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In the present work, a thermographic procedure to evaluate in-plane thermal diffusivity and parallel finite element method were applied to a metal matrix composite layer. The observed coatings were realized with copper and graphene. Graphene application is more interesting in various fields, but this innovative technology shows various issues of application like the cluster formation that reduces mechanical and physic properties of coating. In this work, the application of graphene can be made with electrodeposition, and a matrix of copper was obtained with subsequent electrodeposition processes. This innovative methodology allows to avoid the issue of cluster formation and increases the amount of graphene in the final layer. In addition, the implementation of multi-coating increases thermal diffusivity by up to 65% obtaining results difficult to reach with a single layer of graphene. In addition, a FEA simulation was carried out to observe the compliance of the numerical method aimed at predicting the thermal properties of the obtained composite. [ABSTRACT FROM AUTHOR]

The increased demand for gluten-free (GF) foods calls for the incorporation of novel ingredients to improve the technological drawbacks of GF formulations. This study aimed to evaluate the potential of a Gelidium amansii polysaccharide–based (GAP) flour as a structure-supporting ingredient in gluten-free foods in terms of its impacts on the functional, rheological, and thermomechanical properties of composite gluten-free (CGF) flours and doughs at three addition levels. The addition of GAP improved the functional properties of CGF flours and promoted starch pasting while retarding starch retrogradation during the pasting process. The steady shear and frequency sweeping tests demonstrated that GAP addition resulted in a dose-dependent increase in the apparent viscosity, G′, and G″ moduli of the dough accompanied by a slight decrease in tan (δ). Through measuring changes in the thermomechanical properties of GAP-added dough using Mixolab®, it was further confirmed that the presence of GAP increased the dough stabilization time with reductions in the consistency loss and retardation of starch re-association in the cooling phase. This study extended the application of seaweed polysaccharides to improve quality attributes of GF formulation and shed light on the use of cost-effective ingredients from algae as alternative hydrocolloids in starchy-based foods. [ABSTRACT FROM AUTHOR]

Thermal energy harvesting and its applications significantly rely on thermal energy storage (TES) materials. Critical factors include the material's ability to store and release heat with minimal temperature differences, the range of temperatures covered, and repetitive sensitivity. The short duration of heat storage limits the effectiveness of TES. Phase change materials (PCMs) are a current global research focus due to their desirable thermal properties, which improve energy performance and thermal comfort. PCMs require relatively less synthesis effort while maintaining high efficiency and enhancing cost-effectiveness. However, limited temperature range and storage capacity restrict the application of conventional PCMs. Consequently, the demand for high-energy PCM storage with enhanced thermo-physical properties is high. It is essential to explore the potential of new PCMs to improve thermal storage performance and capacity while reducing energy consumption. This review article explores the classifications and applications of PCMs, addresses the challenges in enhancing their thermo-physical properties, and outlines the selection criteria for high-heat storage applications. Additionally, it provides an in-depth analysis of recent research and developments related to PCMs. [ABSTRACT FROM AUTHOR]

This research explores sustainable usage of waste fabric, specifically knitted three-thread polyester fleece fabric (3-TPEF), to reinforce epoxy. Different orientations of the fabric (wale and course), varying weight proportions, and fibers derived from the fabric are studied. The impact of unmodified and epoxy-functionalized glass microspheres (UGM and FGM) on the mechanical and thermo-mechanical properties of composites is investigated. Custom-made mold was utilized to regulate fabric weight, reduce air traps, and collect surplus resin released during compression. Compared to neat epoxy, FGM-incorporated fabric-reinforced composites exhibit increased tensile strength (43 vs. 51 MPa), tensile modulus (2.2 vs. 3.5 GPa), flexural strength (83 vs. 98 MPa), flexural modulus (2.9 vs. 4.3 GPa), and impact strength (20 vs. 26 kJ/m2). Weight loss during decomposition decreased from 76.9% (neat epoxy) to 57.7% (composite), indicating improved thermal stability. Dynamic mechanical analysis shows a 1.5-fold increase in relative loss modulus area and tan-δ area, highlighting the improved damping and energy-dissipation capabilities. Moldability and formability involved in the fabrication were demonstrated by manufacturing brake levers and decorative wall panels using 3D-printed mold and wire mesh. The enhanced performance of composites fabricated through this sustainable circular economy approach makes them suitable for automotive and construction applications. [ABSTRACT FROM AUTHOR]

This study investigates the mechanical, thermal, and water absorption properties of high-density polyethylene (HDPE) composites filled with barley straw and varying amounts of waste rubber. The research aims to develop sustainable materials that repurpose agricultural and industrial waste while addressing resource scarcity and waste management challenges. Composites were prepared using a twin-rotor mixer and hydraulic press, with waste rubber content varying from 0 to 20 wt%. Mechanical properties were evaluated through tensile testing, thermal behavior was analyzed using TGA, DTG, and DSC, and long-term water absorption was measured. Results show that increasing waste rubber content from 0 to 20% led to a decrease in tensile strength (11.3 to 8.9 MPa) and tensile modulus (1760 to 790 MPa), while relative extension increased (2.4–5.9%). Thermal analysis revealed a slight reduction in onset degradation temperature (270 °C to 240 °C) and increased char residue (8–18%) with higher rubber content. Water absorption decreased significantly, from 12 to 13% to 6–7% after 600 h of immersion, as waste rubber content increased. These findings demonstrate that incorporating waste rubber into HDPE/barley straw composites results in materials with enhanced flexibility and water resistance at the cost of some strength and stiffness. In conclusion, the results of this study offer a clear pathway for the development of sustainable polymer composites that have broad potential applications across industries like construction, marine infrastructure, automotive, and packaging. By replacing traditional, resource-intensive materials with eco-friendly alternatives, these composites not only provide functional benefits but also support global efforts toward sustainable development and environmental conservation. [ABSTRACT FROM AUTHOR]

Investigating how the thermal transport properties of iron change under extremely high pressure and temperature conditions, such as those found in the Earth's core, is a major experimental challenge. Over the past decade, there has been a great deal of discussion and debate surrounding the thermal conductivity of the iron-based Earth's core and its thermal evolution. One reason for this may be the variability in the experimentally obtained thermal conductivity of iron at high pressures and temperatures. In this study, we present the experimental results of measuring the thermal conductivity of hexagonal-closed-pack (hcp) iron over a wide pressure-temperature range up to 176 GPa and 2900 K using the pulsed light heating thermoreflectance technique in a laser-heated diamond anvil cell. Our findings indicate that the temperature derivative of the thermal conductivity of hcp iron undergoes a change from negative to positive above 74 GPa, potentially making hcp iron highly conductive at conditions similar to those observed in the Earth's core. This observation represents a notable example of a phenomenon where pressure appears to influence the sign of the temperature derivative of the thermal conductivity of an isostructural metal. [ABSTRACT FROM AUTHOR]

This study presents a thorough examination of the structural and thermal characteristics of Bi12SiO20 crystal. X-ray diffraction (XRD) analysis was employed to investigate the crystallographic structure, while scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) were utilized to ascertain morphological features and elemental composition, respectively. The XRD spectrum exhibited numerous peaks corresponding to the cubic crystalline structure. Thermal behavior was investigated through thermal gravimetric analysis (TGA), differential thermal analysis (DTA) and differential scanning calorimetry (DSC). Within the crystal, negligible weight loss was observed up to 750 °C, followed by weight loss processes occurring in the temperature ranges of 750–919 °C and above 919 °C. The 2% weight loss in the range of 750–919 °C was associated with the decomposition process, and the activation energy of this process was found to be 199 kJ/mol considering Coats-Redfern expression. A significant weight loss was observed in the region above 919 oC and was associated with the decomposition of the Bi12SiO20 compound and/or the melting processes of the components of the Bi12SiO20 compound. Three endothermic peaks were observed in the DTA plot. Additionally, DSC measurements conducted under varied heating rates indicated endothermic crystallization process around 348 °C, with an activation energy of 522 kJ/mol determined through the Kissenger equation. These findings present valuable details regarding the crystal's structural configuration, morphological attributes, and decomposition/phase transitions, thereby illuminating its potential applications across various fields. [ABSTRACT FROM AUTHOR]

Improvement of thermal conductivity of polymer present a key to realizing efficient thermal transport used for various applications remains a long-standing challenge. In fact, we investigate the effect of TBPO-capped CdSe nanoparticles concentration on Thermal properties in Poly (3-hexylthiophene) (P3HT) thin films. We employed photothermal deflection technique PTD for thermal conductivity and diffusivity determination. Thermal conductivity and diffusivity were determined by fitting theoretical amplitude and phase of PTD signal to the experimental ones. We remark that thermal diffusivity D decreased for 3.52– 0.23 m2/s as function of CdSe nanoparticles concentration (NPs) in P3HT. However, thermal conductivity K increases for 1.78– 3.18 W/m.K as respect of CdSe nanoparticles concentration in P3HT. High thermal conductivity and lower thermal diffusivity are obtained for 40% TBPO-capped CdSe concentration in P3HT sample. [ABSTRACT FROM AUTHOR]

Thermal properties of thorium nuclear fuels are influenced by the shape and size distribution of thorium oxide particles. The production of thorium oxide is significantly influenced by the size and shape of the thorium oxalate particles which are typically formed during precipitation process. This study investigated the synthesis of these particles in a micro-reactor system. In summary, the findings showed that at high concentrations of oxalic acid, increasing the total flow rate to a certain extent leads to a decrease in the size of the particles. Also, it was found increasing the reaction temperature leads to larger particles. [ABSTRACT FROM AUTHOR]

Vitrimers have emerged as a prominent research area in the field of polymer materials. Most of the studies have focused on synthesizing polymers with versatile dynamic crosslinking structures, while the impact of chemical structure on aggregate structure of vitrimers, particularly during polymer processing, remains insufficiently investigated. The present study employed commercial maleic anhydride-grafted-high density polyethylene (M-g-HDPE) as the matrix and hexanediol as the crosslinker to facilely obtain fiber-shaped HDPE vitrimers through a reaction extrusion and post-drawing process. Through chemical structure characterization, morphology observation, thermal and mechanical properties investigation, as well as aggregate structure analysis, this work revealed the influence of dynamic bonds on the formation of aggregate structures during fiber-shaped vitrimers processing. A small amount of dynamic bonds in HDPE restricts the motion of PE chain during melt-extruding and post-drawing, resulting in a lower orientation of the PE chains. However, lamellar growth and fibril formation during post-drawing at high temperature are enhanced to some extent due to the competition between dynamic bond and chain relaxation. The uneven morphology of fiber-shaped HDPE vitrimers can be attributed to the stronger elastic effect brought by dynamic bonding, which plays a more dominant role in determining the mechanical properties of fiber-shaped vitrimers compared to aggregate structure. [ABSTRACT FROM AUTHOR]

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

In this study, the lavender essential oil-incorporated polylactic acid (PLA) nanofibers were fabricated by the electrospinning technique with the presence of kolliphor as a nonionic surfactant. The FTIR spectra supported the chemical composition of the fibers. The FTIR spectra demonstrated that there is no chemical reaction present between PLA and lavender essential oil. The SEM images of all nanofibers showed bead-free morphology. ImageJ results showed that the average diameter of lavender oil-loaded fibers ranged between 121.6 ± 32 and 228.2 ± 53 nm. All lavender essential oil-incorporated nanofibers were hydrophobic with satisfactory thermal properties. Furthermore, the lavender essential oil-incorporated PLA nanofibrous mats exhibited good antioxidant activity. The results showed that as the concentration of the essential oil in resulting nanofibers increased, the antioxidant activity also increased. According to the results of this study, lavender essential oil-loaded PLA fibers can be considered for a wide range of potential applications such as active packaging, food coating, facial masks, and wound dressing. [ABSTRACT FROM AUTHOR]

This study investigates the synthesis and characterization of new diamines with carbazole and imidazole pendant groups, leading to the development of polyamides and polyimides. The polyamides were synthesized by reacting diamines with carboxylic acids using polyamidation and phosphorylation techniques, while polyimides were prepared by combining diamines and dianhydrides. FT–IR and 1H-NMR analyses were used for comprehensive structural elucidation of diamine, polyamides, and polyimides. The polyamides and polyimides with inherent viscosities ranging from 0.48 to 0.64 dL/g showed notable thermal stability. The T10% weight loss values were between 287 and 340 °C for polyamides and 321–381 °C for polyimides. The percentage of char residue varied between 33 and 56% at 700 °C. Additionally, the maximum emission wavelengths of polymers ranged from 410 to 436 nm. The presence of bulky carbazole and imidazole pendant groups facilitated the good solubility of the polymers in common organic solvents. The antibacterial properties of synthesized polyamides and polyimides against both Gram-negative and Gram-positive bacteria and fungi were investigated. [ABSTRACT FROM AUTHOR]

In this work, 24CrNiMo alloy steel specimens were successfully prepared using laser direct metal deposition (LMD). The relationships between their microstructure, residual stress, as well as their thermal fatigue and wear properties for different types of treatments were then investigated. The treatments included quenching and tempering (QT), and stress relief annealing (SR) of the prepared samples. The study provided clear evidence that grain refinement was achieved after the QT and SR treatments. The hardness for the as-deposited specimens was found to be 325-380 HV0.2, while for the samples obtained after the QT and SR treatments, their values were obtained to be about 390 HV0.2 and 355 HV0.2, respectively. In comparison to the as-deposited samples, the QT treated specimens were reduced from a larger tensile stress of 176 ± 96 MPa to − 14 ± 5 MPa, while the SR specimens were reduced from 176 ± 96 MPa to − 44 ± 10 MPa. The microstructure and residual stress transformation resulted in improved wear resistance and thermal fatigue properties of the specimens, where the wear weights of the as-deposited specimens were about 13 and 3.7 times higher than that for the QT and SR processed specimens. Overall, a significant improvement in the mechanical properties of the QT treated specimens was achieved. [ABSTRACT FROM AUTHOR]

The increasing demand for high-performance materials has led to the development of natural fiber composites as an alternative to synthetic fiber composites. However, the low thermal conductivity of natural fibers limits their use in advanced applications. In this study, we have developed polyaniline-coated natural fiber composites to enhance their thermal properties. The methodology of this study involves the preparation of natural fiber composites using polyaniline-coated natural fibers as a reinforcement and a bio-based resin as a matrix. The composites were then coated with polyaniline, which was synthesized through chemical oxidation of aniline monomer. The coated composites were characterized using various analytical techniques such as Fourier-transform infrared spectroscopy, scanning electron microscopy, and thermogravimetric analysis to evaluate their structural, morphological, and thermal properties. The materials used in this study were natural fibers, bio-based resin, aniline monomer, ammonium persulfate, and hydrochloric acid. The gap identification of this study is the low thermal conductivity of natural fiber composites, which limits their application in advanced fields such as aerospace, automotive, and electronics. The problem identification is the lack of a cost-effective and eco-friendly method to enhance the thermal properties of natural fiber composites. The results of this study showed that the polyaniline-coated natural fiber composites exhibited enhanced thermal conductivity compared to the uncoated composites. The improvement in the properties of the composites was attributed to the high conductivity of polyaniline and its ability to form a continuous conductive network throughout the composite matrix. The development of polyaniline-coated natural fiber composites provides a cost-effective and eco-friendly approach to enhance the thermal properties of natural fiber composites. This approach has the potential to expand the use of natural fiber composites in advanced applications, leading to a sustainable and greener future. [ABSTRACT FROM AUTHOR]

This paper investigates the production of hydrothermal responsive shape memory filaments with different draw ratios (0.8, 2.0 and 3.2) using microcrystalline cellulose (MCC) as a filler and shape memory polyurethane (SMPU) as a matrix. A mechanical-thermo-aqueous programming test was conducted to study the shape-memory properties of the microcomposite filaments. The effect of draw ratio and triggering temperature on mechanical, physical, thermal, morphological, and shape memory properties was thoroughly studied. Among the microcomposite filaments, SMPU-MCC with a draw ratio of 2.0 exhibited the highest tenacity value of 0.91 cN/dtex in its original shape with an elongation of 385.2%. The differential scanning calorimetry results showed that the glass transition temperature (Tg) of the filaments increased as the draw ratio increased from 0.8 to 3.2, ranging from 38.35 to 41.02 °C. The crystallinity percentages obtained for pure SMPU, SMPU-MCC-0.8, SMPU-MCC-2.0, and SMPU-MCC-3.2 were 27.10%, 30.68%, 38.72%, and 36.88%, respectively. In addition, an optimum draw ratio led to a degradation temperature rise from 372.5 to 391.3 °C which shows the thermal stability of the filaments was significantly influenced by the intermolecular bonding between MCC and SMPU, which intensified as the draw ratio increased from 0.8 to 2.0. Moreover, the filaments exhibited excellent mechanical and thermal properties in six cycles at the optimum draw ratio and triggering temperature indicating their future application for repeated use without experiencing major changes in shape memory properties. [ABSTRACT FROM AUTHOR]

The hydrophilic property of lignocellulosic fibers is the main obstacle to improve the performance of structural bio-composites. To effectively utilize such fibers in high-performance composites, their hydrophobicity must be significantly increased. This study presents the hydrophobicity enhancement of okra woven fabric (OWF) by the application of hydrophobic nano-fumed silica (NFS) coating. Different concentrations of NFS were investigated, and SEM analysis confirmed that 1% NFS coated OWF presented the greatest quantity of nanoparticle deposition. The 1% NFS treated OWF exhibited the highest water contact angle of 137.2 ± 1° (~ 148% increased than uncoated fabric) and the greatest tensile strength of 21.85 ± 1.64 MPa in the warp direction and 15.66 ± 1.73 MPa in the weft direction (~ 46.35% and ~ 42.75% respectively superior to uncoated one). The TGA analysis demonstrated that the thermal characteristics have also been enhanced by NFS coating. The interaction between NFS and OWF has been investigated using FTIR analysis, while their elemental composition has been assessed using EDX and XPS techniques. [ABSTRACT FROM AUTHOR]

The effect of different concentrations of fly ash aluminosilicate cenospheres on the structure and properties of elastomeric composites is studied. Composite materials based on ethylene–propylene–diene rubber (EPDM-40) with different mass fractions of fly ash (10, 20, 30%) are obtained using laboratory rollers. The microstructure of mixtures of EPDM and aluminosilicate cenospheres is studied by optical microscopy. It is shown that the concentration of the filler of more than 30 wt % increases the concentration of larger cenosphere agglomerates in the structure, which indicates interfacial separation in the mixtures, which is probably associated with the fact that mechanical mixing on mixing equipment does not make it possible to achieve uniform distribution of the filler throughout the elastomeric matrix. The appearance of new absorption bands in the region of 1400–800 cm–1 that correspond to the stretching vibrations of Si–O–Si present in aluminosilicate cenospheres is detected in the IR spectra. According to the thermogravimetry data of the compositions under study, the introduction of aluminosilicate cenospheres promotes a slight increase in the thermal stability of the composition under study with the concentration of cenospheres of more than 30%. The influence of the concentration of aluminosilicate cenospheres on the resistance of the composites to aggressive media is analyzed, and it is found that the introduction of a cenosphere filler in the amount of 10 to 30 wt % into mixtures based on EPDM can increase the oil and petrol resistance of the materials. [ABSTRACT FROM AUTHOR]

In this study, resveratrol was substituted for phenol in different molar ratios (4%, 8%, 12%, 16% and 20%) with lignin, phenol and formaldehyde as raw materials, and a new resveratrol modified lignin-based phenolic resin (R-LPF) with high glass transition temperature (Tg) and improved mechanical properties was synthesized. The curing behaviors of phenolic resin (PF), lignin phenolic resin (LPF) and R-LPF were investigated. The thermal mechanical properties, thermal stability, comprehensive mechanical properties, frictional properties and morphology were systematically tested and analyzed. The results show that the highest Tg of the modified R-LPF reaches 346.2 °C. The Ts reaches 231.5 °C, and the residual carbon rate reaches 66.2% at 800 °C. For 12% substitution ratio, the maximum tensile strength, bending strength and impact strength are respective 28.72 ± 1.10 MPa, 57.58 ± 1.95 MPa and 3.14 ± 0.19 KJ/m2. Compared with PF and LPF, the tensile strength of R-LPF is increased by 21.5% and 40.4%, and the bending strength is increased by 6.5% and 30.4%, while the impact strength is increased by 38.9% and 58.6%, respectively. The wear resistance is also significantly improved. The modified R-LPF structure has good rigidity, high crosslinking density, excellent mechanical and thermal properties, and it makes up for the defects of system performance decline caused by the introduction of lignin and provides a direction for the development of green high-performance phenolic resin. [ABSTRACT FROM AUTHOR]

Natural fibers and nanomaterials are currently receiving more attention in the construction sector for two reasons. One reason is to use natural fibers instead of synthetic ones in fiber-reinforced concrete to create environmentally friendly products. In this study, sisal fiber (SF) and Cloisite 30B nanoclay particles were used to manufacture cement nano concrete. The cement nano concrete was reinforced with 3 wt% 10 mm sisal fiber and varying levels of Cloisite 30B nanoclay (0%, 0.5%, 1%, 1.5%, and 2%). Comprehensive research was conducted to evaluate the physical, mechanical, thermal, and water absorption properties of the concrete. The results indicate that the incorporation of nanoclay enhances these qualities. The results of the experiments indicated above demonstrate that the 3 wt% SF and 1.5% nanoclay concrete has superior mechanical qualities to other nanoclay concrete in terms of compressive strength (7.12 MPa) and flexural strength (9.6 MPa). Additionally, testing was performed on the concrete's morphology, physical properties, and water absorption. [ABSTRACT FROM AUTHOR]

This work aims to convert the bio-waste material into a fruitful product. This prepared product can be a solution for environmentally hazardous materials like polymer bags and plastic food wrappers. The prepared material is composed of bio-waste pomegranate peel powder and environmentally friendly polyvinyl alcohol. To extend its functionality in food wrappers, the silver nitrate solution is incorporated. The prepared samples were undergone various performance studies. The prepared films show high thermal with standing capacity and tensile properties and especially show better results in biodegradability as well as antibacterial activity. Among the fabricated films, the 5 mM AgNO3-fabricated film shows that the thermal stability up to 331 °C also possesses higher tensile strength of 25.7 MPa. These results make the possibilities of the fabricated PP/PVA/5 mM AgNPs film as an alternative for conventionally used plastic-based food wrappers. [ABSTRACT FROM AUTHOR]

In this research study, the synthesis of poly lactic acid (PLA) based bio composite material factors contributions were investigated through the Taguchi-based grey relational analysis (GRA) technique. Effects of micro crystalline cellulose (MCC) and montmorillonite (MTT) nano clay filler, sorbitol (S) plasticizer, and temperature (T) operating factor on the PLA matrix through melt-mixing preparation method. The tensile strength (TS), Young modulus (YM), flexural strength (FS), flexural modulus (FM), hardness, impact strength (IS), water absorption (WA), and density properties of bio composite material were investigated for each experimental setup (orthogonal array, L16). Additionally, neat PLA and optimal sample structural, thermal, and morphological properties were examined through Fourier transform infrared spectroscopy (FTIR), X-Ray diffraction (X-RD), thermal gravimetry analysis/differential thermal gravimetry (TGA/DTG), and DSC and SEM analyses. The obtained result for optimal mechanical and physical properties of MCC/MTT/S/PLA bio composite was MCC at level 3 (6%), MTT at level 4 (9%), S at level 2 (10%), and T at level 4 (175 °C). Analysis of variance (ANOVA) shows that MTT has the greatest significant effect on mechanical and physical properties of MCC/MTT/S/PLA bio composite followed by MCC, T, and S. The confirmation test indicates that the improvement of weighted grey relational grade (GRG) from 0.7896 to 0.846 and the FTIR, XRD, thermal gravimetry/differential scanning calorimetry (TG/DSC), and scanning electron microscopy (SEM) results indicates that the good interaction between PLA and fillers, improvement of thermal and morphological properties of optimal (6MCC/9MTT/10S/175 °C) bio composite samples. Therefore, the multi-response characteristics of MCC/MTT/S/PLA bio composite can be highly improved by this technique. [ABSTRACT FROM AUTHOR]

There is an increasing demand for bio-based chitosan materials doped with synthetic polymers for sustainable production and economic development. Due to their helpful medical applications, chitosan-based nanocomposites containing ZnO nanoparticles (NPs) are very interesting. In the present study, new composite materials containing newly synthesized methacrylate-based polymer Poly(2-{[(2,4-chlorophenyl)methyl]amino}-2-oxoethyl-2-methylprop-2-enoate (PDCBMA), chitosan (CS) and biosynthesized ZnO NPs were produced by hydrothermal method. The composites were characterized by FTIR, XRD, SEM, EDX, and TEM. Synthetic PDCBMA blended with CS decreased the thermal stability of pure CS, but the addition of ZnO NPs slightly increased the thermal stability. Blending with PDCBMA and adding ZnO NPs increased the glass transition temperature (Tg) of pure CS. While the antibacterial activities of PDCBMA-CS/ZnO nanocomposites were significantly increased compared to CS, the antifungal effect was low. It was determined that ZnO NPs and PDCBMA included in the structure of CS were anticarcinogenic on A549 cells even at the lowest concentration (16 µg/mL). It was determined that the wound-healing effect of the PDCBMA-CS mixture was better than that of the control group, and the nanocomposite containing 3% ZnO NPs had a wound-healing activity close to the control group. The antimicrobial activity of the nanocomposite containing PDCBMA-CS blend and 3% ZnO NPs is higher than CS, so it is considered a good alternative as a substitute wound-healing material. [ABSTRACT FROM AUTHOR]

This work explored whether partial cellulose bioconversion with fungal mycelium can improve the properties of cellulose fibre-based materials. We demonstrate an efficient approach for producing cellulose-mycelium composites utilizing several cellulosic matrices and show that these materials can match fossil-derived polymeric foams on water contact angle, compression strength, thermal conductivity, and exhibit selective antimicrobial properties. Fossil-based polymeric foams commonly used for these applications are highly carbon positive, persist in soils and water, and are challenging to recycle. Bio-based alternatives to synthetic polymers could reduce GHG emissions, store carbon, and decrease plastic pollution. We explored several fungal species for the biofabrication of three kinds of cellulosic-mycelium composites and characterized the resulting materials for density, microstructure, compression strength, thermal conductivity, water contact angle, and antimicrobial properties. Foamed mycelium-cellulose samples had low densities (0.058 – 0.077 g/cm3), low thermal conductivity (0.03 – 0.06 W/m∙K at + 10 °C), and high water contact angle (118 – 140°). The recovery from compression of all samples was not affected by the mycelium addition and varied between 70 and 85%. In addition, an antiviral property against active MS-2 viruses was observed. These findings show that the biofabrication process using mycelium can provide water repellency and antiviral properties to cellulose foam materials while retaining their low density and good thermal insulation properties. [ABSTRACT FROM AUTHOR]

A structural adhesive series of biomass-based polyurethane (Biomass-PU) is synthesized using polypropylene glycol (PPG2000), isosorbide-based polyol (RPO300) as polyols, isophorone diisocyanate (IPDI) as an isocyanate and 4-tert-butylphenol (BP) as a capping agent. Three different equivalent ratios of PPG2000/RPO300, 9/1 (Biomass-PU1), 7/3 (Biomass-PU2), and 1/1 (Biomass-PU3), are evaluated to determine the effect of isosorbide-based polyol content on the properties and the optimizing formulation of biomass-PU structure adhesive. The 9/1 ratio of PPG2000/RPO300 substantially leads to the improvement of impact strength by up to 35 MPa, and the PPG2000/RPO300 = 9/1 ratio exhibits better thermal properties and impact strength than those of other ratios. To achieve more compatibility between biomass-PU structure adhesive and core–shell rubber (CSR) toughener, novel CSRs are successfully synthesized using acryl-PU as a shell and biomass-based PU as a core. The chemical structure of biomass-PU structure adhesives is analyzed through FT-IR Spectroscopy and NCO% titration. Thermal properties are evaluated using TGA and DSC analysis. Their molecular weights are measured by GPC. Also, the core–shell rubber (CSR) with a polyurethane shell is prepared to reinforce the impact strength of Biomass-PU structure adhesive. [ABSTRACT FROM AUTHOR]

In this study, a technique to estimate the thermal properties of a suspended copper wire using the 3ω method was proposed and its operation was demonstrated. This approach used a digital multimeter with a large measurement buffer to implement a procedure in which an appropriate window function and a discrete Fourier transform (DFT) were applied. This significantly reduces the noise level to a few nV, especially in the lower-frequency regions (less than 1 Hz), even if a longer measurement time is required. The third-harmonic voltage signal containing the thermal properties information for the 3ω method was clearly observed with a high signal-to-noise (S/N) ratio, and the thermal conductivity and diffusivity were estimated from 60 K to 300 K from the current frequency dependence of the third-harmonic voltage. The thermal conductivities of the copper wire were determined to be 423.0 and 385.9 W/mK at 100 and 300 K, respectively. Specific heat was calculated from thermal conductivity and diffusivity, and the Debye temperature was estimated to be 346 K from the temperature dependence of the specific heat. These values were in good agreement with previous research. Measurement of thermal properties using a digital lock-in amplifier with identical configuration resulted in overestimation of thermal conductivity in entire temperature regions owing to a low S/N ratio throughout the analysis of the DFT. The technique based on DFT with a window function is therefore more reliable for detecting the third-harmonic voltage in the low-frequency region of less than 1 Hz because it obtains a high S/N ratio. [ABSTRACT FROM AUTHOR]

The thermal and nonlinear optical (NLO) properties of alizaringelb R solution are investigated experimentally and numerically. The thermal conductivity, K, of alizaringelb R solution is calculated by constructing a device and found to decrease with the increase in absolute temperature. The change in refractive index, Δ n, of alizaringleb R solution and its nonlinear index of refraction (NLIR), n2, are estimated via diffraction patterns (DPs) under irradiation with a 473 nm cw laser beam. As high as 4.73 × 10–3 and 4.81 × 10–11 m2/W of Δ n and n2 are determined. The collapse of DPs phenomenon through the deformation of the resulted DPs seen to occur. The resulted DPs are numerically calculated via the use of a mathematical model that is solved using the diffraction integral. [ABSTRACT FROM AUTHOR]

The red-emitting material SrBaMoO4:0.16Eu3+ was synthesized by using a high-temperature solid-state method. X-ray diffraction (XRD) and fluorescence spectroscopy were employed to analyze the crystal structure and luminescent properties. The results revealed that the sintering temperature had an influence on the crystal structure of the samples, with an optimal sintering temperature of 800℃. SrBaMoO4:0.16Eu3+ synthesized at 800℃ for 6.5 h exhibited a pure crystalline phase of SrBaMoO4. The luminescent intensity of the SrBaMoO4:0.16Eu3+ sample under excitation at 394 nm was tested at different temperatures. When the temperature reached 100℃, the luminescent intensity was 72.11% of the initial intensity, and the temperature reached 175℃, it dropped to 35.27% of the initial intensity. The sample demonstrated efficient excitation by blue light (464 nm), resulting the emission peak at 615 nm corresponding to the 5D0-7F2 transition of Eu3+. The luminescent intensity of the sample was found to increase with increasing Ba2+ concentration, reaching its maximum intensity when the Ba2+ doping concentration x was 0.27, followed by a gradual decreaseat excessive doping concentration, indicating concentration quenching. The CIE coordinates were calculated for the sample under excitation at 464 nm, revealing exhibited the best red emission at the Ba2+ doping concentration of x = 0.27. Additionally, first-principles calculations were used to determine the band structure and density of states of the sample. [ABSTRACT FROM AUTHOR]

Context: This work introduces a method for generating generalized structures of amorphous polymers using simulated polymerization and molecular dynamics equilibration, with a particular focus on amorphous polymers. The techniques and algorithms used in this method are described in the main text, and example input scripts are provided for the GMXPolymer code, which is based on the GROMACS molecular dynamics package. To demonstrate the efficacy of our method, we apply it to different glassy polymers exhibiting varying degrees of functionality, polarity, and rigidity. The reliability of the method is validated by comparing simulation results with experimental data in various structural and thermal properties, both of which show excellent agreement. Methods: This work implements the GMXPolymer simulated polymerization algorithm on the GROMACS program. GMXPolymer code controls the main polymerization loop. The energy minimizations and molecular dynamics simulations use the GROMACS program called by the GMXPolymer code. A new ITP file is generated when a new bond is formed, and the necessary additions to the ITP file are made to include new bonds, angles, and dihedrals. In preparing the ITP file of the monomer, the charge of the reactive atom must be modified before the code runs so that it is a correct value after bonding. [ABSTRACT FROM AUTHOR]

The study primarily focuses on the in situ synthesis of polystyrene (PS) and copper oxide (CuO) nanocomposites. An extensive analysis was conducted on the optical, thermal, mechanical, and electrical properties of PS with different CuO concentrations. The effective inclusion of CuO into PS was characterized by Fourier-transform infrared spectroscopy (FTIR), UV–visible spectroscopy, filed emission scanning electron microscopy (FE-SEM), X-ray diffractometry (XRD), differential scanning calorimetric analysis (DSC) and thermal gravimetric analysis (TGA). The reinforcement of CuO into the PS was established through FTIR. The optical bandgap energy deduced from UV–visible spectra decreases with CuO addition, whereas the refractive index rises significantly with the addition of CuO nanoparticles up to 7 mass%. The XRD analysis revealed the amorphous to crystalline transformation of PS with the homogeneous dispersion of nanoparticles. The SEM–EDX analysis revealed the uniform distribution of CuO nanofillers in the PS matrix. The CuO addition considerably increased the glass transition temperature and thermal stability of PS. The tensile strength, impact resistance and hardness of nanocomposite were significantly increased with the loading of CuO in the polymer matrix. The AC conductivity and dielectric constant of the PS was improved with the addition of CuO nanoparticles. The effect of temperature on conductivity, activation energy, and pre-exponential factor was determined using the universal power law and the Arrhenius equation. The highest electrical and mechanical properties were observed for 7 mass% nanocomposite. The synthesized PS/CuO nanocomposites with excellent optical characteristics, thermal stability, electrical conductivity, dielectric constant and mechanical strength can be used in supercapacitors and flexible nano-electronic devices. [ABSTRACT FROM AUTHOR]

The researchers attract nanofluids due to their improved thermal and physical properties compared to the base fluid. The colloidal mixture of nanometre-sized particles with conventional fluid is known as nanofluids. Compared with single nanofluids, hybrid nanofluids show better enhancement in thermophysical properties. Combining nanoparticles into the host fluid is called a hybrid nanofluid. The preparation of nanofluid needs more importance. However, the physiochemical properties of the nanofluid mainly depend on the stability of the nanofluid. The article aims to provide detailed information about preparing different types of single and hybrid nanofluids dispersed in various base fluids, preparation techniques, stabilization processes, applications and challenges. Different types of surfactants and characterization methods are suggested to improve the stability of the prepared solution. It was observed that all types of nanoparticles and hybrid nanoparticles could be synthesized with different base fluids with the help of the sonication process, particle-to-surfactant ratio, magnetic stirrer and many more. The two-step method is mostly preferred by the researchers compared to the single-step method to prepare the nanofluid. Application of single and hybrid nanofluids has been highlighted in different areas; few challenges have also been identified and must be checked before implementation in the industry. [ABSTRACT FROM AUTHOR]

In this study, Ni20Ti50Sn30 (atomic %) sample was prepared using the arc melting method. Some thermodynamic parameters (phase transformation temperatures, PTT; enthalpy, ΔH; and phase transformation hysteresis, H) obtained from the phase transformations of the alloy were determined using differential scanning calorimetry (DSC). The sample exhibited high-temperature shape memory alloy (HTSMA) properties. X-ray (XRD) analysis was performed to determine the crystal structure properties at the alloy. The presence of B2, B19′, Ti2Ni, β-Ti, Ni3Sn4, TiNiSn and Ti3Sn phases was identified through X-ray analysis of the alloy. Scanning electron microscopy (SEM) was used to examine the pre- and post-corrosion surface morphologies of the sample, with EDX analysis being performed to reveal chemical structure determinations (matrix phases, precipitates and weathering zones). The presence of dendritic arms was observed, while martensite plates were absent in all SEM images. Particularly in the SEM image taken after corrosion, it was noted that the TiO2 layer placed on the surface of the matrix rich in Ti elements altered the surface morphology of the alloy. The presence of Ti and O elements in the post-corrosion EDX analysis confirmed the existence of this layer. Biocompatibility studies of the alloy were conducted using potentiodynamic corrosion tests and electrochemical impedance spectroscopy (EIS) methods. It was determined that the NiTiSn sample was in the excellent stability class according to corrosion standards. [ABSTRACT FROM AUTHOR]

Manufacturing of several products with better quality and features in industries depends upon the cooling processes. Based on the thermal properties, this research aims to investigate the effect of dissipative heat in non-Newtonian Jeffrey nanofluid flow along horizontal channels embedded in a porous matrix. Due to cross-diffusion, the time-dependent electrically conducting fluid presents the role of Brownian motion and thermophoresis. Further, the conjunction of binary chemical reactions encourages the flow phenomena. The appropriate choice of the similarity variables helps to transform a dimensional system of the governing equations into their non-dimensional form. Further, the shooting-based Runge–Kuta–Fehlberg method is used to solve the transformed governing equations. The structural behaviour of the characterising constraints is presented via graphs and described briefly. The validation with the earlier result is presented in a particular case showing a good correlation. [ABSTRACT FROM AUTHOR]

Electro-discharge machining (EDM) has been extensively employed for machining hard alloys, and its simulations have been widely conducted using finite element analysis (FEA). However, the majority of mesh-based models depended on forecasting the crater profile only based on the temperature gradient, without offering detailed data regarding the machined material properties. It is crucial to understand the behaviour of the machined material in order to accurately assess the flushing efficiency, analyse the wear on the electrode, and examine the interaction between the debris generated during machining and the remaining workpiece. This is done to ensure that no recast material is left behind after the EDM process. For the first time, a meshless smoothed particle hydrodynamics multi-phase model was implemented to gain practical insights and comprehensively understand a very intricate phenomenon that occurs within a very short time. Additionally, this approach is utilised to investigate the characteristics of the materials being machined. We utilised our SPH model to simulate both the capacitance- and transistor-based EDM of Ti–6Al–4V and AISI304 steel. Our simulation considered the temperature-dependent thermal properties and latent heats of the materials. The accuracy of our model was confirmed by comparing its results with experimental, analytical, and finite element analysis (FEA) results. The machined material was observed during its removal from the surface, and the dimensions of the resulting crater, as well as its aspect ratio and the rate at which the material was removed, were predicted with an error ranging from 2 to 22%. This error is far lower than that of the typical finite element (FE) prediction. This model lays the groundwork for a more complex model that will more accurately represent EDM and other similar manufacturing processes. [ABSTRACT FROM AUTHOR]

The present study intends to investigate the impact of fractionation and micronization on the compositional, functional, and thermal characteristics of two protein concentrates derived from corn and barley. Fractionation of protein concentrates (by sieving) resulted in three fractions, i.e., fine (< 100 µm), medium (100–300 µm), and coarse (> 300 µm), while micronization resulted in an average particle size of 30 µm. No specific pattern was observed between particle size and chemical composition of corn and barley protein concentrates due to the complex interplay between particle size, surface area, structural changes, and botanical origin. Protein solubility varied depending on the pH and particle size, showing that the coarse fraction exhibited higher solubility than the fine fraction. For both corn/barley protein concentrates, coarse fraction had higher water-/oil-holding capacity. The barley fine fraction showed high foaming capacity, while all proteins lacked emulsification ability. Across all samples, a trend of increasing enthalpy with decreased particle size was observed, except for micronized barley, where enthalpy decreased, indicating possible protein structural changes. Thus, variations in properties among fractions highlight the importance of particle size in determining the proteins' functionality for potential applications in food systems. [ABSTRACT FROM AUTHOR]

In the present study, the fatty acid composition (FAC), triacylglycerol (TAG) composition, crystallization, and melting behaviors of mango kernel fats (MKFs) extracted from seven Ivorian mango varieties—Amelie (AM), Kent (KT), Palmer (PR), Keitt (KI), Brooks (BR), Dadiani (DI), and Djakoumankoun (DN)—were characterized by complementary techniques: pNMR, DSC, polarized light microscopy, and X-ray diffraction. Regardless of the variety, Ivorian MKF is rich in stearic (St) and oleic (O) fatty acids. (72–84% of the total FA), with three main TAGs: StOSt (23.9–45.8%), StOO (15.5–25.8%), and StLSt (10.4–12.5%). Their crystallization onset temperature (Tco) ranged from 15 to 20 °C. All samples showed complete melting around 35 °C, except DN (~ 38 °C). The β-polymorph appeared to be the most predominant and stable polymorph for the seven MKFs. The thermal properties investigated were linked to monounsaturated and triunsaturated triacylglycerol content, indicating the significant influence of chemical composition. The fine analysis of the results allows the seven Ivorian varieties to be divided into four groups, based on both their physical properties and thermal behavior, and the StOSt wealth: hard high-StOSt fat (DN), half-hard medium-StOSt fat (DI, BR), soft low-StOSt fat (KT, PR, KI), and very-soft very-low-StOSt fat (AM). The seven investigated mango varieties from Ivory Coast might offer a wide range of applications in food, pharmaceutical, and cosmetic industries. [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 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]

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]

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]

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]

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]

Thermal conductivity of moulding sands is very poorly known. In addition, the study of thermal conductivity variation of moulding sand as a function of its properties is a crucial step in the prediction of moulding defects. So, this study investigates the effects of moisture content, compactibility and permeability of green sand on its thermal conductivity variation, with a specific focus on the combination of bentonite, sand and water for thermal characterization of the transient hot-bridge (THB) method. Three levels of active clay content were selected: 8.1%, 8.98% and 10.03%. For each level of active clay, different mixes were made by varying the amount of added water. Compactibility, permeability and thermal conductivity tests were carried out for each combination of active clay and moisture contents. The experimental results show that thermal conductivity increases with water content and compactibility for different active clay contents, whereas thermal conductivity decreases with permeability, and this variation is highly significant especially for 8.07% of active clay content. [ABSTRACT FROM AUTHOR]

In this paper, a novel composite phase change material (CPCM) is prepared with inorganic PCM through impregnation and dispersion method which can be used for thermal management applications. Inorganic PCMs have high latent heat and good thermal conductivity and are non-flammable, but there exist leakage (shape stability) and corrosion problems. To overcome these issues, a porous structured material is impregnated with the inorganic PCM (disodium hydrogen orthophosphate dodecahydrate). The CPCM is prepared by loading various wt% of expanded graphite and boron nitride nanoparticles with the PCM, and characterization is performed to find the thermal properties and stability. The findings from FTIR and XRD analyses validate both the chemical compatibility and crystalline nature of the samples. DSC thermographs reveal the CPCM5 sample has a latent heat value of 168.05 J/g during the heating process, an encapsulation efficiency of 78.8% and a thermal conductivity of 4.69 W/mK. The thermal stability and resistance to corrosion of the composite samples are also enhanced. The best composite PCM sample is then selected, and subsequently, the thermal performance of the heat sink is experimentally investigated. The thermal performance of rectangular cavity heat sink filled with CPCM5 is the highest for various power sources and temperatures with a maximum enhancement ratio of 6.57. [ABSTRACT FROM AUTHOR]

The evolution of grain size in AA6XXX extruded profiles is a critical factor for enhancing mechanical, thermal and surface properties. Traditional methods for microstructure control rely on extensive experiments requiring significant time and resources. To address this issue, the present work proposes a method for microstructure prediction combining numerical data from Finite Element Method (FEM) simulations with experimentally acquired microstructure data to train an Artificial Neural Network (ANN) capable of predicting grain size. Data was acquired for three distinct AA6063 aluminum alloy profiles extruded under various process conditions in terms of profile and tool geometry, ram speed, billet pre-heating temperature and extrusion ratio, representing a diverse and heterogenous dataset comprising grain size (55–228 µm), strain (2.8–28), maximum strain rate (2–190 s−1), exit temperature (480–580 °C), Zener-Hollomon parameter (4 × 1015–4 × 1017) and Stored Energy (170–480 kJ/mol*K) for training and testing different ANN configurations. The final trained ANN was able to accurately predict grain size in regions of normal grain growth but was less reliable at foreseeing formation of the largest and smallest grains due to limited data points within this range. A Mean Absolute Percentage Error (MAPE) of 13.9% was achieved for predictions in the test set with an ANN comprising two fully connected layers with 9 and 19 neurons, respectively, Rectified linear unit (ReLU) activation functions and a ridge L2 penalty term of 10−6 for regularization. The presented methodology provides a foundation for the development of new data-driven approaches aimed at facilitating microstructure prediction in industrial settings. [ABSTRACT FROM AUTHOR]