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En la actualidad, uno de los mayores retos educativos sigue siendo superar las dificultades que genera el aprendizaje matemático en el alumnado de Educación Primaria y Educación Secundaria. Recientemente, se ha incrementado la investigación sobre el aprendizaje y la cognición matemática debido a las consecuencias personales y sociales del fracaso enel aprendizaje. Una de las líneas de trabajo enfatiza la conveniencia de realizar intervenciones que incorporen los procesos cognitivos implicados en el aprendizaje de las matemáticas, y hagan uso de estrategias innovadoras como el método de cálculo Abierto Basado en Números (ABN). El presente estudio pretende analizar el impacto del programa formativo online para la implantación del método ABN en cursos altos de Educación Primaria y primer ciclo de Educación Secundaria Obligatoria. El proyecto se distribuye en cuatro fases: (1) Selección de escuelas; (2) Programa formativo online para docentes; (3) Estudio empírico para analizar la efectividad del método ABN; y (4) Transferencia de resultados y diseño de materiales y APP educativas matemáticas. Se presentan los resultados obtenidos en la primera etapa, con el objetivo de analizar el impacto del programa formativo y la incorporación de materiales manipulativos para diversos contenidos matemáticos. Los participantes del programa formativo pertenecen a centros educativos de la provincia de Cádiz y fueron seleccionados incidentalmente. La muestra está compuesta por 40 participantes (19 investigadores, 3 docentes expertos en ABN, 18 docentes y 3 estudiantes de máster en Educación Secundaria). Se presentan los resultados extraídos tras la formación del profesorado y las prácticas de aula llevadas a cabo, los cuales muestran la necesidad de formación del profesorado para la incorporación de dinámicas alternativas en los cursos altos de Educación Primaria. Se espera abrir nuevas líneas de investigación basadas en la implementación de programas y talleres para la aplicación de estrategias innovadoras en los centros educativos.

The integration of polymer, metal, and ceramic materials in hybrid structures represents a potential but underexplored alternative for biomedical applications. Here, we present a methodology for manufacturing a mechanically strong and durable hybrid overlap structure from a composite of green high‐density polyethylene (HDPE) and hydroxyapatite (HA) compatibilized with HDPE‐g‐MAH joined to a substrate of Ti6Al4V alloy. This process involves laser structuring of micro‐scale grooves on the metal surface, followed by injection overmolding of the polymer composite. A hybrid overlap joint with strong interfacial anchoring was achieved, resulting in outstanding joining strength and fatigue life. This achievement holds significant promise for future biomedical applications. Highlights: Joining of composite of HDPE–HA with Ti6Al4V alloy via injection overmoldingLaser texturing was effective in improving mechanical interlockingA hybrid joint with high shear strength and fatigue life was developedThe hybrid joint is promising for biomedical applications [ABSTRACT FROM AUTHOR]

Lightweight polyamide composites and structures have been widely studied and employed in several industrial sectors. In this study, the development of a nanocomposite of polyamide 6 and graphene oxide (PA6‐GO) by melt‐compounding and the joining with aluminum alloy AA6061 through direct‐adhesion injection overmolding are addressed. PA6‐GO nanocomposite exhibited well‐dispersed thin (300 nm) GO platelets distributed within the PA6 matrix, which resulted in an increase of 21% in the tensile modulus and 16% in the yield stress for a filler loading of 0.5 wt%. PA6‐GO/AA6061 hybrid joints showed good mechanical anchorage through the complete filling of the polymer into micro‐scale grooves designed onto the metal surface, which ensured outstanding shear strength of 7.1 ± 1.0 MPa, comparable to other polyamide‐metal hybrid joints reported in the literature. This indicates that the processing routes and materials developed are promising for lightweight engineering applications. Highlights: A PA6‐GO nanocomposite with enhanced tensile properties was developed.A joint of PA6‐GO and AA6061 with outstanding shear strength was obtained.Fast and efficient melt‐processing routes were employed.These materials are promising for lightweight engineering applications. [ABSTRACT FROM AUTHOR]

We investigate the 9Be+208Pb elastic scattering, breakup and fusion at energies around the Coulomb barrier. The three processes are described simultaneously, with identical conditions of calculations. The 9Be nucleus is defined in an α + α + n three-body model, using the hyperspherical coordinate method. We first analyze spectroscopic properties of 9Be, and show that the model provides a fairly good description of the low-lying states. The scattering with 208Pb is then studied with the Continuum Discretized Coupled Channel (CDCC) method, where the α + α + n continuum is approximated by a discrete number of pseudostates. Optical potentials for the α+208Pb and n+208Pb systems are taken from the literature. We present elasticscattering and fusion cross sections at different energies.

We report on a recent work on the low-energy behavior of the breakup cross section in so far as it has important role in the fusion of weakly bound and halo nuclei at near-barrier energies. We assess the way the nuclear component of this cross section scales with the target mass. In complete accord with previous finding at higher energies we verify that the low energy behavior of the breakup cross section for a given projectile and relative center of mass energy with respect to the Coulomb barrier height scales as the cubic root of the mass number of the target. Surprisingly we find that the Coulomb component of the breakup cross section at these low energies also obeys scaling, but with a linear dependence on the target charge. Our findings are important when planning for experiments involving these exotic nuclei.

Motivated by the strong synergy between structure and nuclear reactions we have performed a phenomenological analysis using available elastic scattering data for collisions of tightly-bound ( 10 Be , 10 B , 10 C , 11 B , 12 C , 16 O ), weakly-bound ( 6 Li , 7 Li , 8 Li , 9 Be ), and exotic ( 6 He , 8 B and 11 Be ) nuclei on 58 Ni and 64 Zn targets at energies close to the Coulomb barrier. After a proper reduction, the cluster configuration and dynamics effects in the total reaction cross section are discussed. Also, an approach based on the interaction distances is used to investigate static and dynamic effects in the elastic scattering of light nuclei. A correlation between the critical interaction distance and binding energy for a given configuration is observed. [ABSTRACT FROM AUTHOR]

We propose the use of neutron poisons in reactions induced by radioactive beams as a test of theoretical models aiming to relate neutron capture in nuclei with neutron surrogate reactions such as (d , p) reactions. We exploit the approximations necessary to obtain a direct relation between the two reactions: surrogate versus neutron capture. We also show how this is intimately related to the momentum distribution of the neutron within the deuteron. The models we use are based on the theory of inclusive breakup reactions commonly employed in the treatment of incomplete fusion and surrogate method. Such theories were developed in the 1980s by Ichimura, Austern and Vincent [Phys. Rev. C32 (1985) 431], Udagawa and Tamura [Phys. Rev. C24 (1981) 1348] and Hussein and McVoy [Nucl. Phys. A445 (1985) 124]. We use these theories to derive an expression for the proton yield in the reaction A (d , p) X. The capture reaction n + A → X is then extracted using reasonable approximations. By recalling an old method proposed by Serber [Phys. Rev.80 (1950) 1098; Proc. Roy. Soc. A208 (1951) 559] we explain how the momentum distribution of neutrons within the deuteron will depend on the short-range dependence of the nucleon–nucleon force. The relevance of our work to nucleosynthesis in the rapid neutron capture process is emphasized. [ABSTRACT FROM AUTHOR]

We investigate three of the most frequently used methods to reduce fusion and total reaction excitation functions. For this purpose, we apply them in two situations. First, we consider theoretical cross sections obtained by single-channel calculations based on standard optical potentials. In this case, the cross sections are not influenced by any particular nuclear property. Thus, the method is successful if the cross sections for different systems are about the same. In the case of fusion excitation functions, we found that the fusion function method works very well, being much better than the other two methods. Regarding total reaction excitation functions, none of the methods is satisfactory. Their reduced reaction cross sections maintain a strong dependence on the atomic and mass numbers of the collision partners. However, they perform reasonably well when compared to similar systems. Next, we use the three methods to reduce experimental fusion and reaction cross sections for many systems, over a broad mass range. Our conclusions are consistent with the ones reached for our theoretical cross sections, resulting from single-channel calculations. That is, the fusion function method is the best for fusion data, whereas none of the three methods works for total reaction. [ABSTRACT FROM AUTHOR]