional groups, and topology affect the denaturation behavior of glycinin under crowded conditions. The results reveal that thermal stability in PEG crowded environments is mainly influenced by both preferential hydration and binding. The stabilization is primarily enthalpy-driven, with aggregation contributing additional entropic stabilization. Specifically, ethylene glycol and diethylene glycol exhibit temperature-dependent, bilateral effects on glycinin stability. At the denaturation temperature, hydrophobic interactions play a predominant role, decreasing glycinin's thermal stability. However, at a molecular weight of 200 g/mol, there is a delicate balance between destabilizing and stabilizing effects, leading to no significant change in thermal stability. With the addition of PEG 400, 1000, and 2000, besides preferential hydration, additional hard-core repulsions between glycinin molecules enhance thermal stability. Methylation modification experiments demonstrated that 2-methoxyethyl ether exerted a more pronounced denaturing effect. Additionally, the cyclization of PEG 1000 decreased its stabilizing effect. [ABSTRACT FROM AUTHOR]

[Display omitted] • Slow evaporation synthesis method at room temperature of (C 6 H 7 N 2 S)NO 3. • Hybrid nitrate salt of 4-pyridinethioamide with a supramolecular crystal structure. • A good thermal stability for a wide range of temperatures. Organic-inorganic hybrid nitrate salt associating the aromatic organic molecule 4-pyridinethioamide with the (C 6 H 7 N 2 S)NO 3 formula was synthesized by slow evaporation method at room temperature. The obtained material is crystallized in the monoclinic system with the centro-symmetric space group P 2 1 / c. The supramolecular crystal structure was built from nitrate anions N O 3 - entities linked to the organic cations (C 6 H 7 N 2 S)+ by hydrogen bonds and weak interactions. Besides, the aromatic pyridinium rings of 4-pyridinethioamide molecules were proven to form chains through π...π interactions. The Hirshfeld analysis results have shown that in all potential molecular contacts, the H...O/O...H constitutes the most important interaction in the crystal with a contribution percentage of 39 %. The thermal behavior studied by thermogravimetric analyses revealed good stability up to 175 °C. Preliminary analyses recorded with infrared and Raman spectroscopy confirmed the existence of vibrational modes corresponding to the formation of the hybrid compound before performing the characterization by X-ray single-crystal diffraction. The optical absorption spectrum exhibits two bands located at 4.82 eV (257 nm) and 3.95 eV (314 nm), which can be even observed with the naked eye at room temperature and is due to exaction emission. [ABSTRACT FROM AUTHOR]

It work provides a simple and effective doping strategy to obtain high-temperature cycle service stability of Cu 2 Se-based thermoelectric materials while maintaining their intrinsic excellent thermoelectric properties. Cu 2-x Cd x Se (x = 0, 0.02, 0.04, and 0.06) block materials were synthesized by vacuum melting annealing and spark plasma sintering (SPS). The effects of Cd doping on the composition, microstructure, band structure, and thermoelectric properties of Cu 2 Se were investigated. The development of Cd doping on the thermoelectric stability of Cu 2 Se was studied by four high-temperature cycles. The results show that Cd doping can reduce Cu + migration and improve its thermoelectric stability. The dissolution of Cd in Cu 2 Se is limited, and a second phase of CdSe is found in samples with high Cd content (x = 0.04 and 0.06). The second phase CdSe and element segregation (copper-rich phase) in the x = 0.06 sample enhance phonon scattering and reduce lattice thermal conductivity (κ l). Therefore, the maximum ZT value of the Cu 1 · 94 Cd 0 · 06 Se sample at 873 K (about 1.37) is about 1.02 times higher than that of the undoped sample (about 1.34). The research will accelerate the practical application of liquid thermoelectric materials and provide the possibility of Cu 2 Se series thermoelectric materials in the use of waste heat power generation in the middle-temperature area, which has great application prospects. • There is a second CdSe phase and the segregation of elements (copper-rich phase), enhancing the phonon scattering and reducing κ l. • The Cu 1 · 94 Cd 0 · 06 Se sample is about 1.02 times higher at 873 K (about 1.37) than that of the undoped sample (about 1.34). • The Cd impurity sample and pure phase Cu 2 Se have the exact the scattering characteristic of ionized impurities. • The high-temperature cycle stability is better than that of Cu 2 Se. [ABSTRACT FROM AUTHOR]

Cu 1.8 S has received a lot of interest as a prospective thermoelectric material with the best performance and abundant resources. While high charge carrier concentration contributes to the high electrical conductivity and power factor values, grain-boundary engineering is required to improve the phonon scattering and thermal stability of Cu 1.8 S. We used a simple process that combined nanoparticles via mechanical alloying and post-annealing to introduce the reduced graphene oxide (rGO) heterointerface into the Cu 1.8 S matrix. A significant enhancement of power factor has been realized that the highest power factor is 721 μWm−1 K−2 at 550 K in the composite Cu 1.8 S/rGO with 10 % rGO, which is higher than the pure Cu 1.8 S. Furthermore, following four cycles of testing from ambient temperature to 550 K, the composite demonstrated excellent repeatability of power factor, confirming its practical application potential. [Display omitted] [ABSTRACT FROM AUTHOR]

Hydrophobic surfaces and super hydrophobic surfaces have been widely studied and applied to cotton, ceramics, glass and other surfaces, but less research has been done on environmentally responsive hydrophobic surfaces (ERHS). In this paper, the environmentally responsive low fluorine epoxy copolymer P(DMAEMA- r -TFEMA- r -GMA) was synthesized by traditional free radical polymerization and the obtained copolymer was applied to construct ERHS on the cotton fabric and wood/plastic composite (WPC). The effects of construction parameters (polymer concentration, pH value of impregnation solution, impregnation temperature, impregnation time, drying temperature and drying time) on the surface hydrophobic properties of cotton fabric and WPC were studied. L 25 (56) orthogonal experiment scheme was selected to explore the optimal parameters of hydrophobic construction. The optimum construction conditions of ERHS cotton and ERHS WPC were as follows: polymer concentration of 10 mg/mL, impregnation time of 9 h, pH of 9, impregnation temperature of 50 °C and 60 °C, drying time of 6 h, and drying temperature of 120 °C. The maximum water contact angle (WCA) on the surface of ERHS cotton was 145°. After 15 times pH-stimulation circulations, the WCA changed in the range of 145° ± 5° to 120° ± 5°. After 10 times acid-base response circulations, ERHS cotton had good oil-water separation capacity, and the maximum oil-water separation rate varied from 99.82% to 98.24%. This hydrophobic modification had no effect on the thermal stability of cotton fabric. The maximum WCA of ERHS WPC was 135°. Under acidic conditions (pH=2), the water absorption rate of wood plastic was improved. The hydrophobic modification had little effect on the mechanical properties and thermal stability of WPC. [Display omitted] • The pH responsive copolymer P(DMAEMA- r -TFEMA- r -GMA) was applied to construct environmentally responsive hydrophobic surfaces. • In order to explore the optimal parameters of hydrophobic construction, L 25 (56) orthogonal experiment scheme was selected. • The hydrophobic modification had little effect on the mechanical properties and thermal stability of WPC. [ABSTRACT FROM AUTHOR]

Thermal stability and physicochemical properties as a function of heating temperature, pH and salt addition was compared between caprine and bovine milk protein concentrate dispersions. Caprine milk protein concentrate (MPC) had a lower amount of heat coagulation time and a higher percentage of sediments than bovine MPC. Calcium ion activity of caprine MPC was higher than that of bovine. The amount of κ-casein in the serum of caprine MPC dispersions was higher than that of bovine, and increased with increasing temperatures, pH and the addition of NaCl and citrate. The amount of whey protein in serum was also higher in heated caprine MPC compared with bovine. Particle size of caprine MPC was larger than bovine MPC and was more susceptible to induced aggregation. The lower thermal stability of caprine MPC might be associated with the higher calcium ion activity and the higher amount of κ-casein dissociation promoted by whey protein denaturation and complexation in serum. [ABSTRACT FROM AUTHOR]

This study aimed to improve the functional properties of egg white protein (EWP) by covalent modification of EWP with xanthan gum (XG) and gallic acid (GA)/tannic acid (TA) to form covalent complexes. The structure and functional properties of EWP before and after modification were explored. The results showed that the grafting degree of EWP-GA-XG and EWP-TA-XG reached 37.23% and 44.01% respectively measured by the OPA method. The secondary structure of EWP became loose after reaction with GA/TA and XG, with a decrease in the content of α-helix and an increase in the β-sheet content, thus contributing to the improvement of its functional properties. The DPPH and ABTS radical scavenging rate and iron reduction ability of EWP-GA-XG (44.94%, 56.38%, 18.29 mg VC/μmol) and EWP-TA-XG (85.45%, 88.39%, 39.26 mg VC/μmol) complexes were significantly improved compared with EWP (7.90%, 12.94%, 0.12 mg VC/μmol). The emulsion activity index and emulsion stability index of EWP-GA-XG (10.05 m2/g, 96.43%) and EWP-TA-XG (11.04 m2/g, 96.53%) complexes were also improved as compared to those of EWP (5.94 m2/g, 51.45%). Moreover, the peak transition temperatures of EWP-GA-XG (138.09 °C) and EWP-TA-XG (143.96 °C) complexes were higher than that of EWP (125.00 °C). This study may provide the theoretical basis for improving the functional properties of EWP and expanding its application in the field of food. [Display omitted] • The complexes of EWP-GA/TA-XG were prepared by alkali method and Maillard reaction. • The covalent binding of EWP with GA/TA and XG resulted in a looser structure of EWP. • The complexes EWP-GA/TA-XG significantly enhanced the antioxidant activity of EWP. • The complexes EWP-GA/TA-XG improved the emulsifying property and stability. [ABSTRACT FROM AUTHOR]

Micro-to-nano transformation can make a material unique. This research uses jute microfiber to extract Holo and Alpha forms of cellulose, which are later attempted to electrospun into superfine nanofibers (NFs). Initial investigation of morphological, physicochemical, crystallographic, and thermal properties confirmed successful synthesis of Holo and Alpha-cellulose (H/A-cellulose). Afterwards, the electrospinnable concentration of H/A-cellulose was optimized and their bead-free ultrafine NFs in the range of 109–145 nm were fabricated. FTIR analysis confirmed the source composition in Holo and Alpha CNF with the partial formation of trifluoroacetyl esters. Alpha CNF exhibited better structural integrity despite the crystallinity and thermal stability deteriorated in both Holo and Alpha CNF. Both Holo and Alpha CNF exhibited adequate mechanical performance and liquid uptake properties. Alpha CNF showed better morphological stability in organic solvents and slower biodegradation than Holo CNF. Subsequent investigation revealed that both Holo and Alpha CNF didn't exhibit cytotoxic effects on COS-7 cells and above 90 % of cells were viable in contact with both CNF. Significant proliferation and attachment of COS-7 cells were noticed within 7 days of incubation with the prepared CNF. Our findings revealed that jute-extracted cellulose can be a viable and potential source for constructing cellulose-based advanced nano-biomaterials. Graphical representation of the scaffold fabrication. [Display omitted] • Extraction of Holo and Alpha-cellulose from jute fiber • Fabrication of Holo and Alpha CNF via electrospinning • Alpha CNF was more structurally stable than Holo CNF. • Holo CNF and Alpha CNF have adequate surface-wetting and liquid uptake properties. • Both Holo CNF and Alpha CNF were non-toxic against COS-7 cells and favored excellent cell proliferation and attachment. [ABSTRACT FROM AUTHOR]

• Strict controlled segment length and alternate sequence. • P(AMMO-ab-EG) exhibit excellent flexibility and thermal properties. • Fine controlled segment lengths enable high crystallinity but lower T g value. The flexibility of high energy polymers is hindered by bulky and polar high energy groups, resulting in reduced mechanical properties. In this paper, poly(3-azidomethyl-3-methyloxetane-glycol) (P(AMMO-ab-EG)) with an alternating block structure was synthesized and characterized. Diethylene glycol and triethylene glycol are used to improve flexibility, which length in this polymer structure is tightly controlled. (P(AMMO-ab-EG)) exhibits good flexibility, suitable viscosity and good thermal stability. It was found that P(AMMO-ab-DEG) exhibited a lower glass transition temperature but higher viscosity and better temperature viscosity sensitivity than P(AMMO-ab-TEG). These results demonstrate that fine tuning of the block length has a greater effect on T g than on viscosity. This finding is of great significance to prepare energetic polymers with good processing properties and lower T g value. Al, the prepared (P(AMMO-ab-EG) has excellent compatibility with NG (nitroglycerine) and NP (bis(2,2-dinitropropyl)acetal and bis(2,2- dinitropropyl)formal). [Display omitted] [ABSTRACT FROM AUTHOR]

Enhancing the mechanical properties and thermal stability of phthalonitrile polymers by hybrid modification holds significant importance in broadening their thermal-structural applications within high-temperature environments. Herein, fumed silica nanoparticles were considered as modifiers for a class of phenolic-type phthalonitrile resin, i.e., PN75, and their effects on mechanical properties and thermal stability were explored. First, contact angle tests (CA) were employed to show that the PN75 melt had good wettability on hydrophilic fumed silica (FS) and poor wettability on hydrophobic fumed silica (RFS). FS had a relatively satisfactory dispersion within PN75, which was indicated by scanning electron microscope (SEM), followed by FS/PN75 nanocomposites were prepared by melt blending under vacuum, with maximum FS addition 3 wt% of PN75. Second, the flexural strength and modulus of nanocomposites were increased by 23.5% and 11.9%. Finally, thermal stability of the FS/PN75 was promoted from 21.6% to 25.6% in char residue at 800 °C in the air atmosphere by the thermogravimetric analysis (TGA), which was contributed by the high heat-resistance and the shielding effect of FS. This work would inspire in-depth studies on modification and design of phthalonitrile-based hybrid composites for extreme thermal environment. [Display omitted] • Hydrophilic fumed silica exhibited well wettability with phenolic-type phthalonitrile resin. • Vacuum melt blending was proven as an efficient process achieving well dispersion of fumed silica nanoparticles. • Addition of fumed silica into phthalonitrile polymers improved the flexural strength and the char residue. [ABSTRACT FROM AUTHOR]

Having poor interfacial compatibility between biochar microsphere (BM) and polylactic acid (PLA) should be responsible for the unbalance of composite film strength and toughness. Elucidating the effect of polydopamine (PDA) on BM and BM/PLA composite films is the ultimate goal of this study based on the mussel bionic principle. It was found that the strong adhesion of PDA on the BM surface was achieved, which improved the surface roughness and thermal stability. Also, PDA modification can facilitate crystallization, increase thermal properties, improve interfacial compatibility, and enhance the tensile properties of BM/PLA composite films. Silane-based PDA modified BM/PLA composite film exhibited the best tensile strength, tensile modulus, and elongation at break with 77.95 MPa, 1.87 GPa, and 7.30%. These noteworthy findings, achieving a simultaneous improvement in PLA strength and toughness, hold promising implications for its sustainability. [Display omitted] [ABSTRACT FROM AUTHOR]

Concerns over the escalating energy crisis have prompted extensive study and application of energy storage technology as a means to augment energy efficiency. Molten salts (MSs) feature prominently as phase change material (PCM) due to their considerable latent heat, broad operating temperature range, high heat storage density, and cost-effectiveness. This paper presents a survey of the advancements in the study of preparation methods, heat transport characteristics, phase change characteristics, and thermal stability of MSs over the past three years. Heat transport characteristics encompass thermal conductivity, specific heat capacity, thermal diffusivity, and viscosity. Phase change characteristics include melting point, latent heat, subcooling, nucleation methodology, and heat storage density. The review also explores the promising domain of nano-enhancement technologies and the analysis of MSs' thermal conductivity via phonons. [Display omitted] • Recent progress in properties modifications of molten salts is reviewed. • Adding skeleton materials affects the thermal storage performance. • Nanoparticles are the properties enhancer of molten salts. • Preparation techniques of molten salts impacts the thermal storage performance. • Waste treatment is applied in thermal energy storage of MSs. [ABSTRACT FROM AUTHOR]

• CNC with similar molecular structure and composition to NC can be used in propellant. • Civilian nitrocellulose can further plasticize high-nitrogen nitrocellulose. • The thermal stability of CNC based-propellant was enhanced and presented stable combustion behavior. Developing binders for propellants with balanced mechanical and energy properties is important and challenging. Herein, high-viscosity civilian nitrocotton (CNC) was used as reinforcing binder to prepare CNC-based propellant by solvent method. The influence of viscosity and content of CNC on mechanical properties, thermal stability, and combustion performance of propellants was investigated. The plasticizing process of nitrocellulose fibers can be well described by swelling mass changes and has a strong correlation with mechanical properties. The impact test combined with morphology observation by scanning electron microscope (SEM) and evaluation about matrix, fiber, and structure systems revealed that the subsidiary plasticizing mechanism of CNC and the homogeneous system of CNC-based propellant play the dominant role in enhancement of macroscopic mechanical properties. Besides, the structure of propellant was investigated using FTIR, XRD, and Raman, which indicated that propellant containing CNC exerting similar structure with NC-based propellant. Moreover, the analysis of thermal decomposition kinetics demonstrated that the introduction of CNC could further enhance the thermal stability of propellant, like the increased activation energy. Finally, the study of combustion performance demonstrated that CNC-based propellant can burn steadily, and energy out-put was further enhanced as compared with NC propellant. Therefore, this design and adjustment for the introduction of CNC in propellant could provide fundamental theory and data support for the development of CNC in propellants. [ABSTRACT FROM AUTHOR]

In this study, an efficient polyfluoride red-emitting phosphor, Cs 3 RbGe 2 F 12 :Mn4+ (denoted as CRGF:Mn), has been synthesized using a simple co-precipitation method. The crystal and electronic structures, spectroscopic properties, and photoluminescence thermal stability of CRGF:Mn have been systematically characterized. The results show that Mn4+ ions experience a strong crystal field and present a series of intense red emission peaks under blue light excitation. Moreover, CRGF:Mn exhibits a high color purity (95.1 %), high internal quantum efficiency (82.4 %), and enhanced photoluminescence thermal stability at 150 °C, with an intensity of 113 % relative to room temperature. A warm white light-emitting diode exhibiting a low correlated color temperature (3572 K), high color rendering index (90.7), and suitable luminous efficiency (132.6 lm/W) was prepared using CRGF:Mn as a red component, demonstrating viable application in solid-state lighting. • Synthesis of CRGF:Mn polyfluoride red phosphor with a high internal quantum efficiency (82.4 %). • CRGF:Mn exhibits outstanding photoluminescence thermal stability (113 % at 150 °C). • The application prospect of CRGF:Mn for indoor lighting have been elaborated. [ABSTRACT FROM AUTHOR]

Dy3+/Sm3+ double-doped, Tb3+/Sm3+ double-doped and Dy3+/Tb3+/Sm3+ triple-doped GeO 2 -B 2 O 3 –Na 2 O–SrO-Ga 2 O 3 (GBNSG) luminescent glass was prepared by high temperature melting method, and its structure, energy transfer mode, luminescence properties and thermal stability were studied. The results show that Dy3+/Sm3+ double-doped GBNSG luminescent glass transfers energy from Dy3+ to Sm3+ in an electric dipole-electric dipole manner, with an energy transfer efficiency of 87.56%. Tb3+/Sm3+ double-doped GBNSG luminescent glass in which Tb3+ transfers energy to Sm3+ in an electric-dipole-electric-dipole fashion, with an energy transfer efficiency of 92.24%. The decreasing fluorescence decay lifetime of Dy3+ in Dy3+/Tb3+/Sm3+ triple-doped GBNSG luminescent glass indicates that Dy3+ transfers energy to Tb3+ and Sm3+. The CIE chromaticity coordinates of GBNSG-0.5Dy3+/0.8 Tb3+/1.0Sm3+ luminous glass are (0.3387, 0.3374), and the correlation color temperature is 5228 K, which realizes the white light emission. The ΔE of GBNG-0.5Dy3+/0.8 Tb3+/1.0Sm3+ luminous glass is up to 0.246 eV, indicating that it has good thermal stability. • GeO 2 -B 2 O 3 –NaO–SrO-Ga 2 O 3 (GBNSG) glass matrix, which has not been reported before, was prepared by high temperature melting method. • Under 365 nm excitation, the CCT value of the GBNSG-0.5Dy3+/1.0Sm3+ luminescent glass is 5812K, and the CIE chromaticity coordinates are (0.3258, 0.3364), close to standard white light. • Under 365 nm excitation, the CCT value of the GBNSG-0.5Dy3+/0.8Tb3+/1.0Sm3+ luminescent glass is 5228K, and the CIE chromaticity coordinates are (0.3387, 0.3374), achieving white light emission. [ABSTRACT FROM AUTHOR]