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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]

In this work, Ge 8 Sb 2 Te 11 (GST) films with high melting point element Mo doping were prepared by magnetron co-sputtering, and the influence of Mo content on the phase transformation and optical properties of the films was investigated. The results of GIXRD, XPS, and ellipsometry analysis show that Mo will occupy the lattice vacancy, promoting grain growth and accelerating phase transitions. With an increase in Mo content, the phase transition temperature of the films can reach 360 °C, and the amorphous thermal stability of the films can be enhanced by Mo doping. Meanwhile, the optical properties of the films are improved. The optical band gap of Mo-doped films is reduced, the absorption coefficient rises, and the refractive index contrast of GST films with low Mo-doping in the Vis-NIR band is as high as 2.27. This result will make it possible to apply Ge 8 Sb 2 Te 11 thin films in structural color fields and broaden their color spectrum. [ABSTRACT FROM AUTHOR]

Lead-free piezoceramics with superior piezoelectric properties don't meet the requirements of practical applications due to their lower phase transition temperature and poor thermal stability. In the present work, we report a new insight into the effect of glass phase on the piezoelectric, Curie temperature and thermal stability of (Ba 0.85 Ca 0.15)(Ti 0.9 Zr 0.1)O 3 (BCZT) ceramic. Unlike traditional glass materials with more than 80% of B 2 O 3 and SiO 2 as glass formers, our approach is to fabricate a glass phase (Ba 0.85 Ca 0.15)(Ti 0.9 Zr 0.1)O 3 -0.05B 2 O 3 (abbreviate BBCZT) with the same elements and concentrations as the ceramic phase. The ceramics-doped glass samples with the composition [(1-x)BCZT-xBBCZT], where x=(0.0, 0.025, 0.05, 0.075 and 0.1 wt%), were sintered according to the glass phase content. The effect of BBCZT glass composition on the crystal structure, dielectric, ferroelectric and piezoelectric properties of BCZT was investigated in detail. X-ray diffraction revealed that the addition of glass phase causes a defect engineering of the tricritical triple point of BCZT ceramic, where the tetragonal (T) and rhombohedral (R) phases were suppressed by the addition of glass phase and the T-phase has completely vanished at x = 0.05. The maximum value of permittivity (ε = 4102) and converse piezoelectric coefficient (d* 33 = 1150 Pm/V) were achieved for the 0.975BCZT-0.025BBCZT sample at ambient temperature. Furthermore, the diffusion coefficient (γ) and Curie temperature (T c) were observed to increase beyond x = 0.025, indicating enhanced thermal stability of BCZT at high glass content. These results qualify that the addition of (BBCZT) can enhance piezoelectric properties, phase transition temperature and thermal stability of BCZT ceramic which can meet wide requirements of practical applications. [ABSTRACT FROM AUTHOR]

ZIF-L, a metal-organic framework (MOF) material, has a two-dimensional (2D) foliation, a large specific surface area, excellent thermal stability and CO 2 adsorption performance, respectively. In this work, in order to further improve the thermal insulation performance of SiO 2 aerogel composite fabrics, ZIF-L powder was first prepared as a reinforcing particle, and then added to silica aerogel. Finally, SiO 2 /AF/ZIF-L composites were obtained by solution impregnation method. The influence of different ZIF-L concentrations on the insulation performance of composites and their influencing factors were studied. Furthermore, these composites were fully characterized using BET measurement, Instron 5967, precision transient thermal performance tester, infrared thermal imager, insulation performance test, thermogravimetric analyzer, and dynamic thermomechanical analyzer. The results showed that 0.12% SiO 2 /AF/ZIF-L composites had excellent thermal insulation performance, with a thermal conductivity as low as 0.029 W/(m·K). In addition, SiO 2 /AF/ZIF-L composites fabricated by atmospheric drying method had the best thermal insulation performance under the conditions of gel time of 24 h, hydrolysis time of 5 h, and polycondensation pH value of 5–6. [ABSTRACT FROM AUTHOR]

Layered materials exhibit competitively low thermal conductivity along the out-of-plane direction. The solution process is a promising method for preparing stacked structures. However, the thermal stability of the layered materials is poor after processing in solution, thus hindering their applications at high temperatures. One of the solutions to improve the thermal stability of layered structures is to expand the interlayer distance by inserting large-size metal ions. In this work, we studied the thermal properties of Cs+ intercalated layered niobate obtained by the ion-exchanged process. The layered structure of the Cs+ intercalated layered niobate survives after thermal treatment even at 1200 °C. The room temperature thermal conductivity of as prepared stacked Cs–HCa 2 Nb 3 O 10 is as low as 0.11 W m−1 k−1. Upon thermal annealing, the thermal conductivity increases. After annealing at 1200 °C, the value is 0.90 W m−1 k−1. The finding suggests Cs+ intercalated layered niobate is a promising material for high-temperature insulation applications. [ABSTRACT FROM AUTHOR]

Herein, Nd 2 O 3 -doped 0.11PIN-0.89PHT (PIN-PHT) single-phase tetragonal piezoelectric ceramics are prepared by traditional solid-phase method. In addition, impacts of Nd-doping on crystal structure and electrical performance for 0.11PIN-0.89PHT ceramics are systematically investigated. Based on Landau theory, we propose a novel strategy for obtaining high-performance ceramics by combining tetragonal phase and relaxor ferroelectrics. Results reveal that the introduction of polar nano-regions in tetragonal phase ceramics by doping with rare-earth ions to convert normal ferroelectrics into relaxed ferroelectrics is responsible for excellent properties of 0.11PIN-0.89PHT- x Nd ceramics. The optimized comprehensive performance is obtained at x = 0.9 mol%, where d 33 = 670 pC/N, S max = 0.29% (45 kV/cm), strain hysteresis = 8.68% (45 kV/cm), d 33 * = 736 p.m./V (30 kV/cm), T C = 312.6 °C, ε r = 3234, k p = 0.62, tan δ = 0.014, and excellent high-temperature stability in temperature range of 20–240 °C. After 106 cycles, electrical properties and strain remain unchanged, showing excellent anti-fatigue behavior. This work provides a novel approach for the development of ceramics with outstanding piezoelectric response, high strain, low strain hysteresis, excellent anti-fatigue resistance and thermal stability, and is expected to realize practical applications of piezoelectric ceramics. [ABSTRACT FROM AUTHOR]

The search for a suitable donor dopant to improve the piezoelectric response of BiScO 3 -PbTiO 3 (BS-PT) piezoelectric ceramics without sacrificing temperature stability is crucial for developing high-temperature piezoelectric materials for the application in the elevated temperature. In this study, the effects of Sb5+ donor doping on the microstructure, dielectric, ferroelectric, piezoelectric and electromechanical properties of the BS-PT ceramics were investigated. It was found that the Sb5+ dopant acts as the grain growth inhibitor, resulting in a dense and fine-grain microstructure. An enhanced piezoelectric properties d 33 of 535 pC N−1 with a high T c of 440 °C was simultaneously achieved in 0.25 mol%Sb5+ doped BS-PT (BSPT-0.25Sb) ceramic. The results of in-situ piezoelectric constants and electromechanical coupling coefficients as a function of temperature indicate that the BSPT-0.25Sb ceramic has a high depolarization temperature T d of 400 °C, which is much higher than those of the most widely used PZT-based piezoelectric ceramics. Furthermore, BSPT-0.25Sb ceramic has much higher resistivity and lower dielectric loss than PZT-4 and PZT-8 at high temperature. The excellent piezoelectric properties and thermal stability of the BSPT-0.25Sb ceramic indicate that it is a promising piezoelectric material for high-temperature applications. [ABSTRACT FROM AUTHOR]

Monatomic Sb thin films can eliminate the risks of compositional partitioning, but it normally crystallizes instantly and fails to maintain amorphous state at room temperature. Here, we prepared Sb x (Sb 2 S 3) 100-x thin films. The materials consist of pure Sb with low resistance drift and chalcogenide Sb 2 S 3 with high thermal stability. It is found that the Sb 64·8 (Sb 2 S 3) 35.2 thin film possesses the advantages of these two compounds. The thin film showed good phase-change ability with an ultralow resistance drift coefficient of 0.006, much lower than conventional Ge 2 Sb 2 Te 5 (0.076). Moreover, it also exhibited a better amorphous thermal stability. These improvements are closely related to the hybrid nanostructure of Sb crystals and Sb–S phase by spontaneous self-decomposition in the Sb-rich Sb–S material. Our work thus demonstrates that the binary Sb-rich Sb–S thin film can become a promising alternative to replace the conventional Ge 2 Sb 2 Te 5 thin film with potential for neuromorphic synaptic devices. [ABSTRACT FROM AUTHOR]

In this paper, the ceramics with composition of (0.98- x)(K 0.5 Na 0.5)(Nb 0.96 Sb 0.04)O 3 -0.02(Bi 0.5 Na 0.5)(Zr 0.8 Ti 0.2)O 3- x CaZrO 3 (abbreviated as (0.98- x)KNNS-0.02BNZT- x CZ, x = 0, 0.01, 0.015, 0.02, 0.025, 0.03) were prepared by a traditional solid-state reaction method. The effect of the additional amount of CaZrO 3 on the phase structure, microstructure, dispersion index, domain structure and piezoelectric properties of ceramics was systematically studied. Finally, the piezoelectric properties and thermal stability of ceramics could be controlled by adding different amounts of CaZrO 3. The addition of CaZrO 3 transferred the phase structure of the ceramics from orthogonal-tetragonal (O-T) coexistence phase to rhombohedral-orthogonal (R–O) coexistence phase, which could be demonstrated by XRD test, temperature-dependent Raman spectra and ε r ‐ T plot analysis. And when x = 0.02, the ceramics possessed the best piezoelectric and dielectric properties (d 33 = 253 pC/N, ε r = 1185, tan δ = 0.044). Such excellent electrical properties could be originated from the heterogeneous domain structure and small-size nano-domains of the ceramics. Moreover, with the increase of CaZrO 3 doping amount, the dispersion index of ceramics gradually increased from 1.404 to 1.871, which showed more obvious dispersion phase transition characteristics and improved the thermal stability of ceramics. Particularly, when x = 0.02, after annealing at a high temperature of 220 °C (close to its Curie temperature), the d 33 tested at room temperature remained above 85% of that without annealing. The results indicated that (0.98- x)KNNS-0.02BNZT- x CZ ceramic was a promising lead-free piezoelectric ceramic system. [ABSTRACT FROM AUTHOR]

Bioactive compounds from jaboticaba peel were adsorbed on microcrystalline cellulose isolated from sorghum bagasse (MCC) to maintain their antioxidant activities (AA), as they are sensitive to pH, temperature, light, and the presence of oxygen. For this reason, there are limitations to keeping them active during storage or industrial processing, and new processes need to be studied. The synthesis conditions of the adsorbent-bioactive complex formed by the adsorption process of total phenolic compounds (TPC) in MCC and their stability against temperature variation (90–130 °C) were analyzed. In the synthesis of the complex, it was observed that in the kinetic study, pseudo-second order model fitted the experimental data, and in the equilibrium isotherms, the Langmuir model best describes the synthesis. The thermodynamic parameters (ΔG ads , ΔS ads , and ΔH ads) showed that TPC interacts with MCC by chemical adsorption through a spontaneous and exothermic process. Approximately 90% of the TPC was released in the first 60 min of the aqueous desorption process. In the thermal stability study, the complex reduced the degradation of TPC and AA compared to jaboticaba peel powder, reaching a percentage of reduction in its degradation of 71% at a temperature of 130 °C. [Display omitted] • A way to stabilize total phenolic compounds in microcrystalline cellulose is presented. • Thermodynamic study showed that TPC interacts with MCC by chemical adsorption through a spontaneous and exothermic process. • The complex reduced the thermal degradation of total phenolic compounds in 71% at the temperature of 130 °C. • The complex reduced by approximately 58%, 52% and 31,8 the degradation by the DPPH, ABTS and FRAP assays. • The complex can be used in industrial processes that use high temperatures without losing its functional characteristics. [ABSTRACT FROM AUTHOR]

The impact of the crystallinity on structural, thermal, and in vitro dissolution properties were examined for Na 2 O-CaO-Nb 2 O 5 /MgO-P 2 O 5 glasses/glass-ceramics. Glass-ceramics were synthesized via a spontaneous crystallization process. The Nb content in the materials increased with melting temperature, furthermore, the crystallinity is proportional to the Nb content. The presence of crystalline niobates and phosphates is confirmed by FTIR analysis which is consistent with XRD. The FTIR results indicate that the phosphate network is built of different proportions of Q2, Q1, and Q0 units, depending on the amount and type of crystalline phase. Most of the samples show an improvement in thermal stability. The in vitro dissolution test showed that the highest mass loss for most of the samples occurred during the first 6 days of immersion in the PBS solution. The presence of small phosphate crystals favors the deposition of hydroxyapatite on samples' surfaces while the larger niobate crystals dissolve more readily. [ABSTRACT FROM AUTHOR]

Lignin can be used as a sustainable alternative to bisphenol A (BPA) to prepared lignin-based epoxy resins. Lignin effects including molecular weight, phenolic content, G/S unit ratio and flexible/rigid linkage ratio on epoxy synthesis and performance were summarized comprehensively. The incorporation of lignin with a higher molecular weight would lead to the higher rigidity of epoxy crosslinking network. Higher contents of ether bonds in lignin would provide higher structural flexibility of lignin incorporated epoxy thermosets. Lignin with higher contents of phenolic hydroxyls was more beneficial for improving the reactivity of its epoxy products after glycidylation. Due to the excellent charring capacity of lignin, higher contents of residue char can be produced at higher additions of lignin at high temperatures, while the loss of crosslinking density caused by the increasing lignin addition (especially for the macromolecular lignin) would deteriorate the thermal stability of their thermosets. Several applications of lignin-based epoxy resins were also mentioned based on their mechanical, thermal and chemical properties, such as coatings (with anticorrosion and UV-blocking), adhesives (with highly crosslinking network, excellent mechanical, and thermal properties) and flame retardants (with high charring capability). [Display omitted] [ABSTRACT FROM AUTHOR]

The major challenge of the current and future miniature compact high-tech electronic devices is thermal management. Micro-scale cooling is one of the promising thermo-fluidic implications possess a great potential in this cutting-edge research area. In this research work, newly emerged MXene (Ti 3 C 2) and functionalized graphene (f-Gr) hybrid nanoflake is implied for the first time in the preparation of Silicon oil (Si-oil) based heat transfer media (MXene:f-Gr/Si-oil hybrid nanofluid) for the micro-scale cooling application. This research concentrates on development, characterization, thermal stability and thermal properties evaluations of new class of hybrid (MXene:f-Gr/Si-oil) nanofluids of three different concentrations of MXene and f-Gr hybrid nanoflakes. The thermal conductivity of the as produced MXene:f-Gr/Si-oil hybrid nanofluids is measured (up to 250 °C) by a Transient Hot Bridge (THB) 500 (Linseis, Germany, current 5 mA, heater-power 18 mW) with Hot Point Sensor (HPS). The measurement is conducted in a newly customized designed industrial grade hotplate heat loss protection chamber with a PID controller. Viscosity is evaluated by a Rheometer with varying temperature of 25 °C from 25 to 125 °C. Optical absorbance is measure using PerkinElmer Lambda 750. The optimum thermal conductivity enhancement is acquired about ∼68% for the MXene and f-Gr hybrid nanoflakes concentration of 0.02 wt% over the pure Si-oil base fluid at 200 °C. The viscosity of MXene:f-Gr/Si-oil hybrid nanofluids is revealed to be autonomous of adding the MXene and f-Gr hybrid nanoflakes into the Si-oil base fluid. However, viscosity of hybrid nanofluid samples is decreased by ∼36% within the increase of temperature from 25 to 50 °C. MXene:f-Gr/Si-oil hybrid nanofluid sample of concentration 0.02 wt% shows the thermal stability up to ∼393 °C (∼14% enhancement over the Si-oil). This significant improvement is advantageous for the cooling of future high-tech electronic systems. This subsequently increases thermal energy acquisition which is valuable for various other applications. [Display omitted] • Synthesizing a unique MXene and f-Gr hybrid composition. • Novel formulation MXene:f-Gr/Si-oil hybrid nanofluids with improved heat transfer attributes. • High temperature thermal conductivity enhancement of new nanofluids using a heat-trap chamber. • Enhanced thermal conductivity of the new hybrid nanofluids over pure Si-oil. • Improved thermal stability of synthesized hybrid nanofluids. [ABSTRACT FROM AUTHOR]

The dissolution behaviour of three corn starches, including corn starch (CS), high amylose corn starch (HACS) and waxy corn starch (WCS) with different amylose content in 1-allyl-3-methylimidazolium chloride ([AMIM]Cl) and 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) were studied by comparing their dissolution state in ionic liquids (ILs). Further, the structural and thermal properties of the regenerated starch were analyzed. WCS with the lowest amylose content had the fastest dissolution rate, the most extensive structural damage, and the lowest solubility and required the maximum energy for dissolution. In the process of dissolution-regeneration, the A-type crystalline structure of WCS and CS was completely destroyed and transformed into an amorphous structure, while the B-type crystalline structure of HACS transformed into an ordered V -shaped structure. And the thermal stability of starch was improved after dissolution-regeneration in ILs. Among the two kinds of ILs, [AMIM] Cl had a better ability to dissolve starch, causing minor damage to the starch. [Display omitted] [ABSTRACT FROM AUTHOR]

• The photothermal conversion performance of Gd 0.7 Nd 0.3 BaCo 2 O 5+δ was better than that of Silicon Carbide which was commercial solar thermal conversion material. • Gd 0.7 Nd 0.3 BaCo 2 O 5+δ had low infrared radiation heat loss at high temperature. • Gd 0.7 Nd 0.3 BaCo 2 O 5+δ exhibited excellent thermal stability at 800 ℃ in air. The efficiency of the concentrated solar power (CSP) framework is significantly influenced by the operating temperature. The solar thermal conversion material with high efficiency and good stability at high temperature in air environment is of importance to obtain the high operating temperature. Here, the optical properties and thermal stability of Gd 1-x Nd x BaCo 2 O 5+δ (0 ≤ x ≤ 0.4, GNBCOx) ceramics were studied to assess their possibility to be applied as high temperature solar absorbers. Results presented that GNBCOx exhibited high absorptance in the solar spectrum and minimal radiation heat loss at infrared wavelengths. In addition, the GNBCOx ceramics demonstrated excellent stability at 800 ℃ in air, indicating that the GNBCOx ceramics could be applied as solar thermal conversion material for upcoming concentrated solar power systems. [ABSTRACT FROM AUTHOR]

Timoho fiber (TF) is a biodegradable bio-fiber rich in cellulose and a renewable agro textile fiber rich in cellulose polysaccharides. Isolation of micro cellulose from TF is an alternative reinforcement approach in a bio-composite application. This study characterized TF obtained from isolation employing FTIR, XRD, SEM-EDS, and TGA using hydrolysis. Pretreatment was done using alkaline, bleaching, and hydrolysis. FTIR confirmed that the maximum amount of noncellulosic materials had been removed from TF. The XRD result showed that hydrolysis treatment increased the crystal size and crystallinity index of the TF (88.68 %). TGA also revealed that the highest thermal stability had been found in the hydrolyzed TF. The micro cellulose TF represented an interesting source of cellulose reinforcing materials, and it might be continued in the form of nano cellulose. [ABSTRACT FROM AUTHOR]

Mn doping and S-evaporation are strategies used to improve the thermoelectric properties and thermal stability of cuprous sulfide thermoelectric materials. Cu 1.8 S and Mn-alloyed Cu 1.8 S powders were prepared via ball milling, and different samples were obtained via current-assisted sintering at different times. It was found that Mn and S-evaporation optimized the carrier concentration and thus improved the figure of merit (ZT) of the samples. The introduction of pore defects induced by S-evaporation also improved the ZT. The maximum ZT of the optimized sample reached 0.89 at 500 °C. Mn in the samples reacted with oxygen to form an oxide film on the surface of the block, which inhibited the kinetic process of Cu 1.8 S decomposition and improved the thermal stability of the samples. However, the reaction between Mn and oxygen led to a continuous loss of metal cations in the material, resulting in changes in the thermoelectric properties. [ABSTRACT FROM AUTHOR]

Herein, high-performance 0.11 Pb(In 1/2 Nb 1/2)O 3 -0.89 Pb(Hf 0.47 Ti 0.53)O 3 -0.8Ta 2 O 5 (PIN-PHT-0.8Ta) ceramics are successfully synthesized. In addition, performance improvement is comprehensively analyzed from viewpoints of microstructure, phase structure and electrical properties. Experimental results reveal that the addition of Ta 2 O 5 changes phase structure of PIN-PHT ceramics from ferroelectric tetragonal phase to rhombohedral phase. This leads to the appearance of morphotropic phase boundaries (MPBs). At the same time, the addition of Ta 2 O 5 reduces grain size and enhances grain uniformity. Also, Ta 2 O 5 doping improves internal and external contribution of piezoelectric response, which greatly improves dielectric, piezoelectric and ferroelectric properties of PIN-PHT. Key performance parameters include d 33 , k p , T C , ε r and tan δ , which are found to be 630 pC/N, 0.73, 322.6 °C, 1917 and 1.55%, respectively. In particular, thermal stability of PIN-PHT-0.8Ta ceramics is found to be higher than PZT-based ceramics, as well as d 33 value and performance retention rate of PIN-PHT-0.8Ta are found to be 560 pC/N and 89% at 300 °C, respectively, which are far superior to commercial PZT-5 and PZT-8 ceramics. These properties indicate potential of PIN-PHT-0.8Ta ceramics in high-temperature applications. [ABSTRACT FROM AUTHOR]

Red grape pomace was used as a source for poly(3-hydroxybutyrate) (PHB) production, which was then subject to a range of purification processes. The different PHB biopolymers were characterized for chemical structure, crystallinity, thermal properties, colour, release of compounds into different food simulants and antioxidant inhibition, and comparisons were made with a commercially available PHB. An increase in purification steps did not have a significant effect on the high thermal stability of the extracted biopolymer, but it decreased the degree of crystallinity and the presence of amino acids and aromatic compounds. With additional purification, the PHB powders also whitened and the number of components released from the biopolymer into food simulants decreased. The released compounds presented antioxidant inhibition, which has not been previously reported in the literature or with commercially available polyhydroxyalkanoates. This is of great interest for food packaging and biomedical industries where the addition of antioxidant additives to improve PHB functional properties may not be necessary and could be avoided. [Display omitted] • Red grape pomace was used as a source for poly(3-hydroxybutyrate) (PHB) production. • The extracted PHB was then subject to a range of purification processes. • Crystallinity reduction was observed with further purification steps. • Aromatic impurities found in PHB migrated into hydrophilic food simulants. • The migrated impurities showed antioxidant activity. [ABSTRACT FROM AUTHOR]

The effects of gelatinization at three selected temperatures (DSC characteristic peaks temperature: T O , T P , and T C) and subsequent cold storage (CS) treatment on structural characteristics, pasting, and rheological properties of maize starch (MS) were investigated. The pasting, rheological properties of MS was changed with the increase of gelatinization temperature from T O to T C , but were not further significantly changed if the gelatinization temperature was higher than T C. Pasting and thermal properties analysis suggested that gelatinization at T C (TC treatment) significantly increased the gelatinization and pasting temperature of MS. Moreover, TC treatment decreased breakdown viscosity by 8.49 times and setback viscosity by 2.53 times. Dynamic rheological measurements revealed that the TC treatment caused the lower G' and G" of MS, and decreased the thickening coefficient by 55.17 %. These results indicated that TC treatment could enhance the thermal stability properties of MS, inhibiting the shear and short-term retrogradation, the shear-thinning behavior of MS. Interestingly, the CS treatment further inhibited the shear and short-term retrogradation and the shear-thinning behavior of MS. The leaked starch molecules aggregate to form a harder structure after gelatinization and starch molecules were further aggregated after CS treatment, these all were hypothesized to be responsible for these results. • Gelatinizations significantly changed the properties of maize starch. • Gelatinization at T C more effectively improved thermal and rheological properties. • Gelatinizations and cold storage inhibited shear and short-retrogradation. • Gelatinizations caused the starch leakage and aggregate to form a harder structure. [ABSTRACT FROM AUTHOR]

This study presents the preparation of cellulose micro-nanofibrils (CMNFs) from Enteromorpha (EP) and the application in PVA/acetylated distarch phosphate (ADSP)/CMNFs composite films. The Micro-nano scale, hydrophilicity, and strong hydrogen bond characteristics of CMNFs prepared form EP by acid hydrolysis were confirmed through the granular statistics, XRD analysis and chemical structure analysis. With the addition of CMNFs, the ultimate tensile strength and elongation at break of composite films are increased by 42.4 % and 90.3 %. An original Weibull statistical analysis shows the impact of CMNFs' added amount on strength distribution and ultimate stress. SEM and polarizing microscope images show the CMNFs' dispersion state in that films is optimal, when their addition was to be 2 %–3 % of total dry weight of PVA/ADSP matrix， which is consistent with the results of Weibull modulus analysis. The main thermal weight-loss process of the composite film is divided into four stages, CMNFs can significantly increase the thermostability at 280 °C to 400 °C. The experiment of water contact angle and water vapor transmission rate of the composite films confirmed that CMNFs can improve films' hydrophilicity. This study provides basis for the preparation of hydrophilic CMNFs and mechanism of modification study PVA-based composites. • High hydrophilic cellulose micro-nanofibrils prepared from Enteromorpha seaweed • The PVA based composite films modified by those fibrils have excellent performance. • Excellent hydrophilicity, mechanical properties, and improved thermal stability • Combining scanning electron and polarizing microscope to judge the morphology [ABSTRACT FROM AUTHOR]

Soybean meal, an agro-industrial by-product is rich in protein and can be used as a potential source of protein isolate. In the present work, protein isolate was extracted from soybean meal by ultrasound treatment and pH was adjusted to 2, 4, 6, 8, and 10. Ultrasonic extraction of protein isolates resulted in maximum yield and purity of 41 ± 2 % and 92 ± 2% respectively at optimized ultrasound conditions. Soybean meal protein isolates adjusted at pH 10 showed reduced particle size, increased solubility, high emulsifying, foaming, water, and oil binding properties. Structural characteristics of pH adjusted soybean meal protein isolate studied by FTIR and XRD indicated increased changes of secondary structures and less crystallinity of protein after pH adjustment. SEM and TEM analysis indicated the formation of a more aggregated structure of protein in pH adjusted samples compared to the control. The soybean meal protein isolates sample adjusted at pH 10 showed higher thermal stability with a denaturation temperature of 123 ± 2 °C as compared to those samples adjusted pH at 2, 4, 6, and 8. Thus, pH adjustment can be adopted as a potential method for the improvement of soybean meal protein and increase its applicability in a wide range of food product development. [Display omitted] • Different pH shifting (4−10) treatments were given to the ultrasonically obtained soybean meal protein isolate (SMPI). • SMPI obtained by shifting pH at 10 showed the highest solubility and lowest particle size. • Functional and structural properties showed significant improvement when the pH of SMPI shifted at 10. • Thermal stability was found higher in SMPI obtained by shifting pH at 10. [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]

As an essential enzyme for phospholipid degradation, phospholipase C (PLC) has been used for enzymatic degumming of vegetable oils and production of valuable phospholipid derivatives. In this study, rational engineering based on B-factor analysis and molecular dynamic simulation analysis were employed to rationally identify mutation candidates and a PLC double mutant F96R/Q153P was designed from Bacillus cereus HSL3. Compared to the wild-type PLC, F96R/Q153P exhibited significantly improved thermal properties, including higher temperature optima and better thermal stability. It showed the highest optimal reaction temperature (90 °C) reported so far. F96R/Q153P displayed 4.94 times kcat and 2.37 times k cat /K m as much as the wild-type, as well as improved substrate adaptability. Structural insights revealed that the mutations caused reduced proportion of random coil and constraint of certain loop fluctuations. These results demonstrated the great potential of knowledge-based rational design for improving the catalytic characteristics of industrial enzymes in the enzymatic degumming process. [Display omitted] • Rational engineering was used to increase the thermal stability and activity of PLC. • The optimal temperature was 90 °C which represented the highest one up to date. • Structural insight revealed the molecular basis for performance improvement of PLC. [ABSTRACT FROM AUTHOR]

The use of inert gases such as nitrogen continuously during torrefaction causes a burden in terms of operational cost. Therefore, a novel concept of mild pressurization has been introduced to eliminate the dependence on the inlet gas completely. In the present study, the torrefaction of fibrous empty fruit bunch (EFB) was performed for various temperatures of 250 °C–300 °C and residence times of 30–90 min. The pressure exerted by the load during torrefaction was 0.0230 MPa. The results show that torrefaction temperature is a dominant parameter in affecting physical and physicochemical properties as well as thermal stability of the torrefied EFB rather than residence time. An increase in temperature causes an improvement in gross calorific value, hydrophobicity, atomic H/C and O/C ratios as well as thermal stability. Besides, it was found that the EFB experiences a significant change after torrefaction at temperature of 300 °C in terms of surface, microstructure, crystallographic structure and functional groups. This is mainly due to the significant decomposition of the main biomass constituents especially hemicellulose and cellulose. Overall, it can be concluded that the best performance was obtained at torrefaction temperature of 300 °C and residence time of 90 min. [Display omitted] [ABSTRACT FROM AUTHOR]