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High-entropy ceramics have garnered significant attention in recent years owing to their exceptional properties and structural diversity. In this work, single-phase medium/high entropy ceramics, namely (Ca 0.2 Sr 0.4 Ba 0.4)(Zr 0.5 Ti 0.5)O 3 and (Ca 0.2 Sr 0.4 Ba 0.4)(Zr 0.1 Ti 0.9)O 3 , were successfully designed and prepared utilizing Spark Plasma Sintering (SPS). A comprehensive investigation was conducted into the phase structure, microscopic morphology, dielectric properties, and thermal behavior of these ceramics. It was observed that all ceramics maintained a cubic perovskite structure (space group: Pm 3 ‾ m), and the introduction of multi-element doping rendered them more stable across a wide frequency and temperature range. Notably, (Ca 0.2 Sr 0.4 Ba 0.4)(Zr 0.5 Ti 0.5)O 3 exhibited remarkably low dielectric loss (0.0001 at 1 kHz) at room temperature, along with excellent dielectric temperature stability (25–400 °C). By reducing the zirconium concentration in (Ca 0.2 Sr 0.4 Ba 0.4)(Zr 0.1 Ti 0.9)O 3 , a slight decrease in dielectric temperature stability was observed (25–350 °C); however, it demonstrated lower thermal conductivity (0.41 W/(m·K), 1200 °C) and maintained good high-temperature stability. The discovery highlights the promising practicality of both ceramics for high-temperature dielectric applications. [ABSTRACT FROM AUTHOR]

Borophosphosilicate glasses with varying sodium ion concentrations were investigated for their, structural, thermal, and electrical properties. All the obtained glasses were transparent except the glass with the highest sodium content, which exhibited translucency due to inhomogeneities. Increasing sodium content led to reduced boron and silicon content while maintaining a constant B/Si ratio, indicating progressive depolymerization of the glass network. Confocal microscopy, scanning electron microscopy, and atomic force microscopy showed homogeneous and granular structure for samples with lower sodium content, but higher sodium content resulted in visible agglomeration/nanocrystallization. X-ray diffractograms showed amorphous nature for most samples, with samples doped with the highest concentrations of Na 2 O showing several broad reflections suggesting nanoscale crystallinity. Fourier-transform infrared spectroscopy revealed shifts in dominant bands with increasing sodium content, indicating depolymerization of the borate network. An observed decrease in glass transition temperature and thermal stability with increasing sodium content was attributed to depolymerization and formation of non-bridging oxygens. Impedance spectroscopy revealed two relaxation processes associated with the transport of Na+ ions through two different regions. DC conductivity and activation energy predominantly increased with the sodium ion content at high temperatures. [ABSTRACT FROM AUTHOR]

Aluminum nitride (AlN), prized for its high thermal conductivity and electronic insulating properties, finds widespread use in electronic applications, particularly as a substrate material. However, its relatively low fracture toughness limits its application. In this study, to enhance both the thermal and mechanical properties of AlN ceramics, we thoroughly investigate the microstructure, thermal, and mechanical properties of self-reinforced AlN ceramics fabricated by spark plasma sintering, with self-reinforcement achieved through the integration of AlN whiskers within the AlN matrix. Unlike previous studies utilizing conventional pressureless sintering with limited sintering conditions, this work employs spark plasma sintering with a wide range of temperatures (1600–1900 °C) and holding times (10–30 min), providing a comprehensive understanding of the sintering behavior. Microstructural features, observed through optical and scanning electron microscopy, reveal distinct toughening mechanisms via crack deflection and branching, with a maximum 20% enhancement. The self-reinforced AlN ceramics exhibit remarkable improvements in thermal conductivity, reaching up to 150 W m−1 K−1, surpassing reported values for spark plasma-sintered AlN ceramics. Adding AlN whiskers enhances the thermal and mechanical properties of AlN simultaneously, particularly at 1800 °C for 10 min with controlled grain size and nicely integrated AlN whiskers. This work not only contributes valuable insights into the complex relationship between processing parameters, microstructure, and resulting thermal and mechanical properties but also highlights the enhanced thermal and mechanical properties of self-reinforced AlN ceramics. [ABSTRACT FROM AUTHOR]

Addressing the issue of carbon contamination during the smelting of specialty metals or alloys, utilizing graphite crucibles, has attracted considerable research attention, prompting the exploration of novel ceramic crucible materials. AlN ceramic, renowned for their exceptional high-temperature stability and resistance to corrosion, have emerged as promising candidates to mitigate this concern. Nonetheless, the limited mechanical properties and thermal shock resistance of AlN curtail its widespread application. In this study, Y 2 Zr 2 O 7 was introduced as an additive to enhance AlN's properties, and AlN-based composite ceramics were fabricated by employing pressureless sintering. The effects of Y 2 Zr 2 O 7 addition (3–10 wt%) on the mechanical properties and thermal shock resistance of the resulting composites were examined. The findings revealed that the incorporation of 5 wt% Y 2 Zr 2 O 7 (AlN-5YZO) led to the highest relative density and a refined grain structure, resulting in superior mechanical properties. Notably, the flexural strength, fracture toughness, and Vickers hardness of AlN-5YZO reached 322 MPa, 3.70 MPa m1/2, and 13.34 GPa, respectively. Furthermore, the presence of crack branching and crack deflection within the composite ceramics impeded crack propagation, effectively augmenting their thermal shock resistance. AlN-5YZO samples exhibited residual strength retention rates of 91.0 %, 84.2 %, and 76.7 % after 10, 20, and 50 thermal shocks between 1000 and 1600 °C, surpassing those of pure AlN. The findings of this study present promising avenues for advancing crucible materials tailored for high-temperature applications. [ABSTRACT FROM AUTHOR]

Multi-layered graphene and graphene oxide have been used as reinforcements in nanodevices and nanocomposites due to their extraordinary mechanical and thermal properties. However, compared to graphene, graphene oxide has a lower Young's modulus and lower thermal conductivity. Nanodevices and nanocomposites based on multi-layered graphene and graphene oxide require different mechanical properties and thermal conductivity. This study employed molecular dynamics simulation to investigate 10 models of multi-layered graphene and graphene oxide (in the form of different layer arrangements) in single, double, and triple layers. The results showed that an increase in the number of graphene oxide layers leads to irregularities in the nanosheets, resulting in decreased thermal conductivity (by 64.4%) of the nanosheets decreases. Furthermore, the greater number of graphene layers in multi-layer nanosheets resulted in an increase in Young's modulus (by 79.3%) and tensile strength (by 73.7%). Moreover, the arrangement of graphene and graphene oxide is a crucial factor that can significantly impact the mechanical properties and thermal conductivity of the models. Moreover, an increase in temperature can lead to a decrease in Young's modulus of multilayered nanosheets. Increasing the number and size of graphene layers enhances both the ultimate tensile strength and the critical energy release rate. [ABSTRACT FROM AUTHOR]

The novel plasma ageing technique has been used to investigate the effects of different treatment times of a co-polymer reinforced with montmorillonite nanoclay, where the effects of plasma ageing of the reinforced acrylic co-polymer (BA, STY and MAA) were obtained with nanoclay (sodium MMT) at different concentrations. The molecular weights of the samples were obtained by observing the change in the viscosity of the nonreinforced polymers, as well as an analysis of the thermal properties using the thermogravimetric analysis technique to determine their thermal stability, which showed an early decomposition of the exposed nanoreinforced materials to plasma concerning the reference sample 0 min. The differential scanning calorimetry analysis showed an increase in the glass transition temperature when adding the nanoreinforcement, but a decrease with saturation, likewise, it was observed that when adding this nanoreinforcement (MMT) to the polymeric matrix this protects the matrix when exposed to plasma. This acquires an increase in elastic modulus, which indicates a fragility in the nanomaterial. The structure of the nanocomposite was studied by means of the X-ray diffraction technique of the samples exposed to plasma treatment, obtaining patterns where intercalated nanocomposites are present. [ABSTRACT FROM AUTHOR]

Ternary half-Heusler (HH) alloys are under intense investigations recently towards achieving high thermoelectric (TE) figure-of-merit (ZT). Of particular interest is the ZrNiPb-based HH alloy, where an optimal value of ZT ~ 0.7 at 773 K has been achieved by co-doping Sn and Bi at Pb site. In this work, we identify an excellent ZT of 1.3 in ZrNi1+xPb0.38Sn0.6Bi0.02 (x = 0.03, at 773 K) composite alloy. This is achieved by synergistic modulation of electronic as well as thermal properties via introduction of minor phase of full-Heusler (FH) in the HH matrix through compositional tuning approach. These Ni-rich ZrNi1+xPb0.38Sn0.6Bi0.02 (0 ≤ x ≤ 0.07) alloys were synthesized via energy efficient and time-curbed techniques that involved Arc melting followed by consolidation via spark plasma sintering. These alloys were characterized by XRD and SEM, which show formation of nanocomposites comprising of HH matrix phase and FH secondary minor phases. Enhancement in ZT is mainly attributed to a synchronized increase in power factor (~42%) and ~25% decrease in its thermal conductivity. Here, TE compatibility factor (S) was also calculated for all samples. The value of |S| ~ 2.7 V−1 (at 773 K) is observed for x = 0.03, which is ~17% higher than bare HH composition (x = 0.0). The theoretically calculated TE device efficiency of best-performing sample ZrNi1.03Pb0.38Sn0.6Bi0.02 is estimated to be η ~ 13.6%. Our results imply that deliberately controlled fine tuning in compositions of HH compounds through compositional tuning approach would lead to novel off-stoichiometric HH phases with enhanced ZT value for efficient TE device fabrication. [ABSTRACT FROM AUTHOR]

Polypropylene multifilament yarns produced with flame-retardant (FR) additives have a significant place in the technical textile market. Determination of the technical performances of these multifilaments is very important. In addition, effects of the additive in the filament structure on the thermal and structural properties of the filament must be examined. In this study, new polypropylene polymer (PP) filament yarns having FR properties were produced and their thermal properties and crystallization data were determined and results are interpreted. Thermal properties and crystallization data of the PP multifilament yarns were determined by DSC analysis. Further, values of crystalline region ratio were determined and thermogram graphs of all samples were interpreted. As can be seen from the graphs, PP filaments had two consecutive melting points because PP has a double melting peak due to its structural character. Also, it has been observed that there is a direct proportionality between the melting enthalpy values of PP filaments and crystalline region ratios (%). The melting point was not significantly affected by the amount of FR additive. The addition of FR granule to PP filament further increases the enthalpy (∆Hm) required to melt the filament but there was no effect on melting temperature due to loading of FR additive to the PP filament yarns. Also, mechanical properties (tenacity and breaking elongation) and unevenness values were determined. [ABSTRACT FROM AUTHOR]

In the years 2022 and 2023 we investigated the prevalence of the ovulatory failure in 133 mares of different breed, 3 to 24 years old, brought to the Equine clinic of the University of Veterinary Medicine and Pharmacy (UVMP) in Košice. Our research involved the monitoring of the reproduction cycle in these mares with the aim to determine the prevalence of ovulatory failure during the breeding season, focusing on certain specific parameters that were considered sufficiently relevant with respect to the development of such failure. These parameters included environmental temperature and the amount of daylight the mares were exposed to, attributable to the months of the breeding season. In addition, we also evaluated the size of pre-ovulatory follicles and the influence of age of the investigated mares. During the mentioned years, one of the ovulatory failures occurred in 17 out of 133 mares (12.78 %). Examination by ultrasonography (USG) and the subsequent analysis of the occurrence of failures in relation to the investigated parameters allowed us to conclude that the length of daylight, age, and environmental temperature were the most important factors. Our observations indicated that the 15–16 h category of daylight presented the highest risk of development of cycle disorders with the most rapid increase observed for HAF. With respect to age, the highest occurrence of ovulatory failures was observed in the category of 15–24 years. The external temperature in the range of 18.1–23.0 °C affected the most the development of cycle disorders. Again, the effect was most evident with respect to HAF. This resulted in our recommendations for horse breeders that they should manage reproduction of their mares in a way so that the receptive phase of the cycle does not occur in the months during which the daylight length and environmental temperatures support ovulatory failure. We also recommend that if the owner′s wish is to keep in the breeding the mares older than 15 years, regular thorough gynaecological examination of these animals should be ensured, aimed at early diagnosis of ovulatory failure. [ABSTRACT FROM AUTHOR]

The food and beverage industry worldwide is trying to switch to using environment-friendly and bio-degradable materials in food packaging to avoid environmental concerns of using petroleum-derived plastic (synthetic polymers) materials. In this study, chitosan (CH) hydrogel films were fabricated by using its derivative chitooligosaccharides (COS) as an additive, polyvinyl alcohol as a plasticiser, and bioactive gallic acid as a cross-linker. The physical, mechanical, structural, barrier (e.g., moisture, water vapour permeability (WVP), and UV-barrier property), thermal properties, and biodegradation patterns of fabricated films were investigated. The use of bio–composite in CH films exhibited a synergistic effect. A film with a homogenous/smooth surface and excellent mechanical and thermal properties was obtained. Additionally, incorporating COS and gallic acid reduced the moisture content, WVP, and transparency. Moreover, the films exhibited good colour, strong UV-barrier properties, and good biodegradable capacity in soil. The results suggest that eco-friendly CH hydrogel films have promising potential to be used in food packaging. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering (17264073) is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The energy consumption of buildings presents a significant concern, which has led to a demand for materials with better thermal performance. Thermal conductivity (TC), among the most relevant thermal properties, is essential to address this demand. This study introduces a methodology integrating a Multilayer Perceptron (MLP) and a Generative Adversarial Network (GAN) to predict the TC of concrete based on its mass composition and density. Three scenarios using experimental data from published papers and synthetic data are compared and reveal the model's outstanding performance across training, validation, and test datasets. Notably, the MLP trained on the GAN-augmented dataset outperforms the one with the real dataset, demonstrating remarkable consistency between the model's predictions and the actual values. Achieving an RMSE of 0.0244 and an R2 of 0.9975, these outcomes can offer precise quantitative information and advance energy-efficient materials. [ABSTRACT FROM AUTHOR]

Battlefield wounds are at high risk of infection due to gross contamination and delays in evacuation from forward‐deployed locations. The aim of this study was to formulate an antibiotic wound gel for application by a field medic in austere environments to protect traumatic wounds from infection during transport. Formulation development was conducted over multiple phases to meet temperature, handling, in vitro elution, and in vivo tissue response requirements. Thermal properties were evaluated by vial inversion, DSC, and syringe expression force in a temperature range of 4–49°C. Handling was evaluated by spreading onto blood‐contaminated tissue and irrigation resistance. Controlled antibiotic release was evaluated by a modified USP immersion cell dissolution method. Local tissue effects were evaluated in vivo by subcutaneous implantation in rats for 7 and 28 days. An oleogel composition of cholesterol, hydrogenated castor oil, soybean oil, and glyceryl monocaprylocaprate met the target performance criteria. Peak expression force from a 5 mL syringe at 4°C was 48.3 N, the dropping point temperature was 68°C, and the oleogel formulation could be spread onto blood‐contaminated tissue and resisted aqueous irrigation. The formulation demonstrated sustained release of tobramycin in PBS at 32°C for 5 days. Implantation in a rat dorsal pocket demonstrated a slight tissue reaction after 7 days with minimal to no reaction after 28 days, comparable to a commercial hemostat control. Material resorption was evident after 28 days. The formulation met target characteristics and is appropriate for further evaluation in a large animal contaminated blast wound model. [ABSTRACT FROM AUTHOR]

Legume flours are an increasingly popular food ingredient. Thermal treatments applied prior to milling legumes and granulometry can modify flour properties, altering sensory, digestibility and functional attributes. Raw and treated (soaked and cooked) lentil flours of different granulometry were produced. The applied treatment resulted in an increase in fiber content (25.4 vs. 27.6% for raw and treated lentil flour, respectively) and water absorption capacity. It also led to a decrease in ash content (3.3 vs. 1.8% for raw and treated, respectively) and a darker flour. Treated lentil flour was mainly composed of fractions of high granulometry, which could be beneficial for products where a lower glycemic index is sought, as they demonstrated higher fiber and lower carbohydrate content than the finer fractions. Treated flour may be used as an ingredient in the development of raw products, including beverages and desserts, due to its reduced anti-nutritional compounds' content and enhanced organoleptic aspects. The obtained results allow an in-depth characterization of raw and treated lentils flour with different particle sizes to consider a formal and complete standardization of these flours and for understanding their utility and specific food applications. [ABSTRACT FROM AUTHOR]

In this study, it was aimed to achieve an enhanced epoxy by reinforcing with nanoparticles obtained from waste materials with the concept of waste management. Firstly, Ce2O3 and SrO nanoparticles were synthesized by the green synthesis method using walnut (Juglans Regia L.) husk extract. Epoxy composites were prepared by reinforcing Cerium (III) oxide (Ce2O3) and Strontium oxide (SrO) nanoparticles produced by the green synthesis method at the reinforcement ratios of 0.3, 0.6 and 1% by weight, and it was aimed to determine the flexural strength properties. The chemical and structural compositions of the composites prepared by reinforcing Ce2O3 and SrO nanoparticles were analyzed using Scanning Electron Microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). In addition, the thermal stability of nanocomposites was determined using thermo-gravimetric analysis (TGA) and Differential Scanning Calorimetry (DSC). It was observed that a 21% increase occurred in the flexural strength of 0.3%wt SrO composites compared to the neat specimens. The thermal properties of nanocomposites produced by reinforcing the nanoparticles at different ratios compared to the neat specimens have improved. In TGA analyses, the highest residual mass of 0.1%wt Ce2O3 composites was observed as 16.13%, while it was determined as 14.53% in 0.6%wt SrO composites. Thus, it has been observed that nanocomposites obtained with food wastes are suitable for use in the composite industry. [ABSTRACT FROM AUTHOR]

Biochar-based composites have proven to be the best solution to enhance the mechanical and thermal properties of polymeric composites. This paper presents the biochar produced from Anacardium occidentale nut shell (AONS) treated with alkaline materials. Composites were developed using the solution casting method at different weight proportions of untreated and alkali-treated AONS biochar/vinyl ester resin (VER). Thermal properties like thermogravimetric analyzer (TGA), differential scanning calorimetry (DSC), dynamic mechanical analyzer (DMA), and mechanical properties such as tensile, flexural, and impact. Electrical properties were carried out for the composites. DSC results showed the crystallization temperature of untreated and treated VER/15wt%. AONS composites are 13% and 19% higher than pure vinyl ester. Mechanical studies showed that treated and untreated AONS biochar/VER composite samples were increased significantly compared to the pure vinyl ester sample. More importantly, 15wt% of alkali-treated biochar-added composites obtained higher properties than the other composites. These make the AONS an exciting approach to developing a sustainable energy system. [ABSTRACT FROM AUTHOR]

This study looked at the mechanical, electrical, and thermal surface conductivity of a polyester composite reinforced with flax fiber and thermally reduced carbon quantum dots. The primary objective of this work was to ascertain how incorporating carbon dots from thermally reduced biomass sugarcane bagasse enhanced the qualities of the polyester composite and resulted in its development as a sustainable material for cutting-edge applications. By pyrolyzing sugarcane bagasse, carbon dots were produced, and then hand layup was used to create the composites. After that, the effects of the addition of carbon dots were evaluated by testing the composite material in accordance with the American Society for Testing of Materials (ASTM) criteria. The findings demonstrated that increasing the amount of carbon dots in a polyester composite by up to 5 vol.% increased its tensile, flexural, and impact strength. However, the properties changed when the carbon dots content was raised to 7 vol.%. The highest hardness of the 7 vol.% carbon dots distributed composite, in contrast, was 82 shore-D, and its specific wear rate was reduced at 0.005 mm3/Nm. The dielectric constant and dielectric loss are both at their maximum values in the 7 vol.% carbon dots dispersed composite, at 4.1 and 0.15, respectively. This polyester composite also exhibits excellent thermal conductivity (0.394 W/mK), demonstrating effective heat transfer bridge development. Thus, these polyester composites with better surface conductivity (electrical, thermal, and hydrophobicity) and mechanical properties could be employed as a functional material for electrical and thermal applications. [ABSTRACT FROM AUTHOR]

This study aimed to create a high flame retardant, load bearing and thermally stable epoxy composite for various engineering applications. To achieve this, cashew nut shell de-oiled cake derived biosilica and satin weaved sunn hemp fibre was utilized as reinforcements along with epoxy resin. The biosilica is prepared using thermo-chemical process, whereas the satin weaved sunn hemp fibre was made using hand loom. Furthermore, the composites were manufactured by the hand lay-up method and characterized in line with the ASTM standards. According to the results, the lowest value of combustion rate is approximately 11.93 mm/min for the composite designation RSB3. The addition of sunn hemp fibre and 3.0 vol. % of biosilica composite (RSB2) yielded a tensile strength of 164 MPa, flexural strength of 204 MPa and modulus of 6.21 and 6.82 GPa, respectively. It is noted that the thermal conductivity improved marginally when the biosilica is added into the composite. Furthermore, adding cashew nut shell biosilica decreases the specific wear rate of the composites. Such natural fibre composite with high resistances to heat as well as mechanical load and thermal stability could be employed in automobiles, industries making consumer and electronic goods as well as sports applications. [ABSTRACT FROM AUTHOR]

Filler components play a crucial role as thermo‐mechanical reinforcement to the epoxy‐based solder mask, ensuring effective insulation and passivation. This study investigates the impact of different inorganic filler types (talc, silica (SiO2), boron nitride (BN) and barium sulfate (BaSO4)) and loadings (5 and 15 wt%) on the tensile and thermal properties of the epoxy composites. The composites were blended, cast and thermally cured. Of these composites, only 15 wt% SiO2/epoxy composite exhibits notable increments in both tensile strength and modulus, surpassing unfilled epoxy by 11.65% and 31.9%, respectively. It also displays the highest elongation at break, supported by small particle size, high specific surface area and minimal void volume fraction. For thermal tests, the addition of all fillers increases the storage modulus in both glassy and rubbery regions, especially 15 wt% talc/epoxy composite with 30.09% increment at 25 °C. Additionally, all fillers raise the glass transition temperature (Tg), notably improving it by 9 °C in the 15 wt% BN/epoxy composite. Moreover, their inclusion generally enhances the onset decomposition temperature (Tonset) and reduces weight loss during decomposition. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

A fundamental requirement for analysing timber structures under fire is to consider the degradation of material properties with temperature. Therefore, the objective of this study is to propose a model that accounts for the variation of the thermo-physical properties, the development of char, and its evolution with temperature. This model integrates a sequential coupling of heat transfer analysis with structural response. The degradation of the material properties is accounted for through the regulatory approach recommended in Eurocode 5. The stress analysis employs an elasto-plastic model with nonlinear isotropic hardening. Implementation of the model is achieved within the Abaqus suite of finite element software using external subroutines. The model's predictions align well with experimental data, accurately reproducing both thermal and structural responses. Specifically, the model accurately predicts temperature profiles, displacements, and the depth of the charred layer, which initiates above 300 °C. Additionally, for rectangular sections, it was observed that exposure of all faces to fire results in a non-rectangular residual section. Furthermore, employing the temperature-dependent thermal property curves suggested by EC5 yields satisfactory results when predicting the fire resistance of softwood timber structures. [ABSTRACT FROM AUTHOR]

This paper presents an experimental and numerical study of the freezing-thawing behavior of water in fully saturated sand. A relatively inexpensive and easily replicable experimental procedure was developed to simulate the freezing-thawing cycles in a medium-sized sand sample placed in a modified commercial freezer. By insulating the sides and bottom of the sample well, while allowing good thermal conductivity at the top of the sample, a nearly vertical advance of the freezing and thawing front was achieved. A series of freeze-thaw cycles were performed with higher and lower temperature gradients. A numerical multiphysics model, assuming an axially symmetric geometry based on the transient heat transfer during the phase transition, used a parametric approach to estimate the effective thermal properties of the sand-water-ice system. A good agreement between experimental and modelling results was shown, but slightly different parameter sets were obtained for each temperature gradient. The presented method could be a simple way to characterize the freeze-thaw process in natural and artificial porous materials. [ABSTRACT FROM AUTHOR]

The segment character of polyurethanes (PUs) determines the micromorphology and properties. The effective segment regulation can customize the favorable performance of PUs. Herein, silicon covalent‐modified polyurethanes (MPUs) were prepared by incorporating diphenylmethane diisocyanate (MDI) and diphenyl silanediol (DPSD) into PU molecules as hard segments via a two‐step method. Distinctive microphase separation structures from sheet morphology to radial sheet or withered flower‐like microdomain were formed by adjusting hydrogen bonding of hard segments and post‐treatment techniques. Thus, with the addition of DPSD in hard segments, the thermo‐optic responses for MPUs occurred due to the different microphase evolution under thermal effect. And with the further addition of DPSD, the effect of thermal stimuli on the transmittance gradually weakened. It was very clear that with increasing the temperature, the transmittance of MPUs showed a gradual increase owing to melting the microcrystals or destroying the ordered accumulation of hard segments. Meanwhile, the high mechanical properties were obtained, higher 15 times tensile strength and more than 100 times elastic modulus than those of pure PU as well as the excellent thermal stability. In sum, this study was of great significance for developing new functionalized PU materials. Highlights: Polyurethanes were prepared by inducing modified silicon functionality.The distinctive microphase separation evolution of MPUs was found.Thermal stimuli responses showed a gradual decrease due to different structure.High mechanical properties and thermal stability were also obtained. [ABSTRACT FROM AUTHOR]

Bismaleimide (BMI) resins is widely used in the aerospace field because of its excellent properties, but its poor toughness limits the possibility of its application in a wider range of fields. Therefore, a novel bio‐compound, 4‐(allyloxy)‐3‐methoxy‐N‐(3‐(triethoxysilyl)propyl)benzamide (AMTPM), was designed and synthesized from renewable vanillin, which has Schiff‐base structure, silico‐oxygen bond structure, and allyl structure. The chemical structure of AMTPM has been characterized and validated by Fourier transform infrared (FTIR) and hydrogen nuclear magnetic resonance (1H NMR). It was found that the addition of AMTPM can effectively promote the curing behavior of BD resins (BMI and diallyl bisphenol A (DBA) was mixed and cured at the ratio of 1:0.87, named BD resins). AMTPM can affect the thermal stability and improve the mechanical properties of BD‐AMTPM resins (BD resins modified by AMTPM in different addition), and the detailed discussion was conducted. With the increase of AMTPM content, the thermal stability of BD‐AMTPM resins was deteriorated while the residual weight percentage at 800°C (Yc) was increased. When the content of AMTPM reached 12 wt%, the results showed that Yc achieved the values at a magnitude of 37.57%. Meanwhile, the glass transition temperature (Tg) achieved 320°C. Among the BD‐AMTPM resins system, the BD‐6 wt% AMTPM has the best toughness and mechanical properties. The impact strength was increased by 29.2%, the tensile strength was increased by 22.1% and the elongation at break was increased by 44%. The fracture morphology of BD‐AMTPM resins was also studied by scanning electron microscopy (SEM) to support the mechanical experimental conclusions. This study provides a more environmentally friendly and convenient modifier, which is of great significance for expanding the application of bismaleimide resin. Highlights: A bio‐based modifying agent (AMTPM) was designed and successfully synthesized.AMTPM has both Si‐O and Schiff‐base structures.AMTPM can effectively improve the toughness of BD‐AMTPM resins through impact and tensile tests. [ABSTRACT FROM AUTHOR]

The present study aimed to characterize the functional, morphological, thermal, pasting, rheological, and antioxidant properties of flour samples from Indian browntop millet cultivars. Significant (p < 0.05) difference was observed for various chemical constituents except crude fiber content. Water absorption (2.04–2.14) and Oil absorption capacity (2.25–2.35) varied significantly among cultivars. At 90 °C, BTM4 (6.59) and BTM1 (6.29) showed the highest and lowest swelling power. The DPPH assay and TPC analysis revealed the highest scavenging activity (51.24%) and phenolic content (3.24 mg GAE/g), exhibited by BTM2. Thermal analysis revealed distinct transition temperatures with onset temperatures ranging from 27.06 °C (BTM4) to 43.11 °C (BTM1). Peak viscosity values ranged from 381 cP (BTM4) to 703 cP (BTM2), while final viscosity values ranged from 726 cP (BTM4) to 1922 cP (BTM1), respectively. Steady and dynamic rheological tests demonstrated weak-gel-like behavior in all flour samples, with storage modulus (G') exceeding loss modulus (G"). FT-IR analysis showed a broad intensity peak ranging between 3268.31 cm−1 to 3280.29 cm−1. SEM images depicted the granular microstructure, revealing spherical and irregular particles ranging from 2.34 μm to 12.4 μm across the cultivars. X-ray diffraction analysis revealed A-type crystallinity in all samples, with BTM4 exhibiting significantly higher relative crystallinity (25.54%). These findings highlight the diverse techno-functional characteristics of Indian Browntop millet flour and its potential as a valuable ingredient for enhancing various food formulations. [ABSTRACT FROM AUTHOR]

Prepregs are highly dependent on the resin, its chemical composition, and physical properties. Resin is the perishable part of prepreg materials and usually requires controlled storage, otherwise, its processability and properties may be affected. Oven curing prepregs are recognized to have longer life out of the freezer than those designed to cure in autoclave, and one of them, prepreg 2511, is the focus of this research. Prepreg 2511 has a formal out-time limit of 28 days at clean room environment (23°C/50% relative humidity), and 24 months shelf life, when frozen at −18°C, while common prepreg designed to be cured in autoclave, usually have 15 days of out-time and 12 months of shelf-life. It is known that the real shelf life and out time of epoxy-based materials tends to be longer than suppliers' recommendation. Aiming to assess 2511 performance after those 28 days of exposure to clean room ambient, during and after 24 months in freezer; the material was exposed to this environmental condition for more than 28 days and tested periodically using different methods, including, Differential Scanning Calorimeter, High-Performance Liquid Chromatography tack, among others. In resume, the goal of this research was to identify 2511 longest out life without losing its properties and which of the tests used during these experiments would be more sensitive to capture its aging. [ABSTRACT FROM AUTHOR]

Due to their great physical and mechanical behaviors, polymers have become essential in various industries. Polymers have been produced using chemical monomer synthesis, potentially dangerous non-biodegradable waste in the environment. Therefore, biopolymers are introduced, and organic compounds are found in natural sources as monomeric units. Also, biopolymers were discovered to be biodegradable and biocompatible, and these biopolymers are beneficial in numerous applications. Natural plant fibers have drawn more attention recently as potential reinforcing materials. The composites made with natural fibers have excellent mechanical and thermal characteristics. Materials made of natural fibers are inexpensive, recyclable, and environmentally beneficial. These natural fibers are excellent candidates to replace conventional fibers due to their biodegradability and eco-friendliness. The adhesion between the fibers and matrix has the most impact on the mechanical characteristics of composites. The mechanical characteristics of the composites were improved by combining chemical and physical modification techniques to increase fiber–matrix adhesion. The main objective of this study is to provide a thorough understanding of common types of biopolymers, various natural fibers, fillers, chemical treatments, and the performance of biopolymers and their composites-reinforced natural fibers. Moreover, the characterization and application of various biopolymers and composites were reviewed. [ABSTRACT FROM AUTHOR]

Highlights To improve the subpar lubricating performance of epoxy resin, this paper presents the preparation of a novel bimetallic phyllosilicate featuring a distinctive rice‐granular morphology, which incorporates nickel and iron metal cations through a facile hydrothermal process. These phyllosilicates were then integrated into the epoxy matrix to form composites. A comprehensive analysis of the target product validates the rationality of the synthesis strategy for the as‐prepared rice‐granular bimetallic nickel/iron phyllosilicate, demonstrating a homogeneous hierarchical structure with numerous tiny nanosheets of nickel/iron phyllosilicate grown in situ on the flat surfaces of the rice‐granular metal–organic frameworks. An adequate addition of nickel/iron phyllosilicates allows for excellent dispersion within the matrix and establishes strongly bonded interfaces, steadily increasing the elastic modulus and hardness. Notably, the average friction coefficients decrease from 0.515 for the pure resin to 0.450 for the composites when the filler content reaches 7%, indicating a significant solid lubrication effect. In contrast, adding just 1% nickel/iron phyllosilicate moderately improves wear resistance, elongation at break, and tensile strength. Furthermore, it was found that as the filler content increased, the weight loss rate was reduced by approximately 43.8%, while the residual char increased by 74.2%, significantly enhancing the thermal stability of epoxy composites at high temperatures. This study offers a promising approach to preparing self‐lubricated epoxy composites with favorable mechanical and thermal properties. NiFePS was successfully synthesized via a facile two‐step self‐polymerization. Excellent mechanical properties of composites could be achieved with low content of NiFePS. The friction coefficient and wear rate were lowered remarkably. The friction mechanism was solid lubrication. [ABSTRACT FROM AUTHOR]

Lattice vibrations or phonons play an important role in determining material properties, including thermal conductivity. To model the phenomenon accurately and efficiently, the most important factors governing phonon physics need to be identified, for example, polarization branches. Research continues into many aspects of the fundamental physical processes involved in phonons and into possible applications of these processes in modern physics. One of the most interesting controversies in the thermal properties of graphene involves the importance of out-of-plane acoustic phonons. The need for clarity in understanding this importance dictates that the thermal conductivity of graphene should be evaluated in various circumstances. The nanoscale heat conduction properties of graphene are studied by iteratively solving the Boltzmann transport equation and rigorously treating the normal and Umklapp collisions in the frame of three-phonon interactions. This captures the mechanistic aspects of thermal conductivity by revealing what phonon branches are present. The thermal conductivity is evaluated in different crystallite sizes and at different frequencies and temperatures. The results indicated that out-of-plane acoustic phonons become increasingly important in the frame of three-phonon interactions. The out-of-plane acoustic branch dominates thermal transport whereas the other acoustic branches make small contributions. The importance of this branch is generally attributed to the high density of states and restrictions governing anharmonic effects. The three-phonon normal and Umklapp processes must be clearly accounted for and the contribution from optical branches is not negligible at higher temperatures. The results have implications in the quest for predictive and quantitative calculations of thermal conductivity. [ABSTRACT FROM AUTHOR]

Globally, artificial wildlife structures are used widely to enhance breeding habitat or provide shelter for a host of wildlife species. They are commonly used to enhance roosting habitat for tree-dwelling bats. A remnant population of Nationally Critical long-tailed bats (Chalinolobus tuberculatus) survives in South Canterbury, New Zealand, but optimal roosting habitat is rare and breeding success low. To enhance breeding habitat, 96 Schwegler bat boxes were deployed as artificial wildlife structures in trees in regenerating indigenous forest (n = 44) and farmland (n = 52) close to known, but poor quality, maternity roosts. Schwegler boxes have similar thermal properties to high quality natural roosts. Boxes were inspected five times over 12 years. Long-tailed bats, or their signs, were detected in 10% of boxes. In addition, a new population of geckos (Woodworthia ‘Southern Alps’) was detected (occupying 26% of boxes), South Island rifleman (Acanthisitta chloris chloris) nested in 35% of boxes and a range of invertebrates was detected, but not identified, except for Canterbury tree wētā (Hemideina femorata; 40% of the boxes). Most occupancies were in regenerating forest. While boxes were unsuccessful at attracting large numbers of long-tailed bats, use by other wildlife was unforeseen, suggesting a useful tool for sampling wildlife in arboreal habitats. [ABSTRACT FROM AUTHOR]

A high‐power white laser source is prepared by using a 455 nm blue laser to excite YAG:Ce ceramics. To achieve high‐power output, a water‐cooling device is used to reduce the operating temperature of ceramics. The luminescence properties of laser‐excited phosphor ceramics are studied under different blue excitation power and different irradiation time. The experimental results show that the luminous flux of phosphor ceramics excited by the blue laser increases linearly with the increase of blue laser power, depending on the heat dissipation of the water‐cooling device. When the blue laser power increases to 73.1 W, the phosphor ceramics do not reach the luminescence saturation state. The luminous flux of phosphor ceramics excited by 73.1 W blue laser is stable within 60 min. The maximum luminous flux is 8094 lm, and the maximum working temperature of the ceramics is 110 °C. The experimental results show that water‐cooling packages are an effective means to realize high‐power white laser sources. [ABSTRACT FROM AUTHOR]

In recent years, many different biomedical implants have been created for prolonged usage within the human body. The number of these implants has been steadily expanding. It is a common practice to use metallic bioimplants as substitutes when attempting to replace human body components in an anatomically acceptable manner. But the metallic bioimplant was mostly made biocompatible by putting a biocompatible coating on its surface and then using the right surface modification techniques. This was the primary method by which the biocompatibility of the bioimplant was achieved. Thermal spraying is a method that is frequently employed in surface modification treatments to modify metallic bioimplants. These methods can be found in the medical field. This is due to the adaptability of the thermal spraying method. Because of their capacity to respond and adapt to physiochemical circumstances, coatings that are based on hydroxyapatite (HAp) are the most popular type to be used in thermal spraying. This is due to the fact that HAp is a naturally occurring mineral. On the other hand, the majority of the HAp coatings are unsuccessful as a result of the coating’s weak mechanical qualities and insufficient adhesive strength. Supplying the coating in question with reinforcement in the form of hard particles and doing so in the appropriate proportions makes it feasible to alter the qualities of HAp-based coatings to fulfill a variety of requirements. This can be accomplished by providing the coating with reinforcement. The purpose of this inquiry was to deconstruct and analyze a variety of thermally sprayed (TS) coatings. These coatings were used to adhere HAp-based coatings on bioimplants. In addition, a detailed discussion is offered on how the reinforcements have an effect on the mechanical and biocompatible qualities of the coatings. In addition, we have discussed the difficulties associated with TS HAp coatings and their potential uses in the manufacturing of 3D biomedical implants through the utilization of cold spray (CS). [ABSTRACT FROM AUTHOR]

Aim is to explore the breadmaking potential for gluten‐free goods of non‐conventional starches from Andean crops ahipa, oca, and arracacha. Their characteristics and performance in breadmaking are compared with those of cassava, taken as a reference for conventional gluten‐free root starch. Physicochemical properties of breads are studied along with the pasting and thermal properties, composition, and α‐amylase hydrolysis of starches. Arracacha starch has the lowest amylose content (2.4%) and the highest water hydration (1.4 g g−1). Its batter shows adequate proofing, but the bread is highly adhesive, with dense crumb. Ahipa starch paste has the lowest peak, trough and final viscosities determined by rapid visco analyzer, and the highest hydrolysis rate (kRVA = 2.30 min−1). Its batter exhibits, along with oca, the highest volume increase during fermentation (193–197%), but structure collapses in the oven and no alveoli are observed in the crumb. Conversely, oca forms a crumb structure similar to cassava, but with higher cell density (131 alveoli cm−2), cohesiveness (0.95), and resilience (0.65) than the latter (71 alveoli cm−2, 0.88, and 0.45, respectively). Oca starch has lower pasting temperature (64 °C) and the starch paste has similar hydrolysis rate (kRVA = 1.92 min−1) compared to cassava (71.9 °C and 2.08 min−1, respectively), making it a suitable option for providing gluten‐free yeast‐leavened breads with improved technological properties and a comparable glycemic index. [ABSTRACT FROM AUTHOR]

Highlights This study investigated the effect of multi‐walled carbon nanotubes (MWCNTs) and reclaimed gypsum of varying contents on the mechanical properties and thermal stability of polypropylene (PP) composite materials. The results indicated that the incorporation of reclaimed gypsum and MWCNTs powder into PP composites could enhance the tensile strength, impact strength, and bending modulus of PP to a certain extent. The above properties of AGY/MWCNTs/PP composites were increased by 14.6%, 131.8%, and 36.2%, respectively, with the impact properties being significantly affected. Univariate analysis of variance revealed that MWCNTs powder and recycled gypsum exerted a significant impact on the mechanical properties of polypropylene composites. Moreover, the initial weight loss temperature of AGY/MWCNTs/PP demonstrated a notable increase, from 318.71 to 398.48°C, while the maximum weight loss temperature exhibited a comparable rise, from 406.85 to 461.54°C. The impact performance and thermal stability of polypropylene composite materials have been demonstrably augmented. A synergistic effect between reclaimed gypsum and multi‐walled carbon nanotubes in the reinforcement of polypropylene composites was demonstrated. This provides a theoretical framework and practical guidance for the design and preparation of high‐performance and recyclable polymer composites. [ABSTRACT FROM AUTHOR]

Silicene has recently been revisited as a 2D material with potential thermoelectric applications. Here, the thermal properties of supported silicene are determined by optothermal Raman spectroscopy. Single and multilayer silicene is grown either directly on silver (Ag) substrates or on an intermediate tin (Sn) monolayer, introduced to reduce the influence of the substrate on the physical properties of silicene. Experimental values of an effective cross‐plane thermal conductivity of 0.5 W/mK are obtained for silicene on Ag and 0.3 W/mK for silicene on stanene‐Ag. The values of the interfacial thermal conductance, on the other hand, are 0.3 and 0.5 GW/m2K, respectively. Heterostack engineering is confirmed as a versatile strategy for extracting relevant physical parameters in silicene and for modulating the thermal response in the 2D limit. [ABSTRACT FROM AUTHOR]

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

Highlights Nowadays, non‐timber sources are of greater interest as they avoid deforestation and the pollution which occurs with cellulose obtention. An emerging alternative is using weeds such as windmill grass (Chloris spp.) to isolate cellulose since the plant grows in large quantities near crops or landfills used for farming. The present study aims to explore windmill grass as an alternative source of cellulose for applications as reinforcement in biopolymeric matrices. Treatment was conducted using the peroxyformic pulping method, varying the formic acid (FA) and hydrogen peroxide (HP) concentration to obtain an optimum cellulose extraction condition. The isolated celluloses were analyzed for chemical composition, yield, chemical functionality, crystallinity, and morphology. The optimum pulping condition (FA = 87.5%, HP = 3%) shows the gradual removal of non‐cellulosic components by microscopy. X‐ray diffraction analysis revealed a high crystallinity index (89.63%) with a characteristic cellulose type I pattern. To evaluate the reinforced effect of Chloris spp. celluloses, film formulations were made using sweet potato starch, glycerol, and cellulose at different concentrations (2.5, 5.0, and 7.5% w/w). The films' mechanical, physicochemical, and thermal properties were measured, and results indicate that adding cellulose fibers significantly improves these properties of sweet potato starch films, revealing further applications and non‐wood windmill grass added value with potential applications in the packaging sector. Windmill grass (Chloris spp.) is presented as a non‐wood source of cellulose. The peroxyformic method is reported as a less polluting cellulose extraction process. Optimal cellulose pulp presents enhanced physicochemical properties after bleaching. Cellulose‐reinforced sweet potato starch films exhibit a stable biopolymeric matrix. The films produced show enhanced water barrier and mechanical/thermal properties. [ABSTRACT FROM AUTHOR]

Carbon materials comprise a wide range of microstructures and excellent electrical and thermal properties while being cost‐effective and readily available. They can be obtained through carbothermal processes at high temperatures, starting from cellulose. Catalytically active compounds, for example, iron salts, strongly influence the carbon microstructure during the graphitization process. Different degrees of structural order can, therefore, be achieved by adjusting the concentration of the iron salts. An infusion withdrawal impregnation approach is used on filter paper to prepare a continuous gradient of the carbon microstructure. This structural change is accompanied by a continuous variation of the closely related electrical and thermal transport properties. Even more, the synergistic interplay of local sheet resistance and thermal diffusivity results in the formation of switchable temperature gradients when an external current is applied. Steady state temperature differences of up to 80 °C are observed along the centimeter‐scaled samples. The controllable temperature gradient formation will be of great interest for applications requiring a fast temperature screening. Furthermore, the temperature gradient can be imposed onto other materials, which will be particularly relevant for advanced thin film characterization applications. [ABSTRACT FROM AUTHOR]

The continuous upgrading of electronic technology has facilitated the integration and miniaturization of electronic and electrical equipment, as well as putting great pressure on the multifunctional demand for internal materials. Developing insulating materials with both low permittivity and high thermal conductivity has become imperative. This perspective focuses on polyimide (PI), which is the top material of the polymer material pyramid, discusses the characteristic parameters that affect its dielectric property and thermal conductivity. A series of basic schemes to regulate the dielectric/thermal properties of PI are summarized, revealing the bottlenecks and drawbacks of the current research. Future development trends of PIs featured low permittivity-high thermal conductivity are anticipated, and novel ideas are proposed for the development of new generation of multifunctional PIs. [ABSTRACT FROM AUTHOR]

One-dimensional negative thermal expansion material has important applications in thermal expansion control and fiber toughened composite. Orthorhombic Al1.6Sc0.4Mo3O12 nanofibers have been prepared by electrospinning. The phase composition, microstructure, morphology, and thermal expansion performance of the samples prepared at various temperatures were investigated. Results show that as-prepared Al1.6Sc0.4Mo3O12 nanofibers are smooth and homogeneous with a fiber diameter of about 370.00 nm, but they show an amorphous structure. Orthorhombic Al1.6Sc0.4Mo3O12 nanofibers can be obtained at 550 ℃ with a diameter of around 140.00 nm. With the increase of post-annealing temperatures, the crystallization of the samples was improved. However, higher post-annealing temperatures will destroy the nanofiber structure of the samples. HTXRD reveals that orthorhombic Al1.6Sc0.4Mo3O12 nanofibers show anisotropic NTE in 25–700 °C. The expansion coefficients αa, αb, and αc of Al1.6Sc0.4Mo3O12 nanofibers are −5.05 × 10–6 °C−1, 4.41 × 10–6 °C−1, and −3.18 × 10–6 °C−1, respectively. The αv is −3.83 × 10–6 °C−1, and the corresponding αl is −1.28 × 10–6 °C−1. [ABSTRACT FROM AUTHOR]

Background Results Conclusion Fried dough sticks, widely enjoyed in southeast Asia, are made by frying a mixture of wheat flour and water at high‐temperature. With the move towards industrial production, there is an increasing demand for healthier versions. Understanding the key properties of fried dough sticks and how the ingredients interact is crucial for meeting these health‐focused consumer preferences.In this study, the connections between the dough's rheological and thermal properties, alongside the interactions between gluten proteins and the oil content in fried dough sticks, were examined and analyzed at varying gliadin to glutenin mass ratios (Gli/Glu). The results indicated that a general decrease in the viscoelastic properties of the dough was associated with an increase in the Gli/Glu ratio. Furthermore, a heightened concentration of gliadin was observed to augment the mass loss of gluten proteins, thereby engendering a spatially sparse network structure. Additionally, this excessive presence of gliadin precipitated the thermal instability within the dough, necessitating an augmented chemical force to preserve the stability of the gluten network structure.At the Gli/Glu ratio of 5:5, the gluten protein exhibited enhanced thermal stability and minimal mass loss. At this specific ratio, the gluten network was characterized by a comparatively high prevalence of extended gluten films and short‐chain structures, which resulted in the production of fried dough sticks possessing minimal structural oil content. The study provided a theoretical basis for identifying the Gli/Glu ratio as an effective approach to modulate the oil content in fried dough sticks. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Halide perovskites emerge as promising candidates for thermoelectrics due to their ultralow thermal conductivity. The conventional theory based on the phonon gas model, which treats thermal transport as particle‐like behavior, shows limitations to describe the unusual thermal transport property in some halide perovskites with strong anharmonicity. Here, the significance of phonon coherence effect on thermal transport of bismuth‐halide perovskite Cs3Bi2Br9 is reported by inelastic neutron scattering and simulations including density functional theory and machine‐learning potential based molecular dynamics. This study shows that the restrictive low‐energy acoustic phonons lead to the limited particle‐like thermal conductivity, which seriously underestimates the lattice thermal conductivity of Cs3Bi2Br9. The significant contribution of wave‐like optical phonon modes, driven by the coherence effect, accounts for an additional ≈50% wave‐like thermal conductivity. Besides, the experimental weak temperature dependence of thermal conductivity along z direction (κ ≈T−0.35) is well reproduced by calculation (κ ≈T−0.37) when including phonon coherence. This work highlights the critical role of phonon coherence in Cs3Bi2Br9 and enhances understanding on the unusual thermal transport properties in halide perovskites and other related materials with strong anharmonicity. [ABSTRACT FROM AUTHOR]

While improving the thermal conductivity of composites, single‐size carbon nanotubes (CNT) often degrade their mechanical properties due to the agglomerates. To overcome this limitation, this study reported thermoplastic resin matrix composites synergistically reinforced with small, medium, and large‐size carbon nanotubes (S‐CNT, M‐CNT, and L‐CNT). Using the thermal conductivity (λ) and mechanical properties (flexural strength [F], compressive strength [C] and tensile strength [T]) as the response values, we conducted 21 sets of mixing design experiments and developed the associated quadratic term models. Further multi‐objective optimization was carried out for the above response values. Optimized multiscale CNT synergistically modified composites (S‐CNT, M‐CNT, and L‐CNT contents of 1.25, 7.02, and 2.56 wt%) exhibited a λ value of 1.168 W/mK, which was 121% higher than that of pure composite and also superior to the same content of S‐CNT‐ (1.031 W/mK), M‐CNT‐ (1.016 W/mK), and L‐CNT‐modified composites (0.983 W/mK). Additionally, the optimized composite demonstrated excellent mechanical properties (F = 1482 MPa, C = 848 MPa, and T = 1759 MPa), which were 13%, 11%, and 13% higher than those of the pure composites, respectively, and also surpassed those of the S‐CNT‐, M‐CNT‐and L‐CNT‐modified composites. Highlights: Using three different scales of carbon nanotubes modified CF/PPBESK composites.Polynomial modeling of composite's thermal conductivity and mechanical properties.Synergistic interactions between carbon nanotubes to improve the composite's thermal conductivity and mechanical properties. [ABSTRACT FROM AUTHOR]

The relationship between interfacial structure and thermal conductivity in epoxy resin/Al2O3 composite is important but is still elusive. Here, we illuminate this issue by investigating the role of four silane coupling agents in thermal conductivity for epoxy resin/Al2O3 composites. The results show that 3‐glycidoxypropyltrimethoxysilane (KH560) is the best silane coupling agent to modify Al2O3, resulting in the lowest viscosity and the highest thermal conductivity of the epoxy resin/Al2O3‐KH560 composite compared with alternative systems. This is attributed to the strong interfacial interaction between Al2O3‐KH560 and epoxy resin, as confirmed by the Fowkes model and broadband dielectric spectroscopy. The interfacial thermal resistance between the epoxy resin and Al2O3 is also quantitatively measured via a photothermal radiometry technique. The epoxy resin/Al2O3‐KH560 also has the lowest interfacial thermal resistance (1.50 ± 0.02 × 10−6 m2 K W−1), compared with the other three systems. This study advances the understanding of the relationship between interfacial structure and thermal conductivity in polymer composites. Highlights: The relationship between interfacial structure and thermal conductivity in epoxy resin/Al2O3 composite is understood.The interfacial structure is characterized by broadband dielectric spectroscopy.The interfacial thermal resistance is quantitatively measured via a photothermal radiometry technique. [ABSTRACT FROM AUTHOR]

Highlights In this electronic era, there is a demand to switch from conventional polymers to conducting biopolymers. We developed conducting biopolymer nanocomposites of cashew gum (CG) and polypyrrole (PPy) with zinc oxide (ZnO) nanofillers [CG/PPy/ZnO] via in‐situ oxidative polymerization using a sustainable solvent. These nanocomposites were characterized using Fourier‐transform infrared spectroscopy (FTIR), UV–visible spectroscopy, field emission scanning electron microscope (FE‐SEM), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The FTIR signal at 855 cm−1 confirms the successful inclusion of ZnO nanofillers into the biopolymer. UV–vis absorption of the blend nanocomposite increases with the nanoparticle doses. Among the various blend nanocomposites, the least bandgap energy was observed for 7 wt% ZnO loading. FE‐SEM revealed homogeneous dispersion of ZnO nanofillers in the CG/PPy blend at 7 wt% ZnO. TGA and DSC demonstrated that the CG/PPy/ZnO nanocomposites have better thermal stability and glass transition temperature than the pure polymer blend, indicating enhanced thermal properties. The CG/PPy/7 wt% ZnO showed the highest conductivity, 4.62 times greater than the pristine blend at 100 Hz. Dielectric constant, activation energy, AC conductivity and dielectric loss measurements demonstrated that the nanocomposites outperformed the pure polymer blend. Complex impedance analysis revealed increased impedance with rising temperature. Overall, CG/PPy/ZnO nanocomposites exhibit superior optical, morphological, thermal, electrical, and dielectric properties, making them promising for energy storage and optoelectronic applications. Ecofriendly synthesis of CG/PPy/ZnO nanocomposites Enhancement in optical, structural, and thermal properties of CG/PPy/ZnO Dielectric properties and temperature‐dependent AC conductivity are summarized. Blend nanocomposite shows higher AC conductivity and dielectric constant CG/PPy/ZnO nanocomposites are suitable for energy storage applications [ABSTRACT FROM AUTHOR]

Whey protein hydrolysates, derived from enzymatic hydrolysis of whey protein isolates or concentrates, offer enhanced bioavailability and solubility compared to intact whey protein. In this study, whey protein hydrolysates (WPHs) having different hydrolysis degrees (5%, 10%, and 15%) were produced and muffin cakes were enriched with the addition of WPHs. In general, the addition of WPHs showed a significant effect on oil and protein content while the emulsion activity was improved with the increased hydrolysis degree (HD). The degree of hydrolysis increment resulted in a significant increase in both antioxidant power and antiradical activity of the WPHs. Ferric‐reducing antioxidant power and ABTS radical scavenging activity ranged between 18.83–87.27 mg TE/100 g and 211.8–5063.1 mg TE/100 g, respectively. The highest FRAP and ABTS values were recorded for the 15% HD while the lowest was for the native whey protein isolate (WPI). The induction periods giving a clear information for the oxidative stability were 1593 min for the control muffins, and it was 1654 for the muffin added with WPI. Rheological data revealed that all cake batter samples including WPHs showed viscoelastic behavior. WPHs could be efficiently used in muffin formulation to increase the biofunctional effects of the final products. [ABSTRACT FROM AUTHOR]

Nanofluids, characterized by the dispersion of nanoparticles in a base liquid, have attracted significant attention in recent years due to their exceptional thermal properties. Specifically, the specific heat capacity of nanofluids plays a crucial role in the design and optimization of heat transfer systems. Traditional experimental methods for determining the specific heat capacity of nanofluids are often limited in terms of cost, time, and operating condition ranges. To address these limitations, this research focuses on the development of a novel predictive model for estimating the specific heat capacity of nanofluids. This study aims to develop a machine learning regression model called Gradient Boost Regression (GBR) with Grid Search optimization (GSO) for accurately predicting the specific heat capacity of aluminum nitride (Al2N3) nanoparticles that are suspended in both water and an ethylene glycol (EG) solution. The GBR-GSO model capitalizes on the strengths of GBR, which can effectively capture complex relationships, and GSO, a metaheuristic optimization technique inspired by the law of gravity. By integrating these two approaches, we aim to create a robust and accurate predictive model for specific heat capacity in nanofluids. To develop and validate the GBR-GSO model, a diverse dataset based on experimental-specific heat capacity collected from the literature has been designed. The performance of the model has been evaluated by comparing its predictions with experimental data. The GBR-GSO model achieved 99.99% accuracy with the experimental data of specific heat capacity. This research contributes to the advancement of nanofluid-based heat transfer systems by providing an effective tool for predicting the specific heat capacity of nanofluids. The developed model can facilitate the design and optimization of various engineering applications, leading to the development of energy-efficient and sustainable technologies. [ABSTRACT FROM AUTHOR]

We investigate the temperature and magnetic field-dependent electrical and thermal properties of Eu2.2Ga11Sn35, revealing a change in electronic structure and an increase in magnetoresistance with increasing field, as well as the origin of magneto-suppressed thermal conductivity of this unconventional inorganic clathrate-I material with very low cation concentration. [ABSTRACT FROM AUTHOR]

As wearable and flexible electronic devices continue to miniaturize and operate at higher frequencies, there is an urgent demand for polymer films that offer a high electromagnetic interference (EMI) shielding efficiency and effective thermal management capabilities, particularly under extreme environmental conditions. Conductive inks are extensively utilized in polymeric electromagnetic interference shielding coatings. However, the extensive utilization of organic solvents can lead to environmental pollution. Herein, we proposed a multifunctional conductive composite ink comprising waterborne polyurethane (WPU), silver nanosheets (AgNS) and heat-treated MXene, using deionized water as solvent. Inspired by the advantage of the unique "brick-mortar" layered structure, we fabricated a multifunctional flexible composite film with large size, high electrical conductivity, and good mechanical flexibility by blade coating, which has scalable manufacturing prospects for industrialization. The resultant films achieve a remarkable EMI SE of 87.3 dB at only 78 μm thickness and impressive mechanical fastness and chemical durability to various organic solvents. Meanwhile, the resultant composites also present a desirable Joule heating temperature (117 °C) and anisotropic thermal conductivity due to the compact and highly aligned morphology. In summary, our simple preparation technology and excellent comprehensive performance of composite inks have great potential in advanced thermal management and wearable electromagnetic protection devices. [ABSTRACT FROM AUTHOR]

Liner materials have extensive applications in automobile industry, packaging, and aeronautics. One of the specific uses of such materials is in thermal barrier, coating rockets, missile, and other systems used in space and defense. Each liner material exhibits different properties according to their chemical structure and composition. In this study, accelerated thermal aging of the liner material, silicone‐hollow glass microsphere composite (SHGC) has been studied along with the determination of its life span. The effect of such aging on the thermal properties of SHGC has been studied using thermogravimetry. Activation energy of the process has been determined to be in the range of 45–55 KJmol−1. The results have been compared with already reported silicon polymers. Shelf‐life of SHGC composite has also been determined using Arrhenius model. Stochastic model has been applied to determine the lower and upper limits of shelf‐life. Shelf‐life of SHGC is found to be 24 years with 28 and 18 years of upper and lower error limits. [ABSTRACT FROM AUTHOR]

In this study, graphene nanoplatelets were applied to polyester fabrics using the knife‐coating method at different concentrations (50, 100, and 150 g/kg). SEM, DSC, and TGA/DTG analyses were performed. The influence of graphene coating on hydrophobicity and surface roughness was examined by water contact angle (WCA) measurement and root mean square roughness, respectively. Abrasion resistance and tear strength tests were also performed. The effect of graphene used as a filler on the flammability of polyester fabric was evaluated for the first time according to the BS 5852 standard. No significant weight loss (only in the range of 0.4%–1.5%) was observed in the graphene‐coated samples even after 100,000 cycles. While the WCA value was 0 for the uncoated fabric, the blind coating and maximum graphene‐coated sample measured 86° and 95°, respectively. The coating process reduced the roughness of the base fabric, and the decrease continued with the increasing graphene ratio. The tear strength values that were 45.5 N in the warp and 53.6 N in the weft direction in the blind coating, increased to 52.2 and 59.1 N, respectively, at the maximum graphene concentration. Graphene coating enhanced thermal stability, increased hydrophobicity, and improved flame retardancy in the test using a smoldering cigarette. [ABSTRACT FROM AUTHOR]