Ordered alkene-alkyne alternating conjugation in polyimides: A dual-strategy approach to ultralow dielectric constant and high thermal conductivity.

Understanding starch behavior under various processing conditions is important for the development of novel food products with tailored nutritional profiles. This study investigated changes to the structure and properties of native corn starch (NCS) and biomimetic starch-entrapped microspheres following thermal and enzymatic treatments. Heat-treated microspheres showed more birefringence and structural order than native starch, indicating incomplete gelatinization due to the alginate matrix. Microspheres (MC-1 and MC-2) exhibited lower pasting viscosities. Larger particles retarded viscosity development. Enzyme kinetics showed higher apparent maximum reaction velocity (Vm) but an increased Michaelis constant (Km) for microspheres in comparison with native starch. The elevated Km reflects reduced enzyme affinity due to the alginate barrier, and the higher Vm results from transiently high local substrate concentration on the surface. Digestion progressed from the outer layer toward the core, with MC-2 retaining higher crystallinity and structural integrity after 120 min because of the protective effect of the alginate matrix. Thermal analysis demonstrated that gelatinization onset (Tₒ), peak (Tp), and conclusion (Tc) temperatures increased with digestion time in all samples and the enthalpy change (ΔH) decreased, consistent with structural reordering after digestion. The alginate shell in microspheres effectively delayed amorphous region hydrolysis, enhancing thermal stability. Consequently, the rapidly digestible starch (RDS) content decreased from 84.54% in NCS to 47.06% in MC-2, whereas the resistant starch (RS) and slowly digestible starch (SDS) content increased from 20.42% to 44.21% and from 7.90% to 34.90%, respectively. Alginate encapsulation enhanced the thermal properties of starch and increased its slowly digestible and resistant starch content by forming biomimetic starch-entrapped microspheres. © 2025 Society of Chemical Industry.

Heat exchangers are widely recognized as eco-friendly devices that transfer heat between two or more fluids without mixing. Double Pipe Heat Exchangers (DPHE) are used in many industrial applications such as power generation, chemical processing, HVAC, and renewable energy systems. Traditional DPHEs are simple and reliable, however, they often face limitations in heat transfer. Improving the thermal performance of DPHE can significantly enhance the operational efficiency of thermal energy systems. This study presents a novel fin arrangement to the traditional DPHE using different diamond-shaped fins to improve its thermal performance. The thermal and hydraulic properties of DPHE with different diamond-shaped fin configurations are investigated using CFD analysis. The optimization process is carried out using the Response Surface Method (RSM) for optimal diamond-shaped fin design. The results indicate that novel diamond-shaped fins improve thermal performance, particularly at high mass flow rates. The thermal enhancement factor (TEF), overall heat transfer coefficient, and pressure drop are used to evaluate the thermal performance of DPHE. The diamond-shaped fins exhibit a 55% increase in overall heat transfer coefficient compared to conventional DPHE. The TEF for diamond-shaped fin configurations is higher than 1 with a maximum value of 1.63 for DPHE-HF45 depicting a 63% increase in thermal enhancement. The optimization results show that the optimal fin design achieves a desirability of 81.3%, with a pressure drop of 870.726 Pa and an overall heat transfer coefficient of 2199.85 W/m 2 K at a mass flow rate of 2.711 lit/min.

Abstract Thermal management is critical in ensuring that safety, functionality, and battery life in lithium-ion batteries are not compromised, especially when undergoing high-discharge currents. In traditional battery thermal management systems (BTMS), there are limitations in effectively suppressing a relatively high rate of temperature increases when in operation. To address this problem in traditional BTMS, this study investigates how changes in metal fin thicknesses affect heat transfer and temperature regulation in a BTMS that has a phase change material (PCM) to suppress overheating. The analysis considered two different types of PCMs with different thermal properties and thicknesses of 3 mm and 5 mm. The thicknesses of metal fins for both discharges of 5C and 8C were optimized. The generation of actual heats in batteries undergoing operation has been assumed to have a temperature dependency expressed as the lumped-capacity resistance. With a 5C discharge rate, the temperatures of batteries in the system with the first PCM were lower than those in the system with the second PCM. However, in a scenario involving a rate of 8C, temperatures were better controlled with a lower thickness of layers in the second PCM. On the other hand, for a thicker setup, temperatures were better controlled in a system with the first PCM. Moreover, temperatures for a safe operation were obtained only for a setup consisting of a 5 mm layer of PCM and 8 mm fins in a system with a 8C discharge rate. The current study explains how a battery can benefit thermally when a specific fin and PCM are used. Results obtained illustrate that batteries can benefit thermally when a suitable fin and PCM are selected. The study can provide important information required for designing advanced battery thermal management systems to improve safety and efficiency in batteries that power electrical vehicles.

Abstract This study investigates the linear stability of mixed convection
flow of an Oldroyd-B viscoelastic fluid in a vertical porous channel
subjected to differential heating. To understand how thermal properties
influence stability, two representative Prandtl numbers, Pr = 0.7
and Pr = 7 are considered. The governing equations for basic flow and
generalised eigenvalue problem, based on the viscoelastic form of the
volume averaged Navier-Stokes equations, are solved using a spectral
collocation approach. The analysis shows that variations in Reynolds
number strongly impact the critical Grashof number (Gr′), the propagation
speed of disturbances, and the overall instability mechanisms.
The results further highlight that flow stability is governed by a delicate
balance between fluid elasticity, buoyancy-driven forces, and the
permeability of the porous medium. The fluids with lower Prandtl
number display a stronger sensitivity to elasticity effects and further,
the fluid elasticity has significant impact on the disturbance convection
patterns inside the channel. The nature of instability is commonly
found to be thermal-bouyant for the range of parameters considered
in this study.

Near-infrared (NIR) blocking ophthalmic lenses are commercially available, but data supporting their properties and performance are difficult to find. This study aims to provide objective data through clinical results of NIR blocking ophthalmic lenses and to verify color reproducibility and thermal properties and performance according to the influence of NIR for practical use. Near-infrared blocking spectacle lenses (NIBSL) (polymerized, coated) and other types of spectacle lenses (clear, tinted) were manufactured and classified into 0, 2, and 3 grades (10 types) of luminous transmittance. The near-infrared environment was configured and the color reproducibility evaluation factors, such as sharpness (MTF50), chromatic aberration (CA), and color accuracy (△E), were compared in an outdoor environment (1000 lux). The thermal properties were analyzed by observing the temperature changes on the surface of the spectacle lens and pig skin in real time in environments of 36℃ and 60℃. NIBSL showed no difference in object discrimination and color recognition compared to other types of spectacle lenses. In terms of thermal characteristics, NIBSL showed a smaller increase in lens surface temperature, and the pig skin temperature was maintained lower, showing excellent insulation performance. These results suggest that NIBSL can be used in everyday life without problems in visual ability and color reproducibility, and may be useful in protecting eyes from the thermal hazards of near-infrared light. In addition, we presented a new research method that improves the accuracy and reliability of optical functional spectacle lenses in the near-infrared region (harmful to humans).

The development of enhanced performance of biobased composite films with hydrophobic, chemical resistance, thermal and electrical properties.

Green synthesis of PVC/ZnO nanoparticles: microstructure, thermal properties, optical behavior, radiation shielding efficiency, and mechanical performance

Tunable field-dependent electronic and thermal conductivity of tetragonal germanene nanoribbons under temperature, chemical potential and external fields.

Nano-channel anisotropic optical material containing ∼5 nm diameter aligned Se nanowires with enhanced photo-structural effects and unique photonic, electronic, phononic and thermal properties

Influence of fused deposition modeling parameters on the mechanical and thermal properties of 3D-printed PEEK dental endosseous implants.

Comprehensive study of naphthyl cored thiophene based stilbene derivatives: synthesis, photophysical behavior, crystallography and thermal properties

On chitosan-agarose-gelatin hydrogels functionalized with tannic acid and metallic ions for regenerative medicine.

Ammonia is an important component in the manufacture of fertilizers and various chemicals, and its production mainly relies on the energy-intensive Haber-Bosch process. To overcome this, there has been growing interest in using photocatalysis as an alternative approach for ammonia synthesis under ambient conditions. Plasmonic nanomaterials have been considered to be particularly promising due to their localized surface plasmon resonance (LSPR) effects that combine the advantages of photochemical and thermal properties in one system. This review introduces the fundamental principles of LSPR effects, including hot carrier injection, photoheating and near-field enhancement. It then undertakes a comprehensive analysis of the current state-of-the-art catalysts for plasmon-driven photocatalytic ammonia synthesis. Finally, it proposes a brief outlook on the strategies for the design of plasmonic photocatalysts, advances in in situ characterization and theoretical simulations, standardization of the reaction conditions and detection technologies for ammonia production.

Tailoring polyamide 66 nanocomposites with plasma-engineered carbon nanotubes for advanced mechanical and thermal properties

Recent breakthroughs in the field of high-entropy alloy nanoparticles (HEA NPs) have significantly expanded their potential applications (such as catalysis or energy storage) making them promising candidates for use over a wide temperature range. However, their thermal stabilities are not yet fully understood, which is crucial to their future development. To better understand these phenomena and the underlying mechanisms, we performed molecular dynamics simulations by adopting an incremental approach to investigate the structural and thermal stability of CoNiPtCuAu HEA NPs, as well as their ternary and quaternary sub-alloys. More precisely, CoNiPt ternary system is first considered and then Cu and Au atoms are progressively introduced with the aim to analyse and quantify the thermal stability of HEA NPs in terms of their melting temperature and segregation mechanisms. Through our atomic-scale simulations, we demonstrate the negative impact of Au and Cu atoms on thermal stabilisation, whose presence at the surface tends to favour melting of the NPs because of their low melting point. These detailed analyses provide a robust and relevant research approach for identifying the key parameters influencing the thermal stability of HEA NPs, which is essential for obtaining such nano-objects with optimised structural and thermal properties.

Molecularly imprinted polymer-based HPLC column and smart syringe for selective extraction of quercetin from complex plant extracts: A sustainable and green approach.

We constructed two-dimensional (2D) molecular frameworks composed of lithium ions (Li+) and dinitrile aliphatic ligands to explore their mechanical and thermal properties. Calorimetry, X-ray diffraction, density functional theory calculations, alternating current impedance, and solid-state nuclear magnetic resonance evidenced behaviours and properties originating from the weakly linked 2D system. We found low melting temperatures (<100 °C), high mechanical deformability, large positive and negative thermal expansion, and metal ion diffusion. These features were uniquely observed in the integration of Li+ and dinitriles into extended molecular structures.

Novel mono glyceryl ethers (MGEs) were synthesized from biomass-based sources and used as diol monomers for synthesizing comb-shaped polyesters.

Influence of intermolecular interaction about polyhedral oligomeric silsesquioxane and silicone rubber on mechanical and thermal properties