Universidad Arturo Prat is a university in Chile. It is a derivative university part of the Chilean Traditional Universities.The university was created in 1981 from the former campus of the University of Chile in Iquique.
Recent research has emphasized the potential of combining different electrode materials to enhance the performance of asymmetric supercapacitors for energy storage applications. In this study, an asymmetric supercapacitor was developed using cobalt sulfide (CoS)-embedded activated carbon (AC), denoted as CoS@AC, as the positive electrode, while AC alone served as the negative electrode. Initially, micro-flower morphology of CoS was synthesized via a hydrothermal method, and layered morphology of AC was prepared through the carbonization of Acorus calamus. Then CoS@AC nanocomposite was fabricated using a wet impregnation method and its structural, morphological analysis was carried out. The morphological analysis of CoS@AC nanocomposites confirmed the presence of both micro-flower morphology of CoS and layered morphology of AC structures. The TEM analysis of CoS@AC nanocomposite revealed the presence of both micro-flower-like (CoS) and layered-like structure (AC), and the HRTEM analysis showed an interplanar spacing of 0.236 nm related to CoS (101) XRD diffraction. The BET analysis of CoS@AC nanocomposites shows a nearly type-I isotherm with a surface area of about 1145 m2/g, an average pore size of about 4.23 nm, and a pore volume of 0.451 cc/g. Finally, the CoS@AC‖AC electrode demonstrated enhanced electrochemical performance, achieving a specific capacitance of approximately 234 F/g, an energy density of 83.2 Wh/kg, and a power density of 16,089 W/kg. Further, the stability analysis was carried out for 2000 cycles, which showed better stability performance. These results strongly recommend that the CoS@AC‖AC system is favorable for asymmetric supercapacitor applications.
Multi-walled carbon nanotubes (MWCNTs) enable efficient photothermal coatings for thermal management applications due to their broadband near-infrared absorption and high thermal conductivity. This study optimizes MWCNT-polymer formulations using random forest machine learning (ML) to maximize photothermal conversion efficiency (η), targeting inputs like MWCNT concentration (1–10 mass% ), polymer type (polystyrene, polyethylene, and polyurethane), and coating thickness (100–500 nm) prepared via dip, spray, or spin coating on glass substrates. A dataset of 500 + experimental points (features: composition, processing parameters; target: η and steady-state temperature rise) underwent preprocessing (normalization and categorical encoding) and fivefold cross-validation. The random forest model achieved R2 = 0.93 (validation), outperforming baselines by predicting optimal formulations (e.g., 5 mass% MWCNT in polyurethane yielding η = 85
Abstact. Desert spiders generally are tolerant or resistant to desiccation, as they must develop strategies to live in high temperatures and prevent continued water loss. However, in extreme conditions, as the temperature increases, their metabolism increases, so they could lose water as the temperature rises. The objective of this work was to determine the effect of temperature on water loss in the spider Sicarius thomisoides. Spiders were subjected to different temperatures: 20 degrees C, 30 degrees C and 40 degrees C. Our results indicate that this spider has excellent resistance to desiccation, since, on average of the three temperatures, losing only 7.25 +/- 3.14% of the initial weight at 40 degrees C, being able to resist extremely high temperatures. In addition, we could not determine a significant effect of body size. Water loss was similar among individuals of different stage of development.
Determining nickel extraction during the roasting-reduction stage of the Caron process is an essential tool for controlling the metallurgical efficiency of the technology. This study evaluated the performance of a new semi-empirical kinetic model for predicting nickel extraction during the reduction of lateritic ores predominantly composed of iron oxides and oxyhydroxides in multiple-hearth furnaces. To achieve this, the lateritic ore was characterised by scanning electron microscopy (SEM) before and after the reduction process. The temperature in hearth six was varied between 495 and 780 degrees C by adjusting the post-combustion air supply. The proposed model demonstrated high predictive accuracy for nickel extraction, with absolute and residual errors below 1.70% and 1.15%, respectively. The findings emphasise the importance of controlling metallurgical efficiency through mathematical models that incorporate key technological variables and the kinetic behaviour of the process.
We determine the universal part of pseudoentropy for small shape deformations of spherical entangling surfaces in the context of de Sitter/conformal field theory (dS/CFT) correspondence. The leading correction at quadratic order in the deformation parameter is controlled by the analytic continuation of the coefficient of the two-point stress-energy tensor correlator in AdS/CFT (i.e., L star jAdS -> -i L star jdS), thereby establishing the sphere as a local extremum. The same structure holds in higher-curvature theories, as we check explicitly for quadratic curvature gravity, suggesting a universal behavior across nonunitary holographic CFTs. Our findings extend the Mezei formula to the dS/CFT setting and indicate that the shape dependence of pseudoentropy in dS holography resembles that of entanglement entropy in AdS space. Thus, we conjecture this coefficient to be the CT for the nonunitary CFT dual.
