In this work, the effects of seawater exposure and specimen geometry on the mechanical performance of 3D-printed Acrylonitrile Butadiene Styrene (ABS) and carbon fiber-reinforced ABS (ABS/CF) were investigated. Enclosed 3D printers were used to avoid shrinkage and warping of ABS and ABS/CF. The standard specimen types in this research work were ASTM D638 type IV, ISO 527-2 type 1BA, and ASTM D3039 full-section specimens. The tensile tests were strain-controlled tests with a strain rate of 0.1 min− 1. Firstly, the effects of the different specimen types on the tensile strength and Young’s modulus of unaged (as-printed) ABS and ABS/CF were analyzed. Secondly, the three types of specimens were immersed in seawater for 1, 2, and 3 weeks to evaluate moisture absorption and the degradation of the mechanical properties. The results indicated that the test specimen type had a statistically significant effect on the mechanical properties of ABS and ABS/CF, with the ISO 527 specimen exhibiting the lowest tensile strength and Young’s modulus. Moreover, all ABS and ABS/CF specimens showed moisture uptake of less than 1
The modern world is shifting towards digitalization and miniaturization, leading to higher flux densities in electronic components and machines. However, conventional cooling methods, such as air-cooled smooth channels, are proving inadequate for removing the huge amounts of heat generated, thereby compromising the reliability and operational lifespan of electronic systems. This necessitates urgently exploring and analyzing modern techniques like microchannel cooling to improve its efficiency. This work uses ANSYS to conduct numerical simulations and investigates the heat transfer and flow behavior in a microchannel heat sink. The smooth channel is used to investigate and validate the flow behavior with the available literature. Moreover, a biomimetic design using trefoil cavity was mounted on different walls of smooth channels to see the performance improvement. The performance comparison of a smooth channel with a cavity channel was made by utilizing the heat transfer coefficient, Nusselt number, friction factor, pressure drop, thermal enhancement factor, thermal resistance, and thermal transport efficiency. The study reveals that adding trefoil cavities has improved the performance of the microchannel heat sink. Furthermore, it was observed that the addition of trefoil cavities to the base wall (MC-BWTC) has superior performance than that of side wall (MC-SWTC) and all wall trefoil cavities (MC-AWTC). Specifically, MC-BWTC increases the overall performance of smooth channel by 31 %, MC-SWTC by 21 %, and MC-AWTC by 17 %, respectively.
In this study, a series of ceria-doped cobalt-based composites were synthesized via the incorporation of cobalt and cerium precursors into trimesic acid-based metal-organic frameworks (MOFs), followed by pyrolysis to obtain Co-CeO2/C hybrid materials. The thermal decomposition of the MOF structure facilitated the in-situ formation of a conductive carbon matrix comprising carbon nanotubes (CNTs) and carbon nanospheres, catalyzed by cobalt nanoparticles. Among the prepared composites, the 5Co-5Ce/C sample exhibited the most promising electrochemical performance, delivering a high specific capacitance of 839F g- 1 at a current density of 0.1 A g- 1 and demonstrating excellent cycling stability, with 97% capacitance retention after 6000 chargedischarge cycles at 10 A g- 1. The superior performance is attributed to the synergistic effect between cobalt and cerium oxide, wherein CeO2 not only enhances faradic charge storage through reversible redox reactions but also promotes the development of a mesoporous structure. Cerium was found to influence the crystallization behavior of cobalt during pyrolysis, thereby regulating the growth and distribution of CNTs and nanospheres. This structural refinement contributes to an increased electrochemically active surface area and improved ion transport kinetics, leading to enhanced overall capacitive behavior. These results highlight the potential of Co-CeO2/C composites as promising electrode materials for high-performance supercapacitor applications.
A new copper(II) complex namely [Cu(dphen)(Hpht)Cl] (1) (dphen = 2,9-dimethyl-1,10-phenanthroline and Hpht1-= monoanion of o-phthalic acid), was synthesized and characterized using UV-visible, Fourier transform infrared spectroscopy (FTIR) and single-crystal X-ray diffraction (SCXRD) techniques. Single crystal X-ray diffraction analysis discloses that the Cu(II) ion exists in a distorted square pyramidal geometry, as it is coordinated to two oxygen atoms of the carboxylate moiety of 1,2-benzenedicarboxylate monoanion, two nitrogen atoms of the chelating dphen ligand and one chlorine atom. Complex 1 showed significant antimicrobial activity against E.coli and Staphylococcus aureus. Its DNA binding potential was evaluated via agarose gel electrophoresis using genomic DNA. Density functional theory (DFT) has been employed to obtain the influential parameters at B3LYP functional. Geometry optimization, energy and energy gap, FMO analysis and thermodynamic indices evaluation emphasized the structure activity relationship and biological implication. SwissTargetPrediction, online webserver, highlighted strong affinity toward target classes GPCRs (53.3%) and enzymes (20%) mainly, correlating with the observed biological activity of the complex 1. Furthermore, extensive molecular docking studies were carried out to understand the potential binding interactions of complex 1 with DNA double helix and the target BSA protein.
This study investigates double diffusive convection in viscous fluid flow over a vertically aligned, heated, porous, and non-uniform cylinder exhibiting nonlinear stretching and shrinking. The field variables velocity, temperature, and concentration are modeled using nonlinear algebraic functions. By applying similarity transformations, the governing partial differential equations are reduced to a system of four coupled nonlinear ordinary differential equations, solved using MATLAB’s bvp4c scheme. The results show that increasing the thermal and solutal Grashof numbers by a factor of 2 leads to an increase of approximately 58% in the axial velocity near the cylinder surface, enhancing assisting flow behavior. An increase in the nonlinear stretching parameter reduces the thermal boundary layer thickness by up to 35%, while the mass transfer rate increases by over 40% in highly porous conditions. Skin friction coefficients and Nusselt and Sherwood numbers display strong nonlinear sensitivity to surface roughness and porosity. Notably, overshoot in velocity profiles is observed under specific parameter conditions, whereas temperature and concentration profiles remain monotonic. This model generalizes previous studies by encompassing both uniform and non-uniform surface properties and provides a versatile tool for simulating practical heat and mass transfer processes.
