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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]

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]

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]

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]

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]

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]

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]

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]

This study presents the eco-friendly composites coating with advanced properties that are prepared by chitosan (CS)-modified graphene oxide (GO) filled acrylic-based coating. Photo-curable acrylic-based nanocomposite containing different amounts of chitosan-modified graphene oxide (CS–GO) and the effect of CS–GO on the coating morphology, UV-curing, transparency, tribological, antimicrobial, thermal and anticorrosion properties was studied. The curing study confirmed that the CS–GO absorbed photon but did not affect the final conversion of the coatings. The results of corrosion analysis demonstrated that the CS–GO filled nanocomposite coatings have higher corrosion protection ability than that of pure acrylic and GO filled coatings. The antimicrobial properties of CS–GO filled coating showed that the antimicrobial performance enhanced as the concentration of CS–GO increased. The optical transmittance study shows that the coating's film transparency decreased with increasing CS–GO concentration, but all of the nanocomposite coatings have a high visible transmittance. This study attributes the enhanced properties to the dispersion of the chitosan-modified GO, which greatly improved the interfacial strength of CS–GO and polymeric matrix and enhanced corrosion properties. [ABSTRACT FROM AUTHOR]

This research investigates how the thermal, electrical, and hydrophobic characteristics of a nanocomposite coating, which includes grape seed essential oil, are affected by the incorporation of silane-treated nanosilica. The main goal of the study is to create an environmentally friendly polymeric coating and evaluate how the inclusion of grape seed oil and nanosilica influences its performance. The nanosilica was silane-treated using 3-Aminopropyletrimethoxysilane and the coating materials were prepared using blend mixing and casting. Numerous characterizations such as mechanical, thermal, dielectric, hydrophobic and fractography were conducted on the coating material in accordance with ASTM standards and significant findings were obtained. The microstructural analysis via scanning electron microscopy indicated that grape seed oil dispersion is uniform and no distinct lumps identified. Further the nanosilica contributed to improved thermal stability of coating material while maintaining lower dielectric constant and water intake properties. The EOS3 composite coating containing 25 vol. % grape seed oil, with 5 vol. % of nanosilica provided the relative permittivity of 2.81, loss factor of 0.064 and thermal conductivity of 0.228 W/mK, which is equal to plain resin indicating the addition of nanosilica maintains lower permittivity and conductivity in-spite of grape seed oil addition. Moreover, the composite coating 'EOS3' provided high stability in thermal properties. Less mass loss of 2.16% with on-set initial decomposition temperature of 334°C were noted for EOS3 composite coating. The contact angle of 'EOS3' composite designation provided 74°, which is reasonably higher on compare with plain resin indicating still the composites are close to hydrophobic range. Finally, EOS2 (25 vol. % grape seed oil + 3 vol. % nanosilica) delivers better mechanical performance with maximum tensile strength of 59MPa. These bio-oil bended and nanosilica toughened vinyl ester based composite coating materials could be used in food packaging, medical industries and protection of metallic and non-metallic substrates for healthy life span with eco-friendliness. [ABSTRACT FROM AUTHOR]

This study utilizes a multidisciplinary approach, combining simulation experiments, thermal expansion analysis, XRD, SEM, and physical property assessments to investigate the firing temperature in illitic-kaolinitic porcelain. Our findings indicate that the accuracy of the thermal expansion method depends on both the actual firing temperature and dwell time. When dwell time is uncertain, the method provides a range of possible actual firing temperatures, differing by approximately 100 °C. Remarkably, as the porcelain body nears full vitrification, the determined firing temperature tends to be notably higher. A critical analysis of previous research suggests potential overestimation of ancient kiln temperatures. Additionally, our study highlights the usefulness of bulk density, water absorption, porosity, and mullite content in determining dwell time. Overall, our research offers new insights into ancient porcelain firing processes. [ABSTRACT FROM AUTHOR]

The advancement of implantable biomedical devices (IMDs) hinges on the development of biocompatible solid-state electrolytes with outstanding electrochemical performance, safety, and reliability for flexible solid-state supercapacitors. This study focuses on the development of gel polymer electrolytes (GPEs) using polyvinyl alcohol (PVA) and potassium chloride (KCl). The GPEs obtained were subjected to comprehensive characterization using a diverse range of techniques to evaluate their spectral features, morphological properties, thermal and mechanical performance, biocompatibility, ionic conductivity, and cyclic stability. What distinguishes our research is its comprehensive exploration of the profound impact of varying PVA molecular weights and PVA/KCl weight ratios on the ionic conductivity and thermal characteristics of these gels. Notably, we observed a decrease in ionic conductivity with increasing PVA molecular weight, whereas an increase in salt concentration under the same molecular weight led to higher ionic conductivity. In particular, the optimal gel electrolyte with a molecular weight (Mw) of 195,000 g/mol and a PVA/KCl weight ratio of 1/2 demonstrated a promising ionic conductivity of 3.48 ± 0.25 mS/cm. Even after 5000 cycles, it retained 88% of its initial specific capacitance. Our findings reveal that the GPEs exhibit remarkable mechanical robustness alongside unparalleled ionic conductivity, characterized by minimal interfacial resistance. Moreover, these gel electrolytes exhibit remarkable biocompatibility, evident in a cell viability test where 72.3% of cells remained unaffected after a 72-h exposure to PVA/KCl. These findings present a promising avenue towards the fabrication of stable and high-performance biocompatible gel polymer electrolytes which can be used in solid-state supercapacitors, thereby laying the foundation for their integration into flexible, safer, and wearable bio-electronics. [ABSTRACT FROM AUTHOR]

The traditional high-temperature preparation process of polyimide can cause many problems and limits the wider application in extreme conditions. An important challenge to be solved urgently is the reduction of imidization temperature. In this work, twelve kinds of polyimide films with different chain rigidity were prepared at low temperature of 200 °C, in the absence or presence of imidazole used as the catalyst. The molecular rigidity and free volume were theoretically calculated, and relationship between structure and properties were systematically studied. The results show that imidization reaction under low temperatures is significantly affected by the rigidity of molecular chains. The rigid structure of polyimide is not conducive to the low-temperature imidization, but this adverse effect can be eliminated by adding catalyst, resulting the notably increased imidization degree. The optical and thermal properties can be improved to a certain extent for the chemically catalyzed system, resulting in relatively higher heat resistance and thermal stability. While the mechanical performance could be determined by complicating factors, greatly different from polyimide films prepared by high temperature method. To investigate aggregation structures of films, the effect of chain rigidity and catalyst on the stacking or orientation of molecular chains was further elaborated. This work can contribute to the understanding of chemically catalyzed imidization that is rarely reported in the existing research, and will provide guidance for the low-temperature preparation of high-performance polyimides. [ABSTRACT FROM AUTHOR]

The thermophysical properties of molten salts promising for the nuclear industry are crucial, but the available data are limited and contradictory. The thermal diffusivity of the molten mixtures (NaF-KF)eut–UF4 containing 30, 40, and 50 mol % UF4 was measured by the laser flash method. The thermal diffusivity was found to be almost independent of temperature in the range of about 100° (1070 K–1170 K), which makes it possible to extrapolate values to low or high temperatures. The thermal conductivity of the molten mixtures (NaF-KF)eut–UF4 was calculated using the thermal diffusivity, density, and heat capacity data. Density was estimated using the molar volume of the molten binary systems NaF-UF4 and KF-UF4. The heat capacity of the ternary system NaF-KF-UF4 was evaluated based on the heat capacity of individual salts, taking into account the additivity law. The thermal conductivity of the molten mixtures 0.7(NaF-KF)eut–0.3UF4, 0.6(NaF-KF)eut–0.4UF4, and 0.5(NaF-KF)eut–0.5UF4 changes slightly with the UF4 content and temperature; for example, at 1123 K it is 0.48, 0.45, and 0.45 W·m−1·K−1, respectively. The thermal diffusivity of the pure molten UF4 was estimated using three independent approaches: the concentration, the temperature, and the volume dependences of the thermal diffusivity. The estimated value of the thermal diffusivity for the molten UF4 was about 0.12 × 10–6 ± 0.05 × 10–6 m2·s−1. [ABSTRACT FROM AUTHOR]

This study explores how the size and hybridisation of graphene nanoplatelets (GNPs) affect the properties of graphene nanoplatelet-filled natural rubber (NR) nanocomposites (GNP-filled NR). Results demonstrate notable enhancements in the thermal properties and electrical conductivity of NR with the addition of GNPs. However, mechanical properties experienced partial enhancement, showing increased modulus by up to 200% and hardness by up to 50%, alongside decreased tensile strength by up to 60% and elongation by up to 70%. The comparative analysis highlights the superior mechanical and thermal properties associated with smaller GNPs. These smaller particles enhanced mechanical properties such as modulus at 100% strain and Shore A hardness, increased the glass transition temperature by up to 10%, and reduced thermal degradation rates by up to 30% due to their superior dispersion and interfacial bonding with NR. Larger GNPs exhibited a 1000% increase in electrical conductivity at 10 × 106 Hz due to increased surface area and network formation due to reduced dispersion. Notably, hybrid GNPs contributed significantly to overall property enhancements compared to the single filler system, with up to 80% higher tensile strength, up to 30% higher elongation at break, up to 20% higher glass transition temperature, lower degradation rate at high temperature, attributed to improved dispersion of GNPs and interfacial adhesion with NR. This study highlights the substantial influence of GNP sizes on the performance of NR nanocomposites and the significant effects of hybridisation, providing valuable insights for optimising material properties for advanced applications. [ABSTRACT FROM AUTHOR]

To study the service performance of polymer bilayer sheets, this experimental study focuses on the thermal and mechanical characterization of sheets composed of two polymer layers (named ABS/PMMA), an Acrylonitrile–Butadiene–Styrene layer and a 15% Poly(Methyl Methacrylate) layer. These sheets are used in many industrial components subjected to thermal and mechanical strain. The studied bilayer sheets were obtained by a co-extrusion process. Thermal properties were measured through Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). Mechanical behavior was determined via uniaxial tensile tests at various temperatures less than the glass transition temperature and using two strain rates of 3.33 × 10−4 s−1 and 1.66 × 10−2 s−1. Furthermore, the viscoelastic properties are determined via Dynamic Mechanical Analysis (DMA) using two frequencies. The findings revealed substantial ABS/PMMA bilayer thermal stability. The obtained glass transition temperature of this bilayer was 111 °C. Its viscoelastic behavior was described by determining the storage and loss modulus. Furthermore, the influence of temperature and strain rate parameters on the tensile behavior of the ABS/PMMA bilayer was also determined showing high dependence of mechanical behavior on these two parameters. This bilayer exhibits brittleness at room temperature and high total strain exceeding 62% at 90 °C. [ABSTRACT FROM AUTHOR]

Ashes from various Polish coal-fired power plants were analysed in this investigation as the source material for preparing simulants of lunar regolith. The chemical and phase constituents were the most important parameters used to describe these ashes. The second parameter was particle size and morphology, specifically characterising technological properties such as flowability or density. The final element of the investigation was related to the characterisation of thermal properties. Differential thermal analysis yields information on phase transitions, melting temperatures and other characteristic temperatures of stimulants. Thermogravimetry with Fourier transform infrared analysis provides information on evolved gas species and their evolution temperature profiles. [ABSTRACT FROM AUTHOR]

The combination of cellulose nanocrystals (CNCs) with synthetic polymers like polypropylene (PP) offers the opportunity to create advanced nanocomposites with significant advantages in terms of mechanical properties, improved thermal stability, enhanced barrier properties, and sustainability. However, a major drawback for incorporation of CNCs in polymer matrices is their poor dispersion and incompatibility with industrial processing of many composites. This work aims to improve the dispersion of hydrophilic CNCs in a hydrophobic matrix using a method which could be adapted for the industrial level. CNCs are extracted from Ampelodesmos mauritanicus (El Diss plant) (CNCD) and incorporated in a polypropylene matrix using the masterbatch method. A first nanocomposite (PP/CNC-Gr) was prepared by adding maleic anhydride (MA) to a CNCD/PP suspension, while the second nanocomposite (PP/CNC-Co) was achieved by using a MA-grafted PP (PP-g-MA) as a third component. Concentrated masterbatch underwent solution casting followed by homogenization in a Brabender mixer. Mechanical properties comparison showed that PP/CNC-Co nanocomposites exhibited greater resistance relatively to PP/CNC-Gr nanocomposites. Moreover, PP/CNC-Co nanocomposites revealed an improved thermal stability and a higher complex viscosity, particularly with 3% of CNCD. Properties enhancements are attributed to the reaction between MA groups grafted to PP chains and hydroxyl groups of CNCDs, which enables an improved interfacial adhesion, leading to more continuous materials, as perceived from the increase in viscosity and morphology observation. On the other hand, MA reaction with PP chains and CNCD induced only a partial coverage of CNCDs during nanocrystals treatment, conferring relatively lower properties to PP/CNC-Gr nanocomposites. [ABSTRACT FROM AUTHOR]

Composites are fabricating by reinforcing waste bambara nut shell powder (BNSP) as a bio-filler into an epoxy resin matrix. The composite is fabricated by varying the mass fractions of filler in the range of 5–35 wt%. The effects of bio-filler content on physical, mechanical, and thermal properties are evaluated. The studies reveal that the tensile strength, tensile modulus, flexural strength, and impact strength increased with increasing bio-filler content. The highest mechanical properties of BNSP-loaded epoxy composites are achieved at bio-filler mass content of 15 wt%, whereas hardness increased for 5–35 wt% with peak value at 35 wt%. The water absorption and thickness swelling of the BNSF/epoxy composites increased with increasing bio-filler contents, while the density decreased with an increase in bio-filler content. The TGA results revealed that an increasing bio-filler content decreased thermal stability, whereas the Tg and Tm of the composites increased with increasing bio-filler content. [ABSTRACT FROM AUTHOR]

PC/ABS blends are commonly used for the production of automotive components due to their thermal and mechanical properties. However, changes in process conditions can have a significant impact on their properties and microstructure. Therefore, determining the optimal parameters for the injection molding (IM) process is critical for effective control of the mechanical properties and quality of the injected parts. In this study, the Taguchi method is applied to investigate the relationship between the tensile stress (σ), Young's modulus (E) and IM process of PC/ABS blends. The effects of different molding parameters such as material temperature, injection pressure, holding time and mold temperature were investigated. The optimal injection parameters to achieve higher tensile stress (σ) and Young's modulus (E) were predicted by studying the signal-to-noise ratio (S/N). Thus, the objectives of the Taguchi approach for the IM process are to determine the optimal combination of process parameters and to reduce the quality variations between only a few trials. Two optimal parameter combinations were found yielding very significant mechanical properties (σ, E) of the injected parts. These optimum combinations consist of material temperature of 260 °C, injection pressure ranging between 40 and 50 bar, holding time of 8 s and mold temperature of 60 °C. Experimental results prove that injection pressure and material temperature have the most significant impact on the mechanical properties and the microstructure of PC/ABS blends. These findings may have interesting applications in the automotive industry. [ABSTRACT FROM AUTHOR]

The melt quenching technique was used to prepare tellurite glasses with compositions 70TeO2–20BaO–10WO3 (BT:W glass), 70TeO2–20BaO–10Y2O3 (BT:Y glass), 70TeO2–20BaO–10SrO (BT:Sr glass) and 70TeO2–20BaO–10Li2O (BT:Li glass). The impact of modifying ions Ba2+, W6+, Y3+, Sr2+, and Li+ on structural, physical, thermal and mechanical properties of the prepared glasses has been explored by using XRD, DTA, and FTIR spectroscopic techniques. XRD analysis conformed that the prepared glasses are amorphous and homogeneous in nature. The FTIR spectra revealed the presence of TeO4 trigonal bipyramids, TeO3 trigonal pyramids and NBOs in the network of BT:Y, BT:Sr and BT:Li glasses. Meanwhile, the structure of BT:W glass is composed of TeO4, TeO3, WO4 and WO6 units, which are connected to each other through W–O–Te linkages. The glass transition temperature and thermal stability increased in the order BT:W glass > BT:Y glass > BT:Sr glass > BT:Li glass. These results were compared to those of binary 80TeO2–20BaO glass (BT) and pure TeO2 glass. Changes in the thermal properties have been analyzed and predicted by correlating them with the calculated molar volume, ratio of packing density to mean atomic volume, dissociation energy per unit volume, field strength of the modifying ions, average single bond strength, and elastic moduli. The R-squared values of the regression lines can be improved if the effect of all structural groups as well as the uncertainty inherent in experimental measurements are taken into account. The highest thermal stability and glass transition temperature of BT:W glass making it a good candidate for shielding material in the fields of medical, industrial, and nuclear applications. [ABSTRACT FROM AUTHOR]

It is important to utilize the raw colemanite (RC) mineral, which has abundant reserves in the world, and to reduce its particles to smaller sizes for nanotechnology. However, not only the particle size of the produced colemanite powder but also its other properties need to be elucidated. By using the Taguchi design, the RC mineral was ground in a high-energy ball mill. From signal-to-noise (S/N) ratio, the smallest average particle size was found to be 3.10 µm for the experiment E04/nano-sized amorphous colemanite (NAC) powder. The characteristics of as-received RC mineral and synthesized NAC material were investigated using laser particle size analyzer, optical microscopes, SEM–EDS, XRD, TEM, HRTEM, and TGA–DTA devices. It was found that the NAC powder was not homogeneous, a small peak within the 300–20 nm range appeared, and d90, d50, d10, and dmin values were, respectively, 14.6 µm, 3.08 µm, 232 nm, and 26 nm. In the XRD analysis, the pure colemanite, calcite, and silica minerals were determined. The crystal structure of the NAC powder almost turned amorphous, and the crystallite size of (031) peak was reduced to 7.3 nm. It was deduced that the average particle size was 8.29 nm (R2 = 0.86), and the d-spacing value was 0.307 nm. This significant finding was attributed to the mobility of balls and moreover it was interpreted with an equation. An unknown transition in TGA–DTA was referred to the calcite mineral. Finally, it is believed that the synthesized NAC material will be beneficial to engineering studies as a natural/mineral additive. [ABSTRACT FROM AUTHOR]

Context: Traditional conductive adhesives based on epoxy resin system often encounter problems such as high brittleness and low heat resistance. Therefore, it is particularly important to improve the thermal and mechanical properties of the conductive adhesive. In this study, the effects of SWCNT-Ag and SWCNT fillers on the thermal properties of DGEBA/DETA/Ag conductive adhesive system were studied by using molecular dynamics to construct different cross-linking models. The final results show that the addition of SWCNT and SWCNT-Ag can significantly improve the thermal properties of the conductive adhesive. However, the nanosilver particles on the surface of SWCNT-Ag act as a bridge for the connection between SWCNT and Ag in the conductive adhesive. Therefore, SWCNT-Ag has a more positive impact on the thermal properties of DGEBA/DETA/Ag conductive adhesive system. Methods: In this paper, the influence of SWCNT-Ag on the thermal properties of traditional DGEBA/DETA/Ag conductive adhesive system was studied by using Materials Studio software. The volume shrinkage, glass transition temperature, thermal expansion coefficient, and thermal conductivity of the material were calculated based on COMPASS force field. The thermal conductivity is calculated by using reverse non-equilibrium molecular dynamics method. Finally, it is found that SWCNT-Ag has a positive effect on the thermal properties of the conductive adhesive system by comparing several groups of calculation data. [ABSTRACT FROM AUTHOR]

Three new hexacyanometallate(III) complexes, namely {[Cd3(4epy)12Cr2(µ-CN)6(CN)6]∙4H2O}n (1), {[Cd3(4epy)12Fe2(µ-CN)6(CN)6]∙4H2O}n (2) and {[Cd3(4epy)12Co2(µ-CN)6(CN)6]∙4H2O}n (3), were synthesized by using 4-ethylpyridine (4epy) ligand and characterized by spectral (FT-IR and Raman), crystallographic (SC-XRD and PXRD), thermal and elemental analyses techniques. Single crystal studies have shown that heterometallic complexes 1–3 form 3D polymers. Each M ion [M = Cr(III) in 1, Fe(III) in 2 and Co(III) in 3] is coordinated by six carbon atoms from cyanide ligands and adjacent metal ions are bridged by cyanide ligands to generate [Cd6M6(CN)12] clusters. Each Cd(II) ion is coordinated by four nitrogen atoms from 4epy ligands and two nitrogen atoms from cyanide ligands to distorted octahedral coordination geometry. In addition, thermal (TG/DTA) properties of the complexes were investigated. Powder X-ray diffraction (PXRD) patterns of the complexes were recorded to control the phase purities. [ABSTRACT FROM AUTHOR]

The microstructure and temperature dependence of linear thermal expansion and elastic properties of a two-phase, A2 + B2, Al10Nb20Ta15Ti30V5Zr20 refractory superalloy (RSA) and its constituent phases are reported. After slow cooling from 1400 °C, this alloy has a nanometer-sized, two-phase microstructure consisting of Nb-rich BCC (A2 crystal structure) cuboidal precipitates at the volume fraction of 0.63 and continuous channels of a Zr-rich ordered B2 matrix phase. This two-phase microstructure forms by spinodal decomposition of a high-temperature BCC phase. Differential scanning calorimetry shows that the order–disorder transformation in the Zr-rich phase occurs in the temperature range of 550 °C to 850 °C. The coefficient of thermal expansion (CTE) of the Nb-rich BCC phase increases slightly from 8.9 × 10−6 to 9.1 × 10−6 K−1 with increasing temperature from 20 °C to 1200 °C. The Zr-rich phase has CTE of 9.1 × 10−6 K−1 in the ordered (B2) state, at 20 °C to 550 °C, and 12.2 × 10−6 K−1 in the disordered (A2) state, at 900 °C to 1200 °C. The Nb-rich phase has higher Young's and shear moduli, but lower bulk modulus and Poisson's ratio, as compared to the Zr-rich phase, at 20 °C to 600 °C. The CTE and elastic properties of the two-phase RSA approximately follow the rule of mixtures of the constituent phases in the studied temperature ranges. Correlations between the morphology of the spinodally decomposed microstructure in the two-phase RSA and the thermal and elastic properties of the constituent A2 and B2 phases are established. [ABSTRACT FROM AUTHOR]

The present study explores the influence of Cobalt oxide nanoparticles(Co3O4 NPs) on the physicochemical characteristics of Poly(vinylalcohol)/ Chitosan (PVA/Cs) blend. Using a variety of techniques, the pure blend and the nanocomposites' composition, structure, optical, thermal, and mechanical properties, and antibacterial activity were characterized. The Co3O4 NPs were produced by precipitation method utilizing cobalt salt as the raw material. The crystalline nature of the nanoparticles and semi-crystalline behavior of the PVA/Cs are demonstrated by the XRD data. Adding nanoparticles to the pure blend reduced the intensity of the semi-crystalline. The rise in absorption intensity observed in UV-visible spectra upon the incorporation of Co3O4 NPs into the PVA/Cs blend indicates an improved dispersion of the nanoparticles within the blend. When Co3O4 NPs are added, the energy band-gap Egdir and Egind of PVA/Cs–Co3O4 samples greatly decrease. According to TGA data, the thermal stability of nanocomposites was significantly higher than that of the PVA/Cs blend, and it rose as the concentration of nanoparticles increased. When compared to neat PVA/Cs film, mechanical property investigation of PVA/Cs–Co3O4 nanocomposites films revealed enhanced features. The effectiveness of the PVA/Cs–Co3O4 nanocomposite films in inhibiting the growth of microorganisms was assessed by evaluating their antimicrobial activity (ANMAC) against a range of bacteria and fungi. The inclusion of Co3O4 NPs led to an increase in activity against Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli) bacteria as well as fungi Candida albicans and Aspergillus niger (C. albicans and A. niger). The addition of Co3O4 NPs to the PVA/Cs blend effectively improved the material's optical, thermal, mechanical, and antibacterial properties. This remarkable improvement stems from the Co3O4 NPs, which were introduced into the PVA/Cs blend in different amounts, leading to the development of novel nanocomposites. The outstanding properties of Co3O4/PVA/Cs nanocomposite films suggest their potential for applications in optoelectronics and food packaging. [ABSTRACT FROM AUTHOR]

Waste cooking oil (WCO) from various sources were evaluated as low-cost carbon feedstock to produce poly[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyhexanoate] [P(3HB-co-3HHx)] copolymer, which is a type of polyhydroxyalkanoate (PHA). Different Cupriavidus necator transformants harbouring phaCBP−M−CPF4 were employed as PHA-producing organisms in one-stage cultivation in shake flasks. Biological and chemical recovery of PHA were evaluated. C. necator Re2058/pHT1-CBP−M−CPF4 was able to achieve a cell dry weight (CDW) of 8.5 g/L, PHA content of 75.5 wt% and PHA concentration of 6.4 g/L from 1% (v/v) WCO. The weight-average molecular weight (Mw) of the synthesized PHA obtained from the same strain was 1440 kDa. The CDW, PHA content and concentration acquired using WCO are comparable to those using fresh oils as carbon substrates. The copolymer produced from distinct sources of WCO and different extraction methods did not have significant differences in molecular weights and thermal properties. Mealworms can perform biological recovery of PHA from cells fed with WCO from distinct sources. This study suggests that WCO from any source can be used as carbon source for bacteria to produce PHA. WCO can be a sustainable alternative for the more expensive fresh oils, and the synthesized PHA can be biologically recovered by mealworms. A combination approach of utilising low-cost substrate such as WCO, high-performance PHA producer including C. necator transformants and biological recovery to extract PHA is beneficial in biosynthesis of PHA copolymer, since this can make PHA production more economical and can improve the ability of PHA to compete with conventional petrochemical plastics. [ABSTRACT FROM AUTHOR]

Stereolithography (SLA) is a highly versatile additive manufacturing technique that utilizes various ink formulations to fabricate 3D-printed nanocomposite structures with desired properties. Zinc oxide (ZnO) is a promising candidate due to its excellent mechanical and thermal stability, and compatibility with various polymeric matrices. In this work, varying ink formulations containing ZnO nanoparticles, along with employing appropriate post-printing curing parameters to fabricate SLA 3D-printed acrylate-based nanocomposites with improved mechanical and thermal properties, were reported. This study can significantly contribute to expanding its potential use in practical applications such as biomedical and structural applications. [ABSTRACT FROM AUTHOR]

This study focuses on the development of a nanocomposite membrane using polyvinyl chloride and nanocellulose@titanium aluminate to effectively filter and adsorb dye from wastewater. Various analytical techniques were used such as FTIR, XRD, SEM, and TGA to characterize the synthesized adsorptive nanocomposite membrane. The thermal and electrical properties of the membrane were measured using a static system. The study investigated the effect of different adsorbent dosages, pH levels, and dye concentrations on the membrane's adsorption ability. The PVC-NC@TALCM nanocomposite membrane was found to remove 98.6% of MB dye when loaded with 5% titanium aluminate at pH 10. Kinetic and isotherm studies revealed that the adsorption of MB onto the membrane followed pseudo-second-order kinetics and Freundlich isotherms, respectively. The researchers also highlighted the economic and eco-friendly nature of the PVC-NC@TALCM nanocomposite membrane as a viable option for the removal of MB from industrial wastewater. [ABSTRACT FROM AUTHOR]

In this study, poly(l-lactide-co-ε-caprolactone) (PLCL) block copolymers with an ABA structure were prepared using a two-step polymerization process, and their microstructures, thermal, and mechanical properties were systematically investigated based on the introduction of ε-caprolactone as a comonomer in the first step to form the B block. As a result, it was observed that as the content of the B block, or the ε-caprolactone comonomer increased, the average sequence length of l-lactide decreased, indicating that a potential impact on the crystallization behavior and thermal properties of the final PLCL block copolymers. However, the decrease in thermal properties, such as the melting temperature, was less significant than expected. For instance, the melting temperature of pure PLA in this study was 172.5 °C, whereas the PLCL block copolymer with 9 mol% ε-caprolactone comonomer had a melting temperature of 171.1 °C, showing a relatively minimal difference between the two samples. Additionally, as the ε-caprolactone content increased, tensile strength and initial modulus of the PLCL block copolymer slightly decreased, while the breaking strain significantly increased. This suggests that the two-step polymerization method proposed in this study is effective in imparting flexibility to PLA while minimizing its mechanical property degradation. Consequently, the introduction of comonomer such as the ε-caprolactone through controlled polymerization process offers valuable insights for developing PLA materials with diverse properties. [ABSTRACT FROM AUTHOR]

The thermophysical properties of molten salts promising for the nuclear industry are crucial, but the available data are limited and contradictory. The thermal diffusivity of the molten mixtures (NaF-KF)eut–UF4 containing 30, 40, and 50 mol % UF4 was measured by the laser flash method. The thermal diffusivity was found to be almost independent of temperature in the range of about 100° (1070 K–1170 K), which makes it possible to extrapolate values to low or high temperatures. The thermal conductivity of the molten mixtures (NaF-KF)eut–UF4 was calculated using the thermal diffusivity, density, and heat capacity data. Density was estimated using the molar volume of the molten binary systems NaF-UF4 and KF-UF4. The heat capacity of the ternary system NaF-KF-UF4 was evaluated based on the heat capacity of individual salts, taking into account the additivity law. The thermal conductivity of the molten mixtures 0.7(NaF-KF)eut–0.3UF4, 0.6(NaF-KF)eut–0.4UF4, and 0.5(NaF-KF)eut–0.5UF4 changes slightly with the UF4 content and temperature; for example, at 1123 K it is 0.48, 0.45, and 0.45 W·m−1·K−1, respectively. The thermal diffusivity of the pure molten UF4 was estimated using three independent approaches: the concentration, the temperature, and the volume dependences of the thermal diffusivity. The estimated value of the thermal diffusivity for the molten UF4 was about 0.12 × 10–6 ± 0.05 × 10–6 m2·s−1. [ABSTRACT FROM AUTHOR]

Apparent thermal conductivity of soil (λ) as a function of soil water content (θ), i.e., λ(θ) is needed to determine the heat flow in soil. The function of λ(θ) can be used in heat and water flow models for simplicity. The objective of this study was to develop a sigmoidal model based on logistic equation for entire range of soil water contents and a wide range of soil textures that can be used in simulation of heat and water flow in respected modes. Further, performance of the developed sigmoidal model along with two other models in literature was evaluated. In the proposed sigmoidal model, the constants of this model are estimated based on empirical multivariate equations by using soil sand content and bulk density. The sigmoidal model was validated with good accuracy for a wide range of soil textures, as the relationship between the measured and predicted λ showed slope and intercept values of nearly 1.0 and 0.0, respectively. Comparison of the results obtained by sigmoidal model with those obtained from Johansen and Lu et al. models indicated that, the sigmoidal model was superior to the other two models in prediction of λ for a wide range of soil textures and soil water contents. Furthermore, comparison with a recently proposed model by Xiong et al. indicated that our sigmoidal model is superior. Therefore, our developed sigmoidal model can be used in heat and water flow models to predict the soil temperature and heat flow. [ABSTRACT FROM AUTHOR]

Increasing the surface quality of porcelain tiles, preferred in public, commercial, and living centers, where human density is high, is one of the crucial goals. Surface applications can be applied on the tiles produced as glazed and unglazed tiles in different versions. In lappato glazed tiles, staining-resistance is of great importance besides glossy-surface and wear-resistance. In this study, technical properties such as staining, chemical agent-resistance, color-parameters, thermal-behavior (heat microscopy), roughness, abrasion resistance, and microstructure of glazes (SEM/EDS) depending on the optimizing grinding time were examined with compared to standard lappato-glaze under the industrial conditions. It was observed that with the increase of the glaze grinding, the whiteness value and the increasing smoothness, and higher staining chemicals resistance and the glaze which has lower characteristic temperatures than the standard. As the surface roughness decreased due to grinding, the number and size of pores in the microstructure decreased. The glassy phase exhibited homogeneous distribution due to the dissolution of anorthite crystals. [ABSTRACT FROM AUTHOR]

FFF (fused filament fabrication) is a type of 3D printing that utilizes filament for part creation. This study proposes using by-products or waste to replace part of the plastic in FFF filament, reducing environmental impact. The aim is to maintain a simple manufacturing process involving extrusion on a single-screw desktop machine followed by printing. The plastic matrix comprises polylactic acid (PLA) and polyethylene glycol (PETG), with added powdered by-products: seashells, car glass and mill scale (metal). Additives will be incorporated at 10% and 20% by weight, with two grain sizes: up to 0.09 mm and up to 0.018 mm. Mechanical tests (tensile, flexural and hardness) and thermal characterization tests will be conducted. Findings suggest adding 10%w powder of any variety to PETG increases tensile strength up to 48%, with metal powder (mill scale) showing the highest enhancement, even at 20%w, resulting in a 41% increase. Conversely, adding powder to PLA worsens mechanical properties without stiffening the material; instead, the elastic modulus decreases. Metal grain size has minimal impact, with grain sizes lower than 0.09 mm optimal for PLA. Thermal conductivity in polymers blended with powder additives is lower than in virgin polymers, likely due to air void formation, supported by density and microscopic evaluations. This research underscores the potential of utilizing waste materials with a simple FFF filament production to enhance sustainability in 3D printing practices. [ABSTRACT FROM AUTHOR]

This paper presents a study on the thermal and electrical performance of lattice structures designed for a heat exchanger, where the geometry is optimized for enhanced heat management through a numerical simulation scheme based on the response surface method. The goal was to achieve effective heat conduction and convection. Lattice structures were selected for their inherent porosity, enabling efficient heating and cooling cycles. The optimized lattice geometry was fabricated using Laser powder bed fusion (L-PBF) additive manufacturing, with a "green" laser emission wavelength (λ = 515 nm) to improve energy absorption and final product density. Experimental evaluations assessed the thermal and electrical performance of the L-PBF-produced samples, including both workpieces and lattice structures designed for additive manufacturing. Microscopic and microstructural studies were conducted to identify potential manufacturing defects, such as porosities and cracks, resulting from the L-PBF process. Despite some defects persisting in certain lattice structures, the results showed significant improvements in both thermal and electrical properties compared to those obtained using the traditional infrared laser L-PBF process. An enhanced 3D-printed heat exchanger design is proposed, emphasizing lattice-like internal structures. This advancement offers superior control, increased durability, and improved safety for hydrogen storage devices. This research represents a significant contribution to the field of heat exchanger design and additive manufacturing, especially in the context of hydrogen storage technologies. It demonstrates the potential for lattice structures and innovative manufacturing processes to revolutionize the efficiency and safety of thermal systems. [ABSTRACT FROM AUTHOR]

Polybutylene terephthalate (PBT) nanocomposites were melt-blended with two types of Turkish halloysite nanotubes (HN). Naturally occurring HN samples were used to produce PBT-based composites at the HN compositions of 1%, 3%, 5%, and 10%. Findings of neat and silane-coated HN-containing composite samples were compared to investigate the interfacial adhesion between polymer matrix and reinforcement material. According to test results, a 1% amount of HN was found to be the most suitable option in the case of mechanical and thermal properties of composites. Additionally, silane-modified grade displayed highly indicative improvements compared to pristine HN clay due to better interfacial adhesion of halloysite nanotubes to the PBT matrix was accomplished. Property enhancements achieved for composite samples containing low contents of HN were confirmed by morphological examinations. As a result, the PBT/ 1% HN-S composite sample was bookmarked as the most suitable option to fabricate HN-reinforced PBT-based nanocomposites in terms of mechanical, thermo-mechanical, morphological, thermal, and physical performances based on the findings in this study. Silane-modified halloysite grades exhibited better results, and they were found to be more suitable in the case of applications of PBT. [ABSTRACT FROM AUTHOR]